Effects of harvesting date and storage on the amounts of polyacetylenes in carrots, Daucus carota     

Kjellenberg L  Johansson E  Gustavsson KE  Olsson ME 《Journal of agricultural and food chemistry》2010,58(22):11703-11708

The amounts of three main polyacetylenes in carrots; falcarinol, falcarindiol, and falcarindiol-3-acetate, were determined by HPLC, during three seasons, in carrots harvested several times per season and at different locations in Sweden. The amounts of falcarindiol first decreased from a relatively high level and then increased later in the harvest season. The amounts of falcarindiol-3-acetate showed similar variations, whereas the amounts of falcarinol did not exhibit any significant variation during the harvest season. During storage the amount of polyacetylenes leveled off, increasing in samples initially low and decreasing in samples initially high in polyacetylenes. The amounts of all polyacetylenes varied significantly due to external factors and between stored and fresh samples. This variation opens up possibilities to achieve a chemical composition of polyacetylenes at harvest that minimizes the risk of bitter off-taste and maximizes the positive health effects reported in connection with polyacetylenes in carrots.  相似文献   

青贮微生物及其对青贮饲料发酵品质影响的研究进展   总被引：1，自引：0，他引：1  

许冬梅  张萍  柯文灿  郭旭生 《草地学报》2017,25(3)

青贮微生物在饲料发酵过程中起关键作用。无论是牧草表面附着的微生物还是外源添加的微生物菌剂在青贮发酵过程中对青贮微生物的群落结构及其演替过程都起着重要的作用,而青贮发酵过程中微生物的群落结构及其演替过程与代谢产物很大程度上影响着青贮饲料的发酵品质。本文阐述了青贮微生物群落结构,微生物在青贮过程中的演替及其对青贮饲料品质的影响。从目前研究结果来看,不同牧草及同种牧草生长在不同环境中其表面附着微生物存在很大差异。添加乳酸菌对提高青贮品质效果不稳定,还需了解牧草附着微生物特性决定是否需要接种乳酸菌以得到优质青贮饲料。  相似文献   

Mass Spawning by Green Algae on Coral Reefs     

KE Clifton 《Science (New York, N.Y.)》1997,275(5303):1116-1118

Predawn episodes of mass spawning by green algae (up to nine species in five genera on a single morning) intermittently cloud Caribbean waters. Species- and sex-specific bouts of anisogamous gamete release occurred synchronously and predictably on a given morning, with closely related species spawning at different times. Algal sexual reproduction was seasonal, but, unlike the mass-spawning behavior of other sessile marine organisms, showed no lunar or tidal cycling. The discovery of mass-spawning behavior by these algae has important implications for future studies of the reproductive ecology and speciation of a vital, yet poorly understood, component of the coral reef community.  相似文献   

混凝土早期体积变化与裂缝的成因   总被引：1，自引：0，他引：1  

柯昌君  钟金衡 《湖北农学院学报》2001,21(1):72-75

分析了混凝土早期体积的变化以及裂缝的形成与混凝土体积变化的关系。  相似文献   

海南省西甜瓜细菌性果斑病的发生与防治   总被引：1，自引：0，他引：1  

王爽  刘勇  罗丰  肖春雷  万三连  韩晓燕  柯用春  孔祥义 《中国蔬菜》2015,1(2):68-70

<正>近年来细菌性果斑病在海南西瓜、甜瓜生产上发生严重,其原因不仅与当地气候条件、栽培管理不当等有关,也与各地进行南繁的瓜类品种繁杂、种子消毒不彻底、病原远距离传播扩散有关。西瓜、甜瓜是海南省种植面积较为广泛、经济效益较高的农产品,2013年种植面积达1.97万hm2(29.55万亩)(农业部,2015)。细菌性果斑病是西瓜、甜瓜生产上的一种毁灭性病害,引起该病的病原菌为西瓜嗜酸菌(Acidovorax citrulli)(Schaad  相似文献   

棉花GbSTK基因调控开花和黄萎病抗性的功能研究     

CUI Jing  WANG Zhi-Cheng  ZHANG Xin-Yu  KE Hui-Feng  WU Li-Qiang  WANG Xing-Fen  ZHANG Gui-Yin  MA Zhi-Ying  ZHANG Yan 《作物学报》1962,47(1):30-41

