Problems of control of insecticide-resistant Plutella xylostella

In the different regions of SE Asia, resistance problems in the diamondback moth (DBM), Plutella xylostella, are comparable, and depend on the type of insecticide used to control this pest. Resistance is especially high to insecticides metabolised by mfos (multifunctional oxidases), but since the detoxification of each such insecticide depends on different mfo(s), there is little cross-resistance between insecticides. Thus, carbaryl, carbofuran and the synthetic pyrethroids, all detoxified by mfos, show little cross-resistance. Resistance to cartap and some organophosphorus insecticides is much lower, and is often unstable. Those compounds are therefore essential in the rational control of DBM. The cross-resistance relationships within the traditional insecticides have mostly been worked out. It is thus possible to use alternate spraying schedules with insecticides conferring minimum cross-resistance potential. Alternating insecticides is better than using mixtures, because DBM can develop multiple resistance through treatment with mixtures. DBM has now developed resistance to the newly-introduced IGRs and other experimental control agents. Possible resistance to these as well as to future DBM control agents has been examined, and their resistance-inducing ability and cross-resistance characteristics examined. Experience in monitoring the spectrum together with the strength of resistance of field populations of DBM suggest that control can only be achieved by wellplanned rational chemical control programs.     

气候因素对禾谷缢管蚜发生程度的影响及预测

小麦禾谷缢管蚜Rhopalosiphum padi(L.)是本省小麦主要害虫,其发生程度受诸多因素的影响。作者通过整理1979—1987年田间系统调查资料,应用通径分析方法,对影响小麦禾谷缢管蚜发生程度的气候因子进行了研究。试验选取3月中旬均温     

福建省葡萄病毒病的调查和研究

１９９０～１９９２年作者对福建省葡萄产区进行了抽样调查，发现该省约３１％的果园有葡萄扇叶病（ＧＦＬＶ）和葡萄卷叶病（ＧＬＲＶ）。在调查的１１３００株葡萄中（６０２亩），ＧＦＬＤ株发病率为１３．２７％，造成葡萄减产２７．２％；ＧＬＲＶ株发病率为７．３％，减产２１．５％。病株表现为不同程度的种性退化，生长赢弱、停滞，果实品质下降，果粒成熟不齐。     

连作晚稻三化螟为害损失与防治指标研究

三化螟幼虫在晚梗稻分蘖、圆秆、孕穗、破口期均能侵入,所形成的为害株数、为害类型和幼虫存活率与生育期有密切关系,为害丛、株增长呈S型曲线。分蘖期、孕穗—破口期引起丛、株为害率和损失率与卵块密度显著相关,每个卵块损失稻谷分别为59.11±2.99g、74.58±3.31g。考种结果表明,产量损失的主要原因是有效穗减少。在现有生产条件下,三化螟经济允许卵块密度为:分蘖期130—150块/666.7m~2,孕穗—破口期100—120块/666.7m~2;防治指标:分蘖期100—110块/666.7m~2,为害团50—60个/666.7m~2,丛为害率2.0％—3.0％,株为害率1.0％—1.5％。     

鄂尔多斯西部地区土地荒漠化（退化）及其防治研究──以公卡汗苏木为例

本文分析了鄂尔多斯西部地区荒漠化的现状及发展过程，划分了轻度、中度、重度和严重荒漠化阶段，并分出极易、较易、较难三种潜在荒漠化等级，分别测算了面积，做出了图表。说明了风蚀与水蚀过程的特征。阐述了自然因素与人为因素在土地荒漠化过程中的交互作用。提出了退耕还牧封沙育草、实行防风蚀耕作、发展灌溉农业、合理轮牧、保护植被等防治荒漠化的有效措施。     

Effect of bone marrow stem cell transplantation on mdx mice at different ages

AIM: To study the effect of bone marrow stem cell transplantation on mdx mice at different ages. METHODS: The bone marrow stem cells of C57BL/6 mice (4-to-weeks age) were cultured in vitro for 3 days, then injected intravenously into the 6-week and 8-week aged mdx, which were preconditioned with 7 Gy γ ray. 12 weeks after being transplanted, the mdx mice were studied for the dystrophin protein expression on the skeletal muscle membrane. RESULTS: Three months after transplanted with bone marrow stem cells, about 16% and 7% muscles cells in 6-week and 8-week mdx mice expressed dystrophin protein， respectively. CONCLUSION: 12 weeks after transplantation with bone marrow stem cells of homologous series mice, different amounts of dystrophin protein expressed on the membrane of skeletal muscle cells were observed in different aged mdx mice. Bone marrow stem cell transplantation show more benefic effect for younger mdx mice.     

人-猪链球菌病的防治

2005年6月下旬以来。四川省资阳市及周边地区相继发生了人急性发病．病人出现高热、恶心、呕吐、伴有头痛等全身中毒症状，重者出现中毒性休克、脑膜炎为主要临床表现的病例．到2005年7月26日12时，累计发病117例，死亡24例，治愈出院5例。本次疫病的特点是病人发病急，死亡快，死亡率高。     

阿拉善板滩井盆地地下水及水化学特征研究

本文依据作者在板滩井盆地从事的水文地质调查，钻探、水质分析和地下水动态资料，并利用卫片、航片解释，对该盆地及所属沙漠人工绿洲的地下水形成机制，水资源平衡，水质分布规律等进行了探讨。     

Molecular breeding for virus resistant potato plants

To engineer resistance against potato virus X (PVX), the viral coat protein (CP) gene has been introduced into two potato cultivars. Stable expression of the gene in transgenic clones throughout the growing season has been obtained and resulted in considerably increased virus resistance. With varying frequencies depending on the original cultivar used, true-to-type PVX resistant transgenic clones have been obtained. Since deviant light sprout characteristics were invariably associated with aberrations in plant phenotype, they can be used in procedures to early screen for deviations. Furthermore, it has been possible to unequivocally discriminate between the original untransformed and independent transgenic cultivars. Although no relation has been found between the presence, if any, of the CP of potato virus Y (PVY) or potato leafroll virus (PLRV) in CP gene transgenic potato, appreciable levels of resistance to these viruses has been obtained. This suggests that the mechanism by which a viral CP gene in the potato genome evokes resistance, differs amongst various viruses.     

烟草气候斑病的发生规律及防治

１９９０－１９９４年研究结果表明，低温是诱发气候斑病的主要因素，不同品种抗性差异显著，氮钾比失调，偏施碳铵地发病严重，当大面积种植感病品种，寄主处于感病阶段，遇气温突然下降和多雨时，最易流行。在防治上，采取以农业防治为主、化学辅的有效措施。