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1.
棉铃虫辐射不育效应研究   总被引:9,自引:2,他引:7  
本文报道了棉铃虫经辐照诱导的不育效应。用60 Co γ射线处理棉铃虫蛹,成虫的羽化率随着剂量的升高而降低,畸形率和死蛹率增加。不同时期辐照蛹对成虫羽化率有明显影响。棉铃虫辐射不育以采用羽化前2d 的老熟蛹辐照为好,其羽化率为86-54 % 。卵的不育率随剂量的升高而升高。根据F1 代辐射遗传不育效应的研究认为:棉铃虫当代亚不育剂量以300 Gy 为宜。  相似文献   

2.
桃小食心虫(Carposina sasakii Matsmura)是广受关注的检疫性害虫,为比较不同射线的辐照效应以及不同种群对辐照的耐受能力,采用60Coγ射线、5MeV X射线和6MeV X射线对老熟幼虫进行辐照处理,剂量为60、80、100、120、140和160 Gy,剂量率为2.55~5.5 Gy·min-1。辐照后经室内饲养,分析羽化率结果表明,随着剂量的增加羽化率显著降低,100%阻止羽化的剂量为160Gy。相同剂量辐照时,不同射线处理苹果种群老熟幼虫的校正死亡率间无显著性差异。相同剂量60Coγ射线处理苹果种群(第13代和第20代)和山楂种群(第6代)的老熟幼虫,校正死亡率也无显著性差异。使用POLO软件进行机率值分析,预测检疫辐照处理中普遍使用的最低吸收剂量ED99和ED99.9968,阻止成虫羽化的剂量值非常接近(ED99=152.4~159.2 Gy;ED99.9968=195.2~208.7 Gy)。由此说明,不同辐照源阻止桃小食心虫老熟幼虫羽化的生物学效应相同,不同种群对辐照的耐受性相同,继代饲养后辐照耐受性未发生变化。由于老熟幼虫为水果中最耐受的虫态,可建议采用200Gy作为桃小食心虫幼虫检疫处理的最低吸收剂量。  相似文献   

3.
利用昆虫辐射不育技术防治光肩星天牛的可行性   总被引:3,自引:0,他引:3  
路大光  康文等 《核农学报》2001,15(5):301-307
利用昆虫辐射不育技术防治光肩星天牛的适照时期为羽化后7-10d,适宜的辐照剂量为70-90Gy,剂量率为1.5Gy/min。田间纱笼释放试验表明,释放比为5:1可压低野生虫口数量。利用昆虫不育技术防治光肩星天牛的难点是人工饲养。  相似文献   

4.
辐射不育棉铃虫交尾习性和交尾竞争能力的观察   总被引:3,自引:0,他引:3  
对棉铃虫经300 Gy γ射线照射后的成虫交尾习性和性竞争能力进行了观察。结果表明,在室内饲养条件下,棉铃虫成虫的交尾时间大多在清晨4 ~7 时,少数在凌晨2 ~3 时或早上8 ~9 时,较田间野生种群在时间上延后25h 左右。不育虫的交尾习性和交尾竞争能力与正常虫无明显差异,但不育虫的有效交尾率为616 % , 与正常虫相比减少1/3 。辐射不育棉铃虫一生交尾次数大多为1 次,少数达2 ~3 次,最多达5 次,可认为辐照不会改变其多配性的特点。辐射不育技术作为棉铃虫综合防治的措施是可行的。  相似文献   

5.
利用昆虫辐射不育技术防治光肩星天牛的可行性(英文)   总被引:1,自引:5,他引:1  
利用昆虫辐射不育技术防治光肩星天牛的适照时期为羽化后 7~ 1 0d ,适宜的辐照剂量为 70~ 90Gy,剂量率为 1 5Gy min。田间纱笼释放试验表明 ,释放比为 5∶1可压低野生虫口数量。利用昆虫不育技术防治光肩星天牛的难点是人工饲养  相似文献   

6.
本文研究了桃小食心虫(Carposina nipponensis Wals.)的染色标记技术和不育成虫在田间的扩散规律。将Sudan Blue 670(Ⅱ)染料加入到桃小食心虫幼虫的人工饲料内染色标记桃小食心虫,试验结果表明:染料浓度500ppm是较适宜的剂量,不仅使其幼虫、蛹、成虫及F_1代卵均匀染上蓝色,而且使精苞也染上浅蓝色,对桃小食心虫也无不良影响。采用释放染色标记虫及性诱剂诱捕技术研究桃小食心虫不育成虫的田间扩散规律,结果表明:不育虫在果园内的运动方向是随机的,80%集中在距释放点100米为半径的环域内,最远距释放中心225米,扩散密度与扩散距离有明显的回归关系,符合模型N=-0.67+402.45/X。  相似文献   

