小麦种子黑胚对发芽的影响及病原菌鉴定的研究

Studies on the Effect of Black Point of Wheat Seed on Germination and the Identification of Its Pathogens

对6个小麦品种种子的黑胚进行了研究。结果表明:1.不同品种种子黑胚率不同,同一品种成熟期间因大气湿度提高黑胚率显著增加;2.黑胚严重的品种一般易穗发芽,同品种黑胚种子穗发芽率高于白胚种子,已经穗发芽的种子仍具有再发芽能力,但其发芽率明显低于正常的未穗发芽种子;3.同品种黑胚种子的千粒重明显高于白胚种子,这与两类种子于同株不同穗和同穗不同小穗中的分布密切有关;4.小麦种子黑胚经鉴定证明是一种真菌性病害,主要是链格孢菌(Alternaria alternata)所致,且多于小麦成熟期(开花后25—30天)侵染种子。

The formation and characteristics of wheat(Triticum aestivum L.)seed with blackpoints were studied on 6 varieties.The results showed:(1)The frequency of black point for-mation varied with different varieties and increased obviously as the humidity of atmos-phere increased during the maturation period of wheat.(2)Sprouting of seeds on ears wasmore often in the varieties with high frequency of black point formation.The percentage ofsprouting on ears in the seeds with black point was higher than that in the normal seeds ofthe same variety.Seeds already sprouted on ears retained the potential to regerminate,al-though their germinating rate was lower than that of the seeds not sprouted on ears.(3)The thousand-grain weight of seeds with black point was obviously higher than that ofthe normal seeds in the same variety.It correlated to the distribution of the two kinds ofseed in different ears on the same plant and different spikelets in the same ear.(4)It wasidentified that the black point of wheat seed was induced mainly by Alternaria alternata.The wheat seeds were infected by the fungus 25—30 days after flowering.