Study On Morphology And Cytology Male Sterility Of Cell Nucleus In Watermelon

Watermelon is an important horticultural crop. There is about 1470000hm~2 watermelons growing area per year in China. China is the biggest country of watermelon production and consumption in the world. To reduce the cost and to raise the benefits of seed production and to ensure raising seed purity are important aspects of utilization of heterosis. To funding, research and utilization of male sterility is a key measure to solove the important subjects. The foundation that gewic male sterility of the watermelon is very weak, getting behind the cotton, paddy rice corn etc . DT2-3 is male sterility plant, which was systematic selected from germplasm "sugarlee" of the United States. Its cytology and morphology is basically blanked yet. DT2-3 was used as experiment material, which was researched from cytology and morphology. For inquiring into that mechanism of male sterile material, and speeding up the progress of utilization. The main results were as follows:1. Development of fertile male flowers was normal, and its anthers released normal pollens when flowers opened. Male sterile flowers bloomed like fertile male flowers. But its degenerated anthers and petals were small than those of fertile ones, and its petals were slight yellow, anthers were unnormal.2. Seen form the cross section, fertile male nature flowers had normal pollens, sterile male flowers were abnormality without pollens.3. The microsporecyte meiosis was abnormal and defeat to form microspore tetrad. The abnormal cell with multiple layer, the size become smaller and pressed tightly. This abnormal deposition influence the exchange of material, energe and information between tapetum and microsporecyte and cause degeneration of medicates in sterile anthers.