410 Agricultural Journal of Victoria. 



TAKE-ALL AND WHITE-HEADS IN WHEAT. 



(Ophi bolus graniinis, Sncc.) 



Bij D. McAlpine. 



After a long' and disastrous droughty the present season lias been 

 remarkable for a luxuriant growtli whicli lias seldom if ever been 

 equalled, and not only does this apply to fodder and forage crops, 

 but also to the wheat-fields, with their abundant harvest. The 

 favourable season, however, is not without its drawbacks, for it has 

 also encouraged the growth of various fungus parasites, which have 

 tended in some degree to diminish the bumper yield which was 

 naturally expected. 



The rust in some instances did considerable damage, bu.t generally 

 speaking, the crops were too far forward to suffer much from that 

 cause when it appeared. It was mostly confined to the flag, and did 

 not develop to any great extent on the straw, so that the grain was 

 not affected as much as was at first feared. There was a considerable 

 amount of flag smut too in some crops, and they suffered accordingly ; 

 but this disease was not very widespread. Over a large area, how- 

 ever, there were strips and patches in which the wheat-plants seemed 

 to have been arrested in their growth, and in these there were only 

 miserable stunted specimens, dying off at various stages while still in 

 the blade. Such patches have long been known to farmers as take- 

 all, which is a convenient and expressive term to indicate that owing 

 to some cause or other, nothing is left but the withered remains of 

 dead plants. Even in driving past the wheat-fields these gaps in the 

 crop are easily seen, and often fairly numerous. Then as the season 

 advanced, and the ears began to appear, it was found that wheat- 

 plants which promised well, and had fully formed heads, did not 

 develop grain, or if they did, it was shrivelled and almost valueless. 

 The plants were not only dead at the top, but also from the root 

 upward, and the whole had a bleached ap])earance, so that the name 

 of white-heads has been given to this disease, from the striking 

 appearance of the ears as if prematurely ripe. A solitary plant 

 might be seen in the midst of others, with well-tilled ears, or there 

 might be strips and patches of them, just as in the case of take-all. 



Although these two diseases have long been known as destructive 

 to our wheat-crops, and considerably depreciating the yield, still their 

 true nature was not understood, and they puzzled not only the farmer, 

 but even those who had devoted some time to their investigation. 

 Their prevalance this season, and the favourable conditions for their 

 development have enabled me to determine the immediate cause, and 

 it will now be my object to show that take-all and white-heads are 

 both different stages of a diseased condition of the plant, caused by 

 one and the same fungus, which occurs at the base of the stem and 

 on the roots. 



