共查询到20条相似文献,搜索用时 15 毫秒
1.
2.
3.
Moving integrated weed management from low level to a truly integrated and highly specific weed management system using advanced technologies
下载免费PDF全文
![点击此处可从《Weed Research》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Integrated weed management (IWM) is one of the most commonly referred to approaches for sustainable and effective weed control in agriculture, yet it is not widely practiced, likely because current IWM systems fail to meet performance expectations of growers. The effectiveness and value of IWM systems should increase with increasing application specificity and true integration made possible with contemporary advances in technology, information systems and decision support. IWM systems can be classified based on their degree of application specificity and level of integration of tactics. In the application specificity pathway, a tactic is applied at a range of scales, from subfield to plant specific. In the integration pathway, multiple weed control tactics are combined in a synergistic manner. We hypothesise that the full value of IWM can and will be realised only when current and emerging technological innovations, information systems and decision tools are synergistically combined for use in real time. The True IWM system we envision requires automation and robotic technologies, coupled with information and decision support systems that are available or emerging but not yet enabled, in a proven integrated platform. Examples of low‐level, traditional and precision IWM systems are discussed, and research needs for a True IWM system are presented. We conclude that the immediate call should be for a long‐term investment in R&D and education (both theoretical and empirical) to develop and implement True IWM systems, an effort best accomplished in a public–private partnership where all essential entities are fully engaged and adequately resourced, including growers from all countries who will utilise IWM. 相似文献
4.
为明确高粱田主要杂草对HPPD抑制剂类除草剂喹草酮的抗性,采用整株生物测定法测定马唐Digitaria sanguinalis、稗Echinochloa crusgalli、狗尾草Setaria viridis、野稷Panicum miliaceum、反枝苋Amaranthus retroflexus和藜Chenbopodium alum六种主要杂草的敏感种群对喹草酮的敏感基线,同时测定全国不同生态区高粱田中这6种杂草对喹草酮的抗性水平。结果显示,喹草酮对野稷、稗、反枝苋和藜的防除效果较好,GR50介于12.76~32.72 g (a.i.)/hm2之间,GR90介于68.04~193.54 g (a.i.)/hm2之间,对马唐的防除效果略低,GR50介于44.23~56.19 g (a.i.)/hm2之间,GR90介于472.26~849.24g(a.i.)/hm2之间。采自全国不同生态区高粱田的马唐、稗、狗尾... 相似文献
5.
6.
7.
A research study of establishment techniques in plantations of Eucalyptus nitens (Deane et Maiden) Maiden and Eucalyptus regnans F Mueller was assessed for growth at age 12 years. Biomass of trees and woody weeds was determined in the 13th year to evaluate the long-term effect of herbicide treatment on plots established with optimum seedling tree and site preparation. Eucalyptus regnans produced only 60% of the biomass of E. nitens. Under-storey woody weed biomass under E. regnans comprised 18–30% of the total biomass compared with 6% for E. nitens plots. There was less total under-storey weed biomass under the herbicide-treated plots, but a similar weed leaf biomass. Under-storey weed leaf biomass contributed 14–40% of the total leaf biomass on the plots. Despite under-storey weed biomass being substantially greater on the no-herbicide plots sampled, this competition had not generally reduced growth of the trees compared with the herbicide-treated plots. Suitable site preparation, providing weed-free conditions at the time of planting, resulted in woody weed control adequate to establish seedlings and allow full growth without the use of herbicides, given suitable seedling material. Although pre-planting herbicide treatment was not necessary for optimum growth of E. nitens grown from bare-root transplants, it did improve growth of slower-growing planting stock. 相似文献
8.
9.
10.
Tobin L. Peever Michael G. Milgroom 《European journal of plant pathology / European Foundation for Plant Pathology》1995,101(1):93-99
Highly significant genetic variation (P<0.001) in resistance to the morpholine fungicides fenpropimorph, tridemorph and dodemorph and the piperidine fungicide, fenpropidin was found in different populations ofPyrenophore teres in North America and Europe which had not been previously exposed to these fungicides. Resistance phenotypes were continuously distributed for each fungicide in each population. Cross resistance relationships were determined by estimating genetic correlation coefficients in resistance to all pairwise combinations of fungicides. The majority of the correlation coefficients were highly positive for all fungicide combinations in all populations; eight of 36 (22%) coefficients were not significantly different from 1 (P>0.05). This result is consistent with the hypothesis that many of the same genes, or genes in gametic disequilibrium, control resistance to more than one fungicide in most populations ofP. teres and that these fungicides comprise a single cross resistance group. Three of 36 (8%) correlation coefficients were not significantly different from 0 (P>0.05) indicating that, in these populations, independent genes controlled resistance to these fungicides. The results of this study indicate that although most of the same genes control resistance to morpholine and piperidine fungicides inP. teres, differences in frequencies of these genes among populations can result in different cross resistance relationships from one population to another. 相似文献
11.
Comment: Number of sample populations required to determine the effects of herbicide resistance on plant growth and fitness 总被引:1,自引:0,他引:1
Experiments to determine the relative growth and fitness of herbicide–resistant and susceptible weeds commonly include only a single population of each. It is argued that such limited experimental designs can be misleading and should be avoided. Guidelines are given to aid decisions on choice of number of populations. 相似文献
12.
