Subspecific Characteristics and Classification of Rice Varieties Developed Through Indica and Japonica Crossing

Six characteristics, i.e., hull color, chaff and leaf pubescences, length of 1st and 2nd rachis, grain length/width ratio andphenol reaction, of rice progenies from indica and japonica crossing were studied using the Chengs index classificationmethod. The results indicated that F1 generations performed more like indica, while F2 generations were approximately ina normal distribution. Both of the rice progenies were more affected by indica and female parents than by japonica andmale parents. Among the six Chengs index traits of the parents and F1 generations, and between the traits and Chengsindexes, significant correlations (both at a=0.05 and a=0.01) were found in most cases. No significant correlations werefound among the 6 Chengs index traits of F2 generations in most cases, but significant correlations (a=0.01) existedbetween these traits and Chengs indexes. The six Chengs index traits of F2 ranged successively, and many individualsshowed over-parent genetics, with the same trends in both direct cross and reciprocal cross. Among the 6 index traits,chaff and leaf pubescences almost presented in a two-peak value, while the others in a mono-peak value. The hull color,phenol reaction and length of 1st and 2nd rachis were distributed in deviation, with the first two traits presented more injaponica individuals and the last trait more in indica. The grain length/width ratios were nearly in a normal distribution.

Genetic analysis of quality traits in intersubspecies crosses of rice

Indica and japonica rices are two subspecies ofAsia cultivated rice.Their grain qualities exista significant difference.The objective of thispaper is to study the genetic control of qualitytraits in intersubspecies crosses of rice.In 1991,4 japonica varieties with widecompatibility,PC311,Zhenxiqiuguang,Lun-hui 422,and Ce 03 were crossed with 5 indicavarieties,3037,Zaoxiandang 18,IR36,Minghui 63,and Yangdao 4 according to NC(?)design.The 20 hybrids using japonica as ma-

Distribution of the Classification Traits in the F_2 Progeny of Two Crosses of indica/japonica in Rice (Oryza sativa)

Comparison of seed setting rate, plant height and Cheng's morphological traits were made between the F_2 progeny of indica-japonica hybrids, 02428/Pei'ai 64 and Taichung 65/Teqing. There existed resemblance normal distribution in plant height, and the distribution had no relationship with the seed setting rate and plant height in F_1 progeny, suggesting that there were no gametic selection for the plant height in the F_2 progeny of indica-japoniea hybrids. An average seed setting rate of the F_2 was equal to the F_1 populations in the recombination of 02428/Pei'ai 64 in which there was an excellent cross compatibility, but the remarkable increase in the seed setting rate from the F_1 to F_2 in Taichung 65/Teqing, indicating that gametic selection only took place in the indica-japonica crosses with low cross compatibility while null or little in the hybrids with high compatibility. There were many intermediate types among the leaf pubescence, color of hull at heading, and length of the first and second panicle internode, and these Cheng's morphological traits was distributed normally; there were also a little intermediate types in hull hairness and phenol reaction with bi-peak distribution; while length to width ratio of grain was inclined to the japonica types obviously showing a skewed distribution in the F2 population. Although Cheng's morphological traits in F_2 populations had inconsistent distribution types, Cheng's morphological traits index showed normal distribution, which suggested that intermediate types, i.e. indicalinous or japonicalinous, were primary in F_2 population.

基于YOLOv5-RF的糙米内部裂纹识别方法研究

[目的]为准确识别糙米内部裂纹,提出了一种基于改进YOLOv5l的糙米裂纹识别算法——YOLOv5-RF。[方法]使用深度卷积代替CBS(convolution+batch normalization+sigmoid linear unit)模块中的普通卷积构建出DWBS(depthwise convolution+batch normalization+sigmoid linear unit)模块,然后将DWBS模块堆叠成辅助骨干网络,再与原始的Darknet-53主干网络相结合形成基于DWBS模块的同级复合骨干网络,以提高糙米内部裂纹特征提取能力;在颈部网络使用逆向连接层来增强解码端特征的丰富性,用于提高解码端对糙米内部裂纹的识别能力;利用CBAM(convolutional block attention module)注意力模块调整SPPF(spatial pyramid pooling-fast)模块的通道注意力表达,通过构建一种SPPF模块与CBAM模块结合的网络结构来提高编码阶段的语义信息表达质量。[结果]所提出的YOLOv5-RF算法的平均准确率、召回率和准确率分别为94.01%、86.92%、90.85%,相比YOLOv5l算法分别提升了4.72%、6.23%、1.23%,但添加模块对模型检测速度的影响却很小。[结论]所提方法能够准确进行糙米内部裂纹的识别,可为稻谷爆腰率检测提供技术参考。

