Abstract:

In order to analysis the variation feature of plant height, leaf length, leaf width and branching number of Medicago polymorpha F₂ generation under different daylengths, this paper measured the flowering induction experiment of 2 different varieties of Medicago polymorpha from Haian Jiangsu and Wenling Zhejiang, respectively, under 10 h short daylength and 16 h long daylength using artificial climate chamber. The results showed that plant height, leaf length, leaf width of Medicago polymorpha F₂ generation obeyed normal distribution, while branching number disobeyed normal distribution under different daylengths; Medicago polymorpha F₂generation had highly significant difference(P < 0.01)in plant height, leaf length, leaf width trait and significant difference (P < 0.05) in branching number under different daylengths. Variation feature of branching number was obviously in Medicago polymorpha F₂ generation, which tended to be the female parent P₂ that branching number was 1. This paper also found that Medicago polymorpha was a long-day plant. Through this character, short daylength could be used to prolong growth period of Medicago polymorpha, improve target traits, increase the number of cutting and obtain high yield. In the breeding, varieties with high quality and high yield could be created through this character.

Key words: Medicago polymorpha, Photoperiod, F₂ generation, Agronomic character, Variation feature

摘要：

通过在人工气候室内模拟10 h短日照和16 h长日照2种光周期，对来自江苏海安和浙江温岭的2种性状差异明显的金花菜材料进行了不同光周期条件下的开花诱导试验，研究了不同光周期条件下金花菜杂交F₂代株高、叶长、叶宽和分枝数的变异特征。结果表明：在不同光周期条件下，金花菜F₂代株高、叶长和叶宽都服从正态分布，而分枝数不服从正态分布；在不同光周期条件下，金花菜F₂代株高、叶长和叶宽都表现为极显著差异（P<0.05），而分枝数表现为显著差异（P < 0.05）；在不同光周期条件下，金花菜F₂代分枝数的变异都最为突出并且都倾向于分枝数为1的母本P₂；本研究得出金花菜属于长日照植物。可以利用此特性进行短日照诱导延长金花菜生育期，改善目标性状，增加刈割茬数，获得高产。在金花菜的育种中，凭此特性还可以选育优质高产品种。

关键词: 金花菜, 日照条件, F₂代, 农艺性状, 变异特征