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1.
BACKGROUND: The Colorado potato beetle (CPB), Leptinotarsa decemlineata Say, is a destructive pest. The CPB is a quarantine pest in China, but has now invaded the Xinjiang Uygur Autonomous Region and is continuing to spread eastwards. To control the damage and overspreading, transgenic potato plants expressing Cry3A toxin were developed, and their resistance to CPB was evaluated by bioassays in the laboratory and field in 2009, 2010 and 2011. RESULTS: The insect resistance of the high‐dose (HD) transgenic lines was significantly greater than the middle‐dose (MD) and low‐dose (LD) transgenic lines regarding leaf consumption, biomass accumulation and mortality. The HD and MD transgenic lines showed 100% mortality when inoculated with first‐ and second‐instar larvae; however, the LD transgenic lines showed about 50% mortality. The HD transgenic lines exhibited a significantly higher yield than the MD and LD transgenic lines owing to their high CPB resistance. CONCLUSION: Commercially available transgenic potato plants with above 0.1% Cry3A of total soluble protein and NT control refugia could control damage, delay adaptation and halt dispersion eastwards. The two HD transgenic lines developed in this study, PAH1 and PAH2, are ideal for use as cultivars or germplasm to breed new cultivars. Copyright © 2012 Society of Chemical Industry  相似文献   

2.
为明确花生-玉米间作种植模式对蓟马类害虫的控制效果,通过3年田间试验系统调查花生单作、玉米单作和花生-玉米间作3种种植模式下蓟马及其主要捕食性天敌东亚小花蝽Orius sauteri的种群数量动态特征及不同种植模式下东亚小花蝽和蓟马的益害比。结果显示,花生-玉米间作种植模式下东亚小花蝽种群密度显著高于花生单作种植模式,花生-玉米间作种植模式下82.94%以上的东亚小花蝽来源于玉米斑块;与2种单作种植模式相比,花生-玉米间作种植模式未显著减少蓟马的种群密度;东亚小花蝽种群密度与蓟马种群密度呈显著线性关系;花生-玉米间作种植模式下东亚小花蝽与蓟马的益害比均显著低于其他2种单作种植模式。表明花生-玉米间作种植模式在局域农田小范围空间尺度下能显著提高捕食性天敌的种群密度,但并不能显著减少蓟马类害虫种群数量。  相似文献   

3.
A crop rotation field study was conducted in 1981–1989 to assess the effect of six crop rotation sequences on a soil population of potato cyst nematode (PCN), Globodera rostochiensis, and on potato yield. In the plots with potato monoculture, the tuber yield decreased from 35 to 4.6 t ha?1. All other cropping systems maintained the yield at the original or an even higher level. In monoculture, the population density of the nematode was raised during the first 3 years from 0.1 to 265 larvae g?1 soil, and the density fluctuated afterwards between 30 and 136 larvae g?1 soil. Three of the cropping systems, (1) susceptible potato once in 5 years, (2) susceptible potato once in 4 years, and (3) potato once in 3 years using resistant (H1) and susceptible cultivars alternately, decreased the nematode density under the economic threshold or even under the level of detection. The nematicide treatments (oxamyl) did not control nematode multiplication but prevented yield losses. No nematicide is currently registered nor needed for the control of PCN in Finland. The nematode can be controlled effectively with crop rotation, resistant cultivars and early harvesting.  相似文献   

4.
ABSTRACT A field study at three highland sites near Quito, Ecuador, was conducted to determine whether host-diversity effects on potato late blight would be as important as recently found in studies conducted in temperate areas. We compared three potato mixtures and use of mixtures in combination with different planting densities and two fungicide regimes. Treatment comparisons were made by absolute and relative measures of host-diversity effects and incorporating a truncated area under the disease progress curve as a means of standardizing comparisons across sites. Potato-faba intercrops consisting of only 10% potato provided an estimate of the effects of dilution of susceptible host tissue. Host-diversity effects were very different across study sites, with a large host-diversity effect for reduced disease only at the site most distant from commercial potato production. Planting density had little influence on host-diversity effects or on late blight in single-genotype stands. Fungicide use in combination with potato mixtures enhanced a host-diversity effect for reduced late blight. Potato-faba intercrops produced only a small decrease in potato late blight. Effects of host diversity on yield were variable, with the greatest increase in yield for mixtures treated with fungicides at the site most distant from commercial potato production. The effects of host diversity on late blight severity may be less consistent in the tropical highlands than in the temperate zone, but can contribute to integrated disease management.  相似文献   

