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1.
Non-lethal alternatives are needed to manage the damage caused by wild birds to oilseed sunflower crops (Helianthus annuus Linnaeus). We evaluated field residues and experimental applications of an anthraquinone-based repellent (active ingredient 50% 9,10-anthraquinone) to minimize red-winged blackbird (Agelaius phoeniceus Linnaeus) depredation of oilseed sunflower. Chemical residues from experimental applications of the anthraquinone-based repellent (4.7 l/ha and 9.4 l/ha; low, high) in a ripening oilseed sunflower field were 481 ppm and 978 ppm anthraquinone at the beginning of blackbird damage, and 385 ppm and 952 ppm anthraquinone at the end of blackbird damage, respectively. Prior to harvest, we observed 402 ppm and 462 ppm anthraquinone in the oil, and 27 ppm and 165 ppm anthraquinone in the pomace from crushed sunflower achenes previously sprayed with the low and high applications, respectively. For the purpose of developing application strategies useful for avian repellents, we subsequently investigated blackbird feeding response to oilseed sunflower treated with the anthraquinone-based repellent and either a registered insecticide or a registered fungicide popularly used for ripening sunflower. We observed a positive concentration–response relationship among blackbirds exposed to anthraquinone and the insecticide (a.i. 8.4% esfenvalerate), or anthraquinone and the fungicide (a.i. 23.6% pyraclostrobin). Blackbirds reliably discriminated between untreated sunflower and that treated with 1810 ppm anthraquinone and 0.1% of the insecticide or 1700 ppm anthraquinone and 0.14% of the fungicide during our preference experiments. Given that ripening achenes are inverted from conventional pesticide applications throughout much of the period associated with blackbird depredation, we also evaluated blackbird repellency of the anthraquinone-based repellent applied to involucral bracts (i.e., the back of sunflower heads) of oilseed sunflower. Blackbirds did not discriminate between untreated involucral bracts and those treated with foliar applications comparable to 4.7 l/ha or 9.4 l/ha; blackbirds consumed more achenes from untreated sunflower heads than from those treated with 18.7 l/ha of the anthraquinone-based repellent. Supplemental repellent efficacy studies should investigate blackbird response to anthraquinone-based repellents (e.g., ≥4.7 l/ha) within 10–100 ha sunflower fields and include independent field replicates with predicted bird damage, repellent application strategies developed for protection of ripening crops, pre- and at-harvest repellent residues, and bird damage and crop yield measurements. 相似文献
2.
The present experiments were designed to identify inexpensive substitutes for
-pulegone, an effective vertebrate repellent. In experiment 1, European starlings (Sturnus vulgaris) were presented with
-pulegone and 12 additional menthone derivatives in one-cup tests. No derivative was as effective as
-pulegone. In experiment 2, starlings were presented with
-pulegone,
-pulegone and
-pulegone in onecup tests.
-pulegone was as aversive as
-pulegone, and both
-pulegone and
-pulegone were more aversive than
-pulegone. More extensive evaluation of
-pulegone as a vertebrate repellent appears warranted. 相似文献
3.
研究30%烟嘧磺隆·莠去津·硝磺草酮可分散油悬浮剂在甜玉米田的应用效果,在甜玉米不同叶龄期开展田间试验,评价其对杂草的防除效果及对甜玉米的安全性。结果表明,30%烟嘧磺隆·莠去津·硝磺草酮可分散油悬浮剂在甜玉米3～4叶期或6～7叶期施药,900～1 575 g a.i./hm2剂量范围内对甜玉米品种粤甜28安全,对玉米田常见杂草凹头苋、光头稗、马唐和香附子的防效及增产效果均显著高于对照药剂38%莠去津悬浮剂2 160 g a.i./hm2播后苗前处理。推荐30%烟嘧磺隆·莠去津·硝磺草酮可分散油悬浮剂在900～1 350 g a.i./hm2范围内,甜玉米3～5叶期茎叶喷雾使用。 相似文献
4.
