等离子体处理对亚麻籽胶结构和功能特性的影响

为了揭示等离子体技术对亚麻籽胶的物理改性效应,该研究以5 mg/m L亚麻籽胶溶液为对象,比较了不同等离子体处理时间(0～120 s)对亚麻籽胶结构和功能特性的影响规律。结果发现,随着等离子体处理时间的延长,亚麻籽胶溶液p H值、Zeta电位绝对值和平均分子量逐渐减小,而对亚麻籽胶的多糖骨架结构和单糖组成无明显影响。等离子体处理降低亚麻籽胶的炭化和聚合反应温度、表观黏度和界面吸附能力。冷场扫描电镜结合稳定性指数(Turbiscan Stability Index, TSI)结果显示,0～15 s等离子体处理在不明显降低亚麻籽胶中酚类化合物含量和体外抗氧化活性的同时,明显改善了亚麻籽胶构建亚麻籽油乳液的稳定性(P0.05)。因此,等离子体作为一种非热加工技术,能够用于亚麻籽胶的适度改性研究,以拓宽其在健康食品领域中的应用前景。     

异型雄性罗氏沼虾遗传多样性的微卫星分析

利用微卫星DNA标记研究3种近亲交配形态型雄性罗氏沼虾遗传多样性,所用虾样均采自国家级(南宁)罗氏沼虾良种场,共150尾成年近亲交配的雄虾,其中蓝色长臂型、橙色长臂型、小个体型各50尾。研究结果表明,3组样品的生长发育差异显著,蓝色长臂型、橙色长臂型、小个体型各组中微卫星位点的总等位基因分别为24、28和22,3组样品所有位点的平均观察杂合度为0.474～0.556。其平均群体内近交系数为-0.0189,说明杂合子过剩,对比分析和群体间分化系数表明,3组雄虾遗传差异明显,最大遗传间距位于蓝色长臂型和小个体型,最小的遗传间距位于蓝色长臂型和橙色长臂型。研究结果将为罗氏沼虾优质父本选育和调控雄性遗传发育提供基础性遗传信息。     

6种杀菌剂对番茄疮痂病菌的抑制作用

为了筛选防治番茄疮痴病的高效、低毒、低残留杀菌剂.采用菌丝生长速率法测定了6种杀菌剂对番茄疮痂病菌丝生长的抑制效果,并通过大田药效试验检测了防治效果.结果表明,植物性农药康地蕾得、新植霉素防治效果达83.36%～96.70%.0.2%～0.5%波尔多液抑菌圈半径2.36～3.72mm,防治效果达83.36%～100%.     

数字农业试验平台硬件设计

设计了数字农业试验平台车的硬件体系结构及其各个部分的组成结构.平台硬件体系由车载工控机子系统、运动控制子系统、视觉处理子系统和无线通信子系统等4个子系统(模块)组成.车载工控机系统采用研华一体化工作站-AWS-8248VTP,运动控制子系统由TI公司的TMS320LF2407A快速DSP运动控制芯片、步进电机和电机驱动器组成,视觉处理子系统由摄像头组成,无线通信子系统采用海信数码Hi-Link UW210g无线网络适配器,为数字农业技术的研究提供了较为理想的试验平台.     

大豆连作障碍机制研究初报

大豆连作减产早已为生产实践所证实。本文在对连作大豆减产规律调查研究的基础上,从大豆—土壤两个生态系统出发,对减产原因进行了分析,提出导致大豆连作障碍产生的原因是由土壤营养元素亏缺,物理、化学及生物活性改变,病虫害加剧等原因综合作用于大豆,使大豆生育受阻,产量下降。     

