马齿苋叉梗孢一中国新记录

<正>Dichotomophthora was erected by Mehrlich & Fitzpatrick in 1935. Its distinctive characteristics are regularly dichotomously branched or lobed at the apex of conidiophores and brown,

The finding of Dichotomophthora portulacae in China

Dichotomophthora was erected by Mehrlich & Fitzpatrick in 1935.Its distinctive characteristics are regularly dichotomously branched or lobed at the apex of conidiophores and brown,elongate-ovoid to oblong conidia.Dichotomophthora is somewhat similar to Dichotomophthoropsis,but differs in having elongate-ovoid and straight conidia,presenting a striking contrast to helicoid or clavate conidia of the latter.The genus included two species,D.lutea(Routien)de Hoog & Oorschot and D.portulacae Mehrlich & Fitzpatrick ex M.B.Ellis.D.lutea was first described as Dactylaria lutea by Routien in 1957 and then moved to Dichotomophthora by de Hoog & Oorschot in 1983according to dichotomously branched conidiophores.There was additional species named D.indica Rao characterised by unbranched,rarely once dichotomously branched or forked,short,stout,lobed phialides borne on longer and stouter conidiophores,but it was not accepted by many mycologists and treated as synonym of D.lutea.D.portulacae was the pathogen which caused stem and leaf disease of Portulaca oleracea Linn.(Mehrlich & Fitzpatrick 1935; Klisiewicz et al.1983; Mitchell1986; Eken 2003)and was being tested in tomato and pepper crops in Florida for its ability to manage common purslane(Klisiewicz 1985).During a general survey of endophytic microfungi from Basella rubra Linn.at Chengyang district,Qingdao,Shandong province of China,D.portulacae was isolated from leaves of the plant for the first time in August 2006 and 2007.Isolates of the species studied were deposited in Mycology Herbarium at Qingdao Agricultural University(MHQAU).