Exploring the effect of Jasmonic Acid for Aphids control for improving the yield of Triticum aestivum varieties

Abstract

Many biotic and abiotic factors influence the production of wheat (Triticum aestivum L.). Among biological agents, aphids are destructive pests effecting wheat yield drastically. This study was designed to evaluate the impact of foliar Jasmonic acid spray on aphid population as well as on plant growth during aphid infestation in two wheat varieties i.e., Borlaug-2015 and Zincol-2015. Plants are cultivated in pots and treated with jasmonic acid at concentrations of 0.1 and 1 mM (JA). The results revealed that length of shoot and roots decreased after aphid stress and was improved (21-24%) by JA spray. Photosynthetic pigments increased after applying the jasmonic acid spray compared to control plants. Jasmonic acid spray helped the plants to recover from aphid stress by enhanced production of antioxidant enzymes CAT (Catalase) (65-71%), SOD (Superoxide dismutase) (71-74%) and POD (Peroxidase) (61-65%). Consequent to improved defence system, plants treated with JA had fewer aphids as compared to control (60-73% reduction), 24 h after spray. The higher concentration of JA (1 mM) proved more effective as compared to 0.1 mM jasmonic acid. Moreover, Zincol-2015 appeared tolerant as compared to Borlaug-2015 against aphid infestation. The application of jasmonic acid as an exogenous foliar application showed an overall positive impact on the physiological and biochemical attributes of both varieties. It helps the plants to enhance resistance against the biotic stress and can be adopted as future alternative for aphid management. However, detailed studies regarding understanding of underlying molecular mechanisms are needed to optimize the mode for field application.

Keywords: Antioxidants; Aphids; Control; Jasmonic acid; Wheat.

Figure 1. Effect of foliar application of jasmonic acid with and without aphid stress, on plant height (cm) (A), plant root length (cm) (B), shoot fresh weight (g) (C), root fresh weight (g) (D), and Leaf relative water content (E), of two varieties of wheat i.e., Borlaug-20.

Values are per gram fresh weight of sample. Mean values ± SE of three replicates are presented. *p ≤ 0.05; **p ≤ 0.01; ***p ≤ 0.001.

Figure 2. Impact of foliar jasmonic acid treatment with and without aphid stress, on Chlorophyll a (A), Chlorophyll b (B), total chlorophyll content (C), and Carotenoids content (D) of two varieties of wheat i.e., Borlaug-2015 and Zincol-2015.

Values are per gram fresh weight of sample. Mean values ± SE of three replicates are presented. *p ≤ 0.05; **p ≤ 0.01; ***p ≤ 0.001.

Figure 3. Impact of foliar jasmonic acid treatment on Total soluble protein (A), phenolics (B), H₂O₂ (C) and MDA content (D) of two varieties of wheat i.e., Borlaug-2015 and Zincol-2015 with and without aphid stress.

Values are per gram fresh weight of sample. Mean values ± SE of three replicates are presented. *p ≤ 0.05; **p ≤ 0.01; ***p ≤ 0.001.