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Aerobic rice cultivation has gained recognition for resource conservation and ecosystem services. However, aerobic/partially-aerobic rice productivity is often constrained by several deficiencies in soil-plant system including phosphorus (P), because of reduced soil P dissolution and crop P acquisition. The study aimed to design sustainable P management option(s) for non-flooded rice [system of rice intensification (SRI)]-lentil system in an alkaline Fluvisol by evaluating the effect of system-based sole fertilizer-P and integrated P management treatments on crop yields, soil P dynamics, P pools, soil biophysical and biochemical attributes. The treatments consisted of one control and three variable seasonal distribution sole fertilizer-P treatments [subscript value (kg P ha−1)] in non-flooded rice (SRI)-lentil (L) rotation ([SRI0-L0], [SRI22-L22], [SRI33-L11], [SRI11-L33]), three integrated P management treatments ([SRI11-L11+phosphate solubilizing bacteria (PSB)], SRI16.5-L5.5+rice residue incorporation (RR)+PSB, SRI5.5-L16.5+lentil residue incorporation (LR)+PSB)]. Besides this, a conventional flooded rice-lentil system with the recommended sole fertilizer-P rate ([PTR22-L22]) as a treatment was evaluated to compare soil P dynamics in flooded versus non-flooded rice ecologies. Soil P availability was significantly reduced (7–8%) in the non-flooded rice compared to the flooded rice ecology. The integrated treatment involving suboptimal fertilizer-P rate (22 kg P ha−1y−1), rice residue recycling, and PSB increased soil P availability in rice (5-6%) and lentil (9-10%) seasons as well as system productivity by 8.3% over the recommended sole fertilizer-P treatment ([SRI22-L22], 44 kg P ha−1y−1). The rice residue recycling integrated treatment increased NaHCO3-Pi (11%) and dissolved non-reactive P (6%) over the recommended sole fertilizer-P treatment. The positive effects of the lentil residue recycling integrated treatment on soil P availability and crop yields were relatively lower than the rice residue recycling integrated treatment possibly because of the lower residue C-input. Correlation results indicate that microbial biomass carbon, soil aggregation and labile organic carbon have a positive influence on P availability in this alkaline soil. The significant positive correlation between the active C-pool and total dissolved non-reactive P suggested that oxidisable C input could improve bioavailable P forms. Results indicated the role of balanced P fertilization in C-stabilization, which had the lowest in the P control treatment. The study with one soil type suggested that in-situ crop residue recycling integrated P management (rice residue in particular) could be a sustainable option for improving P bioavailability, nutrient cycling, and productivity of non-flooded rice-legume system in tropical alkaline soil, but, for the validation of the results, more studies with diverse soil properties are warranted.

Deterioration of soil physical quality and depletion of soil organic carbon (SOC) are widespread challenges in tropical rice–wheat growing regions. Consequently, soil productive capacity, production sustainability, and resource use efficiency have declined in this agro-ecosystem. Ecological engineering approach such as legume inclusion in cropping system offers several ecosystem services, and thus, may serve an important role in the restoration of soil health. Given that, a long-term (2003–2015) field experiment was conducted to assess the impact of four rice-based crop rotation treatments [rice–wheat, rice–chickpea, rice–wheat–mungbean, rice–wheat–rice–chickpea] each with three levels of nutrient management treatments [control, integrated nutrient management, chemical fertilizers] on soil aggregation, soil carbon pools, and carbon stabilization. Legume inclusive rotations increased water stable macro-aggregates (WSMA) over rice–wheat rotation in both surface (0–0.2 m) and subsurface (0.2–0.4 m) soil depths. In surface soil, WSMA was the highest in rice–wheat–mungbean rotation (65%) followed by rice–chickpea rotation (57%) and was the least in rice–wheat rotation (50%). Subsequently, grain legume inclusive rotations had the higher aggregate ratio and mean weight diameter over rice–wheat rotation, being the highest in rice–wheat–mungbean rotation. Rice–wheat–mungbean and rice–chickpea rotations had higher carbon concentration in coarse macro-aggregates, meso-aggregates, and coarse micro-aggregates as compared with rice–wheat rotation. Grain legume inclusive rotations increased active carbon pool (9–18%), SOC (6–17%), and carbon management index (5–7%) over rice–wheat rotation, and the order was rice–wheat–mungbean > rice–chickpea ≥ rice–wheat–rice–chickpea > rice–wheat. Integrated nutrient management treatment resulted in higher macro-aggregate (7%), mean weight diameter (6%), active carbon pool (22%), passive carbon pool (16%), SOC (20%), and carbon management index (22%) over the chemical fertilizer treatment. Thus, it is concluded that inclusion of grain legume in lowland rice-based rotation and integrated nutrient management could improve soil aggregation, carbon concentration in aggregates, and soil carbon pools in the tropical soils. The study highlights the prospects of strategic designing of legume inclusive rotation/s for rice agro-ecosystem health and its sustainability.

