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101.
The root lesion nematode Pratylenchus penetrans parasitizes a wide range of economically important crops, including potato (Solanum tuberosum). Damage by P. penetrans impacts not only the potato yield but can also reduce the tuber quality. Detailed information on tuber infection by P. penetrans is scarce for most cultivars and molecular detection of nematodes from infected tubers is needed. The objective of this study was to assess tuber symptomatology due to P. penetrans infection in 10 potato cultivars and to provide an accurate molecular methodology for nematode detection using tuber peels. Sprouts of certified potato seed from cultivars Agata, Agria, Camel, Désirée, Dirosso, Kennebec, Laura, Picasso, Royata, and Stemster were planted in 2 L pots, and soil was inoculated with 4 P. penetrans/g of soil. Sixty days after inoculation, tubers were harvested, inspected for lesions, and the number of nematodes/g of potato peel assessed. Observations of tubers with symptoms showed the presence of P. penetrans in superficial layers of peels around the lenticels and injured necrotic tissue. Different nematode stages were detected in tubers of all inoculated cultivars, varying from 4 to 46 nematodes/g of potato peel. Species-specific primers showed suitable sensitivity and reproducibility for the detection of P. penetrans in tuber potato peel samples. The molecular detection of P. penetrans directly from tuber peels can facilitate routine nematode inspections of potato seed tubers or cull potatoes for nematode detection, and prevent further dissemination of this species.  相似文献   
102.
通过分析高校图书馆社会化服务的可行性、优势及现状,认为地方高校图书馆开展社会化服务不仅必要,而且完全可行。根据我国高校图书馆社会化服务存在的法律政策缺失、思想认识误区、服务数量较少、服务方式被动、服务限制多、效果差等突出问题,并结合地方实际情况有针对性地提出地方高校图书馆开展社会化服务应坚持的策略和具体途径。  相似文献   
103.
We examined arsenic (As) accumulation and speciation in the major cultivars currently grown in Japan, because differences in grain As levels among cultivars may influence dietary As exposure in Japanese people. Ten major cultivars (Oryza sativa L.) were grown under flooded conditions in a paddy field with a background level of As (low-As soil) or in pots filled with soil containing a high level of As (high-As soil). In the low-As soil, the total grain As ranged from 0.11 to 0.17?mg?kg?1, with a mean concentration of 0.14?mg?kg?1, and inorganic As was the major species in all cultivars. There were few genotypic differences in the levels of either total As or inorganic As in the grain. In the high-As soil, total grain As increased to a mean level of 2.4?mg?kg?1 in the 10 cultivars, with markedly increased levels of dimethylarsinic acid. The genotypic variations among cultivars in the levels of both total As and dimethylarsinic acid were statistically significant. However, the genotypic variability of inorganic As levels was quite small, and these levels remained low (at about 0.2?mg?kg?1) even when total As levels increased markedly. These results suggest that differences in grain As levels among Japanese cultivars may not influence dietary As exposure, because there is little genotypic difference in the accumulation of inorganic As, which is considered more toxic than organic As to humans. We discuss the possible mechanism of As accumulation in Japanese paddy rice, in the context of the accumulation of As species in the developing grain and in other plant tissues.  相似文献   
104.
路爽  廖国进  侯亚红 《安徽农业科学》2009,37(35):17662-17664
对沈阳地区‘08.7.5’局地暴雨天气与‘08.7.15’区域暴雨天气过程进行了对比分析,发现副高与西风槽相迎合是沈阳地区典型暴雨天气形势之一。  相似文献   
105.
Longnan City in Gansu Province is the largest base of olive production in China. In the olive orchard locating in Wudu District of Longnan City, thirty trees were sampled each of three cultivars, ‘Leccino’, ‘Chenggu32’, ‘Ezhi8’, with monoconical and vase training system. After planted with density of 5×6 m in 1992, each sample tree was investigated to determine the yield fresh fruit in five different years. The results of survey and analysis showed that there were significant differences of fruit yield among 5 years and 3 cultivars. Different canopy shapes yielded some effect on fruit setting rate and yield of different cultivars in different years. During first fruiting period in the fourth/sixth year after planting, fruit setting rate and yield of ‘Leccino’ with monocone were more 6.7% and 0.15 kg than those with vase and those of ‘Ezhi8’ and ‘Chenggu32’ with vase were more 20%, 10% and 0.18 kg, 0.09 kg than those with monocone. With the increase of tree age, fruit set and yield of ‘Leccino’ and ‘Ezhi8’ with vase was more than those of monocone. In 2011, average yields per tree of ‘Leccino’ and ‘Ezhi8’ with vase were more 13.35 kg and 6.85 kg than those with monocone. And the highest yield per tree of ‘Leccino’ with vase was 75 kg, more 16 kg than that of monocone. Fruit trees with yield over 35 kg of ‘Leccino’ and 25 kg of ‘Ezhi8’ with vase accounted for 80% and 46.7%, more 40% and 30.01% than those of monocone. It was concluded that vase training system would produce higher yield of ‘Leccino’ and ‘Ezhi8’ and its effect and advantages were gradually prominent with increase age. As for ‘Chenggu32’, monocone got a slightly higher yield than that of vase and in 2011 fruit trees with yield over 15 kg accounted for 25%, more 8.34% than vase. The difference between two training system of this cultivar was not obvious.  相似文献   
106.
