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Forty-one wild types and 41 cultivars of common bean (Phaseolus vulgaris) from Meso-and South America were screened for variability of phaseolin seed protein using one-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS/PAGE) and two-dimensional isoelectric focusing SDS/PAGE. Wild accessions from the Andean region showed phaseolin types which had not been previously identified in wild material from that region. Other wild accessions from Argentina exhibited novel phaseolin patterns collectively designated as ‘J’ (‘Jujuy’) phaseolin types, and one accession from northern Peru exhibited a novel phaseolin type, the ‘I’ (‘Inca’) type. The ‘H’ and ‘C’ phaseolins, previously identified only in cultivars, were observed in several wild accessions from Argentina. Among cultivars, two minor variants of the ‘S’ phaseolin type were identified. The ‘Sb’ (‘S Brazil’) was characteristic of a limited number of cultivars from Brazil whereas the ‘Sd’ (‘S Durango 222’) predominated in cultivars of the Mexican central highlands. The distribution of the previously described ‘B’ phaseolin appeared to be larger than formerly known as it extended not only in Colombia but also in Central America. It is possible to correlate the ‘Sb’, ‘Sd’, and ‘B’ phaseolin types with certain agronomic traits.

Soybean [Glycine max (L.) Merr.] seed protein extracts from 1,603 accessions obtained from 15 Asian countries or regions (not including Japan) were analyzed for the presence of alleles of 2 proteins. Three alleles of the Kunitz. trypsin inhibitor orSBTI-A 2 designated asTi a,Ti b andTi c are electrophoretically distinguishable from one another by their different Rf values of 0.79, 0.75 and 0.83, respectively. The Sp1 seed protein or β-amylase has 2 alleles designatedSp1 a andSp 1 b which are electrophoretically distinguishable from one another by their Rf values 0.36 and 0.42. About 94 percent of the soybean accessions had theTi a allele. Two accessions from Korea,P.I. 157440 andP.I. 196168, do not have theSBTI-A2 protein(ti). Two accessions, one from Pakistan and the other from Korea, were identified as having theTi c allele. Only the Korean and central Indian soybean populations have a high frequency for theTi b allele. Within Korea, the soybeans from those districts that lie closest to Japan have a high frequency for theTi b allele whereas the soybeans from those districts that lie closest to China have a low frequency for theTi b allele. TheTi b allele is not present in soybeans from the Philippines, Vietnam, Thailand, Malaysia, Burma, Nepal, Pakistan, and Afghanistan. Only 1 accession each from Taiwan and Indonesia have theTi b allele. TheSp 1 a allele is not present in soybeans from Taiwan, Vietnam, Thailand, Malaysia, Indonesia, Burma, Pakistan and Afghanistan. The highest frequency for theSp1 a allele occurs in soybean germ plasm from northern India and Nepal. The soybeans from Asia (including Japan) were divided into 3 gene centers— primary, secondary, and tertiary—containing 7 germ plasm pools. Paths of dissemination of the soybean from China to the rest of Asia were developed based upon a combination of electrophoretic data and available historical, agronomic, and biogeographical literature.

A sample of 106 wild forms and 99 landraces of common bean (Thaseolus vulgaris) from Middle America and the Andean region of South America were screened for variability in phaseolin seed protein using one-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS/PAGE) and two-dimensional isoelectric focusing SDS/PAGE. The Middle American wild forms exhibited phaseolin patterns similar to the ‘S’ pattern described previously in cultivated forms, as well as a wide variety of additional banding patterns—‘M’ (Middle America) types—not encountered among common bean cultivars. The Andean wild forms showed only the ‘T’ phaseolin pattern, also described previously among cultivated forms. Landraces from Middle America showed ‘S’ or ‘S’-like patterns with the exception of 2 lines with ‘T’ phaseolin. In Andean South America, a majority of landraces had the ‘T’ phaseolin. Additional types represented in that region were (in decreasing order of frequency) the ‘S’ and ‘C’ types (already described among cultivated forms) as well as the ‘H’ (Huevo de huanchaco) and ‘A’ (Ayacucho), (new patterns previously undescribed among wild and cultivated beans). In each region—Middle America and Andean South America—the seeds of landraces with ‘T’ phaseolin were significantly larger than those of landraces with ‘S’ phaseolin. No significant differences in seed size were observed among landraces with ‘T,’ ‘C,’ ‘H,’ and ‘A’ phaseolin types of the Andean region. Our data favor 2 primary areas of domestication, one in Middle America leading to small-seeded cultivars with ‘S’ phaseolin patterns and the other in the Andes giving rise to large-seeded cultivars with ‘T’ (and possibly ‘C,’ ‘H,’ and ‘A’) phaseolin patterns.

Phaseolin seed protein variability in a group of 8 wild and 77 cultivated common bean (Phaseolus vulgaris) accessions was determined using 1-dimensional SDS/ PAGE and 2-dimensional IEF-SDS/PAGE. Wild common bean accessions exhibited the 'CH' and 'B' patterns, previously undescribed among either wild or cultivated common beans. The cultivated genotypes showed (in decreasing frequency) the previously described 'S,' T,' and 'C phaseolin patterns as well as the new 'B' pattern similar to the pattern identified in a Colombian wild common bean accession. In the northeastern part of the Colombian bean-growing region, the cultivars exhibited almost exclusively an 'S' phaseolin type, while in the south-western part, the 'T' and 'C phaseolin cultivars were more frequent. Seed size analysis indicated that 'T' and 'C' phaseolin cultivars had larger seeds than 'S' and 'B' phaseolin cultivars. Our results suggest that Colombia is a meeting place for Andean and Middle American common bean germplasms, as well as a domestication center for the common bean.

An extensive literature survey on seed proteins has been made, with attention given to both amino acid composition of various seed proteins and the total quantity of protein produced by the seeds. Data have been grouped according to botanical classifications and correlations drawn where possible. The various plant families have been rated according to their protentialities as protein-producing seed crops in the United States. As a beginning towards filling in some obvious gaps in amino acid composition data, amino acid assays have been carried out for the first time on nine species of seeds.