28种禾本科植物种子形态学特征及其萌发对绵羊瘤胃消化的反应

采用瘘管羊瘤胃瘘管尼龙袋法,对北疆地区常见的28种禾本科植物种子进行不同时间段的瘤胃消化处理,对处理前后种子的长、宽、厚、形状指数、百粒重和萌发率进行了测量,研究种子对绵羊瘤胃消化的反应,以期丰富北疆地区植物种子消化道传播的内容.结果表明: 除臭草、剪股颖、鳞茎早熟禾、猫尾草和小麦以外,其余23种植物的种子均为椭圆或扁平状种子;小麦和燕麦种子百粒重分别为3.52和1.69 g,其余种子的百粒重均为0.01～1 g,属中等或偏小类型.种子经瘤胃消化后,颜色变深,种子结构被破坏,种子的芒、稃和颖等附属结构的长度随消化时间的延长逐渐减小;种子长、宽、厚、百粒重随消化时间的延长呈逐渐减小趋势,但变化不显著;种子经绵羊瘤胃消化后,萌发率显著降低,经瘤胃消化6 h后,除鹅观草和燕麦种子萌发率降为0外,其余26种植物仍有部分种子保持活力.

Seed morphology and effects of sheep rumen digestion on seed germination of 28 Gramineae plants.

An experiment was undertaken to compare the morphological characteristics of seeds of 28 Gramineae plants which widely distributed in north Xinjiang and to study their digestion in the rumen of sheep. After determining their morphological characteristics including seed length, width, height, seed shape index, 100-seed mass, and seed germination percentage, seeds were put into nylon bags and then placed in the rumen of sheep through a fistula. The bags were removed at different times to determine the morphological characteristics and seed germination rates. The results showed that 23 plant seeds were all elliptic or flat types except for Melica scabrosa, Agrostis ma-tsumurae, Poa bulbosa, Phleum pratense and Triticum aestivum. 100-seed mass of T. aestivum (3.25 g) and Avena sativa (1.69 g) were >1 g, and the 100-seed mass of the other seeds ranged from 0.01-1 g, indicating they were all medium or small type seeds. The color of seed coat was deepened, seed structure was destructed, and the lengths of seed appendages, i.e., awn, lemma and glume were decreased with increasing digestion time. Seed length, width, height, 100-seed mass were decreased with increasing digestion time, but the changes were not significant compared with the non-digested seeds. The seed germination percentages were extremely decreased after sheep rumen digestion. After 6 h of sheep rumen digestion, the germination rates of the seeds of R. kamoji and A. sativa were decreased to 0, and part of the seeds of other 26 plants still had some vigor.