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901.
针对目前肉鸽养殖业中存在的品种、营养、饲料、乳鸽销售等问题 ,提出了六点发展对策 ,期望对肉鸽业的发展有所帮助。 相似文献
902.
不同食料植物对舞毒蛾生长发育的影响 总被引:4,自引:0,他引:4
该文在以北京主要乔灌木树种为食料、室内饲养舞毒蛾的条件下 ,分析了不同食料植物对舞毒蛾生长发育的影响 .1龄幼虫成活的试验表明 :受试各树种间存在显著差异 ,舞毒蛾 1龄幼虫在柿、杏、黄栌、毛泡桐、火炬树等树种饲养下死亡率较低 ,在核桃楸、国槐、刺槐、臭椿等树种饲养条件下死亡率较高 .4龄幼虫对食物的利用和转化的试验表明 :舞毒蛾对柿树、黄栌、杏树、加杨的营养效率较高 ,对华山松、国槐、刺槐、白蜡和抗虫杨的营养效率较低 . 相似文献
903.
904.
The commercial expansion of roasted pepper as a high market value product have made that the period of time in which canning industries process the fresh pepper fruits needs to be extended. Fresh sweet pepper (Capsicum annuum L.) destined for industry grown in different sites was cold stored in order to analyse the effect of different sites and storage conditions on the quality of the product at harvest and during storage. Storage during 10 days at 8 °C was the best storage condition to improve quality of pepper destined for industry, because colour was improved, weight loss (1–1.6%) was lower than maximum permissible and decay incidence was only between 0% and 2.3%. Harvest should be delayed until pepper reaches the red state in order to increase the quality of the fruit. However, these results suggest that pepper growers should assure a high content of Ca (>0.6 g kg−1) in the soil to avoid a high incidence of decay during storage when a late harvest is needed to guarantee the enhancement of colour in pepper fruit destined for industry. These storage conditions are in accordance with those found to improve the sensory quality of roasted pepper. 相似文献
905.
根据GenBank上已发表的其他真菌α–微管蛋白基因序列中的保守区域设计简并引物,扩增出银耳α–微管蛋白基因的cDNA部分序列。分别利用SEFA-PCR方法和RACE技术,克隆了银耳α–微管蛋白基因的DNA和cDNA全长序列。银耳α–微管蛋白基因DNA全长1 962 bp,含有9个内含子,cDNA全长1 347 bp,编码448个氨基酸。生物信息学分析结果表明:银耳α–微管蛋白基因的cDNA序列与新型隐球酵母有80%相似性,编码的蛋白质属于Tubulin_FtsZ超家族中的α–微管蛋白亚家族,氨基酸序列中存在保守的GTP结合区域GGGTGSG,系统发育树显示银耳与新型隐球酵母距离最近。 相似文献
906.
夏季填闲作物及秸秆还田对日光温室黄瓜连作土壤养分和微生物的影响 总被引:4,自引:2,他引:2
选用已进行4 a温室夏季种植甜玉米、菜豆及其秸秆还田试验的温室黄瓜连作土壤,于2009年继续进行相同的处理,研究了温室夏季填闲作物及秸杆还田对黄瓜连作土壤养分和微生物代谢功能的影响。结果表明,种植甜玉米秸秆还田处理能减小土壤容重,改善土壤通透性。夏季填闲及秸秆还田处理对土壤养分和微生物的影响在秋冬茬表现较明显,能增加土壤中有效磷含量,种植菜豆处理(秸秆还田和不还田)能增加土壤有效钾含量。填闲作物及秸秆还田处理还能提高土壤微生物代谢活性,改变土壤微生物对单一碳源的利用能力。 相似文献
907.
