Changes in Leaf Phenolics and Chlorophyll Content of Maize Inoculated with Glomus intraradices Upon Spodoptera frugiperda Infestation

Maize, the third important cereal crop, is severely affected by Spodoptera frugiperda (fall armyworm). Arbuscular mycorrhizal fungi (AMF) colonized crops are shown to tolerate insect infestation because of systemic priming of defence against insect attack. The present study aimed to examine the effect of various doses of AMF (Glomus intraradices) inoculation on triggering tolerance against S. frugiperda infestation in maize. The total phenolics and the chlorophyll content of insect uninfested leaves obtained from AMF applied and insect attacked treatments were higher over AMF uninoculated plants upon insect attack. However, a greater concentration of phenolics and chlorophyll was observed in plants treated with maximum spore inoculum of 5 per seed. Similarly, plant biomass was also greater in the same treatment even after S. frugiperda infestation. These observations indicate the importance of AMF in sustaining maize growth and health during S. frugiperda attack.