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THE AGRICULTURAL NEWS. 



(Septembek 26, 1014. 



FUNGUS NOTES. 



SORGHUM SMUT. 



Speriiufii^ cif iiiipht-e rtttaokeJ by a. sliiut ilisease \\eie 

 "J-eceiitly received from ilontsenat, with an enquiiy a.s to 

 treatment. The smut proved to be due to the well-known 

 Sph JLcelotheca (I'stilago) sonihi, (Lk.) Clinton, which is kno\VL\ 

 to occur from time t(i time on imphee and Tininea corn in the 

 AVest Indies. 



The spores of the fungu.s are usually .sown with the seed, 

 germinate in the soil at the .'<ame time, and infect the seed- 

 lings at an early stage. The mycelium of tlie fiuigus keeps 

 pace with the extension of the plant in the form of thin 

 threads which grow up through the softer tissues, especia.lly 

 the pith. No particular damage to the plant is caused and 

 "jio sign of the disease is visible until the period of flowering, . 

 when the fungus develops rapidly in the anthers and ;Ovaries, , 

 and there produces masses of black powdery spores which 

 replace the pollen anfl the seeds. The outward appearence 

 of the panicles is not much altered until the mendu'ane which 

 nt tiist encloses the spore masses bursts, when they appear as 

 if coated with powdery soot. 



The spores are \"ery resistant, and the occurrence of 

 ■■d >niall (piantity of smutted material among the seed corn is 

 capable of producing widespread infection in the following 

 crop. The disease is thus cumulative, and its occurrence even 

 in small proportion,-, should therefore nnt be considered 

 Jiegligible. 



Treatment is rendered eas)' by the absence of the fungus 

 hijw the interior of the seed, and owing to the fact that only 

 very young plants can be infected. Any method which 

 secures the sterilisation of the seed without destroying its 

 germinative power is eflective. 



Two types of treatment are in comnmn use against this 

 and other diseases of a similar nature, depending on the use of 

 (1) chemical fungicides, (2) hot water, for the killing of the 

 spores. The hf)t water process is a somewhat delicate one, 

 since a temperature of at least 129° F. has to be maintained 

 in order to secure the desired ert'ect, and a temperature above 

 138°F. is liable to kill the seed. This involves an equipment 

 and a carefulness in handling that are not always at the 

 service of the West Indian planter. The use of chemical 

 fungicides is more likely to meet his case. 



The sul)Stances most in favour for the purpose are 

 (1) formalin and (2) copper sulphate. Dilute .solutions of 

 either substance may be u.seil in two ways. The seed is 

 either steeped in the solution or is sprinkled with it and then 

 thoroughly mixed in order to secure uniformity of action. 

 Commercial foimalin is a 10-per cent, solution of fornial- 

 flehyde gas in water. It is not dangerous to use, but its 

 fumes have a strongly irritant action on the mucous mem- 

 liranes of eyes, nose, and throat, and even weak solutions 

 cau.se a haishness and peeling of the skin if allowed to 

 lemain in contact with it for any considerable time. A solu- 

 tion of proper strength Ls obtained by nnxing 1 pint of 

 formalin with 30 gallons of water. The cost of formalin 

 in Barliados is 3.s. per (Imperial) pint. If copper sulphate 

 (bluestone) is used, 1 Iti. should be dissfilved in 10 gallons 

 of water. 



In carrying out the steeping method, the seed is con- 

 tained in a bag or close basket and immersed in the solution, 

 being lifted up and down a few times to get rid of the 

 enclosed air. The time of soaking is two hours in the case 

 of formalin, thiee minutes in the case of copper sulphate 

 solution. 



In the .sprinkling method, if formalin is u.sed, the grain,, 

 after it has become thoroughly wet should be left iji 

 a covered wooden vessel, or in a heap covered with wet sac k- 

 ing. for several hr)urs, and then spread out to dry. If co|)per 

 sulphate solution is used, the grain shoTild be dried ininicdi- 

 ately. 



It is advisable to test the germination of the treated 

 .■-eed before sowing, .so that allowance may be made for any 

 which has been killed. Formalin is less likely tu damage the 

 .>eed than copj)er sulphate solution. 



In handling the grain after treatment, the greatest care 

 .should be taken that it d<ies not come iirto contact with any 

 article that is likely to be contaminated with smut s[)ores, 

 and that it is not expo.sed where ilust which may contain the 

 spores is likely tfi settle upon it. 



There is another .sorghum smut, Sphacelotheca (I'stilago) 

 reiliana, (Kiihn) CI., which differs from the above in that, 

 instead of the grains being affected separately, the whole 

 head is conglomerated into a smutted mass. 



This does not appear to have been recorded from the 

 Lesser Antilles. It is not amenable to the treatment describ- 

 ed above, but mu~t bf met by obtaining seed from an unin- 

 fected source. 



DOWN THE ISLANDS. 



ITEMS OF LOCAL INTEREST. 



i;i:esai«a. The Land Officer's Report for August states 

 that work on the Settlement roads at St. Cyr was continued 

 this month. As regards progress of work on the holdings in 

 general, the allottees on all the Settlements were engaged 

 during the early part of the month in weeding corn and 

 sugar-cane. During the latter part of the month, they were 

 occupied in preparing land for planting cassava and sweet 

 potatoes. Turning to the condition of the crops, the Land 

 ( )tficer reports as follows: 'Maize shows considerable promi.se, 

 the weather having been very favourable for its growth. 

 Larger areas than last jear having been planted the crop 

 should be a liig one. As regards sugar-cane, this crop ha.s 

 also benefited by favourable weather and is now very proniis- 

 ing. The areas on all Settlements have been extended this 

 year. In connexion with ground provisions, those already 

 planted are doing well. The cassava crop at Westerhall 

 is satisfactory, and fairly large reapings should be made 

 during the coming months. Fair quantities of peas have 

 been reaped, and mo.st of the .settlers are being induced 

 to re-plant further crops of this quick food-producing 

 product as soon as one crop is reaped. The root crops, 

 such as yams and tannias, are lieing gradually jnit in and are 

 doingwell.' 



ST. LUCIA. On the Land Settlement at Reunion .several 

 allotments are now occupied and bear crops that are in 

 excellent condition. The Government has offered lots free 

 for the period of one crop for the cultivation of provisions. 



Work in the Experiment Stations has included the 

 distribution and transplanting of limes and the plant- 

 ing of wind-belts. Observations relating to the staple crops 

 show that cacao promises well whilst the prospects tor sugar 

 are exceedingly good. The second lime crop was coming in 

 at the time of writing. 