5.
BACKGROUND: Increasing attention has been paid to enhancing biological control through habitat management in agricultural systems for enhanced pest management. Pest management benefits can be realised by intercropping, which can increase natural enemy abundance and, in turn, reduce pest abundance. In this study, the composition and temporal dynamics of arthropod communities in pear orchards when intercropped with aromatic plants were investigated, and the effectiveness and applicability of aromatic plants as intercrops for enhancing insect control were assessed. RESULTS: When compared with natural grasses or clean tillage, intercropping significantly reduced pest abundance and increased the ratio of natural enemies to pests. Intercropping also shortened the occurrence duration and depressed the incidence peak in annual dynamics curves of the pest subcommunity and the arthropod community, mainly because of the repellent effects of aromatic plants. Equally important, intercropping significantly reduced the numbers of major pests, such as Psylla chinensis, Aphis citricola and Pseudococcus comstocki, while their incidence period was delayed to varying degrees, and the numbers of their dominant natural enemies (Coccinella septempunctata, Phytoseiulus persimilis and Chrysoperla sinica) increased. CONCLUSION: Intercropping with aromatic plants led to a considerable improvement in arthropod pest management by enhancing the activity of the beneficial arthropod community within the pear orchard ecosystem. Copyright © 2011 Society of Chemical Industry  相似文献   

6.
苹果园混合覆盖植物对害螨和东亚小花蝽的影响   总被引:4,自引:0,他引:4  
苹果园种植紫花苜蓿,为捕食性天敌提供了适宜的生存环境和补充猎物,使苹果园天敌数量增加,叶螨种群下降。夏至草是苹果园杂草的优势种,该杂草可提供天敌生存所需的花粉、花蜜和猎物,使东亚小花蝽发生时间提早,发育速度加快。在6月中旬前,东亚小花蝽可在夏至草上完成2代,在紫花苜蓿上完成1代。夏至草与紫花苜蓿的比例变化影响苹果园节肢动物物种数量,当混合植被中夏至草的覆盖度大于25%时,对覆盖植物和苹果树冠捕食性天敌种群数量最为有利。夏至草与紫花苜蓿混合(1∶4),比单一紫花苜蓿上天敌的数量增加2~3倍,苹果树冠天敌数量增加70%,苹果叶螨种群数量降低30%  相似文献   

7.
分蘖洋葱与番茄伴生根系分泌物对根结线虫的影响   总被引:1,自引:0,他引:1  
为明确根系分泌物在番茄伴生分蘖洋葱Allium cepa var. agrogarum Don.体系中减轻番茄根结线虫病的作用,本研究以番茄Lycopersicon esculentum和分蘖洋葱为试材,通过双室试验及外源添加根系分泌物等方法,研究了根系分泌物对根结线虫死亡率、卵孵化率的影响以及根系分泌物对线虫的吸引率。结果表明,番茄单作-分蘖洋葱伴生番茄双室系统中,分蘖洋葱伴生处理的土壤中线虫数量比番茄单作处理减少68.0%(P<0.05);番茄单作-分蘖洋葱单作的双室系统中,分蘖洋葱单作处理的土壤中线虫数量比番茄单作处理减少69.0%(P<0.05)。外源添加单作分蘖洋葱根系分泌物、伴生分蘖洋葱根系分泌物以及伴生体系中番茄和分蘖洋葱的根系分泌物初期,线虫死亡率能够显著提高34.5%~39.0%,卵孵化降低22.0%~53.2%,对线虫的吸引率降低10.9%~37.0%。研究结果为揭示伴生分蘖洋葱根系分泌物在减轻番茄根结线虫病中的作用奠定了基础。  相似文献   

