48 Piirasitism and hnnmmty. 



by inoculating the seed from which they were grown, then a large proportion 

 of the plants which might otherwise have produced bunt-liable varieties would 

 be culled out, and a higher average of bunt-resistance would be secured in those 

 retained. And if the next generation was also similarly infected, further cull- 

 ing-out could be made and a still higher average of bunt-resistance secured in 

 the remaining plants. 



In 1901. experiments were begun in inoculating with bunt the seed which 

 produces the variable generation of new crosses, and in reporting on these 

 Farrer? remarks : — " A large number of experiments were made in sowing 

 bunt-infected seed of unfixed and partially fixed crossbreds, with the object 

 of seeing into the possibility of making varieties which are valuable on account 

 of the resistance they offer to the infection of bunt. No good purpose would 

 be served by describing these experiments in detail. The results, however, 

 from sowing seeds produced by plants of the variable generation which were 

 free from bunt in 1901 are exceedingly encouraging, but it remains to be seen 

 Avhether and to what extent these good results are due to the exceptional 

 character of the season." And in his report for 1903^" he states : — "Whether 

 bunt-proof varieties will ever be secured is, of course, as yet uncertain ; but 

 I have on hand some neAver crossbreds which promise to yield varieties which 

 are better resisters of this parasite than are any of the first batch." And in 

 1905^^ he writes : — " The investigation, however, is very laborious and will 

 take a longer time than I am likely to live. That I am now in a position, 

 however, to select bunt-resisters as parents for crosses is in the direction of 

 helping matters on. Crosses for the special purpose of securing bunt-resis- 

 tance were made this last season (1904) for the first time." 



The lamented death of Farrer, on ITth April, 1906, deprived us of the benefit 

 01 his scientific skill and ripe experience, but Sutton- has brought to fruition 

 the experiments which he initiated. The result is that he has succeeded in 

 producing varieties which apparently resist bunt, for he writes as follows in 

 the Agricultural Gazette of New South Wales for March, 1908 : — "Florence 

 and Genoa have, in our trial plots, shown themselves, under severe trial, to 

 be practically smut-proof, and in consequence, seed of them does not require 

 to be blue-stoned or treated with any other fungicide for the prevention of 

 smut." Florence and Genoa are the result of the same crosses, the parents 

 being White Naples, Improved Fife, Hornblende, and an Indian wheat. Al- 

 though only different strains of the same breed, they vary in the period of ripen- 

 ing, Florence being very early and Genoa about a fortnight later. Genoa also 

 stools much more freely than the other with us. The method followed was to 

 inoculate as thoroughly as possible the seed of each generation of the cross and 

 in tliis way to arrive at the most bunt-resistalit. " Florence and Genoa have 

 proved themselves to be over 99 per cent, smut-resistant, that is to say, that 

 out of 100 seeds thoroughly infected, ninety-nine plants have been found to 

 be entirely free from smut at harvest time." That is certainly a very good 

 record and justifies the hope that the treatment of the seed for the prevention 

 of smut may yet prove unnecessary; but in order to command full price, the 

 wheat must be, as near as possible, bunt-free. In order to get an idea of what 

 the trade required, I communicated with one of the largest dealers in wheat, 

 and received the following reply : — " When selling wheat, we do not allow any 

 percentage for smut. It entirely depends on the condition of the wheat ; if 

 the smut balls are not broken and the wheat not much contaminated, it will 

 probably be about Id. per bushel under prime wheat ; but if the balls are 

 broken and the Avheat badly smutted, the difference is often from 6d. to 9d. 

 per bushel." If the market rates are taken as a guide, there may be from 

 6d. to Is. deducted per bushel on account of smut. When good milling wheat 



