Selection and application of four QTLs for grain protein content in modern wheat cultivars

The grain protein content(GPC)is the key parameter for wheat grain nutritional quality.This study conducted a resampling GWAS analysis using 406 wheat accessions across eight environments,and identified four previously reported GPC QTLs.An analysis of 87 landraces and 259 modern cultivars revealed the loss of superior GPC haplotypes,especially in Chinese cultivars.These haplotypes were preferentially adopted in different agroecological zones and had broad effects on wheat yield and agronomic traits.Most GPC QTLs did not significantly reduce yield,suggesting that high GPC can be achieved without a yield penalty.The results of this study provide a reference for future GPC breeding in wheat using the four identified QTLs.

Effects of Sulfur Fertilizer Application Methods on Grain Protein Content During Filling Stage of Winter Wheat

[ Objective] The experiment aimed to provide a theoretical base of optimal cultivation management for the high yield and good quality and high efficiency of winter wheat. [ Method] The effects of two sulfur fertilizer application methods on dynamic changes of grain protein content and glutenin content of Yumai 49 and Yumai 66 during wheat grain filling stage were studied under the field conditions. [Result] Both the grain protein and glutenin content of two cultivars were increased by sulfur fertilizer, particularly, the effects on Yumai 49 were more significant.[ Conclusion] The grain content and glutenin content of different wheat cultivars could be increased by taking different sulfur fertilizer application methods.

Estimating Wheat Grain Protein Content Using Multi-Temporal Remote Sensing Data Based on Partial Least Squares Regression

Estimating wheat grain protein content by remote sensing is important for assessing wheat quality at maturity and making grains harvest and purchase policies. However, spatial variability of soil condition, temperature, and precipitation will affect grain protein contents and these factors usually cannot be monitored accurately by remote sensing data from single image. In this research, the relationships between wheat protein content at maturity and wheat agronomic parameters at different growing stages were analyzed and multi-temporal images of Landsat TM were used to estimate grain protein content by partial least squares regression. Experiment data were acquired in the suburb of Beijing during a 2-yr experiment in the period from 2003 to 2004. Determination coefficient, average deviation of self-modeling, and deviation of cross- validation were employed to assess the estimation accuracy of wheat grain protein content. Their values were 0.88, 1.30%, 3.81% and 0.72, 5.22%, 12.36% for 2003 and 2004, respectively. The research laid an agronomic foundation for GPC （grain protein content） estimation by multi-temporal remote sensing. The results showed that it is feasible to estimate GPC of wheat from multi-temporal remote sensing data in large area.

Amino acid permease 6 regulates grain protein content in maize

Grain protein content(GPC)is an indicator of cereal nutritional quality.Identification of genes involved in the regulation of GPC provides targets for molecular breeding for crop protein quality.We characterized a maize gene encoding the putative amino acid transporter ZmAAP6,a gene expressed mainly in immature seeds,especially in the basal endosperm transfer layer.Total protein and zein contents were decreased in ZmAAP6 null mutants and increased in ZmAAP6 overexpression(OE)lines,consistent with their changed in the size of protein bodies.Metabolic and transcriptomic analysis supported the regulatory role of ZmAAP6 in amino acid transportation.These results suggest that ZmAAP6 functions as a positive regulator of GPC in maize,shedding new light on the genetic basis of GPC regulation.

Predicting Grain Yield and Protein Content in Winter Wheat at Different N Supply Levels Using Canopy Reflectance Spectra

