天津沿海都市型农业发展战略构想

本文对天津沿海都市型农业的内涵进行了定义,明确了未来5-15年战略定位,按照不同农产品对环境的要求,优化农业布局,提出发展良种农业、绿色生态农业、设施农业、加工农业、海洋农业、口岸农业、休闲观光农业的战略方向。通过实施科教兴农战略、城乡一体化战略、结构调整战略、农产品安全战略、循环协调战略,实现把天津农业建设成知识、技术、资本密集型的沿海都市型农业的战略目标。     

低耦合度3T1R并联操作手设计与运动学分析

基于方位特征(POC)方程的并联机构拓扑结构设计理论和机构结构降耦原理,设计了一种低耦合度能实现三平移一转动(3T1R)的SCRAR并联操作手机构。首先,阐述了该机构的组成,计算了该机构的耦合度k=1;然后,根据该机构的几何特点和运动约束,通过建立输入参数与动平台输出位姿参数间的约束方程,运用运动学序单开链法原理求解了位置正解的数值解,导出了其位置反解的解析解,用实例验证了位置正、反解的准确性;最后,基于位置反解得到了机构位置工作空间的形状与大小及Z向各截面形状,并基于Jacobian矩阵对机构奇异位形进行了分析。结果表明:该机构比H_4、I4结构简单,在一组相同等效尺寸参数下其工作空间大、转动能力强。     

Behavioral responses of potato tuber moth (Phthorimaea operculella) to tobacco plant volatiles

Potato tuber moth(PTM) Phthorimaea operculella, also known as tobacco splitworm, is an important pest of tobacco plants. The knowledge on the interaction of tobacco plant volatiles and PTM behavior is limited. To clarify the effect of tobacco plant volatiles on the orientation and oviposition behaviors of PTM and to identify potential compounds for PTM control, tobacco plant volatiles were collected by headspace collection method, and volatile compounds were identified by gas chromatography-mass spectrometry. Thirteen electrophysiological active compounds were screened by employing coupled gas chromatography-electroantennogram detection and from which nine available compounds were further verified by electroantennogram recording. cis-3-Hexen-1-ol showed significant attractant effect on the orientation behaviors of both male and female moths. Nonanal and decanal could only attract females, while octanal exhibited repellent effect on males. Oviposition selection experiment indicated that nonanal, decanal, decane and methyl hexadecanoate could stimulate the gravid females to lay more eggs, while octanal and 2,6-bis(1,1-dimethylenthyl)-4-methyl phenol inhibited their oviposition. Our study added more compounds to the list that could serve as potential PTM deterrents or attractants.     

Two farnesyl pyrophosphate synthases,GhFPS1–2, in Gossypium hirsutum are involved in the biosynthesis of farnesol to attract parasitoid wasps

Sesquiterpenoids play an import role in the direct or indirect defense of plants. Farnesyl pyrophosphate synthases(FPSs) catalyze the biosynthesis of farnesyl pyrophosphate, which is a key precursor of farnesol and(E)-β-farnesene. In the current study, two FPS genes in Gossypium hirsutum, GhFPS1 and GhFPS2, were heterologously cloned and functionally characterized in a greenhouse setting. The open reading frames for full-length GhFPS1 and GhFPS2 were each 1 029 nucleotides, and encoded two proteins of 342 amino acids with molecular weights of 39.4 kDa. The deduced amino acid sequences of GhFPS1–2 showed high identity to FPSs of other plants. Quantitative real-time PCR analysis revealed that GhFPS1 and GhFPS2 were highly expressed in G. hirsutum leaves, and were upregulated in methyl jasmonate(MeJA)-, methyl salicylate(MeSA)-and aphid infestation-treated cotton plants. The recombinant proteins of either GhFPS1 or GhFPS2 plus calf intestinal alkaline phosphatase could convert geranyl diphosphate(GPP) or isopentenyl diphosphate(IPP) to one major product, farnesol. Moreover, in electrophysiological response and Y-tube olfactometer assays, farnesol showed obvious attractiveness to female Aphidius gifuensis, which is an important parasitic wasp of aphids. Our findings suggest that two GhFPSs are involved in farnesol biosynthesis and they play a crucial role in indirect defense of cotton against aphid infestation.     

