Journal of Agriculture. [lo April, 1909. 



At Burnley T. tritici was also used for infection, but no conclusions as 

 to their relative virulence could be drawn from a single season's experiments. 

 In the two plots of Florence and Genoa respectively inoculated with spore> 

 of T. tritici the average was 4.16 and 15.68 per cent. 



At Dookie, the Principal tested the effect of re-smutting some of the 

 grain already sent with similar sj)ores. 100 .smut-balls were powdered 

 and then made into a soft paste with the addition of water; 100 grains 

 were placed in this paste, thus allowing one smut ball on an average fox 

 each grain, mixed thoroughly and allowed to soak over night. Bv next 

 morning the moisture had disappeared and the seed was sown the same 

 day. Infection in the xe-smutted grains was the most virulent, for while 

 it \ ielded 5.72 and 9.79 per cent, of Inmt respectively in Florence and 

 Genoa, there was only 2.42 and 2 per cent, respectivelv with the ordinary 

 dusting of the grain. 



It is clear from these experiments that Florence and Genoa do not 

 possess the hereditary quality of bunt-resistance, and Sutton evidently 

 suspected this as he wrote to me as follows in May, 1908 : — 



I have been referring to the results of our tests with these wheats while ihey 

 were being fixed, and I find that in 1905 they were at Lambrigg fairly bunty, and 

 this may indicate that they are not constitutionally resistant to bunt, but they 

 escape bunt through some peculiar characteristic of their growth immediately after 

 germination. 



Rapidity of germination is found to be associated with resistance to 

 bunt, and the.se two varieties are found to be relatively xapid in their 

 germination. But in order to secure complete immunity and the hereditary 

 quality of resistance, it will be necessary to breed from a variety which has 

 shown itself to be free, when expo.sed to the most severe infection for a 

 series of sea.sons. 



Dookie Experiments. — Mr. Pye, Principal of Dookie Agricultural 

 College, had been working for a number of vears in conjunction with Mr. 

 Farrer in endeavouring to produce bunt-resisting wheats by selection after 

 seed-infection. He is still continuing this work and the most promising 

 line lies in breeding from crosses of the Durum variety that resist the bunt. 

 He found for instance that Medeah is not so liable to bunt as many others, 

 and he is using this variety as a parent. The seed of the progeny is 

 then dusted with bunt spores, and the seed from those plants which escape 

 infection is sown next season and so on until a strain is secured which 

 will be bunt-resisting. Among the numerous varieties grown there were 

 several which promised to he more or less bunt-resisting, and the.se were 

 u.sed as parents for further crosses, but the onlv one found to be absolutelv 

 free during the past .sea.son, after thorough infection of the seed, was 



Medeah 



Tripola 



and TT-*! "^1 'T-iid these will be tested in a similar fashion to Florence and 

 Genoa. The smut experiments carried out at Dookie were on a most com- 

 prehensive .scale, as during the past season there were over 200 plots 

 devoted to smuts aiont'. In addition to those alreadv enumerated, thev 

 included .seed treatment with a great vaxietv of substances and the effect of 

 planting smut-balls close to seed. 



ITT. — Experiments witit Flag Smut. 



This is a di.sease which is widelv distributed in the northern areas of 

 Victoria and in some seasons reduces tiie crop considerablv. The spores- 



