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This experiment was conducted to study the effects of supplementation of seaweed-based formulation (SWBF) on performance of lactating Murrah buffaloes. Eighteen lactating Murrah buffaloes were divided into 3 groups (T0, T1 and T2) based on their body weight, parity, days in milk and milk yield following randomized block design. Two SWBF were tested; SWBF-I was combination of two tropical red seaweed species namely Kappaphycus alvarezii) and Gracilaria salicornia, whereas SWBF-II was combination of the two red seaweeds and one brown seaweed species Turbinaria conoides. All the animals were fed to meet their requirements (ICAR 2013). Animals in control (T0) group were fed concentrate mixture, Hybrid Napier fodder and wheat straw without any supplemental seaweed. However, SWBF-I and SWBF-II were supplemented at 2.5% of the concentrate feed of groups T1 and T2, respectively. Intake and apparent digestibility of nutrients, plasma concentrations of selected metabolites, enzymes and hormones were similar among the groups. A tendency of decreased (P=0.060) plasma concentration of cortisol was observed in treatment groups. Total antioxidant capacity was improved (P=0.001) due to SWBF supplementation; the best response was observed in group T2, followed by T1. Concentration of lipid peroxides decreased (P

The biological treatment of lignocellulosic biomass through enzymatic hydrolysis serves as an ecofriendly and cost efficient method. As these biomass is the most abundant renewable resource which lacks proper utilization and disposal. This study was conducted to isolate and screen the presence of cellulosic enzymes from the microbes of natural ecosystem under laboratory condition. The microbes were isolated from elephant dung, forest soil, termites (gut) collected from Anaikatty forest range of Coimbatore district. Microbes were screened qualitatively and quantitatively for the presence of endoglucanase, exoglucanase, β-glucosidase enzymes. Among the total microbes recovered, one bacteria (BT4), one action bacteria (AS3)and two fungal isolates(FE5,FE6)showed maximum cellulolytic efficiency during qualitative screening, those were further subjected for quantitative estimation of endoglucanase, exoglucanase, β-glucosidase activity.

Agricultural soils are responsible for formation of N2O through nitrification and denitrification processes. Nitrification inhibitors reduces the rate at which ammonium is converted to nitrate either by killing or interfering with the metabolism of nitrifying bacteria. Synthetic nitrification inhibitors can efficiently inhibit nitrification. The present study was undertaken to observe the effect of Potassium thiosulfate (PTS) and neem coated urea on N2O efflux under irrigated tomato cultivation to assess its suitability for decreasing N2O emission to the atmosphere. The results depicted the reduction of nitrate nitrogen on third day after fertilizer application compared to zeroth day. The decreased NO3-N was mainly due to the uptake by tomato for its growth and converted into N2O as intermediate product during nitrification process. The yield of tomato (fruit yield) was significantly increased due to the application of various doses and types of N fertilizer application along with N inhibitors. The highest yield (63.2 t ha-1) was recorded with the soil application of nutrients in STCR based recommendation of NPK with Neem coated urea which was on par with the STCR based recommendation of NPK with Normal urea (183:160:125kg ha-1) along with Potassium thiosulfates @ 1% of applied N whereas blanket recommendation of NPK application recorded lower yield. The 38% lowest N2O emission was found in the STCR based recommendation of NPK with Normal urea with Potassium thiosulfates @ 1% of applied N compared to Blanket recommendation of NPK with Normal urea, which was on par with the treatment of STCR based recommendation of NPK with Neem coated urea.

An infra red thermographic analysis of well watered control and well watered heat stressed pearl millet (Pennisetum glaucum) was conducted at ICAR – Central Research Institute for Dryland Agriculture as a part of high resolution phenomics studies to identify the individual quantitative physiological parameters by plant phenotyping that form the basis for more complex abiotic stress tolerant traits. It was seen that the temperature gradient increased gradually from ground level to the top in the control non heat stressed plant. In contrast, it was seen that in the heat stressed plant the temperature increased up to the middle of the plant and then started to decrease at the top of the plant in comparison with the non heat stressed control plant. Our results indicate that the lowering of temperatures in the top of the heat stressed plant may be a mechanism by which the heat stressed plant acclimates to stress by regulating its transpiration thereby bringing in a cooling effect to counter stress.