Introduction The aim of the study was to enumerate the clinical, hematological, and molecular spectrum of G6PD deficiency in malaria endemic regions of south west Odisha. Methods Diagnosis of G6PD deficiency was made by using the Di-chloroindophenol Dye test in two south west districts (Kalahandi and Rayagada) of Odisha State. Demographic and clinical history was taken from each individual using a pre-structured questionnaire. Molecular characterization of G6PD deficiency was done using PCR-RFLP and Sanger sequencing. Results A total of 1981 individuals were screened; among them, 59 (2.97%) individuals were G6PD deficient. The analysis revealed that G6PD deficiency was more among males (4.0%) as compared to females (2.3%). Prevalence of G6PD deficiency was significantly higher among tribal populations (4.8%) as compared to non-tribal populations (2.4%) (p=0.012, OR=2.014, 95%CI=1.206-3.365). Twenty four individuals with G6PD deficiency had mild to moderate anemia, whereas 26 G6PD deficient individuals had a history of malaria infection. Among them, 3 (11.5%) required blood transfusion during treatment. Molecular analysis revealed G6PD Orissa as the most common (88%) mutation in the studied cohort. G6PD Kaiping (n=3), G6PD Coimbra (n=2) and G6PD Union (n=1) were also noted in this cohort. Conclusion The cumulative prevalence of G6PD deficiency in the present study is below the estimated national prevalence. G6PD deficiency was higher among tribes as compared to non-tribes. Clinical significance for G6PD deficiency was noted only in malaria infected individuals. Rare G6PD Kaiping and G6PD Union variants were also present.

The root induced changes in soil chemical and biological properties of five winter pulses (rajmash, fieldpea, lathyrus, lentil, and chickpea) were examined in mild-alkaline soil (pH ~ 7.8). Rhizospheric acidification was common in all pulses, and chickpea resulted in maximum reduction in rhizospheric pH in (4.8%). The resulted acidification substantially influenced the rhizospheric nutrient availability and scale of increase was highest for available-P. The relative changes for different nutrients followed the sequence P (37.4%) > Zn (35.8%) > Fe (32.4%) > N (18.4%) > S (17.5%). However, the available K did not differ significantly. Soil biological indicators like microbial biomass carbon (C) and fluorescein diacetate were enhanced by 63–243.5 and 9.8–36.3%, respectively over the bulk soil. Likewise, improvement in soil organic C was also evident. The rhizospheric soil had higher passive C-pool indicating pulses can improve soil resistant C-fractions, which persists for a longer time. Among the pulses, chickpea had the maximum rhizospheric alteration and thus distinguished as most potential winter pulse crop under the mild-alkaline soil.

