蚕豆脱壁花粉的萌发和胚囊分离的研究

Study on the Germination of Dewall Pollen and the Isolation of Embryo Sac in Vicia faba L.

蚕豆成熟花粉在含有20％蔗糖、100ppm硼酸的培养基中,在25℃下,40分钟后萌发率达60％左右,而脱去外壁时的花粉,在上述条件下不能萌发。若含2.0％蔗糖的1/2MS培养基中(pH5.8),培养30分钟后萌发率可达7.4％,加入2,4—D2mg·L^(-1)时,萌发率达到9.8％左右。脱壁花粉萌发率明显低于未处理的花粉,表明花粉外壁的存在对花粉萌发有明显影响,2,4—D对萌发有促进作用。蚕豆胚珠在含4％果胶酶、1.5％半纤维素酶、1％葡聚糖硫酸钾、1％CaCl_2和10％甘露醇的培养液中(pH5.7),30℃下保温12小时胚囊得率约20.3％。先用脱壁剂振荡处理除去珠被角质层,再用上述培养基培养8小时可得胚囊37.8％。用染色法和酶法证明胚囊具有活性。表明除去角质层可缩短酶解时间,并提高同步性。

When the mature pollen of bean is cultured in medium containing 20% sucrose and 100ppm boric acid , 25℃, 40min. the germinated rate of pollen is up to 60%. When the outer wall is divorced from the pollen by dewall reagent, the protoplasmic membrane becomes naked in germinal aperture. When cultured in the medium described above, the pollen can't germinate. Germinated rate reaches 7. 4% in medium containing 1/2 MS, 2% sucrose, pH5. 8, after 30 min. When 2,4-D 2. Omg ·L-1 added to the medium, germinated rate is about 9. 8%. Obviously, the germinated rate of dewall pollen is lower than that of untreated pollen. The results suggest that the outer wall of pollen has a marked influence upon pollen germination. 2,4 -D promotes germination. The bean ovule is directly suspended in the enzyme solution containing 4% (w/v) pectinase, 1. 5% (w/v) hemicellulase, 3% (w/v) cellulase, l%(w/v) potassium dextran sulphate, 1% CaCl2 and 10% mannitol , pH5. 7, 30癈 ,within 12h. On this condition, the intact rate of embryo sac is 20. 3%. If bean ovule is previously treated with dewall reagent, the cuticular layer will be divorced from ovule. Then it is cultured in the medium mentioned above for 8h. , the intact rate reaches 37. 8%. The embryo sac shows the living property when examined by stained and enzymic methods. The results suggest that it hastens the decomposition when the cuticular layer is divorced.