The conversion of atmospheric CO 2 into stable long lived carbon pools is an important phenomenon of soil carbon sequestration. Cocoa cultivation significantly increased the slow and passive carbon pools of soil. Significant increase in the organic fractions like humic acid, fulvic acids, non-humic and humin were observed in seven years cocoa cultivated soils. The organic matter fractions were significantly high during January and there after a decrease in trend were registered for all the three soils. A field study was carried out in the cocoa plantations of Moorje, Bantwal taluka, Dakshinakannada district, Karnataka. This study was carried out in five and seven years cocoa plantations in comparison with non-cocoa plantations.

Shoot-tip derived callus cultures of Sorghum bicolor were transformed by Agrobacterium tumefaciens as well as by bombardment methods with the mutated pyrroline-5-carboxylate synthetase (P5CSF129A) gene encoding the key enzyme for proline biosynthesis from glutamate. The transgenics were selfed for three generations and T4 plants were examined for 100 mM NaCl stress tolerance in pot conditions. The effect of salt stress on chlorophyll and carotenoid contents, photosynthetic rate, stomatal conductance, internal carbon dioxide concentration, transpiration rates, intrinsic transpiration and water use efficiencies, proline content, MDA levels, and antioxidant enzyme activities were evaluated in 40-day-old transgenic lines and the results were compared with untransformed control plants. The results show that chlorophyll content declines by 65% in untransformed controls compared to 30–38% loss (significant at P < 0.05) in transgenics but not carotenoid levels. Photosynthetic rate (PSII activity) was reduced in untransformed controls almost completely, while it declined by 62–88% in different transgenic lines. Salinity induced ca 100% stomatal closure in untransformed plants, while stomatal conductance was decreased only by 64–81% in transgenics after 4 days. The intercellular CO2 decreased by ca 30% in individual transgenic lines. Malondialdehyde (MDA) content was lower in transgenics compared to untransformed controls. The activities of superoxide dismutase (SOD; EC 1.15.1.1), catalase (CAT; EC 1.11.1.6) and glutathione reductase (GR; EC1.8.1.7) were quantified in leaves exposed to 100 mM NaCl stress and found higher in transgenics. The results suggest that transgenic lines were able to cope better with salt stress than untransformed controls by protecting photosynthetic and antioxidant enzyme activities.

Studies were conducted to estimate the impact of increase in temperature on number of generations of tobacco caterpillar, Spodoptera litura on peanut for seven different locations of various agro ecological zones of the country for baseline (1961 to 1990), present (1991 to 2005), near future (2021 to 2050) and distant future (2071 to 2098) climate change (A1B) scenarios. The daily minimum and maximum temperature (MinT and MaxT) records were used to obtain cumulative degree days (DD) for each generation of insect using a temperature threshold of 10°C. Faster accumulation of degree days will making it possible for one or two additional generations with shortened life cycle (completion of generation would be 5 to 6 days earlier) of S. litura was inferred for both near and distant-future climate change scenarios (CCS) compared to baseline and present periods, at all locations. The additional number of generations and variation in the generation time of S. litura across seven growing locations of India imply the definitive and differential impacts, respectively of the projected increasing temperature in the future CCS. Key words: Arachis hypogaea, climate change scenario, degree days, generation time, number of generation, Spodoptera litura.

Among the effects of impending climate change, drought will have a profound impact on crop productivity in the future. Response to drought stress has been studied widely, and the model plant Arabidopsis has guided the studies on crop plants with genome sequence information viz., rice, wheat, maize and sorghum. Since the value of functions of genes, dynamics of pathways and interaction of networks for drought tolerance in plants can only be judged by evidence from field performance, this mini-review provides a research update focussing on the current developments on the response to drought in crop plants. Studies in Arabidopsis provide the basis for interpreting the available information in a systems biology perspective. In particular, the elucidation of the mechanism of drought stress response in crops is considered from evidence-based outputs emerging from recent omic studies in crops.

