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Pest control is an essential aspect of rice cultivation. The golden snail (Pomacea speciosa) is one of the pests in rice fields. Damage to rice plants due to golden snail attacks has occurred in several provinces in Indonesia and several countries such as the Philippines, Thailand, Japan, and Malaysia. Various steps to control golden snails have been carried out, both mechanically, biologically, and chemically. However, each biological and mechanical control of golden snails is impractical to apply to very large rice fields. Meanwhile, the control of golden snails using synthetic molluscicides such as Brestan and Dimotrin is minimal because it can pollute the environment and cause the death of fish and the rice plant itself. To suppress the emergence of environmental pollution problems in overcoming this golden snail, natural molluscicides from plant materials are studied. Several plant species have been known to have anti-mollusk properties, one of which potentially is the Jayanti plant {Sesbania sesban (L.) Merr.}. This study aimed to evaluate the anti-mollusk performance of S. sesban for controlling golden snails, a pest of rice plants. The dry powder of S. sesban leaves was extracted in stages with a series of solvents of petroleum ether, chloroform, and ethanol to obtain an extract fraction that was selected as a mollucicide. Each extract fraction produced was tested for its toxicity to the gold snail, carp, rice germination, and rice plant growth. Data on the mortality of golden snail and carp fish, the percentage of germination inhibition, and rice growth were processed by probit analysis, respectively. The outputs of the analysis were LC50 of each extract fraction for golden snails and carp. The ratio of LC50 for golden snail with LC50 for carp indicated each extract fraction's physiological selectivity of anti-mollusk properties. The results showed that the highest lethal toxicity to gold snails was indicated by the extract fraction-ethanol, while to carp, it was indicated by the extract fraction-chloroform. Each extract fraction of S. sesban leaves did not inhibit the germination and growth of rice plants. The extract fraction- ethanol had the highest anti-mollusk selectivity compared to the other two fractions. Bioactive examination showed triterpene saponins from the extract of S. sesban leaves, with the highest relative levels in the ethanol fraction compared to the other two extract fractions.

Phytochemical compounds are secondary metabolites of plants useful as antimicrobial agents. Botanicals are being explored for bioactive compounds with antimicrobial properties against phytopathogens. Little information is available on the phytochemical and antimicrobial activity of Calliandra calothyrsus, Leucaena diversifolia and Sesbania sesban against Cercospora zeae-maydis and Xanthomonas campestris pv. musacearum. The aim of the study was to determine the phytochemical and antimicrobial properties of leaf extracts of C. calothyrsus, L. diversifolia and S. sesban against C. zeae-maydis and Xc. pv. musacearum. Dried leaves were extracted in methanol and aqueous solvents and screened for phytochemical and antimicrobial activity using Kirby-Bauer’s disk diffusion and poisoned food technique methods. Sesbania sesban extracts contained all the phytochemical tested; tannins, terpenoids, steroids, saponins, flavonoids, and alkaloids, Leucaena diversifolia lacked alkaloids while Calliandra calothyrsus lacked steroids and alkaloids. The extracts were active against Cercospora zeae-maydis and Xc.pv. musacearum with Sesbania sesban having greater radial inhibition activity. There was no significant difference in the antimicrobial activity between the lowest concentrations (25% and 25mg/ml) and highest concentrations (75% and 75mg/ml) in all the three plant extracts. Growth inhibition observed could be as a result of the different chemical compound observed in the extracts. Presence of alkaloids in Sesbania sesban could explain the greater growth inhibition of the pathogens under study. The results form the basis for further research that could lead to isolation and development of antimicrobial agents. Therefore, these plants can be used as an alternative to synthetic chemicals to control Cercospora zeae-maydis and Xanthomonas campestris pv. Musacearum.

We investigated the effects of gibberellic acid (GA3) and kinetin on seed germination of S. sesban L. and S. rostrata L. The matured seeds used for this study were obtained from International Institute for Tropical Agriculture (IITA) Ibadan, Nigeria. The seeds were harvested in 2014 and stored dry in a glass container and kept (15°C) in the refrigerator. The viability of the seeds were determined by floating the intact seeds in water and water uptake (imbibition) was carried out. Four replicates of 20 seeds per replicate were germinated and the seeds observed daily and final count was recorded after 14 days of incubation at 30°C. Intact seeds were soaked in gibberellic acid (GA3) and kinetin for 24h and germination percentage taken. The results from the water absorption demonstrated that the seeds of S. rostrata is more permeable compared to S. sesnban as indicated by higher water absorption of seeds of S. rostrata (70%) to S. sesban (25.4%) after 24hrs of incubation. The anatomy of the seed coats indicated the presence of water and gas impermeable tissues namely cuticle, macrosclereids, osteosclereids and disintegrated parenchyma layer. Generally, 0.1 mM kinetin and GA3 enhanced significant germinations compared to the control with 0% germination for the 14 days period of germination. The percentage germination of seeds of S. sesban and S. rotrata subjected to different treatments and germinated in 0.1 mM GA3 and water showed a progressive decrease in germination. From our study, 0.1 mM GA3 and Kinetin significantly enhanced seed germination of S. sesban and S. rostrata.

Direct seeding is considered as an option for afforestation programs to rehabilitate degraded lands. However, scant knowledge is available on the effect of seed sowing techniques on the germination of different woody plants in a semi-arid degraded area. Therefore, the objectives of this study paper are 1) to evaluate the effects of broadcasting vs seed bury on the germination of 15 different woody plant species in a degraded semi-arid area 2) to select woody plants that can result in higher germination percent in the field for restoration projects. To achieve the objectives, a study was carried out in the field, with a randomized complete block design (RCBD). One-way ANOVA, t-test and descriptive statistics were used to analyze the data. The result indicated that the average germination percent for buried and broadcasted seeds were 18.1% and 5.2%, respectively. Among the broadcasted species seeds, Schinus molle achieved the highest germination (23.3%) while Terminalia browni achieved the lowest germination (0.25%). Among the different species seeds that were buried, Dolanix regia achieved the lowest germination (1.5%) while Sesbania sesban resulted in the highest germination (64%). The t-test result revealed a significant difference in the mean germination of the broadcasted and buried seeds (p

This study evaluated the impact of conventional practices (fertilizer alone) and diverse farming approaches (such as green manuring, farmyard manure application, rice-residue incorporation, residue mulching, residue removal and residue burning) on soil attributes. A total of thirty-five farm sites were selected, with five sites (replications) for each farming approach system, which were used over the past three years in the study farms. Characterization of rice residues of all cultivars, green manure crop (sesbenia: Sesbania sesban) and decomposed farmyard manure samples showed differential behaviours for macronutrients and micronutrients. Continuous application of inorganic fertilizers significantly influenced soil attributes, especially electrical conductivity, nutrient contents, bacterial and fungal population and soil enzymatic attributes. The crop residue treatments favourably influenced the soil parameters over the control. Crop residue incorporation or burning significantly increased soil available potassium, microbial biomass, enzymatic activities and organic carbon when compared with applications of chemical fertilizer alone, while total nitrogen content was increased by residue incorporation. However, green manuring and farmyard manure applications showed inferior responses compared with residue management treatment. It is therefore recommended that bioresources should be managed properly to warrant improvements in soil properties, nutrient recycling and the sustainability for crop productivity, in order to achieve sustainable development goals for climate action.

An agroforestry land use system aimed at improving the productivity of smallholder dairy farms using Calliandra calothyrsus and Sesbania sesban shrubs as feed supplements was introduced to semi-commercial SDFs in Meru, Kenya, as part of a field trial. The objective of this study was to assess the impact of using the C. calothyrsus and S. sesban on family income and livelihoods during the 16-month trial period. Eighty farmers randomly allocated to four groups (nutrition, reproduction, combined nutrition and reproduction, and a comparison group) were enrolled in this study. The nutrition intervention included nutritional management advice and provision of 150 C. calothyrsus seedlings and 150 S. sesban seedlings to each farm. Farms were visited every 1-2 months during the trial to collect data on milk production and feeding practices during the previous day. Seventy of these farms completed the trial and were interviewed post-intervention. Partial budget analysis of their farms was done by comparing changes in average monthly profits (from milk) and feeding costs/cow for the first 6 months and last 6 months of the intervention. Focus group discussions were used to collect qualitative information on livelihood effects from the trial. There was a KES 2,380.3 (USD 23.5) increase in average monthly profit/cow in the nutrition group comparing the first and last 6 months of the trial, representing a 68.8% improvement (p = 0.02). Average feeding costs significantly decreased across all groups over the trial period. Knowledge on dairy cow nutrition, level of confidence on calf management, and feeling of empowerment to raise calves/heifers to achieve first calving by 27 months were higher among farmers in the nutrition and combined groups than farmers in the other groups. There were positive direct and indirect impacts on the income and livelihoods of farmers in the two groups receiving nutritional interventions. Agroforestry, using C. calothyrsus and S. sesban shrubs can improve household livelihoods if adopted by SDFs in Kenya. Key words: Smallholder dairy, agroforestry, partial budget analysis, leguminous shrubs.