In the United States, fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), is a target species of transgenic corn (Zea mays L.) expressing pyramided Bacillus thuringiensis proteins. In 2011, a total of 150 F2 two-parent families of S. frugiperda were established using single-pair matings of feral individuals collected from three locations in Louisiana and Florida. The objective of this study was to determine the susceptibility of these field derived families of S. frugiperda to a pyramided Bt corn hybrid containing Agrisure®Viptera™ 3111 traits. For each F2 family, 96 neonates were assayed on leaf tissue of Agrisure®Viptera™ 3111 corn in the laboratory. None of the 150 families survived for 7 days on leaf tissue of the Bt corn plants. The results demonstrate that the field populations of S. frugiperda collected from Louisiana and Florida were susceptible to the pyramided Bt corn product containing Agrisure®Viptera™ 3111 traits. The data generated in this study can be used as baseline data for resistance monitoring. 相似文献
5.
通过理化方法对5种不同类型的14个鲜食玉米品种在不同灌浆期子粒的营养成分进行分析,研究不同类型鲜食玉米子粒主要营养成分的积累动态,筛选能够指示不同类型鲜食玉米最佳采收期的客观理化指标。结果表明,鲜食玉米灌浆期子粒的可溶性总糖、蔗糖、还原糖、蛋白质、支链淀粉、直链淀粉和含水量在不同品种间、不同灌浆期间差异极显著。随着子粒的发育,不同类型鲜食玉米品种的可溶性总糖和蔗糖含量呈动态曲线变化,变化趋势都是先上升后下降;还原糖含量和含水量呈不断下降的趋势;直链淀粉和支链淀粉含量呈不断上升的趋势;蛋白质含量变化幅度很小,变化趋势不明显。根据鲜食玉米营养成分与品质的关系,提出子粒含水量结合可溶性糖含量和粗淀粉含量可分别作为甜玉米和糯玉米最佳采收期的指标。 相似文献
6.
Control of western cherry fruit fly (Rhagoletis indifferens Curran) using thiamethoxam in sucrose bait (sucrose only) and spinosad bait (GF-120, spinosad in a mix of sugar, protein, ammonium acetate, and other ingredients) in cherry orchards with external fly pressure and the residual activity of these baits were studied in Washington state and Utah, U.S.A., in 2010 and 2011. Thiamethoxam baits applied weekly controlled larval infestations better than spinosad bait applied weekly in one of four trials and did not differ from spinosad bait applied weekly in the remaining trials. Thiamethoxam baits applied every two weeks controlled larval infestations better than spinosad bait applied every two weeks in two of three trials, and did not differ statistically from spinosad bait applied weekly. Thiamethoxam bait that was aged on sweet cherry leaves in the field for 0, 7, 14, and 21 days killed flies more rapidly than spinosad bait that was aged for the same periods and reduced oviposition more than spinosad bait in the laboratory. Thiamethoxam bait retained activity up to 21 days of aging whereas spinosad bait lost activity after 14 or 21 days of aging. Results suggest that when there is external fly pressure, the potentiality of thiamethoxam bait to kill mature R. indifferens more rapidly than spinosad bait may not always translate to better fly control. However, when sprays are applied every two weeks, the longer residual activity of thiamethoxam than spinosad bait does appear to translate to better fly control. This study presents thiamethoxam with sucrose as a new option for an effective bait spray against R. indifferens. 相似文献
7.
