湖南省审定的金优系列组合品质性状分析

对1994～2011年湖南省通过省级审定的41个金优组合品质性状进行分析。结果表明，金优系列品种中，早籼组合和晚籼组合品质性状达到国标优一级的达标率较高，表现出晚籼〉中籼〉早籼的趋势；要选育出垩白粒率较低的金优系列组合需选用无垩白恢复系资源进行配组。     

四川省审定的川香29A所配中籼迟熟杂交稻组合品质性状分析

对通过四川省审定的13个川香29A所配三系杂交稻中籼迟熟组合的品质性状进行了分析,并研究了各品质性状间的相关关系。结果表明,13个组合的整精米率平均为58.5%,其中有12个组合达到国颁优质稻谷3级标准以上;长宽比平均为2.8,有5个组合达到国颁优质稻谷3级标准以上;垩白粒率平均为38.2%,有7个组合达到国颁优质稻谷3级标准以上;垩白度平均为7.6%,有6个组合达到国颁优质稻谷3级标准以上;胶稠度平均为63mm,有11个组合达到国颁优质稻谷3级标准以上;直链淀粉含量平均为22.4%,有9个组合达到国颁优质稻谷3级标准以上。在13个组合中只有3个组合的综合米质指标达国颁优质稻谷3级标准,制约综合米质达标的主要因子是长宽比、垩白度和垩白粒率。在各项品质指标中,长宽比与垩白粒率、垩白度呈极显著负相关;垩白粒率与垩白度呈极显著正相关;整精米率与垩白粒率呈显著负相关;直链淀粉含量与垩白粒率、垩白度呈显著正相关。因此,要进一步提升川香29A所配组合的稻米品质,应注重选用粒型细长、垩白粒率低和垩白度小的恢复系来进行配组。     

四川省“十一五”审定的宜香系列杂交稻组合品质性状分析

对“十一五”通过四川省审定的11个宜香系列三系杂交稻组合的品质性状进行了分析,并研究了品质性状间的相关关系。结果表明,这11个组合的整精米率平均为58．91％,有9个组合达到国颁优质稻谷1级标准;长宽比平均为2．98,有9个组合达到国颁优质稻谷1级标准;垩白米率平均为23．84％,有2个组合达到国颁优质稻谷1级标准;垩自度平均为4．68％,有1个组合达到国颁优质稻谷1级标准;胶稠度平均为67．7mm,有5个组合达到国颁优质稻谷1级标准;直链淀粉含量平均为17．08％,有4个组合达到国颁优质稻谷1级标准。在11个组合中有4个组合品质达国颁优质稻谷三级标准,有1个组合达国颁优质稻谷二级标准。在各项品质指标中,整精米率与垩自度呈显著负相关,与胶稠度呈显著正相关,与直链淀粉含量呈极显著负相关;长宽比与垩白度呈显著负相关,与直链淀粉含量呈显著负相关;垩白米率与垩白度呈极显著正相关,与胶稠度呈显著正相关,与直链淀粉含量呈显著正相关;垩白度与与胶稠度呈显著正相关;胶绸度与直链淀粉含量呈极显著负相关。因此,如要进一步提升宜香1A所配组合的稻米品质,应注重选用直链淀份含量略高、垩白无或少、淀粉粒充实紧密、容重大的恢复系。     

强化栽培条件下施肥对杂交水稻主要米质性状的影响

以优质杂交水稻组合D优3232为材料,应用四元二次正交回归旋转组合设计的方法,研究了强化栽培条件下不同氮肥、磷肥、钾肥和硅肥用量配比对主要稻米品质性状直链淀粉含量、垩白粒率和整精米率的影响,建立了主要米质性状与4种肥料用量的回归模型。结果表明,在本试验条件下,磷肥用量是影响直链淀粉含量、垩白粒率、整精米率的主要因素,氮肥与硅肥对直链淀粉含量、垩白粒率以及磷肥与硅肥对垩白粒率均具有显著的互作效应。最佳氮、磷、钾、硅肥组合方案为：尿素171.60-195.90kg/hm^2、过磷酸钙283.35-393.30kg/hm^2、氯化钾102.30-122.70kg/hm^2、硅肥138.30-158.33kg/hm^2;按此施肥方案,在强化栽培条件下,D优3232的主要稻米品质性状可达到国标优质稻谷质量标准。     

