Estimating wheat spike-leaf composite indicator(SLI)dynamics by coupling spectral indices and machine learning

The contribution of spike photosynthesis to grain yield(GY)has been overlooked in the accurate spectral prediction of yield.Thus,it’s essential to construct and estimate a yield-related phenotypic trait considering spike photosynthesis.Based on field and spectral reflectance data from 19 wheat cultivars under two nitrogen fertilization conditions in two years,our objectives were to(i)construct a yield-related phenotypic trait(spike–leaf composite indicator,SLI)accounting for the contribution of the spike to photosynthesis,(ii)develop a novel spectral index(enhanced triangle vegetation index,ETVI3)sensitive to SLI,and(iii)establish and evaluate SLI estimation models by integrating spectral indices and machine learning algorithms.The results showed that SLI was sensitive to nitrogen fertilizer and wheat cultivar variation as well as a better predictor of yield than the leaf area index.ETVI3 maintained a strong correlation with SLI throughout the growth stage,whereas the correlations of other spectral indices with SLI were poor after spike emergence.Integrating spectral indices and machine learning algorithms improved the estimation accuracy of SLI,with the most accurate estimates of SLI showing coefficient of determination,root mean square error(RMSE),and relative RMSE values of 0.71,0.047,and 26.93%,respectively.These results provide new insights into the role of fruiting organs for the accurate spectral prediction of GY.This high-throughput SLI estimation approach can be applied for wheat yield prediction at whole growth stages and may be assisted with agronomical practices and variety selection.

Systematic identification of wheat spike developmental regulators by integrated multiomics, transcriptional network, GWAS, and genetic analyses

The spike architecture of wheat plays a crucial role in determining grain number,making it a key trait for optimization in wheat breeding programs.In this study,we used a multi-omic approach to analyze the transcriptome and epigenome profiles of the young spike at eight developmental stages,revealing co-ordinated changes in chromatin accessibility and H3K27me3 abundance during the flowering transition.We constructed a core transcriptional regulatory network(TRN)that drives wheat spike formation and experimentally validated a multi-layer regulatorymodule involving TaSPL15,TaAGLG1,and TaFUL2.By integrating the TRN with genome-wide association studies,we identified 227 transcription factors,including 42 with known functions and 185 with unknown functions.Further investigation of 61 novel transcription factors using multiple homozygous mutant lines revealed 36 transcription factors that regulate spike architecture or flowering time,such as TaMYC2-A1,TaMYB30-A1,and TaWRKY37-A1.Of particular interest,TaMYB30-A1,downstream of and repressed by WFzP,was found to regulate fertile spikelet number.Notably,the excellent haplotype of TaMYB30-A1,which contains a C allele at the WFzP binding site,was enriched during wheat breeding improvement in China,leading to improved agronomic traits.Finally,we constructed a free and open access Wheat Spike Multi-Omic Database(http://39.98.48.156:8800/#/).Our study identifies novel and high-confidence regulators and offers an effective strategy for dissecting the genetic basis of wheat spike development,with practical value forwheat breeding.

Inheritance and Availability of High Grain Number Per Spike in Two Wheat Germplasm Lines

Grain number per spike （GNPS） is a major factor in wheat yield breeding. The development of high GNPS germplasm is widely emphasized in wheat-yield breeding. This paper reported two high GNPS wheat germplasm lines, Pubing 3228 and Pubing 3504, which had a stable and wide adaptability to different ecological regions. By exploring a nested cross design with reciprocals using Pubing 3228 or Pubing 3504 as a common parent and investigating the GNPS phenotypes of F1 hybrids in 2007-2008 and F2 populations in 2008-2009 of different cross combinations, the narrow-sense GNPS heritability was up to 49.58 and 52.23%, respectively. Genetic model analysis predictions suggested that GNPS in Pubing 3228 and Pubing 3504 was mainly controlled by additive genetic effects. Correlation analysis results between GNPS and 1 000- kernel weight （TKW） of F2 populations showed that TKW was not influenced with the increase of GNPS. The good coordination among three yield components of spike number per plant （SNPP）, GNPS, and TKW in the F2 segregating population implied that selection of good candidate individuals in breeding programs would be relatively straightforward. Overall, our results indicated that Pubing 3228 and Pubing 3504 are two potential germplasm lines for yield improvement of GNPS in pedigree selection of wheat breeding.

