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Abstract 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.

The management of intraspecific diversity in many species is usually disconnected from eco‐evolutionary processes happening in natura. A classic example is embodied in the problem of introgression in hybridized fish populations, wherein management practices are generally unaware of any selective process at work, and therefore generally rely on numbers (adding or removing individuals) to reduce introgression. Such an example can be observed in the French Alps, where native Mediterranea (MED) brown trout have been highly introgressed through decades of stocking with domesticated Atlantic (ATL) brown trout. Recently however, new results shed light on a potential selective mechanism that may affect differentially the fitness of MED and ATL genes depending on the environment (GxE interaction). Using a demogenetic agent‐based model able to account for such GxE interaction, we simulate a management scenario implemented in 2005 by some biodiversity managers and scientists, who attempted to restore the Mediterranea gene pool using translocation of near pure MED individuals in Atlantic‐dominated areas. We show that the model is unable to recreate the observed introgression dynamics if the GxE interaction is not included. This finding implies that (i) eco‐evolutionary mechanisms can have large effects on introgression dynamics on very short time scales and (ii) management of intraspecific diversity should increasingly rely on these natural mechanisms, so as to improve management targets and facilitate adaptation to rapid environmental changes. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the yield, growth rate, plant height and crude protein, ash and neutral detergent fiber contents in six genotypes of Medicago sativa L. and on two high Andean plateaus of northern Peru. Materials and Methods: A complete randomized block design was used. The M. sativa varieties (SW10, W450, HORTUS 401, W350, SW8210 and STAMINO 5) were considered the treatments, distributed in three blocks, repeated in the two localities, with a total of 36 experimental units. The chemical composition, green forage and dry matter yield, growth rate and plant height in the six genotypes and their interaction, were evaluated. The analysis of the productive indicators was done through variance analysis. In addition, Pearson’s correlation tests were carried out to find relation between plant height and biomass yield. Results: The altitudinal plateau I achieved 10 241,8 kg/ha/cut of green forage and 61 450,6 kg/ha/year, 1 739,9 kg/ha/cut and 10 498 kg/ha/year of dry matter, with the best production. The variety W-450 had higher average green forage yield (56 963 kg/ha/year) and dry matter (10 483,9 kg/ha/year). Plant height varied from 22,4 to 35,5 cm and crude protein from 16,7 to 21,2 %. The ash records were from 9,3 to 12,0 % and neutral detergent fiber from 24,2 to 32,5 %. Conclusions: All the varieties showed high potential for forage production under the conditions of both altitudinal plateaus. Likewise, the environmental conditions were determinant in the performance of the different genotypes.

In Nariño, the climbing pea varieties, due to their high production capacity, are unable to stand upright despite the use of trellising systems, resulting in lodging and losses in yield and product quality. A viable option to mitigate the problem is the use of climbing genotypes with the afila gene that replaces leaves with tendrils, favoring the grip of the plants on the strings that serve as tutors. In search of a solution to this problem, the adaptability and phenotypic stability for green pod yield of 20 climbing pea lines with the afila gene and the normal-leaf controls Obonuco Andina and Sindamanoy were evaluated in five municipalities in the southern part of the department of Nariño. A randomized complete block design with four replications was used at each location. The data obtained were analyzed using the Eberhart and Russell and AMMI models. In the Eberhart and Russell model, the most favorable environments were Puerres and Gualmatán and the most unfavorable environment was Potosí. Lines GR15, GR10 and the Sindamanoy variety were selected as high yielding, adaptable and predictable. The analysis of variance for the AMMI model indicated a high environmental effect, resulting from contrasting environments and low diversity between the lines with the afila gene evaluated. The selection index (GSIi) obtained from the stability value (ASV) and the classification by yield, allowed the identification and selection in order of merit of the genotypes Obonuco Andina, GR15, GR14, GR28, GR10, GR2, GR23, Sindamanoy and GR3 as those with the highest stability and yield. The coincidence in selection between the Eberhart and Russell and AMMI models was 33,3%. [ABSTRACT FROM AUTHOR]

The current work was studied the interaction of genotype environment for alfalfa seed yield. The split block design in three replications used for this study. Five sowing dates of 10th October (D1), 10th November (D2), 10th December (D3), 20th March (D4) and 20th April (D5) were used. Seed yield was taken in the second year in the beginning of March, April and May for studied sowing dates. The genotype plus genotype by environment interaction (GGE) biplot analysis was done. The obtained results showed that the environments exhibited high contribution in the total sum of squares for seed yield/plant (SYP) and seed yield/m² (SYW) in values of 60.69 and 60.80%, respectively, which accounted ten times of genotypes contribution. PC1 and PC2 were significant factors as revealed from GGE-biplot analysis and explaining 40.23 and 21.36% for seed yield/ plant and 37.04 and 17.83% for seed yield/m² in total sum of squares, respectively. According to the GGE-biplot analysis, the genotype G9 was the highest seed yield and stable genotype across environments and the environment E4 (sowing at 20th March) was yielded the highest seed yield/ plot which recorded 66.06 g. [ABSTRACT FROM AUTHOR]

