Drought stress affects plant growth and development by altering physiological and biochemical processes resulting in reduced crop productivity. Zinc (Zn) is an essential micronutrient that plays fundamental roles in crop resistance against the drought stress by regulating various physiological and molecular mechanisms. Under drought stress, Zn application improves seed germination, plant water relations, cell membrane stability, osmolyte accumulation, stomatal regulation, water use efficiency and photosynthesis, thus resulting in significantly better plant performance. Moreover, Zn interacts with plant hormones, increases the expression of stress proteins and stimulates the antioxidant enzymes for counteracting drought effects. To better appraise the potential benefits arising from optimum Zn nutrition, in the present review we discuss the role of Zn in plants under drought stress. Our aim is to provide a complete, updated picture in order to orientate future research directions on this topic.

The concentration of greenhouse gases (GHGs) in the atmosphere has been increasing since the beginning of the industrial revolution. Nitrous oxide (N₂O) is one of the mightiest GHGs, and agriculture is one of the main sources of N₂O emissions. In this paper, we reviewed the mechanisms triggering N₂O emissions and the role of agricultural practices in their mitigation. The amount of N₂O produced from the soil through the combined processes of nitrification and denitrification is profoundly influenced by temperature, moisture, carbon, nitrogen and oxygen contents. These factors can be manipulated to a significant extent through field management practices, influencing N₂O emission. The relationships between N₂O occurrence and factors regulating it are an important premise for devising mitigation strategies. Here, we evaluated various options in the literature and found that N₂O emissions can be effectively reduced by intervening on time and through the method of N supply (30–40%, with peaks up to 80%), tillage and irrigation practices (both in non-univocal way), use of amendments, such as biochar and lime (up to 80%), use of slow-release fertilizers and/or nitrification inhibitors (up to 50%), plant treatment with arbuscular mycorrhizal fungi (up to 75%), appropriate crop rotations and schemes (up to 50%), and integrated nutrient management (in a non-univocal way). In conclusion, acting on N supply (fertilizer type, dose, time, method, etc.) is the most straightforward way to achieve significant N₂O reductions without compromising crop yields. However, tuning the rest of crop management (tillage, irrigation, rotation, etc.) to principles of good agricultural practices is also advisable, as it can fetch significant N₂O abatement vs. the risk of unexpected rise, which can be incurred by unwary management.

Genome editing (GE) has revolutionized the biological sciences by creating a novel approach for manipulating the genomes of living organisms. Many tools have been developed in recent years to enable the editing of complex genomes. Therefore, a reliable and rapid approach for increasing yield and tolerance to various environmental stresses is necessary to sustain agricultural crop production for global food security. This critical review elaborates the GE tools used for crop improvement. These tools include mega-nucleases (MNs), such as zinc-finger nucleases (ZFNs), and transcriptional activator-like effector nucleases (TALENs), and clustered regularly interspaced short palindromic repeats (CRISPR). Specifically, this review addresses the latest advancements in the role of CRISPR/Cas9 for genome manipulation for major crop improvement, including yield and quality development of biotic stress- and abiotic stress-tolerant crops. Implementation of this technique will lead to the production of non-transgene crops with preferred characteristics that can result in enhanced yield capacity under various environmental stresses. The CRISPR/Cas9 technique can be combined with current and potential breeding methods (e.g., speed breeding and omics-assisted breeding) to enhance agricultural productivity to ensure food security. We have also discussed the challenges and limitations of CRISPR/Cas9. This information will be useful to plant breeders and researchers in the thorough investigation of the use of CRISPR/Cas9 to boost crops by targeting the gene of interest.

Abiotic stresses are one of the significant threats to soybean (Glycine max L.) growth and yields worldwide. Soybean has a crucial role in the global food supply chain and food security and contributes the main protein share compared to other crops. Hence, there is a vast scientific saddle on soybean researchers to develop tolerant genotypes to meet the growing need of food for the huge population. A large portion of cultivated land is damaged by salinity stress, and the situation worsens yearly. In past years, many attempts have increased soybean resilience to salinity stress. Different molecular techniques such as quantitative trait loci mapping (QTL), genetic engineering, transcriptome, transcription factor analysis (TFs), CRISPR/Cas9, as well as other conventional methods are used for the breeding of salt-tolerant cultivars of soybean to safeguard its yield under changing environments. These powerful genetic tools ensure sustainable soybean yields, preserving genetic variability for future use. Only a few reports about a detailed overview of soybean salinity tolerance have been published. Therefore, this review focuses on a detailed overview of several molecular techniques for soybean salinity tolerance and draws a future research direction. Thus, the updated review will provide complete guidelines for researchers working on the genetic mechanism of salinity tolerance in soybean.

Industrial pollution has been continuously soaring and causing serious threats to the soil, water, and air quality. The increase in industrialization has not only covered the large areas, but also created a large quantity of wastewater which is difficult to handle. The water produced from different industries is getting its place in the agriculture. However, the challenge is to properly use wastewater, so that the application of wastewater does not cause any soil and environmental problems. The distillery spent wash (DSW) is a liquid waste that is produced from the sugarcane industry. It contains a large load of both organic and inorganic substances. Also, DSW contains a sufficient amount of macronutrients (nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and Sulphur (S)) and micronutrients (zinc (Zn), copper (Cu), iron (Fe) and manganese (Mn)), which in turn improves the growth and yield of crops. The optimized doses of DSW substantially improve soil enzymatic and microbial activities, organic carbon, nutrient uptake, soil porosity, water holding capacity, aggregate stability, and anti-oxidant activities, which in turn improve the photosynthetic efficiency, growth and yield. However, the inadequate knowledge about the DSW characteristics and methods of its agricultural application present questions concerning environmental quality for groundwater pollution. Therefore, to obtain a better understanding about the DWS, here, we discussed the effects of DSW on soil quality, crop yield, and its implications for agriculture and water quality.

As a most significant cereal crop, maize provides vital nutritional components to humans and livestock. Drought stress curtails maize growth and yield by impairing several morphological, physiological, and biochemical functions. The rising threats of drought stress significantly affect global food security and increase the ratio of hunger and starvation. The use of molecular breeding techniques has enabled maize researchers to deeply examine the genetic control of drought tolerance and the genetic differences between genotypes to drought stress. Despite the significant progress in molecular genetics, the drought tolerance mechanism is still not fully understood. With the advancements in molecular research, researchers have identified several molecular factors associated with maize tolerance to drought stress. Quantitative trait loci (QTL) mapping and genome-wide association study (GWAS) analysis have led to identifying QTL, and genes linked to drought tolerance in maize that can be further exploited for their possible breeding applications. Transcriptome and transcription factors (TFs) analysis has revealed the documentation of potential genes and protein groups that might be linked to drought tolerance and accelerate the drought breeding program. Genetic engineering has been used to develop transgenic maize cultivars that are resistant to drought stress. Clustered regularly interspaced short palindromic repeats (CRISPR/Cas9) is a new ray of hope to edit the gene of interest to enhance drought tolerance in maize and save both time and cost in cultivar development. In the current review article, we have tried to present an updated picture of the advancements of drought tolerance in maize and its future prospects. These organized pieces of information can assist future researchers in understanding the basis of drought tolerance to adopt a potential breeding tool for breeding drought-tolerant maize cultivars.