8.
Abstract

Major insect pests and their natural enemies were sampled on cowpea in monocrop and cereal intercrop plots in southern and northern Nigeria. Populations of flower thrips, Megalurothrips sjostedti (Trybom), were reduced by 42% and predators, mostly Orius spp. (Anthocoridae), by 23% on cowpea in maize intercrop plots at Ofiki in the south. Infestation by pyralid pod borer, Maruca testulalis Geyer, was unaffected by cropping system. The results suggest that tasselling maize attracts flower‐eating beetles (Meloidae) to intercrop plots, and that pod‐sucking Hemiptera were increased by cereal intercrops at Yankara in the north. Three u.l.v. applications of permethrin at 150 g a.i./ha to monocrop cowpea reduced pest populations by 50 to 85% in the south and increased yield sevenfold. However, the sprayed crop in the north was lost due to a heavy infestation of pod‐sucking bug, Clavigralla tomentosicollis Stål, and outbreaks of Aphis craccivora Koch on sprayed plots in both localities suggested damage to natural enemies. It is concluded that the pest management potential of intercropping is variable and dependent on environmental factors, but it is recommended that intercropping be used in integrated pest management systems with the progressive decrease in insecticide use.  相似文献   

9.
We examined whether the invasive silverleaf nightshade, Solanum elaeagnifolium (Cavanilles) can facilitate the infestation of potato (Solanum tuberosum (L.)) by the Colorado Potato Beetle, CPB, Leptinotarsa decemlineata (Say) in Greece, which would have important financial and pest management implications for the growing of potato crops. In laboratory tests, CPB from Lesvos could utilise S. elaeagnifolium if supplied with whole plants. In the field, however, CPB was only found on S. elaeagnifolium after the start of the spring potato harvest and the resulting loss of potato foliage, and no eggs were laid. This suggests that S. elaeagnifolium provides only a temporary food resource for adult beetles. One of 10 surveyed summer potato fields near the study population of S. elaeagnifolium was infested with CPB. It is likely that the presence of S. elaeagnifolium in the vicinity of spring and summer potato fields can help maintain CPB population viability in the immediate post harvest period of the spring potato crop, which may in turn facilitate the infestation of summer potato fields with CPB.  相似文献   

10.
试验选用生育期相近的4个水稻品种(津原45、津原11、津原17和花育409),通过等比例混播,研究水稻的遗传多样性对主要病虫害和天敌的发生以及产量的影响,在此基础上分析了各个参数之间的相关性。结果表明,水稻品种混播显著降低了褐飞虱Nilaparvata lugens Stal的种群密度,提高了捕食性蜘蛛的种群密度。混播比单播均值增产2.5%,比津原45单播增产17.3%。相关性分析表明,不同品种的产量因子与害虫及天敌的发生量之间相关性不同,津原45和津原11单播处理中各参数间相关性显著,而在混播处理中不显著。本试验支持了农业生物多样性对病虫害调控作用的理论,为水稻的安全生产提供了技术依据。  相似文献   

11.
Imperata cylindrica is a noxious weed that infests annual and perennial crops in most tropical regions. High crop densities may offer opportunities to reduce I. cylindrica competition in small‐scale farming systems. The competitive ability of maize relative to I. cylindrica was evaluated in an addition series experiment in the forest savannah transition zone in 2006 and 2007 at Ibadan, Nigeria. Maize and I. cylindrica were planted in eight monoculture densities (4, 8, 12, 16, 20, 32, 48 and 64 plants m?2) and in a 1:1 mixture at eight total densities (2:2, 4:4, 6:6, 8:8, 10:10, 16:16, 24:24 and 32:32 maize: I. cylindrica plants m?2) as in monoculture. Non‐linear regression models were used to relate crop and weed shoot biomass to their densities and total grain yield to maize density. In maize, intraspecific competition was more than interspecific competition; in I. cylindrica, interspecific competition was higher than intraspecific. As expected, total grain yield was lower in the mixture than in maize monoculture at all total densities. Average maize grain yield in maize monoculture differed from that in mixtures by 0.77 t ha?1 in 2006 and 0.57 t ha?1 in 2007. Niche differentiation indices were <1 in 2006 and >1 in 2007, indicating that both species competed for similar resources in 2006, but not in 2007. The greater competitive ability of maize over I. cylindrica may be associated with rapid growth and canopy development observed in the field.  相似文献   