A field experiment using a split-plot randomized complete block design with three replications was carried out to determine relationships between spectral indices and wheat grain yield （GY）, to compare the performance of four vegetation indices （VIs） for GY prediction, and to study the feasibility of VI to estimate grain protein content （GPC） in winter wheat. Two typical winter wheat （Triticum aestivum L.） cultivars ＇Xuzhou 26＇ （high protein content） and ＇Huaimai 18＇ （low protein content） were used as the main plot treatments and four N rates, i.e., 0, 120, 210, and 300 kg N ha^-1, as the sub-plot treatments. Increasing soil N supply significantly increased GY and GPC （P ≤ 0.05）. For the two cultivars combined, significant and positive correlations were found between four VIs and GY, with the strongest relationship observed when using the green ratio vegetation index （GRVI） at mid-filling. Cumulative VI estimates improved yield predictions substantially, with the best interval being heading to maturity stage. Similar results were found between VI and grain protein yield. However, when using cumulative VI, GPC showed no significant improvement. The strong relationship between leaf N status and GPC （R2 =0.9144 for ＇Xuzhou 26＇ and R2 = 0.8285 for ＇Huaimai 18＇） indicated that canopy spectra could be used to predict GPC. The strong fit between estimated and observed GPC （R2 = 0.7939） indicated that remote sensing techniques were potentially useful predictors of grain protein content and quality in wheat.

Studies on Single Cell Culture in vitro in Wheat——The variation of grain protein content and its fractions from regenerated plants

On the basis of previous studies dealing with the variation of major agronomic and yield characteristics of regenerated plants derived from single cell culture in vitro of common wheat (Triticum aestivum L.Cultivar NE 7742), the grain protein content and its fractions from regenerated plants with stable agronomic characteristics were studied from 1992 to 1995. The results showed that the variation of grain protein content and its fractions in somaclones from single cell culture in vitro were very significant and the range was very wide (11531770%). Several types of variation were found in the studies, especially the type with higher protein content than that of cultivar NE 7742 (non-culture parent). Among them, -2069% of lines the grain protein content was significantly higher than that of NE 7742 and combined with high yielding potential. The tendency of variation of the four protein fractions showed that the variation of albumin was not obvious and maintained the same level as NE774 increased in some somaclones and decreased in others. However, the percentages both globulin and glutenin tended to increase. The variation of total amount of structural protein and the ratio between globulin and glutenin tended to increase. The variation of total amount of structural protein and the ratio between globulin and albumm was mainly influenced by globulin under the condition of culture in vitro. The variation of total amount of storage protein and the ratio between gliadin and glutenin was mainly affected by glutenin. The results mentioned above demonstrated that the induction and screening of somaclonal variation could be an effective way in wheat improvement in combining high protein content with high yield.

Genetic Analysis and Improvement Strategies of Protein Content in Rice Seeds

Enhancing the nutritional quality of food crops is a way to improve human nutrition and health. Grain protein content （ GPC ） is an important nutritional quality trait for rice and many other crops. Therefore, it will be very significant to increase GPC and improve rice quality. This paper mainly reviewed the genetic studies GPC in rice, mapping and cloning of QTLs and genes associated with GPC. However, little is known about the molecular mechanism and gene function related to GPC in rice. Thus, here we put forward the genetic strategy by gene pyramiding or molecular marker assisted selection to improve GPC and nutritional quality in rice. This review could provide important information for genetic improvement of grain nutritional quality of rice.

Identification of QTL Affecting Protein and Amino Acid Contents in Rice

The phenotypes of protein and amino acid contents were measured in an F9 recombinant inbred line population derived from a cross between Zhenshan 97B and Delong 208. A total of 48 and 64 QTLs were identified in 2004 and 2005, respectively. The contribution of each QTL to the phenotypic variation ranged from 4.0% to 43.7%. Most QTLs co-localized, forming 29 QTL clusters on the chromosomes with three major ones detected in both years, which were mapped on chromosomes 1, 7 and 9, respectively. The two QTL clusters for amino acid content, qAa1 and qAa7, influenced almost all the traits with the allele from Zhenshan 97B, and the third QTL cluster for amino acid content, qAa9, increased the lysine content with the allele from Delong 208. A wide coincidence was found between the QTL detected under this study and the loci involved in amino acid metabolism pathways in nitrogen assimilation and transport, or protein biosynthesis. The results would facilitate the identification of candidate genes and could be used in marker-assisted selection for the favorable allele in rice quality improvement.