An Insect Imaging System to Automate Rice Light-Trap Pest Identification

Identification and counting of rice light-trap pests are important to monitor rice pest population dynamics and make pest forecast. Identification and counting of rice light-trap pests manually is time-consuming, and leads to fatigue and an increase in the error rate. A rice light-trap insect imaging system is developed to automate rice pest identification. This system can capture the top and bottom images of each insect by two cameras to obtain more image features. A method is proposed for removing the background by color difference of two images with pests and non-pests. 156 features including color, shape and texture features of each pest are extracted into an support vector machine （SVM） classifier with radial basis kernel function. The seven-fold cross-validation is used to improve the accurate rate of pest identification. Four species of Lepidoptera rice pests are tested and achieved 97.5% average accurate rate.

Genetic Analysis and QTL Mapping of Large Flag Leaf Angle Trait in Japonica Rice

Genetic segregation analysis for flag leaf angle was conducted using six generations of P1, P2, F1, B1, B2 and F2 derived from a cross of 863B （a maintainer line of japonica rice） and A7444 （a germplasm with large flag leaf angle）. Genotypes and phenotypes of flag leaf angle were investigated in 863B （P1）, A7444 （P2） and 141 plants in BC^F~ （863BIA744411863B） population. An SSR genetic linkage map was constructed and QTLs for flag leaf angle were detected. The genetic map containing 79 information loci was constructed, which covers a total distance of 441.6 cM, averaging 5.6 cM between two neighboring loci. Results showed that the trait was controlled by two major genes plus polygene and the major genes were more important. Fifteen markers showed highly significant correlations with flag leaf angle based on single marker regression analysis. Two QTLs （qFLA2 and qFLA8） for flag leaf angle were detected by both composite interval method in software WinQTLCart 2.5 and composite interval method based on mixed linear model in QTL Network 2.0. The qFLA2 explained 10.50% and 13.28% of phenotypic variation, respectively, and was located at the interval of RM300 and RM145 on the short arm of chromosome 2. The qFLA8 explained 9.59% and 7.64% of phenotypic variation, respectively, and was located at the interval flanking RM6215 and RM8265 on the long arm of chromosome 8. The positive alleles at the two QTLs were both contributed from A7444.

Estimating Out-Crossing Rate of Bg 379-2 Using Morphological Markers and Confirmation by Molecular Markers

Rice is largely self-fertilized and accordingly a field population of rice is completely composed of near homozygotes. Due to the emergence of off-types, homozygosity will be affected. With the time, this will cause the reduction of genetic purity in some rice varieties. One of the reasons has been suspected to be the high out-crossing frequencies of such varieties. Studies were conducted at the Rice Research and Development Institute, Batalagoda, Sri Lanka to estimate the out-crossing rate of Bg 379-2, a variety having the problem of maintaining genetic purity. Bg 379-2 was allowed to out-cross with Bg 450 and the number of out- crossed plants were counted using dominant morphological markers such as short-round grain and purple culm of pollen donor. A molecular confirmation of out-crossing was also performed using sequence tagged site （STS） molecular marker pTA248. The variety Bg 379-2 showed a potential out-crossing rate of 3.41% and an average out-crossing rate of 1.29% using dominant morphological markers. Polymorphism was cleady detected between parents and out-crossed plants as well as selfed plants of Bg 379-2 using their banding patterns. A similar study can be performed to determine the out-crossing rates of other varieties which show high percentage of off-types in the population for the better understanding of the breeding behavior of the varieties.

