不同施肥量对安康烤烟新品种生长发育及经济性状的影响

为明确安康烟区烤烟新品种肥料适应性,以‘云烟97'、‘云烟99'、‘红花大金元,、‘中烟103,、‘云烟100'、‘NC297’、‘NC71’、‘兴烟1号’、‘K326(对照)’和‘云烟87’(对照)为试验材料,研究不同施肥水平对烤烟新品种(系)的农艺性状、植物学性状、抗病能力、原烟外观质量和经济性状的影响.结果表明,在农艺性状方面,施肥量的增加,各参试品种(系)株高、茎围和腰叶长都有不同程度的增加趋势,但随着施肥量的增加,增加趋势趋缓.在抗病性方面,‘云烟97’、‘云烟99’、‘云烟100’和‘NC297,综合抗病能力较强.在经济性状方面,产量和产值‘云烟97’、‘云烟100’、‘NC297’和‘云烟99,品种在中等施肥水平综合表现最好.     

基于ADAMS的采伐联合机臂系运动学仿真分析

对于多自由度机器人的运动学分析,一般采用D-H方法,但其计算复杂,准确度不高。采用先进的运动学分析软件ADAMS,对设计的采伐联合机臂系建模并进行运动学分析,研究采伐机在工作过程中整个臂系的运动状况,以及伐木头的运动轨迹和速度的变化情况,为研究采伐联合机臂系是否会发生干涉碰撞和样机的调试奠定理论基础。     

中南地区甜玉米丰产栽培技术

本文从土地选择、品种选择、怖种与育苗、田间管理、病虫害防治、适时收获等六个方面,总结了中南地区甜玉米的丰产栽培技术.     

Effect of high dietary carbohydrate on growth,serum physiological response,and hepatic heat shock cognate protein 70 expression of the top-mouth culter <Emphasis Type="Italic">Erythroculter ilishaeformis</Emphasis> Bleeker

To investigate the effects of different carbohydrate (CHO) levels in the diet of top-mouth culter Erythroculter ilishaeformis Bleeker, fish were randomly divided into five treatment groups. A control group was fed a diet with no CHO, and four treatment groups were fed with 14, 21, 27, and 34 % CHO, respectively, for 70 days. Serum cortisol level, glucose concentration, alanine aminotransferase activity, and malondialdehyde content of fish offered the diet containing 27 % CHO or 34 % CHO were significantly greater than those of fish offered the diet containing 14 % CHO or 21 % CHO. Serum lysozyme activity, total antioxidation capacity, and superoxide dismutase activity of fish offered the diet containing 27 % CHO or 34 % CHO also were significantly lower than those of fish offered the diet containing 14 % CHO. The relative levels of hepatic heat shock cognate protein 70 messenger RNA (mRNA) of fish offered the diet containing 27 % CHO after being deprived of food for 48 h or 34 % CHO at 48 h after feeding were significantly higher than those of fish offered the diet containing 21 % CHO or 14 % CHO. The results of this study suggest that ingestion of 27 or 34 % dietary CHO can impact the nonspecific immune ability of E. ilishaeformis and also cause metabolic stress.     

基于深度学习和图像处理的水果收获机器人抓取系统

首先,介绍了水果收获机器人抓取系统的总体架构;然后,利用深度学习对水果目标识别进行了研究,实现了一套基于卷积神经网络的目标检测算法;接着,利用图像处理技术实现了对目标物体定位的功能,可以引导水果收获机器人完成对目标水果的采摘.实验结果表明:水果收获机器人抓取系统对水果坐标的计算误差较小,且具备较强的水果识别和定位能力.     

