Overcoming Self-Incompatibility of Brassica napus by Salt (NaC1) Spray

The results of studies from 1982 to 1989 confirm that self-incompatibility (SI) of B. napus can be effectively overcome by spraying solutions of 2 — 10 % table salt (NaCl) during the flowering period. The optimum salt concentration was found to be 5 %. Spraying onto both stigma and stamen is better than onto only one of them, in particular better than spraying only onto the stamen. When self-pollination occurred at intervals of 1 to 32 hours after spraying 5 % NaCl solution upon stigma and stamen, the compatibility indexes fall slightly; they decrease considerably after 72 and 120 hours, but still then they stay higher than without spraying. After spraying 5 % NaCl solution at intervals of 4, 5, 8 and 24 hours, respectively, the compatibility indexes after self-pollination are almost equal to that of bud-pollination; this treatment is effective even at intervals of 48 or 72 hours after selfing. In practice, spraying 5 % NaCl solution every 3 to 5 days during the flowering period is enough for satisfying seed set of SI lines under field conditions.     

Ga糯玉米自交系的配合力分析与评价

作者拟分析Ga糯玉米自交系主要农艺性状的配合力效应.并进行评价.利用不完全双列杂交NCⅡ设计,以3个经遗传改良的Ga糯玉米自交系为父本,与8个糯玉米自交系进行杂交.对24个杂交组合进行农艺性状鉴定.结果表明,父、母本各性状的一般配合力和特殊配合力效应均达极显著差异.Ga糯玉米自交系具有良好的配合力,其中,CM327的一般配合力效应比较高,其组配的杂交种在产量、穗长、行粒数等性状上具有明显优势,具有很好的杂优利用潜力.Ga糯玉米自交系的选育利用,有助于糯玉米种质的扩增与杂种优势的利用.     

The incompatibility system in Italian red chicory (Cichorium intybus L.)

As a result of an incompatibility mechanism which prevents both self-fertilization and intermating between plants with identical genotypes, inbreeding does not occur in Cichorium intybus. This self-incompatibility system complicates the production of inbred lines and the generation of F₁ hybrids in Italian red chicory. Histological observations on pollinated stigmas show that the incompatibility reaction in chicory is very rapid and either prevents pollen adhering to the stigmatic papillae or determines the arrest of pollen-tube growth on the stigmatic surface; incompatible pollen cannot reach the transmitting tissue of the style. Both histological and genetic analyses of F₁ progeny from a reciprocal cross between two unrelated plants suggest the occurrence of a sporophytic incompatibility system in Italian red chicory.     

Diversity of penicillarian millets (Pennisetum glaucum and P. purpureum) as for the compatibility between their gynoecia and pollens from some other Poaceae

Summary The compatibility between gynoecia of different penicillarian millets (Pennisetum glaucum and P. purpureum) and pollens from some other Poaceae was evaluated in order to determine whether different penicillarian pistils showed the same pistil-pollen interactions with a same non-penicillarian pollen and to determine whether compatibility was dependent on the genetic divergence or the degree of sympatric evolution of the mating partners. Ten pearl millet lines (P. glaucum subsp. glaucum), six wild pearl millet accessions (P. glaucum subsp. monodii) and one P. purpureum accession were pollinated with five other Pennisetum species: P. pedicellatum, P. polystachyon, P. schweinfurthii, P. squamulatum, P. ramosum, and with three species from other genera: Cenchrus ciliaris, Panicum maximum and Zea mays. Each male species was represented by a unique accession. Pollen grain germination on the stigmata and pollen tube growth in the gynoecia were monitored by means of fluorescence microscopy after aniline blue staining. Significant compatibility differences were observed between a given pollen and gynoecia from different P. glaucum accessions. But there was no evidence of compatibility differences between the three female taxonomic groups. The eight pollen parents can be classified into three groups according to their mean degree of compatibility with the different penicillarian gynoecia. P. ramosum, P. schweinfurthii and P. squamulatum showed a high compatibility: more than 50% of penicillarian gynoecia had pollen tubes at the micropyle, six hours after pollination. Zea mays, Cenchrus ciliaris and Panicum maximum showed a low compatibility: pollen tubes were arrested in the style. P. pedicellatum and P. polystachyon showed nil compatibility: few pollen grains germinated on the stigmata and very rare tubes reached the entry of the style, where they stopped. It must be noted that such a strong gametic barrier has been observed only with pollinator species sympatric to pearl millet.     

Identification and classification of S haplotypes in radish (Raphanus sativus)

Radish (Raphanus sativus L.) is a typical cross‐pollinated crop that exhibits obvious heterosis. Self‐incompatibility is an important character for F₁ hybrid breeding of radish. Knowledge of the S haplotypes of breeding lines is very important for breeders to avoid cross‐incompatibility of the parental lines. In the present study, the S haplotypes of 63 radish inbred lines, which were independently cultivated by our research group, were identified by PCR amplification, sequencing and BLAST analyses of the SRK and SLG genes. Finally, fifty‐four inbred lines were classified into 15 class I S haplotypes, including three new types, RsS‐38, RsS‐39 and RsS‐40. Additionally, three class II S haplotypes were identified in nine radish inbred lines. Partial SRK or SLG sequences were completed, such as RsS‐11 Lim (SRK‐S), RsS‐26 (SRK‐K), RsS‐5 Lim (SRK‐K and SRK‐S) and RsS‐9 (SRK‐K). The identified S haplotypes were verified with a cross‐pollination test, and RsS‐9 has weaker self‐incompatibility than other S haplotypes. These information will not only contribute to the production of hybrid seeds but also to the development of new self‐compatible inbred lines, which were advantageous of the production of maintain line and male line in CMS breeding system.     