Copyright of Revista Ciencia y Tecnología Agropecuaria is the property of Agrosavia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: To evaluate the yield, growth rate, plant height and crude protein, ash and neutral detergent fiber contents in six genotypes of Medicago sativa L. and on two high Andean plateaus of northern Peru. Materials and Methods: A complete randomized block design was used. The M. sativa varieties (SW10, W450, HORTUS 401, W350, SW8210 and STAMINO 5) were considered the treatments, distributed in three blocks, repeated in the two localities, with a total of 36 experimental units. The chemical composition, green forage and dry matter yield, growth rate and plant height in the six genotypes and their interaction, were evaluated. The analysis of the productive indicators was done through variance analysis. In addition, Pearson's correlation tests were carried out to find relation between plant height and biomass yield. Results: The altitudinal plateau I achieved 10 241,8 kg/ha/cut of green forage and 61 450,6 kg/ha/year, 1 739,9 kg/ha/ cut and 10 498 kg/ha/year of dry matter, with the best production. The variety W-450 had higher average green forage yield (56 963 kg/ha/year) and dry matter (10 483,9 kg/ha/year). Plant height varied from 22,4 to 35,5 cm and crude protein from 16,7 to 21,2 %. The ash records were from 9,3 to 12,0 % and neutral detergent fiber from 24,2 to 32,5 %. Conclusions: All the varieties showed high potential for forage production under the conditions of both altitudinal plateaus. Likewise, the environmental conditions were determinant in the performance of the different genotypes. [ABSTRACT FROM AUTHOR]

Cane yield and juice quality traits are essential and important in release of sugarcane variety for commercial cultivation. Twenty elite sugarcane clones along with two popular standards (Co 86032 and PI 1110) were evaluated at Sakthi sugars, Sivaganga, in two plant crops and one ratoon crop for 2 years to identify a variety suitable for this location. Cane yield (t/ha), commercial cane sugar (CCS) yield (t/ha), CCS % at harvest, juice sucrose %, juice brix %, juice purity %, single cane weight (kg), stalk height (cm) and stalk diameter (cm) at harvest were considered for the study. Within environment analysis of variance (ANOVA) indicated significant differences among genotypes for almost all the traits in all three environments (two plant and one ratoon crops). Combined ANOVA results displayed non-significant genotype environment interaction for all the traits except height and diameter. Cane yield and sugar yield were significant higher in II (second) plant crop compared to I (first) plant and ratoon crops, whereas no significance was observed for other traits. Heritability estimates were higher for juice quality traits as compared to cane traits. Single cane weight recorded highest estimates for repeatability and heritability of means over harvests. Best linear unbiased predictions were estimated for all the traits through restricted maximum likelihood method for individual crops and pooled data. The clone Co 09004 recorded high estimates for quality traits, and clone Co 11015 was found to be superior for both yield and quality traits. [ABSTRACT FROM AUTHOR]

Abstract Background Cold temperatures and their alleviation affect many plant traits including the abundance of protein coding gene transcripts. Transcript level changes that occur in response to cold temperatures and their alleviation are shared or vary across genotypes. In this study we identify individual transcripts and groups of functionally related transcripts that consistently respond to cold and its alleviation. Genes that respond differently to temperature changes across genotypes may have limited functional importance. We investigate if these genes share functions, and if their genotype-specific gene expression levels change in magnitude or rank across temperatures. Results We estimate transcript abundances from over 22,000 genes in two unrelated Zea mays inbred lines during and after cold temperature exposure. Genotype and temperature contribute to many genes’ abundances. Past cold exposure affects many fewer genes. Genes up-regulated in cold encode many cytokinin glucoside biosynthesis enzymes, transcription factors, signalling molecules, and proteins involved in diverse environmental responses. After cold exposure, protease inhibitors and cuticular wax genes are newly up-regulated, and environmentally responsive genes continue to be up-regulated. Genes down-regulated in response to cold include many photosynthesis, translation, and DNA replication associated genes. After cold exposure, DNA replication and translation genes are still preferentially downregulated. Lignin and suberin biosynthesis are newly down-regulated. DNA replication, reactive oxygen species response, and anthocyanin biosynthesis genes have strong, genotype-specific temperature responses. The ranks of genotypes’ transcript abundances often change across temperatures. Conclusions We report a large, core transcriptome response to cold and the alleviation of cold. In cold, many of the core suite of genes are up or downregulated to control plant growth and photosynthesis and limit cellular damage. In recovery, core responses are in part to prepare for future stress. Functionally related genes are consistently and greatly up-regulated in a single genotype in response to cold or its alleviation, suggesting positive selection has driven genotype-specific temperature responses in maize.

