Plant regeneration from protoplasts of Iris germanica L.

Summary Protoplasts were isolated enzymatically from suspension cultures derived from embryogenic calli induced by leaf base culture of Iris germanica. In protoplast culture, the effects of glucose concentration, different sugars and combinations of 2,4-D and KIN on protoplast division and colony formation were examined. N6 medium supplemented with 0.1–1 mg/l 2,4-D, 1 mg/l KIN, 200mg/l casein hydrolysate, 250 mg/l proline, 0.2 M glucose and 20 g/l agarose was suitable for protoplast division and colony formation. When colonies formed were transferred onto hormone-free MS medium, many plantlets were regenerated through somatic embryogenesis. Thus, we could establish a plant regeneration system from protoplasts of I. germanica.Contribution from the Laboratory of Plant Breeding, Faculty of Agriculture, Miyazaki University, Japan, No. 95.     

甘薯胚性细胞悬浮培养系的建立

地甘薯胚性细胞悬浮增减系的进行了研究。将１２个基因的长约０．５ｍｍ的茎尖培养在含有０．２ｍｇ／Ｌ或２．０ｍｇ／Ｌ２，４－Ｄ的ＭＳ培养基上，形成了胚性愈伤组织。胚性愈伤组织的形成率因基因型和２，４－Ｄ深度不同而很大差异，为０－７５．７％。一方面，将胚性愈伤组织继续增减在含有２，４－Ｄ的ＭＳ培养基上，它们形成了处于各发育时期的体细胞胚。将具有体细胞胚的胚性愈伤组织转移到ＭＳ基本培养基上，体细胞胚发育成     

甘薯（Ipomoea batatas (L.) Lam.）及其近缘野生种原生质体的植株再生

对甘薯品种高系14号及其近缘野生种I.triloba L、和I.lacunosa L,进行原生质体植株再生研究。从离体培养植株的叶柄分离出原生质体,将其培养在含有0.05mg/L 2,4-D和0.5mg/L激动素(KT)的MS培养基中,从原生质体获得了高频率的愈伤组织。培养8-12周后,将直径达2—3mm的小愈伤组织转移到添加0.05mg/L 2,4-D的MS培养基上。转移3-6周后,将愈伤组织进一步转移到添加吲哚乙酸(IAA)和6-苄基嘌呤(BAP)的MS培养基上,一些愈伤组织再生出植株。未再生植株的愈伤组织进一步在MS基本培养基上培养,它们也再生出植株。本研究从I.triloba原生质体获得高频率的植株再生;首次从I.lacunosa原生质体再生出植株;从高系14号原生质体也再生出完整植株。     

Direct as well as indirect somatic embryogenesis from immature (unemerged) inflorescence of a minor millet Paspalum scrobiculatum L.

Somatic embryos differentiated directly on the rachis of immature inflorescences of Paspalum scrobiculatum L. cv. PSC 1 on culture to MS or N₆ medium supplemented with different concentrations (4.5–22.5 μM) of 2,4-dichlorophenoxyacetic acid (2,4-D). Direct embryogenesis on the rachis of inflorescence explants forms the first instance in graminaceous plants. Highest frequency of direct embryogenesis (34%and 30% cultures, respectively) was possible on N₆ medium supplemented with 4.5 μM of 2,4-D and MS medium fortified with9.0 μM of 2,4-D. Other tissues of the explant, floral-primordia, only after an initial phase of callusing differentiated into somatic embryos; indirect embryogenesis. Somatic embryogenesis, direct as well as indirect, was resolved by scanning electron microscopy. The somatic embryos germinated and developed into plantlets on regeneration medium. Interestingly, one week incubation of somatic embryos on activated charcoal (0.5%) fortified basal medium, supported high potential for ‘germination’ on transfer to charcoal-free basal medium. This beneficial effect of activated charcoal on regeneration of somatic embryos into plantlets is the first record in the Gramineae. This revised version was published online in July 2006 with corrections to the Cover Date.     

