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1.
A study was conducted to determine the spray deposition patterns for air blast sprayers used to apply chemicals to the canopy of Semillon grapevine in vineyard. The application carried out in 12 bars and three sprayer speed (2.1-4.9-7.7 km h(-1)). The spray deposition was measured on the point in the different distances (1.5-3-6-9 m). Tartrazine were applied as tracer material. Maximum spray deposit was obtained 66.1 mg cm(-2) at sprayer speed of 2.1 km h(-1) and minimum deposit was obtained 37.1 mg cm(-2) at sprayer speed of 7.7 km h(-1). The results showed that the sprayer speeds had significant effect on spray deposit distribution and increasing of the sprayer speed increased drift.  相似文献   

2.
《Crop Protection》1986,5(1):3-7
Paddy rice is usually sprayed with different types of conventional hydraulic nozzles and application rates. Spray droplets are more easily captured by the tip of rice leaves; this phenomenon was therefore studied with rice plants in a settling tower so that deposition of droplets occurred under controlled conditions. Further tests were carried out in rice fields by dirferent methods. The deposition rate was generally higher at the leaf tip compared with other parts, whether the leaf was vertical, pointing downwards at an angle of 60 degrees, horizontal or in a normal position. Similar results could be obtained if leaf-like water-sensitive paper strips were used instead of a natural rice leaf. The deposition and distribution pattern found on field rice leaves confirmed these results. Deposits on water-sensitive papers of different widths (2–25 mm) showed fewer droplets as the target width increased.  相似文献   

3.
The use of tunnel sprayers should be encouraged because they can potentially reduce pesticide input and drift in orchards. They could also allow smaller plot size in multifactorial trials in which fully randomized or randomized block designs are recommended. However, the effectiveness of plant protection products applied with tunnel sprayers cannot be reliably assessed without a thorough investigation into spray distribution in tree canopies. A set of three experiments was undertaken in an apple orchard to compare a new type of recycling tunnel sprayer with a standard axial fan sprayer, both of them fitted with either conventional hydraulic hollow cone nozzles (ATR) or drift-mitigating air induction cone nozzles (TVI). Its performance was assessed in terms of 1) spray deposit and coverage in the canopy, 2) sedimentation drift (spray drift to the ground) and 3) collection and recycling rate of the liquid sprayed in the tunnel. Artificial targets composed of cellulose papers and water-sensitive papers were used to evaluate the spray deposit and coverage at similar target positions for each treatment. A fluorescent dye was used as the spray tracer.  相似文献   

4.
Summary In 1994, a postal questionnaire was sent to 41 institutes in 27 countries to obtain information on the national potato cultivar testing programmes in Europe. Responses were received from 19 countries. Foliage, tuber and yield characteristics were assessed in all countries but the number of sites and replicated varied considerably between the countries. Cooking and taste qualities were measured in most countries using relatively simple methods but processing characteristics were tested less commonly. Susceptibility to the most common diseases, i.e. late blight, common scab, leafroll and PVYo, was assessed in over 75% of the countries while resistance to another 21 disease and 4 potato cyst nematode pathotypes was assessed by various countries, depending on their national importance. Many of the assessments were based on records of natural infection although controlled inoculation tests were done more frequently for the more important diseases.  相似文献   

5.
Consistent spray coverage that is evenly distributed throughout the canopy is necessary to control pest populations that can negatively affect yield. As applicators are switching to Coarser spray quality nozzles to reduce risk and liability of pesticide spray drift, concerns about efficacy loss are growing. Previous research has indicated that small droplets are the most effective at penetrating through crop canopies, but newer nozzle technologies have improved the effectiveness of larger droplet or Coarser sprays. Research was conducted to assess the canopy penetration of nozzles that produce Coarse, Very-Coarse and Extremely-Coarse spray qualities compared to nozzles that produce Fine and Medium spray qualities. Kromekote collectors were positioned in four configurations in an oat (Avena sativa L.) var. ‘Yarran’ (AusWest Seeds, Forbes, NSW, Australia) crop to quantify the coverage and droplet number densities (droplets cm−2) across three application carrier volume rates: 50, 75 and 100 L ha−1. Applications were made in the field in 30 cm tall, tillering oats, with collectors arranged in a randomised complete block design with three replications. The entire study was repeated on the following day. Results showed that droplet number densities were inversely related to the droplet size produced by the nozzles, yet coverage was increased more by application volume rate than droplet size. Thus, both spray drift reduction and improved canopy penetration can be achieved with proper nozzle selection and operation parameters for the control of agronomic pests.  相似文献   

