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M. Bonierbale R. Plaisted S. Tanksley 《European journal of plant pathology / European Foundation for Plant Pathology》1992,98(Z2):211-214
Introgression of trichome-mediated insect resistance from the wild speciesSolanum berthaultii has become a major focus of the potato improvement program at Cornell University during the past twelve years. Several quantitative characters are involved in this resistance which is effective against a wide range of pest types. Correlative biochemical assays have been developed to assay specific components of the resistance, and the effects of the resistance on the target pests have been studied. Quantitative laboratory assays and specific measurements of insect behavior and biology have increased the precision of selection and enable the investigation of the genetic control of the resistance.We are currently using restriction fragment length polymorphisms (RFLPs) for genetic mapping of factors controlling the trichome traits fromS. berthaultii. Backcrosses to both the wild and the cultivated species parents have been evaluated for phenotypes contributing to the resistance mechanism, including trichome density, sucrose ester and polyphenol oxidase production by the trichomes, and the enzymatic browning reaction responsible for insect entrapment. Genetic maps are being developed for these progenies, using RFLP markers previously mapped in potato. Field and greenhouse trials under insect infestations are also being conducted with the mapping progeny. Our goal is to locate genes responsible for quantitative insect resistance by correlating RFLP variation at mapped loci with the trichome phenotypes and insect resistance. Genetic markers for these traits will be useful in transfer of the effective wild chromosomal segments into and among tetraploid potatoes, and for a better understanding of the resistance mechanism. 相似文献
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J A Angell R E Merideth J N Shively R L Sigler 《Journal of the American Veterinary Medical Association》1987,190(10):1319-1322
Thirty-five dogs with ocular lesions associated with coccidioidomycosis were examined. Serologic and/or histologic evaluation confirmed the diagnoses of coccidioidomycosis. The disease most frequently associated with signs referable to the anterior segment of the eye, such as iritis and granulomatous uveitis. Histologic evaluation of the eye revealed a primary posterior segment disease, such as chorioretinitis or retinal separation, with an extension into the anterior segment of the eye. 相似文献
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Rolando Cabello Philippe Monneveux Felipe De Mendiburu Merideth Bonierbale 《Euphytica》2013,193(2):147-156
Drought strongly influences potato (Solanum tuberosum) production and quality. Potato being a drought susceptible crop, the development of varieties with enhanced tolerance to water stress could highly improve productivity in drought prone areas. The objective of this study was to evaluate the ability of several yield based indices to be used in large scale screening for drought tolerance. The experiment included improved varieties, genetic stocks and landraces potatoes grown under drought and irrigated conditions. A group of accessions with high yield under both conditions was identified. Mean productivity (MP), geometric mean productivity (GMP), tolerance (TOL), drought tolerance index (DTI), drought susceptible index (DSI) and yield stability index (YSI) were calculated from tuber yield under drought and irrigated conditions. The relationships between these indices and yield were analyzed. The Fleiss’ Kappa concordance test was used to analyze the correspondence between accessions previously identified as highly productive under both drought and irrigated conditions and accessions with optimal values for the different indices. MP, GMP and DTI allowed identifying genotypes combining high yield potential and high yield under drought within the three subsets of genotypes. Conversely, DSI, YSI and TOL showed low and variable concordance values across subsets, suggesting that their efficiency in screening genotypes highly depends on the nature of the tested genetic material. 相似文献
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J A Angell J N Shively R E Merideth R E Reed K C Jamison 《Journal of the American Veterinary Medical Association》1985,187(2):167-169
Enucleation of the right eye was performed on a 12-year-old male Persian cat when therapy for uveitis failed. Histologic examination of the anterior and posterior chambers and the vitreous led to a diagnosis of endophthalmitis caused by Coccidioides immitis infection. The primary focus of infection was not determined. Latex particle agglutination, agar gel immunodiffusion, and complement fixation gave negative results for Coccidioides immitis antibody. 相似文献
