Breeding behavior at successive generations following hybridization in soybeans

Abstract

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The estimation of cross yield using early generation and parental yields in dry beans (Phaseolus vulgaris L.)

“…The low yielding crosses could therefore be rejected without fear that a large number of high yielding crosses were being discarded. This is in marked contrast to the results reported for soya beans (KALTON, 1948;WEISS et al, 1947), where even when all the generations were grown in the same year, there was no relationship between cross yields over generations. The authors attributed this failure to strong, but inconsistent selection pressure for maturity caused by the time of the first frost at the end of the growing season of the previous year.…”

“…Varieties or crosses that are genetically low yielding, but which have a measure of resistance to pests and diseases, as might occur in wild, weedy or primitive types, may perform better in stress situations than varieties or crosses of high yield potential but no resistance. This effect is similar to that of frost in determining yield and maturity in soya bean crosses (KALTON, 1948, WEISS et al, 1947. Therefore to select crosses or genotype of high yield potential, it is important to analyse and separate possible confounding factors which may cause yields to vary.…”

Evaluation of selection indices and homeostatic effects in soybean populations

“…Bulk populations were of limited predictive value for lodging and height, while measurements of yield and maturity had little meaning as bulk population measurements. Similarly, Kalton (1948) reported that ?£ spaced plant and line yield tests were of little predictive value, while P2 spaced plant meas urements for plant height and maturity provided good estimates of progeny performance. Significant genotype x environment interactions were reported by Torrie (1958) for several plant characters in soybeans.…”

The efficiency of some selection methods in populations resulting from crosses between self-fertilizing plants

“…Because of the gene interaction mentioned, the cultural value (phenotype) of a heterozygous plant is not a reliable guide to the value of the lines which may be derived from it . In fact plants that might segregate valuable gene combinations after selfing, could easily get lost, if plants, dominant or intermediate for some detrimental genes, are eliminated from highly heterozygous populations by means of phenotypic selections (1,4,9) . 3 …”