玉米茎剪断力研究

玉米秸秆是东北农牧交错地区冷季重要饲料来源。决定玉米秸秆饲料品质的结构部位是茎，茎的剪断力直接反映其物理特征。本文选择四密21、农大3138和登海1号3个玉米品种进行试验。将玉米植株叶片、叶鞘及果穗等去除，按50 cm高度分段，研究了玉米茎不同高度处剪断力随时间变化情况。研究结果表明，随着时间推进，茎的剪断力逐

Shearing Force of Maize Stem

Maize stalk is important forage resource in cold season in ecotone between agriculture and animal husbandry. Quality of stalk forage is determined by physical characteristic of the stem, and shearing force directly indicates physical characteristic of the stem. Three maize cultivars were selected for the experiment in order to utilize maize stalk better. Temporal dynamics of shearing force of maize stem of different height were studied. The results showed that shearing force of the stem increased with maize growth and development. The shearing force of the lower part of stem was larger than that of the higher one. Relationship between shearing force and chemical constituents were also studied by using maize cultivar Denghai 1. Shearing force of maize stem increased with the decrease of moisture content. There was negative correlation between shearing force and moisture content in stem. Shearing force increased with the increase of acid detergent lignin (ADL), hemicellulose and cellulose content. There was positive correlation between shearing force and acid detergent lignin, hemicellulose and cellulose content. It was evident that digestive rate of maize stalk utilized as forage decreased with maize development, especially in the late of maize development.