Spatial Distribution and Influencing Factors of Canker and Root-Rot Di-seases of Carya cathayensis
In order to investigate the spatial distribution and influencing factors of the main diseases of Carya cathayensis in Lin'an District,Hangzhou City,Zhejiang Province,this study investigated the spatial distribution of canker and root-rot diseases of Carya cathayensis forest were surveyed and counted in 7 towns in Lin'an District.Effects of soil pH values,soil types,fertilizer treatments and weeding methods on disease index of Carya cathayensis and the influence of the latter three factors on soil pH values were also analyzed.The results showed that in a total of 279 hickory forest plots in 7 townships in Lin'an District,the canker and root-rot disease index were significant-ly positively correlated.Among them,the disease was the most serious in Daoshi Town.The disease index of the two diseases were all above 80.1 in some hickory forests,and almost the whole plant died.There were 239(85.7％)sample plots whose soil was acidic(pH value＜7.0),and the stronger the soil acidity,the higher the dis-ease index of the two diseases.In the hickory forest with soil pH values between 4.50～5.49,the disease index of canker and root-rot diseases were 34.4 and 48.0,respectively,which were significantly higher than the soil pH val-ues range of 6.50～7.49.The disease index of canker and root-rot diseases of the hickory forest with lithological soil was 39.04 and 45.89 respectively,which were significantly higher than those in red and yellow soil hickory forests.The disease indexes of canker and root-rot diseases of hickory forests with inorganic fertilizer were 47.9 and 55.1,respectively,which were significantly higher than those with 50％organic fertilizer instead of chemical fertilizer and non-fertilized forests.The disease index of canker and root-rot diseases in the chemical weeding hickory forest were 35.0 and 45.5,respectively,which were significantly higher than that of the physical weeding and non-weeding forests.Stepwise regression and correlation analysis showed that the decrease of pH value had the greatest effect on the improvement of the disease index of the two diseases among the four influencing factors.Both the application of inorganic fertilizer and the use of chemical weeding method will significantly reduce the soil pH value and increase the incidence of two hickory diseases.
Carya cathayensisCanker diseaseRoot-rot diseasepH value
万方数据
维普
