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Soybean [Glycine max(L.) Merr.] breeders and entomologists have primarily used field techniques to screen for insect resistance. Problems they have encountered include maturity variability among the host plants, variability in natural insect populations, and an inability to separate antibiosis from non preference. We developed a laboratory screening technique to breed for resistance to Mexican bean beetle (Epilachna varivestisMulsant). Larval mortality and development are monitored to determine the level of antibiosis in individual plants. High mortality and/or slow larval development indicate high levels of antibiosis resistance. This laboratory technique allows the breeder and entomologist to control insect pressure while screening year‐round and to eliminate the problems associated with plant maturity differences in the field. Screening of the soybean lines is started at the V3 developmental stage; thus, resistant plants can be identified prior to anthesis. This allows for crosses among resistant lines to be accomplished the same growing season. These factors significantly reduce the time needed to develop Mexican bean beetle resistant lines.

Segregation for male sterility was observed in an F3line of the soybean, Glycine max(L.) Merr., cross L67‐533 ✕ ‘SRF 300’ and designated as the Urbana Male Sterile (UMS). Segregation in this line and between‐ and within family segregation the following generation indicated UMS was controlled by a single recessive gene pair. Crosses made with the North Carolina Male Sterile (NCMS), ms1ms2, suggested that UMS and NCMS were controlled by the same gene or a different allele at the same locus. Male‐sterile plants of UMS had higher levels of female fertility than did male‐sterile plants of NCMS in various genetic backgrounds and in two diverse environments. The increased female fertility of the UMS male‐sterile plants was expressed as a higher frequency of plants with at least one 3‐seeded pod and a lower frequency of plants with no seed.

Prior research indicated that the three genes, Pd(dense pubescence), Rpsal(Phytophthoraresistance), and ln(narrow leaflet), tended to stimulate the vegetative growth of indeterminate soybean [Glycine max(L.) Merr.] near‐isogenic lines but failed to significantly increase seed yield or, in some environments, significantly decreased yields. It was postulated that this lack of a yield increase, or the occurrence of a yield decrease, may be due to the increased lodging often associated with the increased vegetative growth. These three genes were crossed into the indeterminate (lodging susceptible) and determinate (lodging resistant) near‐isogenic lines of the soybean cultivars, ‘Clark’ and ‘Harosoy’ and yield tested in the field at Urbana, IL in 1974 and 1975 to test this hypothesis. The addition of the Pdand Rpsalgenes to the indeterminate near‐isogenic lines increased plant height and lodging but decreased yield. In the determinate near‐isogenic lines, where no lodging occurred, plant height was increased and yields were either increased or there was no difference in yield. The effect of the lngene was similar to the Pdand Rpsalgenes in the Clark cultivar, but differed in the Harosoy cultivar. Results of this research strongly support the hypothesis that failure of the vegetative growth stimulating genes, Pdand Rpsal, and to a lesser extent the lngene, to increase seed yields, or in some cases significantly decrease yields, in the indeterminate near‐isogenic lines is duet to the increased lodging associated with the increased vegetative growth. These data indicate that in evaluating genes which stimulate vegetative growth, care should be taken to evaluate them in a genetic background where lodging does not become the yield limiting factor.

Government bodies worldwide are moving toward accepting soy proteins in their food supplies. There is a trend toward food laws that allow countries to take advantage of unique nutritional, functional and economic benefits soy protein has to offer. This is a world precedent, soundly based on broad experiences and firmly backed by scientific research and development. There is no longer any need to postpone this important decision to allow soy protein in the food supply. The most critical question at this point should be: “What steps can be taken now to properly incorporate and take advantage of soy protein in the national food supply? Regulations recognizing the benefits of soy protein in the food system need not be complex. A reasonable approach to food legislation attempts: (a) to allow the production of properly labeled, safe, wholesome foods, recognizing new developments in modern food technology; (b) to ensure the nutritional value of foods; (c) to provide sufficient information and understanding to help the consumer make a wise purchase decision; and (d) to adopt controls as required to promote honesty and fair dealing in the marketplace.

The net photosynthetic rate of the terminal leaflets of the first five trifoliolate leaves of nine varieties of soybean (Glycine max(L.) Merr.) was sudied inf rared‐gas analysis. The variety ‘Hark’ was found to photosynthesize at a significantly higher rate than either ‘Chippewa 64’ or ‘ADO0.’ A large amount of variability was observed in plant to plant observations within the same variety. After an adjustment was made to remove this variability, significant differences were observed among the varieties tested.

The screening and testing program the US Environmental Protection Agency (EPA) is currently developing to detect endocrine-disrupting chemicals (EDCs) is described. EDCs have been shown to alter the following activities: hypothalamic-pituitary-gonadal (HPG) function; estrogen, androgen, and thyroid hormone synthesis; and androgen and estrogen receptor-mediated effects in mammals and other animals. The value and limitations of mammalian in vivo assays are described that involve the use of the laboratory rat, the EPA Endocrine Disruptor Screening and Testing Advisory Committee species of choice. The discussion includes the evaluation of high-priority chemicals positive in the Tier 1 Screening (T1S) battery, and of subsequent testing in the Tier 2 (T2) battery, with additional short-term screening assays proposed for use in T1.5 to eliminate any uncertainty about T1S results. Descriptions include the in vivo uterotropic assay, which detects estrogens and antiestrogens; the pubertal female assay, which assesses steroidogenesis, antithyroid activity, antiestrogenicity, and HPG function; and the Hershberger assay, which detects the weight of androgen-dependent tissues in castrate-immature-male rats (antiandrogens). Of the several alternative mammalian in vivo assays proposed, a short-term pubertal male rat assay appears most promising for inclusion in T1 or T1.5. An additional in utero-lactational screening protocol is being evaluated, but appears to be better suited for T1.5 or T2 due to the size, complexity, and duration of the assay. The adult intact male assay, also proposed as an alternative for T1, attempts to ide.jpgy EDCs in a hormonal battery, but has limited value as a screen due to lack of sensitivity and specificity. For Tier 2 testing, the number of endocrine-sensitive endpoints and offspring (F1) examined in multigenerational tests must be thoughtfully expanded for EDCs on a mode-of-action-specific basis, with consideration given to tailoring T2 based on the results of T1S.