Study On The Anther Culture And Microspore Culture Of Capsicum Annuum L.

In vitro anther culture and microspore culture were now routinely used for producing homozygous materials quickly for hybrid breeding program. To promote pepper (Capsicum annuum L) hybrid breeding in BVRC (Beijing Vegetable Research Center), anther and isolated microspore culture techniques of pepper were investigated.25 genotypes of pepper were used as materials. Factors influencing embryogenesis of anther culture of pepper were studied, which include genotypes of the material, plant hormones in the culture medium, pretreatment of the anthers and other culture conditions. At the same time, isolated microspore culture technique was studied, first to find how to gain clean microspores with high vitality and the conditions of inducing microspore differentiation.Relationship between developmental stage of microspore and the size of flower buds was examed. The ratio of petal and calyx could be used as a standard to indicate the developmental stages of microspores in the buds. When the ratio was about 1, most of the microspores contained in anthers were at the stage of late uninucleate with the nucleus close to the cell wall, but it depended also on the materials.Genotype was the most important factor affecting anther culture. In tested genotypes, only 8 of 25 ones induced embryoids. Hormone was another significant factor. Results showed that the most suitable hormone and perfect concentration varied from one genotype to another. High concentration of hormone could hasten embryogenesis of genotypes with a relatively good inducing ability, while it could induce embryogenesis in genotypes with no reaction under low hormone concentration. But high hormone concentration in anther culture seems to be unfavouring of plant regeneration from these embryoids.Callus formation showed also to be genotype dependent. When a certain amount (0.2%-0.5%) of activated charcoal was added to the medium during anther culture, antherbrowning and callus formation could be reduced along with embryogenesis advanced.In anther culture, the ideal preculture temperature changed with genotypes. It was 32℃ in Al 7 and 29 in Al 8. Light treatment at the early stage of anther culture was of no good to embryo inducing, which lead anthers to brown seriously.In microspore culture, activity of microspores was assayed according to different age of donor plants and different genotypes. It varied among different genotypes and different age of the donor plants in the same genotype. The higher embryogenesis frequency thegenotype had the more activity the microspores had. To get clean and active microspores, low speed centrifuge (300rpm) was recommended during microspore collection and purification.It was found that PM medium did not suit for isolated microspore culture of pepper, because microspore activity decreased rapidly on this medium. On the contrary, the swelling and division of microspores were observed for medium MS, NLN and SNGM. The latter's looked suitable for pepper microspore culture and worth further researching.It was recommended that microspores first be culture at 35℃ or at 32℃ less than 24 hours according to the activity survivor and cell division. Low temperature and mannitol pretreatment favor the maintaining of microspore activity. In anther perculture, microspores could be released from anther soon by shaking at 100 rpm in liquid medium, and cell dividing was favored in this culture type. In 6 genotypes, A45 and A46 formed callus.