通过不同短日照处理玉米近缘种墨西哥大刍草,研究短日照对其生长发育的影响,结果表明:短日照处理可以诱导墨西哥大刍草提前抽雄开花;墨西哥大刍草接受短日感应的临界叶龄、日照长度、短日诱导天数分别为6叶龄、13h、15d;对墨西哥大刍草进行短日诱导(日照长度为12h),以处理25d主茎雄花分枝数最多和分枝最长,因此,以饲草玉米种子生产为目的,对墨西哥大刍草进行短日诱导,应从6叶龄开始进行25d以上每天12h的连续短日照处理最为有效。 The effects of short daylight on its growth and development were studied by different short day treatments. The results showed that the short daylight treatment could induce the flowering of Mexican draft grass ahead of flowering; the Chinese herbaceous grass received the critical of short day induction The days of leaf age, the length of sunshine and the days of short days were 6-leaf-age, 13-h and 15-d, respectively. The short-day induction of Radix sophia was carried out for 12 days Therefore, in order to forage maize seed production for the purpose of short-day induction of Mexican grass, grass should be carried out from 6 leaf age for more than 25d 12h daily continuous short-day treatment is most effective.