12.
为了明确牛角花齿蓟马为害对紫花苜蓿生长及氮代谢的影响,测定了不同牛角花齿蓟马虫口密度下抗、感蓟马苜蓿无性系R-1、I-1的受害指数、单株生物量及氮代谢的变化。结果表明:(1)随着牛角花齿蓟马虫口密度的增加,R-1、I-1无性系各接虫处理的受害指数均升高、单株生物量均下降,在相同牛角花齿蓟马虫口密度下,R-1无性系的受害指数及产量损失率均低于I-1无性系。(2)受牛角花齿蓟马为害后,R-1无性系各接虫处理硝酸还原酶活性上升后趋于稳定,硝态氮含量呈先上升后下降的趋势,游离氨基酸含量呈持续上升的趋势; I-1无性系各接虫处理的硝酸还原酶活性呈先上升后下降的趋势,硝态氮含量呈先下降后上升的趋势,游离氨基酸含量上升后趋于稳定或下降。结果说明:硝酸还原酶活性的升高是R-1无性系对蓟马诱导抗性的一种表现,而I-1无性系氮代谢失调是其感蓟马的主要原因之一,因此R-1无性系的适应能力强,受害较轻,对牛角花齿蓟马为害的抗性和补偿生长能力高于I-1无性系。  相似文献   

13.
Biological Control of Alfalfa Weevil in North America   总被引:4,自引:0,他引:4  
Alfalfa weevil, Hypera postica (Gyllenhall) (Coleoptera: Curculionidae), is of Eurasian origin. This destructive pest of alfalfa (lucerne) was accidentally established in North America on three separate occasions. These introductions are commonly identified in the literature as biological strains: western alfalfa weevil, Egyptian alfalfa weevil (=Hypera brunneipennis Boheman), and eastern alfalfa weevil. Alfalfa weevil has been the target of classical biological control almost since its discovery in North America more than 90 years ago. These efforts have resulted in establishment of at least nine exotic parasitoids and egg predators: Bathyplectes curculionis (Thomson), B. anurus (Thomson) and B. stenostigma (Thomson) (Hymenoptera: Ichneumonidae); Microctonus aethiopoides Loan and M. colesi Drea (Hymenoptera: Braconidae), the latter of undetermined origin; Oomyzus incertus (Ratzenberg) (Hymenoptera: Eulophidae); Dibrachoides dynastes (Forester) and Peridesmia discus (Walker) (Hymenoptera: Pteromalidae); and Anaphes luna (Girault) (Hymenoptera: Mymaridae). A fungal pathogen, Zoophthora phytonomi Arthur (Phycomycetes: Entomophthoraceae), of undetermined origin, is becoming an increasingly important alfalfa weevil mortality factor. Most major USA alfalfa production areas now benefit from a complex of alfalfa weevil biological control agents. Collectively, these agents have effected substantial reduction in the economic importance of alfalfa weevil across the northern USA However, biological agents provide only partial control of alfalfa weevil, and importance of their contribution differs considerably with production area. Still, the benefits achieved, especially from reduced need for insecticides in alfalfa production, mark this as one of the great success stories of classical biological control in North America.  相似文献   

14.
间作对甜玉米田主要害虫与天敌动态的影响   总被引:7,自引:5,他引:2  
为明确甜玉米间作不同作物对害虫的控制作用,采用目测法系统调查了甜玉米单作、甜玉米与绿豆、菜豆、甘薯或花生间作生境玉米主要害虫和天敌种群发生动态,并比较了不同生境亚洲玉米螟的为害情况。间作生境中捕食性天敌蜘蛛和瓢虫类群的个体数量均明显增加,其中甜玉米间作绿豆或甘薯生境蜘蛛类群增长21%以上,瓢虫类群增长83%以上,显著高于甜玉米单作生境;不同生境间玉米螟赤眼蜂发生量差异不显著,对亚洲玉米螟卵的寄生率均达到86%以上。间作生境玉米生育期内亚洲玉米螟落卵量、斜纹夜蛾及玉米蚜发生量均与甜玉米单作无显著差异,但收获期甜玉米间作生境玉米螟为害率低于单作生境,其中以甜玉米间作绿豆生境最低,总蛀孔数和活虫数分别比单作生境下降55.72%和76.70%。表明间作不同作物对甜玉米田具有一定的控害增益作用。  相似文献   

15.
Summary This paper tests the hypothesis that increased soil nitrogen supply reduces the growth of late-emerging weeds in wheat and potato by enhancing canopy leaf area development and thereby reducing the availability of light for weed growth. Two series of experiments were conducted: one in spring wheat (1997, 1999) with sown Stellaria media and one in potato (1998, 1999) with naturally emerged weeds, including S. media . For each crop, two cultivars were grown at three levels of nitrogen supply. In wheat, as in a monoculture of S. media , total dry weight and seed number of the weed increased with soil nitrogen supply, whereas in potato the opposite was found. Increased soil nitrogen supply increased the nitrogen uptake of S. media in wheat, despite the reduced light availability, indicating that S. media in wheat was limited by nitrogen. In potato, on the other hand, growth of S. media was limited by light availability, which decreased with increased soil nitrogen supply . We conclude that the differences in response of S. media in wheat and potato to additional nitrogen supply are attributable to the dual influence of soil nitrogen supply on light and nitrogen availability, which are mediated by the crops.  相似文献   

16.