Intergeneric hybridization between Brassica species and Crambe abyssinica

A protocol for high frequency callus induction and plant regeneration from sunflower (Helianthus annuus L.) anthers is described. Different variables using Murashige & Skoog (MS) basal medium supplemented with 2.0 mg/l α-naphthaleneacetic acid (NAA) and 1.0 mg/l N₆-benzyladenine (BA) were tested for their ability to enhance the frequency of anther callusing and subsequent embryogenesis. Of these, agar concentration, sucrose concentration, carbohydrate source had significant effect on callusing, while differences due to incubation under dark vs light conditions, cold pretreatment of capitula for 1 to 6 days prior to anther inoculation and genotype on callusing were non-significant. However, all these factors exerted highly significant influence on embryogenesis when calli from the various media were transferred to medium supplemented with 0.1 mg/l NAA and 0.5 mg/l BA. With the procedure developed, callusing as high as 100% and embryo formation at a frequency of 44% was achieved. Although complete embryos were formed the frequency of their conversion to whole plantlets was low (14.3%). Hence, the embryogenic pathway was bypassed to obtain multiple shoots by transferring embryogenic calli with developing embryos to MS medium supplemented with 0.5 mg/l BA. Elongated shoots rooted on half-strength MS medium supplemented with 0.5 mg/l NAA. Cytological analysis of embryogenic callus and somatic embryos revealed haploids at a frequency of 30% while that of rooted plants showed haploid regenerants at a frequency of 8.3%. Nevertheless, the frequency of putative haploid plants could be enhanced through mass multiplication using nodal explants of the regenerants. This revised version was published online in August 2006 with corrections to the Cover Date.     

Indirect Organogenesis through Seedling-Derived Leaf Segments of <Emphasis Type="Italic">Ficus Religiosa</Emphasis> - a Multipurpose Woody Medicinal Plant

The aim of this study is to introduce the suitable protocol for indirect regeneration from seedling-derived leaf segment of Ficus religiosa. The leaf explant successfully produced callus on MS medium containing various concentrations of auxin in combination with BAP. The maximum callus induction (100%) was achieved in MS medium containing 0.5 mg/l 2,4-D plus 0.05 mg/l BAP and MS medium containing 1.5 mg/l NAA plus 0.15 mg/l BAP as well. MS medium consisting of 2,4-D produced yellow-brownish and friable callus (type I) while the yellowish and compact calli (type II) were obtained in MS medium consisting of NAA. On the other hand, MS medium supplemented with IBA formed greenish and compact calli (type Ш). The regeneration rate in type II callus was less than the type I, and there was no shoot induction observed on type Ш calli. MS medium supplemented with 1.5 mg/l BAP in combination with 0.15 mg/l IBA had the highest regeneration frequency (100%) and maximum shoot numbers (5.16) as well as shoot length (2.56 cm) in type I callus. A maximum of 93.33% root induction was observed in MS medium supplemented with 2.0 mg/l IBA plus 0.1mg/l NAA. The plantlets were successfully transferred to the greenhouse. This system could be utilized for large-scale multiplication of Ficus religiosa.     

Plant regeneration from callus culture in potato

Summary A procedure for plant regeneration from callus culture of potato, Solanum tuberosum L. is described. Calli were induced from 1–2 mm long shoot apices of potato cultivars Cara and A25/19 on half-strength Murashige and Skoog's medium (half-MS) supplemented with 3.2 mg IAA (indole-3-acetic acid), 1.0 mg kinetin (6-furfurylamino)purine], and 0.5 mg 2,4-D [2,4-dichlorophenoxy)acetic acid]/1. Sixty percent explants produced nodular calli on this medium within 30 days. Calli differentiated into shoot-primordia when subcultured on half-MS medium supplemented with 0.5 mg 2,4-D and 1.0 mg zeatin [6-(4-hydroxy-3-methybut-2 enylamino)amino purine]/1. Differentiated calli on half-MS medium without growth hormones produced complete plantlets which were cloned on the same medium and transferred into soil.     