Agricultural productivity is affected worldwide due to anthropogenic and climate change-induced abiotic stresses, posing a threat to food security. Use of microorganisms for abiotic stress management in agriculture is emerging as economically viable and environmental-friendly option. Actinomycetes, the Gram-positive bacteria with filamentous structure that are common associates of plants (as rhizosphere inhabitants and as plant endophytes), are receiving attention for their potential application in stressed ecosystems. Many actinomycetes exhibit plant growth-promoting (PGP) properties including indole acetic acid (IAA) production, phosphate solubilization, siderophore production, biocontrol of phytopathogens, and 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase activity. Besides, they can grow under diverse stress conditions such as moisture stress, high temperature, salinity, alkalinity, and wide pH range. Recently, many reports have documented the role of actinomycetes in alleviating salinity and drought stress in crop plants. However, there is a need to further strengthen the research to explore their potential to improve plant productivity under diverse environmental stress conditions by conducting extensive pot and field trials and to understand the underlying mechanisms.

Sunflower ( Helianthus annuus L.) and maize (Zea mays L.) were chosen as C 3 and C 4 crop plants and assessed for the impact of enhanced CO 2 (700 ppm) and its interaction with drought stress in open top chambers (OTCs). The ameliorative effect of higher CO 2 concentration (eCO 2 ) under drought stress was quantified. It is interesting to note that the C 3 crop responded significantly and positively with eCO 2 under both well-watered and drought stress treatments for root: shoot ratio while C 4 crop showed a better response only with the drought stress environment. Root volume showed a positive significant response with CO 2 concentration enhanced over ambient level and the increment in root volume was 146% and 340% in sunflower and maize crops, respectively. The leaf water potential, stomatal conductance and transpiration showed a decreasing trend in both the crops with drought stress and eCO 2 showed an ameliorative effect leading to higher P n rates in sunflower crop under drought stress treatment. The findings reveal that improvement of root traits is worth attempting for the future crop behavioral responses under eCO 2 and drought stress environments. The study confirmed the beneficial effect of eCO 2 in maize and sunflower by ameliorating the adverse affects of drought stress.

Sorghum bicolor L. Moench cv. SPV462 was transformed with the mtlD gene encoding for mannitol-1-phosphate dehydrogenase from E. coli with an aim to enhance tolerance to water deficit and NaCl stress. Transgene (pCAM mtlD) integration and expression were successfully confirmed by PCR, Southern, RT-PCR and Western analysis. Segregation analysis based on germination of T0 seed on hygromycin-supplemented medium revealed an expected Mendelian ratio 3:1 in lines 5, 72 and 75. Retention of leaf water content was remarkably higher in transgenic leaf segments when exposed to polyethylene glycol 8000 (−2.0 MPa), as compared to the untransformed controls. Another significant finding is that the transgenics maintained a 1.7 to 2.8 fold higher shoot and root growth, respectively, under NaCl stress (200 mM) when compared to untransformed controls. These results demonstrate that engineering mannitol biosynthetic pathway into sorghum can impart enhanced tolerance to water deficit and salinity.