There is a growing interest in protein supplementation of dairy-cow diets using leguminous shrubs. The study objective was to ascertain the association between diet supplementation with Calliandra calothyrsus and Sesbania sesban and milk production in dairy cattle on commercial smallholder farms. This trial involved 235 cows from 80 smallholder dairy farms in Kenya randomly allocated to 4 intervention groups: (1) receiving Calliandra and Sesbania and nutritional advice; (2) receiving reproductive medicines and advice; (3) receiving both group 1 and 2 interventions; and (4) receiving neither intervention. Farm nutritional practices and management data were collected in a questionnaire, and subsequent physical examinations, mastitis tests, and milk production of cows on the farm were monitored approximately monthly for 16 months. Descriptive and univariable statistical analyses were conducted, and multivariable mixed-model regression was used for identification of factors associated (P<0.05) with daily milk production. The mean milk production was 6.39 liters/cow/day (SD = 3.5). Feeding Calliandra/Sesbania to cows was associated (P<0.0005) with an increase in milk produced by at least 1 liter/cow/day with each kg fed. Other variables positively associated with ln daily milk production in the final model included feeding of Napier grass, amount of silage and dairy meal fed, body condition score, and appetite of the cow. Other variables negatively associated with ln daily milk production in the final model included amount of maize germ fed, days in milk, sudden feed changes, pregnancy, and subclinical mastitis. In conclusion, our field trial data suggest that use of Calliandra/Sesbania through agroforestry can improve milk production in commercial smallholder dairy farms in Kenya. Agroforestry land use systems can be adopted as a way for dairy farmers to cope with feed shortages and low crude protein in farm-available feeds for their cows.

This study was designed to provide strain for studying the ecology of Rhizobium when it was used to inoculate seed sown in the soil or in the field. Naturally occurring antibiotic resistant mutant strains of Rhizobium PMA295 nodulating Sesbania sesban were selected by antibiotic selection method. The isolates should be as effective in nitrogen fixation as the parental wild-type strain. Authentication of mutant isolates showed that these rifampicin mutant isolates could nodulate test plant and most nodules formed by the rifampicin 50 ppm and streptomycin 500 ppm mutant isolates were red in colour. These twenty isolates can be regarded as rhizobia. The most effective mutant, isolates PMA295 selected on rifampicin 50 ppm was also resistant to rifampicin 60, 70, 80, and 90 ppm. The effectiveness of most mutant strains was not significantly different from their parent strains. The rifampicin 50 ppm mutant strain of Rhizobium PMA295 could be used as inoculant for ecological study.

Sesbania sesban (L.) Merr., (family Fabaceae) commonly called as "dhaincha" in India, is a multi-purpose crop used as a cover crop, as green manure, in the paper industry as well as animal fodder. The leaves of Sesbania contain high amounts of pinitol, which acts as an anti-diabetic agent (Misra and Siddiqi 2004). During July/August from 2017 to 2019, Sesbania plants exhibiting typical Rhizoctonia-like symptoms, including collar rot, wilting, and necrotic lesions on stems were regularly observed at ICAR-Central Potato Research Institute Regional Station, Meerut, Uttar Pradesh. The disease incidence ranged between 5 and 10% in a Sesbania crop being grown on 25 ha in Sesbania-potato rotation. Ten diseased plants were collected from different fields and brought to the laboratory for diagnosis. Affected stem pieces approximately 5 mm in size were surface sterilized with 2% sodium hypochlorite, washed twice in sterilized water and air dried. Four diseased pieces per plate were inoculated on 2% water agar amended with 2% streptomycin sulfate and incubated at 28±1℃ in the dark. All four affected pieces began to produce Rhizoctonia-like colonies after 48 h of incubation and in total eight isolates were purified and stored at 4℃ for further use. The colonies of eight isolates were evaluated and all were whitish during early growth and became light brown after 72 h. Dark-brown sclerotia appeared in the random pattern on PDA after 120 h. Microscopic observations showed that all isolates had hyphal branching at right angles with slight constriction at the base of the branch, presence of dolipore septum near the branching and multinucleate individual hyphae compartments (Sneh 1991). Based on these morphological characteristics, the fungus was identified as Rhizoctonia solani. All isolates were further characterized to determine anastomosis group (AG) by pairing with a known AG tester of R. solani AG-1-IA (ITCC 7650), AG-1-IB (ITCC 5650), and AG-3 (RS-20) procured from Indian Type Culture Collection, Division of Plant Pathology, ICAR-Indian Agricultural Research Institute, New Delhi and ICAR-Central Potato Research Institute, Shimla, Himachal Pradesh, India, respectively. All eight isolates showed positive anastomosis with a known AG-1-IA tester isolate while no anastomosis was observed with other known tester isolates (Carling 1996). Furthermore, a single ~265 bp amplicon was amplified with AG-specific primer, which was specific to R. solani AG1-IA group; confirms the AG-specific identity of the isolates (Matsumoto 2002). Amplification was not observed with AG1-IB, AG3 and AG2 specific primers (Khodayari et al. 2009). The selected four isolates were molecularly characterized by amplifying the internal transcribed spacer (ITS) and ribosomal DNA (rDNA) 5.8s regions by polymerase chain reaction using ITS1 and ITS4 primer pairs (White et al. 1990). The nucleotide BLAST (BLASTn) analysis of the resulting four sequences i.e. GenBank acc. no. MT105386, MT105387, MT105388, and MT105389 supported the identification of the isolates as AG-1-IA sub-group and showed 95.12%, 98.93%, 96.79%, and 98.04%, respectively, sequence homology with known cultures of R. solani AG1-IA isolated from rice in China (KC285893), and India (MK481078). To confirm pathogenicity, Sesbania plants were grown in pots and maintained in the greenhouse at 25℃ with a 12-h-light/dark photoperiod. After 35 to 40 days of growth, the stems of ten Sesbania plant were artificially inoculated with PDA plugs containing R. solani mycelia (Jia et al. 2007) and covered with aluminium foil. Plants inoculated with noncolonized agar plugs served as control. After 96 h of incubation, all the plants inoculated presented the typical collar and stem rot symptoms. No symptoms were observed in the control plants. R. solani was re-isolated cent percent from these ten infected plants fulfilling Koch's postulates. R. solani AG1-IA has been reported to cause sheath blight and banded leaf and sheath blight diseases of rice and maize, respectively (Ogoshi 1987). To our knowledge, this is the first report of Sesbania sesban infected by R. solani AG1-IA, and serve as a host for the pathogen. The result from our findings will be helpful for planning of crop rotations in an agro-ecosystem.

The use of plant materials as soil amendments is an uncommon practice amongst major farming communities in Ghana, although it is necessary for soil fertility improvement. An examination of the effects of soil amendments is necessary to encourage the use of under-utilized organic resources in Ghana. Thus, a field experiment was conducted using 8 different tropical plant materials mixed with chicken manure as soil amendments for growth of tomato as a test crop. The plant materials included Leucaena leucocephala, Centrosema pubescens, Sesbania sesban, Gliricidia sepium, Mucuna pruriens, Pueraria phaseoloides, Azadirachta indica, and Theobroma cacao. There were two other treatments: one with equivalent amounts of chemical fertilizers and the other with no-fertilizer input (control). Plant materials were mixed with chicken manure to obtain a uniform carbon-to-nitrogen (C:N) ratio of 5:1. Except the no-fertilizer control, all treatments received the same amount of nitrogen (N). To clarify the decomposition pattern of the plant materials in soil, an incubation experiment was conducted using only the plant materials before the field experiment. The Gliricidia treatment released significantly more mineral N than the other plant materials in the incubation experiment. However, the tomato fruit yield was not enhanced in the Gliricidia treatment in the field experiment. The known quality parameters of the tested plant materials, such as total N, total carbon (C), C:N ratio, and total polyphenols, had minimal effects on their mineralization dynamics. Azadirachta showed the best synergistic effect with chicken manure through significantly increasing soil microbial biomass and fruit yield of tomato. This result provides insights into the possible adoption of Azadirachta in combination with chicken manure as a soil amendment in small-scale agricultural holdings.

