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21.
22.
为了研究狐貉粪对黑水虻幼虫生长、预蛹及蛹的发育、成虫历期、饲料系数的影响,在温度20~25℃、湿度70%~80%的环境下,以狐貉粪为主料,添加不同比例的基础料(麦麸、豆粕与玉米面)进行饲喂。结果表明:30%发酵混合料+70%基础料处理下,老熟幼虫、预蛹、蛹的质量分别为156.0、108.8、60.2 mg,显著高于对照组,预蛹历期、蛹历期分别为7、6 d,相较于对照组显著缩短;30%发酵混合料+70%基础料的黑水虻成活率、化蛹率、羽化率都较高,分别为93%、88%、91%;50%发酵混合料+50%基础料处理组除幼虫体重显著低于30%发酵混合料+70%基础料处理组外,其他指标差异均不显著。综合分析认为,30%~50%发酵混合料对黑水虻生长发育最为适宜。 相似文献
23.
粉煤灰基吸附剂吸附亚甲基蓝及再生性能研究 总被引:1,自引:0,他引:1
研究粉煤灰基吸附剂及微波辐照再生后吸附剂对亚甲基蓝的吸附行为,确定了粉煤灰基吸附剂达到吸附平衡的时间及吸附过程符合的等温吸附模型。试验结果表明,1 h后粉煤灰基吸附剂吸附基本达到平衡,吸附过程更符合Freundlich等温吸附模型,最大平衡吸附量为35.64 mg/g。对吸附饱和亚甲基蓝粉煤灰基吸附剂进行微波辐照再生研究,最佳的再生条件为微波功率700 W,再生时间2 min,粉煤灰基吸附剂再生效率为98.6%。 相似文献
24.
以粉煤灰、膨润土等制备新型粉煤灰陶粒,考察粉煤灰陶粒对溶液中Cu(Ⅱ)的去除特性并进行吸附等温线拟合.结果表明,粉煤灰陶粒对Cu(Ⅱ)的去除主要为吸附过程,对Cu(Ⅱ)的吸附效果与陶粒用量、温度及振荡速度有关,较大的粉煤灰陶粒用量、适宜的温度及振荡有较好的Cu(Ⅱ)去除效果.当温度为25℃、pH4.5及振荡速度150 r/min时,2.00 g粉煤灰陶粒对50 mL溶液中浓度为100 mg/L的Cu(Ⅱ)去除率为100%,而同等条件下两种普通市售陶粒的Cu(Ⅱ)去除率分别只有14.6%、6.3%.陶粒吸附柱可连续4次对250 mL浓度为100 mg/L的Cu(Ⅱ)去除率达90%以上.25℃时粉煤灰陶粒对Cu(Ⅱ)的最大吸附量为2.78 mg/g,其吸附过程符合Langmuir等温式,以Freundlich吸附等温式拟合则相关性较差. 相似文献
25.
P. Crisp 《Euphytica》1982,31(3):725-734
Summary A hypothetical scheme is given for the evolution of the different types of cauliflower (Brassica oleracea var. botrytis L.). This has been useful in identifying sources of reduced susceptibility to cabbage root fly (Delia radicum (L.)), and may also be useful in the search for reduced susceptibility to clubroot (Plasmodiophora brassicae Woron.). It is argued that knowledge of the phylogeny of types within each crop species is of great importance in the exploitation of genetic resources. 相似文献
26.
Summary Sorghum shoot fly, Atherigona soccata (Rondani) is an important pest of sorghum in Asia, Africa, and Mediterranean Europe, and host plant resistance is an important
component for the management of this pest. The levels of resistance in the cultivated germplasm are low to moderate, and therefore,
it is important to identify genotypes with different mechanisms of resistance to pyramid the resistance genes. We studied
the antixenosis for oviposition, antibiosis, and tolerance components of resistance in a diverse array of shoot fly-resistant
and -susceptible genotypes. The main plants and tillers of SFCR 151, ICSV 705, SFCR 125, and, IS 18551 experienced lower shoot
fly deadhearts at 28 days after seedling emergence, produced more number of productive tillers. The insects fed on these genotypes
also exhibited longer larval period (10.1–11.0 days compared to 9.3 days on Swarna), lower larval survival and adult emergence
(54.7–67.8 and 46.7–52.2% compared to 73.3 and 60.6% on Swarna, respectively), and lower growth and adult emergence indices
as compared to the susceptible check, Swarna. Physico-chemical traits such as leaf glossiness, trichome density, and plumule
and leaf sheath pigmentation were found to be associated with resistance, and chlorophyll content, leaf surface wetness, seedling
vigor, and waxy bloom with susceptibility to shoot fly and explained 88.5% of the total variation in deadhearts. Step-wise
regression indicated that 90.4% of the total variation in deadhearts was due to leaf glossiness and trichome density. The
direct and indirect effects, correlation coefficients, multiple and step-wise regression analysis suggested that deadhearts,
plants with eggs, leaf glossiness, trichomes on the abaxial surface of the leaf, and leaf sheath pigmentation can be used
as marker traits to select for resistance to shoot fly, A. soccata in sorghum. 相似文献
27.
M.?K.?Dhillon H.?C.?SharmaEmail author B.?V.?S.?Reddy Ram?Singh J.?S.?Naresh Zhu?Kai 《Euphytica》2005,144(3):275-283
Summary The shoot fly, Atherigona soccata is an important pest of sorghum, and host plant resistance is one of the most effective components for managing this pest.