7.
辐射不育野蚕的释放比例及其田间防治的综合效果   总被引:1,自引:0,他引:1  
试验表明,辐射不育野蚕的田间释放比应为16:1 ̄20:1,此释放比经济有效,其防治效果:第1 ̄2代为77.21%,第3代达82.35%。由于大量收购田间采集的蛹作为田间释放不育蛹的虫源,收集区的防治效果达61.8%。两种方法相结合可取得双重防治效果,为防治野蚕开创了新途径。  相似文献   

8.
~(60)Coγ射线对印度谷螟的辐射遗传效应   总被引:1,自引:0,他引:1  
用~(60)Coγ射线1、3、5、7、10 krad辐照4~5日龄的印度谷螟雄蛹,当辐照剂量为1~7krad时,被辐照蛹都能羽化,但10krad辐照的,羽化率仅40%。用1、3 krad辐照,成虫畸形率低,且对雄成虫交配能力影响较小,但用7、10 krad辐照,成虫畸形率分别为60%、100%,只有30%~50%的成虫能进行交配。1、3、5 Krad辐照雄蛹,F_1代卵孵化率分别比对照降低25.5%、21.1%、39.4%,F_2代卵的孵化率分别比对照降低56.6%、80.8%、74.0%。这可能是遗传不育现象。1、5、7 krad辐照的,诱导出了成虫翅透明的突变品系(透明型)。该突变品系对研究印度谷螟的部分遗传学及遗传防治有重要意义。  相似文献   

9.
采用糖醋液和活雌蛾的方法诱集回收野蚕雄蛾,研究辐射不育野蚕雄蛾的田间扩散能力。试验表明,该回收方法可以使田间释放的野蚕雄蛾的回收率达12.6%-13.5%,不育野蚕雄蛾在24h内,90.8%扩散在距释放中心半径内15m的圆周内,覆盖面积达700m^2。据此,在用辐射不育法田间防治野蚕时,1hm^2桑地只需设立30个释放点就可满足防治的需要,达到较好的防治效果。  相似文献   

10.
300 Gy γ射线辐照棉铃虫( Helicoverpa ar m igera Hubner) 成虫( 棉田第1 代) 在田间的扩散试验表明:释放的标记虫约97 % 集中在离释放点半径720 m 的范围内。最远平均扩散距离为615 m 。棉铃虫扩散密度与扩散距离呈倒数相关,符合模型 N =- 083 + 164734/ x 。野生棉铃虫有向嫩绿寄主植物扩散的趋势。  相似文献   

11.
低氮和干旱胁迫对富士和秦冠生长及氮素利用的影响   总被引:2,自引:2,他引:0  
【目的】以富士(Fuji)、 秦冠(Qinguan)嫁接在平邑甜茶(Malus hupehensis Rehd.)上的当年生盆栽苗为试验材料,采用砂培方法,研究了缺氮胁迫和干旱对富士和秦冠生长情况、 光合参数、 植株各部位氮磷钾含量及氮素利用效率的影响,分析比较了低氮干旱条件下富士和秦冠生长及氮素利用的差异,以期为果树生产高效肥水利用提供理论指导。【方法】试验共设四个处理: 正常氮正常水(ZZ)、 低氮正常水(DZ)、 正常氮干旱(ZG)、 低氮干旱(DG)。氮素和水分均设置两个水平,分别为正常氮(6 mmol/L NO-3-N)、 低氮(0.3 mmol/LNO-3-N)、 正常供水(保持盆中砂子相对含水量为饱和含水量的80%~85%)、 干旱处理(保持盆中砂子相对含水量为饱和含水量的60%~65%)。【结果】富士和秦冠的生物量(茎和叶)、 株高茎粗等生长指标以及光合速率、 气孔导度、 蒸腾速率均为正常氮正常水(ZZ)>低氮正常水(DZ)>正常氮干旱(ZG)>低氮干旱(DG),并且相对应处理下秦冠的以上指标均高于富士;正常供水下,缺氮处理使富士、 秦冠的根冠比比正常氮处理均有所增加,富士提高了2.05%,秦冠提高了22.40%。富士和秦冠的氮、 磷、 钾含量均表现出正常氮正常水(ZZ)>低氮正常水(DZ)>正常氮干旱(ZG)>低氮干旱(DG); 氮、 钾元素含量在植株各部位的分布顺序依次是叶>根>茎,磷元素则是根>叶>茎;光合氮素利用效率(PNUE)和氮素利用效率表现为秦冠处理之间差异极显著,富士处理之间差异不显著;秦冠的PNUE和NUE明显高于富士,在低氮正常水(DZ)处理下,秦冠氮肥利用率比富士高42.07%,在低氮干旱(DG)处理下高64.14%;低氮胁迫下富士和秦冠的NUE显著提高,并且秦冠提高的幅度高于富士。【结论】施用氮肥能够显著提高富士与秦冠的干物质量,同等水肥条件下,秦冠生长优于富士;水分亏缺会减少叶片对氮的吸收,干旱条件下适度增施氮肥,可提高果树的抗旱能力;低氮干旱胁迫下秦冠的生长指标、 光合指标及氮素利用效率指标均优于富士,表现出较强的抗低氮干旱胁迫的能力。  相似文献   

