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71.
Two new loci for hybrid sterility in cultivated rice (Oryza sativa L.) 总被引:17,自引:0,他引:17
J. Wan Y. Yamaguchi H. Kato H. Ikehashi 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,92(2):183-190
Female gamete abortion in Indica-Japonica crosses of rice was earlier identified to be due to an allelic interaction at the S-5 locus on chromosome 6. Recently, in other crosses of rice, similar allelic interactions were found at loci designated as S-7 and S-8, located on chromosomes 7 and 6 respectively. All of them are independent of each other. At the S-5 locus, Indica and Japonica rice have S-5
i
and S-5
j
alleles respectively and Javanicas, such as Ketan Nangka, have a neutral allele S-5
n
.The S-5
i
/S-5
j
genotype is semi-sterile due to partial abortion of female gametes carrying S-5
j
, but both the S-5
n
/S-5
i
and S-5
n
/S-5
j
genotypes are fertile. The S-5
n
allele is thus a wide-compatibility gene (WCG), and parents homozygous for this allele are called wide-compatible varieties (WCV). Such parents when crossed with Indica or Japonica varieties do not show F1 hybrid sterility. Wide-compatible parents have been used to overcome sterility barriers in crosses between Indica and Japonica rice. However, a Javanica variety, Ketan Nangka (WCV), showed typical hybrid sterility when crossed to the Indian varieties N22 and Jaya. Further, Dular, another WCV from India, showed typical hybrid sterility when crossed to an IRRI line, IR2061-628-1-6-4-3(IR2061-628). By genetic analyses using isozyme markers, a new locus causing hybrid sterility in crosses between Ketan Nangka and the Indicas was located near isozyme loci Est-1 and Mal-1 on chromosome 4, and was designated as S-9. Another new locus for hybrid sterility in the crosses between Dular and the IR2061-628 was identified and was found linked to four isozyme loci, Sdh-1, Pox-2, Acp-1 and Acp-2, on chromosome 12. It was designated as S-15. On the basis of allelic interactions causing female-gamete abortion, two alleles were found at S-9, S-9
kn
in Ketan Nangka and S-9
i
in N22 and Jaya. In the heterozygote, S-9
kn
/S-9
i
, which was semisterile, female gametes carrying S-9
kn
were aborted. The hybrid of Dular and IR2061-628, with a genetic constitution of S-15
Du
/S-15
i
, was semi-sterile and the female gametes carrying S-15
Du
were aborted. A Japonica tester variety, Akihikari, and an Indica variety, IR36, were found to have neutral alleles, S-9
nand S-15
n, at these loci, in addition to S-7
nand at S-7. The accumulation of three neutral alleles into a breeding line should help solve the hybrid sterility problem in wide crosses of rice. 相似文献
72.
Ronald J. Prokopy Ratana Poramarcom Manon Sutantawong Ranu Dokmaihom Jorge Hendrichs 《Journal of Insect Behavior》1996,9(1):133-142
Oriental fruit flies,Bactrocera dorsalis, cultured in the laboratory for six generations, were released when 12–14 days old in an orchard of nonfruiting host trees that were furnished with either food and water, nonpunctured host fruit, punctured host fruit, or no resources. Nearly all flies of both sexes, all sexual behavior of males, and all mating pairs were observed on trees with fruit. Moreover, on trees with fruit, nearly all flies of both sexes, nearly all sexual behavior of males, and nearly all mating pairs occurred on the fruit itself rather than on the foliage or branches. In a subsequent test, both sexes were found to be strongly attracted to the odor of host fruit. For a polyphagous species of a tropical tephritid, these findings are the first to show a high level of male aggregation and a high amount of male sexual behavior on the fruit of host trees. Findings are discussed in relation to current knowledge of tephritid mating behavior. An additional quality-control test for laboratory cultured males used in the sterile insect technique of fly management is recommended. 相似文献
73.
一个恢复力受单基因控制的水稻CMS育性回复突变体 总被引:3,自引:0,他引:3
利用 ̄(60)Co-γ射线对具有印尼水田谷细胞质的籼稻细胞质雄性不育系Ⅱ-32A干种子进行诱变处理,获得了一育性回复突变体T24。育性基因未纯合的突变体分离出可育株和完全不育株,比例为3∶1;其与Ⅱ-32A和珍汕97A测交,F1代分离出1∶1的可育株和不育株。育性稳定株系与Ⅱ-32A和珍汕97A杂交,F2分离成3∶1的可育株和不育株。表明其育性回复是由一对基因显性突变所致。这一突变体对不育系的育性恢复机制不同于明恢63、20964等恢复系,后者表现为两对显性恢复基因作用。未观察到T24与亲本Ⅱ-32A除育性以外的其他性状的差异,因而两者构成育性恢复基因的近等基因系。本文还对不育系育性回复类型和T24的理论意义与育种价值进行了讨论。 相似文献
74.