Several treatments were applied in order to delay postharvest degreening in broccoli florets and investigate their effects on genes associated with chlorophyll catabolism. Degradation of chlorophylls is the most evident visual manifestation of broccoli postharvest deterioration, occurring rapidly due to the immature stage in which the material is harvested. Treatments such as storage in modified atmosphere, exposure to hot air, UV-C and white lamps were employed in the current work to induce a delay in degreening and chlorophyll degradation. Expression of genes possibly related to chlorophyll catabolism was analyzed in these samples and discussed. Chlorophyllases, the enzymes traditionally believed to remove the phytol side chain from chlorophyll appear to have a gene expression that was not regulated by postharvest treatments. Pheophytinase, a recently discovered new enzyme in this metabolic pathway, correlated chlorophyll loss accurately in heat, UV-C and white-light treatments, but not in modified atmospheres. Results presented in this work indicate that postharvest treatments that delay chlorophyll degradation have a higher effect on the expression of pheophytinase rather than on chlorophyllase genes. 相似文献
908.
Thirty-nine grapevine cultivars widely grown in Portugal, especially in Vinhos Verdes and Douro regions, and two well known international cultivars as standards, were genotyped at 12 microsatellite loci. The number of alleles per locus ranged from 6 to 12, and the number of allelic combinations per locus from 13 to 26. The total number of unique genotypes in the 12 analysed loci was 120, having most of the cultivars (38 out of 41) at least one unique genotype in any of the loci. The microsatellite profiles were adequate to discriminate 41 cultivars. The level of observed heterozygosity at each locus varied from 70.7% to 95.1%. VVMD28 has been revealed as one of the most informative markers. Several synonymies between Spanish and Portuguese cultivars were confirmed, and some homonymies are discussed. The genetic profiles of all 41 cultivars were searched for possible parent-offspring groups. The data obtained revealed the possible descendence of Touriga Franca from Touriga Nacional and Marufo. 相似文献
909.
Heat treatments have been applied in fruit postharvest technology for insect disinfestations, decay control, ripening delay and modification of fruit responses to other stresses. Heat treatment affects several aspects of fruit ripening, such as ethylene production and cell wall degradation probably through changes in gene expression and protein synthesis. In this paper, strawberries (Fragaria × ananassa Duch., cv Camarosa) at 50–75% red stage of ripening were heat-treated at 45 °C during 3 h in an air oven and then stored at 20 °C for 0, 4, 18, 24 and 48 h. Fruit firmness was determined and the expression of a set of expansin genes (FaEXP1, FaEXP2, FaEXP4, FaEXP5 and FaEXP6) was analyzed. The firmness of treated fruit was higher than that of control fruit 24 h after treatment, though the differences disappeared after 48 h at 20 °C. The analysis by northern-blot indicated that heat treatments affected differently the expression of expansin genes. The expression of FaEXP1, FaEXP2 and FaEXP6 was lower in treated fruit during the following 24 h post-treatment. The lower expression of these expansin genes could contribute to delay softening after heat treatment. 相似文献
910.
AIM: To investigate the role of voltage-dependent anion channel (VDAC) in H9c2 cardiomyocytes subjected to anoxia/reoxygenation (A/R).METHODS: The shRNAs targeting VDAC1 mRNA were inserted into pSUPER plasmid.H9c2 cells were randomly divided into 5 groups as follows: control group, A/R group, anoxia preconditioning (APC) group, pSUPER-VDAC1-A/R group and pSUPER-A/R group. The expression of VDAC1 was detected by Western blotting. Cellular injury was evaluated by measuring the cell viability and the release of lactate dehydrogenase (LDH) and creatine phosphokinase (CPK). The mitochondria membrane potential was determined by flow cytometry.RESULTS: VDAC1 expression was up-regulated in A/R group and was inhibited in APC group. Similarly, down-regulation of VDAC1 expression by shRNA protected H9c2 cells from A/R injury. Moreover, we found that, with silencing VDAC1 expression, mitochondrial membrane potential was well preserved in H9c2 cells subjected to A/R.CONCLUSION: Down-regulation of VDAC1 protects H9c2 cells against A/R injury and its possible mechanism appears to be related to the regulation of mitochondial permeability transition pore opening. 相似文献