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21.
柳蝙蛾危害对水曲柳木材性质的影响 总被引:1,自引:0,他引:1
采集同一立地条件柳蝙蛾危害的幼龄水曲柳,将其木材分4组:健康株、危害1a化学防治后愈合株、柳蝙蛾危害1a未防治株、危害3a以上的水曲柳。对危害部位进行解剖学、物理学实验,结果表明:柳蝙蛾对水曲柳木材的密度、硬度、胞壁率、年轮宽、纤维长度几个指标均有不同程度的影响。化学防治后1a密度这一指标恢复正常水曲柳的密度;年轮宽在被害后第三年才能恢复;对硬度的影响在以后的3a仍十分明显,纤维长度同硬度影响相近。 相似文献
22.
正黑斑病是三七栽培生产中常见的一大病害,叶片受害产生近圆形或不规则水浸状病斑,常导致成株落叶、幼苗生长点及茎秆顶端腐烂枯死。其病原一般认为是链格孢属真菌人参链格Alternaria panax Whetzel~([1,2]),也有相关研究证明黑斑病病原为细链格孢Alternaria tenuis Nees~([3]),后定名为链格孢Alternaria alternata Keissl~([4])。本研究利用ITS序列和histone 3部分编码序列的PCR鉴定,结合形态学鉴定,分析三七主产区黑斑病菌的组成和分布情况及几种病原菌的致病力差异,以期为三七黑斑病防治提供理论依据。 相似文献
23.
东方百合鳞茎快速增长的组培体系研究 总被引:1,自引:0,他引:1
以东方百合栽培品种‘Sorbonne’和‘Siberia’的组培苗为试验材料,研究了蔗糖、6-BA、IAA、PP333及活性炭(AC)的添加浓度对组培苗小鳞茎增重和直径生长的影响;结果表明:80g/L蔗糖浓度有利于‘Sorbonne’和‘Siberia’组培苗小鳞茎增重;6-BA浓度为0.2mg/L、IAA浓度为0.5和1.0mg/L时‘Sorbonne’和‘Siberia’组培苗小鳞茎平均直径增加最大,分别为120.7%和138.0%;PP333浓度达3.2mg/L和1.6mg/L时,‘Sorbonne’和‘Siberia’的组培苗小鳞茎平均直径增加最大,分别达到505.7%和211.3%;AC浓度达到2.0g/L时‘Sorbonne’试管苗小鳞茎平均直径增加最大,浓度达到4.0g/L‘Siberia’组培苗小鳞茎平均直径增加最大,分别为194.7%和220.3%。 相似文献
24.
高校扩招后专业培养与社会需求的结构矛盾分析 总被引:2,自引:2,他引:0
以浙江省高校扩招政策的实施情况为例,分析高校扩招过程中的规律性问题;结合浙江省经济发展现象与趋势,重点分析高校学科专业扩展与就业岗位需求之间的结构性矛盾。 相似文献
25.
Rell L. Parker John Du Richard L. Shinn Adam G. Drury FangChi Hsu John L. Roberston Thomas E. Cecere Avril U. Arendse John H. Rossmeisl 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2022,36(2):694
BackgroundSeizures in the early postoperative period after intracranial surgery may affect outcome in dogs.ObjectivesTo determine the incidence of early postoperative seizures (EPS) in dogs with brain tumors, identify specific risk factors for EPS, and determine if EPS affects outcome.AnimalsEighty‐eight dogs that underwent 125 intracranial surgeries for diagnosis and treatment of rostrotentorial brain tumors.MethodsRetrospective cohort study. All patients with a diagnosis of rostrotentorial brain tumor from 2006 to 2020 were included. Early postoperative seizures were diagnosed by observation of seizure activity within 14 days of neurosurgery. Previously diagnosed structural epilepsy, perioperative anticonvulsant drug (ACD) use, magnetic resonance imaging (MRI), and tumor characteristics were evaluated. Outcome measures included neurologic and nonneurologic complications, duration of hospitalization, and survival to discharge.ResultsDogs with rostrotentorial brain tumors had EPS after 16/125 (12.8%) neurosurgical procedures (95% confidence interval [CI], 7%‐19%). Presence of previous structural epilepsy was not associated with EPS risk (P = 1). Perioperative ACD use also was not associated with EPS (P = .06). Dogs with EPS had longer hospitalization (P < .001), were more likely to have neurologic complications postsurgery (P = .01), and were less likely to survive to discharge (P = .01).Conclusions and Clinical ImportanceIt is difficult to predict which dogs are at risk of EPS because the presence of previous structural epilepsy and the use of perioperative ACDs was not associated with EPS. However, seizures in the early postoperative period are clinically important because affected dogs had prolonged hospitalization, more neurologic complications, and decreased short‐term survival. 相似文献
26.
为深化科技体制机制改革,贯彻落实创新驱动发展战略,积极推进科研院所治理体系和治理能力现代化建设,省级农业科研院所如何贯彻落实好中央和省里赋予科研单位的管理自主权,进一步完善以科研业绩和实际贡献为导向的激励分配机制,是当前科研院所深化改革的重要任务。文章以福建省农业科学院为例,阐述该院激励评价体系的建设现状,分析其激励制度存在的问题,从科研院所激励评价指标体系建设的原则和路径切入,构建了一套省级农业科研院所激励评价指标体系,为积极推进省级农业科研院所激励分配机制改革提供了一种制度设计,是科研院所治理体系和治理能力现代化建设理论与实践有机结合的积极探索。 相似文献
27.