花生原生质体分离与培养

以花生品种花育20为材料,探讨不同的酶液浓度、酶解时间及渗透压对花生原生质体分离的影响。结果表明:原生质体分离的适宜酶液配比是2%纤维素酶（Cellulase Onozuka RS）、0.2%果胶酶(Pectolyase Y-23),甘露醇渗透压调节剂的浓度为0.7 mol/L,暗处理10 h,叶片原生质体产量为4.86×105/ml,存活率75.6％,愈伤组织原生质体产量为4.97×105/ml,存活率75.4％。将分离的原生质体培养在添加1mg/LNAA和4mg/LBAP的改良MS液体培养基中。培养约2～3d后,细胞开始分裂。然后部分细胞继续分裂,并形成细胞团。培养5～6周后,将培养物转移到添加2mg/L2,4-D和3mg/LBAP的MS液体培养基（pH 5.8）中进行培养。7～8周后,将形成的直径为1～2mm的小愈伤组织转移到添加1mg/LNAA和5mg/LBAP的MS固体培养基上培养,小愈伤组织迅速生长。转移3～4周后,愈伤组织长至7～9mm。     

In vitro tetraploid induction via colchicine treatment from diploid somatic embryos in grapevine (Vitis vinifera L.)

A protocol for in vitro induction of tetraploids via colchicine-treated somatic embryos from immature zygotic embryos of diploid grapevine (Vitis vinifera L.) is reported. Embryogenic callus was initiated from immature zygotic embryos cultured on Nitsch and Nitsch (NN) medium supplemented with 1.0 mg/l 2,4-dichlorophenoxyacetic acid (2,4-D). The callus was transferred to NN medium containing 1.0 mg/l α-naphthalene acetic acid (NAA) and 0.5 mg/l benzyladenine (BA) to establish somatic embryogenesis. The vigorously growing globular embryos were selected and treated by 0, 10 or 20 mg/l colchicine for 1, 2 or 3 days, and then immediately transferred to NN medium supplemented with 0.03 mg/l NAA and 0.5 mg/l BA, for somatic embryo conversion and plant regeneration. The number of surviving embryos and regenerated plantlets following colchicine treatment decreased with increasing colchicine concentration and treatment time. Among 29 randomly investigated plantlets regenerated from colchicine-treated somatic embryos, five solid tetraploids (2n = 4× = 76) were identified by chromosome counting analysis; all others were diploid (2n = 2× = 38). Ploidy level of plant regenerated was also determined from leaves using flow cytometry. No chimeras with both 2C and 4C nuclei was produced from colchicine-treated somatic embryos. Significant differences in leaf stomata parameters were observed between diploid and induced tetraploid plantlets.     

Plant regeneration via organogenesis and somatic embryogenesis in callus cultures derived from mature zygotic embryos of leek (Allium ampeloprasum L.)

Summary A high frequency plant regeneration system via organogenesis and somatic embryogenesis was established with callus cultures derived from mature zygotic embryos of different leek genotypes (Allium ampeloprasum L.). Four different callus types with varying morphogenetic potential were obtained. Relatively high concentrations of the auxin 2,4-dichlorophenoxy-acetic acid reduced callus weight and subsequent shoot regeneration and primordia formation of the callus. Shoot regeneration and primordia formation of the callus decreased after prolonged subculture on media containing 2,4-dichlorophenoxy acetic acid. A callus growth period of six weeks on Murashige and Skoog medium with 0.25–0.5 mg l^-1 2,4-dichlorophenoxy acetic acid showed the highest rate of shoot regeneration after transfer of callus to regeneration medium with 1 mg l^-1 kinetin.Differences between leek genotypes in callus type, callus weight, shoot regeneration and primordia formation were observed. Histological observations showed that plant regeneration took place, both via the pathway of somatic embryogenesis and organogenesis.Abbreviation 2,4-D 2,4-dichlorophenoxy acetic acid - MS Murashige and Skoog (1962) medium     

