Studies on the amylose content and gelatinisation temperature in certain local cultivars and induced grain shape mutants in rice

Summary Ninety local cultivars and 124 induced grain shape mutants were screened for their amylose content and gelatinisation temperature as indexed by the alkali disintegration patterns. The amylose content was high in most of the local cultivars and ranged from 19.2 to 32.0% and from 12.3 to 33.2% in the mutants. Wide variation was also observed for the alkali disintegration values and most of the varieties had low alkali values. A positive but low correlation between alkali values and amylose content and a negative correlation between alkali values and protein content was observed. The preliminary studies suggest that the amylose content at different milling levels increased with an increase in the level of milling. Some of the local cultivars and induced mutants were found to be superior with high amylose and high gelatinisation temperature and could be utilized in breeding programmes directed towards improving the cooking quality of high yielding varieties.     

辽宁滨海稻区水稻新品系品质性状分析

为了研究辽宁滨海稻区水稻新品系品质特性,以期为优质水稻新品种选育提供参考。以30份粳稻新品系为试材,对新品系稻米品质性状进行评价及相关分析。结果表明：新品系碾磨品质中的糙米率和整精米率的平均值分别达到国家2级优质米标准和国家1级优质米标准,垩白粒率和垩白度变异系数较大,分别为50.44%和52.34%;品质性状间存在显著或极显著的相关性,胶稠度和碱消值与食味值呈显著正相关(r=0.660,r=0.586),直链淀粉含量与食味值呈极显著负相关(r=-0.849)。因此,在今后的选育优质水稻新品种过程中,应注意降低垩白率、垩白度和适当降低直链淀粉含量,并兼顾其他品系的改良。     

北方国家水稻区域试验近15年参试品种分析

通过对2001-2015年北方稻区国家水稻区域试验数据分析,发现北方稻区参试品种数量稳中有增,区域试验规模不断扩大;水稻品种产量水平有了明显的提高,单产从2001年的9.08t/hm ²增加到2015年的10.11t/hm ²,增加了11.3%。通过分析产量构成因素发现,北方稻区必需有一定数量的有效穗数做基础,同时协调好穗粒数、结实率和千粒重的关系,才能获得较高的产量。北方水稻区域试验品种优质率平均在60%以上,品质总体较好;早熟中早粳和中熟中早粳品质优于黄淮粳稻组和晚熟中早粳。从主要米质指标上看,整精米率和直链淀粉含量相对较好,而垩白粒率和垩白度相对较差,是影响北方稻米品质的主要因素。北方稻区平均每年有32.7%的品种达中抗稻瘟病及以上水平,同时每年约有40%的品种因稻瘟病抗性不达标被淘汰;而且年度间稻瘟病抗性品种比例波动较大,说明北方水稻品种稻瘟病抗性不强、不稳定,稻瘟病抗性育种研究还需进一步提高和加强。     

水稻生育期对籽粒产量及品质的影响

明确水稻生育期与产量、品质的关系,对水稻高产优质育种和合理栽培措施的制定,具有重要的意义。本文以晚粳宁111和春江302经遮光(短日照)处理后获得的不同生育期水稻植株为材料,分析其产量和米质指标。结果表明,生育期152 d以上时,对产量无显著影响,而生育期短于152 d时,产量与生育期间呈极显著正相关;成熟期群体干物质积累量随生育期变化的趋势与产量表现基本一致。不同稻米的长度、宽度、蛋白质含量以及淀粉消减值,均以中等偏短生育期(131~132 d)最小,大于或小于131~132 d,均会使上述指标值增加;两品种直链淀粉含量亦有相似的趋势,只是其最低值分别对应132和137 d的生育期;各处理稻米淀粉的崩解值变化与消减值趋势相反。对垩白粒率、垩白度及糊化温度,各处理均呈随生育期延长而降低的趋势;生育期变化对碾米品质影响总体上较小。     

