Abstract: In Vitro gas production method was used to study gas production of maize stalk of three varieties at four different growth stages.This study combined grain yield and related nutrition quality analysis to provide a reasonable evaluation for whole maize plant during feeding and provide a reference to stalk-based livestock production.Results indicated that the method effectively simulated maize stalk digestion processes in livestock rumen.Gas production of maize stalk at different growth stages ranked as booting>anthesis>filling>maturity.Three varieties had different gas production with increased growth period.At the booting stage,gas production was the greatest for all tested varieties compared to other stages.The faster gas producing rate was observed at 0~24 h,then declined after 36 h.At complete maturity,variety FN1 had the greatest accumulated gas production,102.7% and 178.8% higher than that of ZHD958 and ZD2,respectively.Its gas-producing peak appeared at 3~9 h and finished after 24 h,while others peaked at 0~3 h and finished after 12 h.This reflected the effect of growth stage on gas-producing rate.According to maize stalk and grain nutrition analysis at maturity,FN1 had higher crude protein,nitrogen free extract,acid detergent fiber,soluble sugar,stalk yield and grain protein content than the other varieties.Therefore,under selected corn grain yield,FN1 had higher stalk feeding value and more application prospect in dual-purpose maize production.

Key words: In Vitro gas production, Maize stalk, Nutritional value, Digestion

摘要： 用体外产气法测定了3种不同秸秆成熟型玉米(Zea mays L.)品种不同生育期的秸秆产气量,结合成熟期籽粒产量及相关营养品质分析,以期对粮饲兼用型玉米全株饲用效果作出合理评价,为发展秸秆养殖业提供参考。结果表明:采用体外产气法能够有效模拟玉米秸秆在动物瘤胃基本消化过程,不同生育期秸秆产气量表现出拔节期>开花期>灌浆期>完熟期的趋势,且随着生育期的推进品种间差异愈明显,拔节期各品种秸秆产气量均为最高且品种间无显著差异。在0～24h内产气速率较快,36h以后趋于平缓至结束;完熟期富农1号累积产气量最高,分别较郑单958和中单2号高出102.7%和178.8%,且产气速率峰值出现在3～9h,持续24h后结束,而郑单958和中单2号峰值出现在0～3h,且12h后结束,反映出不同秸秆成熟活性差异对产气量及产气速率的影响。根据对成熟期玉米秸秆成分及籽粒营养品质分析表明,粗蛋白(CP)、无氮浸出物(NFE)、酸性洗涤纤维(ADF)和可溶性糖等成分的含量,以及秸秆产量和籽粒蛋白质含量均表现为富农1号比其他2个品种高。因此,在保证一定玉米籽粒产量的基础上,富农1号秸秆具有较高饲用价值,在发展粮饲兼用玉米产业中具有较好的推广应用前景。

关键词: 体外产气法, 玉米秸秆, 饲用价值, 消化