Establishing Introduced Varieties

The exploration for suitable breeding varieties and their importation (or reimportation) was considered the foundation of the investigation, but within a few months, while plans were being perfected, that part of the project was interrupted by the outbreak of war. It was not resumed until late 1943, but during the interim some progress was made in obtaining seed from Africa and India by correspondence. The resumption of plans for original collecting in Africa during the war was stimulated by the developing need for large quantities of industrial alcohol in the manufacture of explosives. Sorgo of available varieties had been planted around Louisiana sugar factories in 1942 for that purpose and about a quarter million gallons of alcohol were produced, but the acre yield of fermentable raw material was not up to expectations. The rapid development of higher yielding varieties adapted to the local conditions and suited to the less exacting requirements for alcohol production in contrast with sugar production was believed possible.

With the objective of obtaining seeds for the dual purpose of emergency alcohol production and long-term investigation of sugar production, the writer left Washington December 9, 1943, and arrived at Addis Ababa, Ethiopia, 5 days later.

Many other countries in Africa have well-organized departments of agriculture able to furnish information and technical assistance, but in Ethiopia the agricultural explorer is entirely on his own scientifically and must dig out independently all information and collections of plants.

The head of agricultural services in Addis Ababa gave assurance that there were indeed two kinds of mashela (sorghum) in Ethiopia, the red and the white. But the peasants of the "out back," who sometimes had to be interviewed through a chain of interpreters, knew of many different kinds and were mines of information on them. Eighty distinctly different varieties of sorghum, including two that grow wild, were obtained in Ethiopia during the winter of 1943-44.

Seed of the 80 varieties were shipped by air to Washington and distributed to five stations ranging from the Panama Canal Zone, 9° north, to Beltsville, 37° north. At Beltsville, where they were planted in the greenhouse on March 25, the majority grew to a height of 15 to 20 feet by the end of July and produced seed heads. In contrast, the growth rate at the Meridian, Miss., station was somewhat retarded by drought. Growth rate at Canal Point, Fla., and Summit, C. Z., was about the same as that in the greenhouse at Beltsville. The average growth rate and total growth of many varieties were actually greater at these stations than in Ethiopia, but the average quality of juice was not up to that of the best quality, low-tonnage local varieties.

A succession of plantings of the latter was started on different dates in Florida in an attempt to synchronize the flowering of the local and the newly imported varieties, and it was possible to make the desired crosses with a small part of the Ethiopian varieties in the first year, 1944. The first-generation (Fi) hybrids were planted at -Meridian in 1945 and were first analyzed in August and September. Although the hybrids will segregate into different forms in future generations, the F, results give a good index of the future breeding possibilities of a cross and the first analyses were encouraging in stalk weight and sugar content. Two progenies of the cross Straightneck M. N. X Saragie M. N. 684 gave the following results, in which the sugar content is fair and weight of stalk is two and one-half times that of the domestic parent.

The unfinished job of assembling varieties from equatorial Africa was resumed in September 1945, when Carl O. Grassi started collecting in the Sudan, and progressed through Kenya, Tanganyika, Nyasaland, Northern Rhodesia, and Uganda. With splendid cooperation from agricultural departments and other agencies that aided in original collecting and also furnished seed from their own collections, he has added more than 1,000 accessions of seed to the rapidly growing African collection established in the United States. Only a few of these appear to duplicate varieties previously collected.

Besides the personal collecting, which is always preferable and sometimes indispensable, many accessions of seed have been obtained by correspondence. By persevering effort, more than 200 packets of seed were obtained during 1942-44 from 16 countries, a gratifying testimonial to the cheerful cooperation of foreign colleagues during that time of interrupted and difficult communications. Of the number received, including many important ones, 131 came from India and the rest from countries in Africa. A possibly important source not represented in the recent collections is that part of China extending from 110° to 120° E. in approximately the latitude of Shanghai. The Indian and Chinese sources in which we have interest correspond to ancient dispersal areas that have become secondary centers of origin of domesticated sorgos. They are important for new and more thorough investigation because of the chance that some varieties may possess one or more qualities desired in our present project and, by their location, may be assumed to be reasonably well adapted to our conditions.