lf>20] DISEASES^ OF PLANTS. 653 



(liosrorra n. sp. Barterlal bud rot of coconut in the Awka district was broujiht 

 under control durinfr 1917. Roots of Para rubber trees bearins larf:e galls wen? 

 found to be attacked by a parasitic plant, probably Thonniufiui xduijuinca. 



Speciiilizutioii in IVronospora calotheca, E. Gaumann (Svcnsic Hot. Tidnkr., 

 U (lUlX), \n. Jf. pp. 'iSS-Jfio, fios. .?). — Four new Peronosporas are recognized as 

 found on different parts of Galium spp., namely, P. apariiiex, P. horenlis, P. galii 

 rt-ri. and /'. xilratica. 



Seed corn irifectiou with Fusariuni nionilifornie and its relation to the 

 loot and stalk rots, W. D. Vaixeau {Kentucky Sta. Buh 226 (1920), pp. 21-51, 

 fig. 1). — The author presents data regarding the extent of infection of seed corn 

 grown in various parts of Kentucky and several other States, and its possible 

 hearing on the high percentage of root and stalk rot infection found in the 

 Held. 



Field examinations at Lexington have shown infection with the root and 

 stalk rots to an extent of nearly 100 per cent. Studies of considerable numbers 

 of ears of seed corn from a number of States showed infection with F. monili- 

 fomic, and no ears examined from the districts from which the corn wa.s ob- 

 tained were found free from infection. 



The occurrence of pink crowns or stripes on normally white kernels is said to 

 be an indication of infection with F. moniliforme, and the development of red- 

 dish or black discolorations of the seed coats of corn during or after germina- 

 tion is an indication of the presence of the same fungus, while the absence of 

 discoloration is not considered conclusive evidence of freedom from infection. 

 As a result of careful examination of more than 60 ears, the presence of any in- 

 fected grain is believed to indicate that all the kernels are infected. F. monili- 

 forme is said to b(> an active parasite and capable of causing root and stalk 

 rots of corn imder laboratory and field conditions. 



Tlie seed gernunator method of selecting disease-free seed is reported as not 

 j)roving practical with the seed studied as a means of eliminating diseased 

 ears. 



liecause of the high degree of Infection of seed corn with F. moniliforme over 

 much <»f the corn belt, it is considered probably the most common cause of root 

 and stalk rots of corn. The author claims that Gihherclla sp. may or may not 

 be present in a ti^-ld badly infected with the root and stalk rots. F. moniliforme 

 Is said to be the more active parasite when it and Qibberella sp. are associated 

 on rotting stalks of corn. 



Biologic forms of Puccinia coronata on oats, G. R. Hoerner (Phytopa- 

 lliolofnj, 9 (linU). A'o. 8. pp. S09-SV,, pis. 2).— In a study of the infection capa- 

 bilities of /'. coronata, the author inoculated 55 species of cereals and grasses 

 with rust cidtures obtained from oats in four widely separated States. The 

 behavior of the oat plants suggested the possibility of biologic forms of the 

 crown rust, and further inoculation experiments were undertaken using rust 

 jiialerial from .'Wt different localities. Judging from the behavior of the varieties 

 of oats, the author concludes that there are at least four biologic strains of the 

 crown rust. The results of his experiments are considered significant, as they 

 may throw some light on epidemiologj' studies and perhaps materially affect 

 the problem of breeding oat varieties for resi.stance to crown rust. 



Relation of tlu' barberry to stem rust in Iowa, I. E. Meihts. L. W. Dxtr- 

 RELL, and R. S. Kiuitv (lova F^ta. UcHairch liul. .57 (1920), pp. 283-82',, fipa. 

 il)- — The authors give accounts of data and ob.servations on the manner of in- 

 fection of the alternate host, the sii.<;ceptibility of the yomig and older leaves 

 and different varieties and species of the genus Berberis, the incubation period, 

 and the influence of climatic factors on .-ecldiospore production of Puccinia 

 graminis. 



