Production of interspecific hybrids between Alstroemeria pelegrina L. var. rosea and A. magenta Bayer by ovule culture

Interspecific hybrids were efficiently produced in the cross-incompatible combination between Alstroemeria pelegrina L. var. rosea and A. magenta Bayer by culturing immature ovules with placenta 7–14 days after pollination on 2 g/l Gelrite-solidified MS medium containing 3% (w/v)sucrose. The plants showed intermediate characteristics between the parents and their hybridity was confirmed by karyotype and DNA analyses. The mean number of chromosome association per PMC at metaphase I was 2.60I+6.70II, pollen stainability was20.8%, and they produced viable seeds after self-pollination. Furthermore, mature plants were obtained when the hybrids were backcrossed as male parents with both the parents. The backcross-progeny from A. pelegrina var. rosea × hybrids exhibited 3.8 to 79.7% pollen stainability and that from A. magenta × hybrids 78.8 to 98.3%. Almost all of these plants produced viable seeds after self-pollination, which implies that they can beutilized for breeding of novel cultivars of Alstroemeria. This revised version was published online in July 2006 with corrections to the Cover Date.     

Breeding of Polyploid Asparagus (Asparagus officinalis L.)

Asparagus is especially suitable for polyploidy breeding. The aim is to develop clone-based hybrid varieties, in particular male 4 × varieties. For this purpose, genetically divergent diploid idiotypes * * Idiotye (according to Reiger et al. 1976) is the sum of total hereditary determinants of an organism, consisting of its genotype (all determinants localized in the chromosomes) and its plasmotype (all determinants localized extra-chromosomally).
) are subjected to mitotic or meiotic polyploidization. In developing hybrid partners, special attention is paid to resistance in addition to yield and quality characters. Early diagnoses are applied in selection so as to shorten breeding times. Somaclonal variations may occur relatively often on in vitro propagation; these need to be eliminated. Triplex and quadruplex type males are suitable for paternal hybrid partners. Strong inbreeding depressions need to be avoided in their production.     

Production of interspecific hybrids between Glycine max and G. tomentella through embryo culture

Summary Interspecific hybrids have been obtained in an incompatible cross between Glycine max and G. tomentella through the in vitro culture of hybrid embryos. The percentage of successful pod setting in the crosses averaged 12.8% but there were marked differences depending on the soybean cultivar used as the female parent. Hybrid embryos at globular to heart stages were extracted from the embryo sac 15–25 days after pollination and cultured in vitro. Hybrid plants were successfully obtained by culturing the embryos on B5 medium supplemented with 0.1 mg/l IBA followed by culture on B5 medium supplemented with 0.1 mg/l TBA plus 0.25 mg/l 2-iP. The F1 plants resembled the wild male parent in growth form, but had an intermediate leaf shape between that of the parents.     

生物技术在芦笋育种中的应用

旨在为今后芦笋遗传育种工作提供参考和理论依据。本文综述了近几十年来国内外生物技术在芦笋育种研究中的应用主要进展,内容包括芦笋的组织培养、花药培养、小孢子培养、原生质体培养、多倍体诱导、分子标记技术及遗传转化等方面的研究,重点总结了生物技术在芦笋育种中发挥的作用及应用现状,并分析芦笋生物技术育种存在的问题。最后根据芦笋生物学特性与产业需求,探讨了未来芦笋生物技术育种工作的发展方向。     

Production of diploid and triploid interspecific hybrids between Lilium concolor and L. longiflorum by in vitro ovary slice culture

Successful hybridization between Lilium concolor and Lilium longiflorum has not been reported but ovary slice culture technique, after cut-style pollination has now been used to produce diploid and triploid interspecific hybrids between these species. Reciprocal crosses between diploid cultivars (2n= 2x= 24) were conducted. 5, 10, 15, 20, 25, 30, 35, 40, and 45 days after pollination (DAP), ovaries were sliced and cultured on a modified Murashige and Skoog (MS) medium without growth regulators and NH₄NO₃, supplemented with 6% sucrose, 50 mg/1 yeast extract and 0.25% gelrite at pH 6.3. For the L. concolor × L. longiflorum cross, embryo germination was found to be best at 20 DAP, while for the L. longiflorum × L. concolor at 25 DAP. After transfer to a MS (half-strength) medium supplemented with 1.5% sucrose, 0.25% gelrite and 0.2% active charcoal at pH 5.8, diploid and triploid hybrid plants were developed. All regenerated plants were identified as hybrids on the basis of karyotype and isozyme analyses. Ovary slice culture technique as a method of producing polyploids is discussed.     

中国芦笋栽培研究进展及展望

芦笋是一种食药兼用型蔬菜,中国芦笋栽培面积和出口量居世界首位。随着劳动力成本的增加,传统的粗放式栽培与劳动密集型生产模式制约了芦笋生产的发展。笔者从育苗、田间种植与管理、肥水运筹、病虫害防治、设施栽培模式等方面综述了中国芦笋栽培的研究进展。展望了中国芦笋产业的发展趋势,提出了新品种培育、无公害标准化栽培、机械化生产、延长产业链是芦笋产业持续发展的根本途径。     

Cytogenetics of interspecific hybrids in the genus Capsicum L.