Rice公式外推桥梁荷载效应

在当今,如何对桥梁进行合理评估已成为桥梁工作者的一个重要课题。而在桥梁评估过程中,科研工作者往往需要定量描述评估周期内某座桥梁的交通车辆荷载大小,一般用荷载效应描述。就此根据动态称重系统实测的107国道路段交通荷载数据产生的模拟车流对评估周期内荷载效应极值的计算方法进行了初步研究,以各种跨径简支梁为例,利用Rice外推理论外推各个观测周期的荷载效应极值,并以此作为建立评估荷载模型的基础。

便捷式智能化大米新鲜度检测系统设计与应用

目的:实现大米新鲜度的快速无损检测。方法:研制一套基于纳米色敏传感器结合近红外光谱分析原理的便携式装置系统。对所采集到的不同掺陈度大米样品所对应色敏传感器的光谱数据,进行多梯度掺陈大米的鉴别与跨批次大米新鲜度的预测。结果:使用Si-CARS-PLS提取光谱特征变量,经LDA算法建模后判别模型的识别率最高,训练集和预测集的识别率分别为97.22%和95.83%。同时,PLSR模型预测跨批次数据具有更强的稳定性,不同批次大米样品数据训练集和预测集的相关系数(R_(c)、R_(p))均稳定在0.95左右,均方根误差(RMSEC、RMSEP)均低于0.2,相对分析误差(RPD)均大于3。结论:该系统具有准确率高、便捷和预测模型鲁棒性好等特点,在大米新鲜度的现场检测中有很好的应用前景。

水稻粒型调控基因功能研究进展

水稻是世界上的重要谷类粮食作物之一,其产量和品质一直都是育种学家关注的重点,关系到全球粮食安全和人类健康。水稻粒型主要包括粒长、粒宽、粒厚等,是受多基因控制的重要数量性状,不仅直接影响水稻产量,还与水稻品质密切相关。深入了解水稻粒型的形成与调控机理将有助于进一步提升水稻单株产量、改善稻米品质。分子生物学的发展和基因组学的研究为探究水稻内部调控机制带来了新的变革。大量水稻粒型的数量性状遗传位点(Quantitative trait locus,QTL)成功被鉴定与解析,并验证了与之有关的基因功能。目前,已有几条调控粒型的通路得到鉴定,如泛素-蛋白酶体降解途径、G蛋白信号途径、丝裂原活化蛋白激酶途径、转录因子调控途径、植物激素途径以及表观遗传途径等。然而,粒型调控网络极其复杂,多数基因上下游的调控组件作用机制尚不清楚,甚至影响粒型的各条通路间均存在一定的交叉互作。本文综述了影响水稻粒型的不同信号通路相关基因研究进展及关键粒型基因间的互作关系,总结了近年来粒型基因在育种上的应用情况,并提出结合多组学解析水稻粒型的调控机理研究,以期更好地服务于分子设计育种,为开发新的高产优质稻育种提供支撑。

谷氨酰胺酶催化交联大米蛋白对大米淀粉理化特性的影响

为弄清谷氨酰胺酶(TG)催化交联前、后大米蛋白对大米淀粉理化特性的影响,测定淀粉的膨胀系数与溶解度、直链淀粉溢出率。采用红外光谱法、可见分光光度法、差示扫描量热仪(DSC)、快速粘度分析仪(RVA)等技术手段分析淀粉共混体系的结构特征和功能特性。结果表明,蛋白在TG酶催化下对淀粉的结构、消化率与其它功能特性均有显著影响,且大米蛋白与淀粉二者间相互作用增强,表现为:大米淀粉的膨胀系数由13.24 g/g降至最低,为7.02 g/g,其直链淀粉溢出量降低38.7%。在TG酶作用下,随着蛋白含量的增加,淀粉短程有序结构的稳定性逐渐增强。添加量为10%的蛋白在TG酶的催化下对淀粉消化性减轻效果更好。TG酶作用前、后蛋白对淀粉的热特性影响不大,而其糊化特性参数均明显下降,黏度也显著降低。TG酶催化蛋白使得淀粉颗粒网络结构更加致密且聚集。结论:TG酶催化交联蛋白对淀粉的改性效果显著。

云南蒙自过桥米线的品质测定

本文以蒙自地区主要生产企业的市售米线为研究对象,测定其理化指标、质构特性、感官品质,以期得到理化指标与米线品质的相关性。结果表明,过桥米线理化指标显著影响过桥米线的品质。样品2喜好度最高,其直链淀粉含量为22.20%、蛋白质含量为4.51%,酸度为0.015%,脂肪为0.38%,pH值为6.5,支链淀粉含量为37.03%,白度为70.04,水分含量为67.29%。本文可为过桥米线的品质研究与市场生产提供理论参考。

