Serial Measures of Dry Matter Accumulation and Forage Quality of Leaves, Stalks, and Ears of Three Corn Hybrids1

Abstract

AbstractDry matter yields and forage quality of plant components (leaf, stalk, and ear) through maturity could vary among corn (Zea mays L.) hybrids. These potential differences could affect total forage quality yield and the hybrid choice for corn silage use. To compare plant composition, total plant dry matter, and forage quality among corn hybrids from flowering to physiological maturity, we studied leaf, stalk, and ear dry matter production and forage quality of three corn hybrids with maturity. Three corn hybrids, ‘Nebr. 611’, ‘Nebr. 612’, and ‘Nebr. 712’, were grown under field conditions with optimum agronomic conditions on a Sharpsburg silty clay loam (Typic Argiudolls) soil and harvested at six kernel development stages within 9 weeks following flowering during 1973 and 1974. All forage was separated for leaf, stalk, and ear dry matter production, and analyzed for crude protein, and in vitro dry matter disappearance (IVDMD). Total plant dry matter production increased at most harvests both years for all hybrids. Hybrid 712 yielded significantly more forage than 611 and 612 for most harvests. Stalk dry matter production declined over the harvests both years while leaf production increased during 1973. Leaf production remained the same over the harvests in 1974 for hybrids 611 and 612. Ear dry matter production increased at each harvest for all hybrids both years. Leaf crude protein was twice as large as stalk crude protein and declined over all harvests for the leaf component. Percent crude protein of ears declined through the first three harvests only. No hybrid differences were detected in percent crude protein of the three yield components. Leaf IVDMD was higher than that of stalk IVDMD. Rate of IVDMD decline was greater in stalks than leaves. Leaf IVDMD was consistently higher in 712 than 611 or 612. Little change occurred in ear IVDMD over the six harvests, however, the values were significantly greater in 1974 than 1973. The greatest plant protein and IVDMD yield occurred at the last harvest, physiological maturity, both years for all hybrids. Variation was detected among hybrids for total plant dry matter and plant component yields but less variation was detected among hybrids in forage quality for each plant component.