Copyright of Revista Ciencia y Tecnología Agropecuaria is the property of Agrosavia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objectives were to analyze the presence of genetic variance in the residual variance of behavior notes in fighting bulls. From a livestock ranch, the conditional residuals were analyzed (RCON; ê = y - [y|a] = y - Xß - Za) and marginal (RMAR; = y - [y] = y - Xß), from the notes of horse tienta (n, 2369), foot tienta (n, 1432), horse bullfight (n, 792) and foot bullfighter (n, 820); in two databases: BD1, logarithmic transformation; BD2, logarithmic transformation eliminating extreme data (x ±2s). With the MTDFREML software, a multivariate analysis (four notes) was performed within the residual type and for each database; heritability (h) and genetic correlations (rg) were calculated through variables. The h2 ranged between 0.14 and 0.96, with an average value of 0.58; h2 of RMAR in BD2 presented above estimates (> 0.78). These results show genetic variability in the residual variance and present the possibility of response to selection (environmental channeling) to reduce environmental variance. The selection for residual variance can improve the response to the concepts of resilience, plasticity, robustness and rusticity. The rg were positive, in the range of 0.01 to 0.99 and an average value of 0.79; with these rg there may be a correlated response in the residuals of the four notes. [ABSTRACT FROM AUTHOR]

Copyright of Nativa is the property of Revista Nativa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Agraria Kaposváriensis is the property of Faculty of Agricultural & Environmental Sciences, University of Kaposvarr and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

El uso actual de estevia, a escala industrial, se ha incrementado a nivel mundial, argumento que conlleva a buscar zonas de mejor adaptación del cultivo, en muchas regiones del país. El objetivo de este trabajo fue analizar la estabilidad de los rendimientos y los contenidos de glucósidos de esteviol de Stevia rebaudiana Bert., en función de la oferta de luz de cinco regiones de Colombia. En cada sitio, se construyeron cinco parcelas experimentales del cultivar Morita II, en las localidades de Montería, Córdoba; Campamento, Antioquia; Palmira , Valle del Cauca; Fonseca, La Guajira y Valledupar, Cesar, bajo un diseño de bloques completos al azar, con dos tratamientos de radiación difusa y directa, con cinco repeticiones. Se cuantificaron los contenidos de esteviósido (Stv), rebaudiósido A (RebA), glucósidos principales (GP) en mg.kg-1 de hoja seca, por cromatografía líquida de alta eficacia; la relación RebA/Stv y el rendimiento de hoja seca, en kg.ha-1. Se realizó análisis de varianza y prueba de comparación de medias de Duncan (α=0,05). Los niveles de radiación no afectaron la síntesis de Stv y RebA, tampoco se presentó interacción entre los niveles de radiación de las localidades. Se registraron diferencias significativas en los contenidos de Stv, RebA y la relación RebA/Stv, entre las localidades. En Palmira, con 132,26mg.kg-1, se obtuvieron los mayores contenidos de RebA, mientras que la mayor relación RebA/Stv de 10:1mg.g-1, que define la calidad de la hoja, se observó en Montería.

Background: Cold temperatures and their alleviation affect many plant traits including the abundance of protein coding gene transcripts. Transcript level changes that occur in response to cold temperatures and their alleviation are shared or vary across genotypes. In this study we identify individual transcripts and groups of functionally related transcripts that consistently respond to cold and its alleviation. Genes that respond differently to temperature changes across genotypes may have limited functional importance. We investigate if these genes share functions, and if their genotype-specific gene expression levels change in magnitude or rank across temperatures. Results: We estimate transcript abundances from over 22,000 genes in two unrelated Zea mays inbred lines during and after cold temperature exposure. Genotype and temperature contribute to many genes' abundances. Past cold exposure affects many fewer genes. Genes up-regulated in cold encode many cytokinin glucoside biosynthesis enzymes, transcription factors, signalling molecules, and proteins involved in diverse environmental responses. After cold exposure, protease inhibitors and cuticular wax genes are newly up-regulated, and environmentally responsive genes continue to be up-regulated. Genes down-regulated in response to cold include many photosynthesis, translation, and DNA replication associated genes. After cold exposure, DNA replication and translation genes are still preferentially downregulated. Lignin and suberin biosynthesis are newly down-regulated. DNA replication, reactive oxygen species response, and anthocyanin biosynthesis genes have strong, genotype-specific temperature responses. The ranks of genotypes' transcript abundances often change across temperatures. Conclusions: We report a large, core transcriptome response to cold and the alleviation of cold. In cold, many of the core suite of genes are up or downregulated to control plant growth and photosynthesis and limit cellular damage. In recovery, core responses are in part to prepare for future stress. Functionally related genes are consistently and greatly up-regulated in a single genotype in response to cold or its alleviation, suggesting positive selection has driven genotype-specific temperature responses in maize. [ABSTRACT FROM AUTHOR]

