| Cytoplasmic male sterility (CMS) is an interesting natural phenomenon resulting from the interaction between cytoplasmic and nuclear genes. which leads to the development of non functional pollens, is inherited maternally. The sterility can be restored by the nuclear positive restorer genes. To date CMS has been identified and characterized in more than 150 crop plants, which is a useful germplasm for heterosis breeding. Pepper is one of important vegetable crops. The production of the hybrid pepper seeds is tedious and costly. In order to reduce the cost, a pollination control system for the production of hybrid seeds on a large scale is also required. In this context, CMS is a valuable system for it can escape labor intensive hand emasculation procedures and achieve high purity hybrid seeds.In CMS, the materials and energy metabolism and the enzyme activity concerning the male sterility were investigated. But studies of CMS of pepper on anther development and the factors responsible for pollen abortion have not been elucidated sufficiently. The object of this study was to ascertain the stage of abortion in a CMS pepper through bud paraffin transverse sections and to illuminate the causative factors responsible for pollen abortion through some biochemical means using the anther of K132A and maintainer K132B at the different development stage as to provide some basic knowledge for unveiling the abortion of CMS. Meanwhile some hybrid breeding using the CMS line have been performed and to provide some theoretical basis for application of CMS.The following results have been obtained:1. Observations of different size of anther paraffin transverse sections under the light microscope showed that there was no structural difference between K132A and maintainer K132B from sporogenous mass to telophaseⅡstages. In K132B the each tetrad disintegrated and released the individual uni-nucleate microspores. The tapetum underwent lysis normaly and microspores could further develop into mature pollen grains. In K132A, however, the enlarged (full of liquid) tapetum has been found and pressed by the abnormally swollen tapetum, the locule became very narrow, at last the locule became much narrower and formed"L"type .The irregular tapetum make the microspores impossible to absorb the nutrition and lead to the collapse of anther locule pressed by the abnormal tapetum and induce to male sterility. The abortion happened at the tetrad stage.2. Proline content in anther showed that the content of proline in the male sterile line was lower than in the maintainer line. During the bud developing period the content of proline increased with bud development in maintainer line. However, it decreased in CMS line. Proline is the important material for pollen metabolic mechanism. Its inculmate keeps the normal biochemical activities through middle pH value. From this view, we consider that the lower proline content was one of the factors responsible for the male sterility.3. An investigation into biochemical aspects of Peroxidase(POD) , Polyphenoloxidase (PPO) , Catalase (CAT) , Superoxidase dismutase(SOD) in anther using the anthers from K132A and its maintainer line K132B has been performed. Results showed that the activities of POD, PPO and SOD in male sterile line were significantly higher than that in maintainer line at the corresponding development stages. At the mean time, they increased with the bud development in K132A while it decreased in K132B.The activity of CAT in male sterile line was lower than that in maintainer line, suggesting that the unbalance enzyme activities might be responsible for the male sterility in K132A.4. Soluble protein content in the anther of male sterile line is lower than that in the maintainer line. With the bud development the content of soluble protein at the big and middle bud stage was lower than that at the small bud stage in CMS whereas it was higher than that at the small bud stage in maintainer.5. During the spring and autumn the male sterile line was transplanted in different sites (Hangzhou, Inner Mongolia, Xinjiang ). The male sterility is stable under the different conditions based on the 100% male sterility.The male sterility was not influenced by climate. Under the net covered condition 20 fruits have been investigated in 50 plants. They were seedless and shriveled smaller size compared with the normal ones. It also confirmed the stable male sterility. Maintainer and restore lines have been bred by testcross and backcross methods.One variety has been bred in which the horticulture traits were good. It can be cultivated during the summer season in Huazhong region. The yield was 5000kg/667㎡.Cytoplasmic male sterile lines have been preserved. The commercial hybrid seed production of pepper has been performed using the CMS.
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