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Cotton, sugarcane, rice, maize, yuca, bananas, flax and olives grow on the coastal lowlands; oca, ullucu, añu, quinua and temperate climate fruit trees in the mountains; cinchona, coffee, mahogany, Spanish cedar, palms, bamboo and cubé in the forested montana.

The methods and techniques of cacao selection and breeding are discussed in relation to the problems of the San Thome industry. A general survey of the cacao crop was carried out in order to determine the varieties grown, the range of variability in the local population, disease incidence and cacao quality. Yield was established as the major aim in the cacao breeding program. Vigorous and early bearing genotypes are also desirable. Resistance toPliytophthora palmivora is to be considered at a later stage, when studies of the fungus and its different strains are more advanced to allow for the search of tolerant genotypes. The program includes single plant selection in the local cacao population, introduction of hybrid seed and selected parents, and single and multiple crosses among clones selected locally and abroad. Emphasis is laid on studies on the inheritance of several quantitative characters, such as combilling ability, yielding ability, vigor, and seed size. Incompatibility studies in relation to seed production and interspecific and intergenerie crosses, including studies on the cytological behaviour of the species and their hybrids, are also to be undertaken.

Oats constitute an important feed grain crop in the United States and many other countries. World production in pounds averages one- third that of wheat and two- fifths that of rice or corn. The United States and Canada produce nearly half of the world crop. Oats are utilized primarily as feed for domestic animals. Although their bone- and muscle- building ingredients and other nutrient values are well known, less than five percent of the world crop is used as human food.

The marama bean, Tylosema esculentum, is a drought- tolerant legume native to southern Africa. Its seeds are comparable to soybeans in protein content and quality, its oil content approaches that of peanuts, and the plants might be desirable as a forage legume. Although the marama bean has great potential as an arid land crop in the United States, studies of the species are extremely limited. The current investigations have demonstrated that the plants can be grown successfully in an arid region of the United States, at least under experimental conditions, and that a healthy seed crop can be expected in about 4.5 years.

Cultivars of sesame from 20 countries were sampled for morphological variability. Taximetric methods, including factor, cluster, discriminant, and principal components analyses, established patterns of similarities and were used to generate groupings among the taxa. The complementary results of the analyses indicate that 8 major groups can be discerned. Plants with tetracarpellate capsules have a distinctive form and comprise the initial separation from the entire collection on the dendrogram. The second branch is a group of purple-tinged plants from India that also includes the proposed progenitor. A short, bushy, early maturing genotype consists of predominantly Turkish cultivars. Another group, composed primarily of Korean accessions, consists of unbranched plants with strap-shaped leaves. Other groups are less easily typified. This characterization of the genetic variation in sesame can be used to identify sources of genetic materials for crop improvement, as well as to provide information about the evolution and genetic differentiation of the crop.