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Energy budgeting is important for determining the sustainability and vulnerability of a crop production system. In the present study, an assessment of the energy requirements for cashew cultivation under three different planting densities was carried out during 2015-20. The study revealed that the total input energy consumption for cashew cultivation ranged from 75292.68 to 120903.58 MJ/ha. The energy productivity from 0.04 to 0.13 kg/MJ and energy use efficiency varied from 8.46 to 24.61% under three planting densities. The highest energy was consumed in terms of chemical fertilizers for all the planting densities followed by fuel (diesel), machinery, farmyard manure (FYM), pesticides, petrol and human energy. The analysis revealed the need to implement improved management practices to enhance the energy efficiency by reducing the energy consumption in inputs, by optimizing energy consumption and/or improving the crop yield by optimizing the cultivation methods and switching from non-renewable sources to renewable sources of energy. Among the three different planting densities, 2.5x2.5 m spacing consumed the highest energy followed by 5x5 m and 7.5x7.5m spacing. However, the planting density of 2.5x2.5 m spacing was more energy efficient over the years due to more yields per unit area.

The development of salinity affects 7% of the world’s land surface, acting as a major constraint to crop productivity. This study attempted to use the co-evolving endophytes of peanut to alleviate salinity stress and enhance the yield of peanut. Diverse and different tissue colonizing endophytes were isolated from peanut and screened in vitro by seed germination bioassay imposing gradients of salinity, with two cultivars TG37A (susceptible) and GG2 (moderately resistant), in potted conditions using saline irrigation water. Finally, nine endophytes capable of producing IAA and ACC-deaminase, promoting root growth and yield in potted conditions were selected for further evaluation in field conditions. They were evaluated with saline water (1.5–2.0 dS/m) in saline soil with susceptible cultivar TG37A. Simultaneously, three endophytes (Bacillus firmus J22N; Bacillus tequilensis SEN15N; and Bacillus sp. REN51N) were evaluated with two cultivars, GG2 and TG37A, during rainy and post-rainy seasons with elevated salinity. The application of endophytes like Bacillus firmus J22N and Bacillus sp. REN51N enhanced the pod and haulm yield of peanuts by 14–19% across cultivars, salinity, and seasons. In addition, there was significant modulation in parameters like relative water content; production of enzymes like superoxide dismutase (SOD), glutathione reductase (GR), catalase (CAT), ascorbate peroxidase (APX), lipid peroxidase (POD), and H2O2 content in leaf; and uptake of potassium. The activities of the enzymes involved in scavenging reactive oxygen species (ROS) increased with salinity, and further increased with endophytes like Bacillus firmus J22N, Bacillus tequilensis SEN15N, and Bacillus sp. REN51N. There was an enhanced accumulation of proline, reduced level of phenol and H2O2, and enhanced uptake of potassium with the inoculation of endophytes. This improved scavenging capacity of plants by endophytic modulation of ROS scavengers, uptake of K, production of ACC deaminase and IAA, root and biomass growth, modulation in relative water content, and enhanced accumulation of osmoprotectant might be the reasons of alleviation of salinity stress. Endophytes could have alleviated salinity stress in peanuts, indicating the mechanisms and potential of peanuts at the field level. These endophytes could be applied to bring agricultural sustainability to salinity-affected areas in the future. Furthermore, few genera viz. Kocuria, Brevundimonas, Agrococcus, Dietzia, and Kytococcus were observed in peanut tissue for the first time.

An experiment was conducted in micro-plots filled with sandy loam soil having 14% clay and 0.33% organic carbon to see the responses of halophytic grasses Sporobolus marginatus and Urochondra setulosa collected from the extreme saline-sodic Kachchh plains, Bhuj, Gujarat, India under alkalinity/salinity. Maximum photosynthetic rate was recorded in control treatment. Photosynthetic rate decreased at pH 9.0 + EC 20 dS/m (11.25 and 17.8 μmol CO2/m2/s) in S. marginatus and U. setulosa respectively, along with reduction in stomatal conductance and transpiration rate. In comparison to control, increased accumulation of total soluble sugars and proline may be due to increased osmotic adjustment for both halophytes. Similarly, at mixed stress of pH 9.0 with EC 20 dS/m, the epicuticular wax load increased in both S. marginatus and U. setulosa (24.0 and 40.0 mg/g). A positive correlation of stress was seen with Na+ and Cl‑ content while negative correlation with K+ content. Na+ content increased to about 3-7 fold at salinity level, EC 35 dS/m. Similarly, with treatment of mixed stress of pH 9.0 with saline level EC 20dS/m, 3-6 times increase in Na+ with decrease in K+ was observed in S. marginatus and U. setulosa respectively. These grass species maintained better gas exchange properties with higher osmolytes accumulations and balanced ionic relations under high stress conditions of salinity and alkalinity. These attributes might be providing physiological adaptable mechanisms for growth under salt affected environments.