Sesbania sesban (L.) Merr is a perennial N2-fixing tree with high potential for use in agricultural production systems as a green manure and livestock forage. We studied the interactive effects of soil type and water level on the growth, biomass allocation, nutrient and mineral content of S. sesban. Four-week old seedlings of S. sesban were grown for 49 days (n = 5) in a factorial mesocosm set-up with six soil types (sediment, sand, alluvial, acid-sulfate, saline and clay) and three water levels (drained, water-saturated and flooded). The soils tested represent the predominant alluvial soil types of the Mekong delta, Vietnam. Sesbania sesban grew well with relative growth rates (RGR) around 0.08 g g−1 d−1 in all studied soil types, except the saline soil where plants died. In the low-pH (3.9) acid sulfate soil, that constitute more than 40 % of the Mekong delta, the RGR of the plants was slightly lower (0.07 g g−1 d−1), foliar concentration of calcium was 3–6 times lower, and concentrations of iron and sodium up to five times higher, than in other soils. The nutrient and mineral contents of the plant tissues differed between the soils and were also affected by the flooding levels. Foliar concentrations of nitrogen (50–74 mg N g−1 dry mass) and phosphorus (5–9 mg P g−1 dry mass) were, however, generally high and only slightly affected by water level. The results show that S. sesban can grow well and with high growth rates on most wet soils in the Mekong delta, except saline soils where the high salt content prevents establishment and growth. The nutrient and mineral contents of the plants, and hence the nutritional value of the plants as e.g. fodder or compost crops, is high. However, soil type and water level interactively affect growth and tissue composition. Hence, optimal growth conditions for S. sesban differ in the different regions of the Mekong delta.

This experiment was conducted to investigate effect of dried Sesbania sesban leaves supplementation on milk yield, feed intake and digestibility of Holstein Frisian X Zebu (Arado) crossbred dairy cows. Twelve cows at midlactation (155.83 ± 4.49 days of lactation), second parity, and 442.21 ± 3.40 kg average live body weight were randomly assigned to one of four dietary treatments according to a randomized complete block design. Cows were blocked according to their daily milk yield into three blocks of four animals each. Cows were fed a basal diet (control) or a basal diet supplemented with 1.25 kg/day dried Sesbania sesban leaves, 2 kg/day dried Sesbania sesban leaves and 2.75 kg/day dried Sesbania sesban leaves on a dry matter basis for 8 weeks. Total dry matter intake, nutrient intake, milk yield, dry matter digestibility, and nutrient digestibility showed significant variation among treatments. Cows supplemented with the highest level of Sesbania sesban (2.75 kg/day) had higher total dry matter and nutrient intake. Similarly, cows supplemented with 2 and 2.75 kg/day had higher milk yield than the nonsupplemented cows (up to 11.3 and 16.2%, respectively). Digestibility was lower for the nonsupplemented cows compared to cows supplemented with 2 and 2.75 kg/day dried Sesbania sesban leaves but statistically similar to the cows supplemented with 1.25 kg/day dried Sesbania sesban leaves. Supplementation with 2.75 kg/day Sesbania sesban resulted in higher organic matter digestibility (OMD) compared to the control. Crude protein digestibility (CPD), neutral detergent fiber digestibility (NDFD), and acid detergent fiber digestibility (ADFD) were significantly affected by Sesbania sesban supplementation. The nonsupplemented cows had lower CPD, NDFD, and ADFD. These results indicate that dried Sesbania sesban leaves supplementation to dairy increases total DM intake, digestibility, and milk yield.

Pot experiments were conducted to evaluate the damaging effects of salinity on Sesbania sesban plants in the presence and absence of arbuscular mycorrhizal fungi (AMF). The selected morphological, physiological and biochemical parameters of S. sesban were measured. Salinity reduced growth and chlorophyll content drastically while as AMF inoculated plants improved growth. A decrease in the number of nodules, nodule weight and nitrogenase activity was also evident due to salinity stress causing reduction in nitrogen fixation and assimilation potential. AMF inoculation increased these parameters and also ameliorated the salinity stress to some extent. Antioxidant enzymes like superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX) and glutathione reductase (GR) as well as non enzymatic antioxidants (ascorbic acid and glutathione) also exhibited great variation with salinity treatment. Salinity caused great alterations in the endogenous levels of growth hormones with abscisic acid showing increment. AMF inoculated plants maintained higher levels of growth hormones and also allayed the negative impact of salinity.

Antioxidants are found in many plants and can neutralize free radicals. Sesbania sesban (L.)Merr is a plant that has been used empirically by Indonesian people and its proven have many pharmacologycal activity. The objectives of this research were to study antioxidant activity Sesbania sesban leaves extract using DPPH (2,2-diphenyl-1-picrylhydrazyl) method and correlation with its total phenolic, flavonoid and carotenoid content. Extraction was performed by reflux using different polarity solvent. The extracts were vaporated using rotary evaporator. Antioxidant activity was tested using DPPH assay. Determination of total phenolic, flavonoid and carotenoid content were performed by UV-visible spectrophotometry and its correlation with inhibitory concentration 50 (IC50) DPPH scavenging activity were analyzed by Pearson’s method. Nhexane, ethyl acetate and ethanol extracts of Sesbania sesban leaves had IC50 DPPH  50 g/ml and it can be classified as very strong antioxidant. Ethanol extract of Sesbania sesban had the highest of total phenolic content (5.18 g GAE/100 g) and highest total flavonoid content (4.56 g QE/100 g), while the highest total carotenoid content (4.56 g BE/100 g) was given by n-hexane extract. Total phenolic content in Sesbania sesban leaves extracts had significant and negative correlation with their IC50 DPPH scavenging activities. Phenolic compounds in Sesbania sesban leaves extracts were contributor major in its antioxidant activities by DPPH method.

A pot experiment was carried out to assess Cd uptake and accumulation efficiency of Sesbania sesban. Plants were grown in soil spiked with 25, 50, 100, 150, 200, 250, and 300 mg/kg Cd. After 120 days, plants were harvested and analyzed for Cd content. A steady increase in Cd accumulation with increasing metal concentration in soil was observed for all treatments. Accumulation of Cd was greatest in roots (86.7 ± 6.3 mg/kg), followed by stem (18.59 ± 1.9 mg/kg), and leaf (3.16 ± 1.1 mg/kg). Chlorophyll content declined with increasing Cd concentration, while proline and protein content increased as compared to control. At higher Cd levels, root, shoot length, and biomass were all significantly reduced (p ≤ 0.001). An increase in total protein along with greater A250/A280 value suggested an increase in metal-protein complexes. Considering the rapid growth, high biomass, accumulation efficiency, and adaptive properties, this plant could be used as a valuable tool for the phytoremediation of Cd contaminated soils.

Chromium is one of the most common toxic metals present in the environment that induces various toxic effects in plants. A pot experiment was conducted to determine the effects of chromium on germination percentage, seedling growth, chlorophyll ‘a’, ‘b’ and proline content of Sesbania sesban (L.) Merr. The seedlings were treated with different concentrations of control, 0.10, 0.25, 0.50, 0.75 and 1.00 g kg-1 of chromium. The parameters such as germination percentage, root and shoot length, seedling fresh weight dry weight, chlorophyll ‘a’, ‘b’ and proline content of leaves were measured. Our results indicated that a significant inhibitory effect was observed at all levels of chromium compared to control. Increasing the concentration of chromium to 1.00 g kg-1 showed a significant decrease in seed germination, shoot and root length, fresh weight, dry weight and chlorophyll ‘a’ and ‘b’ content of plant. While proline, catalase and peroxidase contents were increased by increasing Cr concentration. It was also noted that accumulation of chromium in the roots was much higher than the shoots of the seedlings under treatment.

