W. J. DowsoN 99 



No. 11 is a selection from the hybrid "Early Rieti" and "Red Fife," and 

 has proved highly resistant to Puccinia graminis in all parts of the 

 country so far tried. The other resulted from the cross " Egyptian No. 3 " 

 and " Nut Cut." " Egyptian No. 3 " by itself was found to be very resist- 

 ant to Puccinia graminis but susceptible to Puccinia glumarum, while 

 the Australian "Nut Cut" was susceptible to Puccinia graminis but 

 resistant to Puccinia glumarum. From the resulting hybrid Cross No. 13 

 was selected and was found highly resistant to both rusts, 



VIII. Flax. 



Flax, which grows well in the Highlands, is subject to the attacks of 

 numerous enemies, chief of which at the present time is the cut worm, 

 the larva of certain moths. The loss caused by the depredations of this 

 grub are enormous, whole fields being completely destroyed soon after 

 the plants appear above the ground. Any spray which poisons the cut 

 worms also kills the flax, and up to the present no method has been 

 devised of coping with this most destructive pest. As has been noted, 

 newly planted coffee is also very subject to the attentions of these larvae, 

 but in some districts the pest is more prevalent than in others. 



The mature flax plant is often attacked by a flax moth which lays 

 its eggs in the ripening capsules so that considerable damage is caused 

 in this way to flax grown for seed. 



Of fungous diseases, the wilt caused by Fusarium lini Boll, is the 

 most important and is commencing to spread in certain localities. The 

 appearance of this disease is most probably due to imported seed bearing 

 the conidia of the Fusarium, and its spread is undoubtedly the result of 

 the present practice of growing two or even three crops on the same land 

 without a break or rotation. Experiments designed to prevent the spread 

 of the wilt by infected seed have been commenced, and although of a 

 preliminary nature, have given unexpected results. As flax seed is 

 extremely difficult to disinfect by the usual method of wetting with 

 formalin solution, or with copper sulphate, by reason of its mucilaginous 

 coat, it was thought possible that the desired result might be obtained 

 by subjecting the seed to the action of formalin vapour. The first experi- 

 ments were designed to find out what effect the action of the gas would 

 have on the germinating power of the seed. Fresh seed from an unin- 

 fected area was treated for 4 hours, and the amount of formalin or the 

 number of tablets was to be increased steadily until a marked effect on 

 the germination of the seed was produced. After each experiment 

 200 seeds were counted out and placed in petri dishes to germinate. The 



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