July, 1912.] 



Edible Products. 



average return is from 1,000 to 1,500 lb. 

 of dried ginger per acre, but as much as 

 2,000 lb. per acre has been obtained 

 under the best conditions. The recorded 

 yields in different parts of India vary 

 within wide limits. In Bengal it is 

 stated that 1,000 to 1,500 lb. per acre is 

 the average crop ; in the Punjab 2,100 lb., 

 in Travancore 2,000 to 2,500 lb., whilst 

 in an experimental cultivation at Surat, 

 Bombay Presidency, the yield was equiv- 

 alent to over 8,000 lb. per acre. As 

 already mentioned, a yield equivalent 

 to nearly 3,000 lb. per acre was obtained 

 in Jamaica on exhausted land by the 

 application of a suitable manure; and 

 there is no doubt that, by careful cultiv- 

 ation and manuring, the yield in all the 

 countries mentioned could be consider- 

 ably increased. 



Pests and Diseases. 



Owing to the pungent nature of the 

 shoots, the ginger plant is attacked by 

 very few insect pests, and it has even 

 been recommended that the crop should 

 be planted in orchards to prevent the 

 development of pests of fruit trees. At 

 the Rangpur Agricultural Station, 

 Eastern Bengal, however, the larva of a 

 Drosophelid fly, which lives on coarse 

 grasses, has been observed to do a good 

 deal of harm to the shoots. 



Considerable damage is inflicted on 

 ginger crops in Jamaica and parts of 

 India by a disease which attacks the 

 underground part of the plant, and 

 brings about decay of the rhizomes. 

 The symptoms of the disease are similar 

 in the two countries, but whether or 

 not they are identical is not clear from 

 the published records. The first indi- 

 cation of the disease is a yellowing of 

 the leaves, which droop and wither ; 

 the bases of the stems become discoloured 

 and rot, and finally decay spreads to 

 the rhizomes, which disintegrate to form 

 a putrefying mass of" tissue. In Jamaica, 

 where the disease is called " black rot," 

 a fungus was present in the decomposing 

 rhizomes which formed spores in a 

 similar manner to Allantospora radici- 

 cola, Wakker, a fungus which causes 

 ft root disease of sugar-cane in Java. It 



was not clearly shown, however, that 

 the fungus found in the old rhizome 

 was the cause of the disease, (Howard, 

 Bulletin Botanical Department, Jamaica, 

 1901, 8, 181 ; 1902, 9, 42). A distinct fungus, 

 identified as Pythium gracile, was found 

 in diseased rhizomes in India, and al- 

 though there is some evidence that it is 

 the cause of the disease, this has not 

 been conclusively proved to be the case 

 (McRae Agricultural Journal of India, 

 1911, 6, 189). The disease spreads rapidly 

 through the soil, and to prevent infec- 

 tion of healthy plants every portion of 

 an affected plant must be removed and 

 burnt, whilst the soil itself should be 

 treated with lime, or a light dressing 

 of sulphate of iron may be applied. 

 Isolation of infested soil by trench has 

 been tried with success but in the case 

 of a bad attack ginger should not be 

 grown on the land for at least three 

 years. The disease is most serious on wet, 

 heavy soils, or in exceptionally rainy 

 seasons, and it may be prevented to a 

 large extent by draining the land, so that 

 no water lies round the collar of the plant. 

 Great care should be exercised in select- 

 ing only healthy rhizomes for planting 

 purposes, any plants with even the 

 slightest trace of disease being rejected. 

 After a bad attack it is advisable to 

 steep the rhizomes for about halt an 

 hour in Bordeaux mixture before 

 planting, to destroy any fungoid spores 

 or hyphae on their surface or in the soil 

 clinging to them. 



Another disease of ginger which does 

 some damage in Jamaica is locally 

 called "cork rot." This cannot be de- 

 tected until the crop is gathered, when 

 the rhizomes are found to be of cork- 

 like texture and quite valueless. The 

 exact nature of this disease does not 

 appear to have been investigated. 



Production op Ginger, 

 The principal sources of the ginger 

 used in Europe and America are the 

 West Indies, India, Java, Japan, and 

 Sierra Leone. In Japan particularly, 

 attention is being paid to the cultivation 

 and preparation of the better qualities 

 of ginger, such as are now produced, 



