Effect of Phytohormones on Adventitious Bud Differentiation from Bulb Scales of Oriental Lily Test-tube Plantlets

[Objective] The purpose of this study is to investigate the effects of differ- ent phytohormones on the adventitious bud differentiation of oriental lily. [Method] The bulb scales of the test-tube plantlets of Tiber, Rodina and Constanta were cul- tured in media supplemented with different cytokinin and auxin at different concen- tration, and then the adventitious buds in each treatment were calculated. [Result] Cytokinins had different influence on the adventitious bud differentiation of the three oriental lily cultivars. Among them, 6-BA had the best effect to induce the adventi- tious bud differentiation from bulb scales of Tiber and Rodina, but there was some difference in the optimal concentration. KT had the best effect to induce the adven- titious bud differentiation of Constanta. The auxins had little influence on the quality of the adventitious bud of the three oriental lily cultivars, but caused some difference in differentiation coefficients. [Conclusion] The most suitable media for the adventi- tious bud differentiation from bulb scales in vitro of Tiber, Rodina and Constanta were MS＋0.2 mg/L 6-BA＋0.2 mg/L 2,4-D, MS＋I.0 mg/L 6-BA＋0.2 mg/L IAA, MS＋ 1.0 mg/L KT＋0.5 mg/L 2,4-D, respectively.

Effects of Sodium Chloride Stress on Growth of Sweet Potato Plantlets in vitro and Ion Content

[Objective] This study aimed to investigate the salt-tolerance mechanism of sweet potato.[Method]Two sweet potato varieties of Xu 25-2(salt-tolerant cultivar)and Triumph 100(salt-sensitive cultivar)were treated by sodium chloride with the concentration of 0 mmol/L and 100 mmol/L.After 20 days,Na+ content and Na+/K+ ratio in the roots,shoots and leave were determined by the flame photometer,while dry weight and fresh weight of roots,shoots and leave in different varieties were also studied.[Result]The growth of two sweet potato varieties was inhibited under salt stress,so the plant became shorter,leaf and root became fewer,dry weight of roots and leave decreased,but seedlings of Xu 25-2 were inhibited slightly.Furthermore,Na+ content and Na+/K+ ratio in roots,shoots and leaves of two sweet potato varieties increased.Na+ content of salt-tolerant Xu 25-2 was low in roots,shoots and leaves,while Na+ content of salt-sensitive Triumph 100 was high in shoots and leave of seedlings,but the change range of Xu 25-2 was less than that of Triumph 100.[Conclusion]The lower Na+ content and Na+/K+ ratio in leaves under salt stress were the most important characteristics for salt-tolerance of sweet potato varieties.

秋水仙素对大蒜茎尖试管苗四倍体的诱导

【目的】大蒜为无性繁殖作物,难以采用常规育种方法选育新品种,而化学诱变作为种质创制的重要方法之一,在一些作物上获得了较好的效果。探讨秋水仙素对大蒜茎尖组培试管苗多倍体的诱变效应,旨在为创新大蒜种质提供理论依据和技术方法。【方法】选用山东‘苍山蒲棵’、四川‘正月早’和‘新疆紫皮’3个生态区域的大蒜品种,鳞茎经自然晾干通过休眠后,取鳞芽茎尖为外植体接种到不同处理的培养基上,采用二次饱和-D最优设计方法,研究秋水仙素不同浓度及处理时间对大蒜茎尖试管苗成苗率及染色体加倍率的影响,并建立相关回归模型;通过对回归模型进行解析,确定诱变大蒜四倍体的优化方案;采用流式细胞仪检测幼叶和根尖压片染色体计数相结合的方法进行染色体倍性鉴定。【结果】利用流式细胞仪检测的四倍体大蒜植株叶片DNA相对含量是二倍体对照大蒜‘苍山蒲棵’的2倍;通过染色体计数法鉴定二倍体植株根尖染色体为2n=2x=16,而四倍体植株染色体为2n=4x=32。在秋水仙素处理大蒜茎尖诱变四倍体过程中,随秋水仙素处理浓度的升高及时间的延长,3个大蒜品种试管苗成苗率均逐渐降低,且处理浓度的影响大于处理时间;品种间成苗率存在显著差异,以‘正月早’较高,‘新疆紫皮’次之,‘苍山蒲棵’较低,其处理间平均成苗率分别为48.69%、46.73%和41.83%。秋水仙素对大蒜四倍体的诱变效应以处理浓度大于处理时间,不同大蒜品种对秋水仙素的反应存在显著差异,虽然‘苍山蒲棵’、‘正月早’与‘新疆紫皮’的最高四倍体诱导率分别达15.69%、15.69%和23.53%,但大蒜四倍体平均诱导率则以‘正月早’最高,‘苍山蒲棵’次之,‘新疆紫皮’最低,分别为9.15%、7.84%和6.53%。经计算机模拟寻优,求得的3个大蒜品种试管苗成苗率均超过50%的处理方案为秋水仙素浓度为0.268%—0.694%、处理时间为61.1—113.8 h;3个大蒜品种四倍体诱导率均超过5%的秋水仙素处理浓度和时间分别为0.531%—0.580%和79.8—112.2 h。【结论】不同大蒜品种对秋水仙素处理浓度和处理时间的反应不同,秋水仙素对大蒜四倍体的诱变效应亦存在显著差异,但均以处理浓度的影响大于处理时间,且处理浓度与处理时间存在互作效应。3个大蒜品种成苗率超过50%且四倍体率超过5%的秋水仙素处理浓度为0.531%—0.580%、处理时间为79.8—112.2 h。