Changes in the Activities of Enzymes Involved in Starch Synthesis in the Kernel During Grain Filling in Winter Wheat Cultivars of Different Spike Types

Two winter wheat(Triticum aestivum L.)cultivars, large-spike type Yumai66 and small-spike type Yumai49, were used to study the activities of enzymes involved in starch synthesis in the kernel during grain filling. Starch accumulated faster in the kernel of Yumai49 than Yumai66 up to 25 d after anthesis, thereafter starch accumulated faster in the kernel of Yumai66. Starch accumulation in Yumai66 peaked at 20 -25 d after anthesis, while in Yumai49 starch accumulation peaked at 15 -20 d after anthesis and 25 -30 d after anthesis. The first peak was much higher than that of the second. Sucrose content and sucrose synthase activity peaked at 20 and 15 d after anthesis in Yumai66 and Yumai49, respectively. The sucrose content and sucrose synthase activity in Yumai66 were higher than that in Yumai49 during grain filling. ADP-glucose pyro-phosphorylase and starch branching enzyme activity in the kernel of Yumai66 peaked at 20 d after anthesis. while soluble starch synthase activity peaked at 10 and 20 d after anthesis. The second peak was much higher than that of the first.

Photosynthetic characteristics and nitrogen distribution of large-spike wheat in Northwest China

The leaf photosynthesis and nitrogen（N） translocation in three large-spike lines and control cultivar（Xi＇nong 979） of winter wheat（Triticum aestivum L.） were studied in 2010–2011 and 2011–2012. The objectives of this study were to investigate the differences in the physiological characteristics of large-spike lines and control cultivar and identify the limiting factors that play a role in improving the yield of breeding materials. The average yield, grain number per spike, kernel weight per spike, and 1 000-kernel weight of the large-spike lines were 16.0, 26.8, 42.6, and 15.4%, respectively, significantly higher than those of control. The average photosynthetic rates（Pn） were not significant between the large-spike lines and control cultivar during the active growth period. The average PSII maximum energy conversion efficiency（Fv/Fm）, PSII actual quantum efficiency（Ф（PSII））, photochemical quenching coefficient（qP）, PSII reaction center activity（Fv′/Fm′） and water-use efficiency（WUE） of the large-spike lines were 1.0, 5.1, 3.6, 0.8, and 43.4%, respectively, higher than those of the control during the active growth stages. The N distribution proportions in different tissues were ranked in the order of grains〉culms＋sheathes〉rachis＋glumes〉flag leaves〉penultimate leaves〉remain leaves. This study suggested that utilization of the large-spike wheat might be a promising approach to obtain higher grain yield in Northwest China.

The spike weight contribution of the photosynthetic area above the upper internode in a winter wheat under different nitrogen and mulching regimes

Besides leaves, non-foliar green organs such as stem and spike are also considered photosynthetic organs. To assess the photosynthetic contributions of these organs, the correlations between these photosynthetic areas and single-spike weight were investigated in a winter wheat(Triticum aestivum L.) under four nitrogen and mulching treatments: N120,N150, N195, and N195 + M. Two-year repeated field experiments were conducted on the Loess Plateau of China. Non-foliar photosynthetic area, grain-filling ratio and duration,grain yield, and in particular, single-spike weight, were measured, recorded and analyzed.Under the N195 + M treatment, plants showed the largest area of photosynthetic organs(flag leaf and non-foliar organs) and the highest grain yield and single spike weight. Singlespike weight was positively correlated with the areas of all examined non-foliar photosynthetic organs, in particular with the area above the flag leaf node(R^2= 0.761*)and the area above the exposed part of the peduncle(EXP)(R^2= 0.800**). In addition, singlespike weight was highly correlated with average grain-filling ratio(R^2= 0.993**), whereas it was less highly correlated with grain-filling duration(R^2= 0.533). The morphological traits of non-foliar photosynthetic organs were also more highly correlated with average grainfilling ratio than with average grain-filling duration. The significant correlation between each of the morphological traits(area, length and width) of EXP and single-spike weight indicates that morphological traits of EXP are important in determining spike weight in the Loess Plateau environment.