Global sensitivity analysis of wheat grain yield and quality and the related process variables from the DSSAT-CERES model based on the extended Fourier Amplitude Sensitivity Test method

A crop growth model,integrating genotype,environment,and management factor,was developed to serve as an analytical tool to study the influence of these factors on crop growth,production,and agricultural planning.A major challenge of model application is the optimization and calibration of a considerable number of parameters.Sensitivity analysis(SA) has become an effective method to identify the importance of various parameters.In this study,the extended Fourier Amplitude Sensitivity Test(EFAST) approach was used to evaluate the sensitivity of the DSSAT-CERES model output responses of interest to 39 crop genotype parameters and six soil parameters.The outputs for the SA included grain yield and quality(take grain protein content(GPC) as an indicator) at maturity stage,as well as leaf area index,aboveground biomass,and aboveground nitrogen accumulation at the critical process variables.The key results showed that:(1) the influence of parameter bounds on the sensitivity results was slight and less than the impacts from the significance of the parameters themselves;(2) the sensitivity parameters of grain yield and GPC were different,and the sensitivity of the interactions between parameters to GPC was greater than those between the parameters to grain yield;and(3) the sensitivity analyses of some process variables,including leaf area index,aboveground biomass,and aboveground nitrogen accumulation,should be performed differently.Finally,some parameters,which improve the model’s structure and the accuracy of the process simulation,should not be ignored when maturity output as an objective variable is studied.

Changes in Activities of Glutamine Synthetase during Grain Filling and Their Relation to Rice Quality

Four japonica rice varieties differed in cooking and eating qualities were used in a pot experiment to study the relationship between the activities of glutamine synthetase during grain filling and rice quality. The activities of glutamine synthetase gradually increased and then declined as a single peak curve in the course of grain filling. The 15th day after heading was a turning point, before which the enzymatic activities in the inferior rice varieties with high protein content were higher than those in the superior rice varietie with low protein content, and after which it was converse. The activity of glutamine synthetase in grain was correlated with the taste meter value, peak viscosity and breakdown negatively at the early stage of grain filling whereas positively at the middle and late stages. Moreover, it was correlated with the protein content of rice grain and setback positively at the early stage and negatively at the middle and late stages. The correlation degree varied with the course of grain filling. From 15 days to 20 days after heading was a critical stage, in which the direction of correlation between the activity of glutamine synthetase and taste meter value and RVA properties of rice changed.

济麦44/济麦229重组自交系群体籽粒蛋白质含量QTL分析

小麦籽粒蛋白质含量与面团流变学特性及加工特性的关系密不可分。本研究在2020—2021年济南试验基地(E1)及2021—2022年济南试验基地(E2)和济阳试验基地(E3)三个环境下,以“济麦44×济麦229”构建的包含285个家系的重组自交系群体(F2∶6RILs)为材料,利用小麦55K SNP芯片构建高密度遗传连锁图谱,对籽粒蛋白质含量进行QTL分析。结果共筛选到2344个SNP标记用于构建遗传连锁图谱,图谱总长度3349.95 cM,平均标记密度为1.43 cM/标记。通过对籽粒蛋白质含量的QTL分析,共检测到18个籽粒蛋白质含量相关QTL,分布在1A、1B、2B、3D、4B、4D、5A、5B、5D、7A、7B共11条染色体上。Qpc.saas.4B-1在E1、E2和E3三个环境和BLUE(最佳线性无偏估计)值中均被稳定检测到,可以解释3.26%~23.79%的表型变异。Qpc.saas.4D和Qpc.saas.5A在两个环境和BLUE值中被检测到,分别解释2.42%~11.18%和2.48%~5.47%的表型变异,且Qpc.saas.4D与小麦矮秆基因Rht-D1b物理位置重合。本研究中检测到的QTL新位点Qpc.saas.4B-1、Qpc.saas.4D和Qpc.saas.5A是控制籽粒蛋白质含量的主效基因,具有高表型变异解释率。本研究结果可为小麦品质育种提供分子标记及理论参考。

