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排序方式: 共有207条查询结果,搜索用时 31 毫秒
1.
Pheromones of nocturnal moths are derived from fatty acids produced as a result of the activity of acetyl-CoA carboxylase. This timely production is initiated in nocturnal moths by a tropic peptide, pheromone biosynthesis activating neuropeptide released into the hemolymph. In monocotyledonous plants, specific plastid acetyl-CoA carboxylase is inhibited by herbicides that target the eukaryotic form of the enzyme. We report evidence that these herbicides can also target pheromone biosynthesis by a moth, thereby implicating the acetyl-CoA carboxylase as a key regulatory enzyme in the pheromone biosynthetic pathway. These findings, whilst indicating the possible action of such herbicides on non-target organisms, also suggest a novel alternative method of insect pest management, which precludes sex-pheromone production and mating success, thereby reducing insect population growth. 相似文献
2.
《Journal of plant nutrition》2013,36(12):2453-2468
Abstract The top three leaves play important roles in biomass production and grain yield of rice (Oryza sativa L.) crop since the three leaves not only assimilate majority of carbon for grain filling during ripening phase, but also provide large proportion of remobilized‐nitrogen (N) for grain development during their senescence. The objectives of this study were to (a) compare senescence of the top three leaves and (b) compare the changes in N, chlorophyll, and ribulose‐1,5‐bisphosphate carboxylase/oxygenase (Rubisco) contents of the top three leaves after their full expansion in field‐grown rice plants. When the basis of comparison among the top three leaves was plant age in terms of days after transplanting (DAT), senescence generally started earliest in ?3rd leaf, intermediate in ?2nd leaf, and latest in flag leaf. If the basis of comparison among the top three leaves was leaf age in terms of days after full leaf expansion (DAFE), it was not clear which leaf senesced earlier. Senescence rate was generally greatest in flag leaf, intermediate in ?2nd leaf, and smallest in ?3rd leaf. Ribulose‐1,5‐bisphosphate carboxylase/oxygenase content declined earlier, and at a faster rate than N and chlorophyll contents during the senescence of all top three leaves. Correlation analysis indicated a close relationship between N and chlorophyll contents. Ribulose‐1,5‐bisphosphate carboxylase/oxygenase content correlated with N content better than with chlorophyll content. The suitability of N, chlorophyll, and Rubisco contents for quantifying the leaf senescence of field‐grown rice plants is discussed. 相似文献
3.
Status of black grass (Alopecurus myosuroides) resistance to acetyl-coenzyme A carboxylase inhibitors in France 总被引:1,自引:0,他引:1
C DÉLYE Y MENCHARI J-P GUILLEMIN† A MATÉJICEK S MICHEL C CAMILLERI‡ & B CHAUVEL 《Weed Research》2007,47(2):95-105
We assessed the contributions of target site‐ and non‐target site‐based resistance to herbicides inhibiting acetyl‐coenzyme A carboxylase (ACC) in Alopecurus myosuroides (black grass). A total of 243 A. myosuroides populations collected across France were analysed using herbicide sensitivity bioassay (24 300 seedlings analysed) and ACC genotyping (13 188 seedlings analysed). Seedlings resistant to at least one ACC‐inhibiting herbicide were detected in 99.2% of the populations. Mutant, resistant ACC allele(s) were detected in 56.8% of the populations. Among the five resistant ACC alleles known in A. myosuroides, alleles containing an isoleucine‐to‐leucine substitution at codon 1781 were predominant (59.5% of the plants containing resistant ACC alleles). Comparison of the results from herbicide sensitivity bioassays with genotyping indicated that more than 75% of the plants resistant to ACC‐inhibiting herbicides in France would be resistant via increased herbicide metabolism. Analysis of herbicide application records suggested that in 15.9% of the populations studied, metabolism‐based resistance to ACC‐inhibiting herbicides was mostly selected for by herbicides with other modes of action. Our study revealed the importance of non‐target site‐based resistance in A. myosuroides. Using herbicides with alternative modes of action to control populations resistant to ACC‐inhibiting herbicides, the recommended management approach, may thus be jeopardised by the widespread occurrence of metabolism‐based resistance mechanisms conferring broad‐spectrum cross‐resistance. 相似文献
4.
