Improvement Of Grain Yield Research Articles

Interactive effects of irrigation regime and planting density on grain yield and water use efficiency in winter wheat

To get an optimal irrigation regime and planting density for simultaneous improvement of grain yield (GY) and water use efficiency (WUE) in winter wheat, we examined the responses of 'Tainong 18' (with bigger ears) and 'Shannong 22' (with medium-sized ears) under four irrigation regimes, including 0, 45, 60, and 75 mm. Those two cultivars were planted at four densities: Tainong 18 at 135×104, 270×104, 405×104, and 540×104 plants·hm-2 and Shannong 22 at 90×104, 180×104, 270×104, and 360×104 plants·hm-2. The interactive effects of irrigation regimes and plant densities on GY, water consumption characteristics, and WUE were investigated. The results showed that GY, evapotranspiration, soil water consumption, and WUE were significantly affected by irrigation regime, plant density, and their interaction. The optimal irrigation regime was 45 mm for both cultivars, while the optimal plant density was 405×104 plants·hm-2 for Tainong 18 and 270×104 plants·hm-2 for Shannong 22, as indicated by the highest GY, the lowest ratio of soil evaporation to evapotranspiration after jointing, and higher WUE and the ratio of soil water consumption below 1 m to total soil water consumption. The rational combination of plant density and irrigation could reduce unnecessary water consumption and improve WUE.

Genetic variability and correlation analysis for yield and yield attributing traits in mungbean [Vigna radiata (L). Wilczek

Twenty mungbean (Vigna radiata (L.) Wilczek) genotypes were evaluated for the estimation of genetic variability parameters, correlation coefficient, path analysis, heritability and genetic advance. The genotypes differed significantly for all the characters. Higher GCV and PCV was observed for the seed index. High heritability coupled with genetic advance as percent of mean showed by harvest index indicating the impact of additive gene expression. The characters days to number of seeds per pod and harvest index showed positive and significant correlation along with positive direct effect on grain yield. Therefore, selection based on this component traits would results improvement in grain yield of mungbean.

The variability of grain yield, seed morphometric and vigour traits of early maturing hybrid maize

Breeding for yield and quality requires the assessment of the seed metrics and vigour traits. This study, therefore, assessed the variability and inter-dependence of grain yield (GY), seed morphometric and vigour traits in hybrid maize. Seeds of 75 early maturing hybrid maize varieties were evaluated for morphometric traits and quality in four replicates. A field trial laid out in a randomised complete block design with three replicates was also conducted in Ibadan, Nigeria, to determine the grain yield of the hybrids. Data collected on the GY, seed dimension and quality were subjected to analysis of variance. The least significant difference was used to separate means. Relationships among the GY, seed morphometric and vigour traits were determined using correlation coefficients, while principal component (PC) analysis was performed for variability among the hybrids. Significant differences (P<0.001) were found in the GY, seed dimension and vigour traits. Four of the nine highest yielding hybrids had ECT higher than 30.0 ?sg-1 cm-1. The GY correlated with seed diameter (SDT) (0.40**), seed width (SWD) (0.36**), seed length (SLG) (0.35**), seed area (SAR) (0.30**) and seed vigour (SVI) (0.30**). The SAG correlated with SDT, SLG, seed thickness (STH) and SAR. All the seed vigour traits correlated with one another. The PC I explained GY, SDT, SWD, SLG, SAR and SVI, indicating their importance in GY improvement. Seed angle, length and diameter were versatile in maize varietal selection. Identified high yielding hybrids with seed morphometric and vigour qualities can be explored by seed companies as innovation in the seed production business.

Assessment of Variability of Foxtail Millet [Setaria italica (L.) Beauv.] Genotypes

