INSTITUTE AND COLLEGE, PUSA, FOR 1913-14. 41 



seed, the indigo can be cut back and good crops of leaf taken 

 the following monsoon. 



Attention has also been paid to the method of pollina- 

 tion in Java indigo, from the point of view both of seed 

 growing and of improving the plant in indican produc- 

 tion. Pollination by bees is the rule and very few seeds are 

 produced by covered plants. As would be expected from 

 the method of pollination, the progeny of single plants 

 showed that natural crossing is common. These facts 

 indicate that ordinary single plant selection methods in 

 Java indigo are not likely to yield results at all commen- 

 surate with the work which this method would involve. 

 Some system of mass selection, in which undesirable forms 

 are eliminated prior to flowering, seems much more likely 

 to lead to improvement. Advantage will have to be taken 

 of those individuals in the mixed crop which grow rapidly 

 and strongly and which by their habit of growth and 

 amount of leaf surface are likely to give the highest yields 

 of green leaf. These will have to be grown separately, away 

 from other indigo, and a process of rogueing carried out 

 before flowering time so that all undesirable types are 

 weeded out and not allowed to cross with the rest. The 

 fact that bees are necessary for the pollination of Java 

 indigo indicates that for seed purposes the plants should be 

 properly spaced and not grown too close together. Copious 

 setting is obtained if the crop is grown in lines about two 

 feet apart. Cultivated in this way, Java indigo branches 

 freely from the ground and there is ample room for the 

 bees. 



During the progress of the indigo investigations it 

 became evident that one important method of improvement 

 had been, to a large extent, neglected. In the past, it has 

 been tacitly assumed that the methods of cultivation in 

 vogue in Bihar are more or less perfect and that any line 

 of advance must necessarily begin in the laboratory. The 

 results obtained at Pusa have shown that a considerable 

 degree of improvement is easily possible in the actual grow- 



