茶树花青素形成分子机理的研究进展

花青素是由类黄酮合成途径产生的次生代谢产物,含量高时会使茶树新梢呈现红色或紫色。同时,花青素相比儿茶素等具有更明显的抗氧化、预防肿瘤等药理保健作用。文章就茶树花青素合成途径、转录及转录后调控等方面进行综述,以期更好地为高花青素茶树的育种研究提供理论依据。     

TCD燃烧系统对柴油机燃烧和排放性能改善效果的试验研究

为探究道依茨TCD2015柴油机上配备的导流燃烧系统(简称TCD燃烧系统,T表示涡轮增压器,Turbocharger,C表示进气中冷,Charge air cooling,D为柴油颗粒捕集器,Diesel particle filter)对改善柴油机燃烧性能和降低污染物排放的效果,采用单缸机试验对TCD燃烧系统在不同转速、负荷和过量空气系数下的燃烧和排放性能进行研究。试验结果表明不同工况下TCD燃烧系统燃油消耗率和Soot排放量均低于传统ω燃烧系统,燃油消耗率最大降幅为7.01%,Soot排放量最大降幅为86.67%,且低过量空气系数(1.2～1.6)下TCD燃烧系统仍具有较好的性能。为揭示TCD燃烧系统改善油气混合促进燃烧的机理,采用AVL Fire软件建立了柴油机性能仿真模型。计算结果表明,TCD燃烧系统的环状凸起结构将燃油导向内外两室,从而促进了缸内燃油发展过程,燃油当量比大于4的浓混合气区域燃油质量比例相比ω燃烧系统降幅最大为9.75%,活塞下移时TCD燃烧系统内油束撞击浅盘侧壁形成撞壁射流扩大了燃油扩散面积,从而改善了缸内油气混合质量,燃油当量比小于1的均匀混合气区域燃油质量比例相比ω燃烧系统降幅最大为7.45%,因此TCD燃烧系统能够有效改善柴油机的燃烧和排放性能,可应用于柴油机高负荷和低过量空气系数工况综合性能提升。研究结果可为柴油机燃烧系统开发和改进提供参考。     

浙江安吉县实施毛竹收购价格指数保险的实践

近年来，随着劳动力工资水平的快速提高以及一系列严格的环保政策的出台，浙江安吉县毛竹收购价格持续走低并在较长时期处于低价徘徊，直接影响了竹农的经济收入和生产管理的积极性，出现了毛竹林抛荒失管现象。为保障竹林经营者的基本收益，扶持竹产业健康持续发展，安吉县探索实施了毛竹收购价格指数保险措施。文章介绍了安吉县毛竹收购价格指数保险的提出、方案设置以及实施2年来的实践情况，探讨了该保险所发挥的作用，提出了进一步改进的建议。     

Suramin alleviates hypertrophic scar in mice by inhibiting fibroplasia and inflammatory response

AIM: To investigate the therapeutical effect of suramin on hypertrophic scar (HPS) and its mechanism. METHODS: After the mouse model of HPS was established by mechanical stretching, the suramin solution at low dose (5 mg/kg) and high dose (10 mg/kg) was applied onto the scar site caused by mechanical load in mice by transdermal administration once a day for 10 d. The degree of scar hyperplasia was observed by macroscopy. The scar cross-sectional area and scar elevation index in the HPS tissues were evaluated by hematoxylin-eosin (HE) staining. The expression levels of transforming growth factor-β1 (TGF-β1) and interleukin-6 (IL-6) in HPS tissues were detected by immumohistochemical staining. The expression level of α-smooth muscle actin (α-SMA) in HPS tissues was detected by immunofluorescence staining, RT-qPCR and Western blot. The levels of tumor necrosis factor-α (TNF-α), IL-6, IL-10 and TGF-β1 in the HPS tissues were measured by ELISA. RESULTS: Macroscopic observation showed that the surface areas of scar in the HPS mice after treatment with suramin at low and high doses were significantly reduced (P<0.01). HE staining results showed that the scar cross-sectional area and the scar elevation index of HPS mice after treatment with suramin at low and high doses were significantly reduced (P<0.05 or P<0.01). The results of immunofluorescence staining, RT-qPCR and Western blot showed that the number of α-SMA positive cells and the mRNA and protein expression of α-SMA in scar tissues of HPS mice after treatment with suramin at low and high doses were significantly decreased (P<0.05 or P<0.01). The results of immunohistochemical staining showed that the expression levels of TGF-β1 and IL-6 in scar tissues of HPS mice after treatment with suramin at low and high doses were significantly reduced (P<0.01). The results of ELISA showed that the levels of TNF-α, IL-6, IL-10 and TGF-β1 in the scar tissues of HPS mice after treatment with suramin at low and high doses were significantly reduced (P<0.01). CONCLUSION: Suramin inhibits the formation of HPS, which may be related to the inhibition of fibroplasia and reduction of local inflammatory response.     