Analysis of genetic diversity and variability is an initial step for crop development in a plant breeding program. Thirty foxtail millet genotypes were evaluated for their ten agro-morphological traits viz. grain yield, days to heading, days to maturity, plant height, leaf length, leaf width, number of nodes per tiller, panicle length, thousand-grain weight, and leaf blast during April to August season of 2018 at Kabre, Dolakha, Nepal. Clustering was done based on variability observed among the genotypes for all the ten traits by the average linkage method. The genotypes were grouped into six clusters. The shortest inter cluster distance between Cluster I and Cluster II was 17.63 and the longest was between Cluster IV and Cluster VI with 47.55. Cluster I had the maximum leaf blast score with the minimum leaf length. The Cluster II had the maximum grain yield and days to 50% heading and the number of nodes per tiller. The Cluster III was characterized by the maximum leaf length and leaf blast value. The genotypes grouped into the Cluster IV were characterized by the lowest value of days to 50% heading and 80% days to maturity and those of Cluster V had the maximum thousand-grain weight. The genotypes categorized into Cluster VI had the maximum plant height, leaf length, and panicle length. Cluster II and Cluster V were good because of their agro-morphological traits. The presence of a high level of diversity among the genotypes indicated their suitability for selection in crop breeding programs. Correlation analysis of genotypes having the maximum panicle length leaf area and higher plant height and shorter maturity period are pre-requisite for improvement in grain yield.

Effect of Tillage and Crop Establishment Methods with Residue Retention on Growth, Yield attributes and Productivity of Wheat under Rice-Wheat Rotation in Typic ustochrept

A field experiment was conducted on sandy loam soil at Crop Research Centre of Sardar Vallabhbhai Patel University of Agriculture & Technology, Meerut, Uttar Pradesh during rabi season (December 2018 to April 2019) in randomised block design with three replications. The treatments comprised of twelve tillage crop establishment methods were used for the experimentation and different observations were recorded during the crop growth period. The results indicated that the growth characters of wheat were significantly higher under wide raised bed residue retention (T9) except narrow raised bed residue retention (T7) and conventional tillage residue incorporation (T11) compared to other treatments. The grain yield, biological yield, harvest Index, yield attributes and grain weight were higher in treatments T9, T7, and T11, respectively. The improvement in grain yield with the tune of 32.09%, 28.14% and 25.49% was under treatments T9, T7 and T11 as compared to T12. It can be concluded that among crop establishment methods, wide raised bed residue retention (T9) found excellent to increase growth, yield attributes and yield for sustainability of wheat crop.

Status of Rice Cultivation and Breeding in Senegal

Rice consumption in Senegal is rapidly increasing due to consumer preferences for rice and urbanization. Despite having a great potential to increase rice production on account of its vast irrigated areas in the Senegal River Valley and the rainfed and upland areas in the Casamance region, Senegal still relies on imported rice to supplement around 44% of rice demand in a year. Rice production in Senegal has been heavily affected by several biological and institutional constraints, including drought, salt, cold, iron toxicity, and diseases and pest. In terms of rice research and development, Senegal has a well-established rice breeding system for varietal development and releasing them to farmers. Since 1994, the country has developed a total of 60 rice varieties in collaboration with international organizations. However, for further improvement of grain yield and quality, this paper proposes the use of Japonica germplasm based on the empirical evidence from the green revolution of IRRI and Korea.

Gains in recurrent selection cycles for grain yield and resistance to head smut in maize

El basidiomiceto <em>Sporisorium reilianum</em> f. sp. <em>zeae</em> infecta al cultivo de maíz y causa importantes pérdidas en regiones donde existen condiciones propicias para el desarrollo de la enfermedad. En este trabajo se evaluó la respuesta a la selección de seis ciclos de selección recurrente de maíces de endospermo blanco y cinco ciclos de maíces de endospermo amarillo para caracteres agronómicos deseables, rendimiento de grano y resistencia al carbón de la espiga. Los diferentes ciclos en las dos poblaciones se obtuvieron siguiendo el método de selección recurrente de familias S1, los cuales fueron evaluados para determinar el avance genético. En un ensayo anexo, las poblaciones fueron inoculadas artificialmente para medir el progreso de la resistencia a la enfermedad y evaluar un nuevo método de inoculación. Se utilizó un diseño experimental de bloques completos al azar con tres repeticiones para el ensayo de rendimiento y dos repeticiones para el ensayo inoculado. Los ciclos evaluados en las dos poblaciones mostraron un incremento en la resistencia de 0.94 y 1.2% ciclo-1, una ganancia genética para rendimiento de grano de 272.9 y 620 kg ha-1 ciclo-1 para la población blanca y amarilla, respectivamente. Los resultados mostraron que la selección recurrente de familias S1 fue eficiente para mejorar el rendimiento de grano y resistencia al carbón de la espiga en ambas poblaciones.