Knowledge of the crop-weed competition period is vital for designing effective weed management strategies in crop production systems. Field studies were conducted at the Agricultural Research Institute, Kahramanmaras, Turkey in 2013 and 2014 to determine the critical period for weed control (CPWC) in three corn (Zea mays L.) types (field corn, popcorn, and sweet corn). A four parameter log-logistic model described the relationship between relative crop yield to both increasing duration of weed interference and length of weed-free periods. The relative yield of corn was influenced by duration of weed-infested or weed-free period, regardless of corn types. Increasing periods of weed interference significantly reduced corn yields in both years. In field corn, the CPWC ranged from 175 to 788 growing degree days (GDD) in 2013 which corresponded to V2–V12 growth stages, and 165–655 GDD (V1–V10 growth stages) in 2014 based on the 5% acceptable yield loss (AYL) level. In popcorn, the CPWC ranged from 92 to 615 GDD (VE–V10 growth stages) in 2013 and 110–678 GDD (V1–V10 growth stages) in 2014. In sweet corn, the CPWC ranged from 203 to 611 GDD in 2013 (V2–V10 growth stages) and 182–632 GDD (V2–V10 growth stages) in 2014. The practical implication of this study is that weed management should be initiated around V1 stage and maintained weed-free up to V12 stage in all corn types to prevent yield losses greater than 5%. These findings could help corn producers improve the cost effectiveness and efficacy of their weed management programs. 相似文献
8.
利用简化基因组测序技术SLAF-seq,对国内外引进选育的81份鲜食甜、糯玉米自交系进行遗传多样性分析。结果表明,共获得803 058个SLAF标签,其中,多态性SLAF标签373 764个。通过序列分析,获得169 128个有效单核苷酸(SNP)多态标记,利用这些SNP标记分析和构建了81份鲜食甜、糯玉米资源的群体结构和系统发生树,并将其分为2个群。结果表明,简化基因组测序技术SLAF-seq能高效、低廉地开发出大量SNP标记,是作物种质资源群体遗传分析的有效工具。研究结果为甜玉米不同基因的聚合、温-热种质杂交育种、鲜食甜、糯玉米亚种间杂交育种提供依据,有利于鲜食甜、糯玉米自交系的高效利用、品种选育及杂种优势群的建立。 相似文献
9.
设施菜地夏季休闲期甜玉米经济产量及环境效益分析 总被引：2，自引：0，他引：2
在北京市门头沟、房山、大兴和通州等4个区选择15个典型设施菜地,设置田间观察对比试验,研究在北方设施菜地夏季甜玉米作为填闲作物的实际经济、环境综合效益。试验结果表明,种植甜玉米有较好经济效益,经济产量达15 168.0～20 332.8kg/hm2。在环境效益方面,种植甜玉米后可有效减少浅层土壤中的硝态氮含量,降低淋溶风险。与常规休闲(休闲期不种植作物)相比,种植甜玉米可使设施菜地0～100cm土层中的硝态氮含量平均减少290.4kg/hm2。在夏季休闲期种植甜玉米是北方设施菜地兼顾经济和环境效益的有效种植措施之一。 相似文献
10.
特用玉米种子沙引发处理对其萌发及幼苗生理特性的影响 总被引：1，自引：0，他引：1
以糯玉米、爆裂玉米和甜玉米3种特用玉米为材料,测定沙引发处理后种子萌发指标、幼苗形态和生理指标的变化。结果表明,沙引发能显著提高糯玉米和甜玉米的种子活力,对3种特用玉米的幼苗生长具有显著的促进作用,但对种子发芽率无显著影响。沙引发处理显著提高了3种类型特用玉米幼苗的过氧化物酶(POD)和超氧化物歧化酶(SOD)活性,显著降低了丙二醛(MDA)含量。沙引发效果受基因型影响,对种子萌发的促进作用表现为糯玉米>甜玉米>爆裂玉米;对幼苗生长的促进作用表现为甜玉米>爆裂玉米>糯玉米。沙引发能够提高幼苗体内抗氧化酶的活性,从而增强幼苗对外界环境的适应能力。 相似文献
11.