Summary Crosses between a wild species C. chacoense and three cultivated species of chili pepper viz. C. annuum, C. frutescens and C. chinense yielded hybrids when C. chacoense was the seed parent but the reciprocal crosses were unsuccessful. C. chacoense × C. annuum F₁ hybrids were partly fertile and therefore an F₂ population could be raised; the other two F₁ hybrids were totally sterile. Chromosome pairing in the F₁ plants resulted largely in bivalents and a few multivalents and univalents. The genomes of the four species share large homologies and the role of chromosome structural changes in genome differentiation is suggested. Hybrid sterility is the major reproductive isolation mechanism.     

Development of breeding populations from interspecific hybrids between Trifolium repens L. and T. occidentale Coombe

Trifolium occidentale is a diploid wild relative of T. repens (white clover) with adaptation to dry, saline coastal habitats. Transfer of drought and salt‐tolerant adaptive traits to white clover could be potentially valuable if interspecific hybridization can be achieved efficiently and leads to fertile hybrid populations. To achieve hybridization, 4x plants of T. occidentale were generated. Efficient techniques for generation of 4x plants and their identification using dry pollen shape are described. Interspecific 4x F₁ plants were achieved without embryo rescue. F₂ populations and first backcross hybrids to white clover were also efficiently achieved. Although male and female fertility were lower than in white clover, they were adequate to produce large amounts of seed from small numbers of inflorescences. Thus, early generation interspecific hybrid prebreeding populations can be readily developed, opening the way for transfer of traits from T. occidentale to white clover.     

芦笋重要真菌病害研究进展

芦笋是重要的功能型蔬菜,芦笋真菌病害是威胁其生产的主要瓶颈之一,主要包括茎枯病、根腐病、枯萎病、褐斑病等。其中茎枯病是危害芦笋生产的世界性病害,特别是在中国,已成为生产中的突出问题。笔者简述了茎枯病等芦笋重要真菌病害在病原菌生物学特性、致病性、芦笋品种抗病性及病害关键防控技术等方面的研究进展,并展望了其发展趋势,认为今后应加强病原菌的致病和芦笋的抗病分子机制研究,为开展芦笋抗茎枯病分子育种提供基础。     

L-精氨酸对绿芦笋贮藏品质及生理生化特性的影响

以绿芦笋为试材,研究浓度为0.1 mmol/L的L-精氨酸对其在4℃贮藏过程中品质及生理生化特性的影响。结果表明,0.1 mmol/L的L-精氨酸浸泡30 min处理,能有效地降低绿芦笋的腐烂率、失重率和残渣率,减缓叶绿素的消耗及丙二醛(MDA)的生成,并通过有效抑制苯丙氨酸解氨酶(PAL)活性从而延缓了木质素的生成,提高绿芦笋的总抗氧化能力,说明0.1 mmol/L浓度的L-精氨酸处理能有效维持采后绿芦笋的品质,且L-精氨酸作为食品添加剂应用于果蔬保鲜具有安全性高的优势。     

芦笋SRAP反应体系优化及引物筛选

本研究以芦笋基因组总DNA为模板,通过对芦笋SRAP反应体系的重要参数进行优化,建立了一套适用于芦笋的SRAP反应体系:25μL的反应体系中,模板DNA量80ng、Mg2+浓度3.0mmol/L、上下游引物各0.2μmol/L、dNTPs0.3mmol/L、Taq DNA聚合酶1U以及1×Buffer。扩增程序为:94℃预变性3min;94℃30s、35℃30s、72℃1.5min,5个循环;然后退火温度提高到50℃,35个循环;最后72℃延伸10min。比较琼脂糖凝胶和变性聚丙烯酰胺凝胶电泳检测SRAP扩增产物的多态性,结果发现:6%变性聚丙烯酰胺凝胶电泳检测扩增产物比琼脂糖的效果好。利用该优化体系筛选引物,从256个SRAP引物组合中筛选出239个,它们具有扩增条带清晰、丰富、重复性好的优点,证明了此优化体系稳定可靠。     

The significance of andromonoecism for the breeding of Asparagus officinalis L. II

Summary Following a previous publication in this periodical (3), indicating the lines along which an entirely male asparagus variety can be obtained, the above article further discusses the difficulties to be overcome. The combination of andromonoecism and homozygosis for the male sex (andromonoecious MM-plants) is discussed in more detail. These plants, some hundreds of which are now in the possession of the Institute of Horticultural Plant Breeding, have the great advantage that they can be readily used to produce large numbers of MM plants. There is the danger, however, that andromonoecism is transmitted to the commercial seed of the male variety. Although the available figures do not yet provide certainty as to the genetic behaviour of andromonoecism, transmission is likely to depend on some dominant factors. Proceeding from this assumption we could already indicate in principle how to prevent andromonoecism in commercial seed.     

