凝固剂对水稻花药培养愈伤组织诱导的影响

本文初步研究了不同类型的凝固剂对水稻花药培养愈伤组织形成的影响。结果发现,用Gelrite、马铃薯淀粉、甘薯淀粉,可溶性淀粉代替琼脂可明显促进水稻花药培养愈伤组织的产生而尤以5.0％马铃薯淀粉为最佳。出愈率比琼脂增加5.2倍,达液体培养水平。以8个不同基因型,为材料研究发现,5．0％马铃薯淀粉作凝固剂,有7个材料出愈率高于对照,最高的BCl63比对照增加7.75倍,平均增加1.15倍。另外,以5.0％马铃薯淀粉作凝固剂代替0.8％琼脂可降低成本30％。因此,用马铃薯淀粉作凝固剂在水稻花药培养中可能具有潜在的应用价值。     

提高疣粒野生稻愈伤组织分化能力的研究

通过低温处理、更换培养基凝固剂以及液固交替培养的方式,成功地保持了疣粒野生稻愈伤组织的胚性,提高了绿苗分化率。结果表明：低温处理12天的愈伤组织绿苗分化率最高;用琼脂糖代替琼脂作为培养基凝固剂,能在较大程度上提高愈伤组织绿苗分化率;通过液固交替培养的方式保持了悬浮系的分化潜能,在悬浮培养18个月后,绿苗分化率仍达到41.6％,而持续悬浮培养12个月的愈伤组织全部丧失分化能力。酯酶同工酶分析表明：部分酶带的丢失与愈伤组织分化能力的丧失有关。     

提高疣粒野生稻愈伤组织分化能力的研究

通过低温处理、更换培养基凝固剂以及液固交替培养的方式,成功地保持了疣粒野生稻愈伤组织的胚性,提高了绿苗分化率。结果表明：低温处理１２ 天的愈伤组织绿苗分化率最高;用琼脂糖代替琼脂作为培养基凝固剂,能在较大程度上提高愈伤组织绿苗分化率;通过液固交替培养的方式保持了悬浮系的分化潜能,在悬浮培养１８ 个月后,绿苗分化率仍达到４１ ．６ ％ ,而持续悬浮培养１２ 个月的愈伤组织全部丧失分化能力。酯酶同工酶分析表明：部分酶带的丢失与愈伤组织分化能力的丧失有关     

普通小麦单体的花药培养

近年来小麦花药培养研究资料表明,愈伤组织诱导率与材料的遗传基础有很大关系shimada等用普通小麦中国春的A组染色体的非整倍体类型进行花药培养,结果形成的愈伤组织几乎全是由花丝产生的,并发现愈伤组     

BA对大麦花药培养中药壁的衰退和植株再生频率的影响

用含20ppm 6-BA的0.1％吐温-80溶液喷施花粉为单核前期的大麦上部叶片和穗部,明显影响大麦花药培养效率。实验结果表明:1)BA处理可明显延缓培养花药的药壁衰退进程。2)BA处理后的花药,在培养期间,其死亡的花粉数比对照大大减少,相反其双核或多核的花粉数比对照明显增加。3)BA处理虽然没有促进大麦花粉愈伤组织的诱导率,但显著地促进愈伤组织的生长。提高愈伤组织成长率,增加可转入分化培养的愈伤组织块数。4)BA处理促进愈伤组织的再分化,尤其是绿苗的分化。     

放射线对水稻花药培养的影响

已有报告指出,低剂量的电离辐射能够促进水稻和芸苔(Brassica napus)花药培养中胚胎发生愈伤组织的诱导和生长。在1991年细胞和组织培养国际会议上,Young Il-Lee报道,用γ射线照射盆栽水稻的花药,愈伤形成率比非照射植株的高得多。国际水稻研究所的科学家R.R.Aldemita和F.J.Zapata用电离辐射照射水稻种子,使之生长并取其穗进行花药培养,发现辐射对难处理种花药培养的影响与敏感种类花药培养的相反。γ射线辐射处理     