Captive starlings (Sturnus vulgaris) and house sparrows (Passer domesticus) were given choices between untreated turkey crumbs, and similar food treated with one of five chemical repellents (quinine sulphate, methiocarb, dinol sulphite, TS-69 and tannic acid), with or without the addition of a blue dye. All birds avoided the treated food to about the same extent, although starlings showed greater aversion to tannic acid when it was coloured. Sparrows developed aversions to tannic acid and TS-69 more quickly if the food was coloured than if it were not. Birds of both species avoided the blue-colured food even when it was not paired with a repellent; this prevented measurements of the persistence of colour aversions once the repellents were omitted. The implications of these results are discussed in relation to the use of added colour cues to enhance the effects of chemical repellents to protect crops from bird pests. 相似文献
12.
Verticillium dahliae is the causal agent of strawberry wilt. A microencapsulated terpene product containing cineole, camphor and borneol, digestate from anaerobic digestion, and BioFence™ derived from a mustard-based defatted seedmeal were tested for their suppressive activity against V. dahliae. First, naturally infested soil was amended with microencapsulated terpene, lavender waste pellet and BioFence™ (pellet) in a laboratory test to assess the efficacy against V. dahliae. Next, mini-field-plot experiments were conducted to evaluate the efficacy of individual and combined use of terpene, BioFence™ (liquid) and digestate against V. dahliae; sterile distilled water treatment and untreated control were also included. In the laboratory test, all treatments significantly reduced V. dahliae densities, with the control efficacy ranging from 27% (BioFence™) to 69% (lavender waste pellet). Although the lowest (1×) rate of terpene treatment resulted in a much lower control efficacy (35%) than the other two higher rates (3× – 55%; 9× – 53%), these differences were not statistically significant. In the field mini-plot trials, all treatments led to significant reductions in the V. dahliae density, with the efficacy ranging from 50% (digestate) to 78% (combined three-product treatment), irrespective of the initial wilt level. There were no significant differences in all comparisons of pairwise treatments except between digestate and combined three-product treatment. For the combined two or three-product treatments, the observed efficacy was significantly less than the expected efficacy on the assumption of Bliss independence. Furthermore, there were no significant differences between the observed efficacy of combined treatments and the best single component product efficacy. Although the observed efficacy for the combined three-product treatment was consistently higher than the best single component across replicate plots, such a difference was not statistically significant. The results indicate the value of these alternative treatments in practice but these are not likely to reduce V. dahliae inoculum sufficiently to eliminate the risk of strawberry wilt and question the value of combined treatments. 相似文献
13.
Stacy D. Rodriguez Lisa L. Drake David P. Price John I. Hammond Immo A. Hansen 《Journal of insect science (Online)》2015,15(1)
Reducing the number of host-vector interactions is an effective way to reduce the spread of vector-borne diseases. Repellents are widely used to protect humans from a variety of protozoans, viruses, and nematodes. DEET (N,N-Diethyl-meta-toluamide), a safe and effective repellent, was developed during World War II. Fear of possible side effects of DEET has created a large market for “natural” DEET-free repellents with a variety of active ingredients. We present a comparative study on the efficacy of eight commercially available products, two fragrances, and a vitamin B patch. The products were tested using a human hand as attractant in a Y-tube olfactometer setup with Aedes aegypti (Linnaeus) and Aedes albopictus (Skuse), both major human disease vectors. We found that Ae. albopictus were generally less attracted to the test subject’s hand compared with Ae, aegypti. Repellents with DEET as active ingredient had a prominent repellency effect over longer times and on both species. Repellents containing p-menthane-3,8-diol produced comparable results but for shorter time periods. Some of the DEET-free products containing citronella or geraniol did not have any significant repellency effect. Interestingly, the perfume we tested had a modest repellency effect early after application, and the vitamin B patch had no effect on either species. This study shows that the different active ingredients in commercially available mosquito repellent products are not equivalent in terms of duration and strength of repellency. Our results suggest that products containing DEET or p-menthane-3,8-diol have long-lasting repellent effects and therefore provide good protection from mosquito-borne diseases. 相似文献
14.
15.