Gene and protein expression profiling analysis of young spike development in large spike wheat germplasms

The wheat grain number per spike （GNPS） is a major yield-limiting factor in wheat-breeding programs. Germplasms with a high GNPS are therefore valuable for increasing wheat yield potential. To investigate the molecular characteristics of young spike development in large-spike wheat germplasms with high GNPS, we performed gene and protein expression profiling analysis with three high-GNPS wheat lines （Pubing 3228, Pubing 3504 and 4844-12） and one Iow-GNPS control variety （Fukuho）. The phenotypic data for the spikes in two growth seasons showed that the GNPS of the three large-spike wheat lines were significantly higher than that of the Fukuho control line. The Affymetrix wheat chip and isobaric tags for relative and absolute quantitation-tandam mass spectrometry （iTRAQ-MS/MS） technology were employed for gene and protein expression profiling analyses of young spike development, respectively, at the floret primordia differentiation stage. A total of 598 differentially expressed transcripts （270 up-regulated and 328 down-regulated） and 280 proteins （122 up- regulated and 158 down-regulated） were identified in the three high-GNPS lines compared with the control line. We found that the expression of some floral development-related genes, including Wknoxlb, the AP2 domain protein kinase and the transcription factor HUA2, were up-regulated in the high-GNPS lines. The expression of the SHEPHERD （SHD） gene was up-regulated at both the transcript and protein levels. Overall, these results suggest that multiple regulatory pathways, including the CLAVATA pathway and the meristem-maintaining KNOX protein pathway, take part in the development of the high-GNPS phenotype in our wheat germplasms.

Comparative Proteomic Analysis of Spike-Development Inhibited and Normal Tillers of Wheat 3558

Spike number is one of three yield-related factors and is closely related to wheat yield. In the present study, we found that the inhibited and normal tillers of the 3558 line presented phenotypic differences at the elongation stage by morphological and anatomical analysis. We then initiated a proteomic study using two-dimensional electrophoresis （2-DE） and nano- scale liquid chromatography-high-definition tandem mass spectroscopy, to isolate and identify the key proteins and metabolic pathways related to spike-development inhibition. A total of 31 differentially expressed proteins （DEPs）, which were mainly involved in cell cycle regulation, photosynthesis, glycolysis, stress response, and oxidation-reduction reactions, were isolated and identified. 14-3-3-1ike proteins and proliferating cell nuclear antigen （PCNA）, involved in cell-cycle regulation, were dramatically down-regulated in inhibited tillers compared to normal tillers. Six spots corresponding to degraded Rubisco large subunits, involved in photosynthesis, were detected in different locations of the 2-DE gels and were up-regulated in inhibited tillers. In addition, the relative levels of DEPs involved in glycolysis and oxidation- reduction reactions changed dramatically. Development was blocked or delayed at the elongation stage in the inhibited tillers of 3558. Weakened energy metabolism might be one reason that the inhibited tillers could not joint and develop into spikes. These DEPs and related metabolic pathways are significant for understanding the mechanism of spike-development inhibition and studying the spike-development process in wheat.

Effects of Crown Ether on Some Physiological Properties and Economic Characteristics of Spikes of Wheat and Panicles of Rice

The seeds of wheat and the young roots of rice were treated with SU15-C-5 and B15-C-5.The effects of crown ether on economic characters of the spike and some physiological properties in both crops were studied.The results showed that crown ethers could promote the growth of wheat seedling, improve the contents of chlorophyll (a+b), reduce the ratio of chlorophyll a to b in the leaves of rice,thus bring about good effects of economic characters of the spike. Especially, it suggests that SU15-C-5 showed better physiological effects than B15-C-5.

