Pes^s and Diseases of Barley. 



The insert pests ol barley arc common to other cereals ard are reft rn 

 in connection with maize. (See page 429.) 



Covered Smut {Unlilago Lor <hi (Pers/ Kell and Sw.). 



This smut is si called because the smul mass recurs in place of grain it. 

 the In ';uls of barley, but remains cos net I by a membrane somewhal resembling 

 that found in Bunt of wheat. The disease is spread by the breaking of 

 the smut balls Mid the spread of the spores to healthy seeds. Smutted 

 heads may he threshed with clean cues and in this way the clean seed 

 becomes infected, t he spores adhering to the outside of the seed aI , ( i resulting 

 in infection of the barley seedling. Soil infection may also occur. 



The bluestone and lime treatment as described for wheat (page 336) will 

 In- effective for Skinless harley.s. 



Other barleys should he treated by thoroughly sprinkling a heap of the 

 seed with a I per cent, formalin solution and covering the wet heap 

 with a bag for four to six hours to allow the vapour of the formalin 

 to penetrate the mass. Sowing should then be carried out soon after tieat- 

 inent in a moist, well-prepared seed bed. Where formalin is used see< 

 should lie obtained from clean crops where practicable, and sowing should 

 not he made in land infected by the smut. 



Bailey should lie grown in a rotation with other crop;. 



Loose or Flying Smut (Ustilago nwla (Pers.) Kell and Sw.). 



This smut can be readily distinguished from the Covered Smut by the 

 appearance of the heads. The smut heads are ruptured fairly early and the 

 spores are blown by the wind on to the flow ei s of healthy plants. There 

 they infect the seed and the embryo within it. Such seed when sown 

 produces smutted plants. 



Fungicide treatments of the seed are unsatisfactory. The most practicable 

 method of avoiding the smut is to select seed from crops that are disease 

 free. This can be most effectively accomplished by growing a seed plot for 

 the production of smut-frte seed for the main crop. If seed treatment is to 

 be used the hot water treatment described under Loose Smut of Wheat 

 •(page 338) will be found effective. The temperature used should be 

 52 deg. Cent. (126 6 deg. Fah.) and the time of immersion fifteen minutes. 

 It is to be noted that the temperature is slightly lower and the time of 

 immersion longer than for wheat. 



Foot-rot (Helminthospi Hum). 



This disease is known to affect barley as well as wheat. The use of an 

 absolutely clean fallow period is recommended (See page 349;. 



A species of Hehninthosporium is also known which cause- Barley Leaf 

 Stripe. This disease is best dealt with by the use of a resistant rarietj 

 by dean fallowing. It is usually only serious in very wet seasons. 



Other Diseases. 



Take-all, Black Stem Rust, Ergot, and Mildew, which are discussed at 

 length as diseases of wheat, arc also diseases of barley. 



