影响红掌愈伤组织诱导、增殖和芽分化的因素

以P ink champ ion等盆栽植株和试管苗为材料,研究了影响红掌愈伤组织诱导、增殖和芽分化的因素。结果表明,不同品种的愈伤组织诱导率和外植体褐变率均存在显著差异,诱导率和褐变率之间呈显著的负相关关系。外植体、外源激素和培养基对愈伤组织的诱导有显著影响,不同品种和外植体的适宜诱导培养基不同。光照对愈伤组织的诱导有显著的抑制作用;高浓度生长素、低浓度细胞分裂素,促进愈伤组织的增殖,高浓度细胞分裂素及低浓度生长素促进愈伤组织芽分化;固体培养比液体培养更有利于愈伤组织的增殖和芽分化。

不同有机添加物对番茄愈伤组织诱导及芽分化的影响

本试验以番茄"中蔬六号"品种为材料,研究了不同有机添加物对番茄子叶愈伤组织诱导及芽分化的影响。结果表明,在添加各种有机的MS培养基上外植体的诱愈率均达到100%,但在诱芽方面,添加N&N有机最有利于番茄芽的再生,诱芽率达到85.7%;其次是MES,诱芽率为70.83%;单加MS有机对芽分化效果最差,诱芽率仅为55.67%。本结果对今后番茄的再生具有一定的参考价值。

韭菜根再生相关因素的研究

以韭菜"汉中冬韭"品种为试材,本试验筛选了种子消毒的最佳方法和不定芽生根的最佳培养基,研究了不同激素组合对韭菜根尖不定芽再生的影响。结果表明,韭菜种子表面消毒采用70%乙醇浸泡30s,再用0.1%升汞消毒10min为宜;以根尖为外植体,诱芽的最佳BA、NAA培养基组合为MS+BA2mg/L+NAA1mg/L,诱芽率为45.33%;如果加入KT,最佳组合为MS+BA1mg/L+NAA1mg/L+KT1mg/L,诱愈率为50%,芽分化率为38.89%。不定芽生根的最佳培养基为MS+IAA0.3mg/L,IAA浓度过大,反而抑制生根。另外,不同基因型的芽分化频率略有差别,以"汉中冬韭"品种最好。

影响小白菜子叶再生的因素

本研究以小白菜"杭州油冬儿"品种为试材,研究了不同激素组合、子叶不同部位、不同接种方式对不定芽再生的影响,并且还筛选了种子表面消毒的最佳方法和不定芽生根的最佳培养基。研究结果表明,白菜种子表面消毒的最佳方法为用70%的乙醇浸泡30s,再用20%的次氯酸钠消毒20min或用0.1%升汞消毒10min;以完整的带柄子叶为最佳外植体,接种时将子叶背面朝上放置比正面朝上放置更有利于不定芽的分化;子叶再生的最佳培养基为MN+BA2mg/L+NAA0.5mg/L,不定芽生根的最佳培养基为1/2MS+IAA0.2mg/L。此研究为小白菜再生体系的建立奠定了基础。

Callus Induction from Mature Embryos of Maize

In this study we studied the factors influencing the callus induction from mature embryos of maize inbred lines Qi 319, Zhen 58, Chang 7 -2, Lx 9801 and 81162, such as genotype, combination of plant growth regulators, and low-temperature pretreatment. The results showed that the induction rate of Qi 319 was the highest among the four genotypes tested; combination of 4.0 mg/L 2,4-D ＋ 0.5 mg/L 6-BA was suitable for inducing callus from mature embryos; three days of 4℃ pretreatment can promote the callus induction significantly. The indices optimized in the present study are helpful for establishing genetic transformation system in maize without considering seasonal variation.

A Genetic Transformation System for Rosa multiflora Thunb. var. cathayensis Rehd. et Wils through Callus Induction

An efficient genetic transformation system is a preparation for Rosa multi-flora Thunb. var. cathayensis Rehd. et Wils to diversify its flower color through ge-netic engineering. We firstly optimized the explants and culture conditions on callus induction, hormone concentrations and dark period of culture time on bud differentia-tions in particular, with sterilized seedlings to establish the regeneration system of R. multiflora. It showed that callus induction frequency reached 100% after the ex-plants being cultured in dark for 21 d when MS was chosen to be the initial culture medium. The bud differentiation rate was 48% after cal i being cultured under dark for 8 d on MS medium supplemented with TDZ （1.5 mg/L） and NAA （0.05 mg/L）. The cal i was used as the explants that were infected with Agrobacterium tumefa-ciens harboring a DFR-RNAi construct. The transformation rate reached as high as 50%. The establishment of a highly efficient rose gene transformation system out-lined in this report is prerequisite for genetic improvement in rose flower colors.