EFFECTS OF HEAVY METAL TOXICITY ON MAZE SEEDLINGS GROWTH TRAITS

Maize is an edible cereal crop that belongs to family Gramineae and use as an energy source for human and animals. In our country the industrial and municipal wastewater has been being used for irrigation purposes that contain heavy metals. These heavy metals affect production of maize crop and soil quality. The purpose of this study was to investigate the affect of different heavy metals on maize growth and to asses more tolerant and more sensitive maize variety. Different concentrations of Mn and Cr (0, 0.25Molar, 0.50Molar) were applies in combined form and individually. Total three replicates were carried out during research. Analysis of variance (ANOVA), Tukey’s rang test (p ≤ 0.05) were applied as statistical tool among treatment means. ANOVA indicated the differences among five different genotypes and 9 different treatments for all parameters were significant. Tukey’s test indicated that higher toxic effect was shown under treatment 0.5M Mn + 0.25M Cr while less toxic effect was observed under treatment 0.50M Mn in maize plant. The genotype 31R88 was more sensitive for metal toxicity because most of 31R88 traits were affected under heavy metal treatments while more tolerant variety was Neelum. Hence the results of our study have suggested that the genotype Neelum may be used for the improvement of grain yield and productivity under heavy metal stress conditions.

DEFECTIVE ENDOSPERM-D1 (Dee-D1) is crucial for endosperm development in hexaploid wheat

Hexaploid wheat (Triticum aestivum L.) is a natural allopolyploid and provides a usable model system to better understand the genetic mechanisms that underlie allopolyploid speciation through the hybrid genome doubling. Here we aimed to identify the contribution of chromosome 1D in the development and evolution of hexaploid wheat. We identified and mapped a novel DEFECTIVE ENDOSPERM–D1 (Dee-D1) locus on 1DL that is involved in the genetic control of endosperm development. The absence of Dee-D1 leads to non-viable grains in distant crosses and alters grain shape, which negatively affects grain number and thousand-grain weight. Dee-D1 can be classified as speciation locus with a positive effect on the function of genes which are involved in endosperm development in hybrid genomes. The presence of Dee-D1 is necessary for the normal development of endosperm, and thus play an important role in the evolution and improvement of grain yield in hexaploid wheat.

Genetic improvement of grain yield and bread-making quality of winter wheat over the past 90 years under the Pannonian Plain conditions

Studies on genetic gains in a historical set of wheat cultivars mostly refer to grain yield and the associated agronomical and physiological traits, while less attention is paid to the improvement of wheat quality. In order to analyze the breeding progress in grain yield and with an emphasis on the main grain and flour properties, twenty-five winter wheat cultivars released in the Southern Pannonian Plain between 1930 and 2015 were grown in three consecutive seasons in Novi Sad (Serbia). The results from this study showed that grain yield increased linearly with an average rate of 45.5 kg ha−1 yr−1, implying that grain yield progress under conditions of the Southern Pannonian Plain have not reached the plateau. Protein and wet gluten content decreased significantly with year of cultivar release, with a bi-linear trend. On the other hand, sedimentation value and gluten index increased in modern wheat cultivars, indicating improved protein quality. Also, the main flour traits related to stronger gluten and high sedimentation value, such as extensograph energy, farinograph resistance and alveograph deformation work, showed improvement with year of cultivar release. Although there were no significant changes in Gluten score, subunits N, 7 + 9 and 5 + 10 at the Glu-A1, Glu-B1 and Glu-D1, respectively, were the most prevalent in modern cultivars. Improvement of the main grain and flour traits could be related with increased frequency of 7 + 9 and 5 + 10 subunits in modern wheat cultivars.

Allelic response of yield component traits to resource availability in spring wheat.