Chickpea (Cicer arietinum L.) is a dominant pulse crop in the world for its climate resilience and nutritional values. Weed infestation causes a significant yield loss in chickpea and jeopardize in realizing the potential yield across regions. Pendimethalin as pre-emergence (PRE) is the ruling herbicide, however, post-emergence (POST) herbicides are limited in this crop particularly for managing broad-leaved weeds and higher yield gain. We assessed the impact of POST herbicides available in different crops on weed phytotoxicity, crop selectivity and yield performance in chickpea on sandy-loam soil of Kanpur, India. The experiment was undertaken for two consecutive years (2016-17 and 2017-18) comprising nine herbicides, besides unweeded control (UWC) and weed-free check (WFC). Among the herbicides tested, halosulfuron-methyl 70 g a.i. ha−1 and tembotrione 100 g a.i. ha−1 showed the maximum phytotoxicity scale of 5-10 on chickpea. Clodinafop-propargyl + sodium-acifluorfen 122.5 g a.i. ha−1 and imazethapyr + imazamox 70 g a.i. ha−1 had a recoverable phytotoxicity (scale 3–5) on chickpea. Topramezone 20.6 g a.i. ha−1 at 25 days after sowing (DAS) resulted in higher phytotoxicity on weeds (toxicity scale of 7–10) without any phytotoxicity on chickpea. It significantly controlled the dominant broad-leaved weeds: Chenopodium album L., Lepidium didymum L., Spergula arvensis L., Medicago polymorpha L. and Fumaria parviflora Lam. compared to the remaining herbicides. Topramezone reduced total weed density by 68-70% and 48–51% (P ≤ 0.05) at 45 and 95 DAS compared with UWC, respectively. Therefore, this herbicide had higher (P ≤ 0.05) weed control efficiency in both years (89.8% in 2016-17 and 76.5% in 2017-18) than remaining treatments. Topramezone increased 15.3-19.6% chickpea seed yield than the recommended herbicide pendimethalin 1000 g a.i. ha−1 - quizalofop-p-ethyl 100 g a.i. ha−1 without affecting the nodulation and fluorescein diacetate activity. The UWC resulted in 64% (mean of two years) yield loss compared to the WFC in chickpea. Importantly, topramezone gave comparable yield with WFC. Hence, topramezone can be safely used in chickpea for managing broad-leaved weeds and realizing higher productivity.

Aerobic rice is gaining global recognition for its role in the conservation of water. However, its productivity is often constrained by several deficiencies in the soil-plant system. Particularly, in absence of flood-induced phosphorus (P) desorption, it is likely that P availability in aerobic soils would be reduced thus affecting the productivity. Presently, our understanding of soil P dynamics and its bioavailability in aerobic rice-based system(s) is limited, particularly in alkaline soils. In this study, the impact of sole fertilizer and integrated P management on soil P dynamics, biochemical and biophysical properties and crop yields in direct-seeded rice (DSR)-lentil rotation in alkaline soil was assessed to devise sustainable management option(s). Seven different P treatments in aerobic direct seeded rice-lentil system [subscript value (kg P ha−1)] i.e., P control (P[0−0]), three sole fertilizer-P treatments with variable rate application to component crops (P[22−22], P[33−11], P[11−33]), and three integrated treatments ([P11−11+ phosphate solubilizing bacteria (B)], [P16.5−5.5+ rice residue recycling (RR)+B], [P5.5−16.5+lentil residue recycling (LR)+B]) in aerobic direct seeded rice-lentil system along with a conventional flooded rice-lentil system with the recommended fertilizer-P rate (P[22−22]FR) were studied. Given the recommended sole fertilizer-P rate, the aerobic rice soil (P[22−22]) had lower available-P (8–10 %) compared to the flooded rice soil (P[22−22]FR). The rice residue recycling integrated treatment (P16.5−5.5+RR + B) increased soil available-P in both the rice (5–6 %) and lentil (12–13 %) crop season over the recommended sole fertilizer-P treatment (P[22−22]), and also increased the system productivity by 6–7 %. The higher NaHCO3-Pi (13 %) and dissolved non-reactive P (DNRP) (7%) in the treatment P16.5−5.5+RR + B over the treatment P[22−22] suggested a higher soil P mobilization potential of rice residue recycling integrated treatment. The effect of lentil residue recycling integrated treatment (P5.5−16.5+LR + B) and recommended sole fertilizer-P treatment P[22−22] was similar on soil P and crop yields, and would thus be an option when considering the reduction of P fertilizer use in aerobic rice. Soil aggregation, very-labile carbon, microbial biomass carbon, DNRP exhibited positive correlations with P bioavailability in the aerobic rice soil. Our results suggested that C-stabilization in aerobic rice soil is altered with P input, the lowest rate being recorded in the control treatment. Hence, the study concluded that reduced soil P availability could limit the productivity potential of aerobic rice-lentil system in alkaline soils, and integrated treatments involving in-situ crop residue recycling (rice in particular) and suboptimal fertilizer rate could improve soil P bioavailability, soil quality parameters, and crop yields, thus, recommended for sustainable management.