The use of advanced, effective and less toxic antimicrobial agents are required for the treatment of plant pathogens. In this study, hexane and ethanol extracts of two plants (Sesbania sesban and Cymbopogon citratus) and two algae species (Spirulina platensis and Scendusmus sp.) were screened for their antifungal and antibacterial activity on eight fungi (Rhizoctonia solani, Rhizopus stolonifer, Fusarium oxysporum, Aspergillus niger, Alternaria solani, Pythium debarianum, Botrytis cinerea and Penicillium digitatum) and two species of bacteria (Agrobacterium tumefaciens and Erwinia carotovora var. carotovora). Extracts of these plants and algae showed varied levels of antifungal and antibacterial activity. It was found that, the ethanol extracts of S. sesban plant and S. platensis alga had a high activity on tested fungi. On the other hand, the ethanol extracts of Scendesmus sp. alga and S. sesban plant showed the highest antibacterial activity against tested bacteria. The ethanol extract of S. sesban was the most potent fungitoxic extract against both A. niger and A. solani fungi with effective concentration (EC50) values of 0.135 and 0.011mg/L, respectively. On contrary, Scendesmus sp. ethanol extract revealed the highest inhibitory effect against E. carotovora var. carotovora bacteria. Conference Proceeding Full Paper Abbassy et al.; IJPSS, Article no. IJPSS.2014.10.014 1367

Sesbania sesban (L.) Merrill is the most productive multipurpose tree widely distributed in tropics and subtropics; and usually planted by smallholder farmers mostly for its fodder and soil improvement values. The objective of the present study was to review the various aspects (with emphasis on its importance) of S. sesban and generate comprehensive technical information for scholars who wish to study the plant in detail. Different parts ofS. sesban is reputed for various purposes such as weed control, phytoremediation, anti-inflammation and antioxidant effect, abortion and antifertility agent, antimicrobial activity, firewood source, livestock feed and pasture improvement, green manure, mosquito repellant, live support and Schistosoma control. Having these and other multiple uses, S. sesban can contribute to sustainable livelihoods by improving household food, nutrition and health security. Key words: Sesbania sesban, phytoremediation, anti-inflammation, antioxidant,livelihood.

The present meiotic study was carried out in 15 species of medicinal importance belonging to 14 genera and nine families. The chromosome numbers n=7 of Aloe vera L., n=10 of Brassica campestris Hook.f. & Thoms, n=12 of Capsicum annuum L., n=12 of Cissampelos pareira L., n=10 of Croton bonplandianum Baill., n=32 of Heliotropium eichwaldi Steud., n=7 of Hordeum vulgare L., n=7 of Lathyrus aphaca L., n=20 of Mazus rugosus Lour., n=7 of Pisum sativum L., n=6 of Sesbania sesban Merrill., n=12 of Solanum verbascifolium L., n=11 of Tephrosia purpurea Pers., n=6 of Vicia faba L. and n=6 of Vicia sativa L. has been observed. The course of meiosis has been found to be normal in all species except in somewhere chromosomal irregularities have also been observed. The medicinal plants are playing a very important role in our daily life. Besides their active role in every human requirement, they have proven to be the best source of various health care systems including traditional plant based medicines. Their huge importance reminds us about correct identification of various plant species, so that they can be use more accurately and effectively. Meiotic study is the tool that can support the plant identification. According to World Health Organization (WHO), about 80% of the world's population relying on plant based traditional medicines (Sivaperumal et al. 2010). This shows that all population communities are not able to afford the modern medical facilities. These people depend upon medicinal plants which are growing in their vicinity. This indicates that medicinal plants are not only providing raw material to the pharmaceutical industries but also cater the health care needs of the people, who could not afford other medical facilities. Chromosomal study is useful to understand the morphological diversity and genomic variation within a species (Stace 2000). Generally the researchers identify the plant species based on their morphological characteristics. The cytological analysis especially the study of chromosome number can further authenticate the identity of the plant species. Therefore present study has been conducted to determine the chromosome numbers and behavior in some medicinal plants to confirm the morphological characterization.

The reproductive performance of male livestock is of economic importance, and improving semen quantity and quality, especially for artificial insemination, additionally helps to avoid the loss of valuable genotypes. The review focuses on the impact of oxidative stress on sperm production and quality in livestock, and the potential role of plant based anti-oxidants to control this impact. From scientific reports dealing with livestock, the paper compiles evidence on effective dietary measures affecting sperm production and quality. Where little or no data are available on livestock, it refers to sources regarding other mammals, including man. The review concentrates on the use of distinct plants as feed supplements rather than on ways to treat deficiencies and imbalances in energy or macro- and micronutrients. Feeding of maca (Lepidium meyenii) and khat (Catha edulis) has been shown to positively affect sperm production and quality in animals. Some evidence points to favourable effects of leucaena (Leucaena leucocephala and Leucaena pallida), sesbania (Sesbania sesban), pomegranate (Punica granatum), tomato (Solanum lycopersicum) and amaranth (Amaranthus hypochondriacus) as well, but studies are either superficial or results are partially contradictory. Finally, the review considers the potential usefulness of medicinal herbs. The list of such plants includes Chinese herbs such as Lycium barbarum, Astralagus membranaceus, Acanthopanacis senticosi, Magnolia officinalis, Cornus officinalis and Psoralea corylifolia and the Indonesian plant Eurycoma longifolia. European candidate plants are Tribulus terrestris and Pendulum murex. Future research should include the screening of other plants, concentrating on the large number of plants rich in metabolites because of their presumed effectiveness. The modes of action often require clarification for the plants with demonstrated effects.

Sesbania sesban is one of the exotic multipurpose fodder trees introduced in the Ethiopian highlands for livestock feed and soil conservation. Several on-station studies showed that supplementation with Sesbania improved intake and digestibility of basal diet and growth rate of animals. However, information about farmers' feeding practices of Sesbania and farmers' perception of the effect of Sesbania feeding on animal performance is limited. The present study was conducted to assess farmers' feeding practices and their perception about effects of Sesbania supplementation on sheep performance in annual (one wheat-based (WheatCL) and one teff-based (TeffCL)) and perennial (coffee-based (CoffeeCL)) crop-based livestock systems in the Ethiopian Highlands. Data were collected from 98 households by interviews using a structured questionnaire. Farmers had on average 6.9 years of experience using Sesbania as a cut and carry supplementary feed. Farmers in the WheatCL and TeffCL fed Sesbania throughout the dry season while farmers in the CoffeeCL had no specific season for feeding Sesbania. Farmers in WheatCL and TeffCL offered significantly (P

Introduction: Antioxidants are micronutrients that have gained importance in recent years due to their ability to neutralize free radicals or their actions. Sesbania sesban (L) Merr is an ancient plant which is traditionally used as an antioxidant folklore plant. The present research deals with the phytochemical screening and in vitro evaluation of antioxidant activity of the leaves of Sesbania sesban (L) Merr. Methods: The ethanolic extract of the plant Sesbania sesban (L) Merr was subjected for the phytochemical screening. The preliminary screening reports the presence of Saponin, Tanin, Phenolic compound, Flavonoid in ethanolic extracts. DPPH scavenging activity or the Hydrogen donating capacity was quantified in presence of stable DPPH radical on the basis of Blois method. NO scavenging activity was performed in the presence of nitric oxide was generated from sodium nitroprusside and measured by the Greiss reaction according to the method of Marcocci. Ascorbic acid was used as standard for the both. Results: The scavenging was found to dose dependent. Thus extract has been established the as an antioxidant. The reducing capacity serves as significant indicator of antioxidant activity. The reducing power increased with the increasing concentration of sample. Conclusion: The folklore use of Sesbania sesban (L)Merr has been proved in present research work. Further studies along with isolation and molecular mechanism on extract of Sesbania sesban (L) Merr may lead to significant out come.

Chelate-induced phytoextraction is an innovative technique for cleaning metal- contaminated soil. The present study evaluates the degree of metal mobilization in soil and enhancement of phytoextraction of cadmium (Cd), lead (Pb), and zinc (Zn) by Sesbania sesban (L.) Merr. from artificially contaminated soil by application of ethylenediaminetetraacetic acid (EDTA). After 30 days of plant growth, the pots were divided into three sets (0.0, 2.5, and 5.0 mmol EDTA per kg soil). Experimental results indicated that levels of diethylenetriaminepentaacetic acid (DTPA)–extractable metals and metals in the leachate decreased as the EDTA dose increased. Plant growth parameters and total chlorophyll contents in the plants with EDTA applied were less than those of control. However, EDTA application significantly reduced metal accumulation in root and increased metal accumulation in the shoot of plants; similar results were obtained for the bioconcentration factor and translocation factor. The application of 5 mmol ED...

