Soil moisture and air temperature stress are the two major abiotic factors limiting lentil (Lens culinaris Medik.) growth and productivity in the humid tropics. Field experiments were conducted during winter seasons (November to March) of 2018–2019 and 2019–2020 on clay loam soil (AericHaplaquept) of Eastern India to cultivate rainfed lentil, with residual moisture. The objective was to study the effect of different time of sowing and foliar spray of micronutrients in ameliorating the effect of heat and moisture stress lentil crop experience in its reproductive stage. The study was conducted with two different dates of sowing, November and December, as main plot treatment and micronutrients foliar spray of boron, iron, and zinc either alone or in combination as subplot treatment. No foliar spray treatment was considered as a control. The soil moisture content is depleted from 38 to 18% (sowing to harvest) during November sowing; however, in December sowing, the depletion is from 30 to 15%. The foliar spray of micronutrients helped to have a better canopy cover and thus reduced soil evaporation during the later stages of crop growth when the temperature was beyond the threshold temperature of the crop. Crop growth rate (CGR) and biomass were significantly higher (p ≤ 0.05) for November sown crop and with foliar spray of boron and iron (FSB + FE) micronutrients. In the later stages of the crop when the soil moisture started depleting with no precipitation, the canopy temperature increased compared with air temperature, leading to positive values of Stress Degree Days (SDD) index. Delay in sowing reduced the duration by 11.4 days (113.5 vs. 102.1 days), resulting in varied accumulated Growing Degree Days (GDD). FSB + FE resulted in the highest yield in both years (1,436 and 1,439 kg ha−1). The results of the study concluded that the optimum time of sowing and foliar spray of micronutrients may be helpful to alleviate the soil moisture and heat stress for the sustainability of lentil production in the subtropical region.

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Drought stress is one of the limiting factors for grain filling and yield in wheat. The grain filling and determinants of individual grain weight depend on current assimilation and extent of remobilization of culm reserves to grains. A pot experiment was conducted with eight wheat cultivars at the Pot House to study the grain filling and the contributions of reserves in culm, including the sheath to grain yield under drought stress. Drought stress was enforced by restricting irrigation during the grain-filling period. The plants (tillers) were harvested at anthesis, milk-ripe, and maturity. The changes in dry weights of leaves, culm with sheath, spikes, and grains; and the contribution of culm reserves to grain yield were determined. Results revealed that drought stress considerably decreased the grain filling duration by 15–24% and grain yield by 11–34%. Further, drought-induced early leaf senescence and reduced total dry matter production indicate the minimum contribution of current assimilation to grain yield. The stress reduced the contribution of culm reserves, the water-soluble carbohydrates (WSCs), to the grains. The accumulation of culm WSCs reached peak at milk ripe stage in control, varied from 28.6 to 84 mg culm−1 and that significantly reduced in the range from 14.9 to 40.6 mg culm−1 in stressed plants. The residual culm WSCs in control and stressed plants varied from 1.23 to 8.12 and 1.00 to 3.40 mg g−1 culm dry mass, respectively. BARI Gom 24 exhibited a higher contribution of culm WSCs to grain yield under drought, while the lowest contribution was found in Kanchan. Considering culm reserves WSCs and their remobilization along with other studied traits, BARI Gom 24 showed greater drought tolerance and revealed potential to grow under water deficit conditions in comparison to other cultivars.

Medium-term storage for some medicinal plant species collected from Taif governorate was developed. First, the establishment of in vitro propagation system for Caper (Capparis spinosa L) and Lavender (Lavandula dentata L.) plants was studied using axillary buds as explants. Murashige and Skoag (MS) salts with different concentrations and combinations of auxins and cytokinens were used. Second, Shoot tips and nodal buds from in vitro culture plants (C. spinosa L, L. dentata L and Rhazya stricta Decne) were used as explants for in vitro conservation experiments. Eighteen different treatments were used as slow growth medium. After 12 months from conservation, in R. stricta Decne and C. spinosa L a highest percentage of survival rates (91.1% and 93.33%), respectively, were observed on MS + 10 g/L sucrose + 10 g/L sorbitol. However, in L. dentata L the highest percentage of survival rate (90%) was noted on MS + 15 g/L sucrose +10 g/L sorbitol. Random amplified polymorphic DNA (RAPD) analysis indicated high genetic stability of preserved plant species under investigation. These results suggested that, in vitro conservation using full strength MS salts with low concentrations of sucrose and sorbitol as a carbon source and osmotic agent, respectively, is a suitable slow growth medium for in vitro conservation of C. spinosa L, L. dentata and R. stricta Decne plants.

Nitrogen management is vital for economic and environmental sustainability. Asynchrony of fertilizer application with crop demand along various nitrogen losses in Eastern India leads to low fertilizer efficiency in Kharif rice. At the same time, direct-sowing is gaining popularity due to water and labor scarcity. In an experiment between 2017–2018 in West Bengal, India, the main plots represented establishment methods: conventional transplanting, TPR; direct-seeded rice, DSR; and drum seeded rice, DRR; while subplots represented nitrogen management options: farmer’s practice (FP), the state-recommended (SR), nutrient expert-based (NE), Green seeker-based (GS) and LCC-based (LCC) in a split-plot design with three repetitions. Plant growth, productivity, and profitability were evaluated. All indicators of growth or production were affected by establishment methods and by N-management options. The yield enhancement of TPR and DSR over DRR was 21.1 and 16.8%, respectively, while it was enhanced by 19.21, 14.71, 6.49, and 2.52% by GS, NE, LCC, and SR, respectively, over FP. The highest net return and return per rupee invested were recorded with DSR, while both GS and NE had better economics. The results suggest that the combination of DSR establishment with GS or NE requires further studies to find climate-smart management techniques in Kharif rice.

Calcareous soils are highly deficient in boron (B) due to having high levels of free CaCO3 and low organic matter. This has become one of the most important deficient micronutrients in Indian soil after zinc (Zn). For various rice (Oryza sativa L.)-based cropping systems, B fertilization is essential for increasing crop productivity and the biofortification of the crop, thus a suitable soil application protocol for B fertilization is required for B-deficient soils. In a six-year experiment, different rates of B application, namely, 0.5, 1.0, 1.5, and 2.0 kg ha−1 y−1, were evaluated to determine the effects of three different modes of B fertilization, i.e., applied only in the first year, applied in alternating years, and applied every year, in a rice (Oryza sativa L.)–Indian mustard (Brassica juncea L.) cropping system. It was observed that the application of B at 1.5 kg ha−1 every year or 2 kg ha−1 in alternate years resulted in the highest yield of rice and mustard, as well as the maximum system productivity of the rice–mustard cropping system. Application of 2 kg ha−1 of B in the initial year showed the maximum B uptake by rice, while application of 1.5–2.0 kg ha−1 of B every year resulted in the maximum B uptake by the mustard crop. Application of B at 2 kg ha−1 in alternate years or 1.5 kg ha−1 every year was the best B-application protocol in B-deficient calcareous soils for ensuring the highest productivity of the rice–mustard cropping system and B availability in the soil.

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