Improvement of Appearance Traits of elite Rice Zhenshan 97B by Molecular Introgression of Targeted about 800 kb Interval from Indica Rice Jiafuzhan Genome

Rice appearance trait is mainly mean grain length (GL), grain width (GW), ratio of length and width (L/W), chalkiness (CH) and transparence (TR). Appearance is the first impression, and rice appearance traits effect significantly the value of commodity. Hybrid rice is relatively low quality, especially on rice appearance quality,which restricts partially its extend and badly export of hybrid seed and rice in China.Shanyou 63, the most famous hybrid rice combination of China, could not be also sustainable application because of its poor qualities. In this studies, We attempt to improve appearance quality of the elite rice maintainer of Zhenshan 97B by using molecular approach of genomic interval targeted introgression. Three F2 populations were constructed to study the classical and molecular genetic of rice appearance traits, at the same time, molecular marker-asisted toimprove the main maintainer line, Zhenshan 97B were performed. There some following results:Three F2 populations were constructed based on crosses of Guangluai 4×Jiafuzhan (GJ popu.), Minghui 86×Jiafuzhan (MJ popu.) and Zhenshan 97B×Jiafuzhan (ZJ popu.). ZJ popu and GJ popu were produced to reconstruct the linkage maps related with rice appearance traits based on BSA, and detect QTL of target traits based on IM.In ZJ popu, 9 QTLs of target traits were detected. The interval, RM169～RM516 on Chromosome 5, was genetic locus of GW, L/W, CH and BW, and the explained variances were 10.9%, 14.9%, 12.0% and 14.2%, respectively.RM214 on chromosome 7, RM339 on chromosome 8 were genetic loci if CH and BW, and the explained variances were 9.4%, 10.0%, 11.0% and 12.1%. besides there is a genetic locus, RM347, of G/W on chromosome 3, and the explained varance was 10.3%. In GJ popu, 5 QTLs of rice appearance traits were detected. The interval, RM169-RM516 on Chromosome 5, were also the genetic loci of GW, CH and BW, and the explained variances were 9.0%, 12.5%, and 13.6%, respectively. RM264～RM80 on chromosome 8 was the genetic loci of GW amd L/W,and the explained variances were 14.7% and 13.4%. The genotypes of all QTLs, except RM214, from Jiafuzhan contributed to improving riee appearance traits.The research was to improve the rice appearance quality of Zhenshan 97B by introgressing QTLs of rice appearance traits from Jiafuzhan, a donor parent, by means of MAS in the process of recurrent backcrossing, 4 SSR markers were used to detect the target genotypes from donor parent, and 70 SSR primers to identify the genetic background of recurrent parent. Consequently, there were 19 target individuals in BC3, in which the mean value of GL, GW, L/W, CH and BW were 6.06±0.04mm, 2.50±0.02mm, 2.43±0.02, 29.5±2.7 and 29.4±2.7%, respectively,and the mean homologous degree (HD) to recurrent parent is up to 98.22%. Compared to Zhenshan 97B, GL, CH and BW decreased 0.17 mm, 34.9% and 34.5% respectively and however L/W increased 0.19. which accounted separately for 25.37%, 54.79%, 54.57% and 10.50% of thedifference of every trait between two parents. It is very luckly to find a individual, 13BC2-3BC3 line, whose GL, GW, G/W, CH and BW were 6.04 mm, 2.43 mm, 2.49,2.5% and 2.5% separately, There is very important signification for it to be used in hybrid rice breeding improving appearance traits. In the research, MAS efficiency of 3 loci (with 4 markers ) was 5.68% and coincident degree was 73.08%.     

抗草甘膦棉花研究进展

抗草甘膦棉花最早于1997在美国释放,它是通过将编码抗草甘膦酶5-烯醇式丙酮酰莽草酸-3-磷酸合成酶基因导入珂字棉312而获得的抗性株.抗草甘膦棉花在美国的种植面积占棉花总种植面积从1997年的3.2%到增加到2005年的60%左右.在这近十年内,抗草甘膦棉花虽然得到了广泛的种植,但也存在着不少问题,其中最为突出的是草甘膦的施用方法和时期的不正确操作对抗草甘膦棉花的根系生长、育性和产量都产生了负面影响.这主要是因为:1、外界因素,包括草甘膦施用方法在内的其他栽培措施和不利的环境条件,如高温,对抗草甘膦棉花的产量及生长的影响;2、内部因素,抗草甘膦棉花不同器官对草甘膦的吸收量及抗草甘膦基因的表达量差异有关.因此,本文从抗草甘膦棉花对草甘膦的吸收分配、草甘膦的施用量和时期对抗草甘膦棉花根系生长、花药开裂及产量等方面综述了这些年来抗草甘膦棉花在应用过程中的问题,并且对今后抗草甘膦棉花育种方面作了展望.     

稻米食味品质形成及其响应氮素调控作用的研究进展

稻米食味品质是消费者评价稻米优劣的关键品质,决定了大米的档次与市场定位.本文阐述了直链淀粉含量、胶稠度、淀粉晶体结构、淀粉颗粒粒径分布、支链淀粉链长分布、淀粉溶解及膨胀特性、热力学特性、糊化特性及回生特性等稻米食味品质评价体系,从稻米淀粉合成相关酶(AGPase)、颗粒结合淀粉合成酶(GBSS)、可溶性淀粉合成酶(SS...     

