Main-effect QTL, epistatic effects and their interactions with environment are important genetic components of quantitativetraits. In this study, we analyzed the QTL, epistatic effects and QTL by environment interacti...Main-effect QTL, epistatic effects and their interactions with environment are important genetic components of quantitativetraits. In this study, we analyzed the QTL, epistatic effects and QTL by environment interactions (QE) underlying plantheight and heading date, using a doubled-haploid ( DH) population consisting of 190 lines from the cross between anindica parent Zhenshan 97 and a japonica parent Wuyujing 2, and tested in two-year replicated field trials. A geneticlinkage map with 179 SSR (simple sequence repeat) marker loci was constructed. A mixed linear model approach wasapplied to detect QTL, digenic interactions and QEs for the two traits. In total, 20 main-effect QTLs, 9 digenic interactionsinvolving 18 loci, and 5 QTL by environment interactions were found to be responsible for the two traits. No interactionswere detected between the digenic interaction and environment. The amounts of variations explained by QTLs of maineffect were 53.9% for plant height and 57.8% for heading date, larger than that explained by epistasis and QEs. However,the epistasis and QE interactions sometimes accounted for a significant part of phenotypic variation and should not bedisregarded.展开更多
The dense and erect panicle (EP) genotype conferred by DEP1 has been widely used in the breeding of high-yield Chinese japonica rice varieties.However,the breeding value of the EP genotype has rarely been determined a...The dense and erect panicle (EP) genotype conferred by DEP1 has been widely used in the breeding of high-yield Chinese japonica rice varieties.However,the breeding value of the EP genotype has rarely been determined at the plant population level.Therefore,the effects of the interaction of EP genotype and the environment at different locations and times on rice yield and its various components were investigated in this study.Two sets of near-isogenic lines (NILs)of EP and non-EP (NEP) genotypes with Liaojing 5 (LG5) and Akitakomachi (AKI) backgrounds were grown in the field in 2016 and 2017 in Shenyang,China,and Kyoto,Japan.In 2018,these sets were grown only in Kyoto,Japan.The average yields of the EP and NEP genotypes were 6.67 and 6.13 t ha^(-1)for the AKI background,and 6.66 and 6.58 t ha^(-1)for the LG5 background,respectively.The EP genotype positively affected panicle number (PN) and grain number per square meter (GNPM),mostly resulting in a positive effect on harvest index (HI).In contrast,the EP genotype exerted a negative effect on thousand-grain weight (KGW).The ratio of the performance of the EP genotype relative to the NEP genotype in terms of yield and total biomass correlated positively with mean daily solar radiation during a 40-day period around heading.These results indicate that the effectiveness of the EP genotype depends on the availability of solar radiation,and the effect of this genotype is consistently positive for sink formation,conditional in terms of source capacity,and positive in a high-radiation environment.展开更多
To explore the effect of genotype and genotype x environment interaction on Fe concentration in rice grains, Fe concentrations of 10 genotypes were analyzed across eight paddy field environments during 2007-2008 using...To explore the effect of genotype and genotype x environment interaction on Fe concentration in rice grains, Fe concentrations of 10 genotypes were analyzed across eight paddy field environments during 2007-2008 using the AMMI-biplot method. Experiments were conducted using a randomized completely block design with three replications in eight environments. Results indicated that environment （E）, genotype （G） and genotype x environment interaction （GE） significantly affected Fe concentration in rice grains. Environment explained 74.43 % of total （G＋E＋GE） variation, whereas G and GE captured 5.60% and 19.67%, respectively. Rice genotype Barumun was desirable in terms of the highest ability and stability for Fe concentration in rice grains. Environment in genotype Cilongok was the best representative of the overall environments and the most powerful to discriminate rice genotypes.展开更多
Cassava is an important starchy root crop and a major staple for more than 70 million people in Nigeria. New yellow-fleshed genotypes are being developed to combat vitamin A deficiency. Trials of 18 yellow-fleshed gen...Cassava is an important starchy root crop and a major staple for more than 70 million people in Nigeria. New yellow-fleshed genotypes are being developed to combat vitamin A deficiency. Trials of 18 yellow-fleshed genotypes and two officially released white-fleshed clones, used as checks for 2008/2009 and 2009/2010 seasons in five major cassava growing agroecological zones of Nigeria. The trial locations were Ikenne （humid forest）, Ibadan （forest-savanna transition）, Ubiaja （subhumid forest）, Mokwa （southern Guinea savanna） and Zaria （northern Guinea savanna）. At each location, the trial was established in a randomized complete block design with four replications. The objective of the study was to assess genotype performance and genotype ~ environment interaction for total carotene concentration （TCC）, total carotene content per root （TC-R）, and total carotene content per plant （TC-P）. Significant differences （P 〈 0.001） among genotypes, environments and genotype x environment interaction for all the traits evaluated were observed. For TCC, TC-R and TC-P, the best genotypes across the 10 environments were TMS I051601, TMS 1050311, and TMS 1050998. Variation among genotypes accounted for most of the Total Sum of Squares for TCC （67.9%）, TC-R （39.0%） and TC-P （35.9%）. These characteristics of total carotene were also highly correlated. This study revealed that cassava with total carotene concentration can be assessed using either the TCC, or the TC-R, or the TC-P.展开更多
Chalkiness is an unpleasant trait for rice con-sumer,which is known to be controlled geneti-cally and affected by environment during grainmaturing.We used the model of Additive Main
A crossbreeding program was established in 2019 to address the declining Crassostrea gigas harvests caused by Pacific Oyster Mortality Syndrome(POMS).As a part of the program,this study was performed to estimate the g...A crossbreeding program was established in 2019 to address the declining Crassostrea gigas harvests caused by Pacific Oyster Mortality Syndrome(POMS).As a part of the program,this study was performed to estimate the genetic structure underlying phenotypic variation.Fifteen complete diallel crossings of C.gigas and C.angulata,comprising 60 full-sib families,were used to evaluate the general combining ability(GCA)and specific combining ability(SCA),as well as genotype and environment interactions for shell height(SH),summer survival(SS),and thermal tolerance(TT)of reciprocal hybrids GA(C.gigas♀×C.angulata♂)and AG(C.angulata♀×C.gigas♂)grown in Rongcheng and Rushan,Shandong Province,China.The results suggested that heterosis of the reciprocal hybrids was evident for SH,SS,and TT.The hybrid GA had larger heterosis than AG in both testing environments,and can be a potential donor in the breeding program.The male C.gigas had better GCA for SH in Rongcheng,whereas male C.angulata was a good general combiner for SS and TT in both Rongcheng and Rushan.The estimate of SCA was much higher than GCA for SH and lower than GCA for TT.To harness both additive and non-additive genetic effects,combination breed-ing could be taken to develop hybrid varieties possessing both thermal tolerance and fast-growing traits.The positive correlations between SH and TT suggested that these traits could be improved simultaneously.The significant G×E interactions demonstrated the importance to undertake site-specific breeding programs in different environments.Overall,this study can provide essential information for developing crossbreeding strategies for the oyster farming industry.展开更多
