外来恶性杂草假高粱种子萌发特性研究

 【目的】明确外来恶性杂草假高粱（Sorghum halepense）种子的萌发特性。【方法】研究颖片、温度、光照、GA3及土层深度对其种子萌发的影响。【结果】颖片对假高粱种子的萌发具有物理阻碍和化学抑制作用，是导致其种子休眠的主要原因。假高粱种子萌发的最适温度为30℃，在25℃/35℃、12 h/12 h的变温方式下也能较好地萌发。假高粱种子的萌发需要一定的光照条件，在连续光照或12 h光照条件下，其种子萌发率较高。GA3能显著促进假高粱种子的萌发，其最适浓度为1.16 mmol•L-1。0～4 cm的土层适宜假高粱种子的萌发，随着土层深度的增加其萌发率显著降低。【结论】假高粱种子的萌发受环境条件影响较大，通过采取有针对性的管理措施调控假高粱的萌发生长，可以有效遏制其危害蔓延。

Seed Germination Behavior of a Worst Exotic Weed Species of Johnsongrass(Sorghum halepense)

【Objective】 To determine the germination characteristics of Johnsongrass (Sorghum halepense), a worst exotic weed species, 【Method】 the effects of glume, temperature, light, GA3 and soil depth on seed germination were studied. 【Result】 The results showed that the glume of Johnsongrass had mechanical obstructing and chemical inhibiting effects on seed germination, and it was the major cause of seed dormancy. Germination of Johnsongrass seeds was best at 30℃, and also better under the daily temperature change of 25℃/35℃ for 12 h/12 h. Light was preferred for seed germination, the rate was relatively higher under 12 h light or continuous light condition. GA3 could significantly stimulate the germination of Johnsongrass seeds and the optimum concentration was 1.16 mmolּL-1. Seeds placed in 0~4 cm soil layer was ideal for germination of Johnsongrass, but the germination rate decreased markedly with the increase of soil depth. 【Conclusion】 By implementation of corresponding management strategies to regulate and prevent the seed germination, the spreading and infestation of Johnsongrass could be well controlled.