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排序方式: 共有1240条查询结果,搜索用时 15 毫秒
1.
Marek Jindra 《Journal of Pesticide Science》2021,46(1):3
Insect Growth Regulators (IGRs) represent advanced, bio-rational insecticides. This Special Issue reflects progress in IGR development that has been enabled by insight into the molecular principles of biosynthetic or hormone signaling pathways. The unifying principle is aiming at processes and molecular targets that are unique to arthropods and ideally to narrower insect taxa representing pests or disease vectors. While some strategies of obtaining the desired compounds for chemical intervention rely on rational, structure-based design or computational power, others exploit technologies allowing automated, high-throughput screening of large chemical libraries. All avenues leading to selective and environmentally safe pest control are valid as we face the imminent threat of the declining world insect population. 相似文献
2.
The Inheritance of Aliphatic Glucosinolates in Brassica napus 总被引:2,自引:0,他引:2
The inheritance of aliphatic glucosinolates was studied in crosses between synthetic B. napus lines and oilseed rape cultivars. Six unlinked loci are described which determine the aliphatic glucosinolate profile of B. napus. One locus regulates the presence or absence of propyl glucosinolates, while another regulates the expression of pentyl glucosinolates. Two loci regulate the removal of the terminal H3CS-group from the amino acid derivative to produce alkenyl glucosinolates as opposed to methylthioalkyl and methylsulphinylalkyl glucosinolates, regardless of the length of the alkyl chain. Likewise, another two loci regulate the hydroxylation of both butenyl and pentenyl glucosinolates. The functional alleles at one of the hydroxylation loci results in significantly more hydroxylation than those at the other locus. The large number of aliphatic glucosinolates which have been described in Brassica thus results from an interaction between genes which regulate side chain elongation and genes which modify the structure of the side chain, regardless of its length. The implications of this study for the biosynthesis of aliphatic glucosinolates, the origin of B. napus and the potential to manipulate the leaf and seed glucosinolate profile of oilseed rape are discussed. 相似文献
3.
The effects of root-applied chalcone at 0.15 mmol L−1 on the growth and lignin biosynthesis in maize were investigated. The contents of 4-coumarate: CoA ligase (4CL, EC 6.2.1.12) substrates in maize shoots were increased more rapidly in the samples with chalcone application than in the control and the increase occurred at ≤ 3 h after the application (HAA). The lignin content was reduced by chalcone at ≤ 6 HAA. The shoot growth was suppressed by chalcone at ≤ 9 HAA. Consequently, the results suggest that chalcone suppressed maize growth by inhibiting monolignol biosynthesis. 相似文献
4.
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
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7.
Navid Adnani Emmanuel Vazquez-Rivera Srikar N. Adibhatla Gregory A. Ellis Doug R. Braun Tim S. Bugni 《Marine drugs》2015,13(10):6082-6098
With respect to bacterial natural products, a significant outcome of the genomic era was that the biosynthetic potential in many microorganisms surpassed the number of compounds isolated under standard laboratory growth conditions, particularly among certain members in the phylum Actinobacteria. Our group, as well as others, investigated interspecies interactions, via co-culture, as a technique to coax bacteria to produce novel natural products. While co-culture provides new opportunities, challenges exist and questions surrounding these methods remain unanswered. In marine bacteria, for example, how prevalent are interspecies interactions and how commonly do interactions result in novel natural products? In an attempt to begin to answer basic questions surrounding co-culture of marine microorganisms, we have tested both antibiotic activity-based and LC/MS-based methods to evaluate Micromonosporaceae secondary metabolite production in co-culture. Overall, our investigation of 65 Micromonosporaceae led to the identification of 12 Micromonosporaceae across three genera that produced unique metabolites in co-culture. Our results suggest that interspecies interactions were prevalent between marine Micromonosporaceae and marine mycolic acid-containing bacteria. Furthermore, our approach highlights a sensitive and rapid method for investigating interspecies interactions in search of novel antibiotics, secondary metabolites, and genes. 相似文献
8.