Rice,as a primary commodity,needs to be increased in production while facing the sustainability challenges of limited land,water resources,and climate change.The demand for rice productivity was not enough to rely onl...Rice,as a primary commodity,needs to be increased in production while facing the sustainability challenges of limited land,water resources,and climate change.The demand for rice productivity was not enough to rely only on the fertile fields’ability;it is necessary to consider the rainfed land potential.Cultivation in rainfed land involves biophysical pressure,lowproduction,and limited access to superior varieties.Participatory rice breeding aimed to identify farmers’trait preferences and develop acceptable lines.A bottom-up approach involved 203 farmers from four rainfed fields in Indonesia,i.e.,Semarang-Central Java,Kulon Progo-Yogyakarta,Tabanan-Bali,andGunungkidul-Yogyakarta.The experiment on February-June 2024 tested six lines(G2,G3,G4,G5,G9,and G10)and four varieties(Situ Bagendit,Gamagora7,Inpari IRNutri Zinc,and Inpago12 Agritan).Farmers’involvement in evaluating the suitability of genotypes involved using Multidimensional Scaling and Importance-Performance Analysis.Breeders added comprehensive analysis in the growing environment with Genotype Environment Interaction,and key attributes of leverage analysis from farmers must be considered.Genotype performance in the Multidimensional Scaling feasibility indicated that yield primary determinants were panicle type,disease resistance,leaf characteristics,and environmental resilience.Importance Performance Analysis verified that G3,G9,G2,and G4 had a preference at the farm level.Genotype Environment Interaction reveals that G3,G4,and G2 were ideal lines with high potential yields,suitability,and adaptability on rainfed land.Participatory rice breeding in rainfed land integrates farmers’assessments and breeders’observations to realize the most preferred genotypes according to the challenges for sustainable agriculture.展开更多
To improve multi-environmental trial(MET)analysis,a compound method—which combines factor analytic(FA)model with additive main effect and multiplicative interaction(AMMI)and genotype main effect plus genotype-by-envi...To improve multi-environmental trial(MET)analysis,a compound method—which combines factor analytic(FA)model with additive main effect and multiplicative interaction(AMMI)and genotype main effect plus genotype-by-environment interaction(GGE)biplot—was conducted in this study.The diameter at breast height of 36 open-pollinated(OP)families of Pinus taeda at six sites in South China was used as a raw dataset.The best linear unbiased prediction(BLUP)data of all individual trees in each site was obtained by fitting the spatial effects with the FA method from raw data.The raw data and BLUP data were analyzed and compared by using the AMMI and GGE biplot.BLUP results showed that the six sites were heterogeneous and spatial variation could be effectively fitted by spatial analysis with the FA method.AMMI analysis identified that two datasets had highly significant effects on the site,family,and their interactions,while BLUP data had a smaller residual error,but higher variation explaining ability and more credible stability than raw data.GGE biplot results revealed that raw data and BLUP data had different results in mega-environment delineation,test-environment evaluation,and genotype evaluation.In addition,BLUP data results were more reasonable due to the stronger analytical ability of the first two principal components.Our study suggests that the compound method combing the FA method with the AMMI and GGE biplot could improve the analysis result of MET data in Pinus teada as it was more reliable than direct AMMI and GGE biplot analysis on raw data.展开更多
Identification and deployment of high-yielding and stress-tolerant maize hybrids adapted to stress-prone agro-ecologies is important for improving the food security and livelihoods of smallholder farmers in eastern Af...Identification and deployment of high-yielding and stress-tolerant maize hybrids adapted to stress-prone agro-ecologies is important for improving the food security and livelihoods of smallholder farmers in eastern Africa.The objectives of this study were to(i)assess the performance of maize hybrids under well-watered and drought stress conditions;(ii)evaluate grain yield stability of 65 intermediate-maturing and 55 early-maturing hybrids in 24 well-watered locations and seven drought stress locations;and(iii)identify representative and/or discriminative testing locations for increasing genetic gains for the target traits.There were significant differences for grain yield among early-and intermediatematuring hybrids tested under well-watered and drought stress environments.Among the early-maturing hybrids,the top 10 hybrids produced 46.8%–73.9%and 31.2%–42.1%higher mean grain yields than the best commercial check under drought and well-watered conditions,respectively.Among the intermediate-maturing hybrids,the top 10 hybrids produced 25.2%–47.7%and 8.5%–13.5%higher grain yield than commercial checks under drought stress and well-watered conditions,respectively,suggesting improvement in the levels of drought tolerance in both early-and intermediate-maturing hybrids.GGE biplot analysis and a bi-segmented regression linear method identified specific early-maturing and intermediate-maturing hybrids that performed well under both well-watered and drought stress conditions.These hybrids could be recommended for commercial production in eastern Africa.Kakamega in Kenya was found to be the most representative and highly discriminating site among well-watered testing locations,while Kabuku in Tanzania was the least representative of test locations.For testing under drought stress conditions,Kiboko in Kenya was identified as the most representative location.This information could be useful for allocating resources and streamlining CIMMYT maize hybrid testing in eastern Africa.展开更多
Crop seeds are important sources of protein, oil, and carbohydrates for food, animal feeds, and industrial products. Recently, much attention has been paid to quality and functional properties of crop seeds. However, ...Crop seeds are important sources of protein, oil, and carbohydrates for food, animal feeds, and industrial products. Recently, much attention has been paid to quality and functional properties of crop seeds. However, seed traits possess some distinct genetic characteristics in comparison with plant traits, which increase the difficulty of genetically improving these traits. In this study, diallel analysis for seed models with genotype by environment interaction （GE） effect was applied to estimate the variance-covariance components of seed traits. Mixed linear model approaches were used to estimate the genetic covariances between pair-wise seed and plant traits. The breeding values （BV） were divided into two categories for the seed models. The first category of BV was defined as the combination of direct additive, cytoplasmic, and maternal additive effects, which should be utilized for selecting stable cultivars over multi-environments. The three genetic effects, together with their GE interaction, were included in the second category of BV for selecting special lines to be grown in specific ecosystems. Accordingly, two types of selection indices for seed traits, i.e., general selection index and interaction selection index, were developed and constructed on the first and the second category BV, respectively. These proposed selection indices can be applied to solve the difficult task of simultaneously improving multiple seed traits in various environments. Data of crop seeds with regard to four seed traits and four yield traits based on the modified diallel crosses in Upland cotton （Gossypium hirsutum L.） were used as an example for demonstrating the proposed methodology.展开更多
