四川省杂交水稻种子寄藏真菌研究

A Survey of Seed-Borne Mycoflora on Hybrid Rice in Sichuan

为明确杂交水稻种子携带真菌种类、探讨种子健康状况，采用洗涤、吸水纸保湿培养等方法检测来源于四川省的22个杂交水稻种子样品。结果表明，杂交水稻种子平均夹带有3.65％的以稻粒黑粉病粒和稻曲病粒为主的病粒和菌核，每克种子真菌孢子负荷量平均达1.65×10^5个。吸水纸保湿培养法从22个样品获得1698个真菌菌株，种子带菌率为15％-93％，平均带菌率为38.56％。这些真菌菌株分属于至少27个属，其中以Aspergillus（占总菌株的11.66％）、Tilletia horrida（10.54％）、Fusarium（9.36％）、Rhizoctonia solani（8.07％）、Penicillium（7.54％）、Alternaria（4.95％）、Rhizopus（4.59％）、Ustilaginoidea virens（4.18％）、Sclerotium（4.12％）、Mucor（3.36％）这10个属种为优势菌群，合计占总菌株数的68.37％。杂交水稻种子寄藏真菌类群具有多样性，没有发现新的水稻种子寄藏真菌。

This study was designed to identify seed-borne fungi on hybrid rice （ Oryza sativa L. ） in Sichuan. Twenty-two seed samples were collected for mycological analysis by the washing, standard blotter tests. It was found that the disease seeds and sclerotia,mainly kernel smut and false smut seeds,could account for 3.65% of the total seeds and each gram seeds burthen 1.65 x 105 spores. Paddy rice contained high levels of a wide variety of fungi. 1698 fungal isolates which belong to 28 or more genera, were identified by standard blotter method. The most common fungi isolated were Aspergillus （ 11.66% of all fungal isolates ）, Tilletia horrida （ 10. 54 % ）, Fusarium （9. 36 % ）, Rhizoctonia solani （ 8.07 % ）, Penicillium （ 7.54 % ）, Alternaria （4.95 % ）, Rhizop groups us （4.59 % ）, Ustilaginoidea virens （ 4. 18 % ）, Sclerotium （ 4. 12% ）, Mucor （ 3.36% ） species. Although of seed-borne fungi from hybrid rice were diverse, no new seed-borne fungi was discovered.