植物离体嫁接的方法和研究进展(综述)

介绍了离体嫁接的特点和方法并且概括了其组织学和细胞学发育、同化物输导以及生化研究等方面的进展.     

Inbreeding depression in garden and glasshouse chrysanthemums: germination and survivorship

Summary Sixty-six chrysanthemum (Dendranthema grandiflora) inbred selections, noninbred cultivars and hybrids, and D. makinoi were the base populations from which up to three generations of inbreds were obtained using multiple plant descent. Each parent possessed pseudo-self compatibility (PSC), which allowed seed set following self pollination. Rapid-generation cycling (laboratory seed ripening to heart stage and subsequent embryo rescue) reduced generation time and minimized confounding maternal with zygotic inbreeding depression during post heart-stage seed development. Selection criteria were male/female fertility and PSC. Two stages of the life cycle were chosen to evaluate inbreeding depression: germination (seed development to germination) and survivorship (fertile individuals at anthesis). PSC was environmentally interactive and genotype dependent, causing variable levels of self seed set between and within populations and generations. By the end of the second generation, families from all noninbred cultivars, D. makinoi, and one F₁ hybrid were eliminated from the experiment due to self incompatibility and/or inbreeding depression. Post-germination inbreeding depression was severe in several advanced inbreds. Inbred progeny of most F₁ or F₂ hybrids expressed less or equal amounts of inbreeding depression compared to advanced inbreds. Linear regression coefficients for either germination or survivorship on percent homozygosity were negative. Correlation coefficients between percent germination and survivorship (as a percent of seed set) were highly significant for Minnesota inbreds (r=0.67, P0.002) and hybrids (r=0.67, P0.006). The correlation coefficient was higher when percent germination and survivorship (as a percent of germinated seedlings) were compared (r=0.95, P0.001).Abbreviations F Fisher's Coefficient of Inbreeding - IBD Inbreeding Depression - PSC Pseudo-self Compatibility - RGC Rapid Generation Cycle - SI Self Incompatibility     

植物核糖核酸酶与转基因工程雄性不育系研究进展

核糖核酸酶(Ribonuclease,RNase)的全名为聚核苷-#-寡核苷酸转移酶,它在植物体内分布广泛,是降解RNA的一类酶的总称。它与植物的衰老、抗逆、自交不亲和、植物雄性不育有密切关系。另一方面,当将从烟草、水稻中分离出的TA29和OsgB6等花药绒毡层及花粉特异启动子与核糖核酸酶基因(barnase)构建成嵌合基因,转移给正常油菜、烟草、番茄、小麦、水稻等植株时,又会产生雄性不育。因此,植物核糖核酸酶的研究日益受到人们的广泛关注。     

玉米异交不亲和基因Ga1-S的蛋白质组分析

为了研究玉米异交不亲和的蛋白表达机制,以玉米(Zea mays L.)异交不亲和基因Gal-S的一对近等基因系W22(GG)与w22(gg)为材料,组配自交(GG×GG)、正交(gg×GG)与反交(GG×gg) 3个组合。首先采用荧光显微技术, 观察比较了3个组合中花粉管在花丝中的生长过程;其次采用IEF/SDS-PAGE双向凝胶电泳与基质辅助激光解吸电离飞行时间质谱(MALDI-TOF-MS)技术,比较研究了授粉后10 h自交与反交母本W22(GG)花丝蛋白质组的特异表达差异。结果表明,授粉后10 h,自交与正交花粉管伸长可达花丝基部,而反交花丝基部未观察到花粉管;自交与反交母本W22(GG)花丝蛋白质组共检测到25个差异蛋白质点,其中15个在自交中特异表达,10个在反交中特异表达;通过MALDI-TOF-MS质谱测序和MASCOT序列分析,注释了12个蛋白质点;其中自交中特异表达的蛋白质点11、12、14和异交中特异表达的蛋白质点18、22、24可能与玉米异交不亲和密切相关。     

落叶松种间交配结实力变异和自交衰退的研究

落叶松种间杂交的结实率普遍较高，但不同种之间有一定差异，其中日本落叶松与兴安落叶松交配结实率最低。种内自由授粉和自交的对比试验显示，示粒种子产生的主要原因是自交。本文讨论了自交不孕无性系的可能利用途径。在不同交配组合下研究了华北落叶松捕捉花粉的过程，确定在传粉期花粉和雌性生殖器官存在一定的相互作用，但无特异性。传粉后约4周，珠心顶端破裂，分泌物进入珠孔道，并与珠被分泌物共同作用于花粉，使花粉向珠心移动。组织化学分析表明，从传粉到受精期间，蛋白质的分布发生区域性变化，传粉期蛋白质几乎分布于整个胚珠，而在受精期则主要集中在颈卵器之上的珠心组织中。初步确定在花粉萌发和受精期，华北落叶松中存在花粉识别与选择系统。