不同粒型中籼杂交稻组合稻米品质及相关性分析

通过米粒粒型分类,对2013-2014年通过四川省审定的36个中籼杂交水稻组合的主要品质性状进行了分析,并研究了品质性状指标间的相关关系。结果表明,36个组合中只有2个组合的稻米品质指标全部达国颁优质稻谷标准3级以上,这2个组合的米粒长宽比都在2.9以上;在单个品质性状指标中,这些组合优质达标率(达到国颁优质稻谷标准3级以上)最高的是糙米率,其次是胶稠度,第三是整精米率,达标率较低的是垩白粒率和垩白度。长米粒型组合垩白粒率和垩白度优质达标率均为16.67%,中米粒型组合分别为0和14.29%,短米粒型组合分别为10.00%和0。垩白粒率和垩白度是中籼杂交稻组合稻米品质提升的主要障碍因子。品质性状相关分析结果:垩白粒率和垩白度与米粒长宽比呈极显著负相关,与直链淀粉含量呈极显著正相关;在长米粒型组合中,垩白粒率、垩白度与直链淀粉含量显著或极显著正相关;在中米粒型组合中,垩白粒率、垩白度与米粒长宽比显著或极显著负相关,与直链淀粉含量极显著正相关;在短米粒型组合中,垩白粒率和垩白度与其他主要品质性状相关性均不显著。建议在遗传改良中籼杂交稻垩白粒率和垩白度时可以从粒型着手,选择米粒粒型偏长、容重大、无裂纹、近圆柱形的材料和组合。     

杂交水稻保持系垩白粒率遗传研究

对垩白率不同的5个保持系正反交形成的10对F1、 F′1垩白粒率进行测定和分析,结果发现,垩白粒率在遗传中受到主效基因控制,垩白粒率高对垩白粒率低表现显性或部分显性.对于两个亲本而言,其正交组合的垩白粒率与反交组合垩白粒率有明显差异,以低垩白粒率亲本作母本、高垩白粒率亲本作父本配制的F1 组合的垩白粒率要低于其反交组合米粒的垩白粒率.因此,在优质杂交稻育种中,宜选用垩白粒率低的亲本为母本进行杂交或配组.     

高整精米率杂交水稻新组合旌3优177

旌3优177是四川省农业科学院水稻高粱研究所用自育不育系旌3A与四川省农业科学院作物所育成的恢复系成恢177配组育成的中籼迟熟杂交水稻新组合。该组合不仅高产稳产,并且具有高整精米率、低垩白米率及低垩白度等特点,2015年通过四川省农作物品种审定委员会审定(川审稻2015009)。     

水稻不育系东方龙A的选育及繁育制种技术

东方龙A的选育是针对目前华南地区应用较广的博A、博IIA及秋A、美A等配组的感光组合所存在的一些缺点，如博优组合粒重较轻，一般千粒重都在23g左右，米质较难达到国际优质标准；博A、秋A种子颖壳开裂率在30％-40％左右，开裂度较大，为30～400，且抗性一般，667m^2产量很难超过550～650kg；博IIA配组的组合，种子千粒重有所提高。其后代千粒重也可超过25g，解决了种子开裂的问题，但米质下降严重，特别是长宽比在2.5以下，垩白率、垩白度较高，分别为50％、5％以上；而秋A、美A所配组合米质优，     

优质籼稻不育系粤丰A在改良三系杂交稻品质中的作用

粤丰A是以协青早B与IR58025B杂交,并与珍汕97A测交,经连续回交后育成的国内第1个无垩白、外观透明,软性、浓香型优质籼稻不育系。以该不育系配组育成的丰优系列新组合(其中丰优128和丰优丝苗、丰优香占和丰优559均已分别通过广东和江苏省品种审定)。表现粒形细长,垩白米率和垩白度明显降低,具有低至中等直链淀粉含量和软胶稠度,有香味,食味优。此外,丰优系列组合产量相当于或显著高于同类型对照,生育期适中。因此,该不育系可用于改善杂交稻米的外观品质和蒸煮食味品质,在三系杂交稻育种和生产中具有广阔的利用前景。     

籼型杂交水稻组合加工与外观品质的相关性分析

对2012年四川省水稻区试的127个籼型杂交稻组合的加工和外观品质性状及相关性进行了研究分析。结果表明,127个组合的加工和外观品质性状中差异程度最大的是垩白度,其次是垩白粒率,最小的是糙米率;优质达标率最高的是糙米率为100％,其次是整精米率为81．89％,较低的是垩白粒率和垩白度,仅为4．72％和7．87％;整精米率与长宽比、垩白粒率、垩白度呈极显著负相关,长宽比与垩白粒率、垩白度呈极显著负相关,垩白粒率与垩白度呈极显著正相关。垩白粒率高、垩白度大是提升籼型杂交稻组合米质的重要制约因素,建议从提高整精米率和增大长宽比来降低或减少垩白粒率和垩白度,同时加强高密度、无裂纹和宽厚比小的米粒选择,增强稻米的耐碾磨能力,使所选育材料和组合在加工和外观品质上得以同步改良。     