In order to evaluate the bromatológica composition of silage from experimental and commercial hybrids of maize at different levels of phosphate fertilization, an experiment was conducted in the 2012/2013 harvest at the Federal University of Tocantins, located in Municipality of Gurupi - TO, using the experimental design in randomized blocks, with two repetitions, considering high phosphorus (p) The fertilization of 120 kg ha-1 of P2O5 and Low phosphorus (p) The fertilization of 20 kg ha-1 of P2O5. The characteristics evaluated were concentration of nitrogen, phosphorus, potassium, crude protein, digestible protein, fresh mass and dry mass. In nitrogen concentrations irrespective of the environment, the hybrid BM 2202 presented the highest average, in phosphorus concentrations in silage the high doses were always higher than the low dose due to the availability of the nutrient to the plant. The hybrid that obtained the highest potassium average was the commercial P 30F80. As for the raw protein and protein digestible the hybrid BM 2202 presented the largest medium, but not differentiated from the hybrids PS-015, PS-002, Impact and PS-001. The averages of fresh mass and dry mass did not differ statistically. For the low P environment, the hybrid PS-006, PS- 010, PS-014, PS-015, PS-023 and P 30F53Y are indicated. [ABSTRACT FROM AUTHOR]

In a hypothetic population of cotton, Gossypium hirsutum L., segregating for 26 independent alleles, individuals with all desired alleles are more abundant in early generations (F2 or F3), but a high proportion of allelic loci are homozygous in late generations (F4 or F5). This dichotomy needs to be considered to establish a successful breeding strategy. In this study, we examined the effectiveness of two pedigree procedures in cotton with their key difference in the self-generations used for single plant selection. The conventional procedure started single plant selection at F3 by hand-harvest of a 30-boll sample from individual plants, then in the follow-up generation, only those derived lines retained after culling for lint percent and High Volume Instrument (HVI) fibre quality entered the progeny row test. The alternative procedure used single-locule descent for pass-through of early generations; at F5, only two mature bolls were harvested from selected individual plants, and their derived lines were grown and culled in single-row plot nursery by visual assessment, and by lint percent and HVI fibre properties measured from a 30-boll sample. When each procedure was used to develop elite inbred lines in two populations derived from outstanding cotton lines, both procedures were effective at identifying elite lines from the populations. The alternative procedure captured more elites than the conventional one, based on the retention rate against the initial population size, particularly in one population, and required less resources in the process. Thus, the alternative procedure with delayed single plant selection is effective and efficient for cotton improvement. [ABSTRACT FROM AUTHOR]

Selecting high yielding genotypes with stable performance is the breeders’ priority but is constrained by genotype × environment (G×E) interaction. We investigated canola yield of 35 genotypes and its stability in multiple environment trials (MET) in south-western Australia and the possibility to breed broadly-adapted high yielding genotypes. The Finlay–Wilkinson (F–W) regression and factor analytic (FA) model were used to investigate the G×E interaction, yield and genotype stability and adaptability. The cross-over response in the F–W regression, substantial genetic variance heterogeneity, and the genetic correlations in the FA model demonstrated substantial G×E interaction for yield. Cluster analysis suggests low, medium and high rainfall mega-environments. F–W regression indicated that genotypes with high stability (e.g. low regression slope values) produced relatively low yield and vice versa, but also identified broadly adapted genotypes with high intercepts and steep regression slopes. The FA model provided a more detailed analysis of performance, dividing genotypes by positive, flat or negative responses to environment. In general, early flowering genotypes responded negatively to favourable environments and vice versa for late flowering genotypes. More importantly, a few early flowering hybrids with long flowering phases were consistently productive in both low and high yielding environments, showing broad adaptability. These productive hybrids were consistent with those identified earlier by high F–W intercept and slope values. Hybrids were higher yielding and more stable than open-pollinated canola, as was Roundup-Ready® canola compared to the three other herbicide tolerance groups (Clearfield®, Triazine tolerant, conventional). We conclude that yield stability and high yield are not mutually exclusive and that breeding for broadly adapted high yielding canola is possible. [ABSTRACT FROM AUTHOR]