High frequency plant-regeneration through direct shoot development and somatic embryogenesis from immature inflorescence cultures of finger millet (Eleusine coracana Gaertn)

Summary Plant regeneration from cultured immature inflorescence segments of Eleusine coracana was obtained by direct shoot development and somatic embryogenesis. Direct development of shoots from cultured inflorescence segments occurred on MS medium supplemented with 2,4-D in combination with zeatin. Inflorescences with well developed spikelets differentiated at a low frequency (<5%) from callus cultures initiated on media supplemented with 2,4-D in combination with zeatin or coconut water or picloram + kinetin. Somatic embryogenesis was also induced in callus cultures growing on MS + picloram + kinetin at the end of four passages. Supplementation of the media with different concentrations of sucrose showed 3% sucrose as the best concentration for plant differentiation from somatic embryos. The majority of the regenerated plants showed the diploid chromosome constitution in their root tips. The regenerants were in general shorter with an increased number of tillers compared to the control.Abbreviations CW Coconut water - 2,4-D 2,4-dichloro phenoxyacetic acid - Kn Kinetin - Z Zeatin     

表达bar基因的抗除草剂转基因甘薯的获得

用农杆菌介导法将bar基因导入甘薯主栽品种徐薯18的胚性悬浮细胞中,获得了抗除草剂的转基因植株.农杆菌菌株EHA105携带的双元载体pCAMBIA3300上含有bar基因.来自于徐薯18胚性悬浮细胞的直径为0.7～1.3 min的280个胚性细胞团用于遗传转化.共培养3 d后,首先在含有2 mg/L 2,4-D、100 mg/L Carb的液体MS培养基中培养1周,然后将胚性细胞团转移到添加2 mg/L 2,4-D、100 mg/L Carb 和0.3 mg/L PPT的固体MS培养基上进行选择培养.选择8周后,将获得的37个PPT抗性愈伤组织转移到添加1 mg/L ABA、100mg/L carb和0.3 mg/L PPT的固体MS培养基上,其中的34个愈伤组织诱导得到体细胞胚并发芽形成小植株,共获得了164株拟转基因植株.PCR分析表明,其中的123株为转基因植株.Southern blot和Northern blot分析表明,bar基因稳定整合到转基因植株的基因组中并正确表达.除草剂喷洒试验结果表明,转基因植株具有高度除草剂抗性.     

甘薯和Ipomoea lacunosa的种间体细胞杂种植株再生及鉴定

用ＰＥＧ融合法融合甘薯品种高系１４号和近缘野生种Ｉｐｏｍｏｅａ ｌａｃｕｎｏｓａ的原生质体，将融合原生质体培养在含有０．０５ｍｇ／Ｌ２，４－Ｄ和０．５ｍｇ／Ｌ ＫＴ的ＭＳ培养基上，愈伤组织迅速增殖。将其中的７０个愈伤组织培养在添加３．０ｍｇ／Ｌ ＢＡＰ的ＭＳ培养基上，并进一步培养在ＭＳ基本培养基上，获得９株再生植株。过氧化物酶同工酶、酯酶同工酶和ＲＡＰＤ分析表明，其中２株再生植株（ＫＬ１和ＫＬ３）     

Genotypic differences in organogenesis from callus of ten triticale lines

Summary Callus was obtained from immature excised embryos of triticale using MS medium supplemented with 3 mg/l 2,4-D and 1 mg/l kinetin. The presence of 2,4-D was essential for continued callus proliferation. Plantlets were induced from the calli by sub-culturing on medium either devoid of auxin or containing 0.1 mg/l 2,4-D. The capacity to produce callus and to form organs and plantlets differed markedly among the genotypes used. Lines also had distinct response to presence and absence of 2,4-D in the regeneration media. The callus of most triticale lines used differentiated into organs more readily on MS medium supplemented with 0.1 mg/l 2,4-D than on medium without growth regulators. Very high frequencies (up to 75%) of plantlet regeneration were observed in several of the triticale lines studied.     