12.
Staff members of the Department of Botany of Palacký University in Olomouc and Gene Bank Department – Workplace Olomouc, Research Institute of Crop Production in Prague, Czech Republic, conducted an expedition in seven European countries (Austria, Czech Republic, France, Germany, Italy, the Netherlands, Switzerland) in August/September 1999 to collect wild Lactuca spp. germplasm and study its geographic distribution, ecology and biodiversity. During the mission, more than 600 locations were visited resulting in the collection of 602 seed samples (accessions) of wild Lactuca species and 13 seed samples of related genera (Chondrilla and Mycelis). Lactuca serriola f. serriola, L. serriola f. integrifolia, L. saligna and L. viminea subsp. chondrilliflora were prevalent in southern Europe (Italy, France), however, only L. serriola was common in central and western Europe (Austria, Czech Republic, Germany, Netherlands, Switzerland). The greatest diversity of Lactuca species was found in France, where also the most seed samples (165) were collected. The most characteristic habitats with a high density of Lactuca spp. populations were observed along roads and highways, grassy ditches, ruderal communities, and dust-heaps. Natural infections by powdery mildew (Erysiphe cichoracearum) and downy mildew (Bremia lactucae) on some wild Lactuca spp. were observed. Recent observations concerning the geographic distribution, population structure, habitats, and natural occurrence of diseases of Lactuca spp. are discussed. This assemblage of genetic resources of Lactuca spp. can serve as the basis of future studies of species diversification, spatial population structure, plant microevolution, domestication processes, and genetic variability of host-parasite interactions.  相似文献   

13.
Laser-induced breakdown spectroscopy (LIBS) is a new technique for the analysis of plant material. This study investigates the application of LIBS to pasture-based plant samples. The LIBS measurements were obtained from pelletized pasture samples (100 samples) that had been also analyzed by inductively coupled plasma–optical emission spectroscopy (ICP-OES) following microwave digestion for calibration and comparison purposes. Comparisons for elements sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), boron (B), phosphorus (P), and sulfur (S) showed that LIBS could be used for almost all the standard profile total elements with concentrations down to low mg/kg levels (observed error of Na: 0.024 percent, K: 0.18 percent, Mg: 0.016 percent, Ca: 0.073 percent, P: 0.017 percent, Mn: 31 mg/kg, Fe: 150 mg/kg, Zn: 6.6 mg/kg, and B: 1.1 mg/kg). Elemental analysis at less than mg/kg levels was not possible using LIBS. The elements S and Cu were particularly difficult to analyze with reliability using LIBS at the concentration levels found in the plant samples. Replacing microwave digestion and subsequent ICP analysis with a direct analysis of dried plant samples using LIBS has the potential to improve the productivity and reduce the cost of testing.  相似文献   

14.
We have studied the effect of anaerobically digested (ADMSW) and composted municipal solid waste (CMSW) on mineralization and foodweb dynamics to verify the hypothesis that ADMSW would immobilize N right after addition to soil in contrast to addition with CMSW. Another hypothesis was that the mesofauna (enchytraeids and microarthropods) would stimulate N release from the decomposer community. We measured excretion of -N and urea-N from the mesofauna and hypothesized that enchytraeids would release urea. ADMSW and CMSW were amended to pots with sandy loam and barley. The pots were divided into treatments with or without mesofauna. Mesofauna, plant N and biomass, soil N and ergosterol (fungal biomass) were measured over a 113-day period of four equidistant samplings. Soil respiration, N mineralization and N release by the mesofauna were modelled from concurrent studies. ADMSW- and CMSW-treated soils initially (<20 days) immobilized N. The amendments did not increase plant growth substantially, and this was probably due to N-limitation in the early stages of plant growth. Enchytraeid abundance was about three times higher in ADMSW- than CMSW-treated soils, indicating that ADMSW contained more labile compounds, bacteria, and microfauna. The mesofauna did not affect N-content, but the cumulated -N excreted by the mesofauna was estimated to be substantial and about one-fifth of total plant N in ADMSW. An explanation for this discrepancy might be that in the absence of the mesofauna, other members of the detrivore and microbivore community performed the mesofauna’s function. Neither enchytraeids nor microarthropods excreted urea.  相似文献   