A Preliminary Study on Callus Induction and Proliferation of Cylocarya paliurus

[Objective] To carry out preliminary study on callus induction and prolifer- ation of Cylocarya pafiurus. [Method] The leaf and stem segments of Cylocarya paliurus as explants were cultured on MS, WPM and improved DKW3 mediums, added 6-BA and IBA with different concentration ratios to explore the optimum medium for callus induction and proliferation. [Result] It was found that MS ＋ 4.0 mg/L 6-BA ＋ 2.0 mg/L IBA was the optimum medium for inducing stem callus of Cylocarya pali- urus, MS ＋ 2.0 mg/L 6-BA ＋ 0.5 mg/L IBA was the optimum medium for inducing leaf explants callus of Cylocarya paliurus, and MS ＋ 1.0 mg/L 6-BA ＋ 1.0 mg/L IBA was the optimum medium for callus proliferation. 200 mg/L Vitamin C was best to inhibit Cylocarya paliurus callus from browning with the browning rate of only 5.71%. [Conclusion] This study provided some theoretical basis for the establishment of tis- sue culture and rapid propagation system and the development of molecular breed- ing study of Cylocarya paliurus.

Effects of Four Culture Media on Callus Induction Rate of Wheat Anther

Effects of four culture media including MS, N6, C17 and K on wheat anther callus induction in vitro culture were studied. The results showed that the callus in- duction rate of four kinds of culture medium was in the order of K〉C17〉N6〉MS.

Callus induction from leaves of different paulownia species and its plantlet regeneration

The experiment was carried out on five different species of Paulownia for callus induction from leaves. MS medium was adopted as basic medium, and from different combinations of NAA and BA the suitable media were determined for callus induction, bud differentiation, and root differentiation of five different species. MS+0.5NAA+4BA, MS+0.3NAA+2BA, MS+0.5NAA+4BA, MS+0.3NAA+6BA, and MS+0.3NAA+8BA were suitable media of callus inductions of leaves, respectively, for Paulownia tomentosa, Paulownia australis, Paulownia fortunei, Paulownia elongata and P. tmentosa x P. fortunei, and MS+0.3NAA+12BA, MS+0.3NAA+12BA, MS+0.5NAA+12BA, MS+0.5NAA+12BA, and MS+0.7NAA+12BA were suitable media for bud differentiation from leaf callus respectively for above five species. The rooting media was determined as 2MS+0.1NAA, 1/2MS+0.1NAA, 1/2MS, 1/2MS+0.3NAA, and 1/2MS+0.5NAA. These results provide reference data for breeding new fine va-rieties with different kinds of Paulownia protoplasts fusions.

Optimization of Callus Induction Medium for Schisandga chinensis Baill via Uniform Design

[Objective]This study was to optimize callus induction medium for Schisandga chinensis Baill.[Method]Using callus induction rate as an indicator,uniform design was employed to optimize hormone combination at poly-factors and poly-levels for callus induction from Schisandga chinensis Baill.[Results]Optimal hormone combinations depended on different explants：optimum medium for both tender leaf and petiole was MS ＋3 mg/L 6-BA,for stem segment was MS ＋3 mg/L 6-BA ＋0.6 mg/L NAA.[Conclusion]Uniform design is a time-saving and convenient method for the optimum medium for callus and yields a higher callus induction rate.

Differences in Primary Callus Induction among Different Anthurium andraeanum Varieties

[Objective] This research aimed to optimize continuously the highly efficient regeneration system of Anthurium andraeanum. [Method] The leaves and petioles of four A. andraeanum varieties were used as explants to investigate the differences in primary callus induction among different A. andraeanum varieties. [Result]The callus formation capacity of SAM and SST was stronger than that of SDM and SHG. Among the four varieties, the leaf regeneration capacity of SAM, SDM and SHG was stronger than the corresponding petiole regeneration capacity. However,the petiole regeneration capacity of SST was stronger. The optimum medium for petiole callus induction of SST was 1/2 MS ＋ TDZ 4.0 mg/L ＋ 2, 4-D 0.2 mg/L with induction rate of 87.5%; the optimum medium for leaf callus induction of SAM was 1/2 MS ＋ TDZ 2.0 mg/L ＋ 2, 4-D 0.2 mg/L with induction rate more than90%; the optimum medium for leaf callus induction of SDM and SHG was all 1/2MS ＋ ZT 2.0 mg/L ＋ 2, 4-D 0.2 mg/L with induction rates of 59.34% and 79.63%,respectively. [Conclusion] In addition to variety differences, the differences in differentiation ability among different types of calluses should be also taken into account in the establishment and optimization of tissue culture and rapid propagation technology system of A. andraeanum.

