陇东黄土高原冬小麦地土壤杂草种子库初探

Preliminary study on soil seed bank of weeds in winter wheat field on Loess Plateau

土壤杂草种子库是农田发生杂草危害的主要根源,为了明确不同小气候条件和栽培管理措施对杂草种子库特征的影响,对庆阳市和天水市冬小麦地土壤种子库进行了比较研究。结果表明:庆阳市冬小麦土壤杂草种子有9科20种,其中田边、田中杂草量分别为2520、1964株/m2,稗草Echinochloa crusgalli数量较大,分别占47.54%和30.50%;天水市冬小麦土壤杂草种子有10科13种,其中田边、田中总出草数分别为3873、3506株/m2,小蓟Breea arvensis、蚤缀Arenaria serpyllifolia数量较大,在田边、田中分别占34.68%、28.27%和32.29%、32.63%。两地田边杂草发生总数均高于田中发生总数。其中,稗草、狗尾草Setariaviridis、灰绿藜Chenopodium glaucum是两地区农田的主要杂草和当前防除的重点,稗草和小蓟、蚤缀分别是庆阳市和天水市冬小麦地的优势种。通过分析两地冬小麦地土壤杂草种子库发生原因,提出了麦田杂草的防除策略。

Soil seed bank of weeds is the main resource of weeds in crop field. In order to explore the influence of microclimate and cultivation on seed bank of weeds, the study was conducted in Qingyang City and Tianshui City. The results showed that there were 20 species of weeds （belonging to 9 families） in Qingyang. The total number of weeds was 2 520 plants/m^2 and 1 964 plants/m^2 in the center and edge of field respectively, and the main weeds were Echinochloa crusgalli, which accounted for 47.54% and 30.50% of the total respectively. There were 13 species of weeds （belonging 10 families） in Tianshui. The total number of weeds was 3 873 plants/m^2 and 3 506 plants/m^2 in the center and edge of field respectively, and the main weeds were Herba cephalanoploris and Arenaria serpyllifolia, which accounted for 34.68% and 28.27% of the total in field center, and 32.29% and 32.63% of the total in field edge. The number of weeds in field edge was higher than that in field center. E. crusgalli, H. cephalanoploris and A. serpyllifolia were the dominant species in winter wheat field. In addition, the strategies for weed control were provided based on the research results.