Vol. IX. No. 211. 



THE AGRICULTURAL NEWS. 



167 



The probable connexion of this ili-^ease with angular 

 leaf spot is important, as practicall} no Held of cotton is free 

 from the hitter, and it is reasonable to assume that infection 

 is mainly spread by broken pieces of diseased leaves that 

 contained the bacteria and are carried by the wind to healthy 

 parts of other plants. In this case, the best remedy probably 

 lies in destroying all old cotton as early as is feasible, so as to 

 give the longet-c possible interval between two successive 

 plantings of cotton on the same land. 



Fungal hyi>hae have occasionally beejj found in these 

 areas in both forms of the di.sea.se: but as they are not 

 always present, it is reasonable to assume that they are only 

 of a saprophytic nature and that the bacteria are the real 

 cause. This is further supported by the fact that there were 

 indications that the mycelium belonge<l to a species of 

 Fusai-iuin, several of which are known to be saprojihytic on 

 diseased portions of the cotton plant. 



In the supplement to the Xyasaland Government 

 GazetU for February 28, 1910, an account is given by 

 J. S. J. McCall of the effects of this disease in that Protecto- 

 rate, where the Egyptian variety of cotton has lieen so 

 severely damaged as tf> necessitate its abandonment in 

 .some districts. It was found there that the cotton 

 was more prone to attack when growing in wet low- 

 lying hollows, and that it was more profitable to plant in 

 March or .\pril at the end of the rainy sea.-nn than in Novem- 

 ber or December at its commencement; although the crop 

 sown in .March or April does noi. cmisi-st of such large 

 plants as one put in the commencement of the rainy 

 season, it was much less prone to attack by bacterial 

 blight. The writer lays much emphasis on the speedy 

 destruction of the old plants as soon as the crop has been 

 removed, and also calls attention to the fact that care should 

 be taken to avoid using seed for planting purposes from 

 a plantation already infected, and to the advisability of 

 disinfecting all seed. 



Although the di.sease does not assume such .serious pro- 

 portions in the West Indies, yet it is sutliciently prevalent to 

 justify further investigations, and it is proposed during the 

 coming season to institute field experiments with a view to 

 determining the following points : — 



(1) The general prevalence of the di,-;ease. 



(2) The appro.ximate date of the first attack. 



(3) The approximate dates of the period of greatest 



prevalence. 



(4) The stage of the boll at which it is most prone to 



attack. 



(5) The connexion between the two forms of the di.sease. 



(6) The effect "f climate and soil. 



(7) Its relationship, as far as possible, to angular leaf 



spot. 



For this purpose, it is suggested that three or four fields 

 of cotton in each Island, situated on as many difterent 

 types of soil as possible, might be kept under careful 

 observation throughout the coming season. The points 

 to be observed are the date of the first appearance of 

 angular leaf spot and the general weather conditions 

 prevalent at the time, the date of the first appearance 

 of the diseased bolls and the appro.ximate age of such bolls, 

 the general abundance of angular leaf spot and the general 

 conditions of weather throughout the season. Once the 

 disease has made its appearance on the bolls, a few trees 

 might be chosen each month at random in different [larts of 

 each field, and all the bolls from these pickiil. The percent- 

 age of total disea.sed bolls for each field could then be 

 estimated from the percentage of these in Ihose galliered. 



This would give an idea of the prevalence of the disease dar- 

 ing each month. In addition to thi.<, the disea.sed bolls 

 obtained at each picking might be roughly sorted into young, 

 half-giown and full-grown, and the percentage of each in the 

 total number of diseased bolls picked might be recorded. This 

 would show at what stage the bolls were most prone to attack, 

 taking into account the records throughout the whole crop. 



THE COMING COTTON-GROWING 



SEASON. 



A.S the time of planting for the next cotton-growing 

 season will soon have arrived, it is natural that planters 

 .should be .seeking indications that will form a guide in the 

 matter of deciding upon the area to be devoted to this crop. 

 The experience that has been gained in the past in cotton- 

 raising will, in individual cases, go a long way toward 

 giving the information that will assist in arriving at a decision, 

 but this must be supplemented by a knowledge of the pro.s- 

 pects of a good demand for cotton, with reasonable prices. 



Information has been received that, owing to the failure 

 of the Egyptian crop, and to the scarcity of high-class Upland 

 aotton, there has been a considerable increase in price, as 

 regards good staple cotton, relatively to that of the ordinary 

 cotton. That an actual increase has taken place is shown by 

 the lists of prices . obtained throughout the West Indies, 

 published recently in the A;iriciillural Xeios. Such a con- 

 dition leads to the reasonable hope that good prices will 

 be obtained for West Indian cotton, at any rate in the more 

 immediate future. 



There is justification, under these circumstances, for 

 advising that a moderate increase in the area under cotton 

 cultivation in the West Indies should take place. This 

 increase should, however, be made more especially on estates 

 where the cultivation is conducted with great care, and where 

 efforts are made seriously to obtain the best results from it. 

 It should not result from the taking up of cotton-growing by 

 those who have had no experience in this industry, for it is 

 essentially one which requires good practical knowledge and 

 serious care and trouble. This must be realized, as well, by 

 those who have gained an intimate acquaintance with the 

 work which is required for the raising of cotton; otherwise, 

 the best plan would be for them to abandon all ideas of under- 

 taking its cultivation 



Particulars in connexion with the work that will have to 

 be conducted on estates before the seed for the coming crop 

 is sown were recently given on page 86 of the present volume 

 of the A;iriridtural Xeirs, and the necessity for early planting, 

 especially where there are liable to be attacks of the flower- 

 I'ud maggot, was emphasized. Attention may be drawn again 

 to the great importance of the destruction of old cotton plants 

 before the new seed is sown. Every cotton planter should 

 perform his share of this work, not only in his own interest, 

 but in that of all those who are engaged in the industry. It 

 is not sufiicient for this to be done immediately before the 

 seed for the new crop is sown; time should be allowed for 

 such of the pests as have escaped destruction to be removed 

 by natural agencies from the land occupied by the plants on 

 which they were living, for it is conceivable that the disturb- 

 ance entailed by the preparations for burning the old plants 

 will assist in distributing the pests in such a way as to enable 

 them to attack most readily any cotton that is planted soon 

 after this has taken place. It is h<iped that planters will give 

 tliis necessary and important part of the routine in cotton 

 cultivation the thought and attention which it merits. 



