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1.
ADVISORJIAORui Shen (J .S .Chao)  Professor(InstituteofPlantPhysiologyandEcology ,ShanghaiInstitutesforBiologicalSciences ,ChineseAcademyofSciences ,Shanghai 2 0 0 0 32 ,China)EDITOR IN CHIEFYANGSheng Li  Academician(ShanghaiResearchCenterforBiotechnology ,ChineseAca…  相似文献   

2.
宁南山区灌溉农业立体复合种植生态系统生产力的研究   总被引:1,自引:0,他引:1  
宁南山区灌溉农业立体复合种植生态系统生产力的研究杜守宇田恩平,王占山(宁夏农业技术推广总站,银川750001)(固原县农业技术推广中心,756000)StudyonProductivityofIrrigatedStereoscopicMultiple-CroppingEcosystemsinMountainousAreaofSouthernNingxia¥DuShouyu(CelleralStationofAgriculturalTechniqueExtensionofNingxia,Yinchuan750001),TianEnping,WangZhanshan(AgriculturalTechniqueExtensionCenterofCuyuancounty,756000).ChineseJournalofEcology,1993.12(6):11-16.ThevariouscroppingecosystemsareassessedcomprehensivelyforbenefitbytheanalysisofHierarchicalprocedureandtheexpectedbeneficialva  相似文献   

3.
丘陵地区农户生态系统演替分析   总被引:1,自引:1,他引:1  
丘陵地区农户生态系统演替分析曹凑贵(华中农业大学,武汉430070)EvolutionaryAnalysisonHousekoldEcosysteminHIIIyRegions¥CaoCougui(CentralChinaAgriculdturalUniversity,Wuhan430070).ChineseJournalofEcology,1993,12(2):53-54.Thecharacteristicsofdifferenttypehouseholdecosystemsandtheirevolutionarycorrelationsareanalyzedusingfuzzyclusteringandsystemsyntheticevolutionmethods,Thecauseanddirectionofagriculturaldevelopmentinhillyregionsarerevealedandsuggestionsondevelopingeco-agriculturalconstructioninlowerproductivehillyregionsaremade.Keywords:ho  相似文献   

4.
DVISORJIAORui Shen (J .S .Chao)  Professor(InstituteofPlantPhysiologyandEcology ,ShanghaiInstitutesforBiologicalSciences ,ChineseAcademyofSciences ,Shanghai 2 0 0 0 32 ,China)EDITOR IN CHIEFYANGSheng Li  Academician(ShanghaiResearchCenterforBiotechnology ,ChineseAcad…  相似文献   

5.
面向21世纪的中国生态学   总被引:4,自引:0,他引:4  
陈涛 《生态学杂志》1996,15(6):68-70
面向21世纪的中国生态学陈涛(中国科学院沈阳应用生态研究所,110015)EcologyTowards21stCenturyinChina.ChenTao(InstituteofAppliedEcology,ChineseAcademyofScien...  相似文献   

6.
里骆林区常绿阔叶林和人工杉木林气候水文效应   总被引:11,自引:2,他引:11  
里骆林区常绿阔叶林和人工杉木林气候水文效应黄承标,文受春(广西农学院林学分院南宁530001)(广西龙胜县林业局541700)ClimaticandHydrologicalEffectsofEvergreenBroad-leavedandArtificialChineseFirForestsinLiluoForestedRegion¥HuangChengbiao(ForestryCollege,CuangxiAgriculturalUniversity,Nanning530001),WenShouchun(ForestryBureau,LongshengCounty,Guangxi541700);ChineseJournalofEcol-ogy,1993,12(3):1-7.Siteinvestigationsandresearchesin1980-1990showthatevergreenbroad-leavedandartificialChinesefirfOrestsinLiluoforestedregioncanreducethevariationrangeofatmosphericandsoilt  相似文献   

7.
DetectionandAnalysisofanEstrous-associatedOviductalGlycoproteinDNAFragmentfromPrimatesbyPCR¥CHENQing-xuan(陈清轩);ClaytonE.Walto...  相似文献   

8.
Emergy Synthesis of the Environmental Resource Basis and Economy in China   总被引:5,自引:1,他引:4  
EmergySynthesisoftheEnvironmentalResourceBasisandEconomyinChinaLanShengfang(Dept.ofBiology,SouthChinaAgric.Univ.,Guangzhou510...  相似文献   

9.
SYSTEMATICPALEONTOLOGYGenusCelsigondolellaKozur ,196 8  Typespecies Gondolella (Celsigondolella)watznauriKozur ,196 8Celsigondolellabaiyunensissp .nov .(PlateⅠ ,figs .1— 5 )  Etymology NamedfromitsoccurrenceinBaiyunsection ,Guizhou .Diagnosis ArepresentativeofCelsiog…  相似文献   

10.
中国对虾cDNA文库的构建   总被引:26,自引:0,他引:26  
中国对虾cDNA文库的构建CONSTRUCTIONOFcDNALIBRARYOFSHRIMPPENAEUSCHINENSIS(CRUSTACEA,DECAPODA)关键词中国对虾cDNA文库构建KeywordsPenaeuschinensis,cDN...  相似文献   

