不同收获期扁穗雀麦的种子特性

Seed characteristics of Bromus catharticus at different harvest times

为明确扁穗雀麦(Bromus cartharticus)在不同收获期(花后8、13、19、25、32、36和42 d)种子含水量、大小、萌发和电导率的变化,以“江夏”和“黔南”两品种为试验对象进行研究。结果表明,在武汉地区,随着扁穗雀麦种子的成熟,种子含水量逐渐下降,而千粒重变化与之相反并于花后32 d趋于稳定。不同时期收获的扁穗雀麦种子发芽率、发芽势、发芽指数和活力指数除在花后42 d略有下降外,其他时间基本表现为逐渐升高的趋势,但花后32–42 d各指标差异不显著(P>0.05)。种子成熟过程中,两品种电导率由花后8 d的379.45μs·(cm·g)^–1和340.90μs·(cm·g)^–1持续下降,到花后42 d减少超过84%且花后8–42 d差异显著(P<0.05)。综合考虑,“江夏”和“黔南”扁穗雀麦在花后32–36 d、含水量分别为26%~45%和32%~49%时收获最佳。

The study was to clarify the changes in seed moisture content,thousand-seed weight,seed germination,and conductivity of Bromus catharticus at different harvest times(8,13,19,25,32,36,and 42 d after the onset of the flowering period).Jiangxia and Qiannan varieties were studied as test materials.The results showed that the seed moisture content of the two varieties decreased gradually with seed maturation;however,the change in thousand-seed weight showed the opposite trend and tended to stabilize at 32 d after flowering in the Wuhan area.Germination rate,germination potential,germination index,and vigor index of the seeds harvested at different stages showed a gradual increasing trend,except on day 42 after flowering,when the values decreased slightly.However,no significant differences were observed for any index from 32 to 42 d after flowering(P>0.05).During the seed maturation process,the conductivity of the two varieties decreased continuously from 379.45μs·(cm·g)^–1 and from 340.90μs·(cm·g)^–1,respectively,at day 8 after early flowering to more than 84%by day 42.The differences were significant at 8–42 d(P<0.05).Taking this into consideration,the best harvest time for B.catharticus was between days 32 and 36 after flowering,and the seed water content of Jiangxia and Qiannan was 26%~45%and 32%~49%,respectively.