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11.
从植物组成抗性与诱导抗性两个方面,回顾了植物抗瘿螨的研究进展。其中,组成抗性研究已较为透彻,本文从遗传、组织结构与形态、代谢产物3个方面进行综述;而诱导抗性从诱导抗性方式论述,主要有瘿螨取食、化学物质诱导和机械损伤3个方面。诱导抗性还有待进一步的深入研究,仍有很大的研究空间。 相似文献
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14.
福建省毛竹害螨暴发成因与防治管理对策 总被引:7,自引:0,他引:7
通过对福州市毛竹害螨危害与毛竹产值损失关系的调查 ,推算出福建省毛竹害螨危害造成的经济损失。在全省范围内对毛竹害螨暴发成灾原因进行调查、分析的基础上 ,制定了综合防治措施 ,并针对害螨防治工作中存在的问题 ,提出防治管理对策 相似文献
15.
O. M. B. De Ponti 《Euphytica》1978,27(2):435-439
Summary For several generations subpopulations of the twospotted spider mite were reared on cucumber varieties previously selected as partially resistant. Subsequently resistance tests were carried out in the laboratory and the glasshouse with mites from these subpopulations and concurrently with mites from a basic population reared on a susceptible cucumber line. In these tests neither acceptance nor net reproduction or damage index on the partially resistant varieties depended on the kind of mite populations used as inoculum. Therefore it is concluded that the resistance is genuine. The stability of the resistance is discussed. 相似文献
16.
O. M. B. de Ponti 《Euphytica》1977,26(3):641-654
Summary The relationship between the twospotted spider mite and cucumber has been studied on plants and on leaf disks of a number of varieties with different levels of resistance. Existing laboratory tests are critically discussed and it appears that they are only reliable if many factors are taken into account. A new, more efficient laboratory test for resistance, measuring acceptance and reproduction is described. 相似文献
17.
Elizabeth Keep 《Euphytica》1985,34(2):509-519
Summary In black currant (Ribes nigrum) backcross progenies segregating for resistance to the gall mite, Cecidophyopsis ribis
Westw. (gene Ce from Ribes grossularia L.), and to American gooseberry mildew, Sphaerotheca mors-uvae (Schw.) Berk. (gene Sph
3from R. glutinosum), significant differences in season of leafing out occurred between the resistant and susceptible classes. The data are consistent with the hypothesis that two additive genes, Lf
1and Lf
2, controlled season of leafing out and that Ce and Sph
3 were linked with Lf
1. 相似文献
18.
Summary The inheritance of resistance to the twospotted spider mite and of bitterness in cucumber has been studied in three sets of P1, P2, F1, F2, B11 and B12 of crosses between three bitter, resistant lines and one non-bitter, susceptible line. Resistance to the twospotted spider mite as measured by acceptance and oviposition appeared to be determined by several to many genes, which are inherited mainly in an additive fashion. Bitterness is basically governed by the gene Bi, which, contrary to earlier reports, is inherited in an intermediary way, while the expression of Bi is influenced by additively inherited intensifier genes. Whereas Bi and the bitterness intensifier genes are not related to the resistance factors acceptance and oviposition, they are related to resistance or tolerance as measured by the damage index. This relation is explained by linkage rather than by identity of the genes concerned. Changes in the test methods and breeding consequences are discussed. 相似文献
19.
朱砂叶螨抗药性研究 总被引:19,自引:0,他引:19
1986~1987年测定了河南省12个产棉县、市棉田朱砂叶螨对当前主要杀螨剂的抗性水平和多种农药对抗性叶螨的毒力水平.结果显示,朱砂叶螨已对三氯杀螨醇和氧化乐果产生抗性,各棉区基本处于抗性上升阶段.其中对三氯杀螨醇的抗性相对倍数较高,LC_(50)和LC_(95)值分别是相对敏感品系的1.72~8.26和3.47~17.67倍.从抗性品系对23种农药的感受性看出,朱砂叶螨已形成对硫磷高抗品系,抗性倍数达466.8倍;对磷胺、久效磷等也表现较高的抗性,但对甲氰菊酯、PP321、克螨特等尚未产生明显抗性,三环锡、Nissorun、毒死蜱、来福灵等有较好的杀若螨作用,对卵的抑制作用以Nissorun为最强,其次为浏阳霉素和杀虫脒. 相似文献
20.
Hongjie Li Robert L. Conner Qin Chen Robert J. Graf André Laroche F. Ahmad A. D. Kuzyk 《Genetic Resources and Crop Evolution》2005,51(8):827-835
Wheat streak mosaic virus (WSMV), vectored by the wheat curl mite (WCM),Aceria tosichella Keifer, is one of the most destructive viral diseases of wheat found in many wheat producing areas of the world. Host resistance is the most effective method for controlling this disease and its vector. Symptomatological analysis and enzyme-linked immunosorbent assay (ELISA) were used to characterize WSMV-resistance in wheat-alien partial amphiploid lines and their derivatives. The results showed that most of partial amphiploids derived fromThinopyrum ponticum andTh. intermedium were free of systemic symptoms with very low ELISA readings that were similar to that of the non-inoculated Chinese Spring control. While the partial amphiploid lines 693 and PWM706 were identified as new genetic resources of resistance to WSMV. The present study demonstrated that both symptomatological and ELISA methods efficiently assessed WSMV-resistance in the wheat-alien hybrids and systemic symptom incidence and ELISA absorbance readings were highly correlated (r
2 = 0.8658–0.9323) over time following inoculation. The ELISA results also indicated that the virus did not buildup in the plant tissues of these virus-resistant partial amphiploids. Similar results were observed in chromosome translocation and substitution lines that have the geneWsm1 conferring WSMV resistance. However, the lines containing the geneWsm1 and all the partial amphiploid lines, except Agrotana, were susceptible to the WCM. One line derived from a cross of wheat and Agrotana, was effective in controlling the spread of WSMV and was highly resistant to the WCM. Another line and an accession ofTriticum dicoccoides (Koern.) Schweinf. were highly susceptible to WSMV and WCM. Early disease development was delayed in a new hard red winter cultivar McClintock. The partial WSMV-resistance of McClintock was demonstrated by initially low ELISA readings, and a lower percentage of infected plants than other WSMV-susceptible wheat. The use of the identified promising sources of resistance to WSMV and the WCM in wheat breeding is discussed.LRC Contribution No. 387-01061. 相似文献