杏胚珠培养及幼胚子叶不定芽诱导研究

以盛花后25、35、50、55、60d的凯特杏胚珠为外植体,研究胚珠培养的适宜条件;选择发育一致的幼胚子叶,研究不定芽的发生条件。结果表明,SH培养基是凯特杏胚珠培养的适宜培养基;盛花后25d的凯特杏胚珠(PF=0),仅采用生长培养不足以发育成可见胚,试验采用诱导方式获得了可见胚,诱导出胚率为80%;以MS为基本培养基,BA与NAA结合诱导能力强;但这种胚小且瘦弱,继续生长培养,利用幼胚子叶诱导不定芽。在幼胚子叶诱导不定芽方面,盛花后25、35d取样的凯特杏胚珠,培养后获得幼胚子叶,诱导不定芽的适宜TDZ质量浓度为1.25mg/L,诱导出芽率分别为85.00%、80.00%;盛花后50、55d取样的材料,适宜TDZ质量浓度为2.50mg/L,出芽率分别为65.00%、60.00%,而盛花后60d取样的材料,适宜TDZ质量浓度为5.0mg/L,出芽率为61.11%,不定芽主要发生在子叶的近轴面、胚轴连接处及子叶近轴端两侧;在相同培养基中,25℃进行21d暗培养,盛花后35、50、55、60d材料出芽率分别为72.22%、65.00%、60.00%、55.56%;4℃下28d暗培养,35、50、55、60d依次为59.09%,71.42%、77.78%、86.36%;对不定芽进行伸长、生根与快繁培养,获得了健康正常的植株。通过以上研究,建立了凯特杏幼胚4级培养体系,即(1)胚珠培养,获得可见胚(1级培养);(2)幼胚生长培养(胚培养),获得了健壮幼胚(2级培养);(3)幼胚子叶再生,获得不定芽(3级培养);(4)不定芽组培苗快繁(4级培养)。

Ovule culture and adventitious bud regeneration from immature cotyledons of apricot

In vitro culture was carried out using ovules of Katy (Prunus armeniaca L.) obtained 25,35,50,55 and 60 days after blossom stage, respectively, to identify favorable conditions for ovule culture. Immature cotyledons of same growth stage were employed to elucidate appropriate conditions for adventitious buds promoted. The results showed that SH culture medium was better than MT culture medium for ovule culture of Katy. Because ovules gathered 25 days after blossom were too young, inducement treatment, in combination with growth culture was performed to obtain visible embryos with embryo producing rate up to 80%. And integration of BA with NAA displayed stronger inducement ability than with IBA, with MS being basic culture medium. Immature cotyledons of Katy from ovules gathered 25 and 35 days after full bloom require 1.25 mg/L TDZ and rate of adventitious buds was 85.00% and 80.00%, the adventitious buds filled up proximal region of cotyledons. Whereas, immature cotyledons from ovules sampled 50 and 55 days after full bloom require 2.50 mg/L TDZ and rate of adventitious buds were 65.00% and 60.00% and sampled 60 days after full bloom require 5.0 mg/L TDZ adventitious buds rate was 61.11% and adventitious buds were mainly regenerated at proximal regions, hypocotyl joints and both sides of the proximal regions, etc. In terms of favorable conditions for regeneration from immature cotyledons of Katy, condition of 25 ℃ and 21 days for dark culture for immature cotyledons from ovules sampled 35,50,55,60 days after full bloom, adventitious buds rate were 72.22%,65.00%,60.00% and 55.56% .Whereas under condition of 4 ℃ and 28 days for dark culture, regeneration rate of adventitious buds were 59.09%,71.42%,77.78% and 86.36%. According to above-mentioned studies, four class culture systems for embryo rescue of Katy were established as follows: 1. Ovule culture were carried out to obtain visible embryo (first class); 2. Growth culture of immature embryo were conducted to get fatty immature embryo (second class);3. Regeneration of immature cotyledons were conducted and adventitious buds were obtained(third class); 4. Rapid multiplication was carried out from adventitious buds (fourth class).