O desempenho de linhagens promissoras de arroz, gerado pelo programa de melhoramento genético do Instituto Agronômico (IAC) foi avaliado em diferentes ambientes. Os ensaios foram instalados em blocos casualizados com quatro repetições e parcelas experimentais com área útil de 6 m² nos anos agrícolas de 2006/2007, 2007/2008, 2008/2009 e 2009/2010, nos municípios de Capão Bonito-SP e Mococa-SP. A variação total dos dados de produção de grãos foi analisada pela ANAVA e pela ANADEV, e foram estimadas as significâncias dos efeitos da interação genótipo x ambiente pelas duas metodologias. A adaptabilidade e estabilidade de 16 genótipos de arroz de terras altas em 8 ambientes foram avaliadas pelos métodos de Eberhart e Russell (1966) e Lin e Binns (1988) e pela metodologia dos modelos mistos (REML/BLUP). Pelo método da média harmônica da performance relativa dos valores genotípicos (MHPRVG) foram selecionadas as linhagens IAC 2009, IAC 1829 e IAC 2005 com produções superiores em 11; 10 e 6% respectivamente, em relação à média geral, o que foi coincidente com os resultados obtidos pelas outras metodologias.The performance of promising strains of rice, generated through the genetic improvement program of the Instituto Agronômico (IAC), was evaluated for different environments. The experiments were set up in a randomized-block design with four replications, using experimental plots of 6m², during the periods 2006/2007, 2007/2008, 2008/2009 and 2009/2010, in the municipalities of de Capão Bonito and Mococa, both in São Paulo. The total variation of the data for grain-production was analyzed using ANAVA and ANADEV, and the significance of the effects of the interaction between genotype and environment were estimated for the two methodologies. The adaptability and stability of 16 genotypes of upland rice in eight environments were evaluated using the methods of Eberhart and Russell (1966), Lin and Binns (1988), and mixed-model (REML / BLUP). Using the harmonic mean of the relative performance of genotypic values (MHPRVG), the strains, IAC 2009, IAC 1829 and IAC 2005 were selected, with yields superior to 11; 10 and 6% respectively when compared to the general average, which matched results obtained by other methods.

To better understand the mechanisms that allow some animals to sustain their productive effort in harsh environmental conditions, rabbit does from two selection lines (LP and V) were housed in normal (NC), nutritional (NF) or heat (HC) challenging environmental conditions from first to third partum. The LP line (n=85) was founded on reproductive longevity criteria by selecting does from commercial farms that had a minimum of 25 partum with more than 7.5 kits born alive per parity. Line V (n=79) was constituted from four specialised maternal lines into a composite synthetic line and then selected by litter size at weaning for 36 generations. Female rabbits in NC and NF environments were housed at normal room temperature (18°C to 24°C) and fed with control [11.6 MJ digestible energy (DE)/kg dry matter (DM)] or low-energy diets (9.1 MJ DE/kg DM). HC does were housed at high room temperatures (25°C to 35°C) and fed the control diet. Female rabbits in the HC and NF environments ingested 11.5% and 6% less DE than NC does, respectively (P

A seleção e recomendação de genótipos superiores são dificultadas devido à ocorrência da interação genótipo e ambiente. Nesse contexto, as análises biplot têm sido cada vez mais utilizadas na análise de dados agronômicos, com interações de natureza complexa. Entretanto, as particularidades existentes no gráfico biplot dificultam sua interpretação, podendo induzir o pesquisador a erros. Assim, este artigo de revisão discute a aplicabilidade e a interpretação gráfica dos modelos AMMI (Additive Main effects and Multiplicative Interaction) e GGE biplot (genotype main effects + genotype environment interaction) destas análises no gráfico biplot. Também, visa a desmistificar a necessidade de comparação entre ambas as metodologias. Discute-se quanto à escolha da metodologia mais adequada, levando em consideração a informação requerida e os objetivos do pesquisador.The genotype environment interaction (GE) influences on the selection and recommendation of cultivars. Biplot analysis has been increasingly used in data analysis of complex traits in agriculture. However, the peculiarities of biplot graphic could induce the researcher to errors on interpretation. Thus, this review argues the applicability and graphic interpretation of models AMMI (Additive Main Effects and Multiplicative Interaction) and GGE biplot (genotype main effects + genotype environment interaction). Moreover, also aims to explain that it is not adequate to compare both statistical methods. It is discussed the best methodology considering the information required and the research objectives.

An investigation was conducted to determine the grain yield performance of seventy two single cross maize hybrids, theirnine parents and one commercial check across three seasons (Summer, Kharif and Rabi) of the year 2006 at the Departmentof Millets, Tamil Nadu Agricultural University, Coimbatore. The design lay out was a randomized blocks design with threereplications. The additive main effects and multiplicative interactions (AMMI) analysis indicated that the grain yieldperformance of maize genotypes were mainly due to genotypes and environmental interaction. The first two principalcomponent axis (IPCA I and IPCA II) were significant (p