6.
我国是大豆消费大国和净进口国,大豆和大豆油自给率严重不足,进口来源相对集中。如何降低大豆对外依存度,提高大豆油供给,是当前新时期保障我国食物安全的重要课题。文章依据中国大豆供需现状,在油脂加工视角下对我国大豆作比较优势分析,阐述了大豆油自给率不足的根本原因,并提出开发和推广耐盐碱地种植高产大豆、提升高油大豆的种植面积和出油率、科学合理大豆油消费、其他油料作物替代消费等建议来提升我国大豆油自给率水平。  相似文献   

7.
Summary Dormancy, incubation periods and physiological vigour or rusticity of new potato cultivars were determined during the official cultivar assessment programme in Switzerland. A total of 60 cultivars were assessed, including the standards, Sirtema (early), Bintje (mid-early) and Eba (mid-late); Russet Burbank was re-examined. Large variation between cultivars was observed, from 2000 to 3400 day-degrees for dormancy and from 1900 to 3700 day-degrees for incubation periods, expressed as sums of cumulated temperatures above zero centigrade. Field trials with physiologically aged seed identified the physiological vigour or rusticity of the cultivars. Those with low vigour or low rusticity showed poor emergence and yield after prolonged sprouting periods. The lowest produced less than 10% of the yield of seed of optimum physiological age stored under standard conditions. However, some high vigour or very rustic cultivars produced 100% of their potential yield. There was no relationship between earliness and physiological vigour. Vigour is very useful to farmers because it indicates those cultivars that are sensitive to warm storage or long sprouting periods and desprouting before planting. Dr Winiger passed away on 9th October 2000  相似文献   

8.

Background  

The free-living nematode Caenorhabditis elegans is the predominant model organism in biological research, being used by a huge number of laboratories worldwide. Many researchers have evaluated life-history traits of C. elegans in investigations covering quite different aspects such as ecotoxicology, inbreeding depression and heterosis, dietary restriction/supplement, mutations, and ageing. Such traits include juvenile growth rates, age at sexual maturity, adult body size, age-specific fecundity/mortality, total reproduction, mean and maximum lifespan, and intrinsic population growth rates. However, we found that in life-cycle experiments care is needed regarding protocol design. Here, we test a recently developed method that overcomes some problems associated with traditional cultivation techniques. In this fast and yet precise approach, single individuals are maintained within hanging drops of semi-fluid culture medium, allowing the simultaneous investigation of various life-history traits at any desired degree of accuracy. Here, the life cycles of wild-type C. elegans strains N2 (Bristol, UK) and MY6 (Münster, Germany) were compared at 20°C with 5 × 109 Escherichia coli ml-1 as food source.  相似文献   

9.
Previous research has shown the effectiveness of an ULV (Ultra-Low Volume) sprayer compared to a conventional sprayer for weed control in row crop applications. This sprayer produced comparable disease control and foliar nutrient applications to a conventional sprayer in turfgrass, but has not previously been evaluated for weed control in established turf. Four weed control field studies were conducted in the spring and summer of 2012 and 2013 at the University of Nebraska-Lincoln: John Seaton Anderson Turfgrass Research Facility near Mead, NE, USA to compare the weed control efficacy between a novel ULV sprayer and a conventional sprayer. The studies compared the two sprayers for the control of: ground ivy and dandelion in established turf in a summer application; preemergence control of large crabgrass in established turf in a late spring application and ground ivy control in established turf in a late spring application. No differences were observed in weed control between sprayer types in the four studies over both years of the study despite a thirty fold decrease in application volume rate across different herbicide modes-of-action in all of the studies. The Kamterter ULV sprayer system may be a useful and effective management option for control of the weeds in turfgrass.  相似文献   