Research on Callus Induction from Coleoptile Explants of Amorphophallus

[Objective] The aim was to explore the ways of callus induction and the effect that different culture condition exerted on the callus induction from coleoptile explants of Amorphophallus. [Method] The test used konjac coleoptile as materials and designed four hormones, including 6-BA, NAA, KT and 2, 4-D, grouping 8 treat- ments to conduct statistics on callus induction in different test conditions. [Result] The result showed that multi-location generation and polymorphism was the impor- tant feature of callus induction from coleoptile explants of Amorphophallus; culture condition had significant influence on callus induction from coleoptile explants （P〈 0.01）. [Conclusion] It reached the best effect of callus induction when the culture condition was MS ＋ 1.0 mg/L 6-BA ＋ 2.0 mg/L NAA or MS ＋ 1.0 mg/LKT ＋ 2.0 mg/L 2, 4-D.

Effects of 2,4-D and 6-BA on Callus Induction and Plantlet Regeneration from Mature Embryos of Hsien Rice

[ Objective] In order to study the effects of 2,4-D and 6-BA on callus cultivation from mature embryos of hsien rice. [ Method] 2,4-D and 6-BA were set at different concentrations in callus induction and differentiation mediums to study their effects on callus induction, seedling formation and regenerated seedlings rooting. [ Result] In the callus induction medium treated with 0.5 mg/L 2,4-D, the callus induction effects on the varieties like Jiayu 948, Yanghui 559, Yangxian 6547, Zhong＇erruanzhan, Minghui 86, Guanghui 998 and Zunxian 3 were the best; If 0.2 mg/L 6-BA was added into the callus induction medium containing the optimum level of 2,4-D, there was no obvious effect on induction rate of callus, but the differentiation and seedling of callus were inhibited; If the concentration of 6-BA was reduced appropriately in the differentiation medium, the seedling rate of callus would be not only no decreased but increased, meanwhile the quality of regenerated plants would be improved. [ Conclusion] The study results provided some references for the reasonable uses of 2,4-D and 6-BA in callus culture of hsien rice.

Optimization of the Callus Induction System of Chenopodium quinoa Willd

Callus induction effects of nine varieties of Chenopodium quinoa Willd. were compared by taking stem segments and cotyledons of C. quinoa as the ex- plants. At the same time, callus JnductJon of stem segments was optimized, as well as the callus proliferation system. Research results showed that the optimal explant for callus induction was stem segment. The average callus induction rate of nine varieties reached 90% in culture medium MS ＋ 0.5 mg/L 2, 4-D. In the callus opti- mization test, treatment VI （MS ＋ 0.5 mg/L 2, 4-D ＋ 0.5 mg/L KT ＋ 0.5 mg/L NAA） and treatment II （MS ＋ 0.5 mg/L 2, 4-D） had close induction rate, but the callus morphology was greatly different. The latter had loose, glossy and yellowish white calluses. Therefore, culture medium MS ＋ 0.5 mg/L 2, 4-D was the optimal for callus induction. And using 2, 4-D together with KT and NAA could significantly increase the proliferation rate of calluses.

The BUD2 mutation affects plant architecture through altering cytokinin and auxin responses in Arabidopsis

The ratio of auxin and cytokinin plays a crucial role in regulating aerial architecture by promoting or repressing axillary bud outgrowth. We have previously identified an Arabidopsis mutant bud2 that displays altered root and shoot architecture, which results from the loss-of-function of S-adenosylmethionine decarboxylase 4 （SAMDC4）. In this study, we demonstrate that BUD2 could be induced by auxin, and the induction is dependent on auxin signaling. The mutation of BUD2 results in hyposensitivity to auxin and hypersensitivity to cytokinin, which is confirmed by callus induction assays. Our study suggests that polyamines may play their roles in regulating the plant architecture through affecting the homeostasis of cytokinins and sensitivities to auxin and cytokinin.

