苎麻疫霉雄器侧生性状的遗传研究*

在来自江苏、江西棉花、芒麻和构树的12个些麻疫霉（PhytophthoraboehmeriaeSawada）菌株中均观察到侧生雄器，其比率为4．0％～16．5％。在以菌株JS－5和PM－8（雄器侧生比率分别为16．5％和9．5％）为亲本所建立的连续2～3代单游动孢子无性系后代中，雄器侧生性状可以遗传，但单孢株间雄器侧生比率有一定差异，其分布范围分别为9．0％～34．0％和2．5％～15．5％。进一步诱导菌株JS－5的单游动孢子株的卵孢子萌发，分别对具侧生雄器和具围生雄器的藏卵器（卵孢子）进行单孢分离，检测雄器位置性状在由上述不同来源卵孢子萌发所形成的单卵孢株后代的遗传与变异。结果表明，无论是由具侧生雄器的藏卵器中的卵孢子萌发形成的单卵孢株，还是由具围生雄器的藏卵器中卵孢子萌发形成的单卵孢株，其有性器官均具有雄器侧生与雄器围生两种类型，但侧生比率在各代菌株间有很大差异。S1代单卵孢株的雄器侧生比率分布范围为1．0％～79．0％，其中具侧生雄器的藏卵器中卵孢子萌发形成的单卵孢株雄器侧生比率较高（分布范围7．0％～79．0％，平均33．6％），而来自具围生雄器的藏卵器中的卵孢子萌发形成的单卵孢株雄器侧生比率较低（分布范围1．0％～32．0％，平均11．52％）。S2代单卵孢株的雄器侧生比率为10％～9

INHERITANCE OF ANTHERIDIUM ATTACHMENT MODE OF PHYTOPHTHORA BOEHMERIAE

The paragynous Phenomenon (oogonia with paragynous antheridium)and the inheritance of attachment mode of antheridium on oogoniuxn in Phytophthora boehmeriae Sawada were reported in thes paper.In all of the 12 tested wild-type isolates of P.boehmeriae obtained from cotton (Gossypium hirsutUm), ramie (Boehmeria nivea) and papermulbeny (Broussonetiapapyrifera) in Jiangxi and Jiangsu provinces, the paragynous antheridia (PaA) were observed with a Percentage range from 4.0% to 16.5%, which suggested that the paragynous phenomenon was common in the isolates of P.boehmeriae from China.Two selected wild-type isolatos, JS-5 and PM-8 (with percentages of oogonia with Pall being 16.5% and 9.5% respectively) were induced to sporulare and asexual monosporous progenies were established. The character of oogonia with PaA could be inherited in two to three succssive single zoospore generations from the both parents, but the percentage of PaA showed variahon (9.0% to 34.0% for JS-5 and 2.5% to Present address: Department of Plant Protechon, Anhui Agriculed University, Hefei 230036, P. R China )15.5% ror Pads).The oospores of a single--zoospore isolate (with 18.0% of PaA) from the wild--typeisolate JS--5 were induced tO gendnare and single oosPOre culests derived from theoogonia with PaA and from those with amphigynous antheridiuxn (AmA) were isolatedrespechvely. The oogonia with PaA and the ones with AmA were also observed inall of the single oospored cultUres in spite of their origins. However, the Percentagesof oogonia with PaA (PaA Percentage) in the sexual progenies (S,) displayedconsiderable variation, ranging from 1.0% tO 79.0%, and in general, the PaAPercentages in the single--oospore cultures derived from the oogonia with PaA (rangingfrom 7.0% to 79.0%, averagely 33.16%) were higher than those in the single--oosPOrecultUres derived from the oogonia with AmA (ranging from l.0% to 32.6%, averagelyl I .52%).In S, progenies from 4 selected single--oospore cultures (two derived fromoogonia with PaA and another tWo from oogonia with AmA) of S, progeny, the PaAPercentages ranging from l.0% tO 91.0%, with a similar variation tendency tO S,Progenies, but the vatiation ranges were obViously greaser in the S, progenies than inthe asexual progenies which also derived from the four selected single--oosporecultures of S, progeny. It was also observed that the PaA Percentages of monosporousisolates with high PaA proponion, no matter from asexual or sexual progenies, wereunstable and decreased in subcultUres by mass transfers.The above resultS indicated that the character of antheridium ~hment mode ofP. boehmeriae could be inherited but showed variation in both asexual and sexualprogeny, and suggested that the character might be controlled by cytoplasndc factorsand slso associated partly with nuclear faCtors. Based on the resultS the authorssuggest that the charactor of the attaChment mode of oogoula with PaA should besuPPlemented to the species descriphon of p.boehmeriae Sawada.