施用有机肥和秸秆还田对旱地玉-麦二熟体系作物产量、品质和化肥效率的影响

为探明施用商品有机肥和秸秆还田对旱地夏玉米-冬小麦二熟体系作物产量、品质和肥料利用效率的影响,于2015—2020年度设置不施肥+秸秆不还田(CK)、施氮磷肥+秸秆不还田(NP)、施氮磷肥+秸秆不还田+商品有机肥(NPO)和施氮磷肥+秸秆还田(NPS)4个处理进行田间试验,测定并分析作物产量、氮磷肥农学效率、籽粒养分含量、蛋白质含量以及冬小麦籽粒中蛋白质组分含量。结果表明:(1)与NP和NPO处理相比,NPS处理夏玉米5 a平均产量分别显著提高21.33%和20.77%,周年产量分别显著提高9.99%和13.43%,但3个施肥处理间小麦产量差异不显著。(2)施用商品有机肥和秸秆还田对夏玉米、冬小麦的籽粒品质均有显著影响。与NP处理相比,NPO处理冬小麦籽粒各蛋白质组分含量提高5.69%~8.28%;NPS处理冬小麦籽粒氮含量、钾含量和各蛋白质组分含量分别提高4.68%、3.96%和7.75%~11.38%。相较于NPO处理,NPS处理冬小麦籽粒钾含量、谷蛋白含量、贮藏蛋白含量和谷醇比分别显著提高14.41%、9.86%、5.39%和9.65%,夏玉米籽粒蛋白质含量、产量和籽粒氮、籽粒磷含量以及周年蛋白质产量分别显著提高6.45%、28.89%、6.40%、23.08%和10.43%。(3)相较于NP和NPO处理,NPS处理夏玉米氮肥的农学效率分别提高118.35%和113.25%,周年氮、磷肥农学效率分别提高42.83%和64.36%、42.86%和64.27%,但3个施肥处理间冬小麦氮肥、磷肥农学效率5 a均值无显著差异。综合来看,长期施用商品有机肥和秸秆还田可改善冬小麦籽粒中的蛋白质组分特性,秸秆还田还能增加夏玉米籽粒钾含量和冬小麦籽粒蛋白质含量和蛋白质产量,秸秆还田较施用商品有机肥更利于提高旱地玉-麦二熟区作物产量、品质和肥料利用效率。综上所述,施氮磷肥+秸秆还田的管理模式更适宜在旱地玉-麦二熟区进行推广。

两个RIL群体中小麦籽粒品质相关性状QTL定位及KASP标记开发

本研究利用小麦55K SNP(55K single-nucleotide polymorphism)芯片和DArT(diversity array technology)标记对Avocet/Chilero和Avocet/Huites构建的两个F6重组自交系群体(recombinant inbred line,RIL)进行了小麦籽粒蛋白质含量(grain protein content,GPC)、湿面筋含量(wet gluten content,WGC)和沉降值(sedimentation value,SV)的QTL(quantitative trait loci)定位。共鉴定到68个与小麦籽粒蛋白质含量、湿面筋含量和沉降值相关的QTL,表型贡献率为3.60%~22.53%,其中,位于3A(2)、4D、5D(2)、6A(8)和7B染色体上的14个QTL可在多环境下被重复检测到。此外,在3A、3D、4B、5D、6A(2)和7B染色体上检测到7个QTL簇,位于3AS染色体9.32~60.01 Mb和6AS染色体38.47~82.95 Mb的稳定QTL簇C3A和C6A.2,同时与小麦籽粒蛋白质含量、湿面筋含量和沉降值显著相关,分别解释了6.55%~14.21%和3.83%~22.53%的表型变异。同时,在2个QTL簇中筛选到16个可能与籽粒蛋白质含量相关的候选基因,并根据候选基因开发了可供育种利用的KASP标记CGPC-6A-KASP-1和CGPC-6A-KASP-2。本研究为小麦籽粒品质相关性状的遗传改良提供了新的QTL位点和KASP标记,为分子标记辅助育种提供依据与参考。

