Jasmonic Acid-Mediated-Induced Resistance in Groundnut (Arachis hypogaea L.) Against Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae)

• Published in: Journal of plant growth regulation 2011-12, Vol.30 (4), p.512-523
• Main Authors: War, Abdul Rashid, Paulraj, Michael Gabriel, War, Mohd Yousf, Ignacimuthu, Savarimuthu
• Format: Article
• Language: English
• Subjects: Agriculture; Arachis hypogaea; Biomedical and Life Sciences; Catechol oxidase; Crops; Enzymes; genotype; Genotypes; Helicoverpa armigera; Herbivores; Host plants; Hydrogen peroxide; induced resistance; Infestation; Insects; Jasmonic acid; Lepidoptera; Life Sciences; Malondialdehyde; Noctuidae; peanuts; Peroxidase; Phenols; phytophagous insects; Plant Anatomy/Development; plant damage; Plant Physiology; Plant resistance; Plant Sciences; protein content; proteins; subtropics; Survival; Wounding
• ISSN: 0721-7595; 1435-8107
• DOI: 10.1007/s00344-011-9213-0

Jasmonic acid (JA) acts as a signal molecule to induce resistance in plants against herbivores and its levels are elevated in plants after wounding or insect damage. Groundnut is an important crop in many tropical and subtropical regions worldwide, but there is surprisingly little knowledge on its induced defenses against herbivores. The effect of JA as a spray on induced resistance in three groundnut genotypes, namely, ICGV 86699 (resistant), NCAc 343 (resistant), and TMV 2 (susceptible), against Helicoverpa armigera was studied. The activity of oxidative enzymes [peroxidase (POD) and polyphenol oxidase (PPO)] and the amounts of other host plant defense components [total phenols, hydrogen peroxide (H2O2), malondialdehyde (MDA), and protein content] were recorded at 24, 48, 72, and 96 h after pretreatment (1 day) with JA followed by infestation with H. armigera (PJA + HIN) and H. armigera infestation with simultaneous JA application (HIN + JA) to understand the consequences of induced resistance in groundnut. The plant damage, larval survival, and larval weights were also recorded. There was a significant increase in POD and PPO activities and in the amounts of total phenols, H2O2, MDA, and proteins in PJA + HIN- and JA + HIN-treated plants as compared to the plants treated with JA and infested with H. armigera individually and to untreated control plants. Among all the genotypes, the strongest induction of defense was observed in the ICGV 86699 genotype. It is concluded that pretreatment with JA and its application during low levels of insect infestation can increase the levels of host plant resistance against herbivorous insects and reduce the pest-associated losses in groundnut.