Investigation of resource availability on allele effects for four yield component quantitative trait loci provides guidance for the improvement of grain yield in high and low yielding environments. A greater understanding of grain yield (GY) and yield component traits in spring wheat may increase selection efficiency for improved GY in high and low yielding environments. The objective of this study was to determine allelic response of four yield component quantitative trait loci (QTL) to variable resource levels which were manipulated by varying intraspecific plant competition and seeding density. The four QTL investigated in this study had been previously identified as impacting specific yield components. They included QTn.mst-6B for productive tiller number (PTN), WAPO-A1 for spikelet number per spike (SNS), and QGw.mst-3B and TaGW2-A1 for kernel weight (KWT). Near-isogenic lines for each of the four QTL were grown in multiple locations with three competition (border, no-border and space-planted) and two seeding densities (normal 216 seedsm-2 and low 76 seedsm-2). Allele response at QTn.mst-6B was driven by changes in resource availability, whereas allele response at WAPO-A1 and TaGW2-A1 was relatively unaffected by resource availability. The QTn.mst-6B.1 allele at QTn.mst-6B conferred PTN plasticity resulting in significant GY increases in high resource environments. The gw2-A1 allele at TaGW2-A1 significantly increased KWT, SNS and GPC offering a source of GY improvement without negatively impacting end-use quality. QGw.mst-3B allelic variation did not significantly impact KWT but did significantly impact SPS. Treatment effects in both experiments often resulted in significant positive impacts on GY and yield component traits when resource availability was increased. Results provide guidance for leveraging yield component QTL to improve GY performance in high- and low-yield environments.

Estimation of genetic variability and interrelationship among yield and yield related charactres in mung bean (Vigna radiata (L.) Wilczek)

Forty mung bean (Vigna radiata (L.) Wilczek) genotypes were evaluated for the estimation of genetic variability parameters, correlation coefficient, path analysis, heritability and genetic advance. The genotypes differed significantly for all the characters. Higher GCV and PCV was observed for the number of primary branches per plant and number of pods per plant. High heritability coupled with genetic advance as percent of mean showed by number of primary branches per plant indicating the impact of additive gene expression. The characters days to 50 % flowering, number of pods per cluster, number of seeds per pod and harvest index showed positive and significant correlation along with positive direct effect on grain yield. Therefore, selection based on this component traits would results improvement in grain yield of mung bean.

Correlation and path coefficient analysis for grain yield and its contributing traits in bread wheat (Triticum aestivum L.)

The present experiment was carried out with fifty bread wheat genotypes to estimate correlation coefficients between grain yield and its components and to determine their direct and indirect effects on grain yield using path coefficient analysis. The analysis of variance revealed highly significant differences for all the characters studied. Grain yield per plant had significant and positive correlation with grain weight per main spike, number of grains per main spike, biological yield per plant and harvest index at both the genotypic and phenotypic levels. Days to maturity had significant and positive correlation with grain yield per plant at genotypic level only. The phenotypic and genotypic path coefficient analysis revealed that the biological yield per plant and harvest index exhibited positive and appreciable direct effects on grain yield per plant. Therefore, more emphasis should be given to both these characters for improvement of grain yield in bread wheat through selection programme.

English

Information on genetic progress achieved over time from a breeding program is absolutely essential to develop effective and efficient breeding strategies. Thirty-seven improved lowland sorghum varieties released between 1976 and 2016 and promising advanced lines were evaluated to estimate the genetic progresses made in 40 years of sorghum breeding in Ethiopia. The study was conducted at 2 environments during 2018 cropping seasons in a randomized complete block design with 3 replications. Records taken on grain yield and yield attributes were subjected to statistical analysis. Combined analysis of variance revealed highly significant differences among the genotypes and the test environments for most of the traits, the G×E interaction effects being significant for grain yield. Regression analysis revealed an increase in estimated average annual rate in grain yield potential of 12.2 kg ha-1 year-1 with annual relative genetic change of 0.60% year-1 over the last 40 years of sorghum improvement. Increasing trends along variety release year were also evident for biomass yield, grain yield production per day, biomass production rate and seed growth rate. Stepwise regression analysis revealed that seed growth rate was the most important character, which greatly contributed to the improvement in grain yield. Grain yield was positively correlated with biomass yield, biomass production rate, grain yield production per day, seed growth rate, and thousand seed weight. It is, therefore, strategically advisable that breeding efforts in the future should give due emphasize traits such as seed growth rate.   Key words:  Sorghum, genetic improvement, grain yield.

