RESUMO
The performance differences in cassava genotypes arising from genotype vs. environment interactions (G × E) often lead to responses that are significantly lower than expected for selection. The objective of this study was to evaluate different stability methods, both parametric and non-parametric, such as additive main-effects and multiplicative interaction (AMMI), main effect of genotypes plus G × E (GGE), and weighted average of absolute scores (WAASB), in order to quantify the G × E in multi-environmental trials. A total of 12 genotypes were assessed across 12 environments using a completely randomized block design, with three replicates for traits such as fresh root yield (FRY) and dry matter content in the roots (DMC). The data were subjected to analysis of variance and the Scott Knott test (p < 0.05). The sum of squares (SQ) of genotypes, environment, and G × E effects were equally distributed for FRY, whereas for DMC, these effects accounted for 64.1%, 21.9%, and 13.8% of the SQ, respectively, indicating a lower environmental effect on this characteristic. Using the AMMI, GGE, and WAASB methods, genotypes with high agronomic performance and stability for FRY (BR11-34-41 and BR11-34-69) (> 32 t ha-1) and DMC (BRS Novo Horizonte, BR12-107-002, and BR11-24-156) (> 37%) were identified. The broad-sense heritability ( h 2 ) for FRY and DMC was estimated to be 0.45 and 0.75, respectively. Approximately 72% of the methods identified BRS Novo Horizonte as the genotype with the highest stability and performance for DMC, while 47% identified genotypes BR11-34-41 and BR11-34-69 for FRY and intermediate DMC. Genotype BR11-24-156 exhibited high static stability according to 50% of the methods. Significant correlations were observed between stability and agronomic performance across the different methods, enabling the formation of groups based on stability concepts. Additionally, it was found that two mega-environments existed for FRY, whereas DMC displayed a single mega-environment with similar patterns, indicating an absence of G × E. We identified superior genotypes that could be promoted to national performance trials to develop stable cultivars with better yield attributes in cassava. Supplementary Information: The online version contains supplementary material available at 10.1007/s10681-024-03384-5.
RESUMO
Genotype-environment interaction (GEI) presents challenges when aiming to select optimal cassava genotypes, often due to biased genetic estimates. Various strategies have been proposed to address the need for simultaneous improvements in multiple traits, while accounting for performance and yield stability. Among these methods are mean performance and stability (MPS) and the multi-trait mean performance and stability index (MTMPS), both utilizing linear mixed models. This study's objective was to assess genetic variation and GEI effects on fresh root yield (FRY), along with three primary and three secondary traits. A comprehensive evaluation of 22 genotypes was conducted using a randomized complete block design with three replicates across 47 distinct environments (year x location) in Brazil. The broad-sense heritability (H2) averaged 0.37 for primary traits and 0.44 for secondary traits, with plot-based heritability (hmÉ¡2) consistently exceeding 0.90 for all traits. The high extent of GEI variance (σÉ¡xe2) demonstrates the GEI effect on the expression of these traits. The dominant analytic factor (FA3) accounted for over 85% of the total variance, and the communality (ɧ) surpassed 87% for all traits. These values collectively suggest a substantial capacity for genetic variance explanation. In Cluster 1, composed of remarkably productive and stable genotypes for primary traits, genotypes BRS Novo Horizonte and BR11-34-69 emerged as prime candidates for FRY enhancement, while BRS Novo Horizonte and BR12-107-002 were indicated for optimizing dry matter content. Moreover, MTMPS, employing a selection intensity of 30%, identified seven genotypes distinguished by heightened stability. This selection encompassed innovative genotypes chosen based on regression variance index (Sdi2, R2, and RMSE) considerations for multiple traits. In essence, incorporating methodologies that account for stability and productive performance can significantly bolster the credibility of recommendations for novel cassava cultivars.
RESUMO
Abstract The objective of this study was to evaluate the biomass and essential oil production of nine populations of poejo (Cunila galioides) cultivated in five agroecological regions of the state of Rio Grande do Sul, under different edaphoclimatic conditions. The experiments were performed in field conditions in Erechim, Caxias do Sul, Pelotas, São Francisco de Paula, and Santa Vitoria do Palmar. The experimental design was completely randomized, with nine populations, eight plants per plot and four repetitions. The following were evaluated: biomass production and essential oil chemical composition and yield. The data underwent ANOVA, followed by Tukey's multiple range test. The adaptability and stability of the populations in the different environments were also evaluated by regression analysis. The results showed great differences between the populations and cultivation sites, with genotype vs. environment interaction. Most populations presented the best biomass production results at Erechim. Pelotas and Santa Vitória do Palmar were the worst locations for poejo production, mainly due to a water deficit occurred during the experiment. The Santa Lucia population presented broad stability and the greatest adaptability to the environments for biomass and essential oil production, but its average production was not satisfactory. The André da Rocha population presented the highest average production of essential oil, and was favored in favorable environments. Regarding essential oil chemical composition, the populations kept stable contents of the major compounds at all locations, with a few variations. In some populations, a higher concentration of sesquiterpenes was observed, which can be attributed to environmental stress.
