黄瓜新品种‘粤丰’

 ‘粤丰’是由早熟抗病的‘豫优4号’为母本，与‘渝亮3号’杂交育成的华北型黄瓜一代杂种。生长势强，主侧蔓结瓜，雌花节率高，回头瓜多。瓜条顺直、美观，长棒形，瓜长38.0 cm，横径3.8 cm，肉厚1.2 cm，单瓜质量约390 g，皮色深绿，光泽度好，刺白，瘤小而密，肉质脆，味微甜，商品性好，耐热，抗病、抗逆性强。适合华南地区春秋季种植。     

MicroRNA-145 inhibits epithelial-mesenchymal transition in human renal cancer A-498 cells by ADAM28

AIM: To investigate the inhibitory effect of microRNA-145 (miR-145) on epithelial-mesenchymal transition (EMT) in renal cancer A-498 cells. METHODS: The A-498 cells were transfected with miR-145 mimics (M145) and mimic negative control(MNC), which served as M145 group and MNC group, respectively. Mock control (MC) group was set up using untreated A-498 cells. The expression level of miR-145 in each group was detected by RT-qPCR. Transwell assay was used to detect the invasion ability of the cells. The protein expression of vimentin, E-cadherin and ADAM28 was determined by Western blot. Bioinformatic method was used to predict the target genes of miR-145. Antagonistic effect of ADAM28 over-expression on the inhibition of EMT by miR-145 was detected by Western blot. The relationship between miR-145 and ADAM28 was analyzed by dual-luciferase reporter assay. RESULTS: The expression level of miR-145 in M145 group was significantly up-regulated than that in MC group (P<0.05). The number of invasive cells in M145 group was 12.78±3.37, which was significantly lower than that in MC group (P<0.05). ADAM28 may be the target gene of miR-145. Compared with MC group, the protein expression of vimentin and ADAM28 in M145 group was significantly decreased (P<0.05), while the protein expression of E-cadherin was significantly increased (P<0.05).After ADAM28 over-expression, the protein expression of vimentin in the A-498 cells of M145 group was significantly increased (P<0.05), and the protein expression of E-cadherin was significantly decreased (P<0.05). The results of dual-lucife-irasei reporter assay showed that ADAM28 was a downstream target gene of miR-145. CONCLUSION: miR-145 may inhibit the expression of EMT-related proteins through the downstream target gene ADAM28 and inhibit the EMT process of renal cancer A-498 cells.     

Impact of the COVID-19 pandemic on agricultural exports

The COVID-19 outbreak has shocked the world's economies in the year of 2020. As this pandemic spreads around the globe, many experts feared that the global food supplies might start running short, especially if supply chains were disrupted. COVID-19 also added to the uncertainty of the business operation. Therefore, it is critical to understand how COVID-19 pandemic affected global food supply and market. In this study, we investigate the impact of COVID-19 on agricultural export companies in China using a unique firm-level survey data. We found that although on average agricultural businesses experienced declines in the exports, exports of some agricultural products especially grain and oil held strong and even increased, implying the essential demand for staple food during the pandemic. Not surprisingly, exports of medicinal herb also increased significantly during the pandemic. However, exports of goods such as edible fungus and horticultural products sharply decreased. Our results also showed that in general, impact of COVID-19 on smaller firms was more severe than that on larger firms. The results of this study can provide useful guidance and implications for agricultural businesses and policy makers on their COVID-19 mitigation efforts to navigate this global pandemic.     

厚叶南五味子仿生态栽培关键技术研究

选取厚叶南五味子应用试验方法,进一步筛选优良扦插技术、壮苗培育技术方案和立体种植关键技术措施,结果表明:厚叶南五味子扦插技术在70％透光率的塑料大棚内扦插50 d,可获得优良的扦插苗,取得最佳的生长效果;壮苗培育技术最优基质配比为碎石:腐烂树皮:碎木屑(1:2:1)+1.5 kg/m3缓释肥+4.0 kg/m3腐熟饼肥;立体附植应以240 d的壮苗在3月份进行.     