国产轻型木结构用落叶松胶合板覆板生产技术与性能评价

近年来,随着我国木结构建筑的发展,为满足市场需求,大量进口了北美针叶材结构胶合板和OSB用作轻型木结构房屋覆板。虽然2010年我国胶合板产量已达7139.66万m~3,但大部分用于装饰及家具制造,很少量用作建筑结构材料。国内有关结构胶合板的产品开发和性能研究较少,同时也缺乏成熟和完善的木结构用胶合板制造工艺和技术参数。笔者探讨利用国产落叶松原料生产木结构用胶合板覆板的生产技术及     

Virulence traits of avian pathogenic (APEC) and fecal (AFEC) <Emphasis Type="Italic">E. coli</Emphasis> isolated from broiler chickens in Algeria

Avian pathogenic E. coli (APEC) is the etiologic agent of avian colibacillosis, the most common disease responsible for chicken morbidity in the world. Although multiple virulence-associated factors were identified, their prevalence in Algeria is still poorly known. In the present research, 92 avian pathogenic E. coli (APEC) isolates were recovered from broilers with clinical signs and lesions of colibacillosis. In addition, 32 E. coli isolates collected from feces of healthy birds (AFEC) were included for comparison. All isolates were investigated by PCR for the presence of a total of 11 virulence-associated genes described for avian pathogenic (iroN, ompT, hlyF, iss, iutA, and fimC) and diarrheagenic E. coli (eae, stx, elt/est, ipaH, and aggR). The sensitivity of 39 APEC isolates to 16 antibiotics was also determined using antimicrobial pretreated microplates. Here, we report that 98% of the examined isolates host at least one of the tested virulence factors. The most prevalent genes in APEC were iutA (90.6%), ompT (86.9%), and iss (85.8%); whereas, iutA (78.1%), fimC (78.1%), and iroN (68.7%) were the highest prevalent genes in AFEC. Our data showed that none of the AFEC isolates harbor any of the tested diarrheagenic genes. Moreover, only elt/est (5.4%), stx (2.1%), and ipaH (2.1%) genes were carried by APEC isolates. We further established that ceftazodime, ceftiofur, mequindox, amoxicillin/clavulanic acid, and meropenem were the most efficient antibiotics against the analyzed APEC isolates. Overall, our findings provide more insights about APEC and AFEC virulence potential in Algeria which could participate in the fight against colibacillosis.     

凡纳滨对虾不同生长阶段肠道可培养细菌耐药性研究

在凡纳滨对虾(Litopenaeus vannamei)养殖过程中多使用微生态制剂来调节水质,为避免破坏池塘菌群结构,很少使用抗生素.为了解凡纳滨对虾肠道细菌耐药性与不同生长阶段的关系,本研究选取江苏地区4种主要养殖模式凡纳滨对虾成虾和虾苗作为研究对象,利用K-B纸片法和qRT-PCR技术,研究对虾样本肠道可培养细菌对...     

Soil nitrogen balance and nitrogen utilization of winter wheat affected by straw management and nitrogen application in the Yangtze river basin of China

Straw incorporation is a useful management practice in sustainable agricultural systems to improve soil fertility and to reduce air pollution from straw burning. A three-year field experiment was conducted under two rice straw managements and four nitrogen (N) application rates in Rugao, China during 2010–2013, to examine whether straw management practices integrated with fertilizer N applications affect crop yield, N balance and N use efficiency in the wheat season of rice-wheat cropping systems. The results showed that straw incorporation had positive effects on plant N uptake and grain yield. This may be attributed to the greater soil water content and lower amount of seasonal rainfall. However, straw incorporation resulted in lower soil inorganic N and more N surplus at the early growth stage. Grain yield had a significant relation with wheat N uptake from sowing to jointing and from jointing to anthesis with straw incorporation. Therefore, our results suggest that in adjusting the ratio of basal and topdressing N fertilizer, it is important for the supply of optimum N to the crop and to maintain grain production with straw incorporation.     

Relationship between stomatal behavior and characteristics of photosynthesis and transpiration of Adenophora Iobophylla and A. potaninii at different altitudes

The photosynthesis and transpiration characteristics ofAdenophora Iobophylla and A. potaninii, as well as stomatal behavior such as stomatal size, stomatal density, stomatal open and stomatal conductivity were measured at different altitudes. The relationship between the photosynthesis and transpiration characteristics and the stomatal behavior was analysed by correlation coefficient and path coefficient analysis with altitude changes.The results showed that the influences of stomatal behavior were not evident on the photosynthesis and transpiration characteristics of A. Lobophylla, but evident on that of A. potaninii.