Background Globally,the cultivation of cotton is constrained by its tendency for extended periods of growth.Early maturity plays a potential role in rainfed-based multiple cropping system especially in the current era...Background Globally,the cultivation of cotton is constrained by its tendency for extended periods of growth.Early maturity plays a potential role in rainfed-based multiple cropping system especially in the current era of climate change.In the current study,a set of 20 diverse Gossypium hirsutum genotypes were evaluated in two crop seasons with three planting densities and assessed for 11 morphological traits related to early maturity.The study aimed to identify genotype(s)that mature rapidly and accomplish well under diverse environmental conditions based on the two robust multivariate techniques called multi-trait stability index(MTSI)and multi-trait genotype-ideotype distance index(MGIDI).Results MTSI analysis revealed that out of the 20 genotypes,three genotypes,viz.,NNDC-30,A-2,and S-32 accomplished well in terms of early maturity traits in two seasons.Furthermore,three genotypes were selected using MGIDI method for each planting densities with a selection intensity of 15%.The strengths and weaknesses of the genotypes selected based on MGIDI method highlighted that the breeders could focus on developing early-maturing genotypes with specific traits such as days to first flower and boll opening.The selected genotypes exhibited positive genetic gains for traits related to earliness and a successful harvest during the first and second pickings.However,there were negative gains for traits related to flowering and boll opening.Conclusion The study identified three genotypes exhibiting early maturity and accomplished well under different planting densities.The multivariate methods(MTSI and MGIDI)serve as novel approaches for selecting desired genotypes in plant breeding programs,especially across various growing environments.These methods offer exclusive benefits and can easily construe and minimize multicollinearity issues.展开更多
Background:Genotype×environment interaction(GEI)slows genetic gains and complicates selection decisions in plant breeding programs.Forage breeding program seed sales often encompass large geographic regions to wh...Background:Genotype×environment interaction(GEI)slows genetic gains and complicates selection decisions in plant breeding programs.Forage breeding program seed sales often encompass large geographic regions to which the cultivars may not be adapted.An understanding of the extent of GEI in perennial,cool-season forage grasses will facilitate improved selection decisions and end-use in areas with harsh winters.Methods:We evaluated the dry matter yield of nine meadow brome(Bromus biebersteinii Roemer&J.A.Schultes),nine orchardgrass(Dactylis glomerata L.),seven tall fescue(Lolium arundinaceum(Schreb.)Darbysh.),and 10 timothy(Phleum pratense L.)cultivars or breeding populations at seven high latitude and/or elevation locations in Canada and the United States from 2019 to 2021.Results:For each of the species,we found significant differences among the genotypes for dry matter yield across environments and found significant levels of GEI.Using site regression analysis and GGE biplot visualizations,we then characterized the extent of the interactions in each species.Except for tall fescue,there was little evidence for the broad adaptation of genotypes across locations.Conclusions:This research adds further evidence to the limitations of perennial,forage breeding programs to develop widely adapted cultivars and the need to maintain regional breeding efforts.展开更多
The present study focused on evaluating the agronomic performance, stability, and anthracnose resistance of common bean lines derived through Marker-Assisted Backcrossing in Uganda. Eight marker-assisted selection (MA...The present study focused on evaluating the agronomic performance, stability, and anthracnose resistance of common bean lines derived through Marker-Assisted Backcrossing in Uganda. Eight marker-assisted selection (MAS) backcross-derived bush bean lines with red seed types, alongside two checks, were evaluated in a randomized complete block design replicated two times in five locations for three consecutive crop-growing seasons in 2021 and 2022. The study aimed to identify lines with both high stable yields and enhanced resistance to anthracnose disease for potential release and utilization in future bean varietal development in Uganda. Agronomic traits, including days to 50% flowering, days to 90% physiological maturity, seed yield, seed yield components, and anthracnose disease reaction under natural infestation were assessed. The response to anthracnose disease was further assessed using six isolates of Colletotrichum lindemuthianum representing six different races. Results indicated that the agronomic performances of the MAS backcross-derived bush bean lines were statistically comparable to the recurrent parent NABE14. Specifically, six lines exhibited statistically equal to or higher performance than NABE14 in terms of seed yield, total number of seeds and number of pods per plant. The combined analysis of variance for seed yield showed significant (p Co-4<sup>2</sup> and Co-5 anthracnose resistance genes in the derived line. In conclusion, UGKT-B157-4, identified as the best-performing and stable genotype, demonstrates promise for release and use in future bean varietal development in Uganda, offering a combination of high yields and enhanced anthracnose disease resistance. The study provides valuable insights into the potential of Marker-Assisted Backcrossing in improving common bean varieties in the region.展开更多
Forty-seven spring wheat Triticumaestivum cultivars and advanced lines from spring-sown spring wheat regions, at twelve locations in 1998 and 1999, were used to investigate pasting properties of Chinese spring wheats....Forty-seven spring wheat Triticumaestivum cultivars and advanced lines from spring-sown spring wheat regions, at twelve locations in 1998 and 1999, were used to investigate pasting properties of Chinese spring wheats. Starch pasting properties were closely associated with noodle quality. Significant differences were observed for all pasting characteristics. Samples collected from Harbin, Shenyang, Beijing, Ba-meng, Yongning, and Urumqi had better pasting quality than those from other locations. Genotype, environment, and genotype by environment interaction had large effects on all pasting characteristics. Significant correlations among pasting characteristics were observed and peak viscosity was considered the most important pasting characteristics.展开更多
Genetic analysis of rolled leaf is important to rice ideotype breeding. To detect loci controlling rolled leaf of japonica restorer lines, SSR marker genotypes and phenotypes of flag leaf rolling index （LRI） were in...Genetic analysis of rolled leaf is important to rice ideotype breeding. To detect loci controlling rolled leaf of japonica restorer lines, SSR marker genotypes and phenotypes of flag leaf rolling index （LRI） were investigated in Xiushui 79 （P1, a japonica rice variety）, C Bao （P2, a japonica restorer line） and 254 recombinant inbred lines derived from the cross between P1 and P2 , and in two environments. A genetic map of this cross was constructed, QTLs for LRI were detected and their interactions with environments were analyzed. Among 818 pairs of SSR primers, 90 primers showed polymorphism between P1 and P2, and 12 markers showed highly significant correlation with LRI in both environments based on single marker regression analysis. The genetic map containing 74 information loci has a total distance of 744.6 cM, with an average of 10.1 cM between two adjacent loci. Three QTLs （qRL-1, qRL-7 and qRL-8-1） were detected with two softwares： WinQTLCart 2.5 and QTLNetwork2.0. qRL-8-1 was a new locus, accounting for 15.5% and 12.8% of phenotypic variations in the two environments, respectively. The phenotypic variation explained by additive effect was 6.6%. No interaction was found between qRL-8-1 genotype and environments.展开更多
Plant phenotypes are infl uenced by genetic and environmental factors.In this study,the growth traits of 43 one-year-old poplar clones grown at diff erent sites in northeast China(Dongling State-owned Forest Protectio...Plant phenotypes are infl uenced by genetic and environmental factors.In this study,the growth traits of 43 one-year-old poplar clones grown at diff erent sites in northeast China(Dongling State-owned Forest Protection Center,DL;Baicheng State-owned forest farm,BC;and Cuohai Forest farm,CH)were evaluated and analyzed across clones and sites.Results show signifi cant diff erences in height and base diameter among sites and clones.Phenotypic and genetic variation coeffi cients ranged from 49.59%(BC)to 58.39%(DL)and from 49.33%(BC)to 58.06%(DL),respectively.Additive main eff ects and multiplicative interaction(AMMI)analysis showed that the eff ects of genotype,environment,and genotype×environment interaction were signifi cantly diff erent.Genetic variation was the main source of variation,accounting for 48.6%.AMMI biplot showed that clone 30 had high and stable yields at the three sites.From an evaluation of multiple traits and GGE biplot that clone 2,clone 30 and clone 25 had higher yield than the other clones at DL,CH and BC,respectively.These clones will provide material for forest regeneration in northeast China.展开更多
