真菌性病害：拟脂点黄斑病

拟脂点黄斑病

1 症状:

首先在成熟叶表产生细小的黑色斑点，随后斑点相互连接，产生环绕病斑的晕圈。严重时，叶片掉落。

2 病原菌形态学特征:

S. roseus掷孢子肾形和卵形，3.5-4.5×6-9 μm；S. productus掷孢子肾形， 5.0-7.0×1.5-3.0 μm；S. corallinus掷孢子6.0-9.0×2.0-3.5 μm。

3 病原菌的生物学特性:

病菌最适生长温度为20℃左右，高于35℃或低于20℃菌丝生长缓慢。分生孢子萌发温度范围为5~35℃，最适温度15~25℃。

4 病害循环:

5 发病因素:

6 病害诊断:

目前已经设计出针对S. corallinus和S. productus种特异性引物对。使用引物对ITS-SpF (5’-CGG TCT CTT TTA GAC TCG AAG TGA A-3’)/ITS-SpR-4 (5’- GGT CGA ATA AAT AGG TTT GA-3’)特异性扩增S. productus得到目的条带391 bp。使用引物对ITS-ScF (5’-GTC TTA ATA CGA AAG AAA ACA ATC T-3’)/ITS-ScR (5’-GTT AAT GAT ATA GAG CTG AAG CT-3’)特异性扩增S. corallinus得到目的条带373 bp。

7 病害防治:

参考文献:

1) Furuya N, Adachi Y, Shiotani H (2013) Species-specific PCR primers for the detection of Sporobolomyces productus and S. corallinus, the causal agents of citrus pseudo greasy spot. Bulletin of the NARO Institute of Fruit Tree Science (16):13-18

2) Furuya N, Takashima M, Shiotani H (2012) Reclassification of citrus pseudo greasy spot causal yeasts, and a proposal of two new species, Sporobolomyces productus sp. nov. and S. corallinus sp. nov. Mycoscience 53 (4):261-269

3) Koizumi M (1986) Sporobolomyces roseus, a causal agent of citrus pseudo greasy spot (Nise-ohan-byo) and the infection process of disease. Annals of the Phytopathological Society of Japan 52 (5):758-765