OsHemA gene,encoding glutamyl-tRNA reductase(GluTR) is essential for chlorophyll biosynthesis in rice(Oryza sativa)
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ZENG Zhao-qiong LIN Tian-zi ZHAO Jie-yu ZHENG Tian-hui XU Le-feng WANG Yi-hua LIU Ling-long JIANG Ling CHEN Sai-hua WAN Jian-min 《农业科学学报》2020,19(3):612-623
Chlorophyll(Chl) biosynthesis is essential for photosynthesis and plant growth. Glutamyl-tRNA reductase(GluTR) catalyzes glutamyl-tRNA into glutamate-1-semialdehyde(GSA) and initiates the chlorophyll biosynthesis. Even though the main role of GluTR has been established, the effects caused by natural variations in its corresponding gene remain largely unknown. Here, we characterized a spontaneous mutant in paddy field with Chl biosynthesis deficiency, designated as cbd1. With intact thylakoid lamellar structure, the cbd1 plant showed light green leaves and reduced Chl and carotenoids(Cars) content significantly compared to the wild type. By map-based gene cloning, the mutation was restricted within a 57-kb region on chromosome 10, in which an mPingA miniature inverted-repeat transposable element(MITE) inserted in the promoter region of OsHemA gene. Both leaf color and the pigment contents in cbd1 were recovered in a complementation test, confirming OsHemA was responsible for the mutant phenotype. OsHemA was uniquely predicted to encode GluTR and its expression level was dramatically repressed in cbd1. Transient transformation in protoplasts demonstrated that GluTR localized in chloroplasts and a signal peptide exists in its N-terminus. A majority of Chl biosynthesis genes, except for POR and CHLG, were down-regulated synchronously by the repression of OsHemA, suggesting that an attenuation occurred in the Chl biosynthesis pathway. Interestingly, we found major agronomic traits involved in rice yield were statistically unaffected, except for the number of full grains per panicle was increased in cbd1. Collectively, OsHemA plays an essential role in Chl biosynthesis in rice and its weak allele can adjust leaf color and Chls content without compromise to rice yield. 相似文献
9.
A. Rodionov S. Nii‐Annang T. Fischer A. Gattinger O. Bens T. Raab R. F. Hüttl 《Soil Use and Management》2014,30(1):78-87
Application of hydrophilic polymers composed of cross‐linked polyacrylate can improve soil water‐holding capacity and accelerate the restoration of post‐mining substrates. In this work, we studied the persistence of a polyacrylate polymer incorporated into a soil and its impact on plant nutrients at a reclamation site of former lignite mining in Lusatia (Germany). In contrast to autumn application, the incorporation of the polymer enhanced the sequestration of plant‐derived carbon in the soil, which was reflected by a significant increase in the concentration of a lignin marker. Attenuated total reflexion–Fourier transform infrared spectra (ATR‐FTIR) and total elemental contents in the applied polymer suggested an intensive cation exchange between the polymer framework and the soil‐forming substrate. In addition, there was an enrichment of carbonaceous material, which seems to reduce the swelling and thus the water‐holding capacity of the cross‐linked polyacrylate. Conversely, this process protected the polymer structure from rapid decomposition. 相似文献
10.
《Soil Science and Plant Nutrition》2013,59(1):26-31
Abstract The present study was undertaken to identify the effects of manganese (Mn) on the activity of peroxidase (PO) and the amount of ascorbic acid (AsA) and lignin, as well as the cell viability of suspension-cultured tea cells (Camellia sinensis L. cv. Yabukita). Cells were grown in B5 medium (containing 0.06 mmol L?1 Mn) and cultured for 24 h in medium with a Mn concentration of 0.9 mmol L?1 as an excess treatment. No significant difference was observed between cellular growth and the viability of the cultured tea cells after treatment with excess Mn compared with cells grown under control conditions, although the content of Mn in cells in the excess Mn treatment was 12-fold higher than that of the control cells. The amount of total AsA was also not affected by the Mn treatment. The activity of ionically wall-bound peroxidase (IPO) increased in the presence of excess Mn, unlike the content of lignin. Conversely, the activities of soluble PO and covalently wall-bound PO decreased with excess Mn. These findings suggested that IPO might contribute to Mn tolerance in tea cells. However, its role in the mechanism(s) of Mn tolerance has not been elucidated. 相似文献