关键词: 紫薇, 紫薇, 无性系, 生长, 光响应曲线

Abstract: To clarify the soil toxicity of cucumber green mottle mosaic virus disease in the plough layer for greenhouse grafted watermelon, DAS-ELLSA was used for detecting the disease soil. The topsoil (0-5 cm deep) and deep soil (23-27 cm deep) were taken from roots of the infected plants and the adjacent plants, and 40 cm, 80 cm away from the roots to the edge of the membrane. The results showed that in the toxicity test of rhizosphere soil, healthy plants and plants with hidden disease had no virus. In virus infected plants, five sampling points including roots, edge membrane direction 40 cm and 80 cm from the roots, adjacent plants direction 40 cm and 80 cm from the roots, the topsoil virus carried rate was 100%, 80%, 70%, 40%, 20% in turn, deep soil virus carried rate was 80%, 50%, 50%, 40%, 30% in turn. In toxicity test on soil under different tillage methods, watermelon-rice-taro had no virus, continuous cropping of watermelon for two and three years all had high virus carried rate above 90% . The virus carried rate of topsoil biodegrade for one year, watermelon- rice- watermelon, watermelon- vegetable- watermelon, watermelon- vegetable- spring maize, atermelon- vegetable- rice, watermelon-sugarcane-rice was 50%, 42.86%, 35%, 30%, 24% and 20% in turn. So, topsoil virus carried rate was higher than that of deep soil, higher virus carried rate was found in soil which was closer to the root of the infected plant or with more luxuriant infected vine cover, crop rotation had degradation effect on virus infected soil.