麻竹愈伤组织的诱导培养

麻竹[Sinocalamus latiflora(Munro)McClure(Bamboo)]是一种经济价值高的笋材两用竹。用麻竹笋箨片作外植体在含有2,4—D 4～8mg/L和KT3 mg/L、蔗糖5％、琼脂0.7％～0.8％的MS基本培养基上诱导出愈伤组织.在同样的培养基或添加部分其它养分及激素的培养基上继代培养,愈伤组织能持续生长.

苦丁茶愈伤组织诱导培养初步研究

苦丁茶是近年来从野生资源中开发利用的非茶类植物，具适应性广、成材快、经济价值高等特点，可作代用茶，并有药用功能。用苦丁茶嫩梢茎切段及带柄叶片作外植体，在含２，４－Ｄ０５ｍｇ／Ｌ～４ｍｇ／Ｌ、ＫＴ１ｍｇ／Ｌ、蔗糖３０ｇ／Ｌ、琼脂７ｇ／Ｌ的改良ＭＳ培养基上，诱导产生愈伤组织，在同样培养基或添加不同附加物的培养基上继代培养。

多油辣木PKM-1花药培养获得愈伤组织

【目的】针对多油辣木(Moringa oleifera Lam.)PKM-1品种内高度杂合、种性容易退化的问题,拟通过花药培养获得双单倍体植株,实现品种内纯合。【方法】基本培养基MS添加激素2,4-D和NAA,诱导多油辣木PKM-1花药愈伤组织,对花药愈伤组织进行秋水仙素加倍,以及添加6-BA、KT和NAA分化植株。【结果】PKM-1花药愈伤组织形成与2,4-D密切相关,2.0 mg/L时愈伤组织平均诱导率6.0%;NAA诱导花药愈伤组织,效果不明显。秋水仙素和处理时间对辣木花药愈伤组织染色体加倍具有剂量效应,0.6%秋水仙素处理72 h和0.8%秋水仙素处理48 h获得相同加倍效率,二倍体诱导率达60%。没有添加秋水仙素的对照,也形成少量二倍体愈伤组织,说明辣木花药愈伤组织存在一定比例的自然加倍。添加不同浓度6-BA、KT和NAA,诱导辣木花药愈伤组织分化,但均未分化出胚状体。【结论】本研究初步建立了多油辣木PKM-1花药培养获得愈伤组织的技术体系,但分化完整植株有待进一步研究。

In vitro callus induction and plantlet regeneration of Achyranthes aspera L.,a high value medicinal plant

Objective:To study callus induction from different explants(internode,leaf,root)and in vitro plantlets propagation from medicinally important plant Achyranthes aspera L.Methods:Sterilized explants were prepared by uning 0.1%HgCl_2 and 0.5%Bavistin and callus was obtained when cultured onto Murashige Skoog's(MS)medium by using different concentrations and combination of 2,4-D.NAA.BAP,IAA,IBA with 3%sucrose and 0.8%agar.Induced callus was immediately transferred to MS medium containing at different concentrations of phytohormones for shootlets and rootlets induction respectively.Results:Sterilization treatment of 0.1%HgCl_2.for 2-3 min and Bavistin 0.5%for 10-12 min showed the highest percentage of asepsis and survival rate.Maximum induction of callus was obtained from a combination of 2.0 mg/L 2,4-D and 0.5 mg/L NAA from leaf.Highest shootlets number(4.83±0.l7)and length(3.8±0.16)cm were observed on full strength MS medium when fortified with BAP 4.0 mg/L and KIN 0.5 mg/L.Concerted efforts of BAP 10 mg/L and NAA 0.5 mg/L on full strength MS medium showed highest leaf number(6.77±0.94).In vitro raised shoots were allowed to root on different strengths of MS medium fortified with IAA and IBA at different concentrations.Experimentally,3.0 mg/L IBA was enabled to induce maximum rootlets number(10.0±9.82)on full strength MS medium.Afterwards,regenerated shoots with well developed roots were successfully subjected to hardening process and were acclimatized.The survived plantlets showed 66.67%survival frequency without any morphological abnormality.Conclusions:The results demonstrated that different explants were good source of callus induction,morphology analysis as well as indirect plantlets regeneration.