中山市野生珍稀濒危植物和国家重点保护野生植物调查

据调查,中山市共有野生珍稀濒危植物7科7属7种,种数占广东省9.33%;国家重点保护野生植物7科7属8种,种数占广东省12.31%,并发现了极为罕见的四药门花、绣球茜和驼峰藤等种类.文章在介绍中山市野生珍稀濒危植物和国家重点保护野生植物的基础上,提出了保护建议.     

猫尾草的价值与栽培技术

文章介绍了猫尾草的形态特征及其实用价值,并总结了其栽培管理技术.     

农业院校学分制下导师职责定位

学分制由于在诸多方面有着传统的学年制所不可替代的优点而被许多农业院校采用.学分制下导师制的管理模式是其能否最终得到贯彻实施的关键要素之一.为此,导师应不断提高自身素养;要从"导向"、"导学"、"导心"及"导研"等层面给学生以具体的指导.同时,还应建立必要的激励和督导制度.     

广西青贮玉米生产的优势、问题及建议

发展青贮玉米对畜牧业发展具有积极的作用。通过实地调研和查阅有关资料发现,广西青贮玉米生产具有政策层面、生态环境、市场需求、优质饲料缺口大、效率高、品质好等方面的优势,但广西青贮玉米生产也存在缺乏优质专用型青贮玉米品种、技术落后、生产及收获加工机械化程度低和效率低等问题。广西要立足资源优势,用好用足各类支持和鼓励政策,制定适宜本地青贮玉米发展的具体措施,积极开展青贮玉米优质专用型新品种的选育和审定等科研联合攻关,推广应用青贮玉米新品种,强化青贮玉米种植生产的技术培训和展示观摩,提高青贮玉米生产的规模化和机械化水平,大力发展青贮玉米,促进畜牧业健康发展。     

果园巡检机器人长臂抖动抑制方法

针对果园巡检机器人长臂因抖动而严重制约图像采集效率的问题,该研究提出基于臂体上3个部位的仰角构建单一反馈量进行抖动抑制的方法。首先基于臂体外伸段的有限元模态分析结果,通过固有频率和静变形的等效,建立三杆两扭簧等效机构的动力学模型。并基于微分平坦理论将3个倾角传感器读数合成为一个系统输出量,以平坦输出量作为被控量,采用PID控制器进行抑振试验,再利用自抗扰控制(Active Disturbance Rejection Control, ADRC)思想中对广义扰动的处理方法,将被控模型等效为二阶系统形式,并将模型信息代入到扩张状态观测器中进行对比试验。试验结果表明,基于本文构建的方法均能起到快速抑制长臂抖动的作用。在冲击作用致使末端产生10°幅值的抖动情况下,PID控制器实现了7 s内抑制大幅抖动,自抗扰控制器实现了8 s内快速抑制大幅抖动的效果。PID控制器的输出出现3次饱和现象且小幅较高频率抖动不易消除,而自抗扰控制器仅出现一次饱和,具有抖动抑制过程平滑的优点。本文的控制算法简洁适于在单片机等微型计算机系统中应用,系统结构简单成本低,可为现代农业装备研发与应用中解决长臂类结构抖动的主动抑制问题提供理论参考。     

基于CNN-BiLSTM的棉花产量预测方法

针对传统的作物产量估算方法在模型泛化方面的不足及缺少时序特征和空间特征的问题,该研究以机采棉为研究对象,结合无人机遥感平台与深度学习技术对棉花进行多期遥感观测与估产。以棉花苗期、蕾期和花期的影像为时间序列数据集,构建基于卷积神经网络（Convolutional Neural Network,CNN）和双向长短期记忆（Bidirectional Long Short-Term Memory,BiLSTM）的混合模型（CNN-BiLSTM）进行棉花产量预估,提高时间维度和空间维度方面的特征提取能力,并分别验证CNN和BiLSTM的性能以及不同网络深度对估产的影响。研究结果表明,CNN和BiLSTM深度分别为14和1的CNN14-BiLSTM模型准确率最高,对比单一结构的BiLSTM该模型决定系数从0.851提升至0.885,其均方根误差和平均绝对百分比误差也均明显下降,在2.3 m×2.3 m的样方内,结果分别为147.167 g和6.711%。该研究实现了基于时间序列的棉花产量估算,可为类似的作物产量估算提供参考。     

基于生物酶法的酰基化桑椹花青素的制备与特性

为尽可能减少花青素的降解,提高其稳定性,采用生物酶法,对桑椹花青素进行酰基化修饰,并与非酰基化花青素进行对比研究。运用单因素试验筛选脂肪酶、反应溶剂和酰基供体,分析对花青素酰基转化率的影响。确定酰基化反应的优化条件为南极假丝酵母脂肪酶为酰基化催化酶、吡啶为催化反应溶剂、苯甲酸甲酯为酰基供体,酰基化效果最好,转化率最大为13.5%。采用傅里叶红外、高效液相色谱对产物进行分析,经鉴定,酰基化产物为单酰基或多酰基花青素。此外,研究了酰基化对花青素稳定性和抗氧化性的影响。酰基化可提高花青素的热稳定性、光稳定性和耐酸碱稳定性。相同温度下,酰基化花青素保留率提高约5.0%,光照6d后,酰基化花青素的保留率仍高达96.1%。酰基化可以显著增加花青素体外抗氧化性,增强DPPH自由基清除能力,总还原能力比非酰基化花青素提高30%,金属离子螯合能力高达90%。酰基化花青素肿瘤细胞活性抑制率可达81%,而非酰基化花青素仅为50%。该研究为花青素稳定性提高和性能改善提供参考的理论依据。