低温处理对水稻花药愈伤组织的诱导、分化的影响

近年来,花药培养工作在我.国广泛开展并取得一定的成果。但总的说来,培养水稻花粉植株的成功率还不高,这就直接影响花药培养单倍育种工作的效率,因此需进一步提高水稻绿苗分化率。目前一些单位采用低温处理各种作物的花药,以提高花药愈伤组织的诱导率。但具体做法和效果并不一致。胡忠等认为在10℃低温下(48—62小时)存放稻穗是暂时保存材料的有效方法,但并不能显著提高愈伤组织诱导率。钟华鑫等认为4～5℃低温对提高小麦花药愈伤组     

普通小麦单体的花药培养

近年来小麦花药培养研究资料表明,愈伤 组织诱导率与材料的遗传基础有很大关系［[1-3,8] Shimad：等〔7]用普通小麦中国春的A组染色体 的非整倍体类型进行花药培养,结果形成的愈 伤组织几乎全是由花丝产生的,并发现愈伤组 织诱导率最高的是双端体4A,其次是缺体4A, 其它材料的频率均较低。从而认为4A染色体 与愈伤组织诱导率有关。     

小麦花药培养对培养温度的反应II．不同基因型小麦花药的适宜培养温度

近年来小麦花药培养研究资料表明,愈伤 组织诱导率与材料的遗传基础有很大关系［[1-3,8] Shimad：等〔7]用普通小麦中国春的A组染色体 的非整倍体类型进行花药培养,结果形成的愈 伤组织几乎全是由花丝产生的,并发现愈伤组 织诱导率最高的是双端体4A,其次是缺体4A, 其它材料的频率均较低。从而认为4A染色体 与愈伤组织诱导率有关。     

小黑麦花药培养的研究

对八倍体小黑麦(Triticale)的花药培养条件进行了研究,得到如下结果:1.基本培养基N_6和 B_优于 MS。2.培养基中的蔗糖浓度在6—9%为最好。3.2,4-D 浓度用0.5—10毫克/升,一般采用2毫克/升。4.培养基中加入0.5%的活性炭有利于提高花粉愈伤组织的频率。5.花药在不加琼脂的液体培养基上漂浮培养,比在固化培养基上培养效果更好。6.光照或黑暗培养对花粉愈伤组织的形成并无显著地影响。7.在接种前将穗子插入 N_6培养基(无琼脂)中进行冷冻处理,和插入水中的对照相比花药的出愈率更高。     

Factors affecting the induction of pollen plants of intergeneric hybrids of Triticum aestivum X Triticum-Agropyron

Summary Experimental results showed that the use of potato extract as a basic component of culture medium had a promoting effect on producing calli in anther culture of the intergeneric hybrids of Triticum aestivum × Triticum-Agropyron (intermediate type). The induction frequencies of pollen callus on the Potato-II medium containing potato extract as the main component was much higher than that found on N₆ and W₅ media. The induction frequencies of pollen callus and green plantlets in four intergeneric hybrid material inoculated at the late-uninucleate pollen stage were all higher than those inoculated at the mid-uninucleate stage. Appropriate increases in culture temperature significantly increased pollen callus induction frequencies of the intergeneric hybrids. The genotype and physiological state of anther donor plants also influenced pollen callus and green plantlet induction frequencies.     

Anther cultures of tetraploid Solanum genotypes—the influence of gelling agents and correlations between incubation temperature and pollen germination temperature

Four tetraploid potato genotypes (194.10, 199.13, 201.5, 201.12) were examined in anther culture. The androgenic responses were in general high. Cv. 199.13 contributed with the best response, varying between 0.38 and 0.55 embryoids per anther. Gellan gum or potato starch were used as gelling agents in a double-layer medium. Anthers incubated on potato starch gave a higher embryo yield in the beginning of the culture period, compared to anthers cultivated on gellan gum. The number of embryoids per anther, however, was higher on gellan gum at the end of the culture period. Anther cultures of potato were incubated in two different temperatures (20 °C and 25 °C), and the highest embryo yield was obtained in 25 °C except for genotype 201.12 where no difference was found between the two temperatures. Experiments with pollen germination in various temperatures (10 °C and 20 °C) were correlated to anther culture experiments. Also in case of pollen germination, genotype 201.12 was temperature-independent, while germination was stimulated by higher temperatures in the other genotypes.     