The effects of genetic and environmental factors on Pinus koraiensis growth were studied based on a35 year-old progeny trial composed of open-pollinated offspring of twenty-one plus trees.Height,DBH and volume of the ...The effects of genetic and environmental factors on Pinus koraiensis growth were studied based on a35 year-old progeny trial composed of open-pollinated offspring of twenty-one plus trees.Height,DBH and volume of the offspring was analyzed using restricted maximum likelihood/best linear unbiased prediction in mixed model analysis.Significant site and family effects on the three traits were observed.The distinct growth of offspring by site with disparate climates corroborated the importance of planting species in suitable conditions.Growth differences by family was significant,emphasizing the importance of identifying families with either superior or inferior performance.The parental ranking was assigned in the sites,inferring the breeding value of each plus tree.The estimates of individual heritability(h_(i)^(2))of height,DBH and volume growth were 0.169-0.645,0.108-0.331 and 0.129-0.343 respectively,with higher h_(i)^(2) of the height than DBH on each site.Coefficient of variance of genetic effect was higher with DBH in some cases,indicating the scope for selection is larger for this trait despite the lower heritability compared to height.For the variation between families in terms of the performance stability across sites,consideration of the genotype by environment interaction is required in selecting materials to be used in reforestation with Korean pine.A few families with either superior or inferior performance retained their parental ranking for at least a decade.Other families with increased growth on a particular site were identified,indicating their high breeding value and low stability.Differences in the genetic performance of the families by site requires delineation of the breeding region of the species.展开更多
Cassava productivity is hampered by pests and diseases including cassava<span style="font-family:;" "=""><span style="font-family:Verdana;"> mosaic disease (CMD) and cass...Cassava productivity is hampered by pests and diseases including cassava<span style="font-family:;" "=""><span style="font-family:Verdana;"> mosaic disease (CMD) and cassava brown streak disease (CBSD).</span><b> </b><span style="font-family:Verdana;">The main ob</span><span style="font-family:Verdana;">jective of this study was to identify stable superior genotypes that combine</span><span style="font-family:Verdana;"> dis</span><span style="font-family:Verdana;">ease resistance and high yield. Sixteen cassava genotypes were planted in a</span> <span style="font-family:Verdana;">randomized complete block design with three replications for six planting </span><span style="font-family:Verdana;">seasons (years) at five sites in Tanzania. The genotypes were assessed using the additive main effect and multiplicative interaction (AMMI) analysis, and highly significant (</span></span><span style="font-family:Verdana;">P </span><span style="font-family:Verdana;">< 0.001) effects of genotype, environment, and genotype-</span><span style="font-family:;" "=""><span style="font-family:Verdana;">by-environment (</span><i><span style="font-family:Verdana;">G</span><sup><span style="font-family:Verdana;">*</span></sup><span style="font-family:Verdana;">E</span></i><span style="font-family:Verdana;">) interactions were observed for all traits studied. Per</span><span style="font-family:Verdana;">cent sum of squares (SS) due to environment (12.66% - 85.23%) was the</span><span style="font-family:Verdana;"> highest followed by </span><i><span style="font-family:Verdana;">G</span><sup><span style="font-family:Verdana;">*</span></sup><span style="font-family:Verdana;">E</span></i><span style="font-family:Verdana;"> (14.12% - 39.56%) for CMD foliar symptoms, root weight and dry matter. On the other hand, % SS due to genotype (52.14% - 69.14%) </span><span><span style="font-family:Verdana;">was highest followed by </span><i><span style="font-family:Verdana;">G</span><sup><span style="font-family:Verdana;">*</span></sup><span style="font-family:Verdana;">E</span></i><span style="font-family:Verdana;"> (26.14% - 35.91%) for CBSD foliar and root</span></span><span style="font-family:Verdana;"> symptoms indicating that the environment and </span><i><span style="font-family:Verdana;">G</span><sup><span style="font-family:Verdana;">*</span></sup><span style="font-family:Verdana;">E</span></i><span style="font-family:Verdana;"> greatly influenced trait expression. The most stable genotypes which combined disease resistance and high yield were NDL 2003/31 and NDL 2003/111. The findings of this study will give impetus for the release of new cassava varieties that are not only high yielding but are also dually resistant to both CMD and CBSD in different locations and sites.</span></span>展开更多
Transgene insert location in the genome through different methods is random. Thus, alterations in the expression of desired trait may occur, as well as alterations in the expression of other characteristics of recepto...Transgene insert location in the genome through different methods is random. Thus, alterations in the expression of desired trait may occur, as well as alterations in the expression of other characteristics of receptor plant. The purpose of this study was to compare Bt transgenic maize hybrids and the respective conventional isogenic hybrid in relation to adaptability and phenotypic stability. Field trails were set up in four locations of Minas Gerais, Brazil (Campo do Meio, Lavras, Madre de Deus and Paragua?u). A randomized complete block design was used, with three replications, and the treatment structure was a factorial 6 × 2, with six hybrids in the transgenic and conventional versions. Plant and ear height and grain yield were evaluated. To estimate stability, the Anicchiarico, Wricke and AMMI methodologies were used. Grain yield and ear height of the transgenic hybrids and their respective conventional isogenic hybrid did not differ. There are differences in the phenotypic stability between transgenic hybrids with Bt technology and their counterpart conventional isogenic hybrid.展开更多
Identifying mechanisms and pathways involved in gene–environment interplay and phenotypic plasticity is a long-standing challenge.It is highly desirable to establish an integrated framework with an environmental dime...Identifying mechanisms and pathways involved in gene–environment interplay and phenotypic plasticity is a long-standing challenge.It is highly desirable to establish an integrated framework with an environmental dimension for complex trait dissection and prediction.A critical step is to identify an environmental index that is both biologically relevant and estimable for new environments.With extensive field-observed complex traits,environmental profiles,and genome-wide single nucleotide polymorphisms for three major crops(maize,wheat,and oat),we demonstrated that identifying such an environmental index(i.e.,a combination of environmental parameter and growth window)enables genome-wide association studies and genomic selection of complex traits to be conducted with an explicit environmental dimension.Interestingly,genes identified for two reaction-norm parameters(i.e.,intercept and slope)derived from flowering time values along the environmental index were less colocalized for a diverse maize panel than for wheat and oat breeding panels,agreeing with the different diversity levels and genetic constitutions of the panels.In addition,we showcased the usefulness of this framework for systematically forecasting the performance of diverse germplasm panels in new environments.This general framework and the companion CERIS-JGRA analytical package should facilitate biologically informed dissection of complex traits,enhanced performance prediction in breeding for future climates,and coordinated efforts to enrich our understanding of mechanisms underlying phenotypic variation.展开更多
基金We gratefully acknowledge Prof.Zhu Jun for kind pro-V1sion of software QTLMapper 1.0.The work was in part supported by the National High Tech R&D Pro-gram of China(863 Program)the National Natural Sci-ence Foundation of China and the National Program on Key Basic Research Project of China(973 Program).