11.
Wheat, cotton, and peanut were arranged in three cropping sequences to determine the effects of fenamiphos (6.7 kg a.i./ha) and cropping sequence on nematode population densities and crop yields under conservation tillage and irrigation for 6 years. The cropping sequences included a wheat winter cover crop each year and summer crops of cotton every year, peanut every year, or cotton rotated every other year with peanut. The population densities of Meloidogyne spp. and Helicotylenchus dihystera were determined monthly during the experiment. Numbers of M. incognita increased on cotton and decreased on peanut, whereas M. arenaria increased on peanut, and decreased on cotton; both nematode species remained in moderate to high numbers in plots of wheat. Root damage was more severe on cotton than peanut and was not affected by fenamiphos treatment. The H. dihystera population densities were highest in plots with cotton every summer, intermediate in the cotton-peanut rotation, and lowest in plots with peanut every summer. Over all years and cropping sequences, yield increases in fenamiphos treatment over untreated control were 9% for wheat, 8% for cotton, and 0% for peanut. Peanut yields following cotton were generally higher than yields following peanut. These results show that nematode problems may be manageable in cotton and peanut production under conservation tillage and irrigation in the southeastern United States.  相似文献   

12.
The efficacy of ''Deltapine 90'' cotton (Gossypium hirsutum) in rotation with ''Florunner'' peanut (Arachis hypogaea) for the management of Meloidogyne arenaria was studied for 2 years in a field in southeastern Alabama. In 1985, M. arenaria juvenile populations in plots with cotton were 98% lower than in plots with peanut. Peanut and cotton yields were increased by treatment with aldicarb (3.3 kg a.i./ha in a 20-cm-band) in 1985 but not in 1986. In 1986, peanut yields were highest and M. arenaria juvenile populations in soil were lowest in plots that had cotton the previous year. In 1986, numbers of M. arenaria juveniles in plots with peanut both years were reduced by treatment with aldicarb to levels found in plots with cotton-peanut rotation. The use of aldicarb in peanut following cotton similarly treated reduced the incidence of southern blight (Sclerotium rolfsii). Cotton-peanut is a good rotation for the management of M. arenaria and to increase peanut yields without the use of nematicides.  相似文献   

13.
Field cage experiments were conducted to determine the impact of bollworms, Helicoverpa zea (Boddie), on yields of Bollgard II and Widestrike cotton, Gossypium hirsutum L. One-day-old bollworm larvae were infested in white flowers of Bollgard II and in white flowers and terminals of Widestrike cotton. The infestation levels included 0, 50, and 100% of white flowers for each type of cotton. Terminal infestations included one or two larvae per terminal on Widestrike cotton. Larvae were placed in flowers of Bollgard II cotton each day for 1 to 4 wk during the first 4 wk of flowering during 2003, 2004, and 2005 seasons and in the flowers or terminals of Widestrike cotton each day for 1 to 3 wk. Averaged across years and durations of infestation, yields of Bollgard II cotton were significantly reduced compared with noninfested Bollgard II cotton when 100% of white flowers were infested. For Widestrike cotton, there was a reduction in yield when 100% of white flowers were infested in 2005, but not in 2006. There was a significant relationship for cumulative numbers of white flowers infested on seedcotton yield of Bollgard II during one of the 3 yr of the experiment. The regression equation during that year had a slope of -0.77. No significant relationships were observed for cumulative numbers of white flowers infested on yields of Widestrike cotton. Results of the current experiment suggest bollworms will rarely cause yield losses of Bollgard II and Widestrike cotton. Future research will need to focus on developing specific thresholds for bollworms on Bollgard II and Widestrike cotton.  相似文献   

14.
Triticale cv. Beagle 82, cotton cv. McNair 235, and soybean cv. Twiggs were arranged in three cropping sequences to determine the effects of fenamiphos and cropping sequence on nematode population densities and crop yields under conservation tillage for 4 years. The cropping sequences were triticale (T)-cotton (C)-T-C, T-soybean (S)-T-S, and T-C-T-S. Numbers of Meloidogyne incognita second-stage juveniles declined on trificale but increased on cotton and soybean each year. Root-gall indices of cotton and soybean ranged from 1.00 to 1.08 (1 to 5 scale: 1 = 0%, 2 = 1% to 25%, 3 = 26% to 50%, 4 = 51% to 75%, and 5 = 76% to 100% of roots galled) each year and were not affected by fenamiphos treatment or cropping sequence. Numbers of Pratylenchus brachyurus were maintained on trificale and generally increased more on soybean than on cotton. Population densities of Helicotylenchus dihystera were near or below detection levels in all plots during the first year and increased thereafter in untreated plots in the T-C-T-C and T-S-T-S sequences. Generally, yields of triticale in all cropping sequences declined over the years. Yields of cotton and soybean were not affected by fenamiphos at 6.7 kg a.i./ha. Cotton and soybean were grown successfully with little or no suppression in yields caused by nematodes in conservation tillage following triticale harvested for grain.  相似文献   

