披碱草属植物的种间杂交和种质创新

披碱草属Elymus植物是小麦Triticum nestizum、大麦Hordeum vulgare的近缘属,同时蕴藏着丰富的优良基因,是改良小麦、大麦和黑麦Sacale cereale品种的优良基因资源。披碱草属植物也是草原和草甸的重要组成成分,具有极高的饲用价值和重要的水土保持功能,但国内在披碱草属植物资源和利用方面的研究与我国具有丰富的资源极不相称。现从国内外对披碱草属植物种间杂交利用方面进行论述,为充分开发利用我国丰富的披碱草属植物资源进行种质创新提供有价值的信息。     

应用胚珠切割及子房透明技术观察无融合生殖甜菜M14胚囊发育

介绍了一种快速简便观察分析无融合生殖甜菜胚囊发育过程的制片法。通过剥离胚珠,并对胚珠珠孔端进行再次切割和分离,经过固定和脱水,用冬青油整体透明及丁香油封片,在OLYMPUS—BX51型荧光显微镜下通过荧光技术观察发育中的胚囊产生自发荧光,可分辨出胚囊的内部结构。用FPA和4％戊二醛两种固定液效果不同．后者效果更佳。     

一种提取悬铃叶苎麻（ B. tricuspis （Hance） Marino）花序RNA的方法

应用改良CTAB法提取苎麻属野生种悬铃叶苎麻（Boehmeri．tricuspis（Hance）Marino）的花序RNA，通过1．2％琼脂糖凝胶电泳，测定分析260nm和280nm处的吸光值发现，应用该法提得的RNA完整性好，得率高；对其反转录产物进行AFLP分析表明，每一特定引物组合均能产生稳定清晰的条带，且在各引物间有差异。认为所提RNA符合分子生物学实验要求。另外，本文还对提取RNA过程中应注意的一些事项进行了讨论。     

人工创造植物无融合生殖的研究进展

对人工创造植物无融合生殖的各种途径进行了总结 ,对创造植物无融合生殖的方法进行了比较分析 ,认为植物体细胞杂交法是目前最好的选择。提出了两种用生物工程技术创造植物无融合生殖方法的设想 ,并对其应用前景进行了展望。     

中国野生牡丹自然繁殖特性研究

根据在甘肃、陕西、四川、云南和西藏等地的考察结果，论述了中国野生牡丹自然繁殖特性，将牡丹的繁殖划分为兼性营养繁殖和专性有性繁殖两种基本类型。前者包括紫牡丹（Ｐａｅｏｎｉａｄｅｌａｖａｙｉ）、黄牡丹（Ｐ．ｌｕｔｅａ）、狭叶牡丹（Ｐ．ｐｏｔａｎｉｎｉ）、矮牡丹（Ｐ．ｓｐｏｎｔａｎｅａ）和卵叶牡丹（Ｐ．ｑｕｉ），它们以多种形式的营养繁殖为主，种子繁殖为辅；后者包括大花黄牡丹（Ｐ．ｌｕｔｅａｖａｒ．ｌｕｄｌｏｗｉ）、四川牡丹（Ｐ．ｄｅｃｏｍｐｏｓｉｔａ）、紫斑牡丹（Ｐ．ｒｏｃｋｉ）和杨山牡丹（Ｐ．ｏｓｔｉ），种子繁殖是其唯一的繁殖途径。讨论了繁殖特性在野生牡丹种质资源保护和利用中的重要意义。     

Review of Pennisetum section Brevivalvula (Poaceae)

Section Brevivalvula is one of five sections in the large tropical grass genus Pennisetum. It belongs to the tertiary genepool of P. glaucum (L.) R. Br., pearl millet, and consists of six morphological taxa: P. atrichum Stapf & Hubb., P. hordeoides (Lam.) Steud., P. pedicellatum Trin., P. polystachion (L.) Schult., P. setosum (Swartz) L. Rich. and P. subangustum (Schum.) Stapf & Hubb., which together form a polyploid and agamic complex. Four euploid (x = 9) and twelve aneuploid chromosome levels have been found till now; the polyploids are apomictic, while diploid populations of P. polystachion and P. subangustum are considered sexual. This revised version was published online in July 2006 with corrections to the Cover Date.     

