近几十年来，保护性农业（conservation agriculture，CA）因其有利于农业可持续性发展而获得广泛推广，但其对田间生物多样性和作物生产力的综合影响尚不清楚。本研究通过调查传统耕作（conventional tillage，CT），免耕（no tillage，NT）和少耕（reduced tillage，RT）三种耕作方式下稻田生物多样性和病、虫、草害等指标发现，降低耕作强度能显著降低稻田虫害、病害和杂草的发生，同时增加田间捕食性天敌数量，进而提高水稻产量。连续两年的调查结果显示，在CT模式下稻田主要害虫如稻飞虱和福寿螺发生量分别为74.78和9.91 m^-2，而在RT模式分别为14.69和5.16 m^-2，发生量显著降低，并且在RT模式下病害发生率和杂草密度也均有明显下降。同时，实施RT的稻田水稻产量（7477.01 kg ha^-1）相比于CT（6489.19 kg ha^-1）增加15.22%。此外，在CT模式下稻田害虫捕食性天敌的平均密度为11.22 m^-2，而RT和NT模式下分别为19.73和20.48，虫口数显著增加，同时丰富度也显著增加，说明CA对促进农业生态系统生物多样性有重要作用。综上所述，实施RT有利于水稻病虫草害防治，提高水稻产量和农业生态系统可持续性。

哺乳动物子宫内膜的发育是一个涉及众多的调节因素的复杂过程。环状RNA （circRNAs）是一种自然存在的内源性非编码RNA家族的重要成员之一，有研究报道circRNAs在多种生理过程中发挥着重要的调控作用。目的：本研究旨在分析奶山羊发情周期非妊娠子宫内膜组织中circRNA的表达谱。方法：采用链特异性去核糖体转录组测序技术对发情第5天和发情第15天奶山羊的非妊娠子宫内膜组织样进行circRNAs表达谱分析，筛选两个时期差异表达的circRNAs并利用RT-qPCR进行验证；然后利用生物信息学分析两个时期差异表达circRNAs的宿主基因，进而进行GO 和KEGG分析；最后利用Targetscan 7.0和miRanda网站分析circRNAs和miRNAs的靶向结合关系。结果：奶山羊发情第5天和发情第15天的非妊娠子宫内膜组织中共有2331个差异表达的circRNAs（P<0.05），RT-qPCR检测的10个circRNAs变化趋势与测序结果一致；其中circRNA1460的宿主基因Nipped-B 样蛋白（Nipped-B-like，NIPBL）和circRNA8694的宿主基因钙反应性转录因子（calcium responsive transcription factor，CARF）降低其circRNAs的转录形式的水平（P<0.05）参与子宫内膜的发育；差异表达circRNAs的宿主基因GO和KEGG分析结果显示注释到紧密连接（Tight junctions）条目上和鸟苷三磷酸酶（GTPases）通路上的circRNAs参与了奶山羊子发情周期中非妊娠子宫内膜的发育过程；另外，本研究中得到的circRNAs与公共数据库中的436个山羊miRNAs有靶向结合位点。结论：奶山羊发情第5天和发情第15天的非妊娠子宫内膜组织中存在差异的circRNAs，生物信息学分析表明一些circRNAs参与奶山羊发情周期非妊娠子宫内膜的发育过程；本研究构建了奶山羊发情周期非妊娠子宫内膜circRNAs文库，丰富了奶山羊的转录组信息，有助于我们研究奶山羊子宫内膜发育过程中的分子调控机制，为进一步提高奶山羊的胚胎着床的成功率和繁殖率提供理论依据。创新点：本研究选择发情第5天和发情第15天奶山羊的非妊娠子宫内膜组织进行circRNAs表达谱分析；采用核糖体去除和链特异性文库构建方案进行RNA-seq测序，保留了完整的circRNAs序列，对样本中几乎全部的circRNAs序列进行鉴定和分析。

Blumeria graminis f. sp. tritici, the pathogen that causes wheat powdery mildew, is one of the most important diseases affecting wheat production in China, and the oversummering is the key stage of wheat powdery mildew epidemic.  The more oversummering regionalization of wheat powdery mildew has played an important role in disease prediction, prevention and control.  In this study, we analyzed the correlation between oversummering data of wheat powdery mildew and the meteorological factors over the past years, and determined that temperature was the key meteorological factor influencing oversummering of wheat powdery mildew.  The average temperature at which wheat powdery mildew growth was terminated (26.2°C) was used as the threshold temperature to regionalize the oversummering range of wheat powdery mildew.  This regionalization was done using the GIS ordinary kriging method combined with the Digital Elevation model (DEM) of China.  The results showed that annual probability of oversummering region based on Model 26.2 were consistent with the actual survey of the more summer wheat powdery mildew.  Wheat powdery mildew oversummering regions in China mainly cover mountainous or high-altitude areas, and these regions form a narrow north-south oversummering zone.  Oversummering regions of wheat powdery mildew is mainly concentrated in the high-altitude wheat growing areas, including northern and southern Yunnan, northwestern Guizhou, northern and southern Sichuan, northern and southern Chongqing, eastern and southern Gansu, southeastern Ningxia, northern and southern Shaanxi, central Shanxi, western Hubei, western Henan, northern and western Hebei, western Liaoning, eastern Tibet, eastern Qinghai, western Xinjiang and other regions of China.

