Diferulate content of maize sheaths is associated with resistance to the Mediterranean corn borer Sesamia nonagrioides (Lepidoptera: Noctuidae).
The leaf sheaths of selected inbred lines of maize (Zea mays L.) with variable levels of stem resistance to the Mediterranean corn borer Sesamia nonagrioides (Lefèvbre) were evaluated for antibiotic effect on insect development. Phytochemical analyses of leaf sheaths were conducted for cell wall phenylpropanoid content to gain a better understanding of maize-resistance mechanisms. Laboratory bioassays established that sheath tissues from different genotypes significantly affected the growth of neonate larvae. Three hydroxycinnamates, p-coumaric, trans-ferulic, and cis-ferulic acids, and three isomers of diferulic acid, 8-5', 8-O-4', and 8-5' b (benzofuran form), were identified. Significant negative correlations were found between larvae weight and diferulic acid content for six genotypes. These results are in agreement with previous studies concerning the role of cell wall structural components in stem borer resistance.
Santiago
Rogelio
R
EUET Forestal, Universidad de Vigo, Campus Universitario Pontevedra, E-36005 Pontevedra, Spain. rsc@uvigo.es
Butrón
Ana
A
Reid
Lana M
LM
Arnason
John T
JT
Sandoya
German
G
Souto
Xose C
XC
Malvar
Rosa A
RA
D000818:Animals; D002473:Cell Wall / Q000737:chemistry; D003373:Coumaric Acids / Q000032:analysis* / Q000737:chemistry; D007814:Larva; D007915:Lepidoptera; D010572:Pest Control, Biological; D010666:Phenylpropionates / Q000032:analysis* / Q000737:chemistry; D018547:Plant Stems / Q000737:chemistry; D003313:Zea mays / Q000737:chemistry*
D003373:Coumaric Acids; D010666:Phenylpropionates; C516502:diferulic acid