Factors controlling leaf area development in husk leaf of flint corn (Zea mays L.)

Abstract

A field experiment was conducted to study the factors that control leaf area development in husk leaves of flint corn especially the amount of sugars and N in cell wall. The ear leaf of Fi flint corn (N-19 × X-15), was subjected to ¹³CO₂ feeding 8 days before silking (DBS) under field conditions. The leaf area and the total sugars of the various cell components of the husk leaves were measured 13 DBS. The leaf area of the husk leaves at 9 DBS was about 8% of that at the silking stage. The total sugars of methanol-soluble fraction (cytosol) accounted for about 68% of the whole husk leaf, while hemicellulose and cellulose fractions constituted less than 10% at 9 DBS. At the silking stage, the total sugars of hemicellulose and cellulose fractions increased by 23% and 56% respectively. In the husk leaves, the percentage of plant ¹³C was about 6.6%, and ¹³C incorporated in the cellulose fraction increased by 74% at 24h after the ¹³CO₂ feeding. These results suggest that the development of the husk leaf area is closely related to the accumulation of cell wall materials such as hemicellulose and cellulose.