Primary Studies On Selection Of Self-Bred Lines And Cross Breeding In Moss Rose (Portulaca Grandiflora Hook)

The moss rose (Portulaca grandiflora) is a herbaceous ornamental plants originating in South America. Whole plant fleshy, rapid growth and resistance to adverse environment, drought resistance preferred. The study on breeding of moss rose in inland far behind to abroad, the systematic study on utilization of heterosis is a blank in China. The study continue to choose good inbred lines and do cross breeding at the same time. After several generations of self-selected, five inbred lines were selected as parents, preparing 15 combinations (including 5 parents and 10F1s). By the contrast of hybrizidation between parents in five main characters, we analasize the heterosis of every character and study on inheritance laws of 4 main ornamental characters, which include plant height, plant crown, flower size and branch number; on the other hand, we use plant growth regulator to soaking moss rose seed, investigate the impact of plant growth regulator on seed germination.The main result shows as following:①By pedigree method, obtain 14 self-bred lines, seven self-bred lines have stability performance, while the other seven self-bred lines still to be further carried out select.②The number of seeds per capsule of parents compare with F1s, the result shows that: the number of seeds per capsule of parent no.6 is most and no.5 is lest in all lines, were 102 per capsule and 70 per capsule; eighty percent F1 have heterosis.③Heterosis analasis of main view shows that:plant crown and flower size have heterobeltiosis; plant height have negative midparental heterosis; branch number have midparental heterosis; the time from seed to blossom have negative heterobeltiosis.④According to the g.c.a, we should choose inbred lines no.7 as parent to breeding large flower size plant; choose inbred lines no.4 or 2 as parent to breeding more branch number plant; choose inbred lines no.5 or 6 as parent to breeding low height plant.⑤Heritility analysis shows that:the broad heritilities (h2B) of flower size is very high, this shows that this is not sensitive to environmental impact; about narrow senseheritabilies, branch number is hightest (23.02%), other characters smaller, this shows that impact of additive genes effect is small and early selection effect is ineffective.⑥The experiment of germination which deal moss rose germ with different concentrations plant growth regulators, it is show that: lmg/L and 25mg/L of GA3 concentration on the moss rose seed, germination and seedling fresh weight was significantly promoted.1mg/L of 6-BA treatment on the moss rose seed, germination and seedling quality significant promote. 1mg/L of IBA treatment can promote seed germination and seedling quality.