Analysis of Variations in White-Belly and White-Core Rice Kernels Within a Panicle and the Effect of Panicle Type

This study aims to investigate the variation in occurrence of white-belly rice kernel（WBRK） and white-core rice kernel（WCRK） among different positions within a panicle. Twenty-four M4 mutants involved in four panicle types, namely the compact, intermediate, loose, and chicken foot panicle were used. They derived from a japonica rice cultivar Wuyujing 3. Considerable differences in morphological characters existed among the four types of panicle, especially in panicle length, the secondary branch number and ratio of grain number to total branch length. Marked differences were found in WBRK and WCRK among different positions within a panicle for all types of panicle. In general, grains located on the primary rachis and top rachis branches had higher WBRK and WCRK percentage than those on the secondary rachis and bottom rachis branches. WCRK exhibited larger variation among grain positions than WBRK did. Moreover, there was a significant difference in WCRK/WBRK among grain positions within a panicle, with primary rachis and top rachis branches having higher values than the secondary and bottom rachis. In addition, panicle type showed no significant effect on the pattern of WBRK and WCRK occurrence within a panicle. The results indicated the difference in mechanism of WBRK and WCRK formation in grain position within a panicle, and are valuable for breeding and agronomic practices aimed at lowering chalky grain rate.

A method to measure the rice kernel chalkiness objectively

Rice kernel chalkiness is an impor-tant quality character.Being the un-transparent portions in grain en-dosperm,chalkiness iS always mea-sured by some subjective eye-judgingmethods domestically and interna-tionally.Results measured by suchmethods aye subjective,inaccurate,and unstable.This research is in-

Optical Sum Frequency Generation Spectroscopy of Cracked Non-Glutinous Rice (Oryza sativa L.) Kernels

In order to study the correlation between the cracking of rice (Oryza sativa L.) kernels and the molecular structure of the amylopectin in them, we attempted optical sum frequency generation (SFG) spectroscopy in the C-H stretching vibration region for normal and cracked japonica non-glutinous rice kernels. The samples were Koshihikari and Nipponbare. In Nipponbare, the width of the SFG spectrum peak at 2915 cm- 1 of the cracked rice kernels was broader than that of the normal ones, while for Koshihikari there was no clear difference. The width of the 2915 cm- 1 peak is suggested to originate from the variety of the higher-order structure of the saccharide chains in amylopectin. Although this is a tentative result, this method is shown to have a potential of serving for preventing the cracking of the rice kernels.

Nutritional value of high fiber co-products from the copra,palm kernel,and rice industries in diets fed to pigs

High fiber co-products from the copra and palm kernel industries are by-products of the production of coconut oil and palm kernel oil. The co-products include copra meal, copra expellers, palm kernel meal, and palm kernel expellers. All 4 ingredients are very high in fiber and the energy value is relatively low when fed to pigs. The protein concentration is between 14 and 22 % and the protein has a low biological value and a very high Arg：Lys ratio. Digestibility of most amino acids is less than in soybean meal but close to that in corn. However, the digestibility of Lys is sometimes low due to Maillard reactions that are initiated due to overheating during drying.Copra and palm kernel ingredients contain 0.5 to 0.6 % P. Most of the P in palm kernel meal and palm kernel expellers is bound to phytate, but in copra products less than one third of the P is bound to phytate. The digestibility of P is, therefore, greater in copra meal and copra expellers than in palm kernel ingredients. Inclusion of copra meal should be less than 15 % in diets fed to weanling pigs and less than 25 % in diets for growing-finishing pigs. Palm kernel meal may be included by 15 % in diets for weanling pigs and 25 % in diets for growing and finishing pigs.Rice bran contains the pericarp and aleurone layers of brown rice that is removed before polished rice is produced.Rice bran contains approximately 25 % neutral detergent fiber and 25 to 30 % starch. Rice bran has a greater concentration of P than most other plant ingredients, but 75 to 90 % of the P is bound in phytate. Inclusion of microbial phytase in the diets is, therefore, necessary if rice bran is used. Rice bran may contain 15 to 24 % fat, but it may also have been defatted in which case the fat concentration is less than 5 %. Concentrations of digestible energy（DE） and metabolizable energy（ME） are slightly less in full fat rice bran than in corn, but defatted rice bran contains less than 75 % of the DE and ME in corn. The concentration of crude protein is 15 to 18 % in rice bran and the protein has a high biological value and most amino acids are well digested by pigs. Inclusion of rice bran in diets fed to pigs has yielded variable results and based on current research it is recommended that inclusion levels are less than 25 to 30 % in diets for growing-finishing pigs, and less than 20 % in diets for weanling pigs.However, there is a need for additional research to determine the inclusion rates that may be used for both full fat and defatted rice bran.