Functional properties of ficoll and their influence on anther culture responses of wheat

The effects of ficoll in liquid culture media have been contradictory in previous reports. The objective of this study was to determine the functional properties of ficoll in potato 4 (P4) liquid induction medium and their influence on anther culture responses of wheat. Ficoll addition significantly (p0.01) reduced callus production from the anthers of spring wheat cv. Pavon 76. The reduction was directly related to the concentration of ficoll added within the range of 50 to 200 g l^-1 medium. Although the addition of ficoll significantly (p0.01) increased the percentage of regenerable calli and the ratio of green vs. albino plants, the final yield of green plants per 100 anthers was significantly lower. Consistent results also were obtained with four other spring wheat genotypes (Chris, Butte 86, WA 6916, and Edwall). Ficoll concentration affected the density, viscosity, and osmolality of the liquid media. The higher medium density caused by ficoll addition increased the percentage of floating calli, as well as the percentage of regenerable calli and the ratio of green vs. albino plants. However, the increased medium viscosity by ficoll addition significantly (p0.01) reduced callus production. Ficoll addition also increased medium osmolality, which affected callus production by interacting with the sugar concentration of the induction media. Using response functions, the estimated maltose concentration for maximum callus production was 105 g l^-1 for the standard P4 media, compared with 68 g l^-1 for the ficoll-containing P4 media. These results clearly demonstrate that ficoll addition to the liquid P4 induction medium containing high sucrose concentration (90 g l^-1) is deleterious to the maximum production of green plants from wheat anther culture.     

Effects of different gelling agents on the different stages of rice regeneration in two rice cultivars

Plant tissue culture technology offers a solution for meeting the increasing commercial demand on economically important plants such as rice, a widespread dietary staple. However, significant genotype-specific morphogenetic responses constitute a considerable on rice regeneration in plant biotechnology contexts. Aside from genotype dependency, the components of the nutrient media including gelling agents have an important impact on regeneration efficiency. The current study explores the effect of different gelling agents on various stages of rice regeneration in two Egyptian rice cultivars-Sakha104 and Giza178. Media solidified with varying concentrations of a variety of gelling agents (agar, bacto agar, gelrite and phytagel) were tested for their impact on the frequency of callus induction, shoot regeneration and rooting. The results indicated gellan gum (gelrite and phytagel) was superior to agar products (agar and bacto agar) for callus induction. By contrast, no significant differences were found between different gelling agents for shoot regeneration. Gellan gum and media solidified with bacto agar were found to lead to significantly higher root regeneration than agar. The Sakha104 cultivar showed better responses than Giza 178 for callus induction and similar performance to the Giza 178 cultivar for root regeneration irrespective of the gelling agent. This work provides insights into the impact of different gelling agents on the morphogenetic response of two rice cultivars and can be used to help maximize the frequency of rice regeneration.     

Elevated carbon supply altered hypericin and hyperforin contents of St. John's wort (Hypericum perforatum L. cv `New Stem') grown in bioreactors

For the high frequency selection of salt-tolerant doubled haploids (DHs) using rice anther culture, the efficiency of anther culture was investigated with different genotype, media condition and NaCl concentrations. The six F₁ hybrids obtained by backcross or three-way cross between indica and japonica differed in salt tolerance. The efficiencies of callus induction and plant regeneration was decreased by NaCl concentration and salt tolerance of donor variety, and those in japonicas were higher than those in indicas. The percentages of callus induction in Gyehwa 5 (japonica, tolerant) and IR61633-B-2-2-1 (japonica, sensitive) were 21.1 and 13.5% on agar medium containing 0.3% NaCl, respectively. The plant regeneration of callus derived from anther floating culture in liquid media was less than that on solid medium. In four F₁ hybrids, the frequencies of high salt-tolerant DHs were 21.4 and 8.9% in 0.3% NaCl medium and the control, respectively. The high frequency of salt-tolerant DHs could be selected in the callus induction medium (0.3% NaCl) and in the combinations crossed with salt-tolerant japonica as the third parent.     

