Genetic Studies On The Main Quality Characters Of Multiple Recessive Homozygotes Of Sweet Corn

In this study, the multiple recessive homozygous sweet corns were used as materials. A series of agronomic characters were studied, and the main quality characters of kernels were studied in the filling period. The correlation between quality characters, parts of agronomical characters and yield characters were studied. The broad-sense heretabilities and genetic advances were estimated. The main results were as follows:(1) The days to emergence, tassel, pollen and silk for most of multiple recessive homozygous combinations were earlier than both parents or situated between parents. The days to three-leaf for most of them were longer or situated between parents. The plant height and ear height of them were higher or situated between parents. And the stem diameter of them was larger or situated between parents. The emergent ratio of autumn seeding was worse and the growing period was shorter than that of spring seeding.(2) The yield of dry kernel, parts of yield characters and embryo weight ratio for most of multiple recessive homozygous combinations were higher or situated between parents. The embryo weight ratio of them was higher than that of the two checks. The 100-kernel weight, ratio of kernel of them and the kernel weight per plant and dry yield for most of them were lower than those of the two checks. The other characters were similar to those of the two checks. The results of autumn seeding were not completely same as those of spring seeding.(3) The soluble sugar content of kernel was negative correlated with the days in the stage from 18 to 27 days after pollination, and a few of correlation coefficients were significant. The periods of highest soluble sugar content for most of multiple recessive homozygous combinations were shown in the stage from 15 to 18 days after pollination. And the highest content for most of combinations was higher or situated between parents. The soluble sugar contents between crosses and their reciprocal crosses were not significantly different. The sugar content of autumn seeding was relatively higher than that of spring seeding on the same day after pollination.(4) The moisture content of kernels were reduced and significantly negative correlated with the days from 18 to 30 days after pollination. The moisture means from 5 measurements for most of combinations were higher or situated between parents. The speed of reduction for moisture content of autumn seeding was faster than that of spring seeding. The moisture contents of crosses were not notably different with reciprocal crosses.(5) The protein means from 6 measurements for most of combinations were lower or situated between parents. And the protein content did not vary too much in the stage from 18to 30 days after pollination. The periods of highest protein contents of combination were shown in the harvesting period. The results of autumn seeding were similar to those of spring seeding. There were some differences to reciprocal cross.(6) The oil content was increasing with the days after pollination. The highest oil content for most of combinations was shown in the harvesting period. The highest oil content for most of combinations was higher or situated between parents. The oil content of multiple recessive homozygous materials was higher than the checks. The results of autumn seeding were similar to those of spring seeding. And there was not significant difference to reciprocal cross.(7) The mean value of pericarp thickness for most of multiple recessive homozygous combinations was thicker than parents or situated between parents in the stage from 18 to 30 days after pollination. The pericarp thickness for most of combinations was not differences from that of the corresponding parents on the same day after pollination. And there was not significant difference to reciprocal cross.(8) Paricarp thickness was significantly and positively correlated with the yield of fresh ear on the 18th day after pollination. And the other 4 quality characters were not significantly correlated with the yield of fresh ear.