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THE FARMERS HANDBOOK. 



stage serves no useful purpose in the life-history of the Rust in Australia, 

 seeing that barberries are practically unknown here. It is simply a survival 

 stage of the life-history now useless in the Rust's economy. 



Various remedies have been suggested for Rust in wheat, but none have 

 proved entirely efficacious. Wheat which has in any way been checked — as 

 by a dry spell at the early growing period — is particularly liable to suffer. 

 Often wheat grown upon land previously irrigated, or upon well fallowed 

 land, is only slightly attacked — perhaps because of its increased vigour. 

 Burning stubble, rotation of crops, manures, and pickling the seed have all 

 been tried without any markedly good results. A light rainfall, absence 



Fig. 12. — A single sorus of teleutospores of Puccinia graminis. 



Note the two-celled spores, and on the left the epidermis which has been ruptured by the 

 development of the spores. 



of muggy weather, and a crop that ripens early, all tend to produce wheat 

 free from Rust. Protracted moist weather and high humidity during the 

 growing season generally result in a serious epidemic. 



By judicious selection and cross-breeding, wheats have been produced 

 that are more or less rust- resistant, and it is by progress in this direction 

 that the greatest hope of freedom from the rust pest is to be entertained. 

 Experiments in this direction have been and are being continually carried 

 out by the Department, and a number of "Rust-escaping" wheats are to be 

 obtained in Australia to-day, but it is to be noted that none of them are 

 absolutely Rust- resistant. 