文摘Main-effect QTL, epistatic effects and their interactions with environment are important genetic components of quantitativetraits. In this study, we analyzed the QTL, epistatic effects and QTL by environment interactions (QE) underlying plantheight and heading date, using a doubled-haploid ( DH) population consisting of 190 lines from the cross between anindica parent Zhenshan 97 and a japonica parent Wuyujing 2, and tested in two-year replicated field trials. A geneticlinkage map with 179 SSR (simple sequence repeat) marker loci was constructed. A mixed linear model approach wasapplied to detect QTL, digenic interactions and QEs for the two traits. In total, 20 main-effect QTLs, 9 digenic interactionsinvolving 18 loci, and 5 QTL by environment interactions were found to be responsible for the two traits. No interactionswere detected between the digenic interaction and environment. The amounts of variations explained by QTLs of maineffect were 53.9% for plant height and 57.8% for heading date, larger than that explained by epistasis and QEs. However,the epistasis and QE interactions sometimes accounted for a significant part of phenotypic variation and should not bedisregarded.
基金supported by the Joint Funds of the National Natural Science Foundation of China(U1708231 and JSPS KAKENHI,26292013)。
文摘The dense and erect panicle (EP) genotype conferred by DEP1 has been widely used in the breeding of high-yield Chinese japonica rice varieties.However,the breeding value of the EP genotype has rarely been determined at the plant population level.Therefore,the effects of the interaction of EP genotype and the environment at different locations and times on rice yield and its various components were investigated in this study.Two sets of near-isogenic lines (NILs)of EP and non-EP (NEP) genotypes with Liaojing 5 (LG5) and Akitakomachi (AKI) backgrounds were grown in the field in 2016 and 2017 in Shenyang,China,and Kyoto,Japan.In 2018,these sets were grown only in Kyoto,Japan.The average yields of the EP and NEP genotypes were 6.67 and 6.13 t ha^(-1)for the AKI background,and 6.66 and 6.58 t ha^(-1)for the LG5 background,respectively.The EP genotype positively affected panicle number (PN) and grain number per square meter (GNPM),mostly resulting in a positive effect on harvest index (HI).In contrast,the EP genotype exerted a negative effect on thousand-grain weight (KGW).The ratio of the performance of the EP genotype relative to the NEP genotype in terms of yield and total biomass correlated positively with mean daily solar radiation during a 40-day period around heading.These results indicate that the effectiveness of the EP genotype depends on the availability of solar radiation,and the effect of this genotype is consistently positive for sink formation,conditional in terms of source capacity,and positive in a high-radiation environment.
文摘To explore the effect of genotype and genotype x environment interaction on Fe concentration in rice grains, Fe concentrations of 10 genotypes were analyzed across eight paddy field environments during 2007-2008 using the AMMI-biplot method. Experiments were conducted using a randomized completely block design with three replications in eight environments. Results indicated that environment （E）, genotype （G） and genotype x environment interaction （GE） significantly affected Fe concentration in rice grains. Environment explained 74.43 % of total （G＋E＋GE） variation, whereas G and GE captured 5.60% and 19.67%, respectively. Rice genotype Barumun was desirable in terms of the highest ability and stability for Fe concentration in rice grains. Environment in genotype Cilongok was the best representative of the overall environments and the most powerful to discriminate rice genotypes.
文摘Cassava is an important starchy root crop and a major staple for more than 70 million people in Nigeria. New yellow-fleshed genotypes are being developed to combat vitamin A deficiency. Trials of 18 yellow-fleshed genotypes and two officially released white-fleshed clones, used as checks for 2008/2009 and 2009/2010 seasons in five major cassava growing agroecological zones of Nigeria. The trial locations were Ikenne （humid forest）, Ibadan （forest-savanna transition）, Ubiaja （subhumid forest）, Mokwa （southern Guinea savanna） and Zaria （northern Guinea savanna）. At each location, the trial was established in a randomized complete block design with four replications. The objective of the study was to assess genotype performance and genotype ~ environment interaction for total carotene concentration （TCC）, total carotene content per root （TC-R）, and total carotene content per plant （TC-P）. Significant differences （P 〈 0.001） among genotypes, environments and genotype x environment interaction for all the traits evaluated were observed. For TCC, TC-R and TC-P, the best genotypes across the 10 environments were TMS I051601, TMS 1050311, and TMS 1050998. Variation among genotypes accounted for most of the Total Sum of Squares for TCC （67.9%）, TC-R （39.0%） and TC-P （35.9%）. These characteristics of total carotene were also highly correlated. This study revealed that cassava with total carotene concentration can be assessed using either the TCC, or the TC-R, or the TC-P.
文摘Chalkiness is an unpleasant trait for rice con-sumer,which is known to be controlled geneti-cally and affected by environment during grainmaturing.We used the model of Additive Main
基金founded by the National Key R&D Program of China(No.2022YFD2400305)the Earmarked Fund for Agriculture Seed Improvement Project of Shandong Province(Nos.2022LZGCQY010,2021LZGC027 and 2021ZLGX03)the China Agriculture Research System Project(No.CARS-49)。
文摘A crossbreeding program was established in 2019 to address the declining Crassostrea gigas harvests caused by Pacific Oyster Mortality Syndrome(POMS).As a part of the program,this study was performed to estimate the genetic structure underlying phenotypic variation.Fifteen complete diallel crossings of C.gigas and C.angulata,comprising 60 full-sib families,were used to evaluate the general combining ability(GCA)and specific combining ability(SCA),as well as genotype and environment interactions for shell height(SH),summer survival(SS),and thermal tolerance(TT)of reciprocal hybrids GA(C.gigas♀×C.angulata♂)and AG(C.angulata♀×C.gigas♂)grown in Rongcheng and Rushan,Shandong Province,China.The results suggested that heterosis of the reciprocal hybrids was evident for SH,SS,and TT.The hybrid GA had larger heterosis than AG in both testing environments,and can be a potential donor in the breeding program.The male C.gigas had better GCA for SH in Rongcheng,whereas male C.angulata was a good general combiner for SS and TT in both Rongcheng and Rushan.The estimate of SCA was much higher than GCA for SH and lower than GCA for TT.To harness both additive and non-additive genetic effects,combination breed-ing could be taken to develop hybrid varieties possessing both thermal tolerance and fast-growing traits.The positive correlations between SH and TT suggested that these traits could be improved simultaneously.The significant G×E interactions demonstrated the importance to undertake site-specific breeding programs in different environments.Overall,this study can provide essential information for developing crossbreeding strategies for the oyster farming industry.