Insect pheromone-binding proteins (PBPs) play important roles in transporting hydrophobic pheromone components across the sensillum lymph to the surface of olfactory receptors (ORs). However, the PBPs of the oriental fruit moth, Grapholita molesta, an important destructive pest of stone fruits worldwide, are not well characterized. In this study, two new putative PBP genes, GmolPBP2 and GmolPBP3, were identified from G. molesta antennae. The deduced amino-acid sequences of these two putative PBP genes are characteristic of the odorant binding protein family, containing six conserved cysteine residues. The genomic DNA sequence of each gene contained two introns. However, the lengths and positions of the introns differed. RT-PCR analyses revealed that the two GmolPBP genes are only expressed in the antennae of female and male moths. Quantitative real-time PCR indicated that the transcription levels of GmolPBP2 are far greater than those of GmolPBP3 in both female and male antennae. GmolPBP3 showed higher transcription levels in female antennae than in male antennae, while GmolPBP2 showed similar transcription levels in both female and male antennae. The transcript levels of both genes were significantly different in premating and post-coitum individuals, implying that mating affects the process of sex pheromone reception. To better understand the functions, two GmolPBPs were expressed in Escherichia coli, and the ligand binding assays were conducted. Results showed that GmolPBP2 has strong binding affinities to two sex pheromone components, E8-12:Ac and Z8-12:Ac, as well as weaker binding affinities to Z8-12:OH and 12:OH. GmolPBP2 also bound some ordinary odor molecules. However, the affinity of GmolPBP3 to both sex pheromones and ordinary odor molecules was very weak. These results show that GmolPBP2 plays the main role in pheromone discrimination and recognition in the oriental fruit moth.

This study was carried out to investigate the transfection effect of exogenous gene into plant protoplast cell mediated by polyethylenimine (PEI) nanovector, based on PEI gene delivery system in the field of medical science. PEI/DNA complexes were prepared by using PEI polymer to bind the plant expression plasmid, pCMl205-GFPn. The ability of PEI combining and protecting DNA was investigated by agarose gel electrophoresis retardation assay. The surface characteristics of PEI/DNA complexes were observed with transmission electron microscope. The transfection efficiency of Arabidopsis thaliana protoplasts mediated by PEI/DNA complexes at different N/P ratios was analyzed based on observation of transient expression of green fluorescent protein with confocal laser scanning microscope. PEI could bind and condense DNA, and form stable 100-200 nm PEI/DNA complexes when the proportion of PEl and DNA is in the range of 5:1-1:4. Transfection efficiency of PEI/DNA complexes increased with N/P ratios in range of N/P<5 and reached the highest at N/P=5, and began to decrease beyond N/P>5 as higher toxicity to cells. The transfection efficiency of PEI/DNA complexes at N/P=5 was higher than PEG. This study confirmed that PEI nanovector could effectively mediate foreign gene entering into A. thaliana protoplast cell to obtain transient expression, which may be developed as a hopeful and novel transgenic method combined with plant protoplast regeneration.

In order to provide technological support for risk estimation of pesticide residues taken from vegetables, the residues of pesticide in vegetables in Jinan City, China, were investigated. Moreover, the variability of pesticide residues in vegetables was explored, and the variability factor was calculated. The level of pesticide residue was studied by statistical method. The variability factor was calculated using the Harrell-Davis method in accordance with principles recommended by the JMPR. In addition, the procedure of evaluation was validated according to the principles laid down by the JMPR (Joint Meeting on Pesticide Residues). The detection rate of pesticide residues in all marketplace samples was less than 20% in Jinan City. The unqualified rate of vegetables was low (0.6%). The chlorothalonil was found as the pesticide with the highest rate of detection. The vegetables with the highest rate of pesticide residues detected were leafy vegetables. The relationship between variability factor and mean value of concentrations of contaminations was expressed by the formula, v=4.9×Cmean. The pesticide residues in vegetables from Jinan City is low. The evaluated variability factor is larger than that the value recommended by the JMPR, however, less than the default value used for acute intake assessment of pesticide residues in UK in most cases.