Studies On The Interactive Effects Of Double Recessive Genes And Major Agronomic Characters In Sweet-waxy Maize

Waxy maize materials (wxwx) were crossed to sweet maize materials (susu) and super sweet maize materials (shsh) respectively Homozygous double recessive gene sweet-waxy maize (susuwxwx or shshwxwx) were segregated on the F1 ears Double recessive gene sweet-waxy maize and the parents sweet maize super sweet maize~. waxy maize were planted at the same time A series of agronomic characters were observed, and the interactive effects of double recessive genes in sweet-waxy maize were analysed The main results could be summarized as the follows 1 The days to emergence of double recessive gene sweet-waxy maize were similar to those of super sweet maize The days to three-leaf of double recessive gene sweet-waxy maize were the longest The days to tassels pollens silk of double recessive gene sweet-waxy maize were shorter than those of super sweet maize The plant height for most of double recessive gene sweet-waxy maize was taller than that of parents sweet maize and waxy maize The ear height of double recessive gene sweet-waxy maize situated between parents The trend of increase in plant height was induced by interaction of double recessive genes in sweet-waxy maize 2 The 100 梜ernel weight and kernel weight per plant for most of double recessive gene sweet-waxy maize situated between parents That is, they were higher than those of corresponding male sweet maize, and they were much lower than those of corresponding female waxy maize These showed that sweet gene (sh or su) was epistatic to waxy gene (wx) 3 The soluble sugar content from 15 to 30 days after pollination for most of double recessive gene sweet-waxy maize kernels was higher than that of corresponding parents waxy maize and sweet maize There were some significant or higher significant differences between the genotypes These showed the effect of positive interaction of double recessive genes, i e the interaction of double - 63 - recessive genes in sweet-waxy maize conduced to the increase of soluble sugar content. The highest soluble sugar content of double recessive gene sweet-waxy maize kernels was shown in the stage from 15 to 18 days after pollination . And its speed of decrease was very slow. 4. The moisture content for most of double recessive gene sweet-waxy maize kernels situated between parents on the 18th, 24th and 30th day after pollination. It was higher than that of corresponding female waxy maize,and it was lower than that of corresponding male sweet maize. These showed the additive effect of double recessive genes in sweet-waxy maize. 5. The mean total starch content for most of double recessive gene sweet-waxy maize kernels situated between parents or lower than that of the corresponding parents on the 18th, 24th, 30th and 46th day after pollination. The trend of decrease in total starch content was induced by interaction of double recessive genes in sweet-waxy maize. The starch of double recessive gene sweet-waxy maize was almost all arnylopectin. There was very little arnylose only. These showed that waxy gene (wx) was epistatic to sweet gene ( sh or su) for the produce of amylopectin. The interaction of double recessive genes in sweet-waxy maize conduced to the increase of the percentage of amylopectin. 6. Pericarp thickness for most of double recessive gene sweet-waxy maize situated between parents or thinner than that of the corresponding parents on the...