播期对水稻产量米质及抗稻瘟病性影响研究初探

探讨了不同播种期对水稻产量品质抗瘟病性影响,结果表明,随着播期和移栽期的拖后产量都有降低的趋势;不同处理间的加工品质有一定的差异,表现在糙米率、精米率、整精米率降低,对外观品质方面的垩白米率的影响更为明显,随着播期的拖后,垩白米率在降低,但对蒸煮食味品质的影响不大,处理间无明显差异。发病率有随着播期拖后而有下降的趋势,最佳播种期为4月14～20日。     

辽宁省中晚熟水稻新品系品质性状的研究

以辽宁省中晚熟水稻新品系为试验材料,以辽粳9号为对照,对辽宁省中晚熟水稻新品系的主要品质性状进行了研究。结果表明:加工品质中辽宁省中晚熟水稻新品系的糙米率、精米率和整精米率都低于对照,互相之间呈极显著正相关;外观品质中新品系的粒长、长宽比、垩白粒率和垩白度都高于对照;蒸煮食味品质和营养品质中新品系的碱消值和胶稠度低于对照,直链淀粉含量和蛋白质含量高于对照,直链淀粉含量与蛋白质含量呈极显著负相关。     

Impact of field-scale nighttime air temperatures during kernel development on rice milling quality

Recent research has shown that elevated nighttime air temperatures (NTATs) may contribute to increased chalk and reduced milling quality. The objective of this study was to develop a method to quantify the effects of elevated NTATs on chalk formation and peak head rice yield (pHRY) in field-grown rice cultivars. To do so, 95th percentiles of NTAT frequencies (NT₉₅) occurring during reproductive (R) stages of Bengal, Jupiter, Cypress, LaGrue, Wells, and XL723 cultivars were correlated with chalk levels and pHRYs observed during the 2007 through 2009 harvest seasons. Chalk levels were strongly correlated with NT₉₅ during the R7 and R8 stages for all cultivars, except Bengal. Peak HRYs of Cypress, LaGrue, Wells, and XL723 were linearly and inversely related to NT₉₅ occurring during the R8 stage, while pHRYs of Bengal and Jupiter showed no significant correlations with this percentile at any R-stage. Although strong correlations of chalk levels and pHRYs with NT₉₅ were observed during the R8 stage of cultivar development, it is speculated that rice plants classified in this stage actually exhibit many kernels that lag in development and exist in the R6 and R7 grain-filling stages, where elevated NTATs are thought to have deleterious effects on chalk levels and milling quality.     

Extreme nighttime air temperatures in 2010 impact rice chalkiness and milling quality

Research shows that elevated nighttime air temperatures (NTATs) contribute to increased chalk formation and reduced milling quality in rice. Arkansas rice-growing regions experienced exceptionally warm weather conditions during the summer of 2010, providing an opportunity to test this hypothesis under extreme conditions. Data from a previous study, conducted in years 2007-2009 (Ambardekar et al., 2011), was extended to include 2010 data, and analyzed to evaluate the correlations of 95th percentiles of NTAT frequencies (NT₉₅) occurring during reproductive (R) stages of six rice cultivars with chalk and peak head rice yields (pHRYs). Long-grain cultivars produced chalk values that were positively correlated to NT₉₅, and pHRYs that were inversely correlated, during the R5 through R8 stages. Medium-grain cultivars, Bengal and Jupiter, which in the original study showed little or no response to elevated NTATs during all R-stages, showed significant positive correlations between chalk, and negative correlations between pHRY, and NT₉₅, during the R7 and R8 stages. The 2007-2009 analyses indicated quadratic relationships of chalk with NT₉₅ and linear relationships of pHRY with NT₉₅. However, addition of the 2010 data indicated that both of these relationships were quadratic in nature. The extreme temperatures observed in 2010 also verified that while cultivars vary in their level of resistance to NTAT effects, all of the rice cultivars analyzed throughout the four-year study exhibited some degree of susceptibility to extreme NTAT temperatures occurring during critical grain-filling stages.     