不同季秸秆还田对冬小麦不同穗粒位结实粒数和粒重的影响

为探讨安徽淮北平原砂姜黑土区长期秸秆连续全量还田对冬小麦穗部结实特性的影响,2021-2022年基于农业农村部华东地区作物栽培科学观测站13年的长期定位试验,比较分析了小麦单季秸秆全量粉碎覆盖还田(T1)、小麦玉米秸秆全量粉碎还田(T2)、玉米秸秆全量粉碎翻埋还田(T3)、小麦玉米秸秆全年不还田(CK)4个不同还田模式下小麦不同小穗位结实粒数及粒重的差异。结果表明,T1、T2、T3处理的主茎穗小穗结实总粒数较CK分别提高了21.21%、7.50%和12.55%;第2粒位(G2)结实粒数分别提高了7.71%、7.71%和5.79%;上部小穗结实粒数分别提高了51.41%、22.79%和31.36%,其G2结实粒数分别提高了30.95%、30.95%和23.09%,其中T1处理对小麦粒数的提升效果最好。不同季秸秆还田处理下小麦主茎穗及其G2粒重、分蘖穗及其第三粒位(G3)粒重均高于CK,T1、T2和T3处理的主茎穗粒重增幅分别为16.06%、4.14%和16.06%,分蘖穗增幅分别为9.86%、0.71%和8.87%;T1、T2和T3处理下主茎穗G2粒重增幅分别为20.69%、10.34%和17.24%,分蘖穗G3粒重4.55%、2.27%和6.82%,其中T1处理对粒重提升效果最好,其次是T3。综合来看,在安徽淮北平原砂姜黑土区长期秸秆还田能够提高小麦穗粒数和粒重,进而促进产量提升,其中T1处理对小麦结实粒数和粒重的提升效果最好,是适宜在该地区推广的秸秆还田模式。

基于改进Mask R-CNN的小麦在穗籽粒表型参数测试方法

【目的】针对小麦籽粒性状参数获取需要脱粒后测量,测量程序繁杂、费时费力的缺点,提出基于深度学习的小麦在穗籽粒表型参数测试方法。【方法】采集镇麦25、宁麦13和农麦88这3个品种小麦穗两侧正视图像,利用小麦穗正视图像构建图像增强数据集,提出深度学习与形态学处理相结合的小麦在穗籽粒表型参数测试方法。首先,建立基于改进Mask R-CNN网络的麦穗颖壳分割模型,模型以ResNet和FNP为特征提取网络并引入坐标注意力(CA)模块、聚合模块和半卷积模块,实现麦穗图像中颖壳的准确定位、分割和籽粒计数。其次,利用分割的麦穗颖壳掩膜图经形态学处理方法提取麦穗颖壳的5个表型参数,并建立麦穗颖壳表型参数与颖壳内籽粒表型参数之间的线性相关关系。最后,利用麦穗颖壳表型参数与籽粒表型参数之间的线性相关关系预测籽粒表型参数。【结果】(1)基于改进Mask R-CNN网络的麦穗颖壳分割模型的平均精确率AP为94.13%,F1值为91.12%,召回率为88.30%,单幅图像平均检测耗时97 ms,可以快速、精准地识别单粒麦穗颖壳。模型的籽粒计数的均方根误差和平均相对误差分别为0.94个和0.65%,可见模型分割籽粒的精度较高。(2)麦穗颖壳与籽粒之间的表型参数粒长、粒厚、面积、周长、长径比线性相关关系式为:y=0.7258x、y=0.5166x、y=0.3748x、y=0.6756x、y=1.4085x,其决定系数(R2)均在0.85以上。(3)利用图像获取的麦穗颖壳参数数据对上述相关性模型进行验证并预测籽粒表型参数,粒长、粒厚、面积、周长、长径比5个参数的均方根误差和平均相对误差分别为0.17 mm、0.08 mm、0.46 mm^(2)、0.33 mm、0.12和0.02%、0.02%、0.02%、0.02%、0.03%,每个参数的预测数据与实际数据之间的决定系数(R2)均在0.85以上,说明本文提出的籽粒表型预测方法可行。【结论】基于深度学习的小麦在穗籽粒表型测试方法能够通过麦穗颖壳表型参数精确预测小麦在穗籽粒的表型参数,为快速简便提取小麦籽粒表型参数提供了新的方法。