耕作措施和施氮量对小麦籽粒产量、籽粒蛋白质含量和氮素利用率的影响

为明确黄淮海地区小麦产量、品质和氮素利用率协同提高的最优耕作和氮肥组合模式,于2018—2020年设置2 a大田定位试验,试验采用裂区设计,主区为耕作方式,分别为旋耕(R)、深耕(P)和深松(B);裂区为施氮量,分别为135 kg/hm^(2)(N135)、180 kg/hm^(2)(N180)、225 kg/hm^(2)(N225)、270 kg/hm^(2)(N270)。结果表明:耕作措施、施氮量及其互作对小麦籽粒产量、籽粒蛋白质含量和氮素利用率均有显著影响。深松较传统旋耕或深耕处理,小麦开花期、成熟期氮素积累量分别增加1.2%~18.9%、5.2%~16.3%,花前氮素转运量、花后氮素积累量分别增加0.8%~70.4%、5.7%~21.9%,植株氮素生产力、氮素利用率分别增加3.2%~21.1%、3.7%~40.7%,最终实现小麦籽粒产量、籽粒蛋白质含量和籽粒蛋白质产量分别提高3.7%~40.7%、3.6%~8.9%和3.0%~49.9%。在一定范围内,增加氮肥施用量可以促进小麦籽粒蛋白质含量的提高,但同时降低了氮素利用率。综合效应看,深松配合270 kg/hm^(2)施氮量可同时实现最高籽粒产量、籽粒蛋白质含量和籽粒蛋白质产量,且氮素利用率高于相同施氮量的旋耕、深耕处理。因此,就本试验区域而言,首选深松耕作方式并配合270 kg/hm^(2)施氮量可实现小麦产量和品质协同提高,同时维持较优的氮素利用率。

优质蛋白玉米‘荃玉9号’主要营养品质性状的QTL定位

油分、蛋白质和淀粉是玉米籽粒的主要营养成分,同时也是玉米重要的品质性状。为探索更多玉米品质相关的QTL,本研究以优质蛋白玉米‘荃玉9号’构建的F2:3群体为材料,通过方差分析和QTL定位方法,对玉米籽粒品质性状(包括油分、蛋白质和淀粉含量)进行了遗传分析。在新都和简阳2地共检测到24个品质性状QTL,其中仅与油分含量、蛋白质含量和淀粉含量相关的QTL分别为9、9和2个,与多个品质性状相关的QTL为4个,QTL在10条染色体上均有分布,单个QTL可解释的表型贡献率为1.92%~34.43%。染色体上Bin7.01(6399330~8305989)的QTL在2个环境同时被检测到,可以解释12.68%~18.13%的表型变异且有加性效应,是控制玉米油分含量的主效QTL。本研究为玉米品质改良的分子辅助育种工作提供了基础数据资料,为后续的育种实践提供了有力支撑。

高光谱成像技术在粮食品质检测中的应用

高光谱成像技术因具有快速、客观、范围广、非破坏性等优点,已被广泛应用于食品安全、医学诊断、工业检测等领域。为全面认识高光谱成像技术在粮食品质检测中的应用现状,归纳了高光谱成像技术的基本原理、主要构成及其数据处理与分析,并针对其在粮食品质检测中的应用,重点总结了在粮食检测中水分含量、蛋白质、淀粉及不完善粒的应用研究进展。同时,比较了深度学习与传统的机器学习在粮食品质检测中的应用,探讨高光谱成像技术在样本数据库构建、测量灵敏度、仪器便携化方面所面临的问题与挑战,进而提出改进措施,旨在为粮食的品质评价提供参考。

土壤肥力和施氮量对小麦氮素吸收运转及籽粒产量和蛋白质含量的影响

在不同土壤肥力条件下 ,研究了施氮量对小麦氮素吸收、转化及籽粒产量和蛋白质含量的影响 .结果表明 ,增施氮肥可以提高小麦各生育阶段的吸氮强度 ,尤以生育后期提高的幅度为大认为是增施氮肥提高小麦籽粒产量和蛋白质含量的基础 .增施氮肥虽提高了小麦植株的吸氮强度 ,吸氮量增加 ,但开花后营养器官氮素向籽粒中的转移率降低 .增施氮肥不仅促进了小麦植株对肥料氮的吸收 ,而且也促进了对土壤氮的吸收 .并讨论了在高、低土壤肥力条件下氮肥合理运筹的问题 .

