DISEASES OF CEREALS. 47 



OATS. 



Crown-rust (Puccinia coronata Cda.). — Rust on oats (Avena sativa 

 L.) was not uncommon, but most of our field work was completed 

 after harvest time. Collected from a single locality. 



Specimen collected : San Antonio, 1389. 



Stem-rust {Puccinia graminis P. var. avenae Eriks. and Henn.). — 

 Also collected in a single locality. 

 Specimen collected: San Antonio, 1359. 



Smut (Ustilago avenae (P.) Jens.). — The loose smut of oats is not 

 uncommon in this territory. Extensive loss has been reported from 

 some sections. Fields were observed with 10 to 15 per cent of the 

 heads destroyed. Inquiry revealed the fact that seed treatment is not 

 practiced to any great extent. 



Specimens collected : Austin, 1001, 3117 ; San Antonio, 1358 ; San Marcos, 974. 



RYE. 



Leaf -rust (Puccinia rubigo-vera (DC.) Wint. var. secalis Carl.). — 

 Rye (Secale cereale L.) is not generally grown in this region. Leaf- 

 rust was abundant on plats at the San Antonio Experiment Farm in 

 1908 and 1909. 1 



WHEAT. 



Floret sterility (Stemphylium tritici Patterson). — This disease was 

 found abundantly in 1909 on the leaves and sterile spikelets of wheat 

 (Triticum aestivum L.) near San Antonio. It is closely associated 

 with rusts in causing floret sterility of wheats. 1 



Leaf -rust (Puccinia rubigo-vera (DC.) Wint. var. tritici Carl.). — 

 This rust is abundant on wheat almost every year in the locality of 

 San Antonio and was especially prevalent in 1908 and 1909. 1 



Leaf -spot (Cladosporium graminum Cda.). — This causes brown to 

 black spots on the leaves of wheat and is often found in sterile florets. 

 It was abundant in the San Antonio region in 1908 and 1909. 1 



Loose smut (Ustilago tritici (P.) Jens.). — The dusty olive-brown 

 spore masses appear on the heads or spikelets, destroying them en- 

 tirely and leaving only the naked rachis. 



Specimen collected: Austin, 3115. 



Stem-rust (Puccinia graminis P. var. tritici Eriks. and Henn.). — 

 Wheat is not extensively grown in this section, but the rust was 

 found abundantly present on it wherever it was grown. 



Specimens collected: San Antonio, 1366; Kerrville, 1602. 



Stinking smut (Tilletia tritici (Bjerk.) Wint.). — Found sparingly 

 near San Antonio in 1909. 1 



1 Notes from E. C. Johnson, Bureau of Plant Industry, U. S. Dept. of Agriculture. 

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