A study was conducted to analyse the association of osmotic adjustment (OA) with drought tolerance and yield in castor (Ricinus communis L.). Hybrids (GCH4, DCH32 and DCH177) and their respective parents (VP-1, 48-1, LRES17, DCS5, DPC9 and DCS9) were assessed for their osmotic adjustment, leaf water relations, accumulation of compatible solutes in relation to seed yield in response to moisture stress at primary spike development stage. OA increased with increasing stress period up to 33 days and the increase was more rapid in the high OA (HOA) genotypes. HOA genotypes also had higher leaf RWC and ELWRC and maintained higher leaf water potentials (Ψl) compared to LOA genotypes under water deficit. Genotypes with HOA accumulated greater levels of proline, total soluble sugars (TSS), total free amino acids (FAA) and potassium than those with LOA in response to water deficit. Contribution of TSS was the maximum (61%), compared to FAA (17%), proline (12%) and potassium (2.8%) to the Ψs at 33 days after imposing water deficit indicating that sugars were the major contributors towards OA in castor leaves. A positive relationship existed between OA of expanded leaf 33 days after imposing stress (r = 0.8539) and total seed yield under water-limited conditions in various castor genotypes tested and HOA genotypes had higher total seed yield than genotypes with LOA. Genotype variability exists for OA and it is a heritable trait in castor. Hybrids followed their superior parents in terms of OA. HOA genotypes of castor produced significantly higher seed yield than LOA genotypes. Accumulation of TSS contributed largely to the OA in castor.

The response of blackgram ( Vigna mungo L. Hepper) to two levels of elevated carbon dioxide (550 and 700 ppm) in terms of growth and yield was investigated and compared with ambient CO 2 level (365 ppm) using open-top chambers. The growth parameters viz., length and weight of root and shoot, root:shoot ratio, leaf area and weight significantly increased at 700 ppm CO 2 when compared with 550 ppm. The percentage increase in total biomass at 700 and 550 ppm CO 2 was 65.4% and 39%, respectively compared to the ambient (chamber) control. The increase in total seed yield at 700 ppm (129%) was due to an increase in number of pods per plant and 100 seed weight, whereas at 550 ppm (88.7%) it was due to an increased number of pods/plant and seeds/pod. The results indicate variable responsive effects at different levels of CO 2 emphasizing the pertinence of research on elevated CO 2 in various agroecological inhabitations all over the world. The indication of higher responses for root and leaf at initial growth stages at the higher elevated level of CO 2 (700 ppm), which leads to better root establishment, achieving early photosynthetic efficiency and also better biomass production, and its improved partitioning can be reckoned as a positive aspect of increasing concentrations of CO 2 in atmosphere. The harvest index increased significantly to 35.7 and 38.4% at 550 and 700 ppm, respectively; it is a very important phenomenon in pulses for breaking the yield barrier.

An efficient and rapid regeneration protocol was developed using shoot apices from germinating seedlings of two cultivars of sorghum, SPV-462 and M35-1, as explants. A vertical slit given from the base of each dissected apex enhanced the efficiency of callusing response by two fold. MS medium containing 0.5 mg dm−3 each of 2,4-D and kinetin was most effective in producing friable and embryogenic calli. Scanning electron microscopy of these calli detected somatic embryogenesis. Calli thus induced gave rise to approximately 42 green shoots per callus in both the genotypes when transferred to regeneration medium containing 1.5 mg dm−3 kinetin.

The bacterial betA gene for biosynthesis of glycinebetaine was transferred to cabbage (Brassica oleracea var. capitata) cultivar 'Golden Acre' through Agrobacterium-mediated transformation of hypocotyl explants. Transgenic status was established through Southern hybridization and mRNA expression in the shoots. The transformants exhibited higher tolerance to NaCl stress compared to untransformed parent plants. In physiological assessment of salinity tolerance, transgenics showed better growth response and greater stability in maintaining plant water relations at increasing levels of salinity. These results demonstrate that engineering glycinebetaine biosynthetic pathway into cabbage can lead to enhanced salt tolerance.

