机构地区: 东北师范大学生命科学学院植被生态科学教育部重点实验室
出 处: 《草业学报》 2012年第3期303-307,共5页
摘 要: 通过对萹蓿豆不同发育阶段荚果和种子形态学特征和生理学特征的调查,来判断该物种硬实发生的时间及种子含水量与硬实之间的关系。结果显示,盛花后第33~36天荚果和种子几乎都变为棕色,种子的长、宽和厚显著减小,荚果大小变化也明显;此阶段荚果和种子鲜重在达到最大值后下降到最小,荚果和种子含水量达到最小值(20%左右);此时种子开始出现硬实,种子硬实率与种子含水量呈显著的负相关关系。因此,种子硬实受种子成熟度影响,而且与种子含水量有关。扁蓿豆荚果和种子的形态学特征和生理学特征的变化可以作为指示硬实发生的指标,其中荚果和种子的形态学特征可以作为判断种子发生硬实时间的快速有效的指标,但荚果和种子的干重不能作为指示硬实发生的指标。 Melissttus ruthenicus is a perennial legume and one of the most common fodder plants in northern China.It is a wild,high-quality forage grown mostly for hay,green forage,silage or seed production.However,seed hardiness is a major problem in the seeding of M.ruthenicus.This study evaluated the simple empirical relationship of time and seed hardiness by simultaneously analyzing pod and seed morphological and physiological properties.Pods were harvested at three-day intervals from the 9th day after peak anthesis(DAPA) until pod shattering.The pod and seed both lost green color and turned brown from the 33rd to 36th DAPA.The length,width and thickness of pod and seed differed significantly between sampling dates.Pod length and thickness declined significantly at the 33rd DAPA.Seed length,width and thickness significantly decreased from the 33rd to 36th DAPA.The fresh weight of pod and seed increased at an early developmental stage but decreased markedly thereafter.However,the dry weight of pod and seed increased significantly with sampling dates and reached a maximum at the 27th DAPA,then stabilized from the 27th to 36th DAPA(pod dry weight) and the 30th to 36th DAPA(seed dry weight).The water content of pods and seeds decreased significantly over the sampling dates and reached about 20% at the 33rd and 36th DAPA respectively.Seed hardiness occurred at the 33rd and 36th DAPA when seed water content was about 20%.There was a significant negative correlation between the percentage of hard seed and seed water content.In conclusion,growth stage and seed water content affected the occurrence of seed hardiness.Pod and seed morphological and physiological properties could be reliable and rapid indicators of seed hardiness,providing a simple way to judge the occurrence of seed hardiness.However,the dry weights of pods and seeds could not be used as indicators.