荸荠枯萎病病原菌及其生物学研究

BIOLOGICAL CHARACTERISTICS OF THE PATHOGENIC FUNGI OF WATER CHESTNUT WILT

于1995～1997年从广州南海市采集荸荠枯萎标本,经分离、纯化、鉴定和致病性测定,证实其病原为尖孢镰刀菌(Fusarium oxysporum Schl.)的荸荠专化型。寄主范围测定结果表明,被接种的16种植物中仅有荸荠发病。该病菌分生孢子萌发的温度范围为8～36℃。最适温度28～30℃。菌丝生长的温度范围为8～34℃,最适温度26～28℃。分生孢子萌发的pH值范围为3～10,最适pH为5～7。菌丝生长的pH值范围为3～10,最适pH为6。分生孢子在无菌水中萌发率较低,加入蔗糖或荸荠球茎汁液后萌发率增高。

The pathogen of wilt disease of water chestnut was identified as Fusarium oxysporum f. sp. eleocharidis according to its morphology, cultural character and pathogenicity. This pathogen only attacked water chestnut among 16 species of plants in 8 families tested by methods of impregnated inoculation. The range of temperature for germination was 8- 36 C , with an optimumof 28 - 30 C. The range of pH for conidial germination was 3-10,while the optimum was pH5-7. The range of temperature for hyphae growth was 8-34 C , with an optimum of 26 -28 C. The range of pH for hy-phae growth was 3-10,while the optimum was pH6.