10 Bacterial Disease of the Mango 



solution ; 54 % on those sprayed with Bordeaux mixture and 67 % on 

 the control trees. 



A second spraying experiment was carried out during the season 

 1912 — 13, but unfortunately weather conditions were again unfavour- 

 able. 



The spraying was done in the orchard described above, trees Nos. 3, 

 5 and 7 in each row being left as controls and the remainder being 

 sprayed with Hycol in the proportion of half a pint to 40 gallons of 

 water (1 in 600). The trees were sprayed four times, and at the time 

 for the first and second sprayings the ground was disinfected with 

 Hycol in the proportion of half a pint of Hycol to 20 gallons of water 

 (1 in 300). 



The season was an exceptionally dry one, the fruit developing slowly, 

 and some trees failing to set any fruit at all. 



Owing to the drought, the disease spread very slowly early in the 

 season ; the first infections on the fruit being observed early in Decem- 

 ber. The trees were sprayed for the fourth time on the 4th December 

 and on this occasion it was computed that -45 % of the fruit on the 

 sprayed trees was infected and 1-2 % of that on the unsprayed.^ 



In January the experiment was discontinued owing to the fact that 

 the fruit had been severely cut up by a hailstorm on the 20th of December. 

 On the 7th of January it was calculated that the unsprayed trees had 

 dropped 36-1 % of their fruit and the sprayed trees 38-8 % since the 

 previous examination. Of the fruit which remained on the tree there 

 was 16-7 % of the fruit on the unsprayed trees diseased as compared 

 with 7-3 % on the sprayed trees. The latter seemed to have made 

 more growth than the former, and the Hycol had not damaged the 

 fruit or foliage in any way. The trees which were sprayed with iron 

 sulphide solution during the previous season had received a severe 

 check. 



The results of this experiment as far as they went were more en- 

 couraging than those of the previous one, but owing to their having been 

 brought to such a premature end they were not sufficiently conclusive, 

 and a further test was necessary. A table is appended showing the 

 rainfall, temperature, etc., during the season. 



The spraying with Hycol was continued during the season 1913 — 14. 

 The first spraying was done on the 29th August, when the trees and the 

 soil underneath them were thoroughly drenched with Hycol 1*600. 

 The trees were then in flower. 



