30 REPORT OF THE AGRICULTURAL RESEARCH INSTITUTE 



proposed to publish from time to time the value of the- 

 annual produce so that this can be compared with the 

 capital involved in the improvement. There is no doubt of 

 the effect of thikra in increasing the value of green-manure. 

 The question that remains for decision is whether the? 

 improvement will pay under present conditions. It is 

 expected that the Dholi results will answer this question. 



Indigo. 



In the last annual report, a detailed account was given 

 of the results of our study of the wilt disease of Java indigo 

 and of the importance of soil-aeration in the development 

 of the roots and root-nodules of this crop. The question of 

 the production, on the Bihar estates, of the seed of Java 

 indigo was also dealt with and the conditions necessary for 

 success were outlined. The general experience of the past 

 indigo season supplied an interesting confirmation of the 

 views put forward in the first and second reports on the- 

 improvement of indigo. The monsoon of 1915 in North 

 Bihar was heavy and well-distributed and, in addition to 

 the rainfall, there occurred a series of floods which on most 

 estates cut short indigo manufacture and killed out large 

 areas of the crop. The weather during the first half of 

 August — the period when Java indigo has to be sown for 

 seed — was very wet and few breaks occurred. The almost 

 continuous rainfall after the seed crop was sown, coming 

 as a re-inforcement to the heavy falls in July and the floods,, 

 so consolidated the soil and interfered with its aeration 

 that on a comparatively few estates only did the seed crop 

 do well. It was only in cases where the surface drainage 

 was good and the natural aeration of the soil was above the- 

 average that Java indigo sown for seed was able to 

 grow normally and produce an average outturn. On the 

 heavier soils in the submontane tract and on the lighter 

 lands which had been flooded previous to sowing, the soil- 

 aeration was so interfered with that the seed crop was 

 attacked by Psylla and proved a complete failure. On some 

 of the drained plots at Pusa, the seed crop was distinctly 