一氧化碳(CO)在植物体内的生理生化作用研究进展

为了促进一氧化碳(CO)在植物生理生化方面的研究,本文归纳了CO在植物体中的生物合成途径,CO作为信号分子对植物各种生理功能的调控,以及CO与其他信号分子之间的相互作用。经过分析得出,CO在植物生物胁迫过程中的作用及其作用机制方面的研究还很少,因此,CO在这方面的研究将会成为今后的研究重点。     

水分胁迫对花生不同器官非结构性碳水化合物含量的影响

为探讨不同生育时期水分胁迫对花生不同器官非结构性碳水化合物(NSC)“库—源—流”间的变化动态,以‘花育20号’和‘花育27号’花生品种为试材,采用控制条件下的防雨棚池栽方法,研究了花生生长发育过程中不同生育时期水分胁迫下,非结构性碳水化合物(NSC)在花生叶片、茎、根和荚果等器官中的动态变化。结果表明,全生育期干旱胁迫使花生叶片、茎和根中可溶性总糖含量和淀粉均明显升高,但荚果中可溶性糖含量却明显降低。无论何生育时期受到干旱胁迫均使得叶片中可溶性糖含量峰值提前15天左右出现,“源”物质输出提前但输出量降低,叶片提前衰老。生育前期干旱胁迫使滞留在荚果中的NSC含量增加,结荚期后干旱胁迫反而利于荚果中NSC的转化。全生育期水分适宜处理叶片中NSC含量相对较低且变化较小。由此表明,干旱胁迫降低了NSC由源至库的运输和转化,使荚果“库”容量降低。     

菊花新品种‘东篱雅致’

菊花新品种‘东篱雅致’是以中国传统大菊品种‘绿朝云’为母本，以花形奇特、不同色系的‘钟声’，‘清水莲’和‘笑靥’等传统大菊品种作父本进行人工混合授粉，经连续选择育成。舌状花松针形，粉、绿复色。植株低矮, 直立性强, 适于盆栽观赏, 主要观赏期11月中旬—下旬，可以用于北京地区节日布展或庭院观赏。     

Hormonal changes play important roles in the key period of superior and inferior earshoot differentiation in maize