Identification of QTL for kernel number-related traits in a rice chromosome segment substitution line and fine mapping of qSP1

A chromosome segment substitution line (CSSL) is a powerful tool for combining quantitative trait locus (QTL) mapping with the pyramiding of desirable alleles. The rice CSSL Z1364 with increased kernel number was identified in a BC3F8 population derived from a cross of Nipponbare as the recipient with Xihui 18 as the donor parent. Z1364 carried three substitution segments distributed on chromosomes 1, 6, and 8. The mean substitution length was 1.19 Mb. Of 17 QTL identified on the substitution segments, qSP1 for spikelets per panicle, qSSD1 for seed-set density, and qNSB1 for number of secondary branches explained respectively 57.34%, 87.7%, and 49.44% of the corresponding phenotypic variance and were all linked to RM6777. Chi-square analysis showed that the increased kernel number in Z1364 was inherited recessively by a single gene. By fine mapping, qSP1 was delimited to a 50-kb region on the short arm of chromosome 1. Based on DNA sequence, a previously uncharacterized rice homolog of Arabidopsis thaliana AT4G32551 was identified as a candidate gene for qSP1 in which mutation increases the number of spikelets and kernels in Z1364. qSP1 was expressed in all tissues, but particularly in 1-cm panicles. The expression levels of OsMADS22, GN1A, and DST were upregulated and those of LAX2, GNP1, and GHD7 were downregulated in Nipponbare. These results provide a foundation for functional research on qSP1.

稻米胚芽酸枣仁乳粉工艺研究

以稻米胚芽粉、全脂奶粉、酸枣仁粉、百合粉为主要原料,采用单因素试验和正交试验,优化稻米胚芽酸枣仁乳粉的生产工艺。结果表明:稻米胚芽酸枣仁乳粉的最佳工艺为全脂奶粉添加量25.0 g、稻米胚芽粉添加量4.0 g、酸枣仁粉添加量0.5 g、百合粉添加量2.0 g、稻米胚芽粉粒径0.050 mm、剪切时间15 min,在此条件下制得的稻米胚芽酸枣仁乳粉风味较好,口感最佳,溶解性好,综合评分为88。

国内各级留胚米产品标准的比较与分析

留胚米是新兴的大米加工产品。与传统大米产品相比,具有营养价值高、加工精度低的特点,符合当前社会流行的全谷物营养消费趋势及适度加工节粮减损的粮食产业政策导向。以我国现行有效的各级留胚米产品标准为研究对象,就产品名称、留胚粒率、加工精度、水分含量及保质期等主要技术指标作了比对分析,开展了关键指标验证试验,指出了当前市场存在的问题,为下一步规范留胚米产品的加工生产、保障提升留胚米产品的营养品质、构建“优质优价”的留胚米流通体制提供有力的参考。

An Exploratory Study on Allelic Diversity for Five Genetic Loci Associated with Floral Organ Development in Rice

Allelic diversity for five genetic loci (DL, FON4, OsMADS24, OsMADS45 and Spw1) associated with floral organ development were investigated among a small heterogeneous rice population which included one wild species (O. rufipogon Griffiths), one indigenous less popular natural floral organ mutant (O. sativa var. indica cv. Jugal), one indigenous normal line (O. sativa var. indica cv. Bhutmoori) and one improved high yielding line (O. sativa var. indica cv. IR 36). Detailed spikelet morphology showed that var. Jugal had variable number (1 - 3) of carpels within a single spikelet which was unique and resulted in variable (1 - 3) number of kernels within a single matured spikelet (grain). The genomic DNA of each investigated line was amplified with primer sequences designed from the selected genetic loci and the derived polymorphism profiles were used for study of allelic diversity for the studied loci. The derived genetic distances among the rice lines were used for dendrogram construction. In constructed dendrogram, the mutant genotype (Jugal) showed highest similarity with the wild rice (O. rufipogon) instead of the rice lines. To verify this finding, the genomic DNA of each studied line was also amplified with four SSR loci, tightly linked to saltol QTL, mapped to rice chromosome 1. The amplified products were screened for polymorphism and another dendrogram was constructed to reveal the genetic distance among the lines for selected salt tolerance linked SSR loci. In SSR derived dendrogram, the wild rice (O. rufipogon) got totally separated from the all three rice genotypes though all the studied four lines showed equal sensitivity for salt sensitivity in a physiological screening experiment. From the combined experiment, it can be concluded that genetic architecture of floral organ development loci in var. Jugal may have some uniqueness which is not present in normal rice but common to O. rufipogon, a species which is regarded as immediate progenitor of present day modern rice (O. sativa). Though this uniqueness was not confirmed by second set genetic loci associated with salt tolerance in rice, the information resulted from this experiment was preliminary and based only on allelic size (molecular weight of amplicon), which should be confirmed through sequence analysis for further analysis.