右江流域水生态补偿机制研究初探

为保护右江流域生态环境,协调郁江乃至珠江上下游各方经济利益,更好的激励上游地区生态环境保护行为,通过分析右江流域水生态现状、存在问题、现有生态补偿政策环境及其在郁江流域、珠江流域中的地位和作用,利用外部性理论,分析提出了右江流域水生态补偿模式。通过对标对表有关生态保护规划和区划成果,立足百色市实际,提出了右江流域水生态补偿内容、补偿主客体、补偿标准和补偿方式,初步构建右江流域水生态补偿机制框架,并提出有针对性的补偿政策建议,为水生态补偿实施提供了参考。     

生物炭对酸化茶园土壤性状和真菌群落结构的影响

为探讨生物炭长期施用对酸化茶园土壤改良和真菌群落结构的影响,分析了按生物炭用量0、2.5、5、10、20、40 t·hm^-2施用5年后的茶园土壤性状和真菌群落结构变化。结果表明,施用生物炭5年后的茶园土壤pH提高了0.16~1.11,可溶性有机碳含量提高了52.6%~92.3%,而铵态氮和硝态氮含量以10 t·hm^-2处理最高。施用生物炭5年后的土壤性质变化,进一步影响了真菌群落结构,表现为Chao指数、ACE指数和Shannon指数随生物炭用量增加呈先增加后降低的趋势;提高生物炭施用量对茶园土壤次要作用的真菌（LDA值<3.50）丰度的增加效果高于优势真菌（LDA值>3.50）的效果,其中被孢霉属、木霉属、毛壳菌属的相对丰度增加,黑盘孢属的相对丰度降低。     

河北省杂粮生产现状及生产布局展望

河北省是杂粮生产大省,且种类繁多。为稳定河北省杂粮生产发展,进一步调整河北省种植业结构提供参考依据,本文总结了河北省杂粮的历史生产现状,包括面积、单产、总产以及河北省各地市杂粮的分布,试图探索杂粮的生产布局与趋势,同时针对河北省杂粮历史单产水平变化趋势,分析了造成单产变化的成因,并简单提出建议。最后提出河北省杂粮生产布局的展望,将河北省杂粮生产区域布局划分为优势主产区、战略提升区、稳步发展区三个功能区。     

中国奶牛养殖生产布局优化研究——基于比较优势的实证分析

科学分析奶牛养殖区域比较优势,是优化中国奶牛养殖生产布局的前提条件。利用2001-2017年中国乳业数据,通过面板数据模型分析影响中国奶牛养殖生产布局的关键因素,基于比较优势理论、采用资源禀赋系数法,针对关键因素进一步分析中国奶牛养殖区域比较优势,探讨中国奶牛养殖生产布局的优化方向。研究结果表明:中国奶牛养殖生产布局主要受到玉米产量、生产者预期和温度的影响,不同地区在这三个方面具有不同的奶牛养殖比较优势。奶牛养殖优势区域主要集中在华北产区和西部产区,包括内蒙古、河北、山西、新疆、甘肃和宁夏;非优势区域主要集中在南方产区,包括上海、江苏、浙江、福建、湖北、湖南、广东、四川、安徽、江西和广西;其余省份为较优势区域,主要集中在东北产区和大城市周边产区。因此,从区域发展层面,提出建设优势区域产业带、因地制宜发展较优势区域、引导非优势区域转移和整合区域资源优势等建议;从奶牛养殖生产布局显著性影响因素层面,提出推广种养结合养殖模式、种植替代玉米的饲料作物、引导乳制品消费、改善养殖基础设施等建议。     

优化提取裸花紫珠总黄酮含量及对表皮伤口易感染菌抑菌性的研究

为了选出裸花紫珠总黄酮提取的最优方法,比较了ASE、超声、微波萃取和多功能浓缩4种提取方法在裸花紫珠总黄酮提取率上的差异,并利用微孔刃天青法测定总黄酮对表皮易感染菌的MIC值。结果发现ASE法总黄酮提取率最高,约为1.26%,其次为超声和微波萃取法,总黄酮提取率分别约为1.03%和0.98%,多功能浓缩法提取率最低,约为0.36%,且耗时最长。而且研究发现,ASE的MIC值最低。最终得出ASE提取效率最高,且提取物有较好的抑菌性,是裸花紫珠总黄酮提取的最优方法。