124 MOSAIC DISEASE 



Cross inoculations have been carried on with these two 

 organisms and their identity definitely established. This 

 means that if your Sweet Peas grow near some Apple 

 orchard, and if the latter suffers from the bitter-rot, it 

 will be carried readily by the wind or some insect to the 

 Sweet Peas and produce anthracnose. It is thus seen how 

 serious a proposition this becomes when we consider the 

 many hosts which can communicate this disease. 



" The symptoms of the anthracnose of the Sweet Pea 

 are diverse. Sometimes the disease is manifested in a 

 wilting and dying of the tips. These diseased parts become 

 whitish and brittle and soon break off. Sometimes the 

 dying works downward, and this involves the entire branch. 

 Oftentimes the leaves are attacked and they soon die. On 

 the leaves the disease starts as a white spot, which enlarges 

 and involves the entire area. On the blossoms the fungus 

 either attacks the junction between the flower buds and the 

 peduncle — in this case the bud drops off, leaving the 

 peduncle intact — or it attacks both flower bud and peduncle, 

 and this time both dry up but do not fall off. The seed 

 pods are also attacked in all their stages of development; 

 in this case the fungus works inward until it reaches the 

 seeds. The fungus is capable of living over Winter on 

 diseased parts of the plants, in the soil or on the seeds, as 

 was definitely proved in our experiments." — (Taubenhaus.) 



The third annoying trouble is what is called the Mosaic 

 disease, which may be recognized by the yellow dotting or 

 mottling of the leaf, presenting in some instances a beauti- 

 ful mosaic structure. This disease makes its appearance 

 after the seedlings are from three to four weeks old and in 

 bad attacks it curls up the leaves and dwarfs the plants. 

 Sometimes, by judicious management as to watering, 

 temperature and feeding, the affected plants outgrow the 