Genome-wide association study (GWAS) reveals genetic basis of ear-related traits in maize

Maize ear-related traits are important components of grain yield that directly influence maize production. The genetic basis of ear-related traits is still not completely understood, which would be helpful in the improvement of grain yield. In this study, to dissect the genetic basis of ear diameter (ED), ear row number (ERN), and kernel number per row (KNR), a genome-wide association study of maize inbred lines was conducted using the phenotype of the three traits in two environments and the best linear unbiased prediction (BLUP) value. We detected 116 significant loci, i.e., 37, 42, and 37 related to ED, ERN, and KNR, respectively. Among these significant loci, 19 were co-localized when using the traits in two environments and BLUP value. The increase of superior allele number for the 19 co-localized loci was positively correlated with maize grain yield. Further, from the candidate regions of 116 significant loci, 558 genes expressed in maize cob and silk and participated in 71 biological pathways, such as RNA transport, protein export, biosynthesis of amino acids, and starch and sucrose metabolism. Of these candidate genes, some putative functional genes from the co-localized regions were predicted including ts6, pin4, Zm00001d038022, and Zm00001d041584, of which ts6 located in a known major QTL for ERN (named krn1). These results promote the understanding of the genetic basis for these three traits, which contributes to maize grain yield improvement by breeding.

Improvement of Yield, Rust Resistance and Grain Quality Characters in Bread Wheat Cross Sids 12 X Misr 3 تحسین صفات المحصول، مقاومة الأصداء وجودة الحبوب فی هجین قمح الخبز سدس 12 × مصر 3

Bread wheat cross Sids 12 x Misr 3 was studied in F1, F2, F3 and F4 generations to develop promising genotypes for improvement of grain yield, rust resistance and grain quality. The two parents differed significantly for most characters under study showing sufficient variability in F2 and F3 generations to calculate the genetic parameters. The genetic variances indicated important role coupled with moderate to high broad sense heritability for most studied characters in F2 and F3 generations. Both grain filling rate and number of spikes m-2 were the most important characters in selection for high grain yield in F3 generation. Rust resistance in the two parents was controlled by one dominant gene for yellow rust, two dominant genes for leaf rust and two complementary dominant genes for stem rust. Thirty-seven families out of 100 families were superior for grain yield, but the susceptibility of the three rusts eliminated 17 families and only 20 families were resistant or moderately resistant to the three rusts. Five out of the selected 20 families had good grain quality characteristics. In F4 generation, five wheat plants characterized by an adequate resistance to the three rusts and good agronomic characters were selected for further evaluation as F5 lines.

Identification of quantitative trait loci governing early germination and seedling vigor traits related to weed competitive ability in rice

Weed competitive ability (WCA) is vital for the improvement of grain yield under direct-seeded and aerobic rice ecosystems where weeds are a major limiting factor. Early seed germination (ESG) and early seedling vigor (ESV) are the crucial traits for WCA. This study attempted to map the quantitative trait loci (QTLs) and hotspot regions governing ESG and ESV traits. A total of 167 BC1F5 selective introgression lines developed from an early backcross population involving Weed Tolerant Rice 1 (WTR-1) as the recipient parent and Y-134 as the donor parent were phenotyped for ESG and ESV traits. Analysis of variance revealed significant differences in ESG-related traits except for root length and in ESV-related traits except for plant height at 7 days after sowing. A total of 677-high quality single nucleotide polymorphism (SNP) markers were used to analyze the marker-trait association from a 6 K SNP genotyping array. Forty-three QTLs were identified on all chromosomes, except on chromosomes 4 and 8. Thirty QTLs were contributed by a desirable allele from Y-134, whereas 13 QTLs were from WTR-1. Twenty-eight of the identified genetic loci associated with ESG and ESV traits were novel. Two QTL hotspot regions were mapped on chromosomes 11 and 12. The genomic regions of QTL hotspots were fine-tuned and a total of 13 putative candidate genes were discovered on chromosomes 11 and 12 collectively. The mapped QTLs will be useful in advancing the marker aided-selection schemes and breeding programs for the development of rice cultivars with WCA traits.

Nitrogen and α-Ketoglutaric Acid Application Modulate Grain Yield, Aroma, Nutrient Uptake and Physiological Attributes in Fragrant Rice