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The effect of IV mannitol (1.5 gm/kg) or oral glycerol (1.4 and 2.0 gm/kg) on intraocular pressure (IOP) and serum osmolality (SOSM) was investigated in 24 normal dogs. Mean IOPs were significantly decreased from baseline values from 0.5 through 5.5 hours following mannitol administration with a mean maximum depression of 8.7 +/- 1.8 mm Hg whereas mean SOSM was significantly increased from baseline values. Mean IOPs were significantly decreased from baseline values from 1.0 through 10 hours following oral administration of 1.4 gm/kg glycerol with a mean maximal depression of 5.4 +/- 2.7 mm Hg. Mean SOSM increased initially followed by a significant decrease. The change in IOP following mannitol administration showed less variation (smaller standard deviations) than glycerol (1.4 gm/kg). Five of the 6 dogs that received the 2.0 gm/kg glycerol vomited; the mean IOP and SOSM values were not significantly altered from baseline values in these dogs. Four of 5 dogs given cooled (10C) 2.0 gm/kg glycerol vomited. The incidence of vomiting appeared to be dose related. Both mannitol and glycerol (1.4 gm/kg) are effective for decreasing IOP in normal dogs. 相似文献
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I. Lefèvre J. Ziebel C. Guignard J.‐F. Hausman R. O. Gutiérrez Rosales M. Bonierbale L. Hoffmann R. Schafleitner D. Evers 《Journal of Agronomy and Crop Science》2012,198(3):196-206
Mineral micro‐ and macronutrients in tubers of 21 Andean potato cultivars were investigated in a field trial under control and drought conditions. Mineral concentrations in potato tubers were highly variable between genotypes; some were significantly and positively correlated with each other, the most noteworthy associations being Na–Ca, Mn–Mg and Zn–Fe, in both control and drought‐stressed plants. Overall, increasing yields are related to decreased concentrations of some nutrients, albeit some higher‐yielding cultivars also displayed important concentrations of nutrients in their tubers. The most striking result was the increase in the concentration of the majority of the analysed cations in a large number of cultivars in response to water depletion; some of them, such as K, may be related to water homeostasis and/or to sucrose loading and unloading in phloem sap. Tuber mineral concentrations were not related to drought tolerance in terms of tuber productivity. Interestingly, yield loss under drought was not correlated with yield potential under control conditions. Identification of cultivars such as 703264 and 701106 able to maintain good yield stability in association with high mineral contents under water deprivation is of particular interest, especially in view of the importance of potato as a staple crop and the expansion of its cultivation to non‐optimal cultivation areas in the context of changing climatic conditions. 相似文献
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Rolando Cabello Philippe Monneveux Merideth Bonierbale M. Awais Khan 《American Journal of Potato Research》2014,91(5):492-499
Drought is one of the major abiotic factors that affect potato production in the tropics and sub-tropics. Molecular plant breeding offers promising opportunities for developing drought tolerant cultivars, but genetic gains to be achieved through breeding depends strongly on the genetic variance and heritability of traits used in the selection process. In the present study, genetic variance and heritability of tuber yield and its components were estimated in the native potato cultivar group Andigenum, expected to include promising drought tolerant progenitors. Twenty-seven full sib families obtained from crossing 18 parents arranged in 3 mating sets were grown under irrigated and terminal drought conditions. Heritability for tuber yield, estimated from female to male variance components was 0.68 and 0.41, respectively, in the irrigated treatment, and only 0.18 and 0.06 under drought conditions. Tuber number was highly significantly correlated to tuber yield but the heritability of this trait (estimated both from female to male variance) was lower than yield heritability and its non-additive genetic variance was higher than its additive genetic variance, particularly when estimated from the female variance component. Heritability of average weight per tuber estimated for male variance component was very high under both irrigated and drought conditions. Its additive genetic variance was much higher than its non-additive genetic variance. However, average weight per tuber correlated to tuber yield within parents but not within families. These results indicate that selection for increased tuber yield under drought conditions in the Andigenum cultivar group may be slow due to its low heritability and high value of non-additive genetic variance. They also suggest that yield components may not be useful as indirect selection criterion for yield, because of their low heritability and/or poor association with yield. The identification of drought tolerance related traits with high heritability and closely associated to tuber yield under drought is consequently required to improve adaptation of potato to drought-prone conditions and efficient utilization of Andigenum potatoes for this purpose. 相似文献