通过盆栽试验,研究了不同有机质含量的土壤中施用不同用量生物有机肥对棉花黄萎病的发病率和病情指数、植株干重、土壤微生物数量及微生物量的影响。结果表明:随着施用量的增加,不同有机质含量的植株干重和土壤微生物量也在的增加,而土壤微生物数量则呈现先上升后下降的趋势。其中高有机质含量的土壤中施用10~20g/kg生物有机肥处理最大,中、低有机质含量的土壤中施用20~30g/kg最高。施用生物有机肥能显著降低棉花黄萎病病情指数,且防治效果在21.7%~75.0%之间。其中高有机质含量的土壤施用20g/kg防病效果最高,为52.6%;中、低有机质含量的土壤施用30g/kg效果最高,分别为75.O%、55.0%。总之,科学合理的施肥,不仅能够更好地使土壤微生物区系向健康、合理的方向发展,而且最大程度上降低棉花病情,为棉花生长提供良好的保障。
Rapidly measuring the soil water content in the field is very important to the water and fertilizer manage- ment. In this paper, we using RR- 7730M soil hygrometer, conducted rapid determination in the field, and simulated experiment of different water content soil in the lab, compared with the results of classical drying oven method. The re- sults showed that in the field and indoor simulation, rapid measurement using RR - 7730M soil hygrometer and drying oven method both reach significant correlation. The correlation coefficients respectively are r = 0. 857 ** (n -= 240) and r = 0. 982 ** ( n = 27). The method of rapid measurement is feasible and practical. It is worthy to be popularized.