A Bayesian procedure was used to estimate linear reaction norms (i.e. individual G × E plots) on 297 518 litter size records of 121 104 sows, daughters of 2040 sires, recorded on 144 farms in North and Latin America, Europe, Asia and Australia. The method allowed for simultaneous estimation of all parameters involved. The analysis was carried out on three subsets, comprising (i) parity 1 records of 33 641 sows of line B, (ii) all parity records of 52 120 sows of line B and (iii) all parity records of 121 104 sows of lines A, B and A × B. Estimated heritabilities ranged from 0.09 to 0.10 (smallest to largest subset) for the intercept of the reaction norms, and were 0.15, 0.08 and 0.02 (ditto) for the slope. Estimated genetic correlations between intercept and slope were −0.09, +0.26 and +0.69 (ditto). The three subsets therefore showed a progressively lower genetic component to environmental sensitivity, and progressively less re-ranking of genotypes across the environmental (herd–year–season) range. In a genetic evaluation that does not include reaction norms in the statistical model, part of the G × E effect remains confounded with the additive genetic effect, which may lead to errors in the estimates of the additive genetic effect; the reaction norms model removes this confounding. The intercept estimates from the largest data subset show correlations with litter size estimated breeding values (EBV) from routine genetic evaluation (without reaction norms included) of 0.78 to 0.85 for sows with one to seven litter records, and 0.75 for sires. Hence, including reaction norms in genetic evaluation would increase the reliability of the EBV of young selection candidates without own performance or progeny data by considerably more than 100 × (1/0.75−1) = 33%. Reaction norm slope estimates turn out to be very demanding statistics; environmental sensitivity must therefore be classified as a ‘hard-to-measure’ trait.

O objetivo deste trabalho foi avaliar a adaptabilidade e a estabilidade da produtividade de grãos de 20 genótipos de feijão-caupi de porte semi-ereto, utilizando o modelo de efeitos aditivos principais e interação multiplicativa. Os ensaios foram conduzidos em 16 ambientes da Região Nordeste do Brasil. Os efeitos de genótipos, ambientes e da interação genótipo x ambiente, e os três primeiros eixos da análise de componentes principais (ACP) foram significativos. Os dois primeiros eixos da ACP explicaram juntos 55,11% da soma de quadrados da interação, correspondendo a 83,20% do padrão da interação genótipo x ambiente. As linhagens TE-97-321G-4, EVX-92-49E e EVX-63-10E apresentaram alta adaptabilidade, mas somente a última foi altamente previsível. A cultivar BRS Guariba e as linhagens EVX-92-49E e TE97-321G-4 expressam melhor potencial genético em ambientes de alta produtividade.The objective of this work was to evaluate the adaptability and the stability of the grain yield of 20 semierect cowpea genotypes, using the additive main effect and multiplicative interaction model. The trials were carried out in 16 environments of the Northeast Region of Brazil. The genotypes, environments and genotype x environment interaction, as well as the first three axes of the principal components analysis (PCA) were significant. The first two axes of the PCA explained 55.11% of the sum of squares of the genotype x environment interaction, corresponding to 83.20% of the pattern of genotype x environment interaction. TE97-321G-4, EVX-92-49E and EVX-63-10E lines were highly adaptable, but only the last one was highly predictable. BRS Guariba cultivar as well as EVX-92-49E and TE97-321G-4 lines best express their genetic potential in environments of high yield.

Prediction of nutrient partitioning is a long-standing problem of animal nutrition that has still not been solved. Another substantial problem for nutritional science is how to incorporate genetic differences into nutritional models. These two problems are linked as their biological basis lies in the relative priorities of different life functions (growth, reproduction, health, etc.) and how they change both through time and in response to genetic selection. This paper presents recent developments in describing this biological basis and evidence in support of the concepts involved as they relate to nutrient partitioning. There is ample evidence that at different stages of the reproductive cycle various metabolic pathways, such as lipolysis and lipogenesis, are up or down regulated. The net result of such changes is that nutrients are channelled to differing extents to different organs, life functions and end-products. This occurs not as a homeostatic function of changing nutritional environment but rather as a homeorhetic function caused by the changing expression of genes for processes such as milk production through time. In other words, the animal has genetic drives and there is an aspect of nutrient partitioning that is genetically driven. Evidence for genetic drives other than milk production is available and is discussed. Genetic drives for other life functions than just milk imply that nutrient partitioning will change through lactation and according to genotype – i.e. it cannot be predicted from feed properties alone. Progress in describing genetic drives and homeorhetic controls is reviewed. There is currently a lack of good genetic measures of physiological parameters. The unprecedented level of detail and amounts of data generated by the advent of microarray biotechnology and the fields of genomics, proteomics, etc. should in the long-term provide the necessary information to make the link between genetic drives and metabolism. However, gene expression, protein synthesis etc, have all been shown to be environmentally sensitive. Thus, a major challenge in realising the potential afforded by this new technology is to be able to be able to distinguish genetically driven and environmentally driven effects on expression. To do this we need a better understanding of the basis for the interactions between genotypes and environments. The biological limitations of traditional evaluation of genotype × environment interactions and plasticity are discussed and the benefits of considering these in terms of trade-offs between life functions is put forward. Trade-offs place partitioning explicitly at the centre of the resource allocation problem and allow consideration of the effects of management and selection on multiple traits and on nutrient partitioning.

