光照强度和磷素水平对婆婆纳与离子草竞争的影响

Effects of Light Intensity and Phosphorus Application Rate on Competition Between Veronica Agrestis and Chorispora Tenella

通过盆栽试验,研究了不同的光照强度与P肥施用水平对两种重要麦田杂草婆婆纳与离子草的生长及其竞争关系的影响。结果表明,在弱光照下,婆婆纳和离子草的生长都相应减弱,但婆婆纳植株能萌发更多的叶片以适应弱光照条件;增施P肥,无论是在弱或强光照条件下都有利于婆婆纳的生长,但在弱光照强度下并不能显著促进离子草的生长。相比之下,离子草比婆婆纳更能忍受低P土壤养分条件,而后者却比前者更能忍受弱光照条件。因此,在土壤P素养分低,且光照强度较高时,离子草的相对竞争能力大于婆婆纳:而在土壤P素养分高时,无论是在弱或强光照条件下婆婆纳的相对竞争能力都要大于离子草。

Pot experiments were carried out to study effects of light intensity and phosphorus application rate on growth and competition of Veronica agrestis and Chorispora tenella. Results showed that low light intensity hindered growth of V. agrestis and C. tenella, but the former could develop more leaves to adapt to the weak light condition. Phosphorus application benefited growth of V. agrestis under either high or low light intensity, but the effect on C. tenella was not significant under low light intensity; Comparison between the two showed that C. tenella was more tolerant to low soil P supply, and V. agrestis to low light intensity. So, when soil P supply was lower, C. tenella was more competitive than V. agrestis under high light intensity. Then, when soil P supply was higher, V. agrestis was more competitive than C. tenella under any light intensity.