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Wheat constitutes pivotal position for ensuring food and nutritional security; however, rapidly rising soil and water salinity pose a serious threat to its production globally. Salinity stress negatively affects the growth and development of wheat leading to diminished grain yield and quality. Wheat plants utilize a range of physiological biochemical and molecular mechanisms to adapt under salinity stress at the cell, tissue as well as whole plant levels to optimize the growth, and yield by off-setting the adverse effects of saline environment. Recently, various adaptation and management strategies have been developed to reduce the deleterious effects of salinity stress to maximize the production and nutritional quality of wheat. This review emphasizes and synthesizes the deleterious effects of salinity stress on wheat yield and quality along with highlighting the adaptation and mitigation strategies for sustainable wheat production to ensure food security of skyrocketing population under changing climate.

Plant growth regulators are naturally biosynthesized chemicals in plants that influence physiological processes. Their synthetic analogous trigger numerous biochemical and physiological processes involved in the growth and development of plants. Nowadays, due to changing climatic scenario, numerous biotic and abiotic stresses hamper seed germination, seedling growth, and plant development leading to a decline in biological and economic yields. However, plant growth regulators (PGRs) can potentially play a fundamental role in regulating plant responses to various abiotic stresses and hence, contribute to plant adaptation under adverse environments. The major effects of abiotic stresses are growth and yield disturbance, and both these effects are directly overseen by the PGRs. Different types of PGRs such as abscisic acid (ABA), salicylic acid (SA), ethylene (ET), and jasmonates (JAs) are connected to boosting the response of plants to multiple stresses. In contrast, PGRs including cytokinins (CKs), gibberellins (GAs), auxin, and relatively novel PGRs such as strigolactones (SLs), and brassinosteroids (BRs) are involved in plant growth and development under normal and stressful environmental conditions. Besides, polyamines and nitric oxide (NO), although not considered as phytohormones, have been included in the current review due to their involvement in the regulation of several plant processes and stress responses. These PGRs are crucial for regulating stress adaptation through the modulates physiological, biochemical, and molecular processes and activation of the defense system, upregulating of transcript levels, transcription factors, metabolism genes, and stress proteins at cellular levels. The current review presents an acumen of the recent progress made on different PGRs to improve plant tolerance to abiotic stress such as heat, drought, salinity, and flood. Moreover, it highlights the research gaps on underlying mechanisms of PGRs biosynthesis under stressed conditions and their potential roles in imparting tolerance against adverse effects of suboptimal growth conditions.

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The rapidly increasing human population is an alarming issue and would need more food production under changing climate. Abiotic stresses like heat stress and temperature fluctuation are becoming key issues to be addressed for boosting crop production. Maize growth and productivity are sensitive to temperature fluctuations. Grain yield losses in maize from heat stress are expected to increase owing to higher temperatures during the growing season. This situation demands the development of maize hybrids tolerant to heat and drought stresses without compromising grain yield under stress conditions. The chapter aimed to assess the updates on the influence of high-temperature stress (HTS) on the physio-biochemical processes in plants and to draw an association between yield components and heat stress on maize. Moreover, exogenous applications of protectants, antioxidants, and signaling molecules induce HTS tolerance in maize plants and could help the plants cope with HTS by scavenging reactive oxygen species, upregulation of antioxidant enzymes, and protection of cellular membranes by the accrual of compatible osmolytes. It is expected that a better thought of the physiological basis of HTS tolerance in maize plants will help to develop HTS maize cultivars. Developing HTS-tolerant maize varieties may ensure crops production sustainability along with promoting food and feed security under changing climate.

Peanut (Arachis hypogaea L.) is adorned as the one of the important sources of vegetable oil, protein, vitamins and several minerals, which could mitigate the nutritional gap worldwide. However, peanut cultivation in winter suffers from low temperature stress and knowledge lacuna regarding the optimum dose nitrogen. Therefore, the present investigations were carried out during the winter seasons 2015–2016 and 2016–2017 at the district seed farm of Bidhan Chandra Krishi Viswavidyalaya, an agricultural university in West Bengal, India (23°26’ N, 88°22´ E, elevation 12 m above mean sea level) to facilitate the comprehensive study of plant growth, productivity and profitability of an irrigated peanut crop under varied levels of nitrogen: with and without a rhizobium inoculants and with and without polythene mulch. Quality traits and nutrient dynamics were also itemized. Fertilizing with 100% of the recommended dose of nitrogen combined with rhizobium inoculant and polythene mulch significantly enhanced peanut plant growth, yield and yield-attributing traits, while resulting in the maximum fertilizer (i.e., nitrogen, phosphorus and potassium) uptake by different plant parts. The greatest number of root nodules occurred in the treatment that received 75% of the recommended dose of nitrogen with rhizobium supplementation under polythene mulch, while 50% of the recommended dose of nitrogen with no rhizobium resulted in maximum fertilizer nitrogen use efficiency. Applying the full recommended dose of nitrogen with the rhizobium inoculants and mulch resulted in maximum profitability in the peanut crop.

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This study evaluated the role of gibberellic acid [GA3; (0, 100, 200, and 300 ppm)] in modulation of the growth, physiology, yield, and quality traits in two varieties (BARI Mung-6 and BARI Mung-8) of mungbean (Vigna radiata L.). Irrespective of the two varieties (BARI Mung-6 and BARI Mung-8), 100, 200, and 300 ppm of GA3 differentially modulated the tested parameters (relative water content, RWC; photosynthetic pigments: chlorophyll a, chlorophyll b, and carotenoids; growth parameters: fresh and dry weights of leaves, petioles, stems, and roots; yield contributing traits such as plant height, number of pods plant−1, number of grains pod−1, pod length, and 100-grain weight; quality traits such as grain nitrogen and protein). However, compared to the lowest GA3 (100 ppm) and the highest GA3 (300 ppm), the moderate concentration of GA3 (200 ppm) led to highest values of leaf-RWC, where this parameter exhibited 16.1 and 13.4% increase in BARI Mung-8 and BARI Mung-6, respectively. Similarly, the tested herein growth parameters and the yield traits significantly increased up to the foliar application of the moderate GA3 concentration (200 ppm), and thereafter these traits decreased with 300 ppm GA3. The 200 ppm-led changes in the growth and yield traits were significantly higher in BARI Mung-8 when compared to BARI Mung-6. Considering the quality traits, GA3 positively influenced the nitrogen and protein content in grains, where 200 ppm of GA3 led to increases of 25.2% in N, and 17.7% in protein over control in BARI Mung-6; whereas, BARI Mung-8 exhibited 28.3% in N, and 18.3% in protein with 200 ppm GA3 over control. Overall, BARI Mung-8 significantly responded to the foliar supply of 200 ppm GA3 when compared to BARI Mung-6. Hence, in order to high yield and grain protein content, the application of 200 ppm GA3 may be applied in V. radiata before and during flowering. The major mechanisms underlying the responses of the water relation, growth, and yield traits to the GA3 concentrations need to be explored.