寒地早粳品种对稻米品质的影响

以近几年主栽的水稻品种为试材,采取相关统计分析和对比试验等方法,研究了水稻品种对早粳稻米品质的影响,旨在为寒地稻作区优质米品种的选育和高产栽培提供理论依据和技术支持。研究取得如下主要结果：（1）不同熟期碾米品质的3项指标中,糙米率的平均值分别为83.1%、82.9%、83.1%、83.0%;精米率的平均值分别为71.9%、71.9%、72.0%、73.0%。不同品种的糙米率,不同熟期间差异很小,晚熟品种的精米率略高于早熟和中熟品种,品种间表现有差异。不同熟期的整精米率的平均值分别为61.7%、61.7%、66.5%、67.2%,晚熟品种比早熟和中熟品种高,品种间差异较大。早熟和中熟品种的整精米率变异系数较晚熟品种增加1.2个百分点,说明品种间差异较大。稻米垩白米率与胶稠度（0.0566）呈正相关,这一点与（李雅娟,1995）的研究结果一致。垩白米率与精米率（-0.4827）呈显著负相关,因此,在育种上筛选垩白米率低的种质资源是关键。（2）直链淀粉含量是影响稻米食味品质的最重要指标之一,很多研究认为,直链淀粉含量偏高影响稻米食味品质（佐佐木忠雄,等．1982）。关于直链淀粉含量姬田正美（1996）研究认为,直链淀粉含量越高,稻米食味越差。本研究结果直链淀粉含量一般在16.67%~22.40%,平均含量为18.8%,品种间差异较大。直链淀粉含量与蛋白质含量（-0.8207）呈极显著负相关。     

大麦籽粒淀粉和β-葡聚糖积累特性研究

为研究大麦籽粒支链淀粉、直链淀粉和β-葡聚糖积累特性,及淀粉各组分与β-葡聚糖的关系,以2个皮大麦、1个裸大麦和1个糯裸大麦为试验材料,测定花后7、14、21、28d淀粉各组分及β-葡聚糖含量。结果表明,甘啤6号淀粉各组分含量随灌浆推进均逐渐升高,在成熟期达到最大值;甘垦啤7号和甘垦6号均呈先升高后降低趋势,在花后21d有1个峰值。糯大麦C 2-1直链淀粉含量显著低于非糯大麦;支链淀粉含量显著高于非糯大麦,整个灌浆期呈先升高后降低趋势。β-葡聚糖含量均随灌浆时间延长逐渐升高,成熟期含量最高;整个灌浆期糯大麦C 2-1含量显著高于非糯大麦。相关分析表明,直链淀粉/支链淀粉比值与β-葡聚糖含量呈极显著负相关,可以将直链淀粉/支链淀粉比值作为高β-葡聚糖品种选育的一个指标。Logistic方程拟合发现,直链淀粉、β-葡聚糖最终积累量与积累起势与有效积累时间有关,支链淀粉最终积累量取决于最高积累速率和平均积累速率。     

嘉兴水稻海南育种的品质差异及育种策略

经过对嘉兴香米、苏95-22等7个非糯水稻品种(系)海南和嘉兴不同育种条件下成熟稻米品质分析,发现与稻米商品品质密切相关的同一品种的直链淀粉含量、外观品质、食味等性状嘉兴和海南截然不同。分析其原因是抽穗后温度条件不同所致,即灌浆时期气温升高或降低,其直链淀粉含量、外观、食味等性状也随之发生变化。无论是早籼稻,还是晚粳稻,这种变化趋势完全一致。根据这一情况,异地育种或不同季节选育品种时,应根据温度条件不同,建立相应的检测指标,以提高针对性、减少品种选育的盲目性。其次,对优质水稻生产来说,改善栽培条件便可进一步提高稻米的食用品质。     

水稻低直链淀粉资源筛选

为了在水稻外观品质改良的同时提高食味品质,通过对引自IRRI及中国水稻种质资源库的1000多份材料测定直链淀粉含量,并对IRRI资源测定外观品质.研究发现:目前水稻优良食味品种多数外观品质差,且"软米"标准欠缺.水稻直链淀粉含量分布十分宽,其中软米范围品种数量少,糯米品种较软米品种多,且分为优质糯稻与劣质糯稻两类.其他...     

