Preliminary Study On The Embryo Culture, The Rapid Propagating System Of The Stem Segments And Ploidy Breeding In Punica Granatum L.

The research was carried out in the laboratory of Henan Agriculture University from 2007 to 2008. The main contents were immature embryo culture conditions for natural hybrid of'Tunisian soft-seed pomegranate'and the optimizing of stem segments tissue culture system of Tunisian soft-seed pomegranate, the effects of different concentration of colchicine on germination rate and morphological change of'Dazi'pomegranate. The results of the research are as follows:1. The disinfection system of immature embryo culture of'Tunisian soft-seed pomegranate'was eatablished and the results indicated that before August 14, at the early stage of immature embryo developing, the disinfection of the whole fruit was used and the disnfecion was soaking 30s in 75% C2H5OH ; and after August 14, because of the further development of the immature embryo, the disinfection of the seed was used and the disnfecion was soaking 5min in 50%NaClO and soaking 5min in 0. 025%HgCl2 . The results also indicated that the most suitable inoculating period of immature embryo was from August 14 to September 4. The germinative rate could reach 48. 3% when immature embryos were inoculated on September 4 and been cultivated after 100d. The effects on seedling rate of immature embryo during different inoculation dates indicated that the inoculated immature embryos could develop to be seedlings after July 14 and the seedling rate of immature embryos inoculated on September 4 was the highest. The transplant survival percent of seedlings of immature embryo culture could reach more than 90% if the seedlings were been treated by suitable methods.2. The screening of the multiplication medium and rooting medium for stem segments culture of'Tunisian soft-seed pomegranate'and the results indicated that the most suitable multiplication medium was MS+1. 0 6-BA mg·L-1+0. 1 NAA mg·L-1, the multiplication index of shoot was 3. 33 and the effect of the combination of 6-BA and IBA was better than the combination of 6-BA and NAA. The most suitable rooting medium was 1/2 MS+0. 1 NAA mg·L-1, the rooting rate was 88. 5%, the new roots were stronger and the transplant survival percent could reach more than 95%. 3. The different colchicine treatment had different effects on the germination rate, the transverse diameter of embryonal axis and external status of'Dazi'pomegranate. The results indicated that the lower concentration of the colchicine the higher germination rate of the seed and the colchicine has inhibitive effect on the germination rate. The transverse diameter with colchicine treatment was wider than that's without colchicine treating. So some cells may have been doubled according to polyploid gigantic characteritics. The canopy diameter of seedlings treated with different concentration colchicine was wider than that's without colchicine treatment. So some plants may have become polyploidy. According to the synthesis comparing of the germination rate, the transverse diameter of embryonal axis, canopy diameter, the number of seedling's leaves and the seedling's height , the best result was the 0. 2% colchcine treating 48h, the second was the 0. 2% colchcine treating 24h and the 0. 8% colchcine treating 24h and the worst is the 0. 8% colchcine treating 48h in the all treatment combinations.