Dados de 4.959 lactações de 2.414 vacas da raça Pardo-Suíça, filhas de 70 reprodutores, distribuídos em 51 rebanhos, foram utilizados para se estimar o componente de variância para a interação reprodutor x rebanho das produções de leite e de gordura e verificar o efeito desta interação sobre a avaliação genética dos reprodutores, por meio de modelos que diferiam na presença e ausência do termo de interação. As produções de leite e de gordura foram ajustadas para duas ordenhas diárias, 305 dias de lactação e idade adulta da vaca. O teste da razão de verossimilhança foi utilizado na verificação da efetividade da inclusão da interação no modelo. As médias das produções de leite e de gordura foram 6085,79 ± 1629,73 kg e 225,61 ± 60,44 kg, respectivamente. A proporção da variância total decorrente da interação reprodutor x rebanho foi 0,4%, para a produção de leite, e 1%, para a produção de gordura. A estimativa de herdabilidade foi 0,38, para a produção de leite, utilizando-se ambos os modelos, e reduziu de 0,40 para 0,39, para a produção de gordura, quando o modelo com interação foi considerado. A função de verossimilhança aumentou significativamente com a inclusão da interação no modelo. A correlação de Spearman foi próxima de um para ambas as características, quando todos os reprodutores foram considerados. Houve redução de 1% na estimativa de acurácia dos valores genéticos preditos para ambas as características, porém, a correlação de Pearson estimada entre as acurácias obtidas para cada modelo estudado foi próxima à unidade. A interaçãoreprodutor x rebanho não afetou as estimativas de componentes de variâncias genética e residual e a ordem de classificação dos reprodutores para ambas as características.Data comprising 4,959 lactations of 2,414 Brown-Swiss cows, daughters of 70 sires, from 51 herds, were used to estimate the variance component for sire x herd interaction on milk and fat yields and to verify the effect of this interaction on sire genetic evaluation, using the models that differed in the presence or not of the interaction term. The milk and fat yields were adjusted for two milkings, 305 days of lactation and age cow. Likelihood ratio test was used to verify the effectiveness of including a sire x herd interaction effect in the model. Averages for milk and fat yields were 6085.79 ± 1629.73 kg and 225.61 ± 60.44 kg, respectively. The proportion of the phenotypic variance due to sire x herd interaction was 0.4% for milk yield and 1% for fat yield. The heritability estimate was 0.38 to milk yield, using both models, and decreased from 0.40 to 0.39 for fat yield, when the model with interaction effect was considered. The likelihood function increased significantly with the inclusion of interaction in the model. The Spearman correlation was close to one for both traits, when all sires were considered. There was reduction of 1% in the estimate of accuracy of the breeding values for both traits, however the Pearson correlation estimated among the accuracy obtained for each model was close to one. No effects of sire x herd interaction on estimates of genetic and residual variance components, breeding values magnitude and sire order classification, for both traits, were observed.

Objetivou-se com este trabalho foi avaliar a adaptabilidade e estabilidade de cultivares de alfafa cultivadas em diferentes regiões do Estado de Minas Gerais (Zona da Mata, Zona Metalúrgica e Sul de Minas), quanto à produção de matéria seca de forragem. O delineamento experimental utilizado foi o de blocos casualizados, com três repetições. Foi avaliada a produção de matéria seca de 27 cultivares de alfafa no período de 1995 a 1998. O estudo da adaptabilidade e estabilidade foi realizado por meio das metodologias de Eberhart & Russell (1966) e Lin & Binns (1988). Houve diferenças significativas (P < 0,01) entre as cultivares, os ambientes e a interação cultivar x ambiente, indicando que as cultivares apresentaram desempenho diferenciado diante das variações ambientais. Constatou-se que as cultivares que apresentaram as maiores produções de matéria seca, foram as de maior adaptabilidade e estabilidade pelo método de Lin & Binns. As cultivares Crioula e P-30 são recomendadas para cultivo no Estado de Minas Gerais.The objective of this experiment was to evaluate the adaptability and stability of forage dry matter production of alfalfa cultivars in three different regions in the State of Minas Gerais (Mata, Metalurgica and South). Twenty-seven cultivars of alfalfa were evaluated between 1995 and 1998 using randomized block design with three replications. Adaptability and stability were evaluated using Eberhart & Russel (1966) and Lin & Binns (1988) methodologies. Significant differences (P < .01) among cultivars, environments and the cultivar x environment interactions were observed, showing that cultivars performance is affected by environment. Cultivars with highest dry matter production showed the best adaptability and stability. Cultivars Crioula and P-30 should be recommended to be used in the State of Minas Gerais.