新疆大叶紫花苜蓿(Medicago sativa.L)子叶、下胚轴、根的植株再生

随着植物抗逆性研究和植物转基因技术的发展，通过异源目的基因转化培育耐盐碱苜蓿品种的研究已引起人们的关注，植物受体高频再生体系的建立是异源转化高效的基础。选取新疆大叶紫花苜蓿种子萌发5~7d无菌苗的子叶、下胚轴及根为外植体，诱导愈伤培养基为MS+2,4-D 0.1~3.0 mg/L(8种不同水平)或MS+2,4-D 2.0 mg/L+ KT 0.01~0.5 mg/L(10种不同水平)，诱导芽培养基为MS+6-BA 0.5 mg/L+ NAA 0.05 mg/L，生根培养基为MS。结果表明，外植体在MS+2,4-D 2.0 mg/L+ KT 0.2 mg/L培养基中能够产生状态较好可再分化的愈伤组织，子叶、下胚轴、根的平均出愈率分别为93.1%、100%、100%。愈伤组织在MS+6-BA 0.5 mg/L+ NAA 0.05 mg/L培养基中培养40~80d中均可分化芽，子叶、下胚轴、根的芽平均分化率为50%、78%、50%，将2 cm以上的芽转入MS培养基中诱导生根，14d后，生根的小植株炼苗移入花土中，成活率达90%以上。子叶、下胚轴、根在该体系中均能获得再生植株，根也是一种较好的植株再生材料，以根为外植体进行植株再生的研究报道还较少。     

不同因素对橡胶树内珠被愈伤组织诱导和体细胞胚发生的影响

为了优化橡胶树内珠被植株再生体系,促进其次生体胚技术和转基因研究的发展,以橡胶树品种‘热研7-33-97’和‘热研88-13’的幼果内珠被为材料,进行不同因素对橡胶树内珠被愈伤组织诱导和体细胞胚发生的研究。在添加不同浓度的2,4-D,外加80 g/L蔗糖、50 mg/L椰子水、5.0 mg/L AgNO3和2.3 g/L phytagel的MH培养基上诱导愈伤组织的产生。结果表明,当培养基中不添加2,4-D时,2个品种均不能诱导出愈伤组织,随着2,4-D浓度的增加,其愈伤诱导率不断增加,达到4.0 mg/L水平时,诱导率均达到最大,分别为88.28%、86.67%。当浓度逐步升高至6.0 mg/L时,其诱导率又有所下降。愈伤诱导后,将其转移到添加了不同浓度NAA的改良MS基本培养基上。结果发现,0.2 mg/L的NAA浓度更有利于橡胶树‘热研7-33-97’内珠被子叶胚、喇叭胚、杯状胚和多叶胚等胚的产生,但子叶胚出胚率也仅达4.00%,而低于或高于此浓度均不利于体细胞胚的产生。     

High frequency of plant regeneration from anther culture in flax, Linum usitatissimum L.

