青杨叶锈病发病规律及防治技术研究

Study of Occurrence Regularity and Control Technology on Leaf Rust of Populus cathayana

为了降低青杨叶锈病发病率和提高苗木质量,调查研究了叶锈病发病规律和不同扦插密度、药剂防治对发病率和病情指数的影响。结果表明:青杨叶锈病受扦插密度、地形地貌、降雨量和管理水平的影响,7月下旬～9月上旬为青杨叶锈病发病高峰期,侵染源主要是夏孢子。育苗时降低扦插密度和发病初期及早化学防治可有效降低发病率和病情指数,不同药剂中,发病初期叶面喷洒29%石硫合剂1000倍液防效最佳,发病率和病情指数分别为5. 58%和0. 10,较对照(CK)不喷洒任何药剂的发病率71. 74%和病情指数0. 56分别降低了92. 22%和82. 14%,差异均达到极显著水平(P <0. 01)。

In order to decrease morbidity of leaf rust and increase quality of Populus cathayana seedling, the occurrence regularity of leaf rust was investigated ,and the effect of different cutting density and pharma- ceutical control on morbidity and disease index was studied.The result showed that the leaf rust was affected by cutting density,landform,rainfall,and management level,it is onset peak period of leaf rust between late July and early September,the infection source is mainly summer spores.The morbidity and disease index were decreased effectively with cutting density decreased in nursery period and pharmaceutical control in early onset,the control efficiency is the best after 1000 fold solution of 29% calcium polysulphils was sprayed on leaf in early onset,the morbidity and disease index were 5.58% and 0.10 and 82.14% compare to CK (that doesn't use any bactericide)whose morbidity is 71.74%and disease index is 0.56,the difference reached to extremely significant level (P <0.01).