10.
The pattern and quantity of pesticide deposition may affect the efficacy of pesticide treatments. In this study we evaluated under laboratory conditions the efficacy of two petroleum-derived spray oils (PDSO) (Laincoil®, an nC21 oil with a content of 83% w/v, Oil A, and Sunspray Ultrafine®, an nC21 with a content of 85% w/v, Oil B, both with an unsulfonated residue of 92%) applied at 1.5% concentration at five volumes (0.5, 1, 2, 3 and 4 ml) against different stages of Aonidiella aurantii Maskell (Homoptera: Diaspididae). In parallel, we characterized the deposition pattern of treatments resulting from these five volumes and two PDSOs. The objective was to model deposition characteristics and efficacy as a function of the deposited volume in order to determine the optimum volume per unit surface that should be applied to control this pest. Different models that depend on the developmental stage and relate to the efficacy of the treatment as a function of the deposited volume have been obtained for both PDSOs, thus providing a scientific basis for product efficacy comparison. Furthermore, our results are also relevant to find an adequate trade-off between sprayed pesticide volume and expected efficacy.  相似文献   

11.
In a mature Vitis labrusca L. “Niagara” vineyard, we compared an airblast sprayer and an air-assisted rotary atomizer (AARA) low-volume sprayer for coverage of grape clusters and control of grape berry moth, Paralobesia viteana. In addition, the effect of spray volume on control of fungal diseases was evaluated using the fungicides ziram and azoxystrobin applied with an airblast sprayer. For evaluation of coverage, sprayers applied kaolin clay at 28 kg/ha to grapevines while operating at low, medium and high water volumes. Kaolin residues on grape clusters were analyzed to compare the total amount of spray material deposited, percent of fruit surface covered, number of deposits, size of deposits and distance between deposits. There were no significant differences between sprayers or water volumes in the total amount of kaolin deposited on clusters, but the percent surface coverage was much greater on outside-facing berry surfaces (facing the sprayer) than inside-facing surfaces (facing the rachis). On the outside-facing berry surfaces, the airblast sprayer at 468 L/ha of water (medium volume) provided the highest percent coverage, the greatest density of deposits, the largest deposit diameter, and the smallest distance between deposits. On the inside-facing berry surfaces, the same sprayer–volume combination provided the highest percent coverage and greatest deposit diameter, but deposits from the airblast sprayer operating at 935 L/ha (high volume) had the smallest distance between deposits. No significant differences between sprayers or among water volumes were detected in the deposit density on the inside-facing berry surfaces. Bioassays of grape clusters sprayed with fenpropathrin or methoxyfenozide using the airblast or AARA sprayers at two water volumes revealed the greatest fruit protection from P. viteana at the higher volume for the airblast sprayer, but at the lower volume for the AARA sprayer. Spray volume of the airblast sprayer also affected disease control by the protectant fungicide ziram more than by the systemic fungicide azoxystrobin, with 468 L/ha providing better control than 187 L/ha. However, for most diseases, fungicide type was more influential than spray volume in determining the disease control outcome. The results of this study emphasize the need for appropriate water volumes relative to the sprayer and pesticide being used to optimize pest and disease control in juice grape vineyards.  相似文献   

12.
Creation of new plant type and breeding super rice in northern China   总被引:2,自引:0,他引:2  
ThesubjectofbreedingsuperjaponicariceinnorthernChina,wasgrownoutoftheresearchthroughcrossingin dicawithjaponicaandbreedingforidealplanttypes.Sofar,ithasworkedwiththreestages:researchonfunda mentalprinciples,creationofgermplasmsfornewplanttypes(NPT),an…  相似文献   