The effects of induction medium compositions on flax anther culture were investigated in order to improve the efficiency of callus induction and plant regeneration. Anthers were inoculated onto the modified MS medium supplemented with five different combinations of plant growth regulators. The medium containing the combination of 2mg/l 2,4- dichlorophenoxy-acetic acid (2,4-D) and 1 mg/1 6-benzylaminopurine (BAP) produced a significantly higher number of calli forming shoots/100 responded anthers and a significant increase in overall efficiency of regeneration than the same basal medium containing 1 mg/1 a-naphthalene-acetic acid (NAA) and 2 mg/1 BAP (CK). Among the five levels of thiamin hydrochloride tested, the modified MS medium containing 10 mg/1 thiamin hydrochloride significantly increased the number of calli forming shoots/100 responded anthers and the overall efficiency of regeneration compared with the same basal medium containing 0.1 mg/1 thiamin hydrochloride. Maltose concentration had a significant effect on the percentage of anthers producing call, the number of calli forming shoots/100 responded anthers and the overall efficiency of regeneration. The medium containing 6% or 9% maltose produced the highest overall efficiency of regeneration among the five levels of maltose evaluated. Sucrose concentration significantly affected the number of calli forming shoots/100 responded anthers and the overall efficiency of regeneration, and dramatically affected the frequency of microspore-derived plants and the frequency of spontaneous chromosome doubling in microspore-derived plants. The efficiency of doubled haploid line production obtained in this study appears adequate for applied breeding programmes.     

Plant regeneration from embryo-callus culture in barley

Summary Plants were regenerated from callus cultures initiated from immature embryos of barley, Hordeum vulgare L. Immature embryos from seven diverse genotypes were cultured on modified Murashige and Skoog (MS) medium supplemented with 1.5 mg 2,4-D and 6.5 mg IAA/l. Of the 249 embryos cultured, 30% initiated callus within 8 days. Subculture of callus for 80 to 100 days on half-MS medium supplemented with 0.5 mg/l 2,4-D and 1.0 mg/l zeatin resulted in organogenesis. Culture of organogenic calli for 30 days on half-MS medium without growth regulators produced plants which originated mostly via multiple shoot formation. Callusing response of the tested genotypes ranged from zero to 44%; however, only 23% of the calli were regenerative. Regenerated plants included variants for chlorophyll deficiency, plant height, stem thickness, spike shape, pollen fertility, seed set and ploidy.     

新陆早42号体细胞胚发生和植株再生

 以新陆早33号为对照研究新疆主栽品种新陆早42号的体细胞胚胎发生。研究表明,所用4种激素组合均能有效诱导愈伤组织,但二者仅在经过IBA 1.0 mg·L^-1+KT 0.5 mg·L^-1和2,4-D 0.1 mg·L^-1+KT 0.1 mg·L^-1两种激素组合诱导初生愈伤后,才能胚胎发生。新陆早42号在IBA 1.0 mg·L^-1+KT 0.5 mg·L^-1培养基上46 d就开始胚胎发生;新陆早33号则不能直接胚胎发生,需继代到MSBP培养基上培养48 d才有胚胎发生。经2,4-D 0.1 mg·L^-1+KT 0.1 mg·L^-1组合培养的愈伤均需要继代到MSBP培养基上培养才能胚胎发生,新陆早42号和新陆早33号胚胎发生的最早时间分别是71 d和81 d。胚性愈伤在铺有滤纸的MSBF培养基上分化成胚并发育成再生植株。新陆早42号在140 d有根系发育良好的能嫁接植株（株高 7～8 cm）,而新陆早33需180 d。即成功建立了新陆早42号的再生体系,且其胚胎发生能力和再生能力均优于对照。     

刺五加体细胞胚再生体系的研究

以刺五加种子为外植体,采用固体培养筛选出最优培养基,并成功地诱导出体细胞胚获得再生植株,以此来建立一套成熟稳定的刺五加体细胞胚再生体系。试验结果表明, 最适宜的胚性愈伤组织诱导培养基为1/3MS+1.0 mg?L-12,4-D,其诱导率可达50%;胚性愈伤组织增殖的最适培养基为1/3MS+1.0 mg?L-12,4-D,其增殖倍数可达4.24倍;胚性愈伤组织在不添加任何植物生长调节物质的1/3MS培养基上培养,可促进体细胞胚的形成、萌发及植株转化率。添加10 g?L-1蔗糖时,体细胞胚的发芽率达到90%,植株转化率达到97.8%。