基于GIS的油菜播种控制系统设计与试验

针对江苏稻油轮作模式下由于水稻土壤湿黏导致地轮打滑而造成的漏播等问题,设计一套电控排种系统,对现有机械式油菜复式播种机进行自动化改造。播种作业时,该系统可根据计算机加载的播种作业信息、地图数据和实时获取的GPS位置信息确定当前播种参数,并发送到主控制器,经处理后,运用比例积分微分控制算法结合目标穴距和播种机前进速度,使用直流电机控制排种轴的旋转速度,实现油菜精准播种。试验结果表明,该系统控制电机转速的变异系数最大值为4.85%,台架试验中穴距变异系数的最大值为15.28%,较传统播种精度明显提高,且系统工作响应及时。     

基于转动惯量的采后甘蓝自动定向方法研究

针对采后甘蓝人工连续定向效率低、劳动强度大等问题,以“中甘15号”甘蓝为研究对象,提出了一种基于转动惯量的采后甘蓝自动定向方法。首先,建立了采后甘蓝的简化几何模型,对3个惯量主轴的转动惯量及其定向运动稳定性进行了理论分析;其次,建立了定向仿真模型,基于ADAMS软件分析了26种初始姿态的采后甘蓝在定向过程中的位移差值和采后甘蓝中心轴与辊轮轴线的夹角随时间的变化规律;最后,搭建自动定向试验平台,以辊轮直径、轴向间隙、径向间隙和角速度为试验因素,以采后甘蓝中心轴与辊轮轴线的夹角和定向成功率为试验指标,进行了单因素和正交试验。理论分析和仿真结果表明,采后甘蓝在定向运动过程中,逐渐趋向绕转动惯量最小且唯一的中心轴转动,且该运动状态动态稳定,即实现了采后甘蓝的自动定向。试验结果表明,试验因素对采后甘蓝中心轴与辊轮轴线的夹角影响的显著性主次顺序为辊轮直径、角速度、轴向间隙、径向间隙,试验因素对定向成功率影响的显著性主次顺序为角速度、辊轮直径、轴向间隙、径向间隙;最优参数组合为辊轮直径80mm、轴向间隙80mm、径向间隙70mm、角速度6rad/s。在最优参数组合下进行了验证试验,结果表明,采后甘蓝中心轴与辊轮轴线的夹角平均值为（6.72±1.23）°,定向所需时间为6.8s,定向成功率为96%,满足采后甘蓝自动定向及后续高通量处理的需求。     

关于加快发展河南农业生产性服务业的思考

阐述了河南省农业生产性服务业面临的发展机遇,指出了加快发展农业生产性服务业的总体要求,提出了加快发展农业生产性服务业的重点任务,以期促进河南省适度规模经营、推进农业供给侧结构性改革。     

“生态环境生产力论”对我国林业建设的价值引领

习近平总书记提出:“保护生态环境就是保护生产力,改善生态环境就是发展生产力”。以此为核心思想的“生态环境生产力论”,传承了马克思实践唯物主义的基本观点,蕴含了人与自然、社会和谐的价值诉求,张扬和凸显了“人创造环境,同时环境也创造人”的精神实质,体现了中国政府对生态环境也是一种生产力的积极认知,为我国当前林业建设提供了新的生产力标准,进一步为林业建设树立起价值维度,即从“发展绿色”走向“绿色发展”的生态之路。     

银中杨短轮伐期纸浆林定向培育技术研究

通过对银中杨进行苗龄型选择、造林密度、混交造林、营养元素测定和施肥等试验,对营造银中杨纸浆林的各环节的技术进行了定量和定性研究,确定了提高银中杨生长量和木材质量的技术措施。结果表明:银中杨纸浆林定向培育宜采用2根2干、3根2干壮苗,采用株行距2 m×4 m、3 m×4 m栽植,8~12 a轮伐。造林后的前3 a林粮间作。施肥的林龄是4~6 a,最佳施肥时间是7月上旬;最佳施肥配比为N∶P∶K=1∶0.84∶0.87。采用与胡枝子、沙棘混交造林,能促进银中杨的生长,减少病虫害的发生,生物量及光能利用率较纯林高15%左右。为半干旱地区营造纸浆林提供了配套技术措施。     

市场导向下傣族竹编工艺的创新路径

市场经济的发展使少数民族地区人们的生活水平得到了很大改善，但同时也迫使当地的传统工艺逐渐走向没落。文章以傣族竹编工艺为例，从传统工艺传承与现代技术融合、产品种类扩展与设计品质提升、产业模式探索与商业平台建设3个方面探讨了市场导向下少数民族传统工艺的创新路径。