The present study was conducted to assess the effects of nitrogen (N) and α-ketoglutaric acid application morpho-physiological attributes, aroma regulations and nutrient uptake in fragrant rice. Two fragrant rice cultivars i.e., Yungengyou14 and Yuxiangyouzhan were grown under two N levels i.e., LN: 0 g pot−1 and HN: 1.75 g pot−1 and two α-ketoglutaric acid levels i.e., − A: 0 mg l−1 and + A: 100 mg l−1, applied at 25 ml pot−1. Results showed that the HN − A and HN + A treatments significantly improved the panicle number per pot in Yuxiangyouzhan and Yungengyou14 as compared with LN − A treatment. The HN + A treatment led to substantial improvements in grain yield owing to increased panicle number per pot, grain number per pot, and grain weight. Significant effects of HN + A treatment on agronomic traits such as plant height, leaf dry weight, steam sheath dry weight, panicle dry weight and total dry weight were also noted. Compared with LN − A treatment, the HN − A and HN + A treatments significantly increased the 2-acetyl-1-pyrroline (2AP) contents in grains of Yuxiangyouzhan (7.0% and 15.7%) and Yungengyou14 (47.3% and 43.4%). Under HN + A treatment, the 2AP content in grains as well as the 2AP content in leaves at the heading stage and P5CS activity in leaves increased at the maturity stage as compared with LN − A treatment. Furthermore, the grain 2AP content was significantly and positively related to P5CS activity, as well as Mn and Ca contents in plants. Overall, the application of N and α-ketoglutaric acid modulated the growth, yield, and aroma in fragrant rice, whereas N tends to have more prominent effects on the investigated parameters than α-ketoglutaric acid.

Gains in Genetic Enhancement of Early Maturing Maize Hybrids Developed during Three Breeding Periods under Striga-Infested and Striga-Free Environments

Striga hermonthica is a major maize production constraint in West and Central Africa (WCA). Fifty-four early maturing maize hybrids of three breeding periods: 2008–2011, 2012–2013, 2014–2015, were evaluated under Striga-infested and non-infested environments in WCA. The study aimed at assessing genetic improvement in grain yield of the hybrids, identifying traits associated with yield gain during the breeding periods, and grain yield and stability of the hybrids in Striga infested and non-infested environments. Annual increase in grain yield of 101 kg ha−1 (4.82 %) and 61 kg ha−1 (1.24%) were recorded in Striga-infested and non-infested environments, respectively. The gains in grain yield from period 1 to period 3 under Striga-infested environments were associated with reduced anthesis-silking interval, reduced Striga damage, number of emerged Striga plants, improved ear aspect, and increased ears per plant. Ear aspect, ears per plant, and Striga damage at 8 and 10 weeks after planting (WAP) were significantly correlated with yield in Striga-infested environments, whereas ears per plant and plant and ear aspects had significant correlations with yield in non-infested environments. Hybrids TZdEI 352 × TZEI 355, TZdEI 378 × TZdEI 173, and TZdEI 173 × TZdEI 352 were outstanding in grain yield and stability in Striga-infested environments, whereas TZEI 326 × TZdEI 352, TZEI 495 × ENT 13, and TZdEI 268 × TZdEI 131 were superior in non-stress environments. These hybrids should be further tested extensively and commercialized. Significant genetic gains have been made in breeding for resistance to Striga hermonthica in early maturing maize hybrids.

Appraising the Genetic Architecture of Kernel Traits in Hexaploid Wheat Using GWAS.

Kernel morphology is one of the major yield traits of wheat, the genetic architecture of which is always important in crop breeding. In this study, we performed a genome-wide association study (GWAS) to appraise the genetic architecture of the kernel traits of 319 wheat accessions using 22,905 single nucleotide polymorphism (SNP) markers from a wheat 90K SNP array. As a result, 111 and 104 significant SNPs for Kernel traits were detected using four multi-locus GWAS models (mrMLM, FASTmrMLM, FASTmrEMMA, and pLARmEB) and three single-locus models (FarmCPU, MLM, and MLMM), respectively. Among the 111 SNPs detected by the multi-locus models, 24 SNPs were simultaneously detected across multiple models, including seven for kernel length, six for kernel width, six for kernels per spike, and five for thousand kernel weight. Interestingly, the five most stable SNPs (RAC875_29540_391, Kukri_07961_503, tplb0034e07_1581, BS00074341_51, and BobWhite_049_3064) were simultaneously detected by at least three multi-locus models. Integrating these newly developed multi-locus GWAS models to unravel the genetic architecture of kernel traits, the mrMLM approach detected the maximum number of SNPs. Furthermore, a total of 41 putative candidate genes were predicted to likely be involved in the genetic architecture underlining kernel traits. These findings can facilitate a better understanding of the complex genetic mechanisms of kernel traits and may lead to the genetic improvement of grain yield in wheat.