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The mode of inheritance of fifteen induced morphological mutants in diploid wheat Triticum monococcum L. was determined. The results showed that earliness, reduced height, uniculm, liguleless branched spike, compact ear, and free-threshing habit of each of these mutants is the result of a single recessive mutation. Red awns and xantha traits are controlled by two recessive genes with duplicate and inhibitory gene interactions, respectively. Some of the early and dwarf mutants were non-allelic. One dwarf GA3-insensitive mutant with recessive gene action may be a new source. Mutants such as early maturing, dwarf and free threshing habit may be of significance in breeding diploid wheat. 相似文献
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分别于1994年3月和1995年3月从同一棉田,采集分离了48个大丽轮枝菌菌株.应用RAPD技术,从240个随机引物中筛选了17个扩增效果好的引物,对供试菌株进行了DNA指纹分析.结果表明:17个引物对48个菌株扩增出120条DNA分子片段,其中43条分子片段为多态带,占35.83%.将扩增结果输入计算机,用PHYLIP分析软件(3.5版本),UPGAME程序进行类聚分析,结果表明95年的5个菌株与其它菌株存在明显的遗传差异. 相似文献
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Koul O Daniewski WM Multani JS Gumulka M Singh G 《Journal of agricultural and food chemistry》2003,51(25):7271-7275
The biological activity of the limonoids prieurianin and epoxyprieurianin isolated from Entandrophragma candolei (Harms) (Meliaceae) and their respective acetates was assessed using the gram pod borer, Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae). The compounds exhibited strong antifeedant activity in a diet choice bioassay with epoxyprieurianin acetate being most effective with 48.3 ppm deterring feeding by 50% (DI50) and prieurianin the least effective (DI50 = 91.4 ppm). The effect on growth of larvae was concomitant with the reduced feeding by neonate and third instar larvae. In nutritional assays, all the compounds reduced growth and consumption when fed to larvae without any effect on efficiency of conversion of ingested food (ECI), suggesting antifeedant activity alone. No toxicity was observed nor was there any significant affect on nutritional indices following topical application, further suggesting that prieurianin-type limonoids act specifically as feeding deterrents. 相似文献
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Twelve synthesized ainphiplonds involving Karnal bunt (Neovossia indica)-resisiant accessions of Triticum monococum, T. boeoticum and Aegilops sqiwrrosa and susceptible but otherwise well adapted and high yielding T. Durum cultiviars were evaluated for Karnal bunt resisiance under artificial inoculation conditions. All ihe synthetic amphiploids, except DWI. 5031 x T. monocoirtum aniphlploid, were free from Karnal bunt disease indicating that the Karnal bunt resistance or T. motsococcum, T. boeoticMrn and Ae, squarrosa is expressec in the presence of the dnrum complement. The importance and utilization of the amphiploids fox breeding wheat varieties resistant to karnal bunt are discussed. 相似文献
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Inheritance of Isoproturon Tolerance in Durum Wheat Transferred from Triticum monococcum 总被引：1，自引：0，他引：1
The inheritance of isoproturon tolerance exhibited by the selected progenies of durum wheat was investigated. This tolerance to the herbicide isoproturon had been transferred from Triticum monococcum to durum wheat cultivars. It was shown to be conditioned by a single dominant gene 相似文献
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Multani DS Briggs SP Chamberlin MA Blakeslee JJ Murphy AS Johal GS 《Science (New York, N.Y.)》2003,302(5642):81-84
Agriculturally advantageous reduction in plant height is usually achieved by blocking the action or production of gibberellins. Here, we describe a different dwarfing mechanism found in maize brachytic2 (br2) mutants characterized by compact lower stalk internodes. The height reduction in these plants results from the loss of a P-glycoprotein that modulates polar auxin transport in the maize stalk. The sorghum ortholog of br2 is dwarf3 (dw3), an unstable mutant of long-standing commercial interest and concern. A direct duplication within the dw3 gene is responsible for its mutant nature and also for its instability, because it facilitates unequal crossing-over at the locus. 相似文献
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Koul O Multani JS Singh G Daniewski WM Berlozecki S 《Journal of agricultural and food chemistry》2003,51(10):2937-2942
The biological activity of 6beta-hydroxygedunin isolated from Azadirachta indica A. Juss. was assessed using the gram pod borer, Helicoverpa armigera (Hubner), and Asian armyworm, Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae), alone and in combination with other limonoids, gedunin, salannin, nimbinene, and azadirachtin. The compound exhibited growth inhibitory activity in artificial diet bioassays, with 24.2 and 21.5 ppm, respectively, inhibiting growth by 50%. This efficacy was higher in comparison to gedunin (EC(50) = 50.8 and 40.4 ppm), salannin (EC(50) = 74.5 and 72.0 ppm), and nimbinene (EC(50) = 391.4 and 404.5 ppm). Azadirachtin, however, remained the most active neem allelochemical against both insect species. Nutritional assays clearly demonstrated that, though relative consumption and growth rates of fourth instar larvae were reduced, gedunin-type compounds induced physiological toxicity, evident by reduced efficiency of conversion of ingested food (ECI) in feeding experiments. Salannin and nimbinene, on the contrary, induced concentration-dependent feeding deterrence only. In feeding experiments, combinations of the compounds revealed that when azadirachtin was present in a mixture, EC(50) values did not deviate from the individual efficacy of azadirachtin (0.26 and 0.21 ppm, respectively) against H. armigera and S. litura larvae. However, a combination without azadirachtin did show a potentiation effect with potent EC(50) values among structurally different molecules, i.e., when salannin or nimbinene was combined with 6beta-hydroxygedunin or gedunin rather than structurally similar salannin + nimbinene or 6beta-hydroxygedunin + gedunin. Obviously, azadirachtin being the most active compound in neem is not synergized or influenced by any other limonoid, but other non-azadirachtin limonoids were more potent in specific combinations vis-à-vis the structural chemistry of the compound. It is obvious from the present study that potentiation among non-azadirachtin limonoids having explicitly two different modes of action, such as feeding deterrence and physiological toxicity, may be playing a significant role in the potentiation effect. 相似文献
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在温室人工接种鉴定了澳大利亚16个棉花种植地区30个棉花黄萎病菌株的致病性.结果表明:根据人工接种5个棉花品种的抗感反应和病情指数,30个供试菌株划分为4种致病类型.致病类型I(3个菌株)具有较强的致病能力,致病类型Ⅳ(5个菌株)的致病能力较弱.致病类型Ⅱ(12个菌株)和致病类型Ⅲ(10个菌株)的致病能力中等,为澳大利亚棉花种植地区的主要菌系类型. 相似文献
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The occurrence of homozygous matromorphic progenis in Pisum sativum L. has, been assessed by using heterozygous female parents in intervarietal and intergeneric crosses. The pollen was subjected to three treatments, i.e. prickle pollination (delayed), gamma irradiation and giibberellic acid (GA3) application, The genetic status of the induced matromorphic progeny was determined by using, multiple gene markers. The frequency or occurrence of homomatromorphs was 3 to 7 per cent, which needs to be increased by pod, ovule or embryo culture, respectively. 相似文献
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