施氮量和底追比例对小麦氮素吸收利用及子粒产量和蛋白质含量的影响

在大田栽培条件下,运用15N示踪技术研究了不同施氮量和底追肥比例对小麦氮素利用和子粒产量及蛋白质含量的影响。结果表明,施用氮肥提高了小麦植株的氮素积累量、子粒产量、蛋白质含量和蛋白质产量。相同施氮量条件下增加追肥氮的比例,提高了氮肥农学利用率和吸收利用率,增加了植株地上部器官(子粒+营养器官)中追肥氮、土壤氮的积累量,提高了营养器官中氮素的转运量和开花后氮素的同化量,增加了子粒蛋白质含量。相同的氮素底追肥比例条件下,将240 kg/hm2施氮量降至168 kg/hm2的处理,氮肥农学利用率、氮肥吸收利用率、氮肥偏生产力提高,子粒中土壤氮的积累量增加,植株地上部器官中土壤氮的积累量亦增加,开花后氮素同化量提高,子粒蛋白质含量增加。各施氮处理间子粒产量无显著差异。在本试验条件下,施氮量为168 kg/hm2且全部于拔节期追施是兼顾产量、品质和效益的优化处理。

硫对春小麦不同品质类型籽粒蛋白质及贮藏蛋白含量的效应

以 6个不同品质类型春小麦为材料 ,在不同氮水平条件下 ,研究施硫对小麦籽粒蛋白质含量和贮藏蛋白含量的调节效应。研究结果表明 ,施硫影响籽粒蛋白质含量 ,2 +12亚基组成品种籽粒蛋白质含量均在尿素 6 0kg hm2 (N6 0 )水平下配合一定的硫肥表现最好 ,5 +10亚基组成品种均在尿素 12 8kg hm2 (N1 2 8)水平下蛋白质含量较高。硫对籽粒蛋白质含量的影响与氮施用水平有关 ,在高氮条件下施硫可以增加籽粒蛋白质含量 ,尤其是更有利于高蛋白优质品种籽粒蛋白质含量的提高。低氮条件下施硫对醇溶蛋白含量的作用呈正效应。施硫可以增加籽粒谷蛋白含量 ,但只有在高氮条件下 ,施硫才有利于谷蛋白含量的提高 ,高蛋白优质品种东农 774 2、Roblin和NeepawaN1 2 8水平下的最高值高于N6 0 水平下的最高值 ,对这些品种来说 ,氮是限制硫充分发挥作用的因素 ,只有在高氮条件下 ,施硫才有利于谷蛋白积累。而高蛋白优质品种IE74和辽 10与低蛋白劣质品种新克旱 9在N6 0 水平条件下获得较高的谷蛋白含量。在高氮条件下 ,如果硫肥用量不足 ,谷蛋白含量反而不如低氮水平下供应适量的硫肥处理 ,与品种本身所要求氮和硫施用量和比例有关。

氮素水平对小麦籽粒产量和蛋白质含量的影响及其生理基础

在大田高产条件下研究了氮素水平对小麦籽粒产量和蛋白质含量的影响及其生理基础。结果表明 ,适当提高氮素水平既能增加小麦籽粒产量又能提高蛋白质含量 ,使籽粒产量和蛋白质含量达到同步增加 ,氮素水平过高虽能够提高籽粒蛋白质含量 ,但籽粒产量下降。适当提高氮素水平可以提高源器官碳素同化能力和氮素同化能力 ,又能够促进开花前暂贮于营养器官中的同化物质向籽粒中运转 ,增加籽粒中淀粉合成有关酶和氮素同化酶的活性 ,从而导致小麦籽粒产量和蛋白质含量同步增加。氮素水平过高 ,虽能促进源器官和籽粒中的氮素同化能力 ,但由于碳素同化酶和籽粒淀粉合成酶活性降低和开花前暂贮于营养器官中的同化物质向籽粒中的运转效率降低 ,而导致小麦籽粒蛋白质含量提高 ,产量下降。