The relationship between high temperature stress injury and temperature dependence of the transverse relaxation time (T2) of leaf water was examined using NMR in four cultivars of wheat differing in their sensitivity to high temperature stress. The T2declined with increasing temperature between 25 and 35 °C. A comparison of relative injury based on electrolyte leakage and T2, between 40 and 50 °C, indicated that while membrane permeability increased with increasing temperature there was an increase in T2until 44 and 48 °C in susceptible and tolerant cultivars respectively, followed by a sharp decline. This pattern of change in T2with increasing temperature was consistent whether the same or different samples were used for each treatment temperature. Loss of temperature dependence of T2after heat killing indicated irreversible changes in T2, probably due to the loss of membrane integrity. Heat tolerant varieties, which suffered less membrane injury, had a higher T2compared to susceptible varieties. Tolerant varieties also maintained the T2of leaf water protons to higher temperatures than did sensitive varieties. This NMR-based, non-invasive, rapid technique could be used to efficiently detect heat injury in leaf tissues.

The effect of leaf removal on sink expression was studied in a heterotic hybrid (CM119×CM120) of maize and its parents CM119 and CM120 to understand the physiological basis of yield heterosis. Leaf removal treatments were imposed by excising 0, 33, 66 and 100% leaves above the cob at silking. The hybrid had a significantly higher biomass and kernel yield, kernel number per square metre and 100 kernel weight compared to its parents with all leaf removal treatments. The kernel yield showed a highly significant linear relationship with the leaf area index at silking in all the genotypes. The final kernel number at harvest appeared to be tightly controlled by the leaf area available. Leaf senescence pattern after anthesis differed for the treatments and was lowest in the hybrid as compared with the female and particularly with the male parent. An analysis of cob characters revealed that the female parent had a higher number of florets per row compared to the male parent at silking, whereas the male parent was better than the female parent in the ratio of filled kernels to the florets. The hybrid followed the better parent in both characters.

Water stress effects on accumulation of dry matter, carbon and nitrogen in grains were analysed in varieties and species of wheat differing in yield stability. Variable water environments were generated using a line source sprinkler system. Although large fluctuations occurred in the water potentials of the flag leaf and ear, grain growth remained relatively buffered under moisture stress. Developing grains were at a lower moisture level throughout grain growth in plants subjected to moisture stress relative to the unstressed plants. Carbon content decreased more than the nitrogen content in the stressed grains of the species and varieties. Reduction in the duration of grain growth and the rate of dry weight accumulation induced by water stress was more prominent in T. aestivum var. C306 and T. sphaerococcum . Grain yield was reduced significantly under water stress, the maximum being in the high yielding cultivar HD2329. Both grain number and grain weight were reduced in response to stress, the extent of reduction being different in different genotypes.

The pattern of free NH 4 + accumulation and its metabolism was studied during the growth and development of field-grown wheat cv. HD 2204 at two applied N levels viz. 30 and 120 kg ha -1 . The study was confined to the 3rd, 5th and flag leaf blades and the developing ears, borne on the main shoot, during their ontogeny. The NH 4 + levels were considerably lower in young leaves and increased sharply as the leaves senesced when the activity of glutamine synthetase (GS) declined. In contrast to GS, glutamate dehydrogenase (GDH) remained active even during senescence. Concentrations of protein, free amino acid and total reduced N declined with age in the leaves. An assessment of free NH 4 + pool, free amino acid content and the activity of GS and GDH in the floral parts revealed that glumes, awns and grains also were active sites of NH 4 + turnover. Higher applied N level not only increased leaf and grain N concentration but also led to higher free NH 4 + levels in leaves and in developing ears. Presence of NH 4 + in the entrapped transpirate revealed that NH 4 + is released from both leaves and ears during senescence.

Unpredictable drought affects growth and yield of dryland cowpea (Vigna unguiculata [L.] Walp.) during rainy season. With the objective of identifying compensatory growth responses after relief of water stress, pot-grown plants (cv. C-752) were water-stressed at flowering, and physiological responses, short term dry matter partitioning upon relief of water stress, and productivity at maturity were studied. Water stress decreased, to varying degrees, leaf water potential, stomatal conductance, photosynthesis rate and transpiration rate. Recovery in assimilation lagged behind that in water relations. Assimilate supply seemed to be limiting early pod growth upon relief of water stress due to low photosynthesis rate, reduced leaf area per pod, and increased partitioning to leaf expansion. However, later pod growth was not limited by assimilate supply and final dry matter per pod was similar in both non-stressed and stress-affected plant. Cowpea exhibited the following growth responses during pod-fill stage upon relief of water stress: 1. increase in leaf area, 2. shift in dry matter partitioning in favour of leaf expansion, 3. extended green leaf duration, and 4. increase in pod number. These partially compensating physiological responses probably ensure reasonable productivity of dryland cowpea during rainy season.

