ABSTRACT: Studies on the improvement of hops (Humulus lupulus) in Brazil are recent and seek to establish self-sufficiency in production. Knowledge of the variability of genotypes available in the country is of fundamental importance for the development of a hop improvement program. The objective of the research was to characterize and identify hop parents with agronomic and brewing potential for the Planalto Catarinense region, Brazil. The randomized block design arranged in a 3x4 factorial scheme was used with 12 treatments: (Factor 1: three years of cultivation (2019, 2020 and 2021) and combined with factor: four genotypes (Cascade, Chinook, Columbus and Hallertau). The characters evaluated were fresh mass of plants (MFP, g), green mass of cones (MTV, g), dry mass of cones (MSC, g), alpha-acid content (ALFA, %) and production (PROD, g per plant). The Hallertauer genotype showed better performance and differentiated behavior for the characters of fresh mass of plants, dry mass of cones and production, when compared to the others. Thus, from these results it was observed that there is variation available for the genetic improvement of hops for these characters, a factor that will allow obtaining productive gains in the development of new cultivars, based on this promising genotype.

RESUMO: Os estudos visando o melhoramento de lúpulo (Humulus lupulus) no Brasil são recentes e buscam estabelecer a autossuficiência da produção. O conhecimento da variabilidade dos genótipos disponíveis no país é de fundamental importância para o desenvolvimento de um programa de melhoramento de lúpulo. O objetivo do trabalho foi identificar genitores de lúpulo com potencial agronômico e cervejeiro para o Planalto Catarinense, Brasil. Foi utilizado o delineamento em blocos casualizados em esquema fatorial 3x4 com 12 tratamentos: Fator 1: três anos de cultivo (2019, 2020 e 2021) e combinado com o fator 2: quatro genótipos (Cascade, Chinook, Columbus e Hallertau). Os caracteres avaliados foram a massa fresca de plantas (MFP, g), massa verde de cones (MTV, g), a massa seca de cones (MSC, g), os teores de alfa-ácidos (ALFA, %) e a produção (PROD, g per planta). O genótipo Hallertauer demonstrou melhor desempenho e comportamento diferenciado para os caracteres de massa fresca de plantas, massa seca de cones e produção, quando comparado aos demais. Assim, a partir destes resultados observou-se que, existe variação disponível ao melhoramento genético do lúpulo para esses caracteres, fator que permitirá obter ganhos produtivos no desenvolvimento de novas cultivares, a partir deste genótipo promissor.

ABSTRACT: Hops (Humulus lupulus L.) are of particular economic importance in the highlands of the state of Santa Catarina, Brazil, by virtue of the number of breweries in the region. However, since the cultivars currently available in the country present poor qualitative attributes and low cone productivity, there is considerable demand for improved genotypes. The results of diallel crossing experiments help to increase our understanding of inheritance processes and the mechanisms controlling the transfer of alleles with additive or non-additive action, thereby allowing breeders to explore the benefits of heterosis. The present study evaluated the general and specific combining abilities (GCA and SCA, respectively) of four hop genotypes and to obtain F1 hybrids with agronomic traits superior to those of the parents and the ability to adapt to the environmental conditions in the Santa Catarina highlands. Partial diallel crosses were performed using a randomized complete block design involving 14 treatments, namely two male parents (Cascade and Hallertauer), four female parents (Columbus, Chinook, Cascade and Hallertauer) and eight hybrid combinations, with three repetitions each. The results showed that SCA was the predominant controlling mechanism for the manifestation in hybrids of the traits length of the lateral branch, height of insertion of the first cone, plant green mass and cone productivity. Some parental combinations also exhibited high GCA, indicating the presence of favorable alleles with additive action. The best combination was Hallertauer × Cascade, a finding that highlights the importance of choosing parents from different gene pools (American × European) to obtain genetically enhanced hybrids.

RESUMO: O lúpulo (Humulus lupulus L.) possui grande importância econômica no planalto serrano do estado de Santa Catarina, uma vez que existem inúmeras cervejarias nesta região do Brasil. Como as cultivares disponíveis no país carecem de bons atributos qualitativos e apresentam baixa produtividade de cones, existe grande demanda por genótipos melhorados. Os resultados de experimentos de cruzamento dialélico aumentam a compreensão dos processos de herança e dos mecanismos de controle associados à transferência de alelos com ação aditiva ou não aditiva, permitindo assim que os geneticistas explorem os benefícios da heterose. Os objetivos deste estudo foram avaliar as capacidades de combinação geral e específica (CGC e CEC, respectivamente) de quatro genótipos de lúpulo e obter híbridos F1 com características agronômicas superiores às dos genitores e habilidade para se adaptar às condições ambientais do planalto catarinense. Os cruzamentos dialélicos parciais foram realizados em delineamento de blocos casualizados envolvendo 14 tratamentos, i.e. dois genitores masculinos (Cascade e Hallertauer), quatro genitores femininos (Columbus, Chinook, Cascade e Hallertauer) e oito combinações híbridas, com três repetições cada. Os resultados mostraram que a CEC dos genitores foi o mecanismo de controle predominante para a manifestação nos híbridos das características comprimento do ramo lateral, altura de inserção do primeiro cone, massa verde da planta e produtividade de cones. Algumas combinações entre genitores também manifestaram CGC elevada, indicando a presença de alelos favoráveis com ação aditiva. A melhor combinação foi Hallertauer × Cascade e essa descoberta demonstra a importância da escolha de genitores originários de diferentes grupos genéticos (Americano × Europeu) para obter híbridos geneticamente melhorados.

