Gene

Lepidoptera genitalia

Ecology

Cultivar

Biology

Noctuidae

Biochemistry

Botany

Trichome

Plant defense against herbivory

Herbivore

Larva

Genetics

Interspecific competition

Insect

Oryza sativa

Plant Cell & Environment

Interspecific New Rice for Africa (NERICA) varieties have been recently developed and used in Sub‐Saharan Africa but herbivore resistance properties of these plants remain poorly understood. Here we report that, compared to a local Japanese cultivar Nipponbare, NERICA 1, 4 and 10 are significantly more damaged by insect herbivores in the paddy fields. In contrast to high levels of leaf damage from rice skippers and grasshoppers, constitutive and induced volatile organic compounds for indirect plant defense were higher or similar in NERICAs and Nipponbare. Accumulation of direct defense secondary metabolites, momilactones A and B, and p ‐coumaroylputrescine (CoP) was reduced in NERICAs, while feruloylputrescine accumulated at similar levels in all varieties. Finally, we found that Nipponbare leaves were covered with sharp nonglandular trichomes impregnated with silicon but comparable defense structures were virtually absent in herbivory‐prone NERICA plants. As damage to the larval gut membranes by Nipponbare silicified trichomes that pass intact through the insect digestive system, occurs, and larval performance is enhanced by trichome removal from otherwise chemically defended Nipponbare plants, we propose that silicified trichomes work as an important defense mechanism of rice against chewing insect herbivores.

Nonglandular silicified trichomes are essential for rice defense against chewing herbivores