海南省入侵杂草假高粱种子萌发特性研究

Seed Germination Traits of Invasive Weed Sorghum halepense in Hainan Island

为了解环境对假高粱(Sorghumhalepense)种子萌发的影响,对海南岛假高粱种子的萌发特性进行了研究。结果表明,假高粱种子的萌发率较高,均在85%以上,在昼夜温度35℃/25℃下的萌发时间最短(2.64 d);浓硫酸处理可提高种子萌发率;浓硫酸处理、赤霉素浸泡和研磨均能缩短种子萌发时间;种子在土壤表层的萌发率最高,随着埋藏深度的增加,种子萌发率下降,萌发时间增加。灾变区与非灾变区种子在不同温度、打破休眠方式、埋藏深度的萌发率和萌发时间均无显著差异。可见,环境在一定程度上影响了假高粱种子的萌发,高温和土壤表层的种子有较高的萌发率和较快的萌发速度。海南岛的假高粱种子萌发率较高且萌发生态幅较宽,是近年来其在海南突发成灾的重要原因之一,因此,在假高粱花果期之前加强控制,减少种子的成熟和传播。

In order to reveal the effect of environment condition on seed germination of Sorghum halepense,its germination characters were studied in Hainan Island.The results showed that the germination rate of S.halepense seeds was high with more than 85%,and the germination time was the shortest(2.64 d)under day and night temperature at 35℃/25℃.The seeds treated with 98%concentrated sulfuric acid could improve germination rate.The seed germination time was shortened treated with concentrated sulfuric acid,gibberellin and grinding.The seeds on the soil surface had the highest germination rate,and germination rate decreased and germination time increased with burial depth.Among different treatments,such as temperature,dormancy breaking and burial depth,there were no significant differences in germination rate and germination time of S.halepense seeds between outbreaking and non-outbreaking regions.Therefore,environmental conditions could influence germination of S.halepense seeds,and the seeds under high temperature and on the soil surface had high germination rate and short germination time.Seeds of S.halepense in Hainan Island had high germination rate and wide ecological breadth of germination,which was one of important reasons for its sudden disaster in Hainan in recent years.So,the strengthen control before flowering of S.halepense,reduce seed maturation and dissemination.