ANALYSIS OF DROUGHT RESILIENCE, GROWTH AND RECOVERY IN TOMATO SEEDLINGS WITH PGPR-BIO-PRIMING

Abstract

The present study was conducted on a highly commercialized crop plant- tomato, a rich source of vitamin A, C and E, as well as minerals. Several antioxidants and phenolic compounds are also present. Tomato is cultivated worldwide for its high nutritional value. Undenied fact is that healthy seedlings ensure the healthy yields so it is necessary to understand the possible threats of scarcity of water to seedling growth. As we know mature plant have several stress management strategies so it is interesting to find the effect of stress at seedling stage. Healthy seeds of tomato were surface-sterilized then subjected to inoculation with plant growth-promoting rhizobacteria (PGPR). A mixture of Azotobacter and Bacillus polymyxa (1:1) was used as PGPR. Inoculated and non-inoculated seeds were grown and the seedlings were subsequently exposed to water stress for 2, 3 and 5 days respectively. Various biochemical tests were conducted in order to determine the impact of mild and severe water stress on inoculated and non-inoculated plants. We found that plants which are inoculated with PGPR exhibited a lower impact of water stress and showed a higher recovery rate in comparison to non-inoculated plants. However, mild stress had no significant impact on plant health, and plants recovered better when rewatered. Severe stress had negative effect on photosynthetic pigments and protein content while proline and carotenoids were increased. Inoculated seedlings exhibited lower MDA content, indicating reduced lipid peroxidation. This study highlights the beneficial effects of PGPR in improving drought tolerance and recovery in tomato seedlings. The findings support the use of PGPR as an eco-friendly strategy to enhance crop productivity under water-deficit conditions, offering a sustainable approach to agricultural management in stress-prone environments.