小麦穗型相关生长素通路基因发掘及TaARF23-A与小穗数关联分析

生长素是调控作物穗部形态的主要内源激素之一。为了发掘小麦中与穗型相关的生长素通路基因,本研究选择了纺锤穗型品系SY95-71和密穗品系CH7034,对其幼穗内源生长素含量进行了检测,结果显示SY95-71幼穗中的色胺含量显著高于CH7034。转录组测序结果表明,在高置信区间(P<0.01)范围内, SY95-71幼穗中富集到4个特有的生长素相关条目,并且色氨酸脱羧酶基因(负责将色氨酸转化为色胺)和生长素响应因子基因(Auxin Response Factors,ARFs)的转录水平均显著高于CH7034。对在SY95-71中高表达的2个ARF基因(TraesCS7A02G475700和TraesCS7A02G475600)作了进一步分析,结果显示二者是位于7A染色体长臂上的一对串联重复基因,根据小麦ARF家族成员编号,将其分别命名为TaARF23-A1和TaARF23-A2。qRT-PCR结果证实SY95-71幼穗中TaARF23-A1和TaARF23-A2的表达量极显著高于CH7034。测序结果显示TaARF23-A的外显子序列在SY95-71和CH7034间具有2个SNP和1个InDel。根据InDel位点开发分子标记,并将其与SY95-71和CH7034的RILs群体在6个大田环境下的穗部表型进行关联分析,结果显示TaARF23-A与小穗数显著相关(P<0.0001),其CH7034型等位变异比SY95-71型等位变异增加了1.67个小穗。本研究结果将为小穗发育机制解析提供参考,也为小麦理想穗型改良提供了分子标记。

播期对不同穗型冬小麦生长及产量的影响

为提高冬小麦产量,开展播期对不同穗型冬小麦生长及产量影响的研究。本研究以大穗型品种‘泰农18’、中穗型品种‘山农18’和多穗型品种‘红地95’为试验材料,设置9月30日、10月10日、10月20日、10月30日4个播期,对不同播期条件下的株高、叶面积指数、茎蘖数、产量及产量三要素进行测定。结果表明,随着播期推迟,‘泰农18’、‘山农18’、‘红地95’的株高呈下降趋势,叶面积指数、单位面积茎蘖数、穗数、穗粒数、千粒重和产量均呈现先上升后下降的趋势。产量在播期为10月10日时最高,分别为9.38 t/hm^(2)、8.94 t/hm^(2)、9.22 t/hm^(2),播期为10月30日时最低,分别为7.26 t/hm^(2)、7.32 t/hm^(2)、7.74 t/hm^(2),比最高处理分别下降22.6%、18.1%、16.1%。通过对3个品种产量和三要素之间的通径分析可知,播期主要影响大穗型品种‘泰农18’的穗粒数,中穗型品种‘山农18’的千粒重,多穗型品种‘红地95’的单位面积穗数。综合比较,3个品种的最适播期均为10月10日,晚播可造成株高、叶面积指数、茎蘖数下降,产量降低。