基金funded by the Research Organization for Agricultural and Food,the National Research and Innovation Agency(BRIN),and Universitas Gadjah Mada.
文摘Rice,as a primary commodity,needs to be increased in production while facing the sustainability challenges of limited land,water resources,and climate change.The demand for rice productivity was not enough to rely only on the fertile fields’ability;it is necessary to consider the rainfed land potential.Cultivation in rainfed land involves biophysical pressure,lowproduction,and limited access to superior varieties.Participatory rice breeding aimed to identify farmers’trait preferences and develop acceptable lines.A bottom-up approach involved 203 farmers from four rainfed fields in Indonesia,i.e.,Semarang-Central Java,Kulon Progo-Yogyakarta,Tabanan-Bali,andGunungkidul-Yogyakarta.The experiment on February-June 2024 tested six lines(G2,G3,G4,G5,G9,and G10)and four varieties(Situ Bagendit,Gamagora7,Inpari IRNutri Zinc,and Inpago12 Agritan).Farmers’involvement in evaluating the suitability of genotypes involved using Multidimensional Scaling and Importance-Performance Analysis.Breeders added comprehensive analysis in the growing environment with Genotype Environment Interaction,and key attributes of leverage analysis from farmers must be considered.Genotype performance in the Multidimensional Scaling feasibility indicated that yield primary determinants were panicle type,disease resistance,leaf characteristics,and environmental resilience.Importance Performance Analysis verified that G3,G9,G2,and G4 had a preference at the farm level.Genotype Environment Interaction reveals that G3,G4,and G2 were ideal lines with high potential yields,suitability,and adaptability on rainfed land.Participatory rice breeding in rainfed land integrates farmers’assessments and breeders’observations to realize the most preferred genotypes according to the challenges for sustainable agriculture.
基金supported by State Key Laboratory of Tree Genetics and Breeding(Northeast Forestry University)(K2013204)co-financed with NSFC project(31470673)Guangdong Science and Technology Planning Project(2016B070701008)
文摘To improve multi-environmental trial(MET)analysis,a compound method—which combines factor analytic(FA)model with additive main effect and multiplicative interaction(AMMI)and genotype main effect plus genotype-by-environment interaction(GGE)biplot—was conducted in this study.The diameter at breast height of 36 open-pollinated(OP)families of Pinus taeda at six sites in South China was used as a raw dataset.The best linear unbiased prediction(BLUP)data of all individual trees in each site was obtained by fitting the spatial effects with the FA method from raw data.The raw data and BLUP data were analyzed and compared by using the AMMI and GGE biplot.BLUP results showed that the six sites were heterogeneous and spatial variation could be effectively fitted by spatial analysis with the FA method.AMMI analysis identified that two datasets had highly significant effects on the site,family,and their interactions,while BLUP data had a smaller residual error,but higher variation explaining ability and more credible stability than raw data.GGE biplot results revealed that raw data and BLUP data had different results in mega-environment delineation,test-environment evaluation,and genotype evaluation.In addition,BLUP data results were more reasonable due to the stronger analytical ability of the first two principal components.Our study suggests that the compound method combing the FA method with the AMMI and GGE biplot could improve the analysis result of MET data in Pinus teada as it was more reliable than direct AMMI and GGE biplot analysis on raw data.
基金supported by the Bill and Melinda Gates Foundationthe Howard G.Buffett Foundation+4 种基金the United States Agency for International Development(USAID)through the Water Efficient Maize for Africa(WEMA)projectthe Stress Tolerant Maize for Africa(STMA)projectthe CGIAR Research Program MAIZEThe CGIAR Research Program MAIZE receives W1&W2 support from the Governments of Australia,Belgium,Canada,China,France,India,Japan,the Republic of Korea,Mexico,the Netherlands,New Zealand,Norway,Sweden,Switzerland,United Kingdom,the United States,and the World BankBrazilian Coordination for the Improvement of Higher Education Personnel(CAPES)for a scholarship supporting Wender Rezende
文摘Identification and deployment of high-yielding and stress-tolerant maize hybrids adapted to stress-prone agro-ecologies is important for improving the food security and livelihoods of smallholder farmers in eastern Africa.The objectives of this study were to(i)assess the performance of maize hybrids under well-watered and drought stress conditions;(ii)evaluate grain yield stability of 65 intermediate-maturing and 55 early-maturing hybrids in 24 well-watered locations and seven drought stress locations;and(iii)identify representative and/or discriminative testing locations for increasing genetic gains for the target traits.There were significant differences for grain yield among early-and intermediatematuring hybrids tested under well-watered and drought stress environments.Among the early-maturing hybrids,the top 10 hybrids produced 46.8%–73.9%and 31.2%–42.1%higher mean grain yields than the best commercial check under drought and well-watered conditions,respectively.Among the intermediate-maturing hybrids,the top 10 hybrids produced 25.2%–47.7%and 8.5%–13.5%higher grain yield than commercial checks under drought stress and well-watered conditions,respectively,suggesting improvement in the levels of drought tolerance in both early-and intermediate-maturing hybrids.GGE biplot analysis and a bi-segmented regression linear method identified specific early-maturing and intermediate-maturing hybrids that performed well under both well-watered and drought stress conditions.These hybrids could be recommended for commercial production in eastern Africa.Kakamega in Kenya was found to be the most representative and highly discriminating site among well-watered testing locations,while Kabuku in Tanzania was the least representative of test locations.For testing under drought stress conditions,Kiboko in Kenya was identified as the most representative location.This information could be useful for allocating resources and streamlining CIMMYT maize hybrid testing in eastern Africa.
基金supported by the National Basic Research Program of China (No. 2006CB101708)National Science and Technology Supporting Item of China (No. 2006BAD10A00).
文摘Crop seeds are important sources of protein, oil, and carbohydrates for food, animal feeds, and industrial products. Recently, much attention has been paid to quality and functional properties of crop seeds. However, seed traits possess some distinct genetic characteristics in comparison with plant traits, which increase the difficulty of genetically improving these traits. In this study, diallel analysis for seed models with genotype by environment interaction （GE） effect was applied to estimate the variance-covariance components of seed traits. Mixed linear model approaches were used to estimate the genetic covariances between pair-wise seed and plant traits. The breeding values （BV） were divided into two categories for the seed models. The first category of BV was defined as the combination of direct additive, cytoplasmic, and maternal additive effects, which should be utilized for selecting stable cultivars over multi-environments. The three genetic effects, together with their GE interaction, were included in the second category of BV for selecting special lines to be grown in specific ecosystems. Accordingly, two types of selection indices for seed traits, i.e., general selection index and interaction selection index, were developed and constructed on the first and the second category BV, respectively. These proposed selection indices can be applied to solve the difficult task of simultaneously improving multiple seed traits in various environments. Data of crop seeds with regard to four seed traits and four yield traits based on the modified diallel crosses in Upland cotton （Gossypium hirsutum L.） were used as an example for demonstrating the proposed methodology.