The paper presents an overview of research findings on influence of family environment, especially parental behaviour, on child's development. Contemporary authors question early socialization researchers' claims that family characteristics and parental behaviour have important influence on behaviour of their children. Later researchers examined the size and durability of possible effects of family environment on child development. In addition, they focused on establishing whether it is actually the parental behaviour that influences child's development or, on the contrary, parental behaviour represents mainly a reaction to child's characteristics. Behaviour genetic studies have provided evidence that many traditional measures of family environment, including measures of parental behaviour, show genetic influence, thus reflecting genetically influenced child characteristics. Behaviour geneticists also suggest that environmental influences on child (personality) development include predominantly non-shared environment, i.e. individual child's specific experiences, his/her own perceptions and interpretations of objectively same events. Based on empirically determined significant genetic effects on most behavioural traits and inconclusive results of studies on effects of family environment on child development some authors believe that it is not the parents, but rather genetic factor and/or peers who have the key role in child development. With respect to findings of behaviour genetics numerous recent studies of relations between family environment and child development involve child specific measures of (extra)familial environment and examine the interactions between characteristics of an individual and those of his/her environment.

O objetivo deste trabalho foi comparar dois métodos de regressão empregados para avaliar a estabilidade fenotípica em plantas de cana-de-açúcar, o linear, de Cruz et al., e o não-linear, de Toler & Burrows. Utilizaram-se as informações do ensaio de caracterização de 1994 do programa de melhoramento genético da Copersucar, compreendendo 13 locais e 20 genótipos de cana-de-açúcar no Estado de São Paulo. Os resultados permitiram concluir que ambos os modelos se ajustaram satisfatoriamente aos dados. As estimativas da qualidade ambiental pelos dois modelos mostraram diferenças entre seus valores, porém foram concordantes para inferir sobre os melhores e piores ambientes. Ao classificar os genótipos com base na produtividade e no padrão de resposta, no entanto, apenas dez foram coincidentes nos dois métodos. As vantagens estatísticas do método não-linear torna-o recomendável para pesquisa sobre estabilidade.The purpose of this work was to compare the regression methods used for evaluating phenotypic stability in plants. The methods of Cruz et al. based on a linear model and of Toler & Burrows based on a non-linear model were considered. Data of the sugarcane 1994 characterization trial coordinated by the genetic improvement program of Copersucar were used. Experiments were set up in 13 locations of the State of São Paulo, in Brazil for evaluation of 20 sugarcane genotypes. The fitting of the models to the data was obtained for both methods. Measures of environmental quality were numerically different but agreed in general terms for the ranking of locations. However, when genotypes were classified on the bases of yield and pattern of response only ten coincided for both methods. The statistical advantages of the non-linear model makes it recommendable for studies on stability.

O objetivo deste trabalho foi estudar o desempenho produtivo, adaptabilidade e estabilidade fenotípica de seis genótipos de tomateiro na região de Marília, SP. Os experimentos foram conduzidos em nove ambientes (seis sob condições de cultivo protegido e três sob condições de céu aberto), com seis genótipos (Carmen, Diva, Donador, Graziela, Vita e HE-295), em blocos casualizados, com quatro repetições. Ocorreram diferenças significativas entre ambientes, e a média geral dos cultivos protegidos superou a dos cultivos a céu aberto quanto à produtividade, apesar de a média geral dos cultivos a céu aberto ser superior quanto ao peso médio de frutos. As cultivares, à exceção de HE-295, demonstraram alta estabilidade, merecendo destaque as cultivares Carmen, Donador e Vita, que tiveram rendimento médio superior ao da média geral, adaptabilidade geral e comportamento previsível em todos os ambientes estudados. Quanto ao peso médio dos frutos, as cultivares Diva e Vita foram as únicas que mostraram ampla adaptabilidade a todos os ambientes, comportamento previsível, além de apresentarem peso médio do fruto superior ao da média geral.The objective of this work was to evaluate productivity, adaptability and phenotypic stability of six tomato genotypes in Marília, SP, Brazil. The experiments were carried out at nine environments (six of them under conditions of protected cultivation and three under open air conditions), with six genotypes (Carmen, Diva, Donador, Graziela, Vita and HE-295), in a randomized block design, with four replications. There were significant differences among environments, independent of cultivation system. General average of protected cultivations overcame free cultivations considering yield, although the general average of free cultivations was overcame for mean fruit weights. All genotypes, except 'HE-295', showed high stability, with prominence for cultivars Carmen, Donador and Vita, which showed higher mean yield, and general adaptability and stability in all environments studied. For mean fruit weights, cultivars Diva and Vita were the only ones that showed wide adaptability for both environments and highly predictable behavior, with mean fruit weights superior to general average.