R. W. Summers 《Crop Protection》1985,4(4):520-528
A study was carried out on the behaviour of starlings (mainly juveniles) which are pests in cherry orchards where they eat ripening fruit. Observations on 17 radio-tagged starlings during the cherry-picking season showed that most individuals continued to feed in the orchards on consecutive days despite the use of a variety of scarers. Distress calls of starlings played through loudspeakers were effective in that they temporarily scared starlings, but birds returned during the periods when no distress call was played. However, starlings no longer responded to these distress calls after the period between days 7 and 13. Captive starlings could not maintain their weight on a diet of cherries and the maximum daily intake was 25 cherries, amounting to 1·5 times the bird's own weight. The length of time spent in the orchards by radio-tagged birds (on average 2·8 hours) was far longer than the time needed to eat 25 cherries. It is concluded that the present arrangement of scarers was inefficient and that the netting-in of an orchard would be more effective. 相似文献
16.
Performance consistency of reduced atrazine use in sweet corn 总被引：1，自引：0，他引：1
Martin M. Williams II Rick A. BoydstonR. Ed Peachey Darren Robinson 《Field Crops Research》2011,121(1):96-104
Atrazine is the most widely used herbicide in North American corn production; however, additional restrictions on its use in the near future are conceivable. Currently, a majority of commercial sweet corn fields suffer losses due to weeds, despite widespread use of atrazine. Field experiments were conducted in the primary North American production areas of sweet corn grown for processing to determine the implications of further reductions in atrazine use on weed control and crop yield. A range of atrazine doses (0-1120 g ha−1) applied postemergence with tembotrione (31 g ha−1) were tested in two hybrids differing in canopy architecture and competitive ability with weeds. Atrazine applied postemergence reduced risk (i.e. more variable outcomes) of poor herbicide performance. Atrazine doses up to 1120 g ha−1 with tembotrione improved grass control and broadleaf weed control in five of eight and seven of eight environments, respectively. Of the three environments which had particularly low broadleaf weed control (<50%) with tembotrione alone, sweet corn yield was improved with atrazine. Hybrid ‘Code128’ produced a taller, denser canopy which was more efficient at capturing light and competing with weeds than ‘Quickie’. As a result, greater crop competitiveness decreased risk of incomplete weed control as atrazine dose was reduced. Atrazine's contribution to weed control and yield protection was greatest when other aspects of weed management resulted in poor weed control. Should atrazine use be further restricted or banned altogether, this research demonstrates the importance of improving other aspects of weed management systems such as herbicidal and non-chemical tactics. 相似文献
17.
基于SSR标记构建甜玉米群体的核心种质 总被引：1，自引：0，他引：1
利用40对SSR引物分别分析56份超甜玉米和88份普甜玉米群体材料,基于非加权算术平均配对法(UPGMA)聚类分析和位点优先取样法,分别筛选出14个超甜玉米核心材料和19个普甜玉米材料作为两个亚群体种质。t测验表明,两个亚核心种质与原始群体的等位变异无显著差异(P0.05),等位变异保留率分别为87.81%和89.13%,有效地保留了原始材料群体的遗传变异。两个亚群核心种质与原始材料群体13个表型性状的均值、标准差、极差、变异系数和Shannon-Weaver多样性指数(H’)的平均符合率都在80%以上,并且均值差异百分率(MD)和方差差异百分率(VD)均小于20%,极差符合率(CR)和变异系数变化率(VR)均大于80%,符合核心种质的质量评价标准。构建的甜玉米核心种质最大程度地保留了原始群体的遗传多样性和表型变异,能够有效地代表原始甜玉米材料群体。 相似文献
18.