Cotton is an important cash crop, and achieving disease resistance as well as early maturity is an important breeding goal. However, the molecular relationship between disease resistance and early maturity of cotton is still a research gap. In previous study, we identified a GbSTK gene response to V. dahliae that could enhance Verticillium wilt resistance in transgenic Arabidopsis. In this study, we found that GbSTK was more highly expressed in resistance and/or tolerant varieties than in susceptible varieties. Knocking down of GbSTK expression in Nongda 601 showed that the silenced plants displayed serious disease symptoms, with disease index from 27.5 (tolerant) to 63.2 (susceptible), suggesting that GbSTK positively regulates cotton Verticillium wilt resistance. More interesting, we found that GbSTK could promote the development of Arabidopsis. At the flowering time point, the average number of rosette leaves in transgenic lines was 7.5, significantly less than the mock plants, and the transgenic plants bloomed five to seven days earlier than the control. The FT and SOC1 gene, regarded as marker genes in Arabidopsis flowering signaling pathway, maintained higher expression level in transgenic lines than in the mock, indicating that GbSTK could accelerate flowering via regulating FT and SOC1 gene expression. We also obtained 30 candidate proteins that could interacted with GbSTK via yeast double hybrid test, which helped to further revealing the molecular regulatory network of GbSTK. Taken together, we first identified a functional gene that could improve disease resistance and early flowering, which would provide a reference for genetic improvement of cotton disease resistant and early maturity.  相似文献   

云南3种野生稻中抗白叶枯病基因的鉴定   总被引：1，自引：0，他引：1  

李定琴  陈玲  李维蛟  柯学  余腾琼  李娥贤  黄兴奇  程在全 《作物学报》2015,41(3):386-393

白叶枯病是水稻生产上最重要的细菌性病害之一,培育抗病新品种是防治白叶枯病最经济有效的途径。然而,栽培稻来源的抗病基因数量有限,并且部分抗病基因的抗病谱窄。因此,从野生稻中发掘抗病基因,将有利于培育抗病谱广且抗病能力强的水稻新品种。本研究通过抗性鉴定和PCR分析,检测云南野生稻中的抗白叶枯病基因。结果表明,云南野生稻对2个代表性白叶枯病菌Y8和PXO99具有不同程度的抗性,疣粒野生稻甚至达到免疫的程度。功能标记检测结果显示,3种野生稻中均不含xa5、xa13和Xa21抗病基因,元江普通野生稻含Xa23和Xa3/Xa26基因或其同源基因,景洪普通野生稻中含Xa1、Xa3/Xa26和Xa27基因或同源基因,药用野生稻含Xa3/Xa26基因或同源基因,而疣粒野生稻含有Xa27抗性基因。本研究结果为进一步发掘和克隆云南野生稻中的抗白叶枯病新基因提供了理论参考。  相似文献   

Genetic study of bolting and stem length in sugar beet (Beta vulgaris L.) using a factorial cross design     

S. Y. Sadeghian  E. Johansson 《Euphytica》1992,65(3):177-185

Summary The objective was to study the genetic basis of bolting and stem length in sugar beet full-sibs, developed by a factorial mating design (N.C. design II). The extent to which the inheritance of these characters can be attributed to the additive and non-dominance variation was investigated. The genetic analysis consisted of three sets (4×10, 4×8, and 3×8) of progenies. Estimates of additive genetic variance (² _A) and variance due to dominance deviations with some fractions of epistatic variance (² _D) were obtained for both characters. Bolting had a relatively large proportion of total genetic variance accounted for by ² _A. In most cases, non-additive effects were also important in determining the type of gene action in bolting. Stem length showed similar genetic variation to bolting susceptibility. Bolting resistance seemed to be dominant to the bolting susceptibility in most cases. Narrow sense heritability estimated for bolting was generally very large (0.93 to 0.96), which suggests that early generation selection for bolting resistance in a sugar beet population would be successful.  相似文献   

Effect of two wheat genotypes and Swedish environment on falling number, amylase activities, and protein concentration and composition     

Eva Johansson 《Euphytica》2002,126(1):143-149

Variation in falling number, amylase activities, protein concentration and composition were investigated in two wheat cultivars grown in Sweden over two seasons, in four locations, with four N fertilizer rates, with and without fungicide treatment. The results showed that;

•	Tarso had higher falling number, amylase activities, protein concentration and amount of most protein components compared to Kosack.
•	The environment (year, location, N rate and fungicide treatment) influenced falling number, alpha amylase activities, and protein concentration and composition.
•	Two processes were related to low falling numbers; late maturity leading to poor starch and protein quality and excessive rains leading to break-down of starch and proteins.
•	Poor starch and protein properties influenced the bread-making quality to a higher extent than break-down of starch and proteins.

This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

甘蓝型油菜柱头特异启动子的克隆和序列分析   总被引：1，自引：0，他引：1  

柯丽萍  郑滔  吴学龙  陈锦清  祝水金 《农业生物技术学报》2007,15(2):257-262

芸薹属自交不亲和相关基因SLR1只在柱头中特异表达，根据已知的SLR1基因启动子序列设计特异引物，用PCR法从几个甘蓝型油菜品种和品系中分离得到相应的启动子片断，进行序列比较分析后，并构建它们与GFP融合的植物表达载体，转化拟南芥，验证所分离到的启动子的时空特异性。研究表明，来自自交不亲和羽衣甘蓝和来自自交亲和的甘蓝型油菜的SLR1启动子具有相似的序列结构和相同的组织特异表达功能。该结果将为下一步研究S-locus基因在甘蓝型油菜中的表达和相互作用奠定基础。  相似文献