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181.
Sweet cherry (Prunus avium) and sour cherry (Prunus cerasus) trees from orchards in the Kootenay and Okanagan Valleys of British Columbia, Canada were assayed for the presence of little cherry disease by three different methods: Northern blot analysis of double-stranded RNA, woody indexing for fruit symptoms on sweet cherry cv. Lambert, and woody indexing for foliar symptoms on cv. Canindex 1. Results of the three methods were in agreement for 85% of the samples. Of the 78 orchard trees tested, double-stranded RNA isolated from 48 trees hybridised with a radiolabeled cloned probe specific for little cherry disease. When the 48 trees were tested by woody indexing, buds from 41 trees induced fruit symptoms on cv. Lambert, but only 32 yielded foliar symptoms on cv. Canindex 1 under the conditions of the experiment. Of the 30 orchard trees that did not yield a positive response to the Northern blot analysis, 26 samples were negative on cv. Lambert and 26 were negative on cv. Canindex 1. Northern blot analysis of the 78 cv. Lambert indicator trees revealed that there was an absolute correlation between the presence of little cherry disease-associated double-stranded RNA and the development of typical little cherry disease symptoms on the indicator trees. Reliability of woody indexing of orchard samples was impaired by poor transmission of the disease from the inoculating bud to the indicator tree. Woody indexing with cv. Canindex 1 was particularly prone to a large number of apparently erroneous negative results. Of the three protocols used, diagnosis of little cherry disease by Northern blot analysis was found to be the most reliable and offered a greatly accelerated means of diagnosis. 相似文献
182.
A. R. Granger 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,93(3):426-430
Eight polymorphic isozyme loci, 6PGD, G6PD, MDH, PGM, SKDH, FDP, GOT and IDH, in sweet cherry where found to be in one linkage group, with a ninth isozyme locus, GPI, being in another linkage group on a different chromosome. Isozymes were also linked to the incompatibility S locus and this explained the disturbed segregation ratios observed in the first generation from controlled hybridisations between different sweet cherry cultivars. Analysis revealed close linkage between the isozyme and S loci. The results supported a pre-existing theory that the S gene in cherry consists of three linked segments each coding for a different function. Progeny derived from selfing of Stella, the self-fertile cherry cultivar, also showed disturbed segregation ratios and an absence of homozygotes for the isozyme loci assayed. This demonstrated that codominant inheritance of the S alleles had not been effected by the self-fertile mutation. 相似文献
183.
Abstract. The European cherry fruit fly (Rhagoletis cerasi L.; Diptera, Tephritidae) marks cherries (Prunus avium L.) after oviposition with a host marking pheromone (HMP). The marking trail prevents additional oviposition by the same or other females into the same fruit. On the ventral side of the tarsi of both sexes, contact-chemoreceptor sensilla were identified which contain a receptor cell selectively sensitive to HMP. The HMP receptors of males were slightly more sensitive than those of females, suggesting that the more general term ‘host-marking pheromone’ is more appropriate than the previously used ‘oviposition deterring pheromone (ODP)’. The four structural isomers of the HMP, N(15R, S(β-glucopyranosyl)-oxy-8RS-hydroxypalmitoyl)-taurine, and various derivatives were synthesized and tested in an electrophysiological bioassay. Both the 8R,15R and the 8S,15RS isomers of the HMP were equally active with a threshold of about 2 times 10-10M, and were shown to be present in the female faeces in similar proportions. The two 15S HMP isomers were about 13 times less active. Testing synthetic derivatives of the HMP molecule revealed that the presence of the four moieties of the molecule are important for the activity: taurine, palmitic acid, C(8) hydroxyl group, and glucose (C(15)). The chain length of the fatty acid, the hydroxyl group at C(8) and the position of glucose at C(15) also influenced the activity. Only minor loss of activity (factor 2) relative to the natural molecule was observed when the methyl group in the C(15) position was removed. The removal of the β-glycosidically linked glucose (replaced by a hydroxyl group) resulted in about a 4-fold loss of activity. The cation of the HMP molecule seemed to have no effect on its activity, whereas both low and high pH reduced it significantly. Based on these results, field experiments have been initiated to control oviposition by cherry fruit flies on cherries applying the 15-desmethyl-HMP derivative. 相似文献
184.