Effect of LED light quality on the phototaxis and locomotion behaviour of Haliotis discus hannai
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Xiaolong Gao Mo Zhang Jimeng Zheng Xian Li Liang Chi Changbin Song Ying Liu 《Aquaculture Research》2016,47(11):3376-3389
Abalones were reared in a laboratory to determine the percentage response rate, response time, average crawling speed and the time taken to recover an upright posture under nine light‐emitting diode light quality treatments (red, orange, yellow, green, cyan, blue, purple, white and grey) and a dark environment. Animals were placed in the centre of an experimental device, and the tropism of each animal was continuously monitored by video. The highest percentage response rate (80% in dark adapted abalones, 60% in light adapted abalones) was observed in the dark environment, followed by red and orange light (27% and 30% in dark adapted abalones, respectively, 22% and 24% in light adapted abalones). Two induction materials (substrate and brown algae Laminaria japonica) were used to assess the effect of light quality on the tropism of abalones, with the highest percentage response rate (76% in the L. japonica treatment, 22% in the substrate treatment) also observed in the dark environment, followed by red and orange light (both 25% in the L. japonica treatment, and 26% and 32%, respectively, in the substrate treatment). The tropism order of the abalones under dark, red, orange and yellow light was as follows: dark > orange > red, yellow, but fewer abalones chose to stay in blue, green, cyan and purple light. The response time (about 700 s) in the dark environment was significantly longer than for the other light quality treatments. Compared with the average crawling speed in the other light quality treatments, abalones were relatively slower (about 3.8 mm s?1) in red and orange light, and the dark environment. The mean time required for the recovery of an upright posture in red light and the dark environment was longer than in the other light quality treatments, with the average recovery time reaching a maximum of 60 s in the dark environment. The results demonstrate the phototaxis and locomotion behaviour of abalones, as well as confirming the necessity of a dark, orange or red environment for their management and aquaculture. 相似文献
28.
Effects of Dietary Digestible Protein and Energy Levels on Growth Performance,Feed Utilization,and Body Composition of Juvenile Permit,Trachinotus falcatus (Linnaeus, 1758)
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Huy Quang Nguyen Thiet Chi Chu Thuy Thi Le Nguyen Ivar Lund 《Journal of the World Aquaculture Society》2018,49(5):943-952
A 9‐wk study was conducted to evaluate the effect of dietary protein and energy on growth performance of juvenile permit, Trachinotus falcatus, growing from approximately 30 to 150 g. Nine experimental diets were formulated to contain three levels of crude protein (400, 450, and 500 g/kg dry matter [DM]); and three levels of crude lipid (100, 200, and 300 g/kg DM) in a 3 × 3 factorial design. Growth rate and feed efficiency were significantly improved with increasing dietary protein levels from 400 to 500 g/kg and with dietary lipid levels from 100 to 200 g/kg. Fish body protein content was positively correlated with dietary ratio of digestible protein (DP) to digestible energy (DE) (P < 0.01, R2 = 0.83), while body lipid was negatively correlated with dietary DP/DE (R2 = 0.55, P < 0.05) but positively correlated with dietary DE levels (R2 = 0.66, P < 0.01). Results showed a protein‐sparing effect, as protein retention was significantly increased by increasing dietary lipid level. In conclusion, the diet containing DP of 392.7 g/kg and DE of 18.8 MJ/kg (DM), corresponding to a DP/DE of 20.9 g/MJ, is suggested as an optimal feed for growth and feed efficiency in juvenile permit. 相似文献
29.
30.
Eun Ju Cho Do Jin Lee Chi Do Wee Hong Lim Kim Yong Hwa Cheong Ju Sik Cho Bo Kyoon Sohn 《Scientia Horticulturae》2009,122(4):633-637
We aimed to investigate the effects of inoculating Panax ginseng C.A. Meyer seedlings with arbuscular mycorrhizal fungi (AMF) by examining the root colonization, plant nutrition uptake, growth characteristics, and soil aggregation of P. ginseng seedlings inoculated at the time of transplantation. At 16 weeks, the AMF spore density per 30 g of fresh mycorrhizosphere in seedlings inoculated with AMF (AMF+ seedlings) was 256.8 and that in seedlings not inoculated with AMF (AMF− seedlings) was 186.3, respectively. The colonization rate of AMF in the lateral roots of AMF+ seedlings was approximately 19% higher than that in the lateral roots of AMF− seedlings. The patterns of AMF colonization in ginseng roots were similar to those of the Paris-type mycorrhizal association. Plant growth characteristics, such as plant height, root length, leaf area, number of lateral roots, fresh weight of shoots and roots, and chlorophyll content, were significantly enhanced in AMF+ seedlings compared to AMF− seedlings. The macronutrient content (P, K, and Ca) and micronutrient content (Cu, Fe, and Zn) of both shoots and roots were also significantly higher in AMF+ seedlings compared to AMF− seedlings. Furthermore, glomalin content and soil aggregation were significantly enhanced in AMF inoculated areas. Our results indicate that AMF inoculation may enhance the growth of ginseng seedlings by improving the uptake of mineral nutrients and the soil structure in mycorrhizosphere. 相似文献