施氮量对优质常规籼稻稻米品质的影响

为探讨施氮量对优质常规籼稻稻米品质的影响，以桂香18、桂育12、桂育9号、桂育11号、桂育18和桂育8号为材料，在4种不同施氮量下分析稻米品质指标。结果表明，糙米率和整精米率随施氮量的增加呈先升后降的趋势，供试品种在施氮150.0kg/hm²时其值较高；垩白粒率和垩白度随施氮量的增加而降低，供试品种在施氮150.0或187.5kg/hm²时其值较低，且在施氮150.0和187.5kg/hm²时，粒长和长宽比差异不显著；随施氮量的增加，直链淀粉含量呈上升趋势，蛋白质含量显著升高，供试品种在施氮150kg/hm²时直链淀粉含量均达到优质一等。综上，在本试验条件下，150kg/hm²是实现供试品种稻米品质较优的最适施氮量。     

寒地粳稻碾磨品质和食味品质相关性状的综合分析

为阐明寒地粳稻碾磨品质和食味品质性状间的相互关系，以337份高世代纯合品系材料为对象，对其11个品质指标进行相关、主成分和聚类分析，构建准确可行的稻米品质评价回归方程。结果表明，糙米率、精米率和整精米率间呈显著正相关，食味评分与蛋白质和直链淀粉含量均存在相关关系。在主成分分析中，累计方差贡献率80%以上的主成分共4个，综合得分排名前5的水稻品系分别为J139、J201、J141、J204和J138。以食味评分为因变量，糙米率、精米率、蛋白质含量、含水量和直链淀粉含量为自变量得到回归方程。这些研究手段及回归方程可用于快速、准确分析新品系稻米品质，比较品系间差异。     

Morphological and molecular diversity of Nordic oat through one hundred years of breeding

Summary Genetic diversity in microsatellites and development of agronomical characters in Nordic oat cultivars (Avena sativa) from the 20th century, ranging from landraces to new cultivars, were studied. A clear development in agronomical characters has taken place in this period: Straw length has been reduced, harvest index has increased and heading date has declined. The persistent oat breeding effort in the northern part of the region was indicated by the data, since cultivars from this region showed higher harvest index. Also adaptation to shorter summers was apparent in cultivars from the most northern part of the area. When comparing cultivars released after 1940 to the landraces, the loss of diversity revealed for the agronomical characters was also indicated by the molecular data. This indicates that a more general loss of diversity has taken place in the period, possibly due to random factors during the breeding process (bottleneck effect). The reduction in diversity revealed by recent cultivars at an agronomical as well as a molecular level emphasises the importance of implementing a conservation strategy for older material in order to secure genetic diversity for future oat breeding efforts.     

辽宁省不同熟期水稻品质性状分析

对辽宁省不同熟期水稻品种品质性状进行综合分析,为水稻优质育种和栽培提供参考。以辽宁省中早熟、中熟、中晚熟和晚熟4个熟期65个品种（系）为试验材料,分析辽宁省不同熟期水稻品种（系）品质性状差异及其相关关系。结果表明,垩白粒率、垩白度、透明度的变异系数较大,不同熟期间表现基本一致。4个熟期中中早熟品种（系）的品质性状整体较好,只有垩白度的优质米达标率较低,说明垩白性状是今后水稻品质改良的重点。相关分析表明,垩白粒率、垩白度均与直链淀粉含量呈极显著正相关,与胶稠度呈显著负相关,糙米率与精米率、整精米率、胶稠度呈极显著正相关。辽宁省水稻优质育种可通过合理调整直链淀粉含量,降低垩白粒率和垩白度,提高整精米率,实现品质的整体改善。     

