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91.
92.
T. Hodgkin 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1981,59(2):79-82
Summary The total vegetative node number, rate of node production and number of sprouts over 13 mm diameter were recorded for 10 F1 Brussels sprout cultivars and 45 progenies derived by intercrossing and selfing them. Significant differences, resulting from additive gene action, were found between the 10 cultivars and between their progenies for both characters. For total node number there was also evidence of dominant gene action. Total node number and rate of node production were closely correlated as were total node number and the number of harvested sprouts. The factors causing differences in rate of node production are indicated and the relationship of this character to other Brussels sprout yield components is outlined. 相似文献
93.
The efficacy of oxamyl in controlling Heterodera schachtii on cabbage was determined by applying various contbinations of soil drenches at 6.7 kg (a.i.)/ha and foliar sprays at 0.04 kg (a.i.)/100 liters of water to cabbage seedlings. Pretransplant drenches provided some control of H. schachtii over a 13-week period. A single foliar spray of oxamyl 1 week before transplanting apparently prevented penetration of H. schachtii larvae; post-transplant sprays were relatively ineffective. A pretransplant or transplant drench combined with a foliar application 2 weeks after transplanting provided the most effective control. The effectiveness of drenches plus post-transplant sprays is probably due to the spray augmenting the action of the drench in inhibiting the development of larvae after penelration. 相似文献
94.
Occurrence of two serologically distinct groups within Bacillus thuringiensis serotype 3 ab var. kurstaki 总被引:7,自引:0,他引:7
Two groups distinguishable on the basis of crystal serology have been identified within Bacillus thuringiensis var kurstaki (serotype 3 ab). The toxicities of these two groups to Trichoplusia ni and Heliothis virescens expressed as ratio also differed. It is suggested that serotype 3 ab be separated into two subgroups designated as K-1 and K-73. 相似文献
95.
Take-all on turfgrass caused by Gaeumannomyces graminis var. avenae (Gga) occurs as patches of yellowish plants. On some patches the central zone was recolonized by the same grass species, Festuca sp., previously damaged by the fungus despite the centrifugal extension of the disease. This disease remission was assimilated to decline. Rhizosphere bacterial counts showed that total population of bacteria was nearly the same in all zones across the patches. However, the ratio of fluorescent Pseudomonas spp./ total bacteria was 1/22, 1/15.4, 1/3.5 and 1/2.9 in the disease free area, the front margin of the patch, in the damaged part of the patch, and in the recolonized central part respectively. Furthermore, in this last mentioned zone, 44 to 82% of the fluorescent Pseudomonas spp. were antagonistic in vitro to Gga, whereas only 12 to 34% from the disease free area were antagonistic. So the development of take-all on turf induced quantitative and qualitative changes in populations of fluorescent pseudomonads. The remission of the disease in the center was correlated to higher amount of antagonistic fluorescent pseudomonads in this part of the patches. This typical patch with the well defined zones can provide a good model for the study of changes in bacterial populations related to the build up of take-all decline. 相似文献
96.
《Bioscience, biotechnology, and biochemistry》2013,77(11):1890-1891
The effects of the ovarian hormones progesterone and estrone on the conversion of tryptophan to nicotinamide in rats were investigated. Female rats were fed for 35 days with a 20% casein diet, or with a 20% casein diet containing 0.1% progesterone, or 0.001% estrone, or 0.1% progestrone and 0.001% estrone. The conversion ratio of tryptophan to nicotinamide on the last day of the experiment was 2% in the groups fed with the 20% casein diet and the diet containing 0.1% progesterone, but around 1.2% in the group fed with 0.001% estrone, and 0.7% in the group fed with 0.1% progesterone and 0.001% estrone. These results demonstrated that administration of ovarian hormones significantly decreased the conversion of tryptophan to nicotinamide. 相似文献
97.
The short- to medium-term viability and growth of Metarhizium anisopliae var. acridum conidia were investigated when combined with six insecticides, at three different concentrations. All of the insecticides used in this study were suitable for immediate spraying with M. anisopliae var. acridum conidia except for fenitrothion. Fipronil, teflubenzuron, and fenitrothion formulations significantly reduced conidial viability over time. The 10% teflubenzuron treatment caused loss of viability relatively quickly with 9.9% germination after 28 days. Mycelial growth was affected by all the treatments except fenitrothion. 相似文献
98.
Ginseng and the seed of Zizyphus jujuba var. spinosa, which are traditional Chinese medicinal materials, were often used in ancient Chinese recipes as a pair of medicines. They can replenish the primordial qi and tonify the spleen. This study investigated the effects of ginseng and the seed of Zizyphus jujuba var. spinosa (GS) extract on gut microbiota diversity in rats with spleen deficiency syndrome (SDS). A total of 52 compounds (including 16 flavonoids, 35 saponins, and 1 alkaloid) were identified and analyzed from the GS extract by UPLC‐Q‐Orbitrap‐MS/MS. The GS extract significantly increased the relative abundance of Firmicutes and Bacteroidetes in rats with SDS but decreased that of Proteobacteria and Actinobacteria. At the genus level, the GS extract significantly increased the relative abundance of Lactobacillus and Bifidobacterium in rats with SDS but decreased that of Streptococcus, Escherichia‐Shigella, Veillonella, and Enterococcus. In addition, the GS extract influenced glucose and amino acid metabolism. In summary, the results showed that the GS extract changed the structure and diversity of gut microbiota in rats with SDS and balanced the metabolic process. 相似文献
99.
100.
马蔺(Iris lactea var. chinensis)是鸢尾属多年生草本盐生植物,具有很高的耐盐性和观赏价值。为研究马蔺耐盐的分子机制,通过cDNA末端快速扩增技术(RACE)从马蔺中克隆到一个WRKY转录因子基因IlWRKY28,获得了1 302 bp的全长cDNA序列,其包含一个108 bp 5′末端非翻译区(UTR),一个174 bp 3′末端UTR和一个1 020 bp开放阅读框。IlWRKY28编码339个氨基酸,预测的蛋白质分子量为37.22 kD,等电点为7.04。氨基酸序列分析显示,IlWRKY28包含一个保守的WRKY基序和一个C2H2型锌指结构域。系统发育分析表明,马蔺IlWRKY28与菠萝(Ananas comosus)AcWRKY28和藏北嵩草(Kobresia littledalei)ClWRKY28亲缘关系最近。荧光定量PCR分析显示,盐处理后,IlWRKY28基因在马蔺地上部显著上调表达。该研究结果为进一步研究IlWRKY28在马蔺适应高盐胁迫中的功能和作用机制奠定了重要的分子基础。 相似文献