天水地区小麦品种抗条锈性变异动态监测研究   总被引:3,自引:0,他引:3  
通过系统调查和试验查明,天水地区种植的重要品种77-69和成良5号、6号已丧失抗条锈性,引致这些品种丧失抗锈性的原因主要是条中29号小种及其相近致病类型的出现和发展,山区低温为引致变异的重要诱因。提出成良5号、6号应停止种植,77-69高产可在川区控制使用,并提出了抗性比较稳定的品种。  相似文献   
107.
铁观音和黄棪是乌龙茶茶树育种的骨干亲本,以这2份品种及其为亲本选育出的新种质及不同地域种质的铁观音茶树为研究材料,采用ISSR分子标记技术,利用筛选出的9个多态性较好、扩增条带较清晰的ISSR引物,分别对24份茶树品种(系)进行扩增,分析其遗传多样性和亲缘关系。结果表明:9个ISSR引物共扩增出73条稳定的谱带,其中47条具有多态性,多态性比率为64.4%,平均每个引物扩增出5.2条谱带;遗传相似性分析显示24份供试种质的遗传相似系数0.544~0.889,平均为0.727,表明供试种质的遗传基础较窄,亲缘关系较近。  相似文献   
108.
为给锥栗杂交育种和遗传作图的亲本选配提供参考,应用SSR分子标记技术,分析了福建省建瓯市17个锥栗主栽农家品种的遗传多样性。结果表明:不同农家品种遗传多样性丰富,利用筛选出的12对引物组合扩增的片段大小主要在50~2 000 bp之间,共扩增出180个位点,多态位点163个,占90.56%;17个锥栗主栽农家品种的遗传相似性系数在0.509 2~0822 1之间,乌壳长芒和牛角仔(晚熟)的相似性系数最大,中尖嘴与白露仔的相似性系数最小,且在相似性系数为0.60处,大尖嘴和中尖嘴单独聚为I类,在相似性系数为0.77处,第II类又被分为A~H共8个组;SSR引物组合Cs CAT33和Cm TCR4共同构建了17个锥栗主栽农家品种的DNA指纹图谱。  相似文献   
109.
N. Van  Stallen  V. Noten    V. Neefs  M. de  Proft 《Plant Breeding》2001,120(5):425-428
The phylogenetic relationship between different Cichorium intybus cultivars and cultivar groups was studied. A total of 127 random amplified polymorphic DNA markers have been used to distinguish between 51 Cichorium intybus cultivars belonging to three different cultivar groups. A principal component analysis was performed on the complete data set and a clear grouping of chicory cultivar groups was observed. The three chicory groups tested (root chicory, witloof and pain de sucre) were separated from one another in the principal component plots. The first two axes accounted for 43.9% of the total variation. Although the chicory used in traditional forcing in soil and the red chicory cultivars were related more to each other and to the chicory cultivars from the witloof group, they still formed separate groups in the principal component plot.  相似文献   
110.
Colic surgery is one of the most painful procedures carried out in horses. Common strategies to alleviate immediate postsurgical abdominal pain include the administration of potent systemic analgesics; however, these may cause unwanted adverse effects such as cardiovascular depression, ileus, and ataxia. The administration of local anesthetics at the incision site in form of an ultrasound-guided subcostal transversus abdominis plane (TAP) block may therefore be preferred to provide adequate analgesia without significant side effects. To date, no technique for a TAP block in horses undergoing median celiotomy has been described. The objective of the study was to develop a TAP block technique, which will lead to the desensitization of the ventrolateral abdominal wall and adjacent skin area of experimental Shetland Ponies using bupivacaine 0.125%. This is a prospective, blinded, self-controlled trial. A cadaver study was performed to determine the ideal injection points and the volume required to stain the nerves responsible for the sensation of the ventrolateral abdominal wall and skin in Shetland pony cadavers (i.e., T9–L 2). Subsequently, using the ideal injectate volume and the landmarks obtained in the first phase of the study, six Shetland ponies received a bilateral TAP injection, either with a local anesthetic solution (bupivacaine 0.125%) or with saline in a randomized, crossover, blinded fashion. Effectiveness was determined over a 4 hour postinjection time, by using a pinprick technique. Significant differences were found to the responses of the pinprick evaluation between the bupivacaine- and saline-treated sides after 30 minutes of TAP block injection. Reported “learned behavior” could have affected the results of the pinprick testing. The TAP block technique reported in this study using bupivacaine 0.125% appeared effective in desensitizing the lower abdomen of ponies for up to 2 hours. Further research is required to apply this technique in horses undergoing celiotomy. Potentially larger volumes and/or higher concentrations of bupivacaine may be necessary to provide longer duration of action of the block.  相似文献   
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