Assuntos
Óleos de Plantas/química , Óleos Voláteis/química , Biomassa , Lamiaceae/genética , Sesquiterpenos , Solo/química , Clima Tropical , Análise de Regressão , Análise de Variância , GenótipoRESUMO
The utilization of diallel crosses for identification of superior combinations is a common practice in maize (Zea mays L.) breeding programs. This methodology allows the estimation of the combining ability of genotypes being evaluated. In this work, five inbred lines were evaluated as to their general (GCA) and specific (SCA) combining abilities, by using a complete diallel scheme. The single-crosses produced between these inbred lines were evaluated in seven environments, along with two checks, by using a randomized complete block design. Traits analized were: grain yield, plant height, ear height, ear placement, and prolificacy. A diallel analysis was carried out, following an adaptation of Griffing's method IV, in addition to hybrid stability and adaptability analyses. Significant differences were detected for entries and environments for all traits. The interaction genotype vs. environment was significant for all traits. GCA's were significant for all traits, while SCA's were non-significant only for ear placement. For grain yield, both additive (GCA) and non-additive (SCA) effects were important, while for the remaining traits additive effects were more important. The high yielding single-cross was obtained from the cross of lines L-08-05F and L-38-05D. Those inbred lines showed higher GCA's and their cross also had high SCA; also, it is responsive to environment improvements and reasonably stable. The second in rank high yielding single-cross, L-46-10D x L-08-05F, showed wide adaptability and stability.
No melhoramento de milho (Zea mays L.), a utilização de cruzamentos dialélicos visando identificação de combinações superiores é uma prática comum. Esta metodologia visa estimar a capacidade de combinação dos materiais avaliados. Neste trabalho, cinco linhagens endogâmicas foram avaliadas quanto às capacidades gerais (CGC) e específica (CEC) de combinação, utilizando o esquema de dialelo completo. Os híbridos simples produzidos entre estas linhagens foram avaliados em sete ambientes, juntamente com duas testemunhas, tendo-se utilizado o delineamento de blocos casualizados. Avaliaram-se os caracteres: produção de grãos, altura da planta, altura da espiga, posição relativa da espiga e prolificidade. Realizou-se a análise dialélica, seguindo uma adaptação do método IV de Griffing, além das análises de estabilidade e adaptabilidade dos híbridos. Detectaram-se diferenças significativas para tratamentos e ambientes para todos os caracteres. A interação genótipos por ambientes foi significativa para maioria dos caracteres. As CGCs foram significativas para todos os caracteres, enquanto que a CEC foi não significativa apenas para posição relativa da espiga. Para o caráter produção de grãos, tanto os efeitos aditivos (CGC) quanto não aditivos (CEC) foram importantes, enquanto que para os demais caracteres, houve predominância dos efeitos aditivos. O híbrido mais produtivo foi obtido entre as linhagens L-08-05F e L-38-05D. Suas linhagens apresentaram elevadas CGCs e seu híbrido, elevada CEC, além de ter sido responsivo à melhoria das condições ambientais e razoavelmente estável. O segundo híbrido mais produtivo, L-46-10D x L-08-05F, mostrou ampla adaptabilidade e estabilidade.
RESUMO
The utilization of diallel crosses for identification of superior combinations is a common practice in maize (Zea mays L.) breeding programs. This methodology allows the estimation of the combining ability of genotypes being evaluated. In this work, five inbred lines were evaluated as to their general (GCA) and specific (SCA) combining abilities, by using a complete diallel scheme. The single-crosses produced between these inbred lines were evaluated in seven environments, along with two checks, by using a randomized complete block design. Traits analized were: grain yield, plant height, ear height, ear placement, and prolificacy. A diallel analysis was carried out, following an adaptation of Griffing's method IV, in addition to hybrid stability and adaptability analyses. Significant differences were detected for entries and environments for all traits. The interaction genotype vs. environment was significant for all traits. GCA's were significant for all traits, while SCA's were non-significant only for ear placement. For grain yield, both additive (GCA) and non-additive (SCA) effects were important, while for the remaining traits additive effects were more important. The high yielding single-cross was obtained from the cross of lines L-08-05F and L-38-05D. Those inbred lines showed higher GCA's and their cross also had high SCA; also, it is responsive to environment improvements and reasonably stable. The second in rank high yielding single-cross, L-46-10D x L-08-05F, showed wide adaptability and stability.