Nodulation and N2 (C2H2) fixation processes were studied in cowpea and groundnut during water stress and recovery. In plants relieved from water stress, leaf water-potential recovered much faster than nitrogenase activity in both species. The recovery ability depended on the intensity of water stress. Nitrogenase activity recovered much faster in groundnut than cowpea, even from a relatively higher level of stress. This was partly due to the lack of nodule shedding in groundnut, while severe shedding of nodules in cowpea did not permit the recovery of activity, particularly at higher stress levels. Leghemoglobin was found to be more stable in the nodules of groundnut than cowpea. Water stress led to an accumulation of total soluble sugars in groundnut nodules, while there was no change in cowpea. The recovery pattern of nitrogenase activity in these two crop species is discussed in relation to the nodule morphology, biochemical response and the differences in stress response at the whole plant level.

The effect of water deficit on nodulation, N2 fixation, photosynthesis, and total soluble sugars and leghemoglobin in nodules was investigated in cowpea and groundnut. Nitrogenase activity completely ceased in cowpea with a decrease in leaf water potential (ψ leaf) from −0.4 MPa to −0.9 MPa, while in groundnut it continued down to −1.7 MPa. With increasing water stress, the acetylene reduction activity (ARA) declined very sharply in cowpea, but ARA gradually decreased in groundnut. Even with mild water stress (Δψ leaf of 0.2 MPa), nodule fresh weight declined 50% in cowpea partly due to a severe nodule shedding whereas nodule fresh weight declined in groundnut only whenψ leaf decreased by 1.0 MPa. No nodule shedding was noticed even at a higher stress level in groundnut. Photosynthesis and stomatal conductance were also more stable in groundnut than in cowpea under water stress. There was a sharp increase in total soluble sugars and leghemoglobin in the nodules of groundut with water stress, but no definite trend could be found in cowpea.

Physiological responses of pearl millet and sorghum to water stress were compared for better understanding of crop adaptation in drylands. Pearl millet (MBH-110) and sorghum (CSH-6) were raised in pots and were subjected to short term water stress at anthesis stage. Water stress decreased leaf water potential, rates of stomatal conductance, photosynthesis and transpirations and transpiration efficiency in flag leaves relatively more in sorghum than in pearl millet. Stomatal conductance and transpiration rates recovered quicker in pearl millet than in sorghum in 24 h after rewatering. Dry season accentuated the water stress effects. Transpiration efficiency of pearl millet was more responsive to increase in atmospheric moisture. The physiological responses explain the better adaptation of pearl millet to drier regions than of sorghum.

Glutamine synthetase activity was found to be several fold higher in the leaves of a few C3 as compared to C4 plants. Differences in NH4+ levels were marginal. Methionine sulphoximine inhibition of glutamine synthetase resulted in increased in NH4+ levels more in wheat than in sorghum. The decrease in methionine sulphoximine induced accumulation of free NH4+ by photorespiratory inhibitors, isonicotinic acid hydrazide and α-hydroxy methane pyridine sulphate was also several fold higher in wheat than in sorghum. Feeding of glycine and glycolate, intermediates of photorespiration, showed the presence of active glycine decarboxylation system in sorghum but the metabolism of glycolate was more efficient in wheat. Higher glutamine synthetase activity in C3 plants may be a necessary adaptation to a higher photorespiratory NH4+ production and explain the similar or higher N losses in C4 as compared to C3 plants. These results also support the hypothesis that glutamine synthetase is important in the assimilation of photorespiratory ammonia.