九峰科技植物资源现状与保护对策

经过查阅历史档案、询问当事人及外业核查、调查,结果表明:九峰地区现有39块试验现场,面积124.7hm^2;实施各类科技项目53项,项目规模面积140.25hm^2,涉及裸子、被子等植物73科,150属,194种(类),已形成科技植物群体;在九峰森林植物本底调查、林木种质资源收集与保存、林木品种遗传改良及繁殖技术等13个学科方向及近120个植物品种开发研究方面取得了重大突破和创新;鉴于九峰科技植物资源现状,本文提出了相应的保护对策与措施。     

配电网检修计划优化实践

配电网设备检修能够及时发现常规试验或外观检查难以察觉的问题,使电网设备隐患或故障得到及时消除,通过合理有序安排检修工作,可有效提高电网的供电可靠性[1]。常规的检修计划制定过程通常包含分部门收集与汇总的过程,存在着潜在冲突与不合理之处,在实施之前,需要从技术与管理角度进行优化。     

浙南山区杨梅大棚促早栽培技术研究

本研究选择‘东魁’杨梅为试验材料，以露地栽培为对照，研究大棚设施促早栽培对‘东魁’杨梅的物候期、产量、品质、效益的影响效应。经过3年的试验，通过对‘东魁’杨梅物候期的记载，产量、效益的统计，单果质量、可溶性固形物、总糖、总酸、钾含量、Vc含量等质量指标的检测，综合分析结果表明，东魁杨梅大棚栽培促早、提质、增效效果显著。本研究对优化和推广杨梅大棚促早栽培技术具有重要意义，对山区农民增收提供示范案例。     

Comparative analysis of different methods revealing the involvement of proteins during ageing of rice seeds

Seed longevity is a very important characteristic controlling seed quality. However, the mechanism underlying this characteristic is poorly understood. In this study, 'FH7185', a storable rice variety, the germination rate of which was 66.63%, much higher than the control after artificial ageing under relative humidity 88% and 42°C for 21 days. Different methods were applied to reveal the involvement of proteins during ageing of rice seeds. In total, 35 differential proteins were identified from 2D‐PAGE, and 3,719 proteins from iTRAQ analysis. A comparison of these two methods showed that not all protein types could be detected on the 2D‐PAGE gels, and the dynamic range was somewhat limited. So the comprehensive proteome map from the iTRAQ analysis was used to identify the quantitatively regulated proteins that played roles in seed longevity, and found that the most marked change was the increased abundance of many metabolic enzymes, especially the ones involved in α‐linolenic acid metabolism in the embryos during ageing. OsLOX2 and OsLOX3 had a negative effect on seed longevity, which were lower in FH7185 than the control. The dehydrogenase (LOC_Os07g44430) which played a major catalytic role in lipid peroxidation, also changed significantly during ageing. Therefore, OsLOX2, OsLOX3 and Loc_OS 07G44430 may be involved in the regulation of seed longevity with a synergistic effect.     

驻极体对大肠杆菌的影响研究

为了有效防止空气中的大肠杆菌附着在食物等表面对人和动物造成腹泻等肠道疾病。以聚四氟乙烯制作的驻极体薄膜为试材,用控制变量法与理论分析和试验研究相结合的方法测得带负电和带正电的驻极体薄膜对大肠杆菌的影响数据。结果表明：带负电的驻极体薄膜对大肠杆菌的正常生长具有抑制作用,最高抑制率达到70.82%;带正电的驻极体薄膜促进了大肠杆菌的生长,最高促进率达到54.65%。进一步用光学显微镜观察到在带正电的驻极体薄膜下处理后的大肠杆菌菌落生长密集,带负电的驻极体薄膜处理后的菌落生长稀疏。驻极体薄膜对大肠杆菌生长造成影响的机制主要是静电场影响了大肠杆菌分子的膜电位,进而影响大肠杆菌的生长。带负电的驻极体薄膜对大肠杆菌具有良好的抑制作用,可为生产与驻极体灭菌有关的材料提供理论依据。     