13.
《Field Crops Research》2002,75(1):37-45
The rice (Oryza sativa L.) “new plant type” (NPT), currently under development at the International Rice Research Institute, Philippines, differs in genetic background and plant architecture from the semidwarf Indica varieties that now predominate in tropical lowland areas. The NPT is derived from tropical Japonica germplasm and has fewer and larger stems and panicles than do semidwarf Indica varieties. We compared stem borer damage and resistance in NPT lines and semidwarf Indica varieties under field and greenhouse conditions. Stem borer damage in field plots of the NPT lines IR65564 and IR68011 was higher than in plots of the Indica varieties IR64 and IR72 during the 1999 dry season but not the wet season. In both seasons, IR68011 had higher densities of egg masses of the striped stem borer (SSB, Chilo suppressalis) than did the other three entries. There were no consistent differences among entries in density of egg masses of the yellow stem borer (YSB, Scirpophaga incertulas). In the 2000 wet season, stem borer populations were low, but SSB egg masses were found only on IR68552-100, the only NPT line in the experiment. In all three seasons, NPT lines had higher proportions of SSB larvae and pupae in stems after harvest, and lower proportions of YSB, than did Indica varieties. In artificially infested field cages, SSB larval survival was highest on reproductive stage plants of IR68011 in the 1999 dry season and there was a trend of higher YSB adult weight on IR68011 in the 1999 dry and wet seasons. Three NPT lines and three Indica varieties evaluated under greenhouse conditions showed no consistent differences in resistance to either stem borer species, as measured by percent survival from egg to adult and female development time and weight. The lack of consistent differences in stem borer survival and development between the NPT lines and Indica varieties was contrary to the expectation that the morphology of the NPT would render it more susceptible to stem borers. Our results indicate that NPT lines are not consistently or strongly more susceptible to stem borers than are improved Indica varieties and suggest that ovipositional attractiveness to SSB is a factor contributing to higher stem borer damage to some NPT lines.  相似文献   

14.
Sorghum is an important worldwide crop whose yield can be significantly reduced by anthracnose (Colletotrichum sublineola) and grain mold diseases (multiple fungi). The identification of new genetic sources of resistance to both diseases is imperative for the development of new sorghum varieties. To this end, a total of 80 exotic germplasm accessions from Burkina Faso (BFA) and South Africa (ZAF) were evaluated for anthracnose and grain mold resistance during two planting periods in 2012 at the USDA-ARS experimental farms in Isabela, Puerto Rico. Twelve accessions were resistant to anthracnose during both evaluations of which 10 are originally from BFA. The anthracnose resistant accessions identified herein had a hypersensitive reaction characterized by lesions having red and purple color. Likewise, 9 accessions exhibited grain mold resistance after being inoculated with a mixture of a conidial suspension of Fusarium thapsinum, Fusarium semitectum, and Curvularia lunata during both periods. Eight of these accessions (PI 586182, PI 586186, PI 647705, PI 647706, PI 647707, PI 647708, PI 647710, and PI 647712) originated from BFA, while one (PI 61666) is from ZAF. The PI 586186 was the only accession that exhibited resistance to both anthracnose and grain mold. The grain mold resistant accession PI 61666 has a panicle shape that resembles a standard United States commercial type sorghum and is also photoperiod insensitive. The results presented herein indicate that the BFA germplasm could be an important source for anthracnose and grain mold resistance genes. The integration of these anthracnose and grain mold resistant germplasm into sorghum breeding programs should aid in expanding the genetic diversity and in the development of new resistant varieties.  相似文献   

15.
采用小区对比试验方法,研究了播量、移栽基本苗对水稻新品种盐粳218生育及产量的影响。结果表明,降低播量可使盐粳218秧苗的干物重、充实度、带蘖率增加。处理A1B4的单产为604.4 kg/667 m2,比A3B6、A1B2、A2B3、A3B4、A1B3、A2B5、A2B4、A3B5处理分别增产了7.8%、7.0%、4.7%、3.2%、2.6%、2.2%、1.3%、1.3%,其单位面积有效穗数及颖花数、生物产量及齐穗后干物质积累量占籽粒产量百分比均较高。在播量100、200、300 g/m2前提下,对应移栽基本苗4.5万~5.5万/667 m2、5.5万~6.5万/667 m2、6.0万~7.0万/667 m2均可使盐粳218获得较高的产量与效益。  相似文献   

