温度对黄顶菊生长发育影响的研究

Study of temperature effect on growth and development of Flaveria bidentis

在梯度恒温条件下,研究温度对黄顶菊各生育期生长发育影响的试验结果表明,黄顶菊在12～42℃时均能萌发和出苗。温度高于16℃时,种子发芽率与出苗率随温度上升而显著增高;24～40℃时种子发芽率与出苗率均高于50%,28～36℃时均高于90%;温度达36℃以上时出苗率开始随温度上升而下降,温度达40℃时发芽率也逐渐降低。以叶片净光合速率(Pn)为代谢活力指标进行测定,结果表明,不同发育阶段黄顶菊的代谢活力从8℃到40℃逐渐增大,超过40℃后迅速减小。28～48℃现蕾开花期植株代谢活力明显高于苗期植株。

Effect of temperature on Flaveria bidentis （L.） Kuntze was studied at the condition of constant temperature in the lab, and it showed that the appropriate temperature range for germination and emergence of seeds was 12-42℃. When temperature was above 16℃, the germination rate increased with temperature raised; and the rate of germination and seedling emergence were both more than 50% at temperature range of 24-40 ℃, and more than 90% at 28-36℃. When temperature was above 36 ℃, the seedling emergence decreased with temperature raised; germination rate decreased at 40℃. Through testing of net photosynthetic rate （Pn）, metabolic activity of F/averia bidentis （L.） in different development stage increased at temperature range of 8 ℃ to 40 ℃, and it decreased rapidly when temperature was above 40℃. Metabolic activity in flowering stage was stronger than it in seeding stage at temperature range of 28 ℃ to 48℃.