基于迁移学习的棉花叶部病虫害图像识别

针对传统图像识别方法准确率低、手工提取特征等问题,该研究以棉花叶部病虫害图像为研究对象,利用迁移学习算法并辅以数据增强技术,实现棉花叶部病虫害图像准确分类。首先改进AlexNet模型,利用PlantVillage大数据集训练取得预训练模型,在预训练模型上使用棉花病虫害数据微调参数,得到平均测试准确率为93.50%;然后使用数据增强技术扩充原始数据集,在预训练模型上再训练,得到最终平均测试准确率为97.16%。相同试验条件下,该研究方法较支持向量机(Support Vector Machine,SVM)和BP(Back Propagation,BP)神经网络以及深度卷积模型(VGG-19和GoogLeNet Inception v2)分类效果更好。试验结果表明,通过迁移学习能把从源领域(PlantVillage数据集)学习到的知识迁移到目标领域(棉花病虫害数据集),数据增强技术能有效缓解过拟合。该研究为农作物病虫害识别技术的发展提供了参考。     

Potato absorption and phytoavailability of Cd,Ni, Cu,Zn and Pb in sierozem soils amended with municipal sludge compost

Effects of sludge utilization on the mobility and phytoavailability of heavy metals in soil-plant systems have attracted broad attention in recent years. In this study, we analyzed the effects of municipal sludge compost(MSC) on the solubility and plant uptake of Cd, Ni, Cu, Zn and Pb in a soil-potato system to explore the mobility, potato plant uptake and enrichment of these five heavy metals in sierozem soils amended with MSC through a potato cultivation trial in Lanzhou University of China in 2014. Ridge regression analysis was conducted to investigate the phytoavailability of heavy metals in amended soils. Furthermore, CaCl_2, CH_3 COONH_4, CH_3COOH, diethylene triamine pentacetic acid(DTPA) and ethylene diamine tetraacetic acid(EDTA) were used to extract the labile fraction of heavy metals from the amended soils. The results show that the MSC could not only improve the fertility but also increase the dissolved organic carbon(DOC) content of sierozem soils. The total concentrations and labile fraction proportions of heavy metals increase with increasing MSC percentage in sierozem soils. In amended soils, Cd has the highest solubility and mobility while Ni has the lowest solubility and mobility among the five heavy metals. The MSC increases the concentrations of heavy metals in the root, stem, peel and tuber of the potato plant, with the concentrations being much higher in the stem and root than in the peel and tuber. Among the five heavy metals, the bioconcentration factor value of Cd is the highest, while that of Ni is the lowest. The complexing agent(DTPA and EDTA) extractable fractions of heavy metals are the highest in terms of phytoavailability. Soil properties(including organic matter, p H and DOC) have important impacts on the phytoavailability of heavy metals. Our results suggest that in soil-potato systems, although the MSC may improve soil fertility, it can also increase the risk of soils exposed to heavy metals.     

β-carotene attenuates weaning-induced apoptosis via inhibition of PERK-CHOP and IRE1-JNK/p38 MAPK signalling pathways in piglet jejunum

Weaning may cause oxidative injury, immune response impairment, apoptosis and other injuries in piglets. Oxidative and endoplasmic reticulum stress (ERS) can elicit inflammatory responses, and persistent oxidative and ERS also may lead to apoptotic cascades, which is associated with the pathogenesis of multiple diseases. β-carotene, a natural carotenoid, has potential anti-inflammatory and antioxidant functions. However, the effect of β-carotene on apoptosis in weaned piglets and the detailed molecular mechanism remain unclear. In this study, we found that β-carotene decreased malondialdehyde (MDA) levels and increased the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in piglet serum. β-carotene could inhibit the mRNA levels of caspase-3 significantly, but had no significant inhibitory effect of the mRNA levels of caspase-9 and caspase-12 in the piglet jejunum. In addition, β-carotene decreased the activation of GRP78, CHOP, and JNK/p38 MAPK and the ratio of Bax/Bcl-2. Furthermore, β-carotene had a significant influence on the activation of ERS and apoptosis-related signals in TG-induced IPEC-J2. In the present study, β-carotene pre-treatment attenuated the ratio of Bax/Bcl-2 and prevented TG-induced increases in the level of PERK-CHOP and IRE1-JNK/p38 MAPK pathway activation in a dose-dependent manner. Overall, these findings indicate that β-carotene may protect weaning-induced apoptosis through inhibiting ERS.