基于qPCR和LAMP技术的马铃薯晚疫病菌快速检测方法

马铃薯晚疫病菌（Phytophthora infestans）能侵染多种茄科植物,它引起的马铃薯晚疫病,是马铃薯生产中的第一大病害。为了开发能在田间快速检测马铃薯晚疫病病原的方法,利用P. infestans T30-4基因组测序数据的contig 1.18131,设计qPCR和LAMP引物,优化扩增条件后得到引物的特异性和灵敏度,最后通过检测田间收获薯块,比较形态学传统方法、qPCR及LAMP的差异。特异性检测结果发现,qPCR和LAMP仅在含有P. infestans DNA模板的体系有阳性扩增,在寄主和其他微生物DNA中均无扩增;在优化的条件下,qPCR和LAMP的检测下限可达1×10 ^-6ng/μL,在有寄主和其他微生物DNA存在的条件下,引物的灵敏度没有显著差异。利用两种快速方法对在大理、丽江及昆明3个地区田间收获薯块上检测发现,qPCR和LAMP方法得到的检出率差异极为不显著（P=0.420）,两种快速检测方法和形态学鉴定方法检出率差异极显著（P=0.009）。在大理、丽江及昆明3个地区的薯块中,两种分子检测方法检出率均比形态学方法高。其中,qPCR检测方法比形态学方法分别提高了12.00%、2.00%、8.70%;LAMP检测方法比形态学方法分别提高了11.30%、2.00%、8.70%。     

基于深度学习的病虫害智能化识别系统

我国农作物种植覆盖面广、分散度高,病虫害发生种类多、区域性发生规律复杂,传统的人工鉴定技术从效率、能力与精度方面均难以满足新形势下重大病虫测报要求。针对这一实践需求,以测报灯下害虫图像数据库(约18万张)、田间病虫害图像数据库(约32万张)为基础,构建了基于深度学习方法的病虫害种类特征自动学习、特征融合、识别和位置回归计算框架,并研发了移动式病虫害智能化感知设备和自动识别系统。通过近2年的精确度和实操运行效率检验,该系统在自然状态下对16种灯下常见害虫的识别率为66%～90%,对38种田间常见病虫害(症状)的识别率为50%～90%。随基础数据库的不断丰富、神经网络深层特征提取的不断完善,该系统有望进一步提高识别准确率,从而真正实现田间病虫害识别自动化、智能化和高效率。     

新型脱叶剂欣噻利在赣北棉花上的应用效果初报

为考察新型脱叶剂欣噻利在赣北的使用效果,以中棉所425为试验材料,进行脱叶剂处理试验。结果表明: 喷施欣噻利1800～2700 mL·hm^－2有较好的脱叶催熟效果,在此范围内其剂量越大,脱叶催熟的效果越好;喷施欣噻利对棉花铃重、铃壳质量、衣分以及纤维品质没有显著影响。     

基于PWM的远程控制新型变量喷雾系统设计

针对目前地面植保喷雾机械的局限性,开发了一种新型的变量喷雾系统。该系统在保持电动离心喷头压力和流量不变的前提下,采用离心雾化方式,雾化盘由三相无感无刷直流电机带动,利用ARM控制器输出频率固定占空比不同PWM信号作为无刷直流电机电子调速器的油门转速信号,改变雾化盘的转速,从而改变雾滴的粒径大小及覆盖率等参数。该系统采用了一个功率较大的无线收发模块SI4432,最大距离达到2km范围(这也是和其他远程喷雾系统相比根本的优势),用单片机和上位机远程实时地控制雾化盘的转速,同时在上位机和液晶屏幕上显示占空比。最后,利用设计的变量喷雾平台,在喷头压力为0.5MPa、流量为2L/min、雾化盘直径为5 8 mm的条件下,获得了离心雾化喷头在不同的占空比对应的雾滴中值直径和覆盖率大小,通过上位机就可以实现电动离心喷头转速的较大范围的调整,可以在不同喷雾环境下针对不同的农作物使用这套系统。     