Preference for NH4+ or NO3− nutrition by the perennial legume Sesbania sesban (L.) Merr. was assessed by supplying plants with NH4+ and NO3− alone or mixed at equal concentrations (0.5 mM) in hydroponic culture. In addition, growth responses of S. sesban to NH4+ and NO3− nutrition and the effects on root nodulation and nutrient and mineral composition of the plant tissues were evaluated in a hydroponic setup at a range of external concentration of NH4+ and NO3− (0, 0.1, 0.2, 0.5, 2 and 5 mM). Seedlings of S. sesban grew equally well when supplied with either NH4+ or NO3− alone or mixed and had high relative growth rates (RGRs) ranging between 0.19 and 0.21 d−1. When larger plants of S. sesban were supplied with NH4+ or NO3− alone, the RGRs and shoot elongation rates were not affected by the external concentration of inorganic N. At external N concentrations up to 0.5 mM nodulation occurred and contributed to the N nutrition through fixation of gaseous N2 from the atmosphere. For both NH4+ and NO3−-fed plants the N concentration in the plant tissues, particularly water-extractable NO3−, increased at high supply concentrations, and concentrations of mineral cations generally decreased. It is concluded that S. sesban can grow without an external inorganic N supply by fixing atmospheric N2 gas via root nodules. Also, S. sesban grows well on both NH4+ and NO3− as the external N source and the plant can tolerate relatively high concentrations of NH4+. This wide ecological amplitude concerning N nutrition makes S. sesban very useful as a N2-fixing fallow crop in N deficient areas and also a candidate species for use in constructed wetland systems for the treatment of NH4+ rich waters.

SUMMARYNitrogen fixation by leguminous trees such as sesbania (Sesbania sesban) in acid soils is limited by aluminium (Al) toxicity and phosphorus (P) deficiency. We screened 214 East African sesbania accessions for Al toxicity tolerance, P use efficiency and sesbania–rhizobia symbiosis. Aluminium toxicity tolerance or sensitivity was measured by the relative root elongation index. Highly Al tolerant and sensitive accessions were screened for P use efficiency. Highly P use efficient and Al sensitive accessions were assessed for symbiotic effectiveness with acid tolerant rhizobia. Eighty-eight per cent of the accessions were Al toxicity tolerant. High Al levels reduced shoot P content by 88% and total dry matter (TDM) by 83%. P addition increased shoot P content and TDM. Rhizobia inoculation increased nodulation by 28–82%, shoot N content by 28–45% and TDM by 15–34% in the low rhizobia density acid soil of Bumala, Kenya. P use efficient accessions had higher nodulation, shoot N content and TDM in the ranges 32–70, 20–52 and 22–36%, respectively, compared to sensitive genotypes. The combination of sesbania accession (SSUG10) and rhizobia strain ASs48 was superior in shoot N accumulation. Inoculation of P use efficient germplasm with acid tolerant rhizobia can improve N-rich biomass accumulation suitable for N replenishment in acid soils.

Forty-six Rhizobium isolates from legume root and stem nodules were examined for their phosphate-solubilizing ability on Pikovskaya’s agar medium. Rhizobium isolates from root nodules of Cassia absus, Vigna trilobata and three strains from Sesbania sesban showed zone of tricalcium phosphate (TCP) solubilization. The isolate from C. absus showed maximum solubilization (620 μg/ml) after 12 d of incubation, while the Rhizobium sp. strain 26 (from S. sesban) showed the least amount (150 μg/ml) of phosphate solubilization. Among the carbon sources tested for their ability to solubilize TCP, maximum solubilization (620 μg/ml) was observed in glucose by Rhizobium isolate from C. absus. Phosphate solubilization increased with increase in glucose concentration steeply up to 2% and slowly above this concentration in four isolates. Among the nitrogen sources tested, maximum solubilization (620 μg/ml) was observed in ammonium sulphate by Rhizobium isolate from C. absus.

An extensive in vitro screening of various leaves, seeds and fruits of tropical multi-purpose shrubs and trees (MPT), leaves of medicinal plants and residues of leguminous food-feed crops was conducted to test their methane and ammonia generating potential. Plant materials were incubated with ruminal fluid/buffer mixture in four replicates for 24 h using the Hohenheim gas test method. In the group of the MPT leaves, different accessions of Acacia angustissima and Sesbania sesban were tested. Comparing the methanogenic potential, significant differences occurred both between and within the four plant groups tested. Generally, the methane-to-total gas ratio was lower for the leaves of the MPT and the medicinal plants than for the leguminous crop residues and the MPT seeds and fruits. Out of the latter group, Albizia rhizonse and Sapindus saponaria showed the lowest methanogenic potential. Within the MPT leaves the lowest methanogenic potential was found with Samanea saman and different Acacia and Sesbania species, plants known to contain plant secondary metabolites able to suppress methanogenesis. Differences between accessions of either Acacia angustissima or Sesbania sesban were large, illustrating the need to differentiate between accessions. The protozoal population was affected by the plant secondary metabolites to a smaller extent than expected, and leaves of Acacia angustissima and Sesbania sesban did not show any anti-protozoal effect. The plant group with the highest variation in their anti-protozoal effects was the MPT fruits and seeds with protozoal counts ranging between 0.6 and 5.7 × 10 4 /ml incubation liquid. Ammonia concentrations largely differed between and within the four plant groups with values ranging from 7 to 16, 10 to 33, 9 to 20, and 15 to 23 mmol/ml incubation liquid for the MPT leaves, for the MPT fruits and seeds, for the medicinal plant leaves, and for the leguminous food-feed crop residues, respectively. The correlation coefficient between plant crude protein content and ammonia concentration was as high as 0.75, indicating that plant secondary compounds such as tannins did not excessively inhibit feed protein degradation. In conclusion, various plant materials, including accessions of Acacia angustissima, Sesbania sesban and Cajanus cajan , were found promising to approach the goal of an improved nutrition of small ruminants in the tropics at simultaneously limited methane emissions.

Twenty six Rhizobium strains isolated from root nodules of Sesbania sesban were studied for chitinase activity on chitin agar plates. Among them, only 12 strains showed chitinase activity. The strain showing the highest chitinase activity was selected based on maximum clear zone/colony size ratio on chitin agar plates and chitinase activity in culture filtrate. The strain was identified as Rhizobium sp. which showed a high degree of similarity with Rhizobium radiobacter (= Agrobacterium radiobacter). The cultural and nutritional conditions were optimized for maximum chitinase activity. The Rhizobium sp. exhibited maximum chitinase activity after 36 h of incubation, at neutral pH. Among the different nutritional sources, arabinose and yeast extract were found to be good inducers for chitinase activity. Rhizobium sp. could degrade and utilize dead mycelia of Aspergillus flavus, Aspergillus niger, Curvularia lunata, Fusarium oxysporum and Fusarium udum.

Sesbania sesban (L.) Merr. (sesbania) is a fast growing N2-fixing widely used as an improved fallow species by smallholder farmers in eastern and southern Africa to restore fertility of their N-deficient soils. In order to establish the need for inoculation, the population of sesbania rhizobia in soil collected from a site where the species is intended for introduction was assessed using the most probable number (MPN) plant infection assay. The MPN of sesbania rhizobia was low (21, 6–81 fiducial limits at P=0.05 g−1soil) but with N2-fixation potential comparable to sesbania inoculant strain KFR 651. Evaluation of an indigenous sesbania rhizobial isolate GSS 1 from the MPN assay in potted field soil showed that it was more effective than strain KFR 651 in terms of plant growth and shoot dry matter (DM) accumulation at 9 and 12 weeks after planting, respectively. Total shoot N content was also higher for plants inoculated with isolate GSS 1 than inoculant strain KFR 651 and uninoculated control treatments 12 weeks after planting. These results demonstrate that it is better to inoculate with effective indigenous than exogenous rhizobia where the need for inoculation has been established.

We analyzed whether low calcium availability, as compared to high calcium availability, increased the accumulation of cadmium in Brassica juncea and Sesbania sesban. The cadmium uptake in the roots of both species was indeed increased, but not in the shoots. The translocation of Cd to the shoots is a complex process that seemed to be less affected by external ion concentrations and activities. As both species' viability was low under low calcium and high cadmium, the harvestable biomass limited the amount of Cd that could potentially be removed from polluted media by harvesting., Calcium (Ca) and the toxic heavy metal cadmium (Cd) are antagonistic ions competing for uptake in plants when they co-occur in soil solutions, and high Ca concentrations can reduce the uptake of Cd in plants. However, less is known about the effects of low Ca bioavailability on Cd uptake and translocation in plants. We hypothesized that low Ca availability would enhance Cd uptake and translocation in Sesbania sesban, a fast-growing shrub potentially useful for Cd removal from contaminated soils, and Brassica juncea, a well-known Cd-hyperaccumulator. The two species were grown under controlled conditions for 21 days in hydroponic nutrient solutions with either 0.2 or 2 mM Ca and 0 or 50 µM Cd in a 2 × 2 factorial experimental design. Both species had a lower relative growth rate, final root length and shoot and root biomasses at 50 µM Cd compared with growth without Cd. The negative effects of Cd on both species were exacerbated at low Ca availability. Brassica juncea had higher root Cd concentrations than S. sesban, but the shoot Cd concentrations did not differ between the two species. The low Ca concentration enhanced the uptake of Cd in the roots of both species, but Cd translocation to the shoots was low, especially at 0.2 mM Ca. We conclude that the low Ca concentration enhanced the uptake of Cd into roots of S. sesban and B. juncea and increased the phytotoxicity of Cd. The translocation of Cd to the shoots of the two species was, however, lower at 0.2 mM than at 2 mM Ca, implying that Cd removal from polluted soil cannot simply be increased by adjusting ion concentrations.