小麦单株穗数的QTL定位及CAPS标记开发

穗数是小麦产量构成三要素之一,开展小麦成穗数研究,对高产育种及种质资源创制具有重要意义。本研究以安农859/武农988的135份DH群体为研究材料,分别测定两年五个环境下单株穗数表型值,并基于DH群体的55K芯片数据进行单株穗数QTL分析,开发CAPS分子标记。结果表明,在1B、1D、2A、3D、4A、4B、4D、6A、7D等染色体上共检测到21个与单株穗数相关的QTL,其中,位于4B染色体上的Qsn-ahau-4B.2在5个环境下均被检测到,侧翼标记为AX-95004669-AX-109580651,物理区间为2.65Mb,可解释16.92%~49.98%表现变异,加性效应为1.32~3.69个穗数,增效等位基因来自安农859,是一个主效、稳定的QTL。基于Qsn-ahau-4B.2区间内候选基因TraesCS4B01G042700开发一个多态性CAPS标记(T-0507)。本研究结果将为小麦单株成穗数研究提供参考。

适用于嵌入式设备的轻量级深度学习网络RepYOLO

提出了一种轻量级深度学习网络模型RepYOLO算法,并将其移植到嵌入式设备MCU/MPU中。该网络模型RepYOLO以YOLOv4为基础网络模型,通过改进YOLOv4的主干网络CSPDarkNet为RepBlock结构、在Neck层中引入CBAM注意力机制以及在Head层替换anchor-based检测头为anchor-free检测头并加入ATSS算法减小计算量、提高推理速度和检测精度。结果表明,与原YOLOv4模型相比,网络模型RepYOLO在小麦穗检测上表现出更显著的优势,其精度率、召回率、F1值和平均精度均值分别提高了4.7、3.6、1.5、1.7个百分点;此外,RepYOLO在嵌入式设备MCU/MPU上的推理时间分别降低了37.03%和41.44%。

黄淮麦区南片两个国审小麦品种穗分化特性及抗倒春寒能力的鉴定与分析

为鉴定黄淮南片麦区国审小麦品种西农100和小麦区域试验对照品种“周麦18”的抗倒春寒能力,采用大田试验调查穗分化特征,人工气候室低温胁迫处理6 h、12 h、24 h后测定结实率、叶片逆境生理指标和显微结构等,并分析了两个品种各个指标间的差异与变化特点。结果表明:在陕西关中大田条件下,西农100比周麦18的穗分化进程提前;倒春寒低温胁迫促使西农100小麦旗叶的SOD与CAT活性增加,而可溶性糖含量显著低于周麦18;同时,低温胁迫使小麦叶片显微结构中厚壁组织出现明显分解与萎缩,西农100低温胁迫6 h叶片厚度较CK(未处理)未发生变化,周麦18叶片厚度则明显减小,低温胁迫12 h以后,两个品种无明显差异。本研究表明,西农100和周麦18都具有一定的抗倒春寒特性,而西农100的抗倒春寒能力相对较强。

秸秆覆盖与施磷对旱地小麦小花发育与结实特性的影响

中国西南丘陵旱地气候冬干春旱且速效磷缺乏,是冬小麦生产的主要限制因素。为明确秸秆覆盖与施磷对西南丘陵旱地小麦小花发育与结实特性的影响,以川麦104为供试材料,采用裂区设计,主区为玉米秸秆覆盖(SM)和不覆盖(NSM),裂区为0、75和120 kg P_(2)O_(5)·hm^(-2)3个施磷水平,比较分析了不同处理下小麦小花分化及结实特性的差异。结果表明,秸秆覆盖与施磷均可提高小麦小花分化数和可孕小花数,且磷素效应大于秸秆覆盖效应。与不施磷相比,施磷75和120 kg·hm^(-2)条件下最大分化小花数分别增加了17.4%和78.0%,可孕小花数分别增加27.0%和94.1%,小花存活率提高了16.5个百分点。施磷后穗基部可孕小花数和结实粒数增幅较大,穗中部和顶部增幅较小。与不施磷相比,施磷75和120 kg·hm^(-2)条件下,穗基部可孕小花数均极显著增加,增幅分别为100.0%和127.2%;结实粒数显著增加,增幅分别为186.4%和193.2%。秸秆覆盖后产量较不覆盖提高20.5%;施磷75和120 kg·hm^(-2)下产量较不施磷分别提高62.5%和78.1%。综上所述,秸秆覆盖配施磷肥可减少小花退化,增加可孕小花数和穗粒数有利于产量形成。