不同诱变剂对大蒜四倍体诱导的影响

为探讨不同诱变剂对大蒜茎尖试管苗成苗率和四倍体率的影响,采用二次饱和-D最优设计方法,以氨磺乐灵、二甲戊乐灵和秋水仙素作为诱变剂,以大蒜品种金乡紫皮茎尖为材料,采用流式细胞仪分析和根尖压片染色体计数相结合的方法进行染色体倍性鉴定。结果表明,氨磺乐灵、二甲戊乐灵对大蒜茎尖试管苗平均成苗率和四倍体率的影响均显著高于秋水仙素。分别为62.58%和20.92%、60.95%和23.20%、44.28%和12.25%,但3种诱变剂不同处理组合对大蒜茎尖成苗率影响存在显著差异,均以低浓度处理较短时间成苗率较高,而在较高浓度长时间处理下,成苗率降低。3种诱变剂诱导大蒜四倍体率的最佳处理浓度和时间也不同,且以氨磺乐灵、二甲戊乐灵诱变处理显著优于秋水仙素。经模拟运算,三者诱变大蒜茎尖的最佳处理浓度和时间分别为4.17~8.52 mg·L-1和71.14~118.03 h、4.68~8.90 mg·L-1和72.96~106.18 h、3.87~6.94 g·L^(-1)和67.92~114.43 h。本试验初步明确了3种诱变剂对大蒜茎尖试管苗四倍体的诱变效果,为进一步开展大蒜四倍体新品种选育奠定了基础。

同源四倍体泡桐体外植株再生系统建立

以叶片为外植体,建立了同源四倍体兰考泡桐和白花泡桐体外植株再生系统.结果表明,同源四倍体兰考泡桐和白花泡桐幼苗叶片愈伤组织诱导的最适培养基分别为MS+NAA 0.3 mg.L-1+BA 8 mg.L-1和MS+NAA 0.1 mg.L-1+BA 10 mg.L-1;愈伤组织芽诱导的最适培养基分别为MS+NAA 0.7 mg.L-1+BA 14mg.L-1和MS+NAA 0.1 mg.L-1+BA 12 mg.L-1;幼芽生根的最适培养基皆为1/2 MS.

四倍体酸枣组培苗移栽研究

以四倍体酸枣生根组培苗为试材,研究炼苗天数、基质种类、空气相对湿度、组培苗高度、根条数及移栽时间对组培苗移栽成活率和生长的影响。结果表明:移栽应在4月底至6月进行,在此时期选择高度大于5cm,根7条以上的组培苗,经炼苗3天,移栽至纯蛭石或珍珠岩与土(1:1)或蛭石与土(1:1)中,移栽前期保持空气相对湿度在90%以上,移栽成活率可达70%以上。

黄瓜（Cucumis sativus L．）组织培养与诱导四倍体再生植株

应用杨行黄瓜、长春密刺、农大秋光和杂种群丰、津研四号、津杂四号等黄瓜的子叶、真叶、茎段为外植体，离体培养诱导再生植株。比较了细胞分裂素（ＫＴ）与不同浓度的２，４－Ｄ和ＮＡＡ配比对诱导黄瓜愈伤组织的影响，及其所产生的愈伤组织分化培养的成苗率。所得结果表明：黄瓜在组织培养再生植株时，对生长激素极为敏感，只需极低浓度的２，４－Ｄ或ＮＡＡ即能诱导大量愈伤组织。激素浓度增高，出愈率提高，愈伤组织增殖加快，但分化能力下降。ＮＡＡ诱导成的愈伤组织比２，４－Ｄ诱导的易于分化。在诱导愈伤组织及胚性细胞发生时加入５００ｍｇ·Ｌ－１的秋水仙素经振荡液体培养４８，７２，９６ｈ再进行分化培养，出苗率分别为２５．６％、１８．５％、０．９％，对照为４６．８％。再生植株中３．５％～４．５％为四倍体，秋水仙素在分化培养中有抑制作用，处理９６ｈ的则很少分化再生植株。

饲料型四倍体刺槐组培苗的遗传学鉴定

以饲料型四倍体刺槐的自然繁殖苗木为对照,对组培苗进行RAPD技术分析,结果表明,经NAA处理的组培苗未发生遗传变异,而经IBA培养的组培苗发生了遗传变异。

内蒙古野生黑果枸杞四倍体试管苗的创制与繁殖

以二倍体内蒙古野生黑果枸杞种子为材料,利用不同浓度秋水仙素处理加倍,然后通过流式细胞仪筛选解离液,测定细胞核DNA含量,同时观察苗期叶片气孔数量和大小以及根尖压片确定染色体数量完成倍性鉴定,最后对加倍获得的四倍体株系进行组织培养扩繁。研究结果表明:秋水仙素适宜浓度为0.2%、处理60h时野生黑果枸杞种子变异率最大,为20.63%。流式细胞仪鉴定,筛选出Galbraith′s为黑果枸杞最适解离液,发现四倍体黑果枸杞细胞DNA相对含量比二倍体增加1倍。四倍体植株气孔数较二倍体植株显著减少而气孔明显增大。根尖压片确认,二倍体染色体数目为2n=2x=24,加倍植株染色体数目为2n=2x=48。最后成功对四倍体株系进行了组织培养扩繁。本试验获得了黑果枸杞四倍体株系,建立了一套高效、准确的内蒙古野生黑果枸杞多倍体(四倍体)创立技术,并成功进行四倍体试管苗扩繁。四倍体黑果枸杞新种质资源的创制,为内蒙古乡土野生黑果枸杞新品种的研发提供了物质基础,同时为内蒙古新种质资源的研究奠定了理论基础和技术参考。