Green manure Sesbania sesban ( S. sesban ) and the nitrification inhibitor encapsulated calcium carbide (ECC) have been used to improve N supply and management in rice–wheat production systems in India. However, the ecological impact of combined use of these materials is largely unknown. We conducted a net-house pot culture experiment for 2 years, to investigate the effects of S. sesban and ECC on mineral N availability (NH 4 + and NO 3 – ), soil enzyme activities (dehydrogenase and nitrate reductase) and populations (MPN) of nitrifying organisms under a rice–wheat cropping system. Green manure S. sesban and ECC (+ECC or –ECC) were applied along with urea in various combinations to hybrid rice under flooded conditions. For wheat, it was urea alone or urea + ECC. Soil samples were studied at 10 days after top dressing, i.e. 40 days after rice transplanting and 35 days after wheat sowing, for above characteristics. The mineral-N in soil revealed the significant effect of combined use of S. sesban and ECC to enhance NH 4 + and total mineral-N (NH 4 + + NO 3 – ) contents. Dehydrogenase and nitrate reductase activities and population (MPN) of ammonia oxidizing bacteria (AOB) revealed a significant reduction in soils, whereas nitrite oxidizing bacteria (NOB) remained almost unaffected ( P > 0.05) in response to application of ECC with S. sesban and urea. Our results suggest that slow release of acetylene (C 2 H 2 ) from ECC has reduced ammonia mono-oxygenase with reducing population of AOB, and has the potential to retard the enzyme activities in favor of C and N conservations in a semi-arid agro-ecosystem.

A screenhouse experiment was conducted to evaluate the effects of inoculation with Meloidogyne javanica (uninoculated nematode control, low level [1000 eggs pot −1 ] and high level [10,000 eggs pot −1 ]) and rhizobial strains (uninoculated rhizobial control, strains KFR 647 and MBS1312) on nematode infection, nodulation and growth of Sesbania sesban (L.) Merr. (sesbania) provenances (Kisii and Kakamega). Heavy nematode infection of sesbania was noted for all three rhizobial inoculation treatments 2 months after sowing, and nodulation and plant growth were affected negatively at the high nematode inoculum level. Shoot dry weights showed negative and positive relationships with nematode infection (gall index) and number of effective rhizobium nodules, respectively. At 3 months, negative effects of the high nematode inoculum level on nodulation and plant growth were observed for rhizobial strain KFR 647 and the uninoculated control, but not for strain MBS 1312. Low nematode inoculum levels did not negatively affect nodulation or plant growth. The two sesbania provenances had similar growth at the high nematode inoculum level, but the Kisii provenance showed better growth than the Kakamega provenance at the low nematode inoculum level.

Presence of indigenous rhizobia nodulating promiscuous soyabean was determined in 92, mainly sandy soils, from wetter agro-ecological zones of Zimbabwe suited to soyabean production. A total of 129 isolates were obtained from nodules of promiscuous soyabean varieties, Magoye and Hernon 147, and a specific variety, Roan grown in potted soils. Magoye nodulated in 80%, Hernon 147 in 50% and Roan in only 25% of the 92 soils tested. Rhizobia populations ranged from undetectable to 2.4×10 4 cells g −1 of soil. Twenty-one of these isolates were tested for symbiotic effectiveness on two varieties, promiscuous Magoye and specific Roan. Differences in parameters such as nodule numbers, nodule weights and total N fixed reflected diversity among the indigenous isolates. Three isolates had significantly higher N 2 -fixing potential in comparison with the commercial strain MAR 1491 on promiscuous Magoye. Host ranges of 34 isolates were evaluated on nine legume species: Arachis hypogaea , Cajanus cajan , Crotalaria juncea , Glycine max , Macroptilium atropurpureum , Phaseolus vulgaris, Sesbania sesbania , Vigna subterranea , Vigna unguiculata . Of these 34 isolates, 33 formed nodules with M. atropurpureum of which 61% were moderately effective to very effective while all nodulated V. unguiculata with 58% being moderately effective to very effective. Twenty-eight isolates nodulated V. subterranea and C. cajan (short season variety) with 76 and 36% of these being moderately to very effective, respectively. None of the isolates formed nodules on Phaseolus vulgaris , Arachis hypogaea or Sesbania sesban . Our results indicate that the ability of even specific varieties of soyabean to nodulate with indigenous isolates in African soils is greater than generally assumed.

The diversity of 110 rhizobial strains isolated from Acacia abyssinica, A. seyal, A. tortilis, Faidherbia albida, Sesbania sesban, Phaseolus vulgaris, and Vigna unguiculata grown in soils across diverse agro-ecological zones in southern Ethiopia was assessed using the Biolog™ system and amplified fragment length polymorphism (AFLP) fingerprinting technique. By cluster analysis of the metabolic and genomic fingerprints, the test strains were grouped into 13 Biolog and 11 AFLP clusters. Twenty-two strains in the Biolog method and 15 strains in the AFLP analysis were linked to eight and four reference species, respectively, out of the 28 included in the study. Most of the test strains (more than 80% of 110) were not related to any of the reference species by both methods. Forty-six test strains (42% of 110) were grouped into seven corresponding Biolog and AFLP clusters, suggesting that these groups represented the same strains, or in some cases clonal descendants of the same organisms. In contrast to the strains from S. sesban, isolates from Acacia spp. were represented in several Biolog and AFLP clusters indicating the promiscuous nature of the latter and widespread occurrence of compatible rhizobia in most of the soil sampling locations. The results showed that indigenous rhizobia nodulating native woody species in Ethiopian soils constituted metabolically and genomically diverse groups that are not linked to reference species.

An experiment to assess the effect of different levels of Sesbania leaves on chemical composition, in vitro dry matter (DM) digestibility (IVDMD), in sacco rumen DM degradability (DMD), organic matter degradability (OMD) and crude protein (CP) degradability (CPD) of Napier grass–Sesbania mixtures was conducted. There were four Napier–Sesbania mixtures (100, 150, 200 and 250 g/kg of Sesbania on a DM basis) and Napier grass only (control) in a randomised complete block design. As the proportion of Sesbania increased in the mixture, there was an increase in CP, Ca and metabolizable energy, and a reduction in P, neutral detergent fibre (NDF), acid detergent fibre (ADF), cellulose and hemicellulose contents. The DMD, OMD, CPD and IVDMD increased as the proportion of Sesbania leaves increased. Results indicate that different levels of Sesbania forages have desirable characteristics as a potential feed supplement to improve the utilization of Napier grass to ruminant animals under tropical condition. Moreover, it could be concluded that nutrient content, IVDMD and ruminal DMD, OMD and CPD can be enhanced by feeding Sesbania with Napier grass, and it can be used in diet mixtures up to 250 g/kg of the DM fed.

A 6-month greenhouse pot trial was performed, aimed at screening appropriate Sesbania species for remediation of Pb/Zn and Cu mine tailings. Performances of young seedlings of four Sesbania species (S. cannabina, S. grandiflora, S. rostrata, and S. sesban) were compared with and without inoculation of rhizobia. Seedlings were planted in two types of tailings amended with garden soil or garden soil mixed with river sediment. The results indicated that inoculated plants generally produced a higher biomass than samples without inoculation. Pb/Zn mine tailings containing rather high concentrations of total and water-soluble Cu, Pb, and Zn were toxic to plant growth compared with Cu mine tailings, according to the growth performance of the four species. Sesbania sesban and S. rostrata showed superior growth performance, compared to the other two species. Thus, they can serve as pioneer species to modify the barren environment, by providing organic matter and essential nutrients such as nitrogen, upon decomposition, in a relatively short period of time. This is especially true for S. rostrata, which is an annual plant that forms both stem and root nodules. However, a longer-term field trial should be conducted to investigate if superior species can beneficially modify the habitat for the growth of subsequent plant communities.

