猕猴桃种间远缘杂交胚珠培养

Study on ovule culture from inter-specific hybrids in Actinidia

狗枣猕猴桃(Actinidiakolomikta)在远缘杂交过程中容易落果,无法获得杂交后代,针对这一问题以中科院武汉植物园猕猴桃资源圃中狗枣猕猴桃为母本,4倍体中华猕猴桃雄株(A.chinensis)为父本进行种间远缘杂交,授粉后29、45d小心剔取胚珠接种于培养基上,4℃条件下暗处理2周后转移至光下培养,每4周继代1次,当幼苗生长高度达3cm以上且根系发达时炼苗移栽。结果显示,培养基MS+GA30.2mg/L+NAA0.2mg/L+ZT1.0mg/L上,胚珠的萌发率最高,达到36.67%,在培养基MS+GA30.5mg/L+NAA0.5mg/L+6-BA2.0mg/L上,幼苗长势好,而培养基1/2MS+IBA0.7mg/L对根系的发育具有良好的促进作用。

Actinidia kolomikta is a good breeding material due to its high nutrition, cold resistance and smooth pericarp, but up to now people haven＇t obtained its hybrids. In this study the interspecific crossed fruit, obtained from A. kolomikta and A. chinensis grown in kiwifruit orchard, Wuhan Botanical Garden, were used as materials for ovule culture. Ovules were picked out from young fruit at 29, 45 day after pollination, and cultured in dark under 4℃ for 2 weeks, then transferred to light at 25℃. The results indicated that the ovule germinated well on the culture media of MS＋ GA3 0.2 mg/L＋ NAA 0.2 mg/L＋ ZT 1.0 mg/L, and the shoots grew well on the culture media of MS＋GA3 0.5 mg/L＋ NAA 0.5 mg/L＋ 6-BA 2.0 mg/L, and the culture media 1/2MS ＋ 1BA0.7 mg/L was beneficial for roots development. In this experiment, we fortunately obtained hybrids through ovule culture in the genus Actinidia, and this system was primarily established as a base for creating new germplasm for further interspecific hybridization in the genus A ctinidia.