Effect of partial rhizosphere drying on plant photosynthetic, antioxidative and water related indicators in cotton

Abstract

ABSTRACT Freshwater resources are severely declining due to climate change. However, the use of water saving strategies is a prime objective of this century. Many techniques have been developed to cope this core issue. Among them, Partial rhizosphere drying (PRD) being one of the effective approaches plays a major role to reduce the harmful effects of water deficit stress. In PRD, the rhizosphere is divided in two equal halves, each portion irrigated in alternate scheduling to save 50% water. This study was designed to evaluate the performance of five cotton varieties (FH-142, IUB-222, IUB-13, MM-58 and NOOR) under full irrigation (FI) and drought (partial root zone drying, PRD). Results revealed that MM-58 performed the best among other varieties, particularly through improved rate of stomata conductance (32.17%), photosynthesis (24.24%), water-related parameters (16.69%, 36.88% and 43.34% for LRWC, LOP and LTP respectively) and antioxidants activity (19.86%, 43.90%, 20.51% and 21.11% for SOD, POD, CAT and APX respectively) compared to NOOR. Moreover, higher values of growth (PH, LAI) and water related parameters were found in FI while osmolyte accumulation (Sugar and Proline) and antioxidants (SOD, POD, CAT, APX) were more in PRD. In crux, the above traits are the best indicators to screen out any crop varieties especially cotton at the early developmental stage to save time in breeding programs.