Water scarceness is a major threat to wheat productivity under changing climate scenarios, especially in arid and semi-arid regions. However, growing drought-tolerant wheat genotypes could be a sustainable option to enhance wheat productivity under drought stress conditions. The aim of this study was to evaluate the effect of mild to severe drought stress on gas exchange parameters, relative water content, SPAD-chlorophyll value, and yield-related parameters of 14 wheat genotypes being cultivated in arid to semi-arid areas on large scale. The genotypes were grown in earthen pots under three drought levels, namely (1) control-well watered, (2) mild water stress, i.e., 60% water holding capacity, and (3) severe water stress, i.e., 40% water holding capacity. The drought was imposed from the jointing stage to physiological maturity. Drought significantly decreased net photosynthesis, stomatal conductance, relative water contents, 100-grain weight, and grain yield in all genotypes. However, the reduction percentage was different in different genotypes under drought stress compared with well-watered conditions. The highest relative water content (65.2%) was maintained by the genotype Galaxy-2013, followed by AAS-2011 (64.6%) and Johar-2016 (62.3%) under severe drought conditions. Likewise, Galaxy-2013 showed the highest net photosynthesis and stomatal conductance under severe drought conditions. The highest grain yield per plant (6.2 g) and 100-grain weight (3.3 g) was also recorded in Galaxy-2013 under severe drought conditions, while the highest grain yield under well-watered conditions was recorded in Johar-2016, followed by Galaxy-2013. These results suggest that wheat variety Galaxy-2013 could be cultivated extensively to obtain good wheat yield under limited water conditions.

Soil salinity disrupts the physiological and biochemical processes of crop plants and ultimately leads to compromising future food security. Sodium nitroprusside (SNP), a contributor to nitric oxide (NO), holds the potential to alleviate abiotic stress effects and boost tolerance in plants, whereas less information is available on its role in salt-stressed lentils. We examined the effect of exogenously applied SNP on salt-stressed lentil plants by monitoring plant growth and yield-related attributes, biochemistry of enzymes (superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD)) amassing of leaf malondialdehyde (MDA) and hydrogen peroxide (H₂O₂). Salinity stress was induced by NaCl application at concentrations of 50 mM (moderate salinity) and 100 mM (severe salinity), while it was alleviated by SNP application at concentrations of 50 µM and 100 µM. Salinity stress severely inhibited the length of roots and shoots, the relative water content, and the chlorophyll content of the leaves, the number of branches, pods, seeds, seed yield, and biomass per plant. In addition, MDA, H₂O₂ as well as SOD, CAT, and POD activities were increased with increasing salinity levels. Plants supplemented with SNP (100 µM) showed a significant improvement in the growth- and yield-contributing parameters, especially in plants grown under moderate salinity (50 mM NaCl). Essentially, the application of 100 µM SNP remained effective to rescue lentil plants under moderate salinity by regulating plant growth and biochemical pathways. Thus, the exogenous application of SNP could be developed as a useful strategy for improving the performance of lentil plants in salinity-prone environments.

Changing climates and frequent spells of drought have increased the risk of crop failure, especially in arid and semi-arid regions, thus multiplying the vulnerability of food-insecure populations. The exogenous application of potassium (K) can potentially ameliorate the adverse effects of drought in maize by maintaining cell osmotic potential and turgidity, provided its optimum doses are applied. The present experiment comprised two maize cultivars, viz. Islamabad Gold (drought tolerant) and Azam (drought susceptible), grown under well-watered (80% water-holding capacity (WHC)), mild drought (60% WHC) and severe drought (40% WHC) conditions. Different doses of K, viz. 0%, 1% and 2%, were also tested to screen out the most superior concentration. Drought stress markedly reduced root and shoot lengths (25% and 16%, respectively) along with their dry weights (20% and 10%, respectively). Moreover, a substantial reduction in leaf relative water content (RWC) (24%), stomatal conductance, transpiration and photosynthesis rates, chlorophyll pigments a, b and total chlorophyll contents (31%) were recorded, compared with well-watered conditions. However, foliar application of K₂SO₄ at 2% concentration outperformed other doses by improving growth attributes, RWC (10%), total chlorophyll (9%) and proline (12%) under severe drought conditions. Our findings confirmed the effectiveness of foliage-applied K₂SO₄ in ameliorating drought effects in rainfed maize; however, more doses and sources of K could be tested for developing it as a potent source to cope with water stress.

Livestock development in rainfed areas is slower due to the inadequate supply of nutritious fodder. Mono-cropping systems also have a negative impact on forage yield and nutrition as cereals are deficient in protein. Hence, there is a dire need to grow cereals with legumes to improve forage yield and quality. Therefore, a two-year field study was undertaken to evaluate winter cereal–legume forage and their mixtures viz. oats (cv. PD₂-LV₆₅), barley (Jau-86) and one legume viz. vetch (cv. Languedock) under different tillage systems viz. conventional tillage (moldboard plow+4-cultivation with tines) and conservation tillage (3-cultivation with tines). Crops were grown in pure stands as well as in mixtures with a 70:30 seeding ratio. The results revealed that the conventional tillage system performed better in terms of numbers of tillers/branches, leaf-to-stem ratio and green fodder yield than the conservation tillage system. However, the conventional and conservation tillage systems did not show a significant difference in terms of crude protein, acid detergent fiber and neutral detergent fiber. In the pure stands and cereal–legume mixtures, the oat–vetch mixture performed better in terms of plant height, leaf-to-stem ratio and green fodder yield. The maximum crude protein content was observed in the oat–vetch mixture, while the maximum acid detergent fiber and neutral detergent fiber were observed in the pure oat stands. In competitive indices, the land-equivalent ratio and competitive ratio showed the advantage of intercropping. In actual yield loss, results showed the positive value of barley and oats in mixtures, which reflects the advantage of intercropping in the rainfed areas. The economic analysis showed a greater net benefit from the conventional tillage than the conservation tillage system under rainfed conditions. On the basis of this investigation, an oat–vetch mixture and the conventional tillage system are recommended for higher tonnage of nutritious fodder in rainfed areas.