Foliar Applied Moringa Leaf Extract Induces Terminal Heat Tolerance in Quinoa

摘要

Quinoa is a great value crop due to superior nutritional profile and abiotic stress tolerance however, its performance decreases under high temperature that can be improved by foliar application of moringa leaf extract (MLE) rich in antioxidants, growth promoters and minerals. This pot study focused to induce terminal heat tolerance in quinoa by foliar application of MLE. Foliar application of fresh MLE (MLEF), one month stored MLE (MLE1), two months stored MLE (MLE2), three months stored MLE (MLE3) and distilled water (control) were applied three times at fortnightly interval after start of high temperature treatment (76 days after sowing) on quinoa grown under ambient and heat stress conditions (±10?15oC of ambient). Quinoa growth drastically declined in heat stress conditions however, MLEF foliar application mitigated adverse effects of heat stress as indicated by more photosynthetic rate and intrinsic water use efficiency due to improved leaf chlorophyll and antioxidants found at flowering and grain filling stages. The efficacy of MLE declined with storage period. Nine percent (9%) increase in seed yield per plant under normal and 36% increase in heat stress conditions, with respective to their controls harvested from MLEF treated plants. Interestingly seed quality including protein and minerals contents did not affected by heat stress in this study.