No melhoramento de milho (Zea mays L.), a utilização de cruzamentos dialélicos visando identificação de combinações superiores é uma prática comum. Esta metodologia visa estimar a capacidade de combinação dos materiais avaliados. Neste trabalho, cinco linhagens endogâmicas foram avaliadas quanto às capacidades gerais (CGC) e específica (CEC) de combinação, utilizando o esquema de dialelo completo. Os híbridos simples produzidos entre estas linhagens foram avaliados em sete ambientes, juntamente com duas testemunhas, tendo-se utilizado o delineamento de blocos casualizados. Avaliaram-se os caracteres: produção de grãos, altura da planta, altura da espiga, posição relativa da espiga e prolificidade. Realizou-se a análise dialélica, seguindo uma adaptação do método IV de Griffing, além das análises de estabilidade e adaptabilidade dos híbridos. Detectaram-se diferenças significativas para tratamentos e ambientes para todos os caracteres. A interação genótipos por ambientes foi significativa para maioria dos caracteres. As CGCs foram significativas para todos os caracteres, enquanto que a CEC foi não significativa apenas para posição relativa da espiga. Para o caráter produção de grãos, tanto os efeitos aditivos (CGC) quanto não aditivos (CEC) foram importantes, enquanto que para os demais caracteres, houve predominância dos efeitos aditivos. O híbrido mais produtivo foi obtido entre as linhagens L-08-05F e L-38-05D. Suas linhagens apresentaram elevadas CGCs e seu híbrido, elevada CEC, além de ter sido responsivo à melhoria das condições ambientais e razoavelmente estável. O segundo híbrido mais produtivo, L-46-10D x L-08-05F, mostrou ampla adaptabilidade e estabilidade.
RESUMO
Corn is present in a great number of products and its area and production is growing in the world. In 1991/92 two evaluation trials were conducted in a complete randomised block design and three replications, with 36 hybrids of nine inbred lines in "Não Me Toque" and "Tapera", both in the state of Rio Grande do Sul, with the aim of evaluating the genetic diversity and combining ability of these hybrids for ear height, stalk-root, lodging, prolificacy and grain yield. The significant interaction for CGA and SCA with location showed that the genotypes had different performance in the two environments. The inbred lines in the best combinations were the same at the two locations, showing that the CGA was a good indicator of inbred lines performance at hybrid combinations, although the best hybrids were not the same at the two locations. The best inbred lines were ID01, IMD04, IMD06 and ID09.
O milho é um cereal que faz parte de um grande número de produtos e apresenta produção crescente em nível mundial. A maior parte das áreas produtivas no Brasil são ocupadas por híbridos obtidos a partir de linhagens endogâmicas. Nos anos de 1991/92, foram conduzidos dois experimentos em blocos ao acaso e três repetições, com 36 híbridos de nove linhagens endogâmicas de milho em Não Me Toque e Tapera, ambos locais no Rio Grande do Sul, com o objetivo de avaliar estes híbridos quanto à capacidade combinatória em dois ambientes, para os caracteres altura de inserção da espiga superior, porcentagem de tombamento, prolificidade e rendimento de grãos. A significância da interação C.G.C. e C.E.C. com ambiente, evidenciou as diferenças de comportamento dos genótipos nos dois locais. As linhagens presentes nas melhores combinações foram as mesmas nos dois ambientes, mostrando que a C.G.C. foi um bom indicador do desempenho das linhagens em combinações híbridas, embora os melhores híbridos não tenham sido os mesmos nos dois locais. As linhagens que se destacaram foram ID01, IMD04, IMD06 e ID09.
RESUMO
Corn is present in a great number of products and its area and production is growing in the world. In 1991/92 two evaluation trials were conducted in a complete randomised block design and three replications, with 36 hybrids of nine inbred lines in "Não Me Toque" and "Tapera", both in the state of Rio Grande do Sul, with the aim of evaluating the genetic diversity and combining ability of these hybrids for ear height, stalk-root, lodging, prolificacy and grain yield. The significant interaction for CGA and SCA with location showed that the genotypes had different performance in the two environments. The inbred lines in the best combinations were the same at the two locations, showing that the CGA was a good indicator of inbred lines performance at hybrid combinations, although the best hybrids were not the same at the two locations. The best inbred lines were ID01, IMD04, IMD06 and ID09.
O milho é um cereal que faz parte de um grande número de produtos e apresenta produção crescente em nível mundial. A maior parte das áreas produtivas no Brasil são ocupadas por híbridos obtidos a partir de linhagens endogâmicas. Nos anos de 1991/92, foram conduzidos dois experimentos em blocos ao acaso e três repetições, com 36 híbridos de nove linhagens endogâmicas de milho em Não Me Toque e Tapera, ambos locais no Rio Grande do Sul, com o objetivo de avaliar estes híbridos quanto à capacidade combinatória em dois ambientes, para os caracteres altura de inserção da espiga superior, porcentagem de tombamento, prolificidade e rendimento de grãos. A significância da interação C.G.C. e C.E.C. com ambiente, evidenciou as diferenças de comportamento dos genótipos nos dois locais. As linhagens presentes nas melhores combinações foram as mesmas nos dois ambientes, mostrando que a C.G.C. foi um bom indicador do desempenho das linhagens em combinações híbridas, embora os melhores híbridos não tenham sido os mesmos nos dois locais. As linhagens que se destacaram foram ID01, IMD04, IMD06 e ID09.