Performance of Different Cultivars in Direct Seeded Rice (<i>Oryza sativa</i>L.) with Various Seeding Densities

Optimum seeding density is necessary to achieve the production potential of a cultivar in all crops. To investigate the performance of different cultivars in direct seeded rice in response to various seeding densities, a field experiment was conducted at Agronomic Research Area, University of Agriculture, Faisalabad during the kharif 2012. Super basmati (fine rice) and KSK-133 (coarse rice) were sown using seeding densities of 30, 45, 60 and 75 kg&middotha-1. Results indicated that leaf area index and crop growth rate varied among rice cultivars as well as various seeding densities. The growth of rice at seeding density of 75 kg&middotha-1 was higher than rest of treatments. The response of rice yield and its components like number of productive tillers, number of kernels per panicle and 1000-kernal weight differed significantly under the influence of cultivars and various seeding densities. Seeding density of 75 kg&middotha-1 remained superior for both rice cultivars regarding final yield. This treatment furnished kernel yields of 3.83 and 5.49 t&middotha-1 in fine and coarse rice, respectively which were significantly higher than other treatments. However, Kernel quality was improved in terms of lower number of sterile and chalky kernels at lower seeding densities (30 kg&middotha-1). Based on these findings, it is concluded that using seeding density of 75 kg&middotha-1 for direct seeded fine and coarse rice cultivars is beneficial in terms of better growth and higher yield but kernel quality is reduced by increasing the seeding density.

水稻qGL3.4调控籽粒大小与株型

籽粒大小与株型对水稻产量具有重要影响,因此其相关基因克隆与功能研究对培育高产水稻具有重大的意义。本研究从以短舌野生稻为供体、华粳籼74 (HJX74)为受体的染色体单片段代换系(SSSLs)中鉴定到一个新的调控籽粒大小与株型的QTL位点qGL3.4。与对照HJX74相比,近等基因系NIL-qGL3.4的粒长、粒宽、千粒重、穗长、穗粒数、一次枝梗数、单株产量与株高显著增加,而NIL-qGL3.4的分蘖数和二级枝梗数与HJX74对应值无显著差异。通过图位克隆,将qGL3.4定位在第3号染色体239.18 kb区间内。细胞学分析表明,NIL-qGL3.4通过调节颖壳细胞的生长进而调控籽粒的大小。分子机理研究表明,qGL3.4可能通过调控籽粒大小相关基因EXPANSINs、GS3、GL3.1、PGL1、GL7、OsSPL13和GS5的表达进而调控籽粒大小。本研究可能为高产与理想株型的水稻培育提供新的靶标位点。

2种电饭煲烹饪米饭质构测试方法比较研究

目的基于物性分析仪比较分析测试电饭煲烹饪米饭质构特性的2种方法.方法采用米粒法和米饼法分别进行测试参数优化,并基于最优参数下进行方法的对比研究,以变异系数评价测试方法的稳定性、重复性.结果米饼法测试的质构特性变异系数小、数据稳定性高、重复性好,且与适口性呈显著相关性,能较好地反映米饭适口性.米饼的制样选择90 mm规格测试皿,米饭量选择87 g,物性分析仪探头选用圆柱形P36R型,最优参数为:75%压缩比、0.5 mm/s测试速度.结论米饼法测试米饭质构能更好地反映米饭的软硬度、黏性以及弹性,且数据离散程度小、稳定性高.

网络时代农产品质量安全事件风险扩散的路径研究——以镉大米事件为例

以镉大米事件为例,媒介报道数据为基础,综合应用核密度估计法、最邻近指数、热点分析和变异系数等方法以探索性揭示网络时代镉大米事件风险扩散的时间演化过程及空间路径。结果表明:镉大米事件风险扩散时间演化呈现“高—低—高”的V字态势在年际间波动显著,其变动可对应为爆发期、回落期、反弹期;事件风险的空间路径则表现为“单核心—发散式”特征在域间传播。

垩白米粒的计算机图像识别

自行开发研制了计算机图像处理系统 ,用于优质稻谷国家标准 GB/T17891- 1999中质量指标垩白度及垩白粒率的检测。利用该系统对 6种粳米和 2种籼米进行测定 ,结果表明 ,该方法具有客观性、准确性、快速性和可重复性等特点 。

稻米垩白的形成及其调控

就稻米垩白形成的物理和化学特性、细胞学特点、垩白形成与“源—库”关系以及影响垩白形成的诸多因素进行了综述 ,指出了目前相关研究领域中存在的问题和今后的发展趋势 ,提出了将现代试验设计和电子计算机技术引入垩白形成机理的研究以全面定量地考察垩白形成及其影响因素之间的关系 ,综合遗传和非遗传措施 。