Chickpea faces an extended period of critical weed competition due to its slow initial growth and requires sequential herbicide application to obtain maximum yield. However, no post-emergence herbicides are available especially for controlling broad-leaved weeds. Post-emergence herbicides like topramezone, imazethapyr + imazamox and clodinafop-propargyl + Na-acifluorfen for their phytotoxicity and bio-efficacy was evaluated in chickpea. Phytotoxicity of imazethapyr + imazamox 60 g a.i./ha on chickpea was prolonged and crop recovery was poor. On the contrary, phytotoxicity on crop due to topramezone 40 and 60 g a.i./ha and clodinafop-propargyl + Na-acifluorfen 500 g a.i./ha was minimal (rating 6). Significantly lower (P ≤ 0.05) weed population by 66.2 and 54% were recorded in topramezone 60 g a.i./ha and clodinafop-propargyl + Na-acifluorfen 500 g a.i./ha, respectively, over unweeded control at 65 DAS, besides significant reduction in dry weight of weeds. The WCE and WCI were higher in topramezone 60 g a.i./ha (71.6%) at 65 DAS and in clodinafop-propargyl + Na-acifluorfen 500 g a.i./ha at 95 DAS, respectively. Moreover, these had an edge over two hand weeding and quizalofop ethyl 50 g a.i./ha (recommended post-emergence herbicide) in chickpea. Treatments topramezone 40 g a.i./ha and clodinafop-propargyl + Na-acifluorfen 500 g a.i./ha recorded significantly (P ≤ 0.05) higher grain yield by 26.4 and 20.1% over quizalofop ethyl 50 g a.i./ha. Therefore, topramezone and clodinafop propargyl + Na-acifluorfen could be an option for controlling the diversified weed flora particularly broad-leaved weeds like Chenopodium album, Melilotus alba, Medicago denticulata and others in chickpea.

Rice and wheat are the main crops of the eastern part of Uttar Pradesh. Butachlor and 2,4-D are the two herbicides, which are very popular among rice growers. Studies on the estimation of herbicide residues present in the soil of rice and wheat grown in sequence were undertaken through bioassay technique. Results revealed that butachlor 1.5 kg/ha pre-emergence applied in rice did not leave its residue in the soil of rice after harvest. Isoproturon 1.0 kg + 2,4-D sodium salt 0.5 kg/ha at 30–35 days of sowing wheat also did not leave residue in the soil. In another long-term trial in rice-chickpea cropping system, butachlor 1.5 kg/ha pre-emergence and anilofos 0.5 kg/ha pre-emergence applied in rice did not leave their residue in the soil of rice.

Flooding is common in rainfed lowland areas of the world. Several physiological and biochemical plant processes were affected by the flooding, which causes deprivation of O2 in the root zone. Hence, a study was undertaken with four rice varieties, viz., Sita, IR64, FR-13A and Bharani, grown in simulated tanks and subjected to submergence stress. The effect of anti-GA compound paclobutrazol on the recovery of plants including gas exchange, chlorophyll fluorescence and grain yield parameters were measured after submergence stress. Net photosynthesis rate declined in plants subjected to stress at seedling stage. Varieties FR-13A and IR 64 recorded higher photosynthetic rate than Bharani and Sita. However, paclobutrazol application enhanced photosynthesis and transpiration rate in all the varieties after the imposition of stress. Chlorophyll fluorescence parameter, viz., maximum quantum yield of PSII (Fv/Fm) declined under stress at panicle initiation stage in all four varieties. The decline in yield of PSII was less in FR-13A, followed by Bharani and IR 64. Moreover, decline in panicle weight and grain weight was observed in all the varieties under submergence stress; however decline was less when the plants were treated with paclobutrazol. Higher photosynthetic rate coupled with lesser decline in yield of PSII with paclobutrazol application increased the tolerance of variety towards submergence stress. Hence, paclobutrazol application alleviated the negative effect of transient submergence stress by contributing to the recovery of plants and maintenance of yield in rice.