In the Central Plateau of Burkina Faso, runoff on bare soil amounts to 40% of annual rainfall and soil losses reach 4 to 8 Mg ha-¹ a-¹, despite slopes of under 3%. Several studies have shown that mulching the soil surface can reduce runoff by over 60%. However, the scarcity of straw and the incompatibility of mulching with mechanical soil preparation have prevented the large-scale adoption of the technique. The study conducted in Saria village where annual rainfall is 800 mm,set out to evaluate the efficacy of sorghum-cowpea intercropping in reducing runoff and erosion. The study design comprised five plots set up so as to recover runoff and transported solids, on a Ferric lixisol with a slope of 0.7%. Three years results showed that sorghum-cowpea intercropping reduces runoff by 20-30% compared to a sorghum monoculture and by 45-55% compared to a cowpea monoculture. Soil loss is also reduced with intercropping by at least a half compared to sorghumand cowpea monoculture. Moreover, it transpired that sorghum-cowpea intercropping is also beneficial in agricultural production terms, since the grain yield of the intercropped plots was double that obtained with sorghumor cowpea monocultures. The better crop production can be an asset for the widespread use of this technique in the country. An evaluation of the advantages of the legume in terms of nitrogen supplies to the cereal (N 2 symbiotic fixation) and of added soil OM will be useful in improving the cost-effectiveness of such a technique.  相似文献   

17.
近年来中国马铃薯晚疫病的时空演变特征及防控情况分析   总被引:1,自引:0,他引:1  
为系统全面地了解马铃薯晚疫病在我国的发生演变特征及防控情况,基于2008—2017年国家统计局官方数据、《中国农业统计资料》《全国植保专业统计资料》及全国马铃薯品种分布等数据,对全国及各马铃薯产区晚疫病的发生及防治情况进行综合量化分析。结果表明:马铃薯晚疫病在我国连年发生,年平均发生面积约197.47万hm2,占马铃薯总种植面积的40.66%;晚疫病造成马铃薯年平均产量损失占所有病害所致产量损失的63.54%,远高于其他病害,损失巨大;在我国马铃薯4大产区中,马铃薯晚疫病在北方一作区的年平均发生面积最大,约73.44万hm2,而在西南混作区造成的年平均产量损失最高,约14.29万t;晚疫病发生与马铃薯种植区域的重心在空间上呈现相似的迁移趋势;以费乌瑞它为代表的高感晚疫病品种在全国大面积种植,但近年来部分抗病品种的种植面积正在逐年增加;近年来我国对马铃薯晚疫病的防治面积大幅度提升,但仍太过依赖化学防治,应加大绿色防控技术的推广和应用力度。  相似文献   

18.
BACKGROUND: The potato psyllid is a serious pest of potatoes. Sampling plans on potatoes for the potato psyllid have yet to be developed, thus the authors' objectives were (1) to determine the most efficient within‐plant sampling unit, (2) to determine the spatial dispersion of potato psyllids in potato fields and (3) to develop a binomial sequential sampling plan for this pest. RESULTS: Significantly more potato plants were infested with potato psyllids on the edges of the field, and significantly more plants were infested with psyllids on the ‘top’ and ‘middle’ of the potato plant. Significantly more psyllids were also found on the undersides of leaves. The potato psyllid has an aggregated distribution in potato fields. Binomial sequential sampling plans were developed for three action thresholds representing 0.5, 1 and 5 psyllids per plant. The average sample numbers for these action thresholds were between 12 and 16 samples, depending on the action thresholds. However, based on the shape of the operating characteristic curve, the 0.5 and 1 sampling plans were more reliable than the 5 psyllids per plant plan. CONCLUSION: The binomial sequential sampling plans are useful for detecting potato psyllids at low levels of infestation, which will be useful for pest management purposes. Copyright © 2011 Society of Chemical Industry  相似文献   