水稻雄性不育系异交性状的相关与通径分析

[目的]对8个水稻雄性不育系的异交性状进行相关及通径分析,为杂交稻高产制种提供依据。[方法]以福恢366为父本进行人工授粉和田间赶粉制种,比较了8个水稻雄性不育系的异交性状及相关农艺性状,并对制种异交结实率(Y)与17个性状(X1~X_(17))进行相关及通径分析。[结果]8个不育系花时动态、开花集中度及柱头活力系数等性状存在明显差异。相关性分析表明,制种异交结实率与柱头双边外露率(X_(7))、柱头总外露率(X_(8))、柱头活力系数(X_(14))、开颖角度(X_(15))及开花集中度(X_(17))均呈显著或极显著相关,其中与开花集中度的相关系数最大,为0.96。通径分析表明,制种异交结实率与粒长(X_(4))、粒宽(X_(5))、柱头双边外露率、柱头总外露率、柱头活力系数及开花集中度密切相关,回归方程为:Y=42.872 4+3.534 8X_(4)+7.095 9X_(5)+0.200 3X_(7)+0.186 3X_(8)+2.002 7X_(14)+0.469 2X_(17)。开花集中度与制种异交结实率的直接通径系数最大,达0.587 3。[结论]在水稻雄性不育系选育及杂交稻种子生产上,应重点关注柱头外露率、柱头活力系数及开花集中度等性状,以提高制种产量。

随机车载下的桥梁车致位移极值预测

为了准确预测随机车辆荷载作用下的桥梁车致位移极值,本文充分考虑过桥车辆的随机性特征,采用蒙特卡罗随机抽样的方法建立随机车流荷载模型;基于经典Rice公式极值预测理论,给出公路桥梁车致位移极值的预测方法。实际工程的应用结果表明:经典Rice公式对桥梁车致位移界限跨阈次数的拟合效果很好,提出的桥梁车致位移极值预测方法有效可靠且在工程实践中应用方便。中小跨径桥梁在随机车载作用下的位移界限跨阈率取决于过桥车辆数量,受过桥车辆间距的影响较小。桥梁车致位移极值随着重现期的增加而增大,梁式桥边梁的车致位移极值和位移首超失效概率大于其他主梁。

紫稻细胞质雄性不育系叶片全蛋白双向电泳分析

通过对几种不育系叶片全蛋白双向电泳图谱分析证明 :紫稻不育系具有不同于野败型、红莲型和马协型不育系的蛋白图谱 ,说明其可能是一种新的细胞质质源。同时 ,紫稻不育系与保持系蛋白图谱之间在三叶期和分蘖期时差异均不明显 ,但各材料本身蛋白图谱在两个不同时期之间差异很大。不育系与保持系图谱表现出的蛋白质(多肽 )的差异 。

水稻远缘杂交后代的耐强光和抗光氧化特性

为探明通过远缘杂交(Oryza sativaAzucena×Oryza rufipogonRamper6)手段获得的水稻高光合后代株系(SHPF6)在生长关键时期的耐强光和抗光氧化能力,本文以生育期一致的推广品种中花10号为对照,进行了光合作用测定和抗光氧化特性的研究。结果表明,强光下SHPF6表现较高的净光合速率Pn,并随着光强进一步增强而有较大的上升,这种高光合优势突出表现于Pn与胞间CO2浓度(Ci)的极显著负相关(r=-0.767,P<0.01),及气孔导度(Gs)、蒸腾速率(Tr)无论光强大小均高于对照;光氧化条件下,中花10号Fo显著升高(P<0.05),Fv/Fm和Fv/Fo均显著降低(P<0.05),而SHPF6各荧光参数在统计上没有较大差异,说明SHPF6具有较强的抗光氧化能力。这些结果意味着,通过远缘杂交手段,不仅可以提高普通栽培品种的光合速率和CO2羧化能力,还能改善水稻的抗光氧化能力。