15.
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,  相似文献   

16.
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,  相似文献   

17.
“Wicked” problems are those that are complex and that change when solutions are applied. Many conflicts in conservation fall into this category. The study approached the problem of how to constrain the apparent wickedness of a problem in the conservation management of a species by using simple empirical indicators to carry out iterative assessment of the risk to a population and to document how this risk evolves in relation to the addition of new data and the implementation of management actions. Effects of high levels of uncertainty within data and also concerning population structure were examined through stochastic simulation and by exploration of scenarios. Historical trends in the example used, the Steller sea lion, showed rapid declines in abundance in some regions during the 1980s. The current total population is 130,000-150,000 Steller sea lions through Alaska and British Columbia and this number has been stable since about 1990 in spite of regional differences in population dynamics. Regional differences in the sequence of changes in the number of pups and non-pups, suggested that an internal re-distribution of juveniles could have happened between 1980 and 1990. Current productivity also appears close to the long-term mean. Stochastic population projection using various scenarios showed that, based upon this history, the risk of extinction for the population has declined and is below reasonable thresholds for considering the population to be endangered. The trends in risk suggest that management actions taken since 1990 have probably been effective. Consequently, the conservation management objectives for the Steller sea lion are probably being met. The approach provides a mechanism, based upon experience and scenario analysis, for exploring future policy options and may help to constrain the debate amongst stakeholders about the cost-benefit trade-offs associated with different options.  相似文献   

18.
Nutrient distributions under no tillage (NT) compared with conventional disk-and-bed tillage (CT) management in the warm, humid region of the southeastern USA need to be assessed so that future placement, quantity, and type of fertilizers can be altered, if necessary, to efficiently match crop demands. We determined soil-profile distributions of pH, N, P, S, K, Ca, Mg, Na, Zn, Fe, Mn, and Cu to a depth of 0.9 m at the end of 8.5 years of continuous CT and NT management on a Weswood silty clay loam (fine, mixed, thermic Fluventic Ustochrept) in southcentral Texas. Most dramatic changes occurred within the 0–0.05 m depth, where soil under NT had lower pH, Fe, and Cu than under CT, but greater P, K, Zn, and Mn. Greater P and K under NT than under CT also occurred below the till-zone (0.15–0.3 m). At a depth of 0–0.3 m, soil under NT contained greater amounts of extractable P, K, Zn, Fe, Mn, and Cu than under CT. Nitrogen fertilization had little effect on nutrient distributions, except resulting in greater extractable K at 0–0.05 m and greater nitrate at 0–0.15 m. Few changes in soil-profile distributions were observed for extractable S, Ca, Mg, and Na. Long-term continuous use of NT on this fine-textured, high-fertility (except for N) soil had no apparent adverse effects on nutrient distributions relative to CT, but enhanced conservation and availability of P, K, Zn, Fe, Mn, and Cu near the soil surface where crop roots proliferate.  相似文献   

19.
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,  相似文献   

20.
The responses of tallgrass prairie plant communities and ecosystem processes to fire and grazing are well characterized. However, responses of invertebrate consumer groups, and particularly soil-dwelling organisms, to these disturbances are not well known. At Konza Prairie Biological Station, we sampled soil macroinvertebrates in 1994 and 1999 as part of a long-term experiment designed to examine the effects and interactions of annual fire, mowing, and fertilization (N and P) on prairie soil communities and processes. For nearly all taxa, in both years, responses were characterized by significant treatment interactions, but some general patterns were evident. Introduced European earthworms (Aporrectodea spp. and Octolasion spp.) were most abundant in plots where fire was excluded, and the proportion of the total earthworm community consisting of introduced earthworms was greater in unburned, unmowed, and fertilized plots. Nymphs of two Cicada genera were collected (Cicadetta spp. and Tibicen spp.). Cicadetta nymphs were more abundant in burned plots, but mowing reduced their abundance. Tibicen nymphs were collected almost exclusively from unburned plots. Treatment effects on herbivorous beetle larvae (Scarabaeidae, Elateridae, and Curculionidae) were variable, but nutrient additions (N or P) usually resulted in greater densities, whereas mowing usually resulted in lower densities. Our results suggest that departures from historical disturbance regimes (i.e. frequent fire and grazing) may render soils more susceptible to increased numbers of European earthworms, and that interactions between fire, aboveground biomass removal, and vegetation responses affect the structure and composition of invertebrate communities in tallgrass prairie soils.  相似文献   

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