Several UK populations of the grass weed Alopecurus myosuroides were identified where high proportions of individuals showed resistance to the acetolactate synthase (ALS)‐inhibiting herbicides, mesosulfuron‐methyl + iodosulfuron‐methyl sodium mixture and sulfometuron‐methyl. Screening with sulfometuron, followed by DNA sequencing of the ALS gene from resistant and susceptible individuals, led to the identification of eight populations where a single point mutation segregated with resistance to sulfometuron. All highly resistant individuals from seven of eight populations showed a single‐nucleotide polymorphism (SNP) in the first position of the Pro197 codon of an A. myosuroides ALS gene, conferring a predicted proline to threonine target‐site change. One population showed resistant individuals with single‐nucleotide polymorphism in the second position of the Trp574 codon, conferring a predicted tryptophan to leucine substitution. No other mutations segregating with resistance were found. Enzyme assays confirmed that resistance was due to an altered form of ALS enzyme, which was less susceptible to inhibition by sulfonylureas, making this one of the first fully characterised cases of ALS target‐site resistance in a European grass weed. Increased information regarding the nature and distribution of ALS target‐site mutation may help support sustainable management strategies, allowing continued use of mesosulfuron + iodosulfuron against this weed in the UK. 相似文献
13.
蓟马是一类个体微小的昆虫,形态学特征观察困难,种内遗传多样性高,且部分害虫类蓟马寄主广泛,繁殖能力强,为害严重,已成为重要的农林类害虫。采用分子生物学手段对蓟马进行物种鉴定,可以解决传统形态学鉴定困难、局限性较大等问题,能提高物种鉴定的效率与准确性。目前,关于蓟马分子生物学鉴定的研究较多,其中,基于线粒体细胞色素氧化酶亚基( I cytochrome oxidase I,COI)基因片段的DNA条形码技术被广泛用于蓟马的快速准确鉴定、属内近缘种的区分及不同品系或生物型的鉴别。此外,开展蓟马类害虫种群遗传学的研究不仅有利于全面了解其遗传分化、适应性、入侵来源和扩散路径,还可为制订合理有效的监测预报和综合防治策略提供理论依据。目前,多种蓟马的种群遗传学研究表明地理隔离、寄主植物和微生物等因素影响其种内和种间的遗传多样性和遗传分化。本文综述了国内外有关蓟马的DNA条形码鉴定与种群遗传学研究进展,对目前蓟马物种鉴定中存在的问题进行讨论,并对未来的发展趋势进行展望。 相似文献
14.
Clark RD 《Pest management science》2012,68(4):513-518
BACKGROUND: For the last 15 years the agrochemical industry has focused on using genetic modification to put genes that confer resistance to existing commercial herbicides into crop plants rather than on discovering new herbicides with novel modes of action. The widespread appearance of weeds resistant to those herbicides is now causing the industry to revive their herbicide discovery programs. RESULTS: Elucidation of quantitative structure–activity relationships (QSARs) played a major role in the discovery and development of existing commercial herbicides, but the advent of genetically modified crops has caused published work (at least) in the area to drift from the industrial arena into academic studies. The focus has also turned inward, to refining models for established herbicide targets instead of elucidating new ones. CONCLUSION: This perspective highlights the importance of QSARs and quantitative structure–property relationships (QSPRs) to herbicide discovery in an historical context and provides some guidance as to how they might profitably be applied going forward. Copyright © 2011 Society of Chemical Industry 相似文献
15.
16.
Since weeds serve as hosts for nematode pests, the host status of 20 weed species (commonly occurring in fields of developing farmers) to Meloidogyne incognita and M. javanica, respectively, were investigated. Greenhouse studies showed that seven weed species had Rf values >1 for both nematode species indicating susceptibility, while 13 had Rf values ≤ 1 indicating resistance. Greenhouse results showed that Hibiscus trionum and Amaranthus tricolor were identified as the most susceptible and Chenopodium carinatum and Datura ferox the poorest hosts for M. incognita and M. javanica. For field experiments at Kuruman, Solanum retroflexum was the most susceptible weed to a M. javanica population, while the same was evident for H. trionum at Nelspruit, where a mixed population of M. incognita and M. javanica occurred and at Potchefstroom, where a population of M. incognita was present. Results from this study indicated that certain weed species are highly susceptible to root-knot nematodes and should be removed timely and effectively to prevent population level increases of root-knot nematode pests in the fields of farmers. 相似文献
17.
Diclofop-methyl resistance was evaluated in populations of Italian ryegrass ( Lolium multiflorum Lam.) infected and uninfected with fungal endophyte ( Neotyphodium ). Survival was tested in susceptible populations using herbicide screening. The results served as inputs to a model for investigating the role of endophyte infection in the evolution of L. multiflorum resistance to herbicide. The tolerance of infected plants varied depending on the origin of the population and the herbicide dose. Only in some populations and at some diclofop-methyl doses did plants infected with these endophytes have higher survivorship than endophyte-free plants. The model demonstrated that endophytes might indeed play an important role in the evolution of herbicide-resistant weeds, delaying the appearance of herbicide resistance. 相似文献
18.
The inheritance of partial resistance to race 2 of Albugo candida was studied in a canola-quality line of Brassica juncea . This partially resistant line was crossed with the susceptible B. juncea cultivar Commercial Brown. F1 , F1 (reciprocal), F2 , BC and doubled haploid generations from the cross were inoculated with a zoospore suspension of race 2 to study segregation of partial resistance. The partially resistant phenotype appeared to be controlled by a single dominant gene that has variable expression. This partial resistance can have implications in breeding for disease resistance against white rust, as adult plants did not develop hypertrophic growth or stagheads under greenhouse and field conditions. 相似文献
19.