拟南芥和酿酒酵母来源的磷脂：甘油二酯酰基转移酶与底物的潜在结合位点分析

为了探究拟南芥和酿酒酵母来源的磷脂:甘油二酯酰基转移酶（PDAT）在油脂积累过程中与底物相互作用的机制，本研究利用蛋白三维结构模拟、分子对接等生物信息学手段对植物、真菌等来源的PDAT进行蛋白进化分析以及PDAT与特定底物的分子对接分析。通过模拟PDAT和磷脂分子的空间对接模型，预测出底物和蛋白空间互作的多个关键氨基酸位点。基于多种磷脂分子和AtPDAT的分子对接和氨基酸序列比对，AtPDAT氨基酸序列中的W153，E310，D313，V627可能对蛋白质和底物结合发挥重要作用。该结果精确定位PDAT与磷脂底物的结合位点以及催化位点，为下一步PDAT蛋白定向改造提供重要的数据支撑。     

2019年河北省进口棉花质量状况综合分析

通过对2019年河北省进口棉花的质量检验表明,2019年河北省进口棉花在品级、长度、马克隆值方面不合格率较2018年同期有所上升,以美棉品级不符合率最高,巴西棉整体质量好于上年、南非棉整体质量较差。同时介绍了2019年河北省进口棉花的基本情况及各进口国别的组成以及所占比例,分析了进口棉花中所带的有害生物情况和进口棉花量减少的原因。     

联合收获机粮箱内稻谷含杂率传感器采样盒设计

针对收割过程中通常只在开机时设置一次作业参数,不能经常停机观察籽粒的清洁度进而随时调节作业参数这一问题,需要研制一种能够自动获取联合收获机作业过程中含杂率数据的装置。但是,迄今为止,在收获过程中监测籽粒含杂率的研究还处于探索阶段。针对以上问题,结合联合收获机作业过程中谷物的流变特性,该文设计了一种谷物含杂率传感器,通过电磁铁(弹簧)控制挡板的伸出(复位),以使采样盒可视玻璃窗口前聚集(卸载)谷物,通过采样盒内CMOS相机获取数字图像,应用数字图像处理技术获得含杂率。依据图像直方图优化LED光源的照射及安装方法以获取高质量图像,分析了电磁铁提供的拉力和弹簧提供的推力、采样盒入口尺寸,采用全局阈值迭代算法,使用三个迭代步提取稻谷、茎秆和细柄连通域,计算每个连通域的像素,最终从形态上识别了谷物和杂质,同时测量稻谷千粒质量、茎秆面密度和细柄线密度,建立了计算谷物杂质质量的数学模型。结果表明:在采样盒内两侧各安装2个LED,间接照射视窗时获取的图像质量较好,有效避免了图像强度直方图中出现的峰值;额定拉力为60 N的电磁铁可以提供足够的拉力;采用线径为1 mm的弹簧能提供足够的推力,由于在收割过程中出现的短秸秆和细柄的长度在10 mm到30 mm之间,因此采样盒的设计高度为95.7 mm,宽度为76.5 mm,入口宽度为31.9 mm,视窗长度为57.1 mm,宽度为57.4 mm,如此稻谷、秸秆和细柄可以顺利流入采样盒,并且在视窗中可以看到约200粒谷粒。在不同含杂率下进行了籽粒含杂率传感器监测精度的台架试验,结果表明:该装置监测的籽粒含杂率与人工获得的籽粒含杂率具有一致的变化趋势,能够监测在0～2.88%范围内的籽粒含杂率。为了满足田间作业监测需求,同时设计了采样盒的防水防尘罩,为相机提供一个稳定抓取图像的工作环境。于2017年11月17日,在苏州九里湖进行了不同喂入量下含杂率监测试验,试验使用Yamma4LZ2.5联合收割机,结果表明,田间试验的相对误差在9.44%和19.67%之间。该研究可为田间收获过程中自动获取谷物含杂率提供参考。     

互叶白千层无性系区域试验研究

以前期选育的互叶白千层Melaleuca alternifolia 6个优树无性系为材料，在福建寿宁、广东东源、广西钟山开展区域性试验，通过测量生长与精油性状发现，生长性状（树高、地径、胸径和树冠截面积）、鲜叶含油量和精油中4-松油醇占比在无性系水平上以及地点间均存在极显著差异，表明精油资源林培育中无性系遗传特性与生境适应性均很重要。6个无性系精油中的4-松油醇占比均超过30%，即达到国家标准GB/T 26514-2011要求。综合选择指数分析结果显示，广西钟山适宜推广无性系YHB1、YHB2、 YHB3，福建寿宁适宜种植无性系YHB1和YHB2，广东东源适宜发展无性系YHB1、YHB2、YHB3和YHB4。     

污泥中不同铁盐对大叶茼蒿吸收重金属的影响

通过验证处理后的生活污泥在农作物上对产量和重金属吸收量的影响,以期为污泥实际应用积累基础。在盆栽条件下,通过7种不同的铁盐处理进行试验,从大叶茼蒿的生长情况、5种重金属积累量进行比较。结果表明：在不同铁盐处理中大叶茼蒿在污泥上的干物质有显著差异。处理CK、A、B、C干物质为3.59~7.49 g/盆,D、E、F为11.75~19.27 g/盆,处理D和B大小差别可达5.3倍。在正常情况下,污泥的重金属含量一般低于国家泥质标准。施用污泥的茼蒿重金属植株积累量Cu、As、Pb、Cd也在食品安全的标准范围内,但重金属Cr含量要超标4.98~6.66倍。施用污泥后茼蒿对某些重金属有较好的富集作用,但在产量上不同铁盐处理中以3%硫酸亚铁(FeSO₄·7H₂O)+2% FeCl₂处理最好,3% FeCl₃次之。     