文摘Background Globally,the cultivation of cotton is constrained by its tendency for extended periods of growth.Early maturity plays a potential role in rainfed-based multiple cropping system especially in the current era of climate change.In the current study,a set of 20 diverse Gossypium hirsutum genotypes were evaluated in two crop seasons with three planting densities and assessed for 11 morphological traits related to early maturity.The study aimed to identify genotype(s)that mature rapidly and accomplish well under diverse environmental conditions based on the two robust multivariate techniques called multi-trait stability index(MTSI)and multi-trait genotype-ideotype distance index(MGIDI).Results MTSI analysis revealed that out of the 20 genotypes,three genotypes,viz.,NNDC-30,A-2,and S-32 accomplished well in terms of early maturity traits in two seasons.Furthermore,three genotypes were selected using MGIDI method for each planting densities with a selection intensity of 15%.The strengths and weaknesses of the genotypes selected based on MGIDI method highlighted that the breeders could focus on developing early-maturing genotypes with specific traits such as days to first flower and boll opening.The selected genotypes exhibited positive genetic gains for traits related to earliness and a successful harvest during the first and second pickings.However,there were negative gains for traits related to flowering and boll opening.Conclusion The study identified three genotypes exhibiting early maturity and accomplished well under different planting densities.The multivariate methods(MTSI and MGIDI)serve as novel approaches for selecting desired genotypes in plant breeding programs,especially across various growing environments.These methods offer exclusive benefits and can easily construe and minimize multicollinearity issues.
文摘Background:Genotype×environment interaction(GEI)slows genetic gains and complicates selection decisions in plant breeding programs.Forage breeding program seed sales often encompass large geographic regions to which the cultivars may not be adapted.An understanding of the extent of GEI in perennial,cool-season forage grasses will facilitate improved selection decisions and end-use in areas with harsh winters.Methods:We evaluated the dry matter yield of nine meadow brome(Bromus biebersteinii Roemer&J.A.Schultes),nine orchardgrass(Dactylis glomerata L.),seven tall fescue(Lolium arundinaceum(Schreb.)Darbysh.),and 10 timothy(Phleum pratense L.)cultivars or breeding populations at seven high latitude and/or elevation locations in Canada and the United States from 2019 to 2021.Results:For each of the species,we found significant differences among the genotypes for dry matter yield across environments and found significant levels of GEI.Using site regression analysis and GGE biplot visualizations,we then characterized the extent of the interactions in each species.Except for tall fescue,there was little evidence for the broad adaptation of genotypes across locations.Conclusions:This research adds further evidence to the limitations of perennial,forage breeding programs to develop widely adapted cultivars and the need to maintain regional breeding efforts.
文摘The present study focused on evaluating the agronomic performance, stability, and anthracnose resistance of common bean lines derived through Marker-Assisted Backcrossing in Uganda. Eight marker-assisted selection (MAS) backcross-derived bush bean lines with red seed types, alongside two checks, were evaluated in a randomized complete block design replicated two times in five locations for three consecutive crop-growing seasons in 2021 and 2022. The study aimed to identify lines with both high stable yields and enhanced resistance to anthracnose disease for potential release and utilization in future bean varietal development in Uganda. Agronomic traits, including days to 50% flowering, days to 90% physiological maturity, seed yield, seed yield components, and anthracnose disease reaction under natural infestation were assessed. The response to anthracnose disease was further assessed using six isolates of Colletotrichum lindemuthianum representing six different races. Results indicated that the agronomic performances of the MAS backcross-derived bush bean lines were statistically comparable to the recurrent parent NABE14. Specifically, six lines exhibited statistically equal to or higher performance than NABE14 in terms of seed yield, total number of seeds and number of pods per plant. The combined analysis of variance for seed yield showed significant (p Co-4<sup>2</sup> and Co-5 anthracnose resistance genes in the derived line. In conclusion, UGKT-B157-4, identified as the best-performing and stable genotype, demonstrates promise for release and use in future bean varietal development in Uganda, offering a combination of high yields and enhanced anthracnose disease resistance. The study provides valuable insights into the potential of Marker-Assisted Backcrossing in improving common bean varieties in the region.
基金the NationalNatural Science Foundation of China(300600433 and 39930110).
文摘Forty-seven spring wheat Triticumaestivum cultivars and advanced lines from spring-sown spring wheat regions, at twelve locations in 1998 and 1999, were used to investigate pasting properties of Chinese spring wheats. Starch pasting properties were closely associated with noodle quality. Significant differences were observed for all pasting characteristics. Samples collected from Harbin, Shenyang, Beijing, Ba-meng, Yongning, and Urumqi had better pasting quality than those from other locations. Genotype, environment, and genotype by environment interaction had large effects on all pasting characteristics. Significant correlations among pasting characteristics were observed and peak viscosity was considered the most important pasting characteristics.
基金supported by the Program of Introducing Talents of Discipline to University in China (Grant No.B08025)
文摘Genetic analysis of rolled leaf is important to rice ideotype breeding. To detect loci controlling rolled leaf of japonica restorer lines, SSR marker genotypes and phenotypes of flag leaf rolling index （LRI） were investigated in Xiushui 79 （P1, a japonica rice variety）, C Bao （P2, a japonica restorer line） and 254 recombinant inbred lines derived from the cross between P1 and P2 , and in two environments. A genetic map of this cross was constructed, QTLs for LRI were detected and their interactions with environments were analyzed. Among 818 pairs of SSR primers, 90 primers showed polymorphism between P1 and P2, and 12 markers showed highly significant correlation with LRI in both environments based on single marker regression analysis. The genetic map containing 74 information loci has a total distance of 744.6 cM, with an average of 10.1 cM between two adjacent loci. Three QTLs （qRL-1, qRL-7 and qRL-8-1） were detected with two softwares： WinQTLCart 2.5 and QTLNetwork2.0. qRL-8-1 was a new locus, accounting for 15.5% and 12.8% of phenotypic variations in the two environments, respectively. The phenotypic variation explained by additive effect was 6.6%. No interaction was found between qRL-8-1 genotype and environments.
基金supported by the National Key Research and Development Program of China(2021YFD2201200)the Fundamental Research Funds for the Central Universities(2572020DR01).
文摘Plant phenotypes are infl uenced by genetic and environmental factors.In this study,the growth traits of 43 one-year-old poplar clones grown at diff erent sites in northeast China(Dongling State-owned Forest Protection Center,DL;Baicheng State-owned forest farm,BC;and Cuohai Forest farm,CH)were evaluated and analyzed across clones and sites.Results show signifi cant diff erences in height and base diameter among sites and clones.Phenotypic and genetic variation coeffi cients ranged from 49.59%(BC)to 58.39%(DL)and from 49.33%(BC)to 58.06%(DL),respectively.Additive main eff ects and multiplicative interaction(AMMI)analysis showed that the eff ects of genotype,environment,and genotype×environment interaction were signifi cantly diff erent.Genetic variation was the main source of variation,accounting for 48.6%.AMMI biplot showed that clone 30 had high and stable yields at the three sites.From an evaluation of multiple traits and GGE biplot that clone 2,clone 30 and clone 25 had higher yield than the other clones at DL,CH and BC,respectively.These clones will provide material for forest regeneration in northeast China.