Breeding for apomixis in potato: Pursuing a utopian scheme

Summary Apomictic propagation in potato holds a great promise for the new technology of growing potatoes from botanical seeds in stead of tubers. It is explained that apomixis results from the combination of abnormal meiosis, abnormal fertilization and parthenogenesis.An ideal scheme is given for growing potatoes from true seeds. This scheme remains utopian when autonomous apomixis is not available. Autonomous apomixis occurs when the reduction division is lacking (no gene recombination, no reduction of chromosome number) and the resulting 2n egg cell develops parthenogenetically without fertilization of the central nucleus. The first best approach is pseudogamous apomixis, which differs from autonomous apomixis in the necessity of fertilization of the central nucleus. Second best is the parthenogenetic development of 2n eggs, since these have originated through an abnormal type of reduction division. This type is characterized by the lack of formation of a reduction cell wall and fusion of the two spindles at metaphase II of meiosis (first division restitution).Apomixis in the narrow sense, either pseudogamous or autonomous, is defined. It has not been found in potato species or species hybrids. On the basis of our knowledge about characteristic features of existing apomictic species, about genetics and evolution of apomixis and about the occurrence of particular elements of apomixis in potato the possibility of introducing apomixis into potato from existing elements is discussed along with methods to induce missing elements. Some tentative approaches are suggested which in the long run may lead to the detection of potato genotypes with apomictic propagation.Edited version of a paper presented at the 19th Planning Conference of the International Potato Center (CIP) in Manila, Philippines in September 1979 on production of potatoes from true seed. Published with the consent of CIP.     

Regeneration and somaclonal variation in apomictic Paspalum dilatatum Poir

Summary In an attempt to incorporate variation into a uniform obligate apomict, plants of apomictic common dallisgrass, Paspalum dilatatum Poir., were regenerated from callus derived from immature inflorescences. Plants developed through both organogenesis and embryogenesis. A total of 682 regenerants were produced and more than 400 were transplanted into a field nursery and screened for somaclonal variation. Eventually 20 regenerants were selected, increased, and planted into a replicated nursery along with normal common dallisgrass. The characteristics examined were maturity date, plant height, number of racemes per inflorescence, number of spikelets per raceme, pubescence, stigma and anther color, ergot resistance, seed germination, seed set, pollen stainability, method of reproduction, and chromosome number. There were differences among the regenerants and between them and common dallisgrass for all traits except chromosome number, stigma and anther color, and ergot resistance. One of the more important regenerants had significantly higher seed set than common dallisgrass. All regenerants reproduced by aposporous apomixis but some exhibited a high degree of abortion while others had more aposporous embryo sacs per ovule than common dallisgrass. These findings demonstrate that common dallisgrass can be regenerated through tissue culture and that somaclonal variation is expressed in some of the regenerants, even though some of the altered traits are deleterious.     

Pollen donor impact on progenies of pseudogamous blackberries (Rubus subgen. Rubus)

A series of intra- and interspecific crosses in Rubus was evaluated with DNA markers to assess the proportion of apomictically vs. sexually derived progeny plants. The species were well separated from each other with these markers and the interspecific hybrids were easy to ascertain. Ten plants each were derived by selfing of R. hartmanni, R. polyanthemus and R. vestitus, and evaluated with RFLP. Of these plants, only one R. hartmanni plant appeared to be sexually derived, whereas the remainder appeared to have arisen by apomixis. Between 10 and 19 progeny plants, derived by open pollination of R. Hartmanni, R. infestus, R. laciniatus and R. vestitus, respectively (total of 63plants), were evaluated with RFLP. Of these, 6 plants (approx. 10%) showed as lightly deviating band pattern, which may indicate sexual seed set but could also result from experimental artefacts. The three species combinations 1) R. hartmanni and R. sprengelii, 2) R. infestus and R. vestitus, and 3)R. laciniatus and R. polyanthemus were cross-pollinated reciprocally and the resulting progenies evaluated with RAPD (combinations 1 and 2)and leaf shape (combination 3). Combination1 produced 20% (3 out of 15 progenies)sexually derived progenies, combination 2produced 100% (26 progenies) and combination 3 produced 64% (16 out of 26progenies), respectively. The hybrid progenies appeared to have been derived through pollination of unreduced as well as reduced egg cells. The ability to produce interspecific hybrid progenies is most probably dependent upon the species combination. This revised version was published online in July 2006 with corrections to the Cover Date.