Fourteen rice genotypes comprising of land- races, high yielding varieties (HYVs) carrying Sub1 allele as well as without Sub1 allele contrasting in their tolerance to submergence stress were evaluated for plant survival, growth and yield response under submergence stress during kharif season of 2011 and 2012. Decline in yield was observed almost in all the rice genotypes grown under submergence stress as compared to control condition. Under short term submergence, rice genotypes carrying Sub1 allele survived complete submergence up to 14 days, whereas genotypes without Sub1 did not survive signifi- cantly and gave very low yield. The decline in yield in rice genotypes under stress (submerged) condition ranged from 1.5 to 97 %. Under control condition HYVs with and without Sub1 allele showed non significant differences in grain yield, but showed an average yield advantage of more than 2.5 t ha -1 over landraces. Non significant difference were observed in landraces for grain yield under submer- gence and control treatments indicating considerable sub- mergence tolerance. Landraces and HYVs carrying Sub1 showed higher survival percentage after submergence than the susceptible parents and check variety IR 42. Variance studies revealed significant differences among genotypes for yield attributing traits. Correlation studies revealed that genotypes with the capacity to maintain higher biomass, higher chlorophyll and higher starch and sugar concentra- tions after submergence had higher survival of seedling and grain yield. Present study suggested that submergence tolerance related genes from landraces like Atiranga, Gangasuili and Kalaputia apart from FR 13A need to be identified for introgression into HYVs for successful exploitation of low lying flood prone ecosystem.

Objectives were to (1) determine the feasibility of performing hoof biopsies without impairing locomotion; (2) evaluate the feasibility of using biopsied tissue for quantitative PCR; and (3) compare relative gene expression among claws for several target genes. Biopsies were performed on 6 Holstein cows, yielding 4 tissue specimens per cow from front leg, right limb, and medial claw (claw position 3); rear leg, left limb, and lateral claw (claw position 5); and rear leg, right limb, medial claw (claw position 7). Cows were monitored for lameness daily for 7 d post-biopsy and then weekly for 8 wk. Histopathological analysis confirmed that tissue collected was from between the stratum corneum and dermis. Biopsied tissue was used for RNA extraction, including evaluation of yield and purity. The profile by claw position of 19 genes with key functions in cell differentiation, proliferation, inflammation, and keratin formation was assessed via quantitative reverse transcription-PCR. Other than transient disturbances in locomotion score in some cows during 2 to 4 d post-biopsy, no signs of pain, locomotion impairment, or clinical lameness were observed post-biopsy. Total RNA yields averaged 259.7±100, 447.8±288, and 496.4±118μg/mg of tissue for claw positions 3, 5, and 7, respectively. The biopsy procedure was successful for obtaining corium for gene expression. Among 5 keratin proteins analyzed, only keratin 5 was expressed. Transcripts related to inflammation and oxidative stress ( STAT3 , MYD88 , SOD2 , and TLR4 ) were among the more abundant in corium tissue, but expression did not differ between claws. Biotinidase ( BTD ) expression was greater in claw 3 versus claw 5, whereas the ligand-activated nuclear receptor retinoic acid receptor-α ( RXRA ) was greater in claws 3 + 5 compared with claw 7. Overall, results from this pilot study revealed modest differences at the transcriptome level, suggesting that biotin availability and lipid metabolism differ between claw positions, whereas inflammation and oxidative stress seem to play an important role across claws. More comprehensive studies of the hoof transcriptome are required to improve our understanding of the mechanisms that link environmental and dietary factors to development of lameness.

Because of the large surface area and common occurrence of smectites in the clay fractions, they are important in sorption/desorption reactions of organic pollutants entering soils and sediments. Results of sorption and desorption of atrazine by Al- and Ca-saturated smectite reported here showed that Al-saturated smectite sorbed much higher amounts of atrazine than Ca-saturated smectite. Al-saturated smectite sorbed 3820 mg kg (super -1) as compared to 1902 mg kg (super -1) by the Ca-saturated smectite during 5 consecutive sorptions from 10 ppm atrazine solution. Sorption isotherms over 2-10 ppm atrazine concentration range were nonlinear in all cases. Freundich coefficients, K f , obtained from the sorption isotherms were much higher for Al- than Ca-saturated smectite; K f varied from 405 to 3035 for Al-saturated and 100 to 306 for Ca-saturated. The pH values of Al- and Ca-saturated smectites were 3-4 units higher than the pK a (1.68) of atrazine, which suggests that atrazine was sorbed as neutral molecules. Stronger H-bonding between the more polarized H 2 O associated with the trivalent Al ion than the divalent Ca ion is likely responsible for the greater sorption by Al-smectite.