四川不同生态区高产栽培条件下的杂交籼稻的稻米品质

郫县、汉源、射洪、邻水是四川具代表性的4个生态区,郫县位于成都平原区,土壤肥沃但受弱光限制;汉源位于攀西高海拔地区,温光充足;射洪位于川中丘陵区,受地形制约而气温日差较小;邻水则位于川东丘陵区,水资源缺乏且受干旱等灾害制约。本文以位于这4个典型生态区实施的水稻高产示范片为研究对象,分别对4个生态区及各生态区不同栽培方式、不同高产水平的杂交籼稻稻米碾米品质、外观品质、蛋白质含量、直链淀粉含量及淀粉RVA谱特征值进行比较研究。结果表明:(1)生态条件与稻米品质有密切关系,受气温和土壤肥力影响较大,郫县的稻米品质最优,邻水相对较劣;齐穗前后气温略高及较高的土壤全氮、全钾、速效磷含量有利于高碾米品质的形成;土壤全磷含量的降低可显著增加米粒长宽比;灌浆成熟期的高温会增加稻米的垩白粒率和垩白度,而土壤速效磷含量高则有利于降低垩白粒率和垩白度;灌浆结实期的高温也会降低稻米蛋白质含量;直链淀粉含量随土壤有机质含量的升高而升高;峰值黏度与土壤全钾含量显著负相关,崩解值与土壤全钾、速效磷显著负相关,还与齐穗前8~21 d的日最高气温显著正相关,回复值、峰值时间与齐穗前14~21 d日最高气温、抽穗至成熟期日最高气温呈显著或极显著负相关,与土壤碱解氮呈显著正相关。(2)各栽培方式间,机直播的碾米品质较优,优化定抛的直链淀粉含量较高,而机插的峰值黏度、崩解值较高,消减值较低,蒸煮食味品质较好。(3)高产及超高产田块的碾米品质整体较优,而外观品质和蒸煮食味品质相对较差。本研究可为四川杂交中籼稻高产优质栽培技术提供理论参考。     

不同春谷品种支链淀粉含量与营养品质指标及农艺性状的相关性分析

通过田间试验与品质检测,分析了4个不同春谷品种的支链淀粉含量与营养品质指标及农艺性状的内在联系,旨在为优质春谷品种选育提供理论依据。结果表明,各品种的支链淀粉含量存在显著差异;支链淀粉含量与灰分显著正相关,与粗蛋白及直链淀粉含量显著负相关;与刚毛长度极显著正相关,与穗粗和出谷率显著负相关。因此谷子品种选育中,可将不同品系的营养品质指标与农艺性状相结合,提高育种的针对性和效率。     

稻米主要品质性状的相关及主成分分析

为了提高水稻新品种（系）品质性状的选择效率,为水稻品质育种提供理论依据,以22个天津市部分新育成水稻品系为材料,分析其稻米理化特性、淀粉RVA谱特征值、食味值和米饭理化指标之间的关系。结果表明,所测定的13项品质指标在供试品系间均存在着极显著差异;在稻米理化特性中,直链淀粉含量的变异系数最小,蛋白质含量的变异系数最大,在稻米淀粉谱特性中,最高粘度、崩解值、消碱值的品系间变异系数较大。稻米蒸煮食味特性间相关分析的结果表明,食味值与直链淀粉含量和消碱值呈极显著负相关,r=-0.630**和r=-0.736**,与最高粘度和崩解值呈极显著正相关,r=0.695**和r=0.618**。在主成分分析中,被入选的4个主成分的贡献率达82.39%,其中第一主成分因子的贡献最大,达到了44.21%,在第一主成分中,因子负荷量比较大的品质特性有消碱值、直链淀粉含量。利用主成分分析法对22个水稻品系的主要品质性状进行综合评价,在水稻品质食味育种改良过程中,第一、四主成分适当减小,第二、四主成分适当增大有利于水稻的食味品质改良。     

河南沿黄稻区直播稻与常规优质稻稻米品质比较分析

河南沿黄稻区是我国优质粳米生产基地,随着水稻简化耕作栽培方式的发展,直播稻因其简单易行的优点而具有广阔的推广前景。[目的]为研究沿黄稻区直播稻稻米品质与常规插秧稻米品质的差异,[方法]本研究选取6个直播水稻品种和8个插秧水稻品种以及7种优质商品稻米,对其加工品质、外观品质、食味品质以及营养品质性状进行系统比较。[结果]结果表明：整体上,直播稻的精米率高于插秧稻,垩白粒率和垩白度、直链淀粉含量、以及食味值低于插秧稻,高于商品稻米;蛋白质含量高于插秧稻,低于商品稻米;除此之外,相对于插秧稻和商品稻米,直播稻品种的崩解值最大,消减值最小;缬氨酸和胱氨酸含量最高,蛋氨酸含量最低,其余氨基酸含量均低于插秧稻品质,高于商品稻米。[结论]综合所有品质性状指标发现,在选取的6个直播稻品种中,新稻568、郑稻201和新稻567在河南沿黄地区直播条件下的稻米加工品质、外观品质、食味品质以及营养品质都与常规栽培的优质稻米相当,因此可以通过品种选择在保障产量与品质的前提下通过直播简化水稻栽培过程。     