Dissecting Genetic Basis of Deep Rooting in Dongxiang Wild Rice

Deep rooting is an important trait in rice drought resistance. Genetic resources of deep-rooting varieties are valuable in breeding of water-saving and drought-resistant rice. In the present study, 234 BC₂F₇ backcross introgression lines were derived from a cross of Dongye 80 (an accession of Dongxiang wild rice as the donor parent) and R974 (an indica restorer line as the recurrent parent). A genetic linkage map containing 1 977 bin markers was constructed by ddRADSeq for QTL analysis. Thirty-one QTLs for four root traits (the number of deep roots, the number of shallow roots, the total number of deep roots and the ratio of deep roots) were assessed on six rice chromosomes in two environments (2020 Shanghai and 2021 Hainan). Two of the QTLs, qDR5.1 and qTR5.2, were located on chromosome 5 in a 70-kb interval. They were detected in both environments. qDR5.1 explained 13.35% of the phenotypic variance in 2020 Shanghai and 12.01% of the phenotypic variance in 2021 Hainan. qTR5.2 accounted for 10.88% and 10.93% of the phenotypic variance, respectively. One QTL (qRDR2.2) for the ratio of deep roots was detected on chromosome 2 in a 210-kb interval and accounted for 6.72% of the phenotypic variance in 2020. The positive effects of these three QTLs were all from Dongxiang wild rice. Furthermore, nine and four putative candidate genes were identified in qRDR2.2 and qDR5.1/qTR5.2, respectively. These findings added to our knowledge of the genetic control of root traits in rice. In addition, this study will facilitate the future isolation of candidate genes of the deep-rooting trait and the utilization of Dongxiang wild rice in the improvement of rice drought resistance.     

雷竹引种与丰产培育试验初报

通过引种雷竹,进行笋用竹林丰产栽培试验,探讨营林技术对其速生丰产的影响,结果表明:采用林地表土层以下深度30cm深翻耕作、深层施肥等措施后其优质经济竹(眉围≥9.60cm)可达65.0%以上,比对照提高18.6%~31.7%,新栽竹林套种农作物有利于促进雷竹笋用竹林速繁成林。     

Characteristics of Nitrogen Loss through Surface-Subsurface Flow on Red Soil Slopes of Southeast China

Soil nitrogen (N) loss related to surface flow and subsurface flow (including interflow and groundwater flow) from slope lands is a global issue. A lysimetric experiment with three types of land cover (grass cover, GC; litter cover, LC; and bare land, BL) were carried out on a red soil slope land in southeast China. Total Nitrogen (TN) loss through surface flow, interflow and groundwater flow was observed under 28 natural precipitation events from 2015 to 2016. TN concentrations from subsurface flow on BL and LC plots were, on average, 2.7–8.2 and 1.5–4.4 times greater than TN concentrations from surface flow, respectively; the average concentration of TN from subsurface flow on GC was about 36–56% of that recorded from surface flow. Surface flow, interflow and groundwater flow contributed 0–15, 2–9 and 76–96%, respectively, of loss load of TN. Compared with BL, GC and LC intercepted 83–86% of TN loss through surface runoff; GC intercepted 95% of TN loss through subsurface flow while TN loss through subsurface flow on LC is 2.3 times larger than that on BL. In conclusion, subsurface flow especially groundwater flow is the dominant hydrological rout for N loss that is usually underestimated. Grass cover has the high retention of N runoff loss while litter mulch will increase N leaching loss. These findings provide scientific support to control N runoff loss from the red soil slope lands by using suitable vegetation cover and mulching techniques.     

中国畜牧环境标准化体系建设浅析

畜牧环境是推动畜牧业跨越式发展的三大因素之一,但在实际生产中,对畜牧环境的重视不够,致使畜牧业发展受到限制。建立畜牧环境标准化体系是解决此问题的一个途径。该文主要简述了畜牧环境标准化的含义及其在畜牧业可持续发展与安全畜产品生产方面的重要作用。分析了目前我国畜牧业标准化方面存在的问题:畜牧环境标准体系建设有待完善、标准不统一、标准质量、标准的贯彻实施以及监测网络建设等问题。并在此基础上,提出了若干畜牧环境标准化建设的对策建议。     

盐碱胁迫下羊草消减文库的构建及分析

以盐碱胁迫下的羊草地上部分cDNA为实验方(tester),非盐碱条件下生长的羊草地上部分cDNA为消减方(driver),利用抑制性消减杂交技术(suppression subtractive hybridization,SSH)构建了盐碱胁迫下羊草消减文库.从消减文库中筛选1920个阳性克隆,PCR鉴定插入片段大部分集中在300～800 bp之间.将聚类后得到的552个非重复序列与GenBank中的序列进行比对,其中有548条与数据库中的序列有同源性,其中功能已知的339个,功能未知序列209条.获得了与盐碱胁迫相关的基因,如单脱氢抗坏血酸还原酶(MDAR)、γ-谷氨酰半胱氨酸合成酶(γ-ECS)、铁蛋白(Ferrtin)、水孔蛋白(PIP)、脱水素基因(dehydrin)、14-3-3蛋白等.本实验为抗逆基因的克隆及系统研究盐碱胁迫下羊草相关基因的表达奠定了基础.