OBSERVATIONS ON CHYTRIDIACEOUS PARASITES OF PHANEROGAMS. XI. A PHYSODERMA ON AGROPYRON REPENS

Sparrow , Frederick K. (U. Michigan, Ann Arbor), Joyce E. Griffin , and Robert M. Johns . Observations on chytridiaceous parasites of phanerogams. XI. A Physoderma on Agropyron repens. Amer. Jour. Bot. 48(9): 850–858. Illus. 1961.—A Physoderma has been found in Michigan on Agropyron repens, which produces dark-brown, non-erumpent streaks up to 20 mm (usually 4–6 mm) in length by 0.5 mm in width and very local discoloration of the leaf blades and sheaths. There is no systemic infection, and plants parasitized are normal in size and bear flowers. Resting spores upon germination produce zoospores which may develop either into the endobiotic, poly-centric, resting spore-bearing thallus or into monocentric, epibiotic, ephemeral sporangia. The latter bear either colorless or orange globuled zoospores. These zoospores may give rise to new epibiotic sporangia, or, apparently without fusing in pairs, to the endobiotic system. Comparison with other congeneric fungi reported on Agropyron repens reveals the Michigan fungus to be distinct from them. Whether it can be embraced within Physoderma graminis (Büsgen) de Wild. or other described taxa on grasses awaits the results of future cross-inoculation studies.     

关于阿拉善黄芩

阿拉善黄芩与甘肃黄芩应为同一种,其合法学名为Ｓｃｕｔｅｌｌａｒｉａ ｒｅｈｄｅｒｉａｎａ Ｄｉｅｌｓ。     

ON THE GENUS PTERNISTIS.

The Bare-throated Francolins formerly placed in the genus Ptermistis are considered to be members of the genus Francolinus (little adjustment of nomenclature is needed). Their relationship to Francolinus in environment is considered. The systematics of F. afer are discussed and attention is drawn to the genetic features of its hybrid populations.