19.
Action thresholds as decision tools for insecticide application were developed and tested against the major insect pests of rice at four sites in the Philippines over a 13-year period. Action threshold treatments were compared to the farmers' practice, prophylactic insecticide usage, and an untreated check. Yield loss data using the insecticide check method partitioned yield losses over three crop growth stages in the same test fields. Chronic pests that exceeded action thresholds in 79% of fields were whorl maggot Hydrellia philippina Ferino (Diptera: Ephydridae), defoliators Naranga aenescens Moore and Rivula atimeta (Swinhoe) (Lepidoptera: Noctuidae), leaffolders Cnaphalocrocis medinalis (Guenée) and Marasmia patnalis Bradley (Lepidoptera: Pyralidae), and stemborers Scirpophaga incertulas (Walker) and S. innotata (Walker) (Lepidoptera: Pyralidae). Minor chronic pests reached threshold levels in only one site each: rice bug Leptocorisa oratorius (F.) (Koronadal), whitebacked planthopper Sogatella furcifera (Horvath) (Zaragoza) and green leafhopper Nephotettix virescens (Distant) (Guimba); brown planthopper Nilaparvata lugens (Stål) did not exceed a threshold in any field. Stemborers were the most important pest group in terms of yield loss. Despite the insecticide check method underestimating losses, a mean crop loss of 0.62 t/ha was measured which showed ample scope for corrective action. But loss was evenly distributed across crop growth stages (0.15?–?0.24 t/ha) reducing the impact of insecticides. Action threshold treatments overall outyielded the untreated check, more so in the two sites with highest pest density. The benefit of thresholds was to reduce insecticide usage, as a cost saving. However all the practices showed poor economic returns including the farmers' practice. Farmers' practice employed low insecticide dosages and timing was not consistent with pest damage, but yields were often similar to threshold treatments. Farmers appear to use insecticide more for risk aversion than for profit. The best threshold characters when evaluated against resulting pest density and yield loss criteria showed accuracies >?90% correct decisions. Future work is needed to improve the insecticide response rather than monitoring tools. Thresholds need to be incorporated into improved crop management, which was often found suboptimal by farmers, to take advantage of the high levels of tolerance in modern high tillering cultivars. Crop husbandry practices which improve yield potential such as selection of longer maturing varieties and nitrogen fertilizer may be a more effective pest management strategy than insecticides.  相似文献   

20.
为探究肥料减施下玉米-大豆间作对作物产量和昆虫群落组成及多样性的影响,在玉米、大豆单作及二者间作下施以标准肥料750 kg/hm~2和减半肥料375 kg/hm~2,于作物生长期调查田间昆虫群落组成及多样性,并在收获期对玉米和大豆进行测产。结果表明:与单作玉米相比,间作玉米在施用标准肥料下的百株生物量、百株籽粒重和千粒重分别显著增加78.33%、85.35%和38.71%,而在施用减半肥料下则分别显著增加90.91%、135.73%和33.33%;相同种植模式下,与施用标准肥料相比,减半肥料使单作玉米百株籽粒重显著降低22.45%。与单作大豆相比,在施用标准肥料下,间作大豆的百株籽粒重和千粒重分别显著降低49.47%和11.54%,在施用减半肥料下,间作大豆的百株生物量、百株籽粒重和千粒重分别显著降低73.94%、50.51%和17.39%;相同种植模式下,与施用标准肥料相比,减半肥料使大豆在单作和间作下的百株籽粒重分别显著降低65.02%和65.73%,使间作下大豆的百株生物量和千粒重分别显著降低73.14%和17.39%。与单作相比,间作均显著降低了标准肥料和减半肥料处理下玉米和大豆害虫群落的物种数、多样性指数和均匀度指数,还显著降低了标准肥料和减半肥料处理下玉米天敌昆虫群落的物种数和优势度指数以及大豆天敌昆虫群落的物种数和均匀度指数。表明玉米-大豆间作能有效提高玉米产量,降低虫害发生,但对大豆生产不利,而间作条件下减施肥料对玉米产量的影响更小。建议在田间生产中可将夏玉米和大豆间作种植,更有利于通过生态学方法控制田间害虫发生和增加作物总体产量。  相似文献   

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