新型具有力感知的柔性果蔬采摘机械手研究

研发了基于设施农业的果蔬采摘机械手,包括具有3个旋转关节自由度的采摘机械臂及具有力反馈功能的三指果蔬采摘末端执行器,并对其控制系统进行了开发。通过采摘模拟试验,验证了其作业性能、采摘效果。试验结果表明:采摘机械手各关节与控制系统配合良好,运行稳定;采摘末端执行器手指控制灵活,传感器响应灵敏,能够实现稳定抓取并不损伤果实,具有推广价值。     

水稻生产全程机械化技术经济效益分析

通过对水稻生产水田耕整、育插秧、植保、收获和谷物烘干等环节机械化生产的经济效益进行分析,同时对比传统人工种植的投入与产出的经济效益,得到了实施水稻生产全程机械化具有省工高效、节本增收、高产稳产、投入产出比高等优点,是解决水稻生产劳动力短缺、成本高、比较效益低的必由之路,是农业可持续发展的必然需求。      

重庆市丘陵山区绿肥机械化轻简生产实践

针对高标准农田建设宜机化地块整理整治后的土壤培肥熟化问题,及近年来因过度施用化肥而导致的土壤酸化、板结等问题,重庆市通过绿肥种植试验示范,结合土壤环境保护和机械化生产技术,创新探索出了绿肥机械化轻简生产技术。其主要体现为2次机械化作业（抛撒和深松整地）完成传统生产方式中的6个作业环节（灭茬、旋耕、开沟、播种、施肥和盖种）。绿肥机械化轻简生产可减少化肥施用量,节约生产成本,保持和提高耕地质量,保护和改善生态环境,保证和提高农产品的产量及品质,促进农业的可持续发展。      

Dyeing performance of the azo dyes containing trifluoromethyl group for polyester fabrics and its single crystal structure

The structures of disperse dyes and their intermolecular interactions have important impacts on dyeing and printing performances for polyester fabrics. The fluorine dyes show some unique molecular stability and photochemical properties. The dyeing property of the azo dye containing trifluoromethyl group for polyester fabrics, 4'-(N-acetoxyethyl-Nethyl)- amino-2-bromine-4-nitro-6-trifluoromethylazo- benzene (D1), was investigated and compared with the similar structure disperse dye. The results show that the high color yield and good exhaustion of the dyed PET fabrics could be obtained. The polyester fabrics dyed with D1 had excellent light fastness. Its single crystal was prepared and the supramolecular interactions were solved by X-ray diffraction. Dye D1 formed triclinic crystals in a trimeric packing mode. The C-F bond distances of CF3 are 1.2730 Å, 1.2240 Å and 1.2900 Å, respectively. The two benzene rings linked azo unit (-N=N-) are obviously twist. The dihedral angle of the two benzene rings is 50.23 o. There are six weak hydrogen bonds around trifluoromethyl group in the intramolecule and intermolecule. The excellent light stability of the dye should be attributed to its unique supramolecular structure.     

Agronomic traits of soybean cultivars released in different decades after grafting record‐yield cultivar as rootstock

Breeders have seldom considered the selection for root traits during the genetic improvement in soybean. It is hypothesized that grain yield would be increased by the root function improvement, especially for the current cultivars. The objective of this grafting experiment was to determine the effect of record‐yield cultivars L14 or Z35 as rootstocks on agronomic traits of cultivars released in different decades. A total of 11 cultivars, released in different decades, were used to graft onto L14 or Z35 rootstocks. The agronomic traits were measured in the pot‐culture experiments. Grafting cultivars released in different decades onto L14 or Z35 rootstocks resulted in higher yield, 100‐seed mass and apparent harvest index as compared with those of non‐grafted or self‐grafted plants. Grain yield gain of cultivars grafted onto record‐yield cultivar rootstocks was 0.40 g/plant/year from 1966 to 2006, which was larger than that of non‐grafts and self‐grafts (0.27 g/plant/year). The yield of current cultivars should increase more if their root functions were improved.