Study on the Callus Induction and Petiole Proliferation of the Wild European Plum

[Objective]To establish the callus induction and proliferation system of the petiole of the wild European plum.[Methods]The petiole of the wild European plum was used as an explant.The effects of disinfection time,type and concentration of carbon source,dark treatment time,basic medium,growth regulator and sampling time on callus induction and petiole proliferation were studied.[Results]The best sampling time was from mid-May to mid-June.The lowest pollution rate was 3.33%when they were disinfected with 75%alcohol for 45 s and 0.1%mercuric chloride for 7 min.21 d of dark treatment was the best dark treatment time.The best formula for callus induction and proliferation was:B5+0.2 mg/L 6-BA+2 mg/L NAA+30 g/L sucrose+7 g/L agar.[Conclusion]A theoretical foundation was laid for the tissue culture and regeneration system of the wild European plum.

Effect of Different Plant Growth Regulators on Callus Induction and in vitro Rapid Propagation of Wild Petunia Juss.

In this study,the seeds of wild Petunia Juss.were used as explants to investigate the optimal condition for tissue culture.Several different kinds and concentrations of growth regulators were adopted to produce more multiple bud clumps,callus or roots in this study.The experiments may provide experimental foundation for the rapid propagation technology and establishment of tissue culture system for wild Petunia Juss.

Influences of antibiotics on plantlet regeneration via organogenesis in loblolly pine (Pinus taeda L.)

Three antibiotics ampicillin, carbenicillin, and cefotaxime were evaluated for their effects on induction, growth, and differentiation of organogenic calli, as well as rooting of regenerated shoots of three loblolly pine (Pinus taeda L.) genotypes. Of the antibiotics administered, cefotaxime maximally increased the frequency of callus formation and growth rate of organogenic calli, carbenicillin maximally increased the frequency of shoot regeneration and the average number of adventitious shoots per piece of organogenic callus, ampicillin maximally decreased the rooting frequency of regenerated shoots and mean number of roots per regenerated shoot, in comparison with antibiotic-free media. Compared with the control, ampicillin minimally increased the frequency of callus formation, cefotaxime minimally increased the frequency of shoot regeneration, and carbenicillin mini-mally decreased the rooting frequency of regenerated shoots in three loblolly pine genotypes tested. All three antibiotics in-creased the frequencies of callus formation and shoot regeneration, and reduced the rooting frequency of regenerated shoots suggested that the establishment of an efficient Agrobacterium tumefaciens-mediated transformation protocol for stable integra-tion of foreign genes into loblolly pine need to select a suitable antibiotic. This investigation could be useful for optimizing genetic transformation of conifers.

Preliminary Investigation on Somatic Embryogenesis from Immature Cotyledon Explants of Shea （Vitellaria paradoxa G,）

Long juvenile phase and lack of effective protocols for large scale vegetative propagation are limitations to domestication and improvement of the shea tree. The present study seeks to develop a protocol for plant regeneration of shea （Vitellaria paradoxa） from immature cotyledon explants. Embryogenic callus cultures were induced on Murashige and Skoog medium （MS） containing 3% sucrose, 0.24% Phytagel, and various concentrations of 2,4-Dichlorophenoxyacetic acid （2,4-D） after four weeks of culture in darkness. Rates of embryogenic callus induction were significantly affected by the addition of 2, 4-D to the medium. Within 28 days of culture, the highest percentage of embyogenic calli （77.61%） occurred on MS media containing 0.45 ~tM of 2,4-D in the dark. Somatic embryos were obtained by culturing embryogenic callus （in the dark） on MS medium fortified with 3% sucrose, 0.24% phytagel and devoid of growth regulators. Culturing at 16 h photoperiod restricted both the induction of embryogenic calli cultures and somatic embryos. Somatic embryos germinated, developed shoots and rooted vigorously on MS medium devoid of growth regulators. Germinated plantlets were acclimatized, successfully.

Effect of Salinity Stress and Mutagenic Sodium Azide on Callus Induction and Plant Regeneration of Borage （Borago officinalis） in Vitro

The effect ofmutagenic NaN3 at concentration （0.0, 2.0 and 4.0 mM） and salinity stress at the levels （6.5, 8.5, 10.5 and 12 dS/m） on the seeds germination, callus induction and plant regeneration fi＇om stressed callus of different borage explants were investigated. The results showed that （4.0 mM） NaN3 with 4 h incubation period increased germination percentage reached 83.3% rate. Moreover the responses of different explants for callus induction in the presence of different combinations from auxin and cytokines were varied and a combination of（2 mg/L ）from each of BA and IAA gave high callus fresh weight reached （229.6, 218.0, 237.3） for （shoot tips, cotyledon leaves and hypocotyls） respectively .Concerning to the effect of salinity stress on callus induction and plant regeneration a high reduction in callus flesh weight and plant regeneration were observed at the high level of NaCl.