中文摘要：

通过体外产气曲线相减法来评价“农大108”玉米秸秆7个部位,即叶片（Leaf blade,LB）、叶鞘（Leaf sheath,LS）、茎皮（Stem bark,SB）、茎髓（Stem pith,SP）、茎节（Stem node,SN）、全株（Whole stalk,WS）和苞叶（Ear husk,EH）碳水化合物组分（A、B1、B2和NDS）体外动态发酵情况。结果表明,玉米秸秆不同部位之间碳水化合物含量存在着极显著差异（P〈0.0001）。碳水化合物组分A含量由高到低的顺序为茎皮〉茎节〉叶片〉全株〉叶鞘〉苞叶〉茎髓;碳水化合物组分B1含量由高到低顺序为苞叶〉叶鞘〉全株〉茎节〉叶片〉茎髓〉茎皮;碳水化合物组分B2含量以茎髓最多,茎皮最少。这三个组分各部位产气量高低顺序也与其含量一致。碳水化合物组分中性洗涤可溶物（Neutral detergent soluble,NDS）含量以茎皮、茎节中含量最高,茎髓最少,但其产气量却以茎节最高,苞叶次之,茎髓最少。提示应用产气曲线相减法能够有效地评价玉米秸秆中各部位碳水化合物各组分的动态发酵情况。

英文摘要：

The aim of this experiment was to evaluate the fermentation kinetics of carbohydrate fractions （A, B1, B2 and NDS） of 7 various sections of corn stalks of ＂Nongda 108＂, including leaf blade （LB）, leaf sheath （LS）, stem bark （SB）, stem pith （SP）, stem node （SN）, whole stalk （WS） and ear husk （EH）. The results showed that carbohydrate fractions were significantly different （P 〈0. 000 1） among various sections of corn stalks. Content of carbohydrate fractions A from high to low rank as follows： SB 〉 SN 〉 LB 〉 WS 〉 LS 〉 EH 〉 SP; content of carbohydrate fractions B1 as follows： EH 〉 LS 〉 WS 〉 SN 〉 LB 〉 SP 〉 SB; SP had the highest content of carbohydrates fraction B2, while SB had the lowest content. Gas productions of various sections of corn stalks for carbohydrates three fractions with rank from high to low values were consistent with their contents. SB and SN had the highest content of neutral detergent soluble （NDS）, while SP had the lowest content, however, SN had the highest gas production,followed by EH, and SP content were the lowest. The curve subtraction technique represents a valid approach to evaluate the fermentation kinetics of carbohydrate fractions of various sections of corn stalks.