文摘The effects of genetic and environmental factors on Pinus koraiensis growth were studied based on a35 year-old progeny trial composed of open-pollinated offspring of twenty-one plus trees.Height,DBH and volume of the offspring was analyzed using restricted maximum likelihood/best linear unbiased prediction in mixed model analysis.Significant site and family effects on the three traits were observed.The distinct growth of offspring by site with disparate climates corroborated the importance of planting species in suitable conditions.Growth differences by family was significant,emphasizing the importance of identifying families with either superior or inferior performance.The parental ranking was assigned in the sites,inferring the breeding value of each plus tree.The estimates of individual heritability(h_(i)^(2))of height,DBH and volume growth were 0.169-0.645,0.108-0.331 and 0.129-0.343 respectively,with higher h_(i)^(2) of the height than DBH on each site.Coefficient of variance of genetic effect was higher with DBH in some cases,indicating the scope for selection is larger for this trait despite the lower heritability compared to height.For the variation between families in terms of the performance stability across sites,consideration of the genotype by environment interaction is required in selecting materials to be used in reforestation with Korean pine.A few families with either superior or inferior performance retained their parental ranking for at least a decade.Other families with increased growth on a particular site were identified,indicating their high breeding value and low stability.Differences in the genetic performance of the families by site requires delineation of the breeding region of the species.
文摘Cassava productivity is hampered by pests and diseases including cassava<span style="font-family:;" "=""><span style="font-family:Verdana;"> mosaic disease (CMD) and cassava brown streak disease (CBSD).</span><b> </b><span style="font-family:Verdana;">The main ob</span><span style="font-family:Verdana;">jective of this study was to identify stable superior genotypes that combine</span><span style="font-family:Verdana;"> dis</span><span style="font-family:Verdana;">ease resistance and high yield. Sixteen cassava genotypes were planted in a</span> <span style="font-family:Verdana;">randomized complete block design with three replications for six planting </span><span style="font-family:Verdana;">seasons (years) at five sites in Tanzania. The genotypes were assessed using the additive main effect and multiplicative interaction (AMMI) analysis, and highly significant (</span></span><span style="font-family:Verdana;">P </span><span style="font-family:Verdana;">< 0.001) effects of genotype, environment, and genotype-</span><span style="font-family:;" "=""><span style="font-family:Verdana;">by-environment (</span><i><span style="font-family:Verdana;">G</span><sup><span style="font-family:Verdana;">*</span></sup><span style="font-family:Verdana;">E</span></i><span style="font-family:Verdana;">) interactions were observed for all traits studied. Per</span><span style="font-family:Verdana;">cent sum of squares (SS) due to environment (12.66% - 85.23%) was the</span><span style="font-family:Verdana;"> highest followed by </span><i><span style="font-family:Verdana;">G</span><sup><span style="font-family:Verdana;">*</span></sup><span style="font-family:Verdana;">E</span></i><span style="font-family:Verdana;"> (14.12% - 39.56%) for CMD foliar symptoms, root weight and dry matter. On the other hand, % SS due to genotype (52.14% - 69.14%) </span><span><span style="font-family:Verdana;">was highest followed by </span><i><span style="font-family:Verdana;">G</span><sup><span style="font-family:Verdana;">*</span></sup><span style="font-family:Verdana;">E</span></i><span style="font-family:Verdana;"> (26.14% - 35.91%) for CBSD foliar and root</span></span><span style="font-family:Verdana;"> symptoms indicating that the environment and </span><i><span style="font-family:Verdana;">G</span><sup><span style="font-family:Verdana;">*</span></sup><span style="font-family:Verdana;">E</span></i><span style="font-family:Verdana;"> greatly influenced trait expression. The most stable genotypes which combined disease resistance and high yield were NDL 2003/31 and NDL 2003/111. The findings of this study will give impetus for the release of new cassava varieties that are not only high yielding but are also dually resistant to both CMD and CBSD in different locations and sites.</span></span>
基金To Fundacao de Amparoà Pesquisa do Estado de Minas Gerais,Conselho Nacional de Desenvolvimento Cientifico e Tecnológico e Coordenacao de Aperfeicoamento de Pessoal de Nível Superior,for supporting this research.
文摘Transgene insert location in the genome through different methods is random. Thus, alterations in the expression of desired trait may occur, as well as alterations in the expression of other characteristics of receptor plant. The purpose of this study was to compare Bt transgenic maize hybrids and the respective conventional isogenic hybrid in relation to adaptability and phenotypic stability. Field trails were set up in four locations of Minas Gerais, Brazil (Campo do Meio, Lavras, Madre de Deus and Paragua?u). A randomized complete block design was used, with three replications, and the treatment structure was a factorial 6 × 2, with six hybrids in the transgenic and conventional versions. Plant and ear height and grain yield were evaluated. To estimate stability, the Anicchiarico, Wricke and AMMI methodologies were used. Grain yield and ear height of the transgenic hybrids and their respective conventional isogenic hybrid did not differ. There are differences in the phenotypic stability between transgenic hybrids with Bt technology and their counterpart conventional isogenic hybrid.
基金supported by the Agriculture and Food Research Initiative competitive grant(2021-67013-33833)the USDA National Institute of Food and Agriculture,the Advanced Research Projects Agency-Energy program(DEAR0000826)+1 种基金the Department of Energy,the National Science Foundation(IOS-1546657)the Iowa State University Ray-mond F.Baker Center for Plant Breeding,and the Iowa State University Plant Sciences Institute.
文摘Identifying mechanisms and pathways involved in gene–environment interplay and phenotypic plasticity is a long-standing challenge.It is highly desirable to establish an integrated framework with an environmental dimension for complex trait dissection and prediction.A critical step is to identify an environmental index that is both biologically relevant and estimable for new environments.With extensive field-observed complex traits,environmental profiles,and genome-wide single nucleotide polymorphisms for three major crops(maize,wheat,and oat),we demonstrated that identifying such an environmental index(i.e.,a combination of environmental parameter and growth window)enables genome-wide association studies and genomic selection of complex traits to be conducted with an explicit environmental dimension.Interestingly,genes identified for two reaction-norm parameters(i.e.,intercept and slope)derived from flowering time values along the environmental index were less colocalized for a diverse maize panel than for wheat and oat breeding panels,agreeing with the different diversity levels and genetic constitutions of the panels.In addition,we showcased the usefulness of this framework for systematically forecasting the performance of diverse germplasm panels in new environments.This general framework and the companion CERIS-JGRA analytical package should facilitate biologically informed dissection of complex traits,enhanced performance prediction in breeding for future climates,and coordinated efforts to enrich our understanding of mechanisms underlying phenotypic variation.
