Select The Forecast Index In Earlier On The Heterosis Of Melon

Since 1980, some academies of science and research cultivate out a series of melon species one after another, but all of them are the normal species, exist some problems on a certain degree, such as weak on the growth force, bad on the anti-disease, bad on the tidy degree, bad on fertility. In addition, the normal species easily are bred by numerous companies, and result easily in motley and retrogression, as well as big loss on production. In the metaphase of 1980', the melon's crossbreeding applying on production, making use of F1, solve completely the problem. But the dominance combination of F1 is selected out from the large quantity combination in the field coming though many years. For overcoming the blindness on choice of parents, improving the breeding efficiency, and shortening the time of breeding, the scientific research personal search after continuously from the each aspects, and hope to find out an simply way to forecast the mating combinations of heterosis intensity, and cultivate quickly the new good species. In recent years, along with the rapid development of biotechnology, domestic and international scholar studied the heterosis from the aspects of heredity, physiology and biochemistry, and developed the way of forecast heterosis, such as the physiological active material, the isoenzyme technology, the genome activity as well as the nucleus histone component analysis etc. At present has acquired the certain progress.This experiment selects 8 dominance combinations from the 150 combinations. By measurement and analysis the germination ability of melon seed, morphological indexes and physiological-biochemical indexes of seedling, select the indexes which can forecast the heterosis in forepart, find out a simply way of crossbreeding, provide the theories basis for selection parent of the heterosis breeding. The experiment shows:1.On the aspect of germination force and germination rate, the filial generation and their parents present positive correlation, but the correlation coefficient and regression coefficient don't reach remarkable level. It shows the two characters' influence is very small to their filial generations; the two characters can't be used as the forecast indexes.2.On the aspect of seedling, on the 8 morphological indexes, the regression coefficient between the filial generation and their parents, there are 6 indexes reaching the remarkable level or the most remarkable seedling of filial generations lie mainly on their parents' genetic factor under the circumstance of environment fixing, the two characters can be used as the forecast indexes.3.On the aspect of physiological-biochemical indexes, the filial generation and their parents present remarkable positive correlation at the chlorophyll a/b, the content of dissolubility protein and POD activity at the stage of cotyledon and true leaf, it's regression coefficient reach the remarkable level or the most remarkable level. The contents of the three indexes in the cotyledon is higher than in true leaf, Furthermore the three indexes and yield present the most remarkable positive correlation, can be used as the physiological-biochemical indexes what forecast the heterosis in forepart.This experiment selects 5 indexes what forecast the heterosis in forepart, including 2 morphological indexes: the dry heavy of root and the fresh heavy of seedling; 3 physiological-biochemical indexes: the chlorophyll a/b, the content of dissolubility protein and POD activity.