Most of the hybrids grown in India based on milo cytoplasm (A1 cytoplasm) are highly susceptible to shoot fly. Therefore, the present studies were undertaken to evaluate different male-sterile
cytoplasms (CMS) for their relative susceptibility to sorghum shoot fly. Oviposition and deadheart formation were significantly
lower on the maintainer lines as compared to the corresponding male-sterile lines. Among the cytoplasms tested, A4M cytoplasm showed antixenosis for oviposition and suffered lower deadheart formation than the other cytoplasms tested. The
A4G1 and A4M cytoplasms suffered lower deadhearts in tillers than the other cytoplasms. Recovery following shoot fly damage in A4M, A3, and A2 cytoplasms was better than in the other cytoplasms tested. The larval and pupal periods were longer and male and female pupal
weights lower in A4M and A4VzM CMS backgrounds compared to the other CMS systems. Fecundity and antibiosis indices on CMS lines were lower than on the
B-lines. The A4M cytoplasm was found to be relatively resistant to sorghum shoot fly, and can be exploited for developing shoot fly-resistant
hybrids for sustainable crop production in future. 相似文献
28.
Hessian fly [Mayetiola destructor (Say)] is one of the major insect pests of wheat (Triticum aestivum L.) worldwide. Hessian fly resistance gene H9 was previously reported to condition resistance to Hessian fly biotype L that is prevalent in many wheat‐growing areas of eastern USA and an RAPD marker, OPO051000, linked to H9 in wheat was developed using wheat near‐isogenic lines (NILs). However, marker‐assisted selection (MAS) with RAPD markers is not always feasible. One of the objectives in this study was to convert an RAPD marker linked to the gene H9 into a sequence characterized amplified region (SCAR) marker to facilitate MAS and to map H9 in the wheat genome. The RAPD fragment from OPO051000 was cloned, sequenced, and converted into a SCAR marker SOPO05909, whose linkage relationship with H9 was subsequently confirmed in two F2 populations segregating for H9. Linkage analysis identified one sequence tagged site (STS) marker, STS‐Pm3, and the eight microsatellite markers Xbarc263, Xcfa2153, Xpsp2999, Xgwm136, Xgdm33, Xcnl76, Xcnl117 and Xwmc24 near the H9 locus on the distal region of the short arm of chromosome 1A, contrary to the previously reported location of H9 on chromosome 5A. Locus Xbarc263 was 1.2 cM distal to H9, which itself was 1.7 cM proximal to loci Xcfa2153, Xpsp2999 and Xgwm136. The loci Xgwm136, Xcfa2153 and SOPO05909 were shown to be specific to H9 and not diagnostic to several other Hessian fly resistance genes, and therefore should be useful for pyramiding H9 with other Hessian fly resistance genes in a single genotype. 相似文献
29.
Pigeonpea [Cajanus cajan (L.) Millsp.] is an important legume crop in South Asia, East and southern Africa, and the Caribbean. Pod fly (Melanagromyza obtusa Malloch) and pod wasp (Tanaostigmodes cajaninae La Salle) are important constraints to increase the production and productivity of pigeonpea under subsistence farming conditions. Host plant-resistance can be used as an important component for the management of these pests, and therefore, we evaluated 28 accessions of wild relatives of pigeonpea for resistance to these pests. There were significant inter- and intra-species differences in the relative susceptibility to pod fly and pod wasp damage. Accessions belonging to Cajanus scarabaeoides (L.) Thouars, C. sericeus (Benth. ex Bak.) van der Maesen, Rhynchosia bracteata Benth. ex Bak., C. acutifolius (F.v. Muell.) van der Maesen, C. lineatus (W. & A.) van der Maesen, and C. albicans (W. & A.) van der Maesen showed resistance to pod fly damage, while those from C. platycarpus (Benth.) van der Maesen, C. cajanifolius (Haines) van der Maesen and R. aurea DC. were susceptible. For the pod wasp, some of the accessions from C. scarabaeoides, C. albicans, Flemingia stricta Roxb., and R. bracteata (Roxb.) Wight showed a resistant reaction, while ICPW 83 belonging to C. scarabaeoides showed a susceptible reaction. ICPW 141, ICPW 278, and ICPW 280 (C. scarabaeoides), ICPW 214 (R. bracteata), ICPW 14 (C. albicans), and ICPW 202 (F. stricta) showed resistance to both pod fly and pod wasp damage. There was considerable variation in accessions belonging to different species for their susceptibility to pod fly and pod wasp, which can be exploited to breed for resistance to these pests. There was a negative association between pod wasp and pod borer damage, and therefore, it is important to keep track of the relative susceptibility of pigeonpea genotypes to pod wasp, while breeding for resistance to pod borers. 相似文献
30.
GIS技术与实蝇监测 总被引:3,自引:1,他引:3
实蝇监测体系的完善和技术的提高是我国植物检疫应对WTO挑战的一项重要任务。地理信息系统是一类现代信息技术 ,可以用于有害生物的监测工作。在综述GIS发展及其在植保应用的基础上 ,初步分析了实蝇监测的发展及现存问题 ,并就应用Web -GIS技术建立实蝇监测快速反应网络进行了探讨 相似文献