Metabonomics analysis of Zi goose follicular granulosa cells using ENO1 gene expression interference

The Zi goose is native to North-east China and is noted for its high egg production. Alpha enolase (ENO1) is a glycolytic enzyme which functions as a plasminogen receptor in follicular granulosa cells (FGCs), with several studies showing that FGCs can support follicular development. By transfecting the ENO1 interfering plasmid (shRNA) into FGCs, ENO1 expression in these cells was downregulated, suggesting the successful knock-down of ENO1 in these cells. In this knock-down model, we detected 13 metabolites from FGCs using LC/MS. When compared with the non-coding shRNA (NC) group, the lower level metabolites were (R)-(+)-citronellic acid, altretamine, 3-hydroxycaproic acid, heptadecanoic acid, cholecalciferol vitamin D3, indole, benzoic acid, capric acid, caffeic acid, azelaic acid, 3,4-dihydroxyhydrocinnamic acid and cholic acid, while oleic acid was detected at high levels. To further examine the results of metabolomics, six key metabolites were verified by gas chromatography-mass spectrometry (GC-MS). We found that vitamin D3, indole, benzoic acid, capric acid and cholic acid were significantly downregulated in the shRNA group, while oleic acid was significantly upregulated. This observation was consistent with the metabolomics data. Through these studies, we found that decreased ENO1 levels altered certain metabolite levels in FGCs.     

Genetic characterization of anemone-type chrysanthemum (Chrysanthemum morifolium) using floral morphology and SRAP markers

An appreciation of the genetic diversity retained in the gene pool of anemone-type chrysanthemums is needed to drive further genetic improvement of this commercially important ornamental species. Here, a panel of 67 accessions was characterized with respect to both floral morphology, assessed using a set of 12 inflorescence-associated traits, and to genotype, using sequence-related amplified polymorphism (SRAP) fingerprinting. Abundant variation and a high level of broad-sense heritability (>88%) were revealed for all traits except number of tubular floret lobes. Of the possible 66 pairwise inter-trait combinations, 37 proved to be significantly correlated. A principal component analysis of the trait data showed that the first four principal components explained ~78% of the variance; meanwhile a hierarchical clustering analysis revealed a number of discrete groups reflecting the various cultivated types, but was not predictive of provenance. The SRAP genotyping employed 22 primer combinations and generated 238 informative fragments. A moderately high level of the Jaccard's similarity coefficient (mean 0.67) was calculated for the examined panel. A hierarchical clustering analysis based on the genotypic data revealed four groups, which were clearly reflective of cultivated type; moreover, a comparison of the within-cluster means for each of the two key anemone-related traits—tubular floret length and tubular floret length/style length—showed that the genotype-based clusterings were associated with the anemone levels, albeit imperfectively. A principal coordinate analysis showed that the first two coordinates accounted for about 14% of the total variation. In summary, the present study adds new understanding of the genetic diversity present in the anemone-type chrysanthemum gene pool, and the findings will lay the foundation for implementing a genotype/phenotype association strategy to reveal the genetic and molecular basis of floral form in this valuable ornamental species.     

白菜基可食性蔬菜纸的研究

研究了增稠剂添加量、甘油添加量和工艺条件对白菜纸性能的影响,通过优化试验,确定白菜纸的最佳配方和工艺。结果表明,海藻酸钠、玉米变性淀粉、明胶、CMC和甘油的最佳添加量分别为1.2%,3.0%,0.4%,0.4%,2%。最佳工艺参数为:干燥温度60℃,时间6h。以抗拉强度高为优选原则,得到最优的因素水平组合为:CMC添加量为0.4%,玉米变性淀粉添加量为1%,明胶添加量为0.2%,海藻酸钠添加量为1.6%。在此条件下,白菜纸的抗拉强度为5.98MPa。     

硫酸锌浸种对马铃薯幼苗质量的影响

以"克新13"马铃薯为材料,通过盆栽试验,利用不同浓度的硫酸锌浸种处理,考察马铃薯幼苗的壮苗指数、叶绿素含量、根系活力、蔗糖和还原糖的变化,研究硫酸锌对马铃薯幼苗质量及相关生理指标的作用效应。结果表明:适宜浓度硫酸锌(0.4g·L-1左右)浸种处理能有效地提高叶绿素含量和根系活力,提高壮苗指数,促进了叶片中蔗糖、还原糖的形成,改善幼苗质量。硫酸锌过量,则限制了马铃薯的壮苗指数,从而影响了幼苗质量及相关生理指标。     

无公害茶叶中亚硝酸盐残留分析及调控对策

本文简析了茶叶中亚硝酸盐残留的状况、规律及其成因。从科学使用氮肥、平衡施肥、精准施肥、培育低积累亚硝酸盐潜力的茶树种质资源等方面,阐述了无公害茶叶中亚硝酸盐残留的调控对策。