02057naa a2200181 a 450000100080000000500110000800800410001910000190006024501070007926000090018652015410019565000100173670000150174670000170176170000180177870000260179677300530182214771662018-06-11       1995    bl uuuu     u00u1 u    #d1 aBORRERO, J. C.  aGenetic variances for tolerance to soil acidity in a tropical maize population.h[electronic resource]  c1995  aSoil acidity reduces yield on approximately 10% of the maize (Zea mays L.) area in developing countries. Information on the inheritance of acid-soil tolerance would help scientists chose more appropriate methods for efficient breeding of tolerant cultivars. We used a North Carolina Design II mating system to study the relative importance of additive (VA) and dominante (VD) variances and their interactions with environments in the 'SA-4' tropical maize population. One-hundred-sixty S1 lines were randomly assigned to 20 sets of eight lines. Within each set, four lines were arbitrarly designated as males and four as females. Each male was crossed with each female in the et, providing 16 full-sib familes. The 20 sets, with 16 full-sib families each, were field-planted in two replications in one non-acid- and four acid-soil environments during 1992 in Colombia and Brazil. Across acid soils, VD was significantly greater than VA for yield (0.22 vs. 0.09) and days to silk (2.33 vs. 1.35) and lower for ear height (23.93 vs. 37.48), ears/plant (0.0013 vs. 0.0018), and ear rot (4.86 vs. 13.68). Heritabilities, based on half-sib family means, averaged 0.39+/-0.14 for yield, 0,43+/-0.14 for days to silk, 0.66+/-0.13 for ear height, 0,47+/-0.14 for ears plant-1, and 0,48+/-0.14 for ear rot across the acid-soil environments. Magnitudes of VA and VD and their interactions with environments indicated that reciprocal recurrent selection, using multilocation testing would be effective for developing improved maize cultivars (...)  aMilho1 aPANDEY, S.1 aCEBALLOS, H.1 aMAGNAVACA, R.1 aBAHIA FILHO, A. F. C.  tMaydica, Bergamogv. 40, n. 3, p. 283-288, 1995.