Summary Selection favouring an outcrossing plant's ability to sire seeds generally promotes floral characters that increase (1) the frequency of pollinator visits, (2) the number of pollen grains dispersed to other plants by each pollinator and (3) the probability of a pollen grain successfully fertilizing an ovule after reaching a stigma. Flowers influence pollen dispersal and fertilization probabilities by determining the pattern of pollen removal during a series of visits (dispensing schedule). We model male reproductive success to identify optimal dispensing schedules, which characteristically involve monotonic increases in the proportion of remaining pollen removed during successive visits. These schedules balance the benefits of restricted removal, which counteracts the diminishing returns associated with animal pollination (e.g. pollinator grooming, local mate competition), with the advantages of increased removal to avoid time-dependent losses in fertilization ability (e.g. pollen precedence, declining viability). Because pollinator availability mediates this balance, the most effective dispensing schedule allows dynamic adjustment of removal to the prevailing frequency of visits experienced by individual plants. As an example of such dynamic removal we demonstrate that the dispensing mechanism ofLupinus sericeus flowers allows facultative adjustment of removal to the interval between visits. Because optimal control of pollen removal can increase a plant's mating opportunities by an order of magnitude, dispensing mechanisms should be a common component of floral design. 相似文献
75.
We produced three monoclonal antibodies, SG1, SG2 and SG3, specific for human seminal -glutamyltransferase when characterized by enzyme-linked immunosorbent assay and immunoblotting. Seminal -glutamyltransferase was localized, by immunostaining, to the epithelial cells of the ductus epididymidis, seminal vesicle and prostate gland with SG1, those of the prostate gland with SG2, and those of the seminal vesicle with SG3. Rabbit polyclonal anti-seminal -glutamyltransferase serum reacted with the proximal convolution of the kidney and the bile capillaries of the liver, and with the epithelial cells of the reproductive organs. However, immunoreactivity was not observed in the kidney or liver with the monoclonal antibodies. Thus, these monoclonal antibodies are probably all specific to seminal -glutamyltransferase but recognize different epitopes. 相似文献
76.
A. Mukhopadhyay N. Arumugam A. K. Pradhan H. N. Murthy B. S. Yadav Y. S. Sodhi D. Pental 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1994,89(1):19-25
Oilseed crop Brassica carinata BBCC is a natural allotetraploid of diploid species B. nigra BB and B. oleracea CC. To transfer the nuclear and organelle genes in a concerted manner from an alien species, B. tournefortii TT, to B. carinata, we produced somatic hybrids with genomic configuration TCBB using B. nigra and B. oleracea stocks that carried selectable marker genes. B. tournefortii TT was sexually crossed with hygromycin-resistant B. oleracea CC. Protoplasts isolated from shoot cultures of hygromycin-resistant F1 hybrids of B. tournefortiixB. oleracea TC were fused with protoplasts of kanamycin-resistant B. nigra BB. In two different fusion experiments 80 colonies were obtained through selection on media containing both hygromycin and kanamycin. Of these, 39 colonies regenerated into plants. Analysis of 15 regenerants by random amplified polymorphic DNA (RAPD) markers showed the presence of all three genomes, thereby confirming these to be true hybrids. Restriction fragment length polymorphism (RFLP) analysis of organelle genomes with heterologous chloroplast (cp)and mitochondrial (mt) DNA probes showed that the chloroplast genome was inherited from either of the two parents while mitochondrial genomes predominantly showed novel configurations due to either rearrangements or intergenomic recombinations. We anticipate that the TCBB genomic configuration will provide a more conducive situation for recombination between the T and C genomes during meiosis than the TTCCBB or TCCBB type configurations that are usually produced for alien gene transfer. The agronomic aim of producing TCBB hybrids is to transfer mitochondrial genes conferring cytoplasmic male sterility and nuclear genes for fertility restoration from B. tournefortii to B. carinata. 相似文献
77.
We isolated and sequenced Ha hsp 17.9, a DNA complementary (cDNA) of dry-seed stored mRNA that encodes a low-molecular-weight heat-shock protein (LMW HSP). Sequence analysis identified Ha hsp17.9, and the previously reported Ha hsp17.6, as cDNAs encoding proteins (HSP17.6 and HSP17.9) which belong to different families of cytoplasmic LMW HSPs. Using specific antibodies we observed differential expression of both proteins during zygotic embryogenesis under controlled environment, and a remarkable persistence of these LMW HSPs during germination. Immuno-blot analysis of HSP17.9 proteins in two-dimensional gels revealed that the polypeptides expressed in embryos were indistinguishable from LMW HSPs expressed in vegetative tissues in response to water deficit; but they appeared different from homologeous proteins expressed in response to thermal-stress. Tissue-print immunolocalization experiments showed that HSP17.9 and HSP17.6 were homogeneously distributed in every tissue of desiccation-tolerant dry seeds and young seedlings under non-stress conditions. These results demonstrate developmental regulation of specific, cytoplasmic, plant LMW HSPs, suggesting also their involvement in water-stress tolerance. 相似文献
78.
79.
Sporophytes were aseptically obtained by co-culture of female and male gametophytes derived from two types of spores (megaspores and microspores) of the heterosporous fernSalvinia natans All. Protoplasts isolated enzymatically from juvenile leaflets of sporophytes were cultured in a 1/10 Murashige and Skoog's medium containing 2.2 M naphthalene acetic acid, 2.2 M 6-benzyl-aminopurine, 0.35 M mannitol, and 0.05 M sucrose. Cell division took place within 6 days of culture, and cell-clusters composed of 9–10 cells were observed after 30 days of culture.Abbreviations BA
6-benzyl-aminopurine
- MS
Murashige and Skoog
- NAA
naphthaleneacetic acid 相似文献
80.