Protein contamination on refuge kernels due to cross-pollination from Bt corn to non-Bt corn ears is a major concern in the use of a seed mixture refuge strategy (“RIB”) for resistance management of ear-feeding pests. In this study, occurrence, distribution, and ear damage of the corn earworm, Helicoverpa zea (Boddie), were evaluated in three planting patterns of non-Bt and Bt corn plants containing Genuity® SmartStax™ traits. The three planting patterns were 1) pure stands of 27 Bt plants; 2) pure stands of 27 non-Bt plants; and 3) one non-Bt plant in the center surrounded by 26 Bt plants. A total of six trials were conducted in open field conditions with natural infestations in 2011 and 2012. Egg populations of H. zea were distributed randomly or uniformly, and the number of eggs laid was similar between Bt and non-Bt corn ears regardless of the planting patterns, suggesting that females of H. zea have no egg-laying preference between Bt and non-Bt plants. Bt corn plants containing Genuity® SmartStax™ traits were equally effective in the control of H. zea in pure stands of Bt corn and “RIB” plantings. Occurrence of larvae and ear damage on Bt corn were significantly lower than on non-Bt plants and there were no significant differences between pure stands of Bt and “RIB” plantings across all trials. However, the limited numbers of live larvae in the pure stands of Bt plants were distributed non-randomly, suggesting a possibility of uneven expression of Bt proteins or elevated larval movement in the pure stands of Bt plants. Larval occurrence (3rd–5th instars) and ear damage on the refuge ears in “RIB” plantings were similar to or greater than found on ears of pure stands of non-Bt plants. However, more studies are needed to understand the effect of pollen movement on the full life cycle of H. zea before a final conclusion on the refuge function of RIB planting can be made. 相似文献
19.
Transgenically expressed Bacillus thuringiensis insecticidal-protein Cry1Ab was quantified in target tissues of insect feeding of several YieldGard® corn hybrids. The Cry1Ab protein is intended to protect corn plants from two economically important stem borers, Chilo partellus and Sesamia inferens. A total of seven YieldGard hybrids, all with MON810 event, were field-tested in a total of fourteen locations during the dry season (October–March) of 2005/2006 and wet season (May–October) of 2006. S. inferens and C. partellus oviposit on leaves of young corn plants, 15–60 days after emergence (DAE). The neonates initially feed by scraping the leaf lamina before migrating to bore into the stem. Thus high concentrations of Cry1Ab in whorl leaf and stem tissues would ensure effective control of the borers. The mean tissue Cry1Ab concentrations during the oviposition window of the borers (15–60 DAE), ranged from 50.05 to 21.01 ppm in whorl leaf, and between 9.26 and 3.47 ppm in stem tissue during the same period in the dry season of 2005/06. Similarly, Cry1Ab concentrations in whorl leaf and stem between 15 and 60 DAE during the wet season of 2006 ranged between 19.30 to 11.08 and 14.28 to 4.69 ppm, respectively. The baseline-sensitivity data of these insects to Cry1Ab in laboratory assays was determined. The concentrations of Cry1Ab in the target tissues as studied in seven YieldGard hybrids tested suggest effective management of the two borers. This paper also provides a summary of the expression of the Cry1Ab gene in various genetic backgrounds. 相似文献
20.
种植密度对甜玉米与鲜食糯玉米产量与品质性状的影响 总被引：3，自引：0，他引：3
采用田间试验的方法,研究低密度(3.5万株/hm2,LD)、中密度(5.5万株/hm2,MD)、高密度(6.5万株/hm2,HD)种植对甜玉米(520)、糯玉米(吉农糯112)商品品质、食用品质以及部分营养品质的影响。结果表明,种植密度对鲜食玉米商品品质的影响较大,高密度种植会显著降低有效穗长、出籽率以及百粒重等商品性状。甜玉米皮渣率以及糯玉米的种皮厚度受种植密度影响较大,高密度处理下甜玉米(520)的皮渣率比低密度处理增加29.2%,糯玉米(吉农糯112)种皮厚度下降24.78%。种植密度对脂肪、可溶性总糖以及赖氨酸含量的影响不显著,显著影响鲜食玉米子粒中蛋白的含量,高密度处理下甜玉米(520)与糯玉米(吉农糯112)蛋白含量比低密度处理分别降低近1个百分点。 相似文献