三交水稻的育种研究 Ⅲ.三交中晚稻主要农艺性状的配合力和遗传力分析

用4个纯合不育系菲A、中9A、金23A和珍汕97A,4个杂合不育系菲A协青早B、中9A协青早B、金23A协青早B和珍汕97A协青早B,3个恢复系752、测647和优米2号,按8×3NCⅡ交配设计,对16个性状的配合力进行分析。结果表明,所有性状的一般配合力和特殊配合力均达到了显著或极显著水平。在播始历期、穗长、千粒重、结实率、有效穗数和剑叶宽等性状上,以加性效应占主导作用;而在株高、单株产量、每穗实粒数、每穗总粒数、着粒密度和剑叶角度等性状上,则以非加性效应为主。杂种的大多数农艺性状受恢复系的影响比不育系大得多,所以三交中、晚稻应重视恢复系的选择。各性状的狭义遗传力由大到小的顺序为播始历期、株高、剑叶宽、结实率、穗长、千粒重、剑叶长、有效穗数、粒长、粒形、每穗实粒数、每穗总粒数、粒宽、单株产量、着粒密度、剑叶角度。

特种稻米中微量元素铁、锌、锰含量的配合力和稳定性分析

以米粒中微量元素铁、锌、锰含量各具差异的７个特种稻品种配制完全双列杂交，利用Ｇｒｉｆｆｉｎｇ方法１模型Ⅰ分析３种微量元素含量的配合力；利用变异系数分析法研究７个亲本在不同地点、不同年份间微量元素含量的稳定性。结果表明，铁、锌、锰３种微量元素的一般配合力（ＧＣＡ）方差和特殊配合力（ＳＣＡ）方差均达极显著水平，其中铁含量的ＳＣＡ方差大于ＧＣＡ方差，锌、锰含量ＧＣＡ方差大于ＳＣＡ方差，说明这３种元素同时受加性和非加性基因作用，铁含量以非加性效应为主，锌和锰含量则以加性效应为主。同一亲本３种元素间ＧＣＡ效应差异较大，同一元素不同亲本间差异亦较大；同一元素不同组合间ＳＣＡ表现较大变幅，并有ＧＣＡ效应高的亲本其杂交组合的ＳＣＡ效应多数表现较高的趋势，但亦有ＧＣＡ低的亲本间杂交出现ＳＣＡ高的组合。变异系数分析结果显示，７个亲本在不同年份、不同地点间，各元素含量的差异较大，表明稻米中铁、锌、锰含量除受遗传控制外，还明显受环境条件的影响，并表现基因型×环境互作。

栽野稻远缘杂交高光效后代及其亲本叶片的气孔特性

为分析远缘杂交后代材料的高光效生理基础 ,测定了从热带地区筛选出的杂交高光效后代材料 SHP1(F2 )、SHP1- 1- 6 (F3 )、SHP1- 2 - 8(F3 )及其亲本 Azucena(O.sativa)与普通野生稻 (O.rufipogon) ,以及 3个对照品种 (O.sativa)的光合速率和气孔特性 ,分析了光合速率与气孔导度和气孔结构的关系。结果表明 3个高光效后代材料的光合速率和气孔密度及气孔乳突数显著高于其亲本及 3个栽培稻。相关分析表明 ,光合速率与气孔导度和气孔密度分别呈极显著、显著正相关 (相关指数分别为 R2 =0 .90 44 * * ,R2 =0 .810 0 * ) ,气孔密度与气孔导度表现出显著正相关 (R2 =0 .86 98* )。因此认为气孔是决定水稻光合速率的重要因子之一 ,通过与野生稻远缘杂交增加气孔密度可提高气孔导度 ,从而可能改善光合效率。

三交水稻的育种研究Ⅱ.三交中晚稻杂种优势的比较研究

用4个纯合不育系菲A、中9A、金2 3A和珍汕97A ,4个杂合不育系菲A 协青早B、中9A 协青早B、金2 3A 协青早B和珍汕97A 协青早B ,3个恢复系75 2、测6 4 7和优米2号,按8×3NCⅡ交配设计配制2 4个组合。比较研究了三交种的杂种优势及株高和抽穗期的变异程度。结果表明,5 8 33%的三交种比相应单交种具增产优势,平均增产6 11%。单株产量最高的为三交组合珍汕97A 协青早B 测6 4 7,其平均优势率为6 0 2 9% ,最优优势率为9 94 % ,株高和抽穗期的变异系数也与相应单交种接近。说明三交中、晚稻具有较强的增产潜力,可筛选出农艺性状整齐度符合生产要求的水稻三交组合。三交种的千粒重优势特别突出,在中、晚稻育种上值得利用。