15.
棉铃虫与棉花生长发育耦合系统的建立   总被引:2,自引:0,他引:2  
以棉铃虫取食模型、种群动态模型及棉花生长发育模型为基础,通过对棉田生态系统中一些关键环节的分析,进一步发展出田间棉铃虫的管理系统。这个系统较好地反映出了国内外到目前为止在棉铃虫管理方面的最新研究成果。强调了在棉花生长发育过程中超补偿机制的实现,以及人工去早蕾与2代棉铃虫取食对棉花生长和产量形成的影响。本系统可以反映第2、3代棉铃虫不同卵量水平下,及不同人工去早蕾水平下棉花生长发育的动态过程。通过不同卵量水平时各去蕾量对产量的影响,以及不同用药时间的最终产量效果的比较,可以找出最佳的去蕾量以及合理的用药时间。  相似文献   

16.
Granular and liquid commercial humates, with micronutrients, and a microbial fermentation product were compared in several combinations with nematicides for their effects on cotton lint yield and root-knot nematode suppression. Fumigant nematicides effectively reduced cotton root galling caused by root-knot nematodes, and cotton lint yields increased. Organophosphates and carbamates were not effective. Occasionally, cotton lint yields were increased or maintained with combination treatments o f humates, micronutrients, and a microbial fermentation product, but galling o f cotton roots by root-knot nematodes was usually not reduced by these treatments.  相似文献   

17.
Subsoiling to a depth of 35 cm under the planting row for 3 consecutive years increased annual yields of seed cotton by 50 to 200%. Annual subsoiling was essential for maximum yields. The application of a nematicide, 1,2-dibromo-3-chloropropane (DBCP) or aldicarb, reduced the population of Hoplolaimus columbus but did not increase seed-cotton yields over subsoiling alone. Subsoiling reduced H. columbus in the top 20 cm of soil since the treatment favored deeper penetration by much of the root syslem and, consequently, less root colonization of the upper soil zone.  相似文献   

18.
Various insecticide use strategies including rotations, sequential use, and mixtures were evaluated experimentally on Bemisia tabaci (Gennadius) in California and Arizona (U.S.A.) cotton fields. Toxicological responses of adult B. tabaci were measured along with preimaginal densities and cotton yields from plots subjected to different insecticide regimens. Weekly monitoring for susceptibility changes over ten consecutive weeks in four different trials failed to detect significant differences between sequential use and rotation regimens, nor in comparison to the control plots. There were, however, significant differences among study-site locations and between study years as well as significant within-season time effects. Relative infestations in insecticide-treated plots expressed as a percentage of preimaginal densities in control plots indicated that better control was obtained by all insecticide treatments in conjunction with higher susceptibility levels observed in the second year. Lower preimaginal densities of B. tabaci were measured in the rotation treatment in comparison to sequential treatments of endosulfan, chlorpyrifos, or amitraz, but all were less effective than sequential treatments of bifenthrin or the mixture of bifenthrin + endosulfan. Cotton lint yields were inversely related to B. tabaci densities, with highest yields in the bifenthrin and mixture plots and lowest yields in the control plots. Suppression of B. tabaci infestations in insecticide-treated plots relative to untreated control plots also improved under conditions of lower B. tabaci pressure. The increases in cotton yield and susceptibility to insecticides seen in the current study support the trend observed in the southwestern USA of improved management of B. tabaci despite continuing intensive use of insecticides.  相似文献   

19.
Advances in plant biotechnology and its adoption in developing countries   总被引:1,自引:0,他引:1  
Developing countries are already benefiting and should continue to benefit significantly from advances in plant biotechnology. Insect-protected cotton containing a natural insecticide protein from Bacillus thuringiensis (Bt cotton) is providing millions of farmers with increased yields, reduced insecticide costs and fewer health risks. Many other useful plant biotechnology products that can benefit poor farmers and consumers are in the research and development pipelines of institutions in developing countries, and should soon reach farmers' fields.  相似文献   

20.
A 3-year study was conducted to determine the effects of mepiquat chloride and N levels on yield and quality of cotton (Gossypium hirsutum L.). Mepiquat chloride (MC) treatments did not significantlyaffect yields; however, cotton lint yields (1980) were 688, 949, 1,011, and 1,045 kg/ha for N rates of 0, 45, 90, and 135 kg/ha, respectively. Nitrogen by MC interactions on yield were not significant for any of the 3 years. MC treatments reduced plant height for all N levels. Plant height averages over all N levels were reduced 15–33% by the addition of MC. The MC treatments significantly increased the percent of Ca and Mg in the cotton leaves on a dry-weight basis. Nitrogen concentrations of the leaves were not affected by MC treatments. Leaf N levels were not significantly affected by N fertilization in 1979, but leaf N levels in 1980 were significantly increased at the 90 kg N/ha rate when compared with the check treatment.  相似文献   

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