Proline and Glutamine Improve in vitro Callus Induction and Subsequent Shooting in Rice

This study was conducted to evaluate the effects of proline and glutamine on in vitro callus induction and subsequent regeneration and to develop a reproducible and highly efficient plant regeneration protocol in four rice genotypes, viz. Pawana, Jaya, Indrayani and Ambemohar. Considerable variation in response to plant growth regulators and amino acid supplements used was observed in all the four genotypes. Medium supplemented with proline and glutamine was shown to be superior to medium without proline and glutamine. The best callusing from mature embryo was observed on Murashige and Skoog （MS） medium supplemented with 2.0 mg/L 2,4-dichlorophenoxyacetic acid （2,4-D）, 500 mg/L proline and 500 mg/L glutamine. Shoot induction was higher in the callus obtained from medium supplemented with 500 mg/L proline and 500 mg/L glutamine. The highest shoot regeneration frequency （83.2%） was observed on MS medium with 2.0 mg/L benzylaminopurine, 0.5 mg/L 1-naphthaleneacetic acid, 500 mg/L proline, and 500 mg/L glutamine in the callus obtained from MS medium supplemented with 2.0 mg/L 2,4-D, 500 mg/L proline and 500 mg/L glutamine. Among the four genotypes, Pawana has the highest regeneration efficiency （83.2%）, whereas the regeneration efficiency of the rest three rice genotypes was in the range of 32.0% to 72.3%. This optimized regeneration protocol can be efficiently used for Agrobacterium mediated genetic transformation in rice.

Effects of variations in culture media and hormonal treatments upon callus induction potential in endosperm explant of Barringtonia racemosa L.

Objective: To induce callus from the medicinally valuable species, Barringtonia racemosa L.(B. racemosa) whereby the formation of callus is essential for micropropagation studies and in vitro plant secondary metabolites production.Methods: The callus induction potential in B. racemosa was assessed from endosperm explant cultured on different culture media and plant hormonal treatments. Lloyd and Mc Cown's woody plant medium and Murashige and Skoog's medium were used in the study as culture media. On the other hand, various concentrations and combinations of2,4-dichlorophenoxyacetic acid(1.0–2.0 mg/L) and kinetin(0.5–2.5 mg/L) had been incorporated in the culture media to exert the effects of auxin and cytokinin on callus induction.Results: From the present study, it was found that the profuse [(1.681 ± 0.770) g fresh weight,(0.239 ± 0.239) g dry weight] and friable callus formation was optimally produced with desirable morphology and considerable percentage of callus induction(56.70%) in endosperm explants cultured on 1.0 mg/L 2,4-dichlorophenoxyacetic acid and 1.5 mg/L kinetin in Murashige and Skoog's medium.Conclusions: A reliable protocol for inducing callus formation of profuse and friable morphology in endosperm explant of B. racemosa had therefore been successfully established.

Advances in D. <i>melanoxylon</i>Investigations towards Tissue Culture: Problems and Limitations

The first attempt on D. melanoxylon tissue culture was conducted from 2010 to 2013 at a high level of expectations. A total of 500 seeds were sterilized at different concentration of reagents and inoculated at different strength of the Murashige and Skoog medium for germination to obtain disease free explants for callus induction trials. A total of 400 nodal segments obtained from germinated seeds were sterilized at different concentration of reagents and inoculated at different hormonal combinations to induce callus formation for seedling multiplication. Results from this tissue culture attempt set a foundation for tissue culture success in D. melanoxylon on the future research. Only 19.8% of seeds inoculated in half strength of Murashige and Skoog medium germinated within 7 days while only 6.8% of seeds inoculated in full strength of Murashige and Skoog medium germinated within 6 days. This germination was at sterilization of 20 minutes in 35% ethanol and 20 minutes in 2.6% sodium hypochlorite. A total of 1% of inoculated D. melanoxylon seedling fragments in Murashige and Skoog media supplemented with hormone combination at 2.0 mg/l BAP + 0.5 mg/l NAA developed callus after16 days from the inoculation day. The final weight of the callus at the last record was 0.62 g. In this induction ex-plants were surface sterilized in 35% ethanol for 20 minutes and 2.6% sodium hypochlorite solution for 20 minutes. The color of callus was green and friable in nature. Other hormonal combinations in this case did not induce callus production. These results suggested that the problems which affect seed germination in the natural environment are also reflected on germination in the Murashige and Skoog medium and in callus induction. Vulnerability to fungal attack is a limitation for successful callus induction and germination in the culture room. More research under improved sterile conditions is needed to improve callus percentage for seedling multiplication.

Sterilization of <i>Hibiscus rosa-sinensis</i>L. Vegetative Explants Sourced from Plants Grown in Open Environment and Influences of Organic Ingredients on <i>In Vitro</i>Direct Regeneration

This paper reports on the effects of organic ingredients in facilitating direct shoot regeneration from nodal explants of Hibiscus rosa-sinensis L. This paper also compares the sterilization conditions for 3 types of explants (node, internode, and shoot tip) harvested from an open field. The optimized sterilization conditions for the explants were 40% Clorox- 20 min exposure, 10% Clorox-15 min exposure, and 5% Clorox-40 min exposure for the node, internode and shoot tip, respectively. In the direct shoot regeneration using the nodal explants, we found MS medium containing 40 g/L sucrose, 0.3% (w/v) activated charcoal, and supplementations with myo-inositol, thiamine and nicotinic acid were suitable. The in vitro shoot survival rate was 30% with a mean leaf numbers of 2.68 produced, and a mean leaf length of 1.71 cm achieved after 5 weeks of culture on the modified medium.