盘锦地区稻米品质与灌浆期光合速率相关性研究

以2010年辽宁省盐碱地研究所试验点省区试中晚熟组部分水稻品种为试材,测定稻米品质及水稻群体光合速率,结果表明：水稻品种间稻米品质及群体光合速率均存在差异,齐穗后14 d左右时水稻群体光合速率与稻米的垩白粒率、垩白度呈显著或极显著正相关。     

辽宁省水稻品种外观品质性状分析

以近年来辽宁省审定的77个水稻品种为试材,对辽宁省水稻品种外观品质性状进行了分析。结果显示,辽宁省水稻品种间外观品质性状差异较大,垩白粒率、垩白度变异幅度最大。垩白、粒形、透明是影响稻米外观品质的主要因子。性状间只有粒长与籽粒长宽比、垩白粒率与垩白度、粒长与透明度相关达到极显著或显著水平。中等粒长品种垩白性状和透明程式度较好,为品种外观品质改良和田间选择提供了依据。同时,探讨了在水稻品质改良中种质资源利用问题。     

浅谈吉林省新育成水稻品种(系)米质分析现状

选取吉林省2007年～2011年新育成并参加省区域试验的611个品种(系)的米质分析,结果表明:晚熟品种的米质状况最好,中熟和中晚熟品种的品质相对较差。在品质性状上,糙米率、透明度、直链淀粉含量有92%以上品种能够达到国家一、二级标准,但是垩白粒率、垩白度、整精米率是制约吉林省水稻稻米品质达到国家一、二级标准的主要因素。     

Mapping QTLs for milling yield and grain characteristics in a tropical japonica long grain cross

Percent milling yield is an economically important trait of commercial rice because it largely determines the price that farmers receive for their crop. Analyzing 22 trait variables including milling yield, grain dimensions, chemistry and appearance, we identified 43 quantitative trait loci (QTLs) in a long grain japonica by long grain japonica cross. We report one QTL explaining 20% of the variation in brown rice recovery; two QTLs explaining 14% and 13% of the variation in milled rice recovery; and one QTL explaining 14% of the variation in head rice (HR) recovery. QTLs for the proportion of pre-broken brown rice kernels, seed density, amylose content, and kernel whiteness and chalkiness were found in the same region as the HR QTL. QTLs explaining up to 54% of the variation in grain shape measurements were identified and mapped to areas independent from those identified for milling yield. Analyses of grain appearance traits identified two QTLs for chalk in brown rice and one in head rice, and a QTL explaining up to 33% of the variance in green kernel area. Our results confirm previous findings on the multigenically complex nature of milling yield.     

淮北地区全降解育秧钵盘与平盘机插稻栽培比较

通过比较2种育秧盘机插稻生产力,为大面积水稻机械化及轻简化栽培提供最优农机农艺融合方案。结果显示:降解育秧钵盘处理秧苗在水稻茎基宽、单株分蘖数、百株地上部鲜质量均优于普通平盘育秧。同时,降解钵盘采用上毯下钵设计,调节插秧机取秧量可实现按钵精确机插,对秧苗根系植伤较轻,移栽后较普通平盘活棵快,分蘖发生早,在更短的时间内达到了预期穗数,穗粒结构较对照更为适宜,穗粒数均匀、变异系数小。收获期2个处理产量水平达到显著差异(P<0.05)。降解钵盘处理在一定程度上提高了糙米率、整精米率,降低了垩白率,效益较对照增加70.04元/667 m₂。     

High temperature and low solar radiation during ripening differentially affect the composition of milky-white grains in rice (Oryza sativa L.)

ABSTRACT

Temperatures and solar radiation during ripening critically affect grain appearance in rice (Oryza sativa L.). Climatic factors to induce chalky grains were analyzed under the experimental conditions of high-temperature and shading treatment and also under the ambient condition in a high-temperature-prone region of Japan. The frequency of white-back (WB) and basal-white (BW) grains correlated with temperature and solar radiation, whereas that of milky-white (MW) grains was not correlated, suggesting that complicated climatic factors are involved in the formation of MW grains. Further investigation was carried out to identify the parameters that distinguish perfect and MW grains grown in high-temperature versus those grown in low-solar-radiation conditions. As reported previously, the chalk phenotypes in the transverse section of the MW grains were quite different between environments: oval-shaped chalk for MW grains grown in low-solar-radiation condition and center chalk for MW grains grown in high-temperature condition. Grain hardness and amylopectin chain-length distribution did not explain the difference in MW grains between environments. MW grains subjected to high temperatures had a lower protein content without a consistent reduction in the single-grain weight, whereas those from the low-solar-radiation condition had a lower amylose content with a consistent reduction in the single-grain weight, when compared with perfect grains that developed in either environmental condition. Overall, our results suggest that MW grains are formed through different physiological mechanisms with altered starch and protein synthesis under high-temperature and low-solar-radiation conditions.

Abbreviations: BW: basal-white; DAH: days after heading; DP: degree of polymerization; MW; milky-white WB: white-back