Chromosome pairing and fertility of interspecific hybrids between Trifolium repens L. and T. occidentale Coombe

Trifolium occidentale is a diploid wild relative with the potential to improve the drought and salt tolerances of white clover (Trifolium repens). Previous work has shown that it is possible to efficiently produce large T. repens × T. occidentale breeding populations using colchicine‐doubled (4×) T. occidentale. For effective introgression (backcross) breeding, it is also essential that interspecific chromosome pairing and recombination occur. In this study, it was apparent that chromosome pairing was occurring not only between T. occidentale and T. repens subgenomes, but also between the ancestral subgenomes of T. repens. Thus, interspecific hybridization has the potential for major genome recombination and opens the way for introgression of traits from T. occidentale into white clover.     

石刁柏幼胚胚状体发生与细胞学研究

以3个来自国外的石刁柏品种（C.IL,PURPLE和APOLLO）为试材,研究不同基因型以及培养基中添加2,4-D、KT、6-BA和NAA等生长物质对石刁柏幼胚胚状体发生的影响。结果表明,幼胚在MS＋2,4-D 1.0 mg/L＋KT 0.5mg/L＋6-BA 2.0 mg/L培养基中可直接诱导产生体细胞胚。降低2,4-D的浓度,将诱导产生的体细胞胚组织块继代培养2-3次可诱导产生出米黄色颗粒状的胚性愈伤组织,继而有胚状体的发生。胚性细胞继续分裂形成多细胞原胚,经球形胚、梨形胚、长形胚、子叶分化期到成熟胚,其发生的胚状体与单子叶合子胚形成具有相似的过程。     

石刁柏幼胚胚状体发生与细胞学研究

以3个来自国外的石刁柏品种(C.IL,PURPLE和APOLLO)为试材,研究不同基因型以及培养基中添加2,4-D、KT、6-BA和NAA等生长物质对石刁柏幼胚胚状体发生的影响.结果表明,幼胚在MS 2,4-D 1.0 mg/L KT 0.5 mg/L 6-BA 2.0 mg/L培养基中可直接诱导产生体细胞胚.降低2,4-D的浓度,将诱导产生的体细胞胚组织块继代培养2～3次可诱导产生出米黄色颗粒状的胚性愈伤组织,继而有胚状体的发生.胚性细胞继续分裂形成多细胞原胚,经球形胚、梨形胚、长形胚、子叶分化期到成熟胚,其发生的胚状体与单子叶合子胚形成具有相似的过程.     

Development of diploid and triploid interspecific hybrids between Lilium longiflorum and L. concolor by ovary slice culture

Ovary slice culture, after cut-style pollination, was used to develop interspecific hybrids between Lilium longiflorum and L. concolor. Reciprocal crosses between diploid cultivars (2n = 2x = 24) were carried out. On the days 30, 35, 40 and 45th after pollination (DAP), ovaries were sliced and cultured on a modified hormone-free Murashige-Skoog (M–S) medium without NH4NO3, supplemented with 6% sucrose, 50 mg/1 yeast extract and 0.25% gelrite at pH 6.3. For the L. longiflorum × L. concolor cross, ovule germination was found to be best at 30 DAP. After transfer to a M–S (half-strength) medium supplemented with 1.5% sucrose and 0.25% gelrite at pH 5.8, diploid and triploid hybrid plants were established. In contrast, ovules from the L. concolor × L. longiflorum cross did not germinate. The hybridity of the plantlets obtained was verified by karyotype and isozyme analysis. The importance of the ovary slice culture technique as a tool to develop new hybrids between incompatible lilly plants is discussed.     

Production and characterization of hybrids between Cajanus cajan × C. reticulatus var. grandifolius

Cajanus reticulatus var. grandifolius, endemic to Australia and a wild relative of the cultivated species, C. cajan, was successfully crossed with the latter as the female parent. The major wild species characters such as persistent stipules, long pod hairs, pod shattering, brown seeds with grey speckles, and presence of seed strophiole were dominant in the hybrid. For growth and branching habit, and leaflet, flower, pod, and seed size, the hybrid was intermediate between the parents. The meiotic cells of the hybrid were found to have quadrivalents, trivalents, univalents,and showed reduced chromosome pairing as revealed by the increased number of rod bivalents per cell at metaphase-I, and stickiness and precocious movement of chromosomes to poles in the second division. In comparison to the parents, the hybrid had fewer pods and seeds. However,these anomalies in the interspecific hybrid are not significant enough to preclude the gene transfer from C. reticulatus to the cultivated species through a sexual route. This revised version was published online in August 2006 with corrections to the Cover Date.     

芦笋单倍体染色体加倍技术研究

研究了芦笋单倍体染色体加倍的方法。在离体培养条件下,以秋水仙素为诱变剂,分别用浸泡法和培养基添加法处理芦笋单倍体幼苗的茎尖,比较了秋水仙素不同浓度、不同处理时间的诱导效果。结果表明,培养基添加法的诱导效果好于浸泡法,当在培养基中添加0.3%秋水仙素并处理7天时诱导效果最佳,染色体加倍频率与成活率分别可达82.50%和80%。加倍后的二倍体植株与单倍体植株相比,茎干变粗,气孔与保卫细胞增大,保卫细胞内的叶绿体数增多。