Breeders have selected for European corn borer [Ostrinia nubilalis (Hubner)] (ECB) resistance for manyears and this may have led to higher concentrations of cell wall carbohydrates and lignin in stalks and leaf sheaths of maize (Zea mays L.). Our objectives were to evaluate the compositional changes accompanying divergent selection for cell wall constituents in three maize populations and to determine whether these changes were associated with changes in ECB resistance. Population BS9(CB) had undergone five cycles of S1 family selection for increased first‐ and second‐generation ECB resistance. Cycle 2 of BS9(CB) also underwent one cycle of divergent S1 selection for neutral detergent fiber (NDF) and lignin concentrations in the stalk and leaf sheath. Populations WFISILO and WFISIHI underwent two cycles of S1 family selection, respectively, for low and high NDF, acid detergent fiber (ADF), and lignin. Whorl samples were collected at the time of first‐generation infestation. Stalks, leaf sheaths, and leaf blades were sampled following second‐generation infestation. Selection for increased ECB resistance in BS9(CB) increased NDF, ADF, and lignin concentrations in stalks and leaf sheaths. Selection for high NDF and lignin concentrations in BS9(CB) C2 produced materials with greater second‐generation ECB resistance than did divergent selection for low concentrations. Selection for decreased NDF, ADF, and lignin in WFISILO decreased second‐generation ECB resistance. Selection for increased NDF, ADF, and lignin in WFISIHI did not influence ECB resistance, however. In general, there was an association between plant cell wall composition and ECB resistance, but genetic background influenced the relationship.

The concentration of phenolic acids and in situ disappearance of cell wall (CWISD) of normal maize and bm1, bm2, bm3 and bm4 mutants were evaluated in whole stem and stem sections at the silking and silage stages. At the silking stage, the CWISD of bm1 was similar to that of normal maize while that of bm2, bm3 and bm4 was greater; p‐coumaric acid and lignin concentrations were lower in the mutants while ferulic acid varied little. At the silage stage, the composition was slightly altered but the CWISD of the mutants was notably reduced, possibly because of condensation reactions occuring with ageing. The mid‐internode was the most similar in composition and degradability to the whole stem. © 1999 Society of Chemical Industry

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