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Unpredictable weather vagaries in the Asian tropics often increase the risk of a series of abiotic stresses in maize-growing areas, hindering the efforts to reach the projected demands. Breeding climate-resilient maize hybrids with a crosstolerance to drought and waterlogging is necessary yet challenging because of the presence of genotype-by-environment interaction (GEI) and the lack of an efficient multi-trait-based selection technique. The present study aimed at estimating the variance components, genetic parameters, inter-trait relations, and expected selection gains (SGs) across the soil moisture regimes through genotype selection obtained based on the novelmulti-trait genotype-ideotype distance index (MGIDI) for a set of 75 tropical pre-released maize hybrids. Twelve traits including grain yield and other secondary characteristics for experimental maize hybrids were studied at two locations. Positive and negative SGs were estimated across moisture regimes, including drought, waterlogging, and optimal moisture conditions. Hybrid, moisture condition, and hybrid-by-moisture condition interaction effects were significant (p = 0.001) for most of the traits studied. Eleven genotypes were selected in each moisture condition through MGIDI by assuming 15% selection intensity where two hybrids, viz., ZH161289 and ZH161303, were found to be common across all the moisture regimes, indicating their moisture stress resilience, a unique potential for broader adaptation in rainfed stress-vulnerable ecologies. The selected hybrids showed desired genetic gains such as positive gains for grainyield (almost 11% inoptimal anddrought; 22% in waterlogging) and negative gains in flowering traits. The view on strengths and weaknesses as depicted by the MGIDI assists the breeders to developmaize hybrids with desired traits, such as grain yield and other yield contributors under specific stress conditions. The MGIDI would be a robust and easy-to-handle multi-trait selection process under various test environments with minimal multicollinearity issues. It was found to be a powerful tool in developing better selection strategies and optimizing the breeding scheme, thus contributing to the development of climate-resilient maize hybrids. [ABSTRACT FROM AUTHOR]

Background: Potato (Solanum tuberosum L.) ranks fourth in terms of worldwide production. The states of Uttar Pradesh, West Bengal, Bihar and Gujarat accounted for more than 80 per cent share in total production; India ranks second, next to China in global production of potato. Potato crop is extremely sensitive to the deficit or surplus moisture and requires an optimum amount of irrigation at frequent intervals for its proper growth. Phosphorus (P) is an element that is potatoes require in large amounts following Nitrogen and Potassium, P application rates influence on the P efficiency for tuber yield and P uptake. Methods: In field study, total 36 treatment combinations consisting of three moisture regimes as main plot treatment and 12 combinations of two levels of FYM, three levels of P, carriers as sub-plot treatments evaluated in split plot design with three replications using potato variety Kufri pukhraj as test crop. Result: Among different moisture regimes tested, the treatment receiving maintenance of moisture between 100 and 75 per cent availability at 0-30 cm soil depth (W1) gave significantly higher plant height (52.24 cm), number of tubers per plant (6.74), total tuber yield (335.74 q/ha) and haulm yield (16.64 q/ha) during pooled results. Combinations of FYM and levels of P carriers tested, the treatment combinations FYM and application of P @ 180 kg P2O5/ha in the form of MAP(P3S1M1) showed significantly higher plant height (50.04 cm), tuber per plant (6.87), total tuber yield (323.98 q/ha) and haulm yield (17.16 q/ha) gave during pooled results. [ABSTRACT FROM AUTHOR]

An experiment was conducted to evaluate the effects of water deficit on physiobiochemical and yield parameters on sorghum during rabi season (September 2009 to February 2010) in Maharashtra. The treatment combinations consisted of four moisture regimes viz., M1, M2, M3 and M4 upto harvest and six genotypes viz., Phule Yashoda, RSV-1006, Phule Chitra, Phule Vasuda, Phule Anuradha, Phule Maulee. The study revealed that, Phule Yashoda and Phule Revati genotypes had maximum mean growth parameters and hence had maximum yield and yield contributing characters at lower moisture regime M1 than non-stress condition M4. RSV-1006 and Phule Chitra genotypes had maximum total soluble sugar content. The proline content increased with a decrease in the soil moisture content in all the genotypes with predominance in Phule Maulee, Phule Chitra and Phule Anuradha which also reported positive correlation of proline accumulation with grain yield. The degree of reduction in protein content as a function of water stress was less in Phlule Maulee, Phule Chitra and Phule Anuradha respectively. The genotypes Phlule Maulee, Phule Chitra and Phule Anuradha had lowest nitrate reductase activity under moisture regime M1. Among the six genotypes, Phule Yashoda and Phule Revati showed higher grain yield and yield contributing parameters. The present study revealed that genotypes Phule Chitra and Phule Maulee are more suited under limited soil moisture condition. Irrespective of moisture regime Phule Yashoda and RSV-1006 found better than rest of genotypes. Therefore, these genotypes are well suited for medium soil under stress as well as non-stress conditions. [ABSTRACT FROM AUTHOR]

