384 



Soil Factors on Disease Resistance 



a great loss of sugar. This disease is also important in other parts of 

 India, such as North Bihar, the Godavery delta in Madras, where soil- 

 aeration difficulties are common. Some interesting results have been 

 obtained by Clouston 1 in the Central Provinces on the effect of the 

 physical texture of the soil on the resistance of the sugar-cane to this 

 fungus. On the stiff black soils, in this track, red rot is common; on the 

 neighbouring open porous bhata soils, however, crops as high as 40 tons 

 of stripped cane to the acre are grown and there is a remarkable absence 



Fig. 5. Linseed from Central India (left) and the Indo-Gangetic alluvium (right). 



of the red rot fungus. There appears to be here a case well worthy of 

 more detailed investigation. Soil-aeration and healthy root-development 

 confer a high degree of immunity on the sugar-cane, while the poor 

 physical texture of the black soils appears to render this crop exceedingly 

 susceptible to red rot. The sugar-cane readily lends itself to the investiga- 

 tion of its root-system and of its juices, as the plant is large and abundant 

 material for research is readily available at many centres. 



The protection of fruit trees from green-fly. The usual method of con- 



1 Agr. Journ. of India, Special Indian Science Congress Number, 1918, p. 89. 