基因型和培养条件对大麦花药培养的影响

不同基因型大麦(Hordeum vulgare)的花粉愈伤组织诱导率不同。带大麦黄花叶病抗性基因的品种。品系或F1杂种的诱导率(8.83—14.21%)高于不带抗性基因的材料(1.04—6.25%)。 MS基本培养基添加草2,4—D.1 mg/L,Kt0.1 mg／L,BA0.2mg／L,生物素0.1mg, 其诱导率(平均11.09%)高于MS添加2,4—D3mg／L和Kt0.1 mg／L的诱导率(6.33%)及MS添加2,4—D1mg／L 和Kt 0.1 mg／L的诱导率(8.21%)。接种后先15℃暗培养5天,再转入25℃暗培养,其产生愈仿组织的高峰期推迟2—4天,但诱导率却从对照的5.84%提高到11.59%;25℃暗培养与25℃光 — 暗交替培养,诱导率无显著差异。     

Anther Factor(s) in Barley Anther Culture

The effects of anther tissues were studied systematically on microspores forming multicellular units and furthermore on pollen callus formation in the anther culture of Hordeum vulgare (cv. Sabarlis). Anther productivity was found to be greatly enhanced by use of medium previously conditioned by anthers. In 15 experiments observed, anthers produced 26 times on average more calli in the conditioned medium than in control, in a few cases, even more than 80 times more calli formed. According to this, the authors supposed that cultured anthers released some components, anther factor (s) (AF), which is important to androgenesis in the culture. To achieve high yields of callus, culture was restricted to anthers which had been subpected to cold pretreatment. The temperature stress could not be replaced by the AF. However, for conditioning medium, anthers at binuclear stage were found to be more effective than the test anthers either with or without the pretreatment. Anthers from other 8 barley varieties were also effective for conditioning, as the difference of anther productivity still existed in the culture with conditioned medium between various genotypes tested. Anther response and callus yield were increased in both the culture of anthers at mid and late-uninuclear stage by use of conditioned medium. AF interacted synergistically with m-inositol. Cytological observation showed that AF increased apparently the formation of MPGs, while m-inositol mainly stimulated callus formation from MPGs. To some extent, the effect of exogenous hormone(s) could be replaced by AF. The anther response and pollen callus yield could be much enhanced by increasing anther inoculation density, which also raised the AF level in the culture. Thus, by use of the temperature stress prior to anther culture and culture of test anthers in conditioned medium with m-inositol, or at higher inoculation density, a very high production of pollen callus could be obtained in barley anther culture. For meeting the more specialized requirements of less responsive species or genopypes, the principles given here may be provide some basic information.     

In vitro induction of androgenic haploids in Safflower (Carthamus tinctorius L.)

The influence of culture medium on induction of androgenic calli was examined with five different basal media. MS medium was the most responsive in inducing callus. Differences in induction of calli among ten genotypes revealed that the most responsive genotype was a local cultivar, Mangira, with 48.6% anthers initiating callus formation. The influence of temperature pre-treatment (5°±1°C) for varying periods (0 to 15 days) on immature capitula prior to inoculation of anthers on the medium revealed that the percentage of anthers inducing callus increased till 3–5 days of pre-treatment. The effect of physiological conditions of anther donor plants grown in the field and in green houses on induction and re-differentiation have shown that the field grown anther donor plants exhibited optimum response. Shoot regeneration was observed on MS supplemented with BAP (2.0 mg/l) and NAA (0.5 mg/l) and rhizogenesis on MS (half-strength) medium, supplemented with NAA (0.1 mg/l) and 1% sucrose. Cytological studies of anther derived plants showed two ploidy levels, where the haploids were predominant (64%).     

Effect of induction medium pH and maltose concentration on in vitro androgenesis of hexaploid winter triticale and wheat

Low levels of in vitro androgenesis limit the utility of anther culture as a routine tool for the improvement of triticale. The objectives of this research were to determine the effect of induction medium modifications on the embryoid induction (EI) and green plant regeneration (GPR) of three hexaploid winter triticales and a hexaploid winter wheat. Medium modifications were factorial combinations of gelling agents, pH and maltose concentration. There was a significant difference in the response of wheat and triticales. An induction medium pH of 4.8 vs. 5.8 led to higher EI percentages in all cases and in Ficoll containing medium to a significantly higher GPR in the wheat, but it had no effect on the response of the triticales. Maltose at 0.26 M vs. 0.21 M increased the EI of both the triticales and the wheat but led to higher GPR only in the case of wheat. Averaged over genotypes, induction media with agar and Ficoll 400 were superior to the liquid form. In terms of GPR the wheat gave the highest response: 9.1%. The GPR percentages for the triticales ranged from 1.4 to 7.1. Genotype specificity must be overcome if anther culture is to be routinely used in diverse arrays of triticale germplasm.