The nodal and internodal explants excised from the orthotropic shoots of Sesbania sesban var. bicolor elicited the development of shoots directly from the explants as well as via an intervening callus phase on Nitsch (N) medium. On benzyladenine (BA) supplemented media, the adventitious shoot buds developed involving a callus phase. An average of 8.9 ± 4.1 shoots developed per nodal explant on N medium containing 0.5 mg dm−3 BA in 95 % cultures, whereas 65 % cultures of internodal explants developed shoots with an average of 5.9 ± 3.6 shoots per explant on N medium supplemented with 1.0 mg dm−3 BA. On kinetin (Kn) supplemented medium shoots developed directly from the surface of both the explants at all the concentrations tried. Nodal explants on N medium supplemented with 1.5 mg dm−3 Kn developed an average of 12.5 ± 7.9 shoots per explant in 100 % cultures, while internodal explants induced an average of 11.6 ± 7.4 shoots per explant in 75 % explants at 0.5 mg dm−3 Kn. The in vitro regenerated shoots developed roots when implanted on N medium supplemented with 2 mg dm−3 indole-3-butyric acid (IBA), after 30 d of inoculation. The in vitro developed plantlets were initially acclimatized under controlled conditions for four months, prior to their transfer to the field.

A survey was conducted in the food crop production area of western Kenya to characterise the nematode communities in different cropping systems and to monitor the effect of improved fallows on the abundance, diversity and community structure of plant-parasitic nematode assemblages. Soil samples were taken from short-term natural fallows ( 20 years), maize/beans cultivated fields and improved fallows with Crotalaria grahamiana , Sesbania sesban and Tephrosia vogelii . The Shannon diversity index and evenness were used to assess nematode diversity in the different cropping systems. The relationships between plant-parasitic nematodes and the soil physico-chemical properties were investigated with principal component analysis and co-inertia analysis. Planting trees/shrubs as improved fallows in croplands dramatically increased the populations of nematodes in the soil. However, the diversity of plant-parasitic nematodes was reduced. The distribution of plant-parasitic nematodes was correlated with that of some soil physical and chemical properties. Scutellonema spp. were dominant in the improved fallows where the highest values of magnesium and potassium were recorded. The plant-parasitic Dorylaimida ( Xiphinema spp. and Paratrichodorus minor ) were more abundant in the maize/beans plots and this abundance seemed related to high soil bulk density. Meloidogyne spp. and Rotylenchulus borealis had a strong positive correlation with soil organic matter and clay, and were abundant in the long-term natural fallows. The correlations between soil physico-chemical properties and nematodes indicate that, apart from the direct influence of the host plant, the soil characteristics play an important role in the abundance, distribution and structure of nematode communities. This validates the potential of nematodes as bio-indicator organisms of soil status.

Pot studies indicated that root-knot nematode ( Meloidogyne javanica ) infection reduces sesbania ( Sesbania sesban ) growth and planting methods modify the nematode damage, but their effects on sesbania biomass production at the field scale are not known. A field study was conducted in western Kenya for 2 yr, comparing direct seeding of sesbania with transplanting of bare-rooted seedlings in pure stands, with and without nematicide application in the field and in the nursery. In moist conditions, neither planting method nor nematicide had any influence on seedling survival and early growth. When early season rainfall was low and erratic, transplanted seedlings survived and grew better than seedlings from direct sowing, and nematicide application in the field and/or nursery improved seedling survival. Direct seeded sesbania had significantly less nematode galling and smaller nematode populations in the roots than transplanted sesbania. Both the establishment methods produced similar quantities of biomass, but direct seeded sesbania produced significantly greater biomass than the transplanted crop, if seedlings were already infected with nematodes in the nursery. Nematode infection on average reduced total sesbania biomass by 19%. Where sesbania cover crops have to be established by transplanting for socio-economic reasons, it is essential to use healthy seedlings free from nematodes for a good plant stand and early growth. Nematode-free seedlings can be produced on farms by at least one month of solarization of seedbeds. Neither field establishment method, nor nematicide application altered the soil nematode populations over a 12-month period. This means that the potential threat of increased Meloidogyne populations to nematode-susceptible crops following sesbania cover crops remains the same irrespective of how sesbania is established.

Samples of foliage from multipurpose leguminous trees (MPT) which had been selected as potential feed supplements for ruminants were examined for their chemical composition and in situ degradation characteristics, and were compared with alfalfa (Medicago sativa) hay and teff (Eragrostis abyssinica) straw. Organic matter (OM), acid detergent fibre (ADF), neutral detergent fibre (NDF), nitrogen, neutral detergent nitrogen, acid detergent lignin (ADL), soluble phenolics, NDF-bound proanthocyanidins and in vitro digestibility were determined in Acacia angustissima, Chamaecytisus palmensis (Tagasaste), Leucaena leucocephala, two cultivars of Sesbania sesban and Vernonia amygdalina (bitter leaf). The MPT all had a nutrient content, particularly in terms of N (up to 39.5 g available N per kg dry matter (DM)) similar to alfalfa hay, which would be suitable for supplementing teff straw, which had a high fibre, but low N (4.0 g available N per kg DM) content. In situ nylon bag digestion and in vitro gas production analyses were carried out to assess microbial degradation characteristics. The MPT were highly degradable in situ, however gas production in vitro decreased as the MPT:teff straw ratio increased in A. angustissima, indicating that antimicrobial components were present in this species. None of the chemical estimations were correlated with antimicrobial properties. It is concluded that some of the MPT tested may prove to be useful dietary supplements for ruminants receiving poor quality forages like teff straw, as has been found in other studies. However, chemical analysis alone will be of limited value in predicting the nutritive value of a new MPT which contains antimicrobial components or material toxic to the animal itself.

Nine different accessions of Sesbania sesban were examined for their toxicity to ciliate protozoa from sheep receiving a mixed grass hay–barley/fishmeal concentrate in Aberdeen, Scotland. Several accessions were much more toxic than those (ILRI 10865, ILRI 15036) identified and tested in a previous study. Two highly toxic accessions and one less toxic accession were compared with ILRI 15036 in a feeding trial in Debre Zeit, Ethiopia with sheep receiving a sululta hay–wheat bran diet. No suppression of protozoal numbers occurred in response to S. sesban supplementation (200 g/day). When rumen fluid removed from sheep on the supplemented diet was tested in vitro, protozoal activity appeared to be inhibited less by S. sesban in the mixed population than in either washed protozoa from the same rumen fluid or than had occurred in Scottish sheep. It was concluded that dietary, microbial or animal factors in the Ethiopian sheep had caused the destruction of the anti-protozoal material present in even the most potent accessions of S. sesban .

Nitrogen is normally the nutrient most limiting production of maize (Zea mays) — the main staple food crop — in southern Africa. We conducted a field study to determine the effect of N sources on soil nitrate dynamics at three landscape positions in farmers' fields in southern Malawi. The landscape positions were dambo valley or bottomland, dambo margin, and steep slopes. The N sources were calcium ammonium nitrate fertilizer applied at 120 kg N ha−1, biomass from Sesbania sesban, and no added N. Sesbania biomass was produced in situ in the previous season from sesbania relay cropped with maize. Nitrate in the topsoil (0 to 15 cm depth) increased to 85 days after maize planting (mean = 48 kg N ha−1) and then decreased markedly. Application of N fertilizer and sesbania biomass increased soil nitrate, and nitrate-N in topsoil correlated positively with amount of incorporated sesbania biomass. The strongest correlation between sesbania biomass added before maize planting and topsoil nitrate was observed at 85 days after maize planting. This suggests that the sesbania biomass (mean N content = 2.3%) mineralized slowly. Inorganic N accumulated in the subsoil at the end of the maize cropping season when N fertilizer and sesbania were applied. This study demonstrated the challenges associated with moderate quality organic N sources produced in smallholder farmer's fields. Soil nitrate levels indicated that N was released by sesbania residues in the first year of incorporation, but relay cropping of sesbania with maize may need to be supplemented with appropriately timed application of N fertilizer.

In eastern Zambia, nitrogen deficiency is a major limiting factor for increased food production. Soil fertility has been declining because of nearly continuous maize ( Zea mays) cultivation with little or no nutrient inputs. The use of short-duration tree fallows was one of several agroforestry options hypothesized to restore soil fertility. Sesbania sesban, an indige- nous N2-fixing tree was the most promising among species tested in screening trials. Several studies since 1987 have demonstrated the dramatic potential of two- or three-year sesbania fallows in restoring soil fertility and increasing maize yields. Analyses showed that these improved fallow systems were feasible, profitable, and acceptable to farmers. Results suggest that high maize yields following fallows are primarily due to improved N input and availability by the fallows. The potential to increase maize production without applying mineral fertilizers has excited thousands of farmers who are enthusiastically participating in the evaluation of this technology. The number of farmers who are testing a range of improved fallow practices has increased from 200 in 1994 to over 3000 in 1997. Presently, a strong network of institutions comprising government, NGOs, development projects, and farmer organizations is facilitating the adaptive research and expansion of improved fallow technology in eastern Zambia. Key elements in the research process that contributed to the achievements are effective diagnosis of farmers' problems, building on farmers' indigenous knowledge, generating several different fallow options for farmers to test, ex-ante economic analysis, farmer participation in on-farm trials, and development of a network for adaptive research and dissemination.