The soft glumes of common wheat are sterile-lemmas as determined by the domestication gene Q

The Q gene in common wheat encodes an APETALA2(AP2) transcription factor that causes the free threshing attribute. Wheat spikelets bearing several florets are subtended by a pair of soft glumes that allow free liberation of seeds. In wild species, the glumes are tough and rigid,making threshing difficult. However, the nature of these "soft glumes", caused by the domestication allele Q is not clear. Here, we found that over expression of Q in common wheat leads to homeotic florets at glume positions. We provide phenotypic, microscopy, and marker genes evidence to demonstrate that the soft glumes of common wheat are in fact lemma-like organs, or so-called sterile-lemmas. By comparing the structures subtending spikelets in wheat and other crops such as rice and maize, we found that AP2 genes may play conserved functions in grasses by manipulating vestigial structures, such as floret-derived soft glumes in wheat and empty glumes in rice. Conversion of these seemingly vegetative organs to reproductive organs may be useful in yield improvement of crop species.

郭予元院士在小麦害虫预测和治理上的学术贡献——纪念郭予元院士诞辰90周年

本文回顾了郭予元院士在小麦害虫预测和治理上的重要贡献,主要包括:在20世纪70-90年代,创新了害虫生物学与生态学有机结合方法,显著提升小麦害虫预测技术水平。从宏观到机理,突破了多项小麦害虫治理关键技术,包括小麦品种抗吸浆虫鉴定技术与抗吸浆虫机制,创新性提出吸浆虫成虫期防治及穗期保护策略;利用田间开放式控制虫量的办法建立小麦蚜虫防治阈值及复合防治指标;麦田天敌资源的保护及利用。面向小麦生产实际,创建小麦吸浆虫综合治理技术体系。吸浆虫穗期保护策略和技术、蚜虫防治指标与防治适期等研究成果一直传承至今,列入我国农业行业标准和国家标准。本文还介绍了在后续小麦吸浆虫、蚜虫预测与防控研究与实践中,传承与发展郭予元院士的学术思想,以及未来研究展望。

Characterization of Ppd-D1 alleles on the developmental traits and rhythmic expression of photoperiod genes in common wheat

Photoperiodic response is an important characteristic that plays an important role in plant adaptability for various environments. Wheat cultivars grow widely and have high yield potential for the strong photoperiod adaptibility. To assess the photoperiodic response of different genotypes in wheat cultivars, the photoperiodic effects of the Ppd-D1 alleles and the expressions of the related TaGI, TaCO and Ta FT genes in Liaochun 10 and Ningchun 36 were investigated under the short-day（6 h light, SD）, moderate-day（12 h light, MD） and long-day（24 h light, LD） conditions. Amplicon length comparison indicated that the promoter of Ppd-D1 in Ningchun 36 is intact, while Liaochun 10 presented the partial sequence deletion of Ppd-D1 promoter. The durations of all developmental stages of the two cultivars were reduced by subjection to an extended photoperiod, except for the stamen and pistil differentiation stage in the Liaochun 10 cultivar. The expression levels of the Ppd-D1 alleles and the TaGI, TaCO and TaFT genes associated with the photoperiod pathway were examined over a 24-h period under SD and MD conditions. The relationships of different photoperiodic responses of the two cultivars and the expression of photoperiod pathway genes were analyzed accordingly. The photoperiod insensitive（PI） genotype plants flower early under SD; meanwhile, the abnormal expression of the Ppd-D1 a allele is accompanied with an increase in Ta FT1 expression and the TaCO expression variation. The results would facilitate molecular breeding in wheat.