Effects Of Intercropping With Hybridization F₁ Generation Of Two Ecotypes Of Solanum Photeinocarpum On Cadmium Accumulation Of Cyphomandra Betacea Seedlings

The C. betacea is perennial evergreen shrub of semi woody or small arbors, fruit of C. betacea juicy sweet and sour tast, and can be used for fresh fruit, which great potential for development. But the frequent heavy metal pollution in recent years has been threatening to growth and fruit quality safety of C. betacea and other fruit trees. In this experiment, aiming to the problem of cadmium pollution in orchard soil, C. betacea seedlings were used as research materials, intercropping cadmium hyperaccumulator of B. pilosa, S. photeinocarpum, G parviflora and T. erecta with C. betacea, screen out the potential Cd-hyperaccumulator S. photeinocarpum which reduced most of the cadmium absorption of C. betacea seedling, and hybridization the different ecotype?farmland and mine? S. photeinocarpum, get the S. photeinocarpum of positive hybridization F₁ generation which female parent is S. photeinocarpum of farmland ecotype and S. photeinocarpum of negative hybridization F₁ generation which female parent is S. photeinocarpum of mine ecotype, further study the cadmium accumulation characteristics of S. photeinocarpum positive and negative hybridization F₁ generation and effects of intercropping them with C. betacea seedlings on cadmium accumulation characteristics of C. betacea seedlings, in order to screen out hybridization F₁ generation of S. photeinocarpum which could confer effective remediation of soil cadmium pollution and significantly reduce the cadmium accumulation of C. betacea seedling, to provide a reference for orchard soil cadmium pollution remediation.The main results were as follows:1. Respectively intercropping B. pilosa, S. photeinocarpum, G. parviflora and T. erecta with C. betacea seedling. The results show that intercropping with B. pilosa and T. erecta the biomass, photosynthetic pigments content, soluble protein contentand and antioxidant enzymes activity of C. betacea seedling were higher than monoculture. especially the best growth C. betacea seedling was intercropping with T. erecta, intercropping with Solanum photeinocarpum and Galinsoga parviflora the Cyphomandra betacea would be shaded and growth was inhibited. Compared with the monoculture, respectively intercropping with four kind of hyperaccumulator the cadmium content of roots of C. betacea seedling were all to reduced, especially intercropping with G. parviflora the cadmium content of roots of C. betacea seedling was lowest, compared with monoculture has reduced by 26.63%. On the shoots, respectively intercropping with B. pilosa and G parviflora the cadmium content of C. betacea seedling were all lower than monoculture, respectively intercropping with S. photeinocarpum and T. erecta the cadmium content of C. betacea seedling were all higher than monoculture, especially intercropping with S. photeinocarpum the cadmium content of shoots of C. betacea seedling was lowest, compared with monoculture has reduced by 18.15%.2. Under the condition of cadmium pollution, the biomass and photosynthetic pigments content of S. photeinocarpum of positive and negative hybridization F₁ generation was higher than parents, which has some heterosi. Cadmium content of roots and shoots of S. photeinocarpum of positive and negative hybridization F₁ generation were significantly lower than parents, and cadmium accumulation amount were higher than parents, Compared with S. photeinocarpum of farmland ecotype and mine ecotype. the cadmium accumulation amount of shoots of S. photeinocarpum of positive hybridization F₁ generation was increased by 7.70% and 1.98%, the cadmium accumulation amount of shoots of S. photeinocarpum of negative hybridization F₁ generation was increased by 10.39% and 4.52%. Biomass and photosynthetic pigments content of S. photeinocarpum of positive hybridization F₁ generation was higher than negative hybridization F₁ generation, cadmium content and cadmium accumulation amount as a whole lower than negative hybridization F₁ generation, but the difference was not significant.Analyed the DNA methylation patterns of S. photeinocarpum of parents and positive and negative hybridization F₁ generation. The results show that the total DNA methylation rate of four kinds of S. photeinocarpum with the order of S. photeinocarpum of mine ecotype>S. photeinocarpum of farmland ecotype>S. photeinocarpum of negative hybridization F₁ generation> S. photeinocarpum of positive hybridization F₁ generation.DNA methylation patterns of S. photeinocarpum of positive and negative hybridization F₁ generation relative to parents was changed by demethylation, which may activated the expression of some genes of S. photeinocarpum of positive and negative hybridization F₁ generation.3. Respectively intercropping S. photeinocarpum of parents and positive and negative hybridization F₁ generation with C. betacea seedling. The results show that the biomass, photosynthetic pigments content, soluble protein contentand and antioxidant enzymes activity of intercropping treatments were all lower than monoculture. the above shows that in the physical growth and resistance of C. betacea seedling intercropping with S. photeinocarpum were all showed the intercropping disadvantage, especially the worst growth C. betacea seedling was intercropping with S. photeinocarpum positive hybridization F₁ generation. As far as cadmium absorption concerned, respectively intercropping with S. photeinocarpum of farmland ecotype and mine ecotype the cadmium content of roots and shoots of C. betacea seedling which compared with monoculture the difference was not significant, and respectively intercropping S". photeinocarpum of positive and negative hybridization F₁ generation the roots and shoots of C. betacea seedling were all lower than monoculture, and cadmium content of roots was significantly different, especially intercropping with S. photeinocarpum of positive hybridization F₁ generation the cadmium content of roots and shoots of C. betacea seedling were lowest, compared with monoculture has respectively reduced by 13.49% and 4.08%. Respectively intercropping S. photeinocarpum of parents and positive and negative hybridization F₁ generation with C. betacea seedling, biomass and cadmium accumulation amount of S. photeinocarpum of positive and negative hybridization F₁ generation was all higher than parents, which have higher ability of remediation of soil cadmium pollution, and especially the S. photeinocarpum of positive hybridization F₁ generation was most advantageous.4. In conclusion, the intercropping patterns of intercropping S. photeinocarpum of positive hybridization F₁ generation with C. betacea most likely to achieve the remediation of soil cadmium pollution goal while reduce the cadmium accumulation amount of C. betacea.