Seedlings of Brassica juncea, Sesbania sesban, and Oryza sativa exposed to salt stress accumulated proline to levels as high as 4- to 20-fold over those of controls. Because chloroplasts are the major site for synthesis of stress induced proline accumulation, in vitro studies were conducted to see how the over-accumulation of this solute influences the activity of the major chloroplastic enzyme Ribulose 1,5-bis-phosphate carboxylase (Rubisco) purified from the above plant species. Surprisingly, proline (believed to be a compatible solute) suppressed the activity of Rubisco significantly even when present at a concentration as low as 100 mM. The extent of this inhibition in Rubisco activity increased with an increase in the concentration of proline. Irrespective of the plant species from which Rubisco was purified, its activity declined by about 50% in the presence of 1 M proline. Rubisco from all three plant species was sensitive to NaCl and proline accelerated salt induced suppression in its activity. To the best of our knowledge this is the first report wherein a negative effect of proline (which is believed to protect enzymes under stress) has been clearly demonstrated. This perturbing effect of proline on Rubisco from higher plant species belonging to three distinct families cautions targeting of gene(s)/gene products for over-production of proline into chloroplasts.

Phenotypic diversity was studied among 13 Rhizobium strains selected from a total of 160 Rhizobium isolates from root nodules of Leucaena leucocephala. Two strains from Acacia saligna and two strains from Sesbania sesban plants were included in the examination for host range in the greenhouse. The Rhizobium sp. (Leucaena) strains were different from the reference strains and fell into three distinct groups for the utilization of 95 different carbon sources. Four of the best symbionts constituted a group, the majority of the strains fell into a second group, and strain DS 91 was the only member of the third group. Strains were effective symbionts for their original hosts. Nine strains were tolerant to elevated temperature (>42°C), and three strains were resistant to high salinity (>3% NaCl). All Rhizobium sp. (Leucaena) strains effectively nodulated L. leucocephala and L. culensii, but nitrogen fixation was greater with L. leucocephala than with L. culensii. These strains failed to form effective symbioses with two other species of Leucaena (L. retusa and L. divursiflora) or with alfalfa, Medicago sativa. Rhizobium sp. (Leucaena) strains DS 65, DS 78, and DS 158 nodulated and efficiently fixed nitrogen with Phaseolus vulgaris, with DS 65 showing the highest symbiotic capability. Strain DS 65 also nodulated and fixed nitrogen with Glycine max and Vigna sinensis. Nodulation of Leucaena by two Bradyrhizobium sp. (Acacia) strains was sparse. Strain DS 101 from Sesbania formed nodules on Leucaena, whereas the other strain from Sesbania, DS 110, failed to nodulate this genus.

Field experiments were conducted to study the effects of inoculation and application of P on the productivity of Desmodium intortum on an Ultisol and Sesbania sesban on a Vertisol, Alfisol and Ultisol in the Ethiopian highlands. On the Vertisol, the effect of drainage by using broad-bed-and-furrow technology was also investigated. In desmodium, inoculation had no significant effect (P > 0.05) on nodule weight, but application of P was found to be necessary for nodulation as plants did not nodulate without P fertilizer. Both inoculation and P significantly increased plant DM and N yields. Inoculation had no significant effect on nodulation, plant DM or N yields of sesbania in any soil. Probably because of previous P applications, P had no significant effect on sesbania plants grown on the Vertisol. On the Alfisol and Ultisol, sesbania responded differently to P applied in the nursery or field. On the Alfisol, P applied in the nursery increased nodule, root and shoot DM and root and shoot N yields, but P applied in the field increased only nodule DM. The reverse occurred on an Ultisol, where P applied in the nursery had no effect on sesbania, but P applied in the field increased nodule, root and shoot DM, root N yield, and root and shoot P yields. Drainage of the Vertisol increased shoot DM and N yields. It is apparent that P deficiency is an important limiting factor to the use of inoculation technology to increase legume productivity in the Ethiopian highlands.

Laboratory studies were conducted to investigate the partitioning of chloride (Cl) ions in the germinating seed of two forage legumes, Sesbania (Sesbania sesban) and Snail Medic (Medicago scutellata), under varied salinities and temperatures. Seeds were placed in Petri dishes containing 20 mL of saline solutions of varied electrical conductivities (0.01, 6.4, 12.2, 17.4, 22.6, 27.2, and 32.1 d/Sm) prepared with sodium chloride (NaCl). The germination temperatures were 10, 20, 30, and 40°C. Germination counts were taken every two days for eight days and the result was used to calculate germination rate index. On Day 8, seeds were separated into seed coat, cotyledon, and embryo, and analyzed separately for Cl. Generally, Cl concentration increased in the different seed components with increase in salinity and temperature. High Cl accumulation in the embryo was associated with germination failure. However, apart from the toxic effect of high embryo Cl content, high temperatures may also have a direc...

In two glasshouse studiesSesbania accessions were compared with a susceptible tomato cultivar as hosts toMeloidogyne javanica. Inoculating the growth medium with either infective juveniles or egg masses resulted in significant differences in root galling and egg mass production. The accessions could be grouped into moderate and poor hosts. Growth of roots was also depressed by the infestation. In a field study on a nematode infested site, significant variation in root galling was observed. Infestation was lower in plants growing on ridges than those on flat land. The studies indicate that continued cultivation ofSesbania may lead to a build up in soil root-knot nematode populations.

Above-ground biomass production in seedling and semi-mature individual plants of Sesbania sesban varieties were compared to non-destructive measurements of stem allometrics. The results indicate that measurements of stem characteristics (diameter and total height) are suitable for estimating biomass of S. sesban varieties and therefore useful in the selection of particular varieties for inclusion in short-rotation agroforestry systems in arid- and semi-arid regions. Less labour-intensive methods for accurately assessing the productivity of agroforestry species, such as the use of allometric regressions, could significantly increase the number of individual plants that could be screened in any particular trial. A multiple polynomial regression accurately estimated above-ground biomass in all plants ranging in age from six weeks to eighteen months (r2=0.99;p

Aluminium (Al) toxicity, phosphorus (P) deficiency and low rhizobia populations limit Sesbania (Sesbania sesban ) performance in tropical acid soils. The study determined the i) indigenous rhizobia populations that nodulate sesbania and ii) effects of lime (0 and 4 t/ha), P-fertilizer (0 and 60 kg/ha) and acid tolerant rhizobia (0 and inoculation) on soil and selected sesbania accessions performance in Western Kenya acid soil. Study site had acid soil, low available P, nitrogen (N) and rhizobia populations that nodulate Sesbania (146 cells/g soil). Lime increased soil pH, while both lime and P-fertilizer increased available P. Aluminium toxicity tolerant and P-efficient accessions (SSBSA004, SSUG3, SSUG4 and SSUG5) had faster growth, higher nodulation, shoot P, and shoot N and response to treatments than the sensitive one (SSBSA203). After 7 months of growth, SSUG3 had highest shoot length (306 cm) and dry matter (5.64 tons/ha), hence, most suitable for building poles and fuel wood. SSUG5 accumulated the highest shoot N (222 kg N/ha) and was therefore, most suitable soil N replenishment. Thus, in acid P deficient and low rhizobial population soils of Western Kenya, the use of lime, P-fertilizer, rhizobia inoculation and Al toxicity tolerant Sesbania are important for Sesbania establishment and growth. Key words: Rhizobia, Sesbania , soil acidity, aluminum toxicity, lime, phosphorus. INTRODUCTION Sesbania [Sesbania sesban (L) Merr ] is an important multipurpose tree legume that provides fuel wood, fodder for livestock and nitrogen (N)-rich biomass suitable for soil fertility replenishment. It is recommended for planting by smallholder farmers in the tropical regions of Eastern and Southern Africa, to correct soil N deficiency (Makatiani and Odee, 2007). In regions where farmers plant it, acid soils occupy 29 and 13% of the total land area in sub-Saharan Africa (SSA) and Kenya, respectively (Eswaran et al., 1997). In Kenya, most acid soils are found in the highlands East of Rift valley and