木麻黄根区土壤理化特性及酶活性与青枯病发生关联分析

为探究木麻黄(Casuarina spp.)根区土壤理化特性及酶活性与青枯病发生的关系,进而为加强生物防治提供参考.选取位于广东省潮州市饶平县大埕镇、湛江市吴川市塘尾镇和湛江市徐闻县前山镇的3个木麻黄人工林为研究对象,在每个林分下分别设置3个样地,每个样地采集木麻黄青枯病感病植株和健康植株根区土壤各3份,共54个土壤样...

Correlation Analysis of the Occurrence of Bacterial Wilt and Physicochemical Properties and Enzyme Activity of Root-Zone Soil of Casuarina spp.

In order to investigate the relationship between the occurrence of bacterial wilt in Casuarina spp. forest and soil physicochemical properties and enzymatic activity, this study selected diseased and healthy plants of Casuarina spp. from Dacheng Town, Raoping County, Chaozhou City of Guangdong Province, Tangwei Town, Wuchuan City and Qianshan Town, Xuwen County of Zhanjiang City. A total of 54 soil samples were collected and the physicochemical properties and enzyme activity in the soil were measured. The results showed that the disease index was 1.33 in Raoping, 5.47 in Wuchuan, and 10.53 in Xuwen. As part of the data analysis, the three sampling plots were classified according to the disease index, from light to severe, as Raoping plot(level 1), Wuchuan plot(level 2), and Xuwen plot(level 3). Soil pH value, SOM, TN, TP, TK, AN, AP, and AK content in the root-zone of diseased plants of Casuarina spp. were lower than those of healthy plants. There were significant differences in TN contents(P<0.05), and the differences in SOM, AP, TK, AK and AN contents were highly significant(P<0.01). The contents of URE, ACP, CAT, POD and PPO in the roots of healthy plants of Casuarina spp. were higher than those in diseased plants. The the contents of INV in the root had highly significant negative correlations with the TK and AP content in the soil(P<0.01), and highly significant positive correlation with the content of PPO(P<0.01), and negatively correlations with ACP, INV, CAT, and POD activity. The soil PPO activity of different disease degrees were as follows: level 1(23.45 mg·g^-1·h^-1), level 2(30.43 mg·g^-1·h^-1), and level 3(59.63 mg·g^-1·h^-1). In summary,PPO activity can be used as an indicator of the degree of bacterial wilt infection of Casuarina spp.. The mechanism of soil physicochemical properties and enzymatic activity against bacterial wilt is complex and thus needs to be further investigated. Future studies may prove it at the molecular and physiological levels, explore its optimal concentration to resist bacterial wilt, take into account other elements, and examine combined effects of multiple elements. From the perspective of soil microbes, future research should examine the prevention of plant diseases in collaboration with biocontrol bacteria.