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白莲褐纹病又称莲叶斑病、黑斑病,是白莲产区的一种主要病害.近年来,随着白莲在我县种植面积的不断扩大和种植模式的不断更新,褐纹病的发生与危害程度呈上升和日趋严重的趋势,严重地影响着白莲的品质和产量.一、症状白莲褐纹病只为害叶片,病斑初为针头大小的黄褐色小点,后逐渐扩大至圆形或不规则形的褪绿色黄斑或褐色枯死斑,病斑边缘明显,周围具细窄的黄晕,叶背面病斑较正面略浅,多个病斑融合后,致使叶片上呈现大块焦枯斑,严重时除叶脉外,整个叶片布满病斑,致使半叶或整叶干枯.藕田初零星发病,后形成片似火烧状.二、发生规律病菌的菌丝体和分生孢子丛在病残体上或种藕株上存活和越冬,翌年产生分生孢子,借风雨传播进行初侵染,
Bailian brown stripes, also known as lotus leaf spot, black spot disease, is a major disease in the Bailian area.In recent years, with the continuous expansion of the planting area of Bailian in my county and planting patterns, Occurrence and the degree of harm is rising and increasingly serious trend, seriously affecting the quality and yield of white lotus I. Symptoms Bailian brown spot disease only leaves, the beginning of the lesion was the size of the needle-brown small dots, and then gradually expanded to round Shaped or irregular faded green or brown dead spots, the lesion edge is obvious, surrounded by narrow yellow halo, the back of the leaf lesions slightly lighter than the positive, after the fusion of multiple lesions, resulting in large leaf blight appeared dry Spots, in addition to severe veins, the entire leaves covered with lesions, resulting in half-leaf or whole leaf dry.On the first sporadic incidence of lotus fields, the formation of flakes like flames. Second, the occurrence of regular bacteria mycelium and conidia On the sick or on the lotus root plant survival and winter, conidia generated the following year, spread by wind and rain initial infection,