Investigating the combined effects of PGPR inoculants and biochar on physiochemical responses of ground nut (Arachis hypogaea L.) under drought stress

Abstract

Peanut is one of the major economical legume and oilseed crop in Pakistan. It is of widely used in crop rotation and intercropping systems due to its ability to develop symbiotic association with soil bacteria for BNF. However, the impact of drought on disease, nutrition, and yield loss poses significant challenges for the peanut industry. With the world's population on the rise, water scarcity is becoming an increasing concern for agricultural activities. Exploring novel drought control methods is essential to sustain peanut production. This study explores the significant effect of use of cotton straw biochar and PGPR (Plant Growth-Promoting Rhizobacteria)-based biofertilizers as a potential remedy for drought tolerance. The experiment was conducted using a randomized complete block design in a greenhouse setting, evaluating the performance of two variable ratios of biochar in combination with PGPRs in peanut. The primary objectives were to assess whether cotton straw biochar and PGPR-based biofertilizer could improve drought tolerance in peanuts while maintaining normal growth pattern. The results of this study showed that the combination of cotton straw biochar and PGPR-based biofertilizer significantly enhanced drought tolerance in peanuts. Morphological traits were observed to be significantly enhanced in the presence of Biochar and PGPR application under drought stress. Biochemical profile of plants treated with biochar also showed lower levels of ROS accumulation in leaf tissues when drought was induced. Metabolic profile of root exudates showed significant changes in signaling molecules involved in nodulation and BNF process. To further exploit the potential benefits of this approach, future research should focus on molecular mechanisms involved in modulating nodulation process in peanut under drought stress for enhancement of plant growth as well as soil nutrient.