The entire senescence period, including ripening, is characterized in cherry tomato ( Lycopersicon esculentum Mill. var. cerasiforme Alef.) by two successive changes in overall polar lipid content. The rise in respiration of the fruit in the climacteric phase is accompanied by a large increase in lipids, notably phospholipids, such as phosphatidylcholine and phosphatidic acid. This suggests the coexistence of anabolic and catabolic processes in this first period. At the degreening stage of the fruit, decreased levels of monogalactosyldiacylglycerol and the disappearance of trigalactosyldiacylglycerol may indicate some degradation of the chloroplast compartment. Following a respiratory upsurge, a sudden breakdown of total lipids occurs concomitantly with maximal ethylene production. This breakdown is essentially caused by a parallel decrease in the amounts of phosphatidylcholine, phosphatidylethanolamine, phosphatidic acid and also phosphatidylglycerol. However, in the cherry tomato, lipid peroxidation, evaluated by alteration of fatty acid distribution, seems insufficient to account for the ethylene peak. 相似文献
185.
Quinyl esters of hydroxycinnamic acids usually occur in greater abundance than their corresponding glucose esters in tomato fruits. During fruit growth and ripening, the predominant derivatives of hydroxycinnamic acids were found to be chlorogenic acid (76%) and the glucosides (84%) respectively. The variations in the ratio of Benedict-reactive (chlorogenic acid) and non-reactive compounds (mainly caffeic acid glucoside) are discussed in relation to their possible role in the regulation of fruit growth and maturation. 相似文献
186.
187.
以1年生甜樱桃砧木‘吉塞拉6号’和‘考特’幼苗为材料,采用盆栽试验,研究不同浓度NaCl(0、50、100、150 mmol·L^(-1))处理对其主要渗透调节物质、抗氧化酶活性、光合特性以及叶绿素荧光参数的影响,探究甜樱桃砧木对盐胁迫响应的生理机制。结果表明:(1)NaCl处理促进了甜樱桃砧木叶片中可溶性糖、可溶性蛋白和脯氨酸等渗透调节物质的积累。(2)随着NaCl处理浓度的升高,甜樱桃砧木叶片中SOD活性呈现升高趋势,而POD活性表现出先升高后降低趋势。(3)随着NaCl处理浓度的升高,甜樱桃砧木叶片的净光合速率(P_(n))、气孔导度(G_(s))逐渐降低,而胞间CO_(2)浓度(C i)逐渐升高,非气孔限制为甜樱桃砧木叶片P_(n)下降的主要因素。(4)NaCl处理抑制了甜樱桃砧木叶片的最大光化学效率(F_(v)/F_(m))、光化学淬灭系数(q P)和电子传递效率(ETR),增加了非光化学淬灭系数(NPQ)。研究发现,盐胁迫破坏了甜樱桃砧木的光合机构,抑制了电子传递速率和光化学量子效率,降低了对光能的利用率,导致光合速率降低;甜樱桃砧木在盐胁迫条件下主要通过增加渗透调节物质含量和提高抗氧化酶活性来缓解渗透胁迫并降低氧化损伤,从而提高对盐胁迫的适应能力;‘吉塞拉6号’在盐胁迫条件下表现出更强的适应能力,其耐盐性更强;甜樱桃砧木在高于100 mmol·L^(-1)NaCl处理时表现出明显受害症状。 相似文献
188.
K W Lee H C Suhk K S Pai H J Shin S Y Jung E T Han J Y Chai 《The Korean journal of parasitology》2001,39(4):319-321
Diphyllobothrium latum infection in human is not common in Korea and only thirty seven cases have been reported since 1921. We report two cases of fish tapeworm infection after ingestion of raw cherry salmon (Oncorhynchus masou) caught in the domestic river. Among four family members who ate together raw salmon flesh six months ago, just two, mother and daughter, were infected. It is our expectation that the salmon associated tapeworm infections would be enlisted as one of the major parasitic problems with the growing consumption of salmon in Korea. 相似文献
189.