浙江省早籼稻近期区试品种（系）蒸煮品质研究

对水稻区试中多品种(系)、多年、非平衡、无重复分析值的蒸煮品质性状数据,用作者提出的统计方法作了分析。分析结果表明,“八五”期间参试的早籼稻品种(系)蒸煮品质较“七五”参试品种有所改善,高直链淀粉含量的参试品种极显著减少,低直链淀粉含量的参试品种极显著增加;软胶稠度的品种极显著增加,硬胶稠度的品种极显著减少。但多数参试品种胶稠度仍偏硬,综合蒸煮品质不佳。各蒸煮品质性状均以品种效应为主,其次是品种×年份互作效应。蒸煮品质性状的提高,首先应注意品种(系)的主效。各蒸煮品质间有极显著的相关关系,其中直链淀粉与胶稠度的负相关最明显,其次为直链淀粉与糊化温度的负相关。为克服性状相关引起的早籼稻优质育种的难度,应抓好直链淀粉与胶稠度这一主要矛盾并应广泛筛选育种种质资源。     

Variation of <Emphasis Type="Italic">Wx</Emphasis> microsatellite allele,waxy allele distribution and differentiation of chloroplast DNA in a collection of Thai rice (<Emphasis Type="Italic">Oryza sativa</Emphasis> L.)

Eighty-two varieties of rice from different regions in Thailand were selected to explore the Waxy (Wx)gene diversity and indica-japonica differentiation of chloroplast DNA. A comparison of the 5 splice site in the first intron was made between glutinous and nonglutinous rice. It revealed that non-glutinous with low-amylose content and glutinous rice were characterized as the Wx^b allele based on the G-to-T base substitution, whereas non-glutinous rice with intermediate and high amylose carried the Wx^a allele. Four Wx microsatellite alleles, (CT)_n repeat, (n = 16,17,18 and 19) were found in glutinous rice. In contrast, non-glutinous rice showed five Wx microsatellite alleles (n = 11, 16, 17, 18 and 19). The (CT)₁₇ allele was prominent allele in Thai population, while the (CT)₁₁ allele was found only in intermediate and high amylose rice varieties from southern Thailand. Almost all of upland rice grown by various ethnic groups in northern Thailand were characterized as japonica type based on their having the PstI-12 fragment in their cpDNA, whereas most of rainfed lowland varieties from other regions of Thailand were indica. This exploration of DNA-based genetic markers is important, as it enhances our ability to describe and manipulate sources of genetic variation for rice breeding programs.     

Specific adaptation of barley varieties in different locations in Ethiopia

Barley is one of the most important cereal crops grown for the livelihoods of the poor farmers of Tigray region in northern Ethiopia. As many low input and marginal environments it has benefited less from the yield increases achieved by modern breeding. This has been largely attributed due to genotype × environment intraction (GEI). To investigate the causes of GEI, ten barley varieties including local checks (two farmers developed varieties, four modern varieties and three rare local varieties) were tested over 21 environments. Participatory methods were applied to sample an adequate number of environments spanning the regional diversity. The yielding ability and stability of the varieties was graphically depicted by GGE and PLSR biplot. There were two major groups of environments, the central and northern highlands, the latter with less rainfall and poorer soils. Rainfall per month and total nitrogen level were the environmental variables that differentiated these two groups. In Tigray, rainfall in June and July were negatively correlated with yield, reflecting waterlogging problems. The different varieties were either specifically or widely adapted across the two environments. The variety ‘Himblil’, originating in Tigray, was the highest yielding and also most stable in the region of origin. However, it was inferior to improved varieties (Shege and Dimtu) at high yield levels. The association of earliness with grain yield indicates that the trait can be effectively manipulated within the existing materials. We recommend breeding for drought/water logging resistance based on selection in the target environment as the best strategy to provide stable and high yielding varieties for Tigray.     

不同栽培条件下水稻分蘖角度动态变化分析

110161沈阳市东陵路120号沈阳农业大学水稻研究所