Home About us Contact
|
Home About us Contact | ||
|
|
||
Single Recessive Gene (single + recessive_gene)
Selected AbstractsInheritance of resistance against biotype 2 of the Asian rice gall midge, Orseolia oryzaeENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 1 2000J. Pani Abstract The inheritance of resistance in the rice cultivars Phalguna, ARC5984, ARC 5158, Veluthacheera, and T1477 to the Asian rice gall midge biotype 2 was studied under both natural and artificial infestation conditions against the susceptible cultivars Jaya and IR20. A single recessive gene in Veluthacheera and two recessive complementary genes in T1477 control resistance. Phalguna and ARC5984 possess a single dominant gene while ARC5158 has a single dominant and a single recessive gene for resistance. Allelism studies showed that genes for resistance in Veluthacheera and T1477 are allelic but non-allelic to the resistance genes in Phalguna and ARC5984, which are allelic to each other. Genes for resistance in ARC5158 are allelic to resistance genes of the other four donors. There was no cytoplasmic inhibition of resistance by the susceptible parents. [source] Genetic Analysis and Molecular Mapping of a Rolling Leaf Mutation Gene in RiceJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 12 2007Ji-Cai Yi Abstract A rice mutant with rolling leaf, namely ,- rl, was obtained from M2 progenies of a native indica rice stable strain Qinghuazhan (QHZ) from mutagenesis of dry seeds by ,-rays. Genetic analysis using the F2 population from a cross between this mutant and QHZ indicated the mutation was controlled by a single recessive gene. In order to map the locus for this mutation, another F2 population with 601 rolling leaf plants was constructed from a cross between ,- rl and a japonica cultivar 02428. After primary mapping with SSR (simple sequence repeats) markers, the mutated locus was located at the short arm of chromosome 3, flanked by RM6829 and RM3126. A number of SSR, InDel (insertion/deletion) and SNP (single nucleotide polymorphism) markers within this region were further developed for fine mapping. Finally, two markers, SNP121679 and InDel422395, were identified to be flanked to this locus with genetic distances of 0.08 cM and 0.17 cM respectively, and two SNP markers, SNP75346 and SNP110263, were found to be co-segregated with this locus. These results suggested that this locus was distinguished from all loci for the rolling leaf mutation in rice reported so far, and thus renamed rl10(t). By searching the rice genome database with closely linked markers using BLAST programs, an e -physical map covering rl10(t) locus spanning about a 50 kb region was constructed. Expression analysis of the genes predicted in this region showed that a gene encoding putative flavin-containing monooxygenase (FMO) was silenced in ,- rl, thus this is the most likely candidate responsible for the rolling leaf mutation. [source] Identification and Mapping of Two New Genes Conferring Resistance to Powdery Mildew from Aegilops tauschii (Coss.) SchmalJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 10 2006Xiao-Li Sun Abstract Two powdery mildew resistance genes were identified from Aegilops tauschii accessions Y201 and Y212 and mapped using two different F2 populations derived from the crosses between susceptible accession Y2272 and Y201, and susceptible accession Y2263 and Y212. Genetic analysis of resistance to powdery mildew indicated that the resistance of Y201 was controlled by a single dominant gene, whereas the resistance of Y212 was controlled by a single recessive gene. We have temporarily designated these genes as PmY201 and PmY212, respectively. By bulk segregation analysis, six microsatellite markers including Xgwm174, cfd26, cfd57, cfd102, Xgwm583 and Xgwm639 were found to be linked to PmY201 with genetic distances of 5.2, 7.7, 9.6, 12.5, 20.2 and 22.1 cM, respectively. Five SSR markers, including cfd57, Xgwm182, cfd7, cfd102, and cfd12, were found to be linked to PmY212 with distances of 5.6, 7.2, 11.5, 14.7, and 18.5 cM, respectively. According to the locations of the linked markers, the two resistance genes were located in the 5DL region. Based on the chromosomal locations and the resistance patterns of the two genes, we propose that PmY201 and PmY212 are two novel powdery mildew resistance genes, and are suitable for marker-assisted selection. (Managing editor: Ya-Qin Han) [source] Genetic analysis and gene mapping of a rice recessive male sterile mutantPLANT BREEDING, Issue 3 2010J. B. Chen With 3 figures and 2 tables Abstract Male sterility of rice is one of the major genetic tools used for hybrid rice production. In this study, a spontaneous male sterile mutant, SC-ms-2, was obtained from the F4 progeny of the cross D 297B × Changfeng B. Microscopic observation revealed that the microspores were developed abnormally and the tapetum cells were incrassated during microsporogenesis. Genetic analysis indicated that male sterility of SC-ms-2 was controlled by a single recessive gene. By using bulked segregant analysis on two F2 populations developed from crossing SC-ms-2 with Hua B and ,Nipponbare', this gene was finely mapped between two simple sequence repeat (SSR) markers on chromosome 9, RM24451 and RM7048, with genetic distance of 0.3 cM and 0.6 cM respectively, and the approximate physical distance was 172 kb. Our results showed that this gene was distinguished from all the other male sterility genes in rice reported and it was designated ms92(t), temporally. Moreover, candidate genes in the region of 172kb, including the rice homologue to the Arabidopsis MALE STERILITY1 (MS1) gene, were surveyed and discussed. [source] Mutagenic induction of double-podding trait in different genotypes of chickpea and their characterization by STMS markerPLANT BREEDING, Issue 1 2010H. Ali With 1 figure and 2 tables Abstract A gene that confers double-podding in chickpea is