16.
广东国外水稻种质资源的引进和评价利用   总被引:3,自引:0,他引:3  
国外水稻种质资源在对我国水稻矮化育种、三系杂交稻恢复系的选育和优质抗病品种选育等方面起到很大作用。广东省农科院水稻研究所中期种质资源库现有保存的国外水稻种质资源4 671份。通过引进国外水稻种质资源利用于分子生物学和遗传育种研究中,选育出一系列优质、抗病的水稻新品种,如通过外引材料IR9965-48-2选育出外选35,再利用外选35育成梅三五2号、矮三芦占、七袋占等优质水稻品种,并推广应用。通过引进各种类型的国外水稻种质资源用于研究,对我国水稻育种研究的可持续发展起到促进作用。  相似文献   

17.
广东国外水稻种质资源的引进和评价利用   总被引:1,自引:0,他引:1  
国外水稻种质资源在对我国水稻矮化育种、三系杂交稻恢复系的选育和优质抗病品种选育等方面起到很大作用。广东省农科院水稻研究所中期种质资源库现有保存的国外水稻种质资源4 671份。通过引进国外水稻种质资源利用于分子生物学和遗传育种研究中,选育出一系列优质、抗病的水稻新品种,如通过外引材料IR9965-48-2选育出外选35,再利用外选35育成梅三五2号、矮三芦占、七袋占等优质水稻品种,并推广应用。通过引进各种类型的国外水稻种质资源用于研究,对我国水稻育种研究的可持续发展起到促进作用。  相似文献   

18.
Breeding has enabled the development of wheat genotypes with different quality characteristics and end uses. Despite its numerous positive properties that make it one of the most cultivated crops, wheat is known to induce allergic reactions in predisposed consumers. Genetic modification (GM) technology for crop improvement has recently emerged and its impact on allergenicity must be evaluated, as recommended by the Codex Alimentarius.  相似文献   

19.
Forage maize grown in areas where spring temperatures are low and accumulated heat is limited will be restricted in terms of maturity and thus nutritional value. A stagnant growth phase is commonly caused by low temperatures between germination and the five-leaf stage, which could be caused by reduced mineral availability. The effects on maize plant development and harvest characteristics of supplying phosphorus and zinc to young plants in a foliar spray were investigated. Three different application dates, between the four-leaf and the seven-leaf stage, were compared. Applying the phosphorus and zinc foliar spray at the four-leaf stage resulted in a significant ( P  < 0·05) increase in starch content at harvest. Cob index [proportion of plant dry matter (DM) in the cob] was increased ( P  < 0·05) by applying the nutrient spray at the four-, five- and seven-leaf stages. However, there was no effect on DM yield, suggesting some alteration in partitioning within the plant.  相似文献   

20.
Neorogioltriol is a tricyclic brominated diterpenoid isolated from the organic extract of the red algae Laurencia glandulifera. In the present study, the anti-inflammatory effects of neorogioltriol were evaluated both in vivo using carrageenan-induced paw edema and in vitro on lipopolysaccharide (LPS)-treated Raw264.7 macrophages. The in vivo study demonstrated that the administration of 1 mg/kg of neorogioltriol resulted in the significant reduction of carregeenan-induced rat edema. In vitro, our results show that neorogioltriol treatment decreased the luciferase activity in LPS-stimulated Raw264.7 cells, stably transfected with the NF-κB-dependent luciferase reporter. This effect on NF-κB activation is not mediated through MAPK pathways. The inhibition of NF-κB activity correlates with decreased levels of LPS-induced tumor necrosis factor-alpha (TNFα) present in neorogioltriol treated supernatant cell culture. Further analyses indicated that this product also significantly inhibited the release of nitric oxide and the expression of cyclooxygenase-2 (COX-2) in LPS-stimulated Raw264.7 cells. These latter effects could only be observed for neorogioltriol concentrations below 62.5 μM. To our knowledge, this is the first report describing a molecule derived from Laurencia glandulifera with anti-inflammatory activity both in vivo and in vitro. The effect demonstrated in vitro may be explained by the inhibition of the LPS-induced NF-κB activation and TNFα production. NO release and COX-2 expression may reinforce this effect.  相似文献   

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