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The F, progenies of crosses between several cowpea (V. unguicuiata ) lines were investigated for variation of eye pattern and seed coat colour. It was found that three (W, H, O) and five (R, P, B, M, K) maior genes control eye pattern and seed coat colour, respectively. The recessive gene (oo) for restricted eye pattern enables the underlying basic white or cream seed coat colour to be observed. A similar effect is obtained with the recessive gene (n-) for colour expression. The expression of mottling (V), possibly a seed coat pattern, may not be observed when it is combined with the genes for certain eye patterns. The significance of these findings in breeding for consumer preference for specific seed coat colour i.s discussed.

Responses to two cycles of mass selection under two mating systems were compared in the F2 and F3 generations of one cross each of spring wheat (Triticum aestivum L.) and spring barley (Hordeum vulgare L.). The number of green tillers prior to head emergence was used as the critical character. Additional characters, time from sowing to flowering and fertility number at maturity, were measured also in the evaluation of selection response for green tillers. The mean response for increased tillring, evaluated at two sites against unselected control generations, was higher in the wheat at 10.3%cycle than in the barley at 6.3%/cycle. Broad sense hentability estimates for tillering were between 10 and 25% for each cross.In both species the selection responses were greater in the hybrid than in the selfed selection series. The hybrid series was obtained by random mating among the selections in each cycle. The respective responses in barley realized over two selection cycles, were 17.1% with outbreeding and 8.7% with inbreeding at site 1, and 13.9% with outbreeding and 10.3% with inbreeding at site 2. In wheat at site 1, the responses were 22.6% with outbreeding and 18.5% with inbreeding. (Site 2 of the wheat had poor establishment.) Since the same F2 selection generated the hybrid and selfed series, the differences in response were attributed to the second cycle only. Asso. ciated selection responses for time to flowering and tiller number at maturity were detected only in the wheat.The results showed that mass selection with concurrent random mating could be a useful breeding stratcgy in self‐pollinated crops.

Seed resistance of cowpea (Vigna unguiculata L. Walp.) to bruchids at the F3 plant generation was assessed by various methods. The most discriminating variable for measurement of seed resistance was mean emergence day, followed by percentage of adult emergence up to an optimum time, then in descending order, percentage of undamaged seed, mean number of holes per seed and percentage loss in seed weight. The simplest reliable variable to use for assessment of resistance to bruchids was the percentage of undamaged seed with zero emergence holes. However, greater control and manipulation of egg laying on seeds would be required to obtain uniform infestation. Three (or less) eggs per seed is suggested as acceptable. Care, particularly on the uniformity of eggs laid, is necessary when using percentage seed weight loss as an index of resistance. The other variables are laborious to estimate. In general, seed weight, number of eggs per seed, seed testa texture and number of seeds per sample did not appear to influence estimates of resistance, with the exception of seed weight loss. The natural rate of increase of bruchids, which is a critical variable for measurement of resistance, was very difficult to estimate with consistency.