Diclofop-resistant Lolium species (ryegrass) is a major weed problem in wheat production worldwide. This study was conducted to determine the resistance pattern of diclofop-resistant ryegrass accessions from the southern United States to mesosulfuron-methyl, a recently commercialized herbicide for ryegrass control in wheat; to determine the cross-resistance pattern of a Lolium multiflorum Lam. (Italian ryegrass) accession, 03-1, to acetolactate synthase (ALS) and acetyl-CoA carboxylase (ACCase) inhibitors; and to determine the resistance mechanism of Italian ryegrass to mesosulfuron-methyl. Seventeen ryegrass accessions from Arkansas and Louisiana, including standard resistant and susceptible accessions, were used in this experiment. Fourteen of the 17 accessions were more resistant (four- to > 308-fold) to diclofop than the standard susceptible biotype. One accession, 03-1, was resistant to mesosulfuron-methyl as well as to other ALS inhibitor herbicides such as chlorsulfuron, imazamox and sulfometuron. Accession 03-1, however, did not show multiple resistance to the ACCase inhibitor herbicides diclofop, fluazifop, clethodim, sethoxydim and pinoxaden, nor to glyphosate. The in vivo ALS activity of the 03-1 biotype was less affected by mesosulfuron-methyl than the susceptible biotype. This indicates that the resistance mechanism of Italian ryegrass to mesosulfuron-methyl is partly due to an alteration in the target enzyme, ALS. It is concluded that diclofop-resistant ryegrass in the southern United States can be generally controlled by mesosulfuron-methyl. However, mesosulfuron-methyl must be used with caution because not all ryegrass populations are susceptible to it. There is a need for more thorough profiling of ryegrass resistance to herbicides. 相似文献
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早熟禾对精噁唑禾草灵、精喹禾灵、高效氟吡甲禾灵、炔草酸、精吡氟禾草灵、氰氟草酯、烯禾啶和苯草酮具有耐药性.而对烯草酮和吡喃草酮敏感。早熟禾生物型的乙酰辅酶A羧化酶(ACCase)对精嗯唑禾草灵的活性显著高于敏感杂草日本看麦娘.5个早熟禾生物型的,IC50值为敏感杂草日本看麦娘,IC50值的10.46~11.98倍:早熟禾ACCase氨基酸序列1781位点存在亮氨酸/异亮氨酸的多态性现象,而亮氨酸的存在是其它禾本科杂草对ACCase抑制剂除草剂产生抗性的主要原因之一:5个早熟禾生物型的ACCase基因表达量为日本看麦娘的4.67~7.37倍。早熟禾与日本看麦娘的ACCase活性、基因序列及基因表达量差异可能是导致早熟禾对精嗯唑禾草灵具有耐药性的靶标酶机理。 相似文献
8.
应用竞争PCR检测丙酸盐对体外培养牛肝细胞丙酮酸羧化酶mRNA水平的影响 总被引:3,自引:2,他引:1
根据牛肝细胞内PC(丙酮酸羧化酶)基因组与PCcDNA相比多含有一个内含子序列.在其中再插入一外源DNA序列.从而使最终构建的突变体片段的长度大于PCcDNA的长度,成功构建了PCcDNA的竞争DNA模板,然后应用竞争PCR方法研究了丙酸盐对体外培养新生牛单层肝细胞PCmRNA水平的影响。使单层肝细胞培养液中丙酸钠浓度分别为0、1.5、2.5、3.5、4.5、8.5、11.5mmol/L,处理24h,提取总RNA、逆转录,在同一体系中用相同引物扩增目的带和竞争模板带。结果表明.随着丙酸钠浓度的升高.PCmRNA水平呈上升趋势,提示肝细胞内PCmRNA的表达水平受培养液中丙酸钠浓度的影响。 相似文献
9.
稗草(Echinochloa crusgalli)根型ppc基因对水稻的遗传转化及其对光合速率的调节效应 总被引:1,自引:0,他引:1
稗草(Echinochloa crusgalli)是稻田中的C4光合型杂草,为了探索稗草ppc基因(Eppc)对水稻遗传转化的可行性及其对光合速率的调节效应,首次将含有稗草根型磷酸烯醇式丙酮酸羧化酶(phosphoenolpyruvate carboxylase,PEPC)基因ppc c DNA的2个植物表达载体p Ubi-Eppc、p Rbc S-Eppc通过农杆菌介导法对水稻进行了遗传转化。对分化植株进行的PCR、RT-PCR、克隆测序和Western杂交等结果均表明稗草ppc基因已经整合到了水稻基因组中,并且在转录和翻译水平都得到了表达。转基因水稻PEPC活性和气体交换参数测定结果表明T0代多数植株的PEPC活性高于对照,最高达到了对照的5.85倍;T0代大多数转基因植株叶片的净光合速率(Pn)比对照提高了20.00%,最大地提高了47.16%,同时叶片水分利用效率(WUE)也得到增强;T6代大部分转化植株的PEPC活性及Pn仍保持高于对照,本研究表明C3根型ppc基因过量表达也可以提高水稻的Pn,且证明稗草PEPC对光合作用具有较强的调节作用。 相似文献
10.
Nineteen tetraploid wheats (Triticum turgidum), differing in their agronomical behaviour and geographic origins were grown in two experiments and analysed for the following physiological traits: soluble leaf protein content, rubisco content, initial and potential carboxylase activities of this enzyme as well as its relative content in percentage of protein, the specific activity of the enzyme and its activation state. The results show a high genetic variability for all studied traits and more particularly for the initial carboxylase activity. High phenotypic correlation was observed between the rubisco content and its potential activities, in the first experiment. Correlation between souble leaf protein and rubisco content was significant in 9 genotypes of the second experiment. 相似文献