蒸煮过程中稻米水分状态的质子核磁共振谱测定

对 3种稻米蒸煮过程中水分的状态进行了 1 H- NMR测定。结果表明 ,不同品种的原料稻米具有相近的弛豫特征。但在蒸煮过程中 ,纵弛豫时间会因品种的不同而呈现出显著的差异。分析结果认为 ,稻米中水分的存在状态有自由水、构造水和结合水等 3种形式。蒸煮过程中各种稻米水分状态的差异与谷粒中有机物的理化特性密切相关 ,并可能是导致米饭具有不同食味特性的重要原因。

基于稀疏表示的大米品种识别

为了实现机器视觉准确判别大米品种,提出了一种基于稀疏表示的大米品种识别方法。以长江米、圆江米、粳米、泰国香米、红香米和黑米等6种大米籽粒图像作为研究对象,采用颜色和形态结构参数表示单个籽粒。每种大米随机选取50粒作为训练样本,200粒作为测试样本。所有训练样本组成稀疏表示方法的数据词典,对每一个测试样本,计算其在数据词典上的投影,将具有最小投影误差的类作为测试样本所属的品种。最后将提出的方法与BP网络和SVM的识别结果做了对比和分析。试验结果表明,提出的方法对于6个大米品种的综合识别准确率为99.6%,获得了最好的分类效果。为大米品种的识别提供了一种新的有效方案。

一种基于主动轮廓模型的连接米粒图像分割算法

针对图像中连接米粒分割困难的问题,提出了一种基于主动轮廓模型的分割算法。首先,对籽粒二值图像的欧氏距离变换进行局部极小值检测,并通过形态学膨胀算子合并局部极小值点,在每个籽粒内部只产生一个区域。其次,以这些区域的边界作为初始曲线,在主动轮廓模型的指导下,曲线向籽粒的边界演化,最终将图像中各个米粒分割。试验结果表明,对圆江米、粳米、长江米和黑米4个品种的米粒,基于主动轮廓模型的连接米粒图像分割算法的分割正确率分别达到93.4%、92.4%、88.0%和90.4%,综合准确率为91.05%,比基于分水岭的方法提高了26.7%。因此,基于主动轮廓模型的算法为分割连接米粒图像提供了一种有效途径。

早籼稻米垩白形成与稻株源-库特性关系的研究

以垩白度差异较大的 3个早籼稻品种为材料 ,先后分 3期播种 ,应用14 C示踪技术研究了籽粒灌浆期剑叶净同化速率、籽粒库活力及相应的源 /库比与稻米垩白形成的关系。结果表明 ,稻株源 -库特性与稻米垩白度之间表现出显著的相关性。低垩白品种剑叶净同化速率、籽粒库活力和源 /库比均显著高于高垩白品种。稻株库的容量大、库的活力低而源叶同化物又供应不足 ,势必形成垩白。因此 ,保证源的供给充足、适当的库容 (库的大小 ) ,较大的源 库比和强大的库活力对减少稻米垩白极为重要。研究还发现 ,垩白度高的水稻品种 ,其剑叶中同化物的输出百分率相应较低 ,推测其源叶中同化物的输出或韧皮部装载存在障碍。

贮藏对籼稻米蛋白质营养品质的影响

研究测定了华南地区有代表性的１１个早籼优质品种稻米于常温下贮藏１ａ前后蛋白质含量和氨基酸组成用ＦＡＯ／ＷＨＯ必需氨基酸的评分模式及鸡蛋白模式作比较，计算了１１个籼稻米８种必需氨基酸的化学分，对稻米蛋白质质量进行了评价结果表明：稻米经过常温贮藏１ａ后，其蛋白质含量及氨基酸组成和含量比较稳定，稻米蛋白营养品质基本不受贮藏时间的影响；１１个稻米品种的蛋白质质量分数变幅介于８８０％～１３１０％，平均值为１０２３％，变异系数为１０８０％，品种间差异较大；品种间８种必需氨基酸的含量存在明显差异，分析的品种中８种必需氨基酸的绝对含量的变幅和变异系数均大于其相对含量的变幅和变异系数；稻米蛋白质含量也存在明显的品种间差异，但存在必需氨基酸总量随蛋白质含量提高而减少的趋势。

基于计算机视觉的大米粒形识别方法

提出了利用计算机视觉系统代替人眼识别整粒大米和碎大米粒形的方法。设计了一套基于计算机视觉技术的大米粒形识别装置,采用灰度变换、阈值分割、平滑处理等图像处理方法获取大米的粒形图像,然后根据大米的粒形特点提取了米粒的面积、周长、长、宽等16个特征参数,采用主成分分析方法对提取的特征参数进行处理,以前三个主成分综合所有粒形特征参数,作为BP神经网络的输入特征值对网络进行训练和大米粒形识别。试验结果表明:该方法对整粒米识别的准确率为98.67%;对碎米识别的准确率为92.09%。