The damping capacity of stir-cast aluminium-matrix composites containing graphite and silicon carbide particles, were studied using a cantilever beam specimen and an HP 5423A Structural Dynamics Analyser. Damping data were determined in the first mode of vibration. Aluminium-matrix composites containing 5–10 vol % graphite particles and 10 vol % silicon carbide particles were prepared by the stir-casting technique and die cast to obtain standard samples (6 mm×25 mm100 mm). Graphite particles were found to be more effective in enhancing the damping capacity of composites compared to silicon carbide particles. The damping capacity of composites increased with the volume percentage of graphite within the range studied. However, no notable improvements in damping capacity were observed by dispersion of silicon carbide in aluminium alloy. The results have been analysed in terms of the effect of size, shape, nature and volume fraction of particles on the damping capacity of the aluminium matrix particulate composites and compared with the damping capacity data available in the literature. The effects of frequency, strain amplitude, temperature and processing on damping capacity of the aluminium matrix composites are reviewed.

Recent cloning and sequencing studies suggest that heavy chains of all non-muscle myosins II have a protein kinase C (PKC) phosphorylation site within their tail regions. A fragment of human macrophage myosin heavy chain, encompassing its COOH-terminal 396 amino acids (MIIAF46), was expressed in Escherichia coli to provide a model system for study of PKC-mediated phosphorylation. PKC phosphorylated this fragment when phosphatidylserine (PS) liposomes were present, but not when liposomes made from PS/phosphatidylcholine (PC) were used. The reaction required Ca2+, but not other activators such as diacylglycerol (DG) or phosphatidylinositol 4,5-bisphosphate. Phosphorylation of MIIAF46 was not observed in the presence of micelles of PS or PS/DG. Similar results were obtained using native myosin II purified from bovine brain and chicken intestine brush border. Phosphorylation of light chains, in contrast, occurred even with PS/PC liposomes if DG was present. Addition of the PS and PS/DG liposomes significantly increased the turbidities at 340 nm of MIIAF46 and native myosin II, and the extent of increase depended upon the type of myosin used. Also, PS and PS/DG liposomes shifted the gel filtration elution positions of MIIAF46 and myosin II. In contrast, liposomes of PS/PC and PS/PC/DG gave only a slight increase in turbidity with all myosins and fragments and did not noticeably shift their gel filtration elution positions. These results suggest that myosins II bind to PS liposomes via the COOH-terminal regions of their heavy chains with affinities specific to each myosin isoform, that the binding is dependent upon the PS composition, and that PKC phosphorylates the PS-bound heavy chains.

The problem of free convection flow of a viscous heat generating rarefied gas is considered for the case when a strong magnetic field is imposed perpendicularly to the plane of flow. Analytical expressions for the velocity field and temperature are obtained and the influence of the Hall currents m and the heat source parameter δ on the velocity field and temperature are discussed

The ozone layer acts like a giant sunshade, protecting forests and other life forms on the Earth's surface from much of the Sun's harmful ultraviolet radiation. The depletion in stratospheric ozone layer due to anthropogenically released pollutants such as CFCs during the last few decades has resulted in increased UV radiation at ground level. UV radiation (100-400 nm) consists of UV-C (100-280 nm), UV-B (280-315 nm) and UV-A (315-400 nm) radiations. Out of these three, UV-B radiation has a disproportionately large photobiological effect on forest tree species. Enhanced UV radiation affects the tree species by modifying both their biological and biochemical environment. Damage may occur in a number of ways including the direct destruction of genetic material DNA at molecular level, disruption of membranes and other cell structure and generation of highly reactive chemicals known as "free radicals". It also inhibits various physiological processes including photosynthesis, nutrient assimilation, chlorophyll and protein synthesis, which results into reduced growth and development of the tree as a whole. Enhanced UV radiation especially UV-B radiation leads to several biochemical changes in the plants and synthesize secondary metabolites (condensed tannins, phenolics, flavonoids etc.) in the leaves and other parts of the plant. These secondary metabolites are synthesized as an adaptive mechanism in trees against enhanced UV radiation and have UV-absorbing properties. It reduces the insect herbivory, several viral and fungal diseases of a tree. Elevated CO2 concentration ameliorates the damaging effects of UV radiation, whereas, drought in combination to enhanced UV radiation has inhibitory effect on plant growth and development. The inhibitory effects of enhanced UV radiation on the tree growth and development are more pronounced in the trees grown at the higher altitudes and at the equator as compared to the trees grown at lower altitude and at higher latitude. Trees undergo several changes to overcome the damaging effects of increased UV radiation by expressing new genes, synthesizing UV-absorbing compounds (secondary metabolites) and reactive oxygen trees are able to tolerate UV radiation stress.