This study was conducted with an objective of selecting the appropriate moisture regimes and to identify the key indicators of soil quality for different moisture regimes in NSLBC (LBC) of Nalgonda district of Andhra Pradesh. Soils are degrading due to several physical, chemical and biological constraints. Appropriate soil moisture regimes may help to check further soil degradation. This study was conducted in 2011 with six different soil moisture regimes of command and adjacent upland areas: command area- head reach, middle reach, tailend and upland area -- having assured irrigation, protective irrigation, rainfed. Sixty soil samples were collected from six different moisture regimes ten each from each moisture regime and were analyzed for physical, chemical and biological parameters. A standard methodology using principal component analysis (PCA) and linear scoring technique (LST) was adopted to identify the key indicators and for computation of soil quality indices. Among six moisture regimes, the soil quality index (SQI) ranged from 0.848 -- 0.945. The highest SQI was obtained in assured irrigation (0.945) followed by tail end (0.927) = protective irrigation (0.927), rainfed (0.897), head reach (0.889) while the lowest was under middle reach (0.848). The key indicators, which contributed considerably towards SQI, were bulk density, water holding capacity, organic carbon, dehydrogenase activity, available N, available Mn, ESP, available P, available K, pH and exchangeable Mg. [ABSTRACT FROM AUTHOR]

Persistence and leaching of thiamethoxam in soil were studied under laboratory conditions. The persistence studies carried out at two fortification levels and under three moisture regimes revealed that thiamethoxam persisted beyond 90 days in all the treatments with half-life varying from 46.3 to 301.0 days. Under dry conditions, the dissipation was faster at 10 mg kg−1 level as compared to 1 mg kg−1, whereas the reverse trend was observed under field capacity moisture and submerged conditions. The effect of moisture was prominent and longer persistence was observed under dry conditions (t1/2 200.7–301.0 days) followed by field capacity moisture (t1/2 91.2–94.1 days) and submerged condition (t1/2 46.3–75.3 days). The leaching experiment carried out under laboratory conditions showed that on leaching the soil column with water equivalent to 65 cm rainfall, 66–79% of the applied thiamethoxam was recovered from leachate and no residues were detected in soil. Results showed that thiamethoxam has a potential to leach down under heavy rainfall conditions. [ABSTRACT FROM AUTHOR]

Drought is a major constraint in drylands for crop production. Plant associated microbes can help plants in acquisition of soil nutrients to enhance productivity in stressful conditions. The current study was designed to illuminate the effectiveness of desert rhizobacterial strains on growth and net-return of chickpeas grown in pots by using sandy loam soil of Thal Pakistan desert. A total of 125 rhizobacterial strains were isolated, out of which 72 strains were inoculated with chickpeas in the growth chamber for 75 days to screen most efficient isolates. Amongst all, six bacterial strains (two rhizobia and four plant growth promoting rhizobacterial strains) significantly enhanced nodulation and shoot-root length as compared to other treatments. These promising strains were morphologically and biochemically characterized and identified through 16sRNA sequencing. Then, eight consortia of the identified isolates were formulated to evaluate the growth and development of chickpea at three moisture levels (55%, 75% and 95% of field capacity) in a glass house experiment. The trend for best performing consortia in terms of growth and development of chickpea remained T2 at moisture level 1 > T7 at moisture level 2 > T4 at moisture level 3. The present study indicates the vital role of co-inoculated bacterial strains in growth enhancement of chickpea under low moisture availability. It is concluded from the results that the consortium T2 (Mesorhizobium ciceri RZ-11 + Bacillus subtilis RP-01 + Bacillus mojavensis RS-14) can perform best in drought conditions (55% field capacity) and T4 (Mesorhizobium ciceri RZ-11 + Enterobacter Cloacae RP-08 + Providencia vermicola RS-15) can be adopted in irrigated areas (95% field capacity) for maximum productivity of chickpea. [ABSTRACT FROM AUTHOR]