Abstract of an address on 'plant breeding in the United States Department of Agriculture' / by Erwin F. Smith.

  • Smith, Erwin F. (Erwin Frink), 1854-1927.
Date:
1907
Catalogue details

Licence: In copyright

Credit: Abstract of an address on 'plant breeding in the United States Department of Agriculture' / by Erwin F. Smith. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    and expressed himself as feeling that the whole year had been wasted. I cheered and encouraged him as best I could and ad\nsed him to continue. The key to the situation was obtained the next year. Subsequently the work was carried out as follows, Mr. Orton receiving great assistance from some of the growers, particularly from Mr. Rivers, on whose plantation the very resistant “Rivers Cotton ” originated; In fields much subject to this disease it was observed that here and there a plant came to maturity and bore fruit. The seeds were selected from these unusually resistant plants, and the following spring they were planted on land subject to the disease. Many of the resultant plants contracted the disease, but a considerable proportion remained free from it or practically free. Selections this year were made from the most resistant plants, having an eye also to obtaining plants with other good qualities, such as productivity, shape of boll, length of fibre, &c. The same method was pursued the following year. In the course of four years plants were obtainal with good productivity, good quality of fibre, and marked resistance to disease. Such plants stood up and bore a good crop on fields where the ordinary cotton made a total failure. The fungus was frequently found in the small roots of such plants, but it seemed to have lost its destructive power. For some years now the Department has sent out quantities of this cotton seed to the growers, and they have also quite generally begun to make selections for themselves from resistant plants. It is about seven years since this work was begun, and the growers now no longer fear this disease. Fields which were abandoned are again under cultivation, and the problem appear.^ to be solved. Melon.—Mr. Orton has also had charge of the work of obtaining resistant varieties of watermelons to replace varieties much subject to a soil disease which I was able to demonstrate to be similar to the cotton disease, i.e. due to a soil Fusarium. There are large areas in the United States (parts of Carolina, Georgia, Florida, and Texas) where this watermelon disease has prevailed to such an extent that the growing of melons on a commercial scale has been abandoned.* The melon is much more subject to this soil disease than the cotton to its disease {i.e. it is a less woody and less resistant plant), so that the disease often makes a clean sweep of the fields. The plants are attacked in all stages of growth, but will often appear to be all right until the melons are half-grown, and then suddenly the entire plant wilts and dies within a day or two, and the water-conducting system in the stem of the plant is then found to be plugged by the fungus, which enters through the root system. I have sometimes seen large fields in which there was scarcely a healthy plant. The extent of infection in the melon rendered it practically impossible to obtain any resistant plants by the process applied to cotton, namely, by simple selection. !Mr. Orton found, however, that a plant known as the “ citron ” in the United States—that is, a vine t with deeply lobed leaves and * In 1899, in the Southern States, a total of 117,551 acres were planted in water- melons (U.S. census of 1890). This statement sufliciently shows the importance of the crop. t English renders must bear in mind that in America all trailing plants are called “ vines.” What is here meant is the race of hard-fleshed very firm melons which are used for the making of preserves. Since these are used for the same purposes as the true citron of commerce, they are colloquially known as “ citron.s.”—Ed.