The upper earshoots with higher superiority usually have higher yield potential and higher efficiency. To determine the key period for the asynchronous differentiation of superior and inferior earshoots and how hormones are involved in this process, a two-year experiment was designed using two maize hybrids: Suyu 41 (S41, single-ear hybrid) and AN 101 (A101, double-ear hybrid). The results showed that the lag of lower earshoot differentiation was not only caused by the delay of the differentiation starting time but also related to extension of the duration in spikelet differentiation (stage II) and sexual organ formation stage (stage IV). From 12 days before silking (DBS), the contents of indole-3-acetic acid (IAA), zeatin riboside (ZR)+zeatin (ZT), and gibberellic acid (GA₃) in both upper and lower earshoots of the two hybrids increased dramatically and then decreased quickly. ABA slightly increased in the two hybrids and then decreased slowly in S41, while it was maintained at a high level in A101. At 8 DBS, i.e., the transition period from floret differentiation to sexual organ formation stage, not only the growth of upper-to-lower earshoot difference (ULED), but also the values for ULED of IAA, ZR+ZT and GA₃ were all significantly higher in S41 than in A101. Furthermore, the upper-to-lower hormone ratios IAA_U//AA_L and (ZR+ZT)_U/(ZR+ZT)_L were also much higher in the single-ear hybrid than in the double-ear hybrid, while the GA_3U/GA_3L and ABA_U/ABA_L had no significant differences. In addition, the time course of ULED_hormone/ULED_{earshoot growth rate} also suggested that the hormones work in different ways in earshoot superiority/inferiority formation. The delayed differentiation of lower ear shoots was conclusively related to the later initiation of differentiation and the longer durations of specific differentiation stages. Compared with the regulating roles of IAA and ZR+ZT in the key period (8 DBS) of superiority/inferiority differentiation, GA₃ seems to be affected earlier, while ABA contributes little to this process.     

基于声振信号对称极坐标图像的苹果霉心病早期检测

为实现苹果早期霉心病较高精度的检测，该研究采用对称极坐标法（Symmetrized Dot Pattern，SDP）将苹果声振信号变换为雪花图，然后采用AlexNet、VGG16和ResNet50卷积神经网络以迁移学习方式深度挖掘SDP雪花图像的特征信息，将其输入到支持向量机（Support Vector Machine，SVM）分类器，对霉心程度≤7%的苹果进行检测。研究结果表明，当时间间隔系数为25和角度放大因子为50°时，健康果与早期霉心果声振信号的SDP图形状特征差异最大，在此条件下获取的SDP图经卷积神经网络AlexNet、VGG16和ResNet50提取特征并构建了不同核函数的SVM霉心果检测模型，在各类SVM模型中，ResNet50-SVM-gaus（高斯基）模型用相对较少的训练时间和参数量可取得训练集霉心果较高分类准确率，经超参数优化训练该模型对健康果和早期霉心果测试集不平衡样本（10∶1）的总体分类准确率达到96.97%，平均查准率、平均查全率、平均加权调和均值、Kappa系数和马修斯相关系数值分别为80.19%、90.36%、86.21%，82.54%和82.68%，该模型不仅对多数类的健康果保持较高分类准确率，而且对少数类的早期霉心果也具有较高判别能力。这些研究结果为声振法应用于果蔬内部病害的早期在线检测系统研发提供了技术支撑。     

Exploring patterns of Camellia seed cake application in relation to plant growth,soil nematodes and microbial biomass

ABSTRACT

The suppression of plant-parasitic nematodes is crucial for maintaining the worldwide development of the banana industry. In this study, different application patterns of Camellia seed cake previously reported to suppress root-knot nematode were conducted to manage pests and promote banana seedling growth. The results demonstrated seven days delay before transplanting was necessary after Camellia seed cake application. The dose 5 g/kg soil resulted in best plant growth promotion performance, which increased banana seedling height, stem diameter, shoot, and root fresh weight by upto 29%, 27%, 47%, and 21%, respectively. Plastic film mulching was beneficial when high amount (2%) of Camellia seed cake was added. The application of Camellia seed cake increased nutrient potassium amounts; the abundance of soil free-living nematodes, especially bacterivores; and the abundance of soil microbes and the soil catalase activity, while reduced plant-parasitic nematodes amounts. Further correlation analysis between the soil nematodes and microbial abundance showed that plant-parasite numbers had significant negative correlations with the bacterial biomass and a portion of the fungal biomass; bacterivores had significant positive correlations with the bacterial biomass; and omnivores had significant correlations with the bacterial biomass and fungal biomass. A fundamental challenge of root-knot nematode control is to sustain ecological services without losing biodiversity. This study provided an environmentally friendly strategy based on Camellia seed cake to regulate the soil health and quality.