considered to be important for breeding higher yielding cultivars. Double-podded mutants were produced from five desi- and four kabuli-type chickpea genotypes through induced mutations and stabilty was checked up to M13 generation. Desi-type produced higher number of mutants as compared with kabuli-type. The inheritance studies in induced mutants of six genotypes showed that the double-podded trait was governed by single recessive gene. Different genotypes and their double-podded mutants were also characterized through sequence-tagged microsatellite site marker, TA-80. Allelic variations were found in single-podded genotypes and eight different alleles were identified, while for double-poddedness no allelic variants were found in all the analysed mutants. Addition of bases in the double-podded mutants showed that there might be involvement of transposable elements in the production of double-podded mutants through mutagens. [source] Genetic analysis of seedling resistance to Stagonospora nodorum blotch in selected tetraploid and hexaploid wheat genotypesPLANT BREEDING, Issue 2 2009P. K. Singh Abstract Stagonospora nodorum blotch (SNB), caused by Phaeosphaeria nodorum, is a major component of the leaf-spotting disease complex of wheat (Triticum aestivum L.) in the northern Great Plains of North America. This study was conducted, under controlled environmental conditions, to determine the inheritance of resistance to SNB in a diverse set of hexaploid and tetraploid wheat genotypes and to decipher the genic/allelic relationship among the resistance gene(s). Plants were inoculated at the two to three-leaf stages with a spore suspension of P. nodorum isolate Kelvington-SK and disease reaction was assessed 8 days after inoculation based on a lesion-type scale. Tests of the F1 and F2 generations and of F2 : 3 or F2 : 5 families indicated that a single recessive gene controlled resistance to SNB in both hexaploid and tetraploid resistance sources. Lack of segregation in intra-specific and inter-specific crosses between the hexaploid and the tetraploid resistant genotypes, indicated that these genetically diverse sources of resistance possess the same gene for resistance to SNB. Results of this study suggest that the wheat- P. nodorum interaction may follow the toxin model of the gene-for-gene hypothesis. [source] Evaluation of common wheat cultivars for tan spot resistance and chromosomal location of a resistance gene in the cultivar ,Salamouni'PLANT BREEDING, Issue 4 2006W. Tadesse Abstract A total of 50 wheat (Triticum aestivum L.) cultivars were evaluated for resistance to tan spot, using Pyrenophora tritici-repentis race 1 and race 5 isolates. The cultivars ,Salamouni', ,Red Chief', ,Dashen', ,Empire' and ,Armada' were resistant to isolate ASC1a (race 1), whereas 76% of the cultivars were susceptible. Chi-squared analysis of the F2 segregation data of hybrids between 20 monosomic lines of the wheat cultivar ,Chinese Spring' and the resistant cultivar ,Salamouni' revealed that tan spot resistance in ,Salamouni' was controlled by a single recessive gene located on chromosome 3A. This gene is designated tsn4. The resistant cultivars identified in this study are recommended for use in breeding programmes to improve tan spot resistance in common wheat. [source] Inheritance of insensitivity to culture filtrate of Pyrenophora tritici-repentis, race 2, in wheat (Triticum aestivum L.)PLANT BREEDING, Issue 3 2006P.K. Singh Abstract Tan spot of wheat is caused by the fungus Pyrenophora tritici-repentis. On susceptible hosts, P. tritici-repentis induces two phenotypically distinct symptoms, tan necrosis and chlorosis. This fungus produces several toxins that induce tan necrosis and chlorosis symptoms in susceptible cultivars. The objectives of this study were to determine the inheritance of insensitivity to necrosis-inducing culture filtrate of P. tritici-repentis, race 2, and to establish the relationship between the host reaction to culture filtrate and spore inoculation with respect to the necrosis component. The F1, F2, and BC1F1 plants and F2:8 lines of five crosses involving resistant wheat genotypes ,Erik', ,Red Chief', and line 86ISMN 2137 with susceptible cultivars ,Glenlea' and ,Kenyon' were studied. Plants were spore-inoculated at the two-leaf stage. Four days later, the newly emerged uninoculated third leaf was infiltrated with a culture filtrate of isolate Ptr 92,164 (race 2). Reactions to the spore inoculation and the culture filtrate were recorded 8 days after spore inoculation. The segregation observed in the F2 and BC1F1 generations and the F2:8 lines of all crosses indicated that a single recessive gene controlled insensitivity to necrosis caused by culture filtrate. This gene also controlled resistance to necrosis induced by spore inoculation. [source] Development of a cleaved amplified polymorphic sequence (CAPS) marker linked to pungency in pepperPLANT BREEDING, Issue 3 2005Y. Minamiyama Abstract The complete tack of pungency in pepper (Capsicum annuum L.) is controlled by a single recessive gene (c). To develop a molecular marker linked to the C locus, two segregating F2 populations (TM2 and TF2) derived from crosses between occasionally pungent and non-pungent peppers in C. annuum were used. Using the RAPD (random amplified polymorphic DNA) technique in combination with a bulked segregation analysis, two RAPD markers, OPD20-800 and OPY09-800, were obtained. Of the two markers, the more closely linked marker. OPY09-800, was converted into a codominant CAPS (cleaved amplified polymorphic sequence) marker using data from the alignment of the two allelic sequences. This CAPS marker was linked to the C locus (3.6 cM in the TF2 population), and polymorphism was detected among accessions within C. annuum. This marker might be helpful for the selection of a c gene in backcross and progeny tests in a conventional breeding system. [source] | ||||||||||