VAM spore population was studied under degraded, least degraded and undegraded forest soils with an objective of assessing the influence of soil degradation on VAM spore distribution at two soil depths, surface layer (0–20 cm) and sub-surface layer (20–40 cm). Physico-chemical properties of soils in all the three sites were also studied. The increase in degree of soil degradation caused a reduction in VAM spore population at both the soil layers of the three sites. Highest VAM spore population was recorded from the undegraded site followed by least degraded and degraded sites respectively. There was a reduction in VAM spore population of up to 70 per cent in the degraded site and 30 per cent in the least degraded site in comparison to the undegraded site. The VAM populations in soils were positively correlated with soil moisture content (P=0.01), water holding capacity (P=0.01) and pH (P=0.05) in the case of surface soil layer. Bulk density was negatively correlated with the VAM spore population at the surface (P=0.05) and sub-surface soil layers (P=0.01). Altogether five genera (Acaulospora, Entrophospora, Glomus, Gigaspora, and Scutellospora) having forty-four species were recorded.

The use of mixed-ligand (iodide and thio­cyanate) coordination with cobalt has led to the crystallization of the title compound, (C24H20As)2[CoI2(NCS)2]. The structure comprises tetra­hedral (C6H5)4As+ cations and tetra­hedral [CoI2(NCS)2]2− anions, the latter lying on crystallographic twofold axes.

Use of mixed-ligand (bromide and thiocyanate ions) coordination with nickel has led to the crystallization of the title compound, (C24H20As)2[Ni(NCS)2Br2]. X-ray crystal structure analysis reveals that the asymmetric unit contains one (C6H5)4As+ cation and one half [Ni(NCS)2Br2]2− anion, the latter lying on a crystallographic twofold axis.

Suitable techniques were developed under greehnouse conditions to determine mechanisms of resistance to a leafhopper Empoasca dolichi (Paoli) by utilizing field resistant and susceptible varieties of cowpea, Vigna unguiculata L . (Walp.). Results on adult leafhopper preference indicated no significance among any of the 6 varieties tested. Fecundity studies indicated considerable varietal differences; varieties TVu 662, TVu 59, TVu 123, and TVu 4557 showed a significantly lower development of early and late stage nymphs in comparison to TVu 1190E. The basis of resistance in variety TVu 1190E was due to tolerance. All resistant varieties were significantly less damaged due to feeding by adults and 1st instars. The relative growth rate of 5th instars was highest on the susceptible variety TVu 76. Fifth instars caged on resistant varieties TVu 59, TVu 662, and TVu 123 were significantly less in weight, probably due to antibiosis. Resistant variety TVu 123 appeared to show a low survival of 1st and 5th instars. Leafhoppers reared on the resistant variety TVu 123 were more susceptible to insecticide dimethoate than those reared on the susceptible variety, TVu 37. The basis of resistance in variety TVu 123 is attributed to antibiosis.

In aqueous potassium nitrate the complexes Cu(dip)(gly) Cl. 1.5 H2O, Cu(dip)(alan) Cl. 1.5 H2O, Cu(dip)(val) Cl.3 H2O, Cu(dip)(ser) Cl H2O have been observed to undergo single step two electron irreversible electroreduction at dme. From the characteristics of irreversible wave, the rate constant kr for each complex has been calculated at reference potential −0.2142V vs sce. It is observed that the electroreduction of the complexes Cu(dip)(gly) Cl.1.5 H2O, Cu(dip)(alan) Cl. 1.5H2O does not follow a particular reaction mechanism with temperature. It has been also observed that the half-wave potential shifts towards more negative side as the ligand field band shifts to higher energy side. A correlation between electrode behaviour characteristics and spectral characteristics has been attempted. A possible electron transfer mechanism has been suggested on the basis of orientation of orbitals towards the electrode. The stability constant data obtained from the literature also support the proposed mechanism.

Infrared spectra of the adducts of quinoline with are reported and discussed. Assignments are given for the important bands.