RESUMO: Este estudo teve como propósito compreender como os componentes genéticos envolvidos no caráter tempo de cocção se comportam desde as primeiras gerações de autofecundação até a formação das linhagens. Dois cruzamentos dirigidos foram utilizados dando origem a progênies segregantes em distintos níveis de heterozigose (F2, F3, F8e F9). O tempo de cocção foi determinado pelo cozedor de Mattson. Foram estimados os componentes de variância com base no modelo misto e as frações aditiva e não aditiva pelo método de Cockerham. Adicionalmente, foram realizados testes de escala incluindo a endogamia como parâmetro genético. Independente do modelo hierárquico de variância entre famílias segregantes testado, o componente de dominância foi no mínimo duas vezes superior a fração aditiva da variância. Este fato também foi corroborado com os testes de escala, com predominância do componente de dominância sobre o componente aditivo, principalmente no cruzamento entre grupos comerciais diferentes, carioca x preto, no qual o componente aditivo foi nulo. Além disso refletiu no menor coeficiente de herdabilidade no sentido amplo, considerando a maior influência de causas não genéticas. O papel da dominância sobre o tempo de cocção implica na necessidade de selecionar os genótipos em estágios avançados de endogamia, porém, a variação deve estar representada nesta fase por intermédio da escolha de genitores com tempo de cocção menor.

ABSTRACT: This study aimed to understand how the genetic components involved in cooking time behave from the first generations of self-fertilization to the formation of lines. Two targeted crosses were used, resulting in segregating progenies at different heterozygosity levels (F2, F3, F8, and F9). Cooking time was determined using the Mattson cooker. Variance components were estimated based on the mixed model, and additive and non-additive fractions were calculated using the Cockerham method. Additionally, scale tests were performed, including inbreeding as a genetic parameter. Regardless of the hierarchical variance model in the segregating families tested, the dominance component was at least twice as high as the additive variance fraction. This was also corroborated by the scale tests, with a predominance of the dominance over the additive component, primarily in the cross between different commercial groups (carioca x black), where the additive component was zero. Additionally, this resulted in a lower broad-sense heritability coefficient, indicating a greater influence of non-genetic causes. The role of dominance in cooking time implies the need to select genotypes at advanced inbreeding stages, but variation should be represented at this stage by selecting parent plants with shorter cooking times.

Abstract: The breeding of Physalis peruviana is incipient in Brazil and is shown to be the most promising alternative for the development of productive genotypes with fruit quality. Therefore, the objective was to evaluate the combining ability between inbred lines of P. peruviana, thus indicating the selection of hybrids with fruit quality. Therefore, four populations from different origins were selfed for three generations and crossed in controlled hybridizations, resulting in 28 P. peruviana populations. The hybrid in relation to the parent performance, based on the effects of general and specific combining ability, was compared in a full diallel mating design (Griffing Method 1). In the analysis of variance, the factor genotype was partitioned into the following causes of variation: i) parents and F1 hybrids, ii) selfed generations and iii) Genotype × environment (GE) interaction. There were significant differences between Parents and F1 hybrids for the trait fruit polar diameter. Still, the interaction between specific combining ability x environment and, reciprocal effect x environment, was significant. However, for the Xanxerê environment, there was a reduction of approximately 3.0 mm in the polar diameter of the fruit in the hybrid Colombia x Peru and a reduction of 4.5 mm for the reciprocal (Peru x Colombia). In the comparison of the selfed generations S0 with S1, the fruit weight of the Lages population decreased by 0.380 g. There was also a reduction of 974.5 kg.ha-1 in the fruit yield of the Peruvian population. Thus, the performance of the P. peruviana populations in hybrid combinations is unpromising, indicating the existence of only one P. peruviana gene pool, with a restricted genetic basis.

Resumo: O melhoramento de Physalis peruviana é incipiente no Brasil e mostra-se como a alternativa mais promissora no desenvolvimento de genótipos produtivos e com qualidade de fruto. Sendo assim, o objetivo foi avaliar a capacidade de combinação entre linhagens endogâmicas de P. peruviana, indicando, assim, híbridos comqualidade de fruto. Para tanto, quatro populações de distintas origens (Colômbia, Lages,Caçador, Peru)foram submetidas a três gerações de autofecundação e a hibridação, totalizando28 genótipos. Utilizou-se um esquema de dialelo completo (Método 1 de Griffing) a fim de comparar o desempenho dos híbridos em relação aos genitores, com base nos efeitos dacapacidade geral e da capacidade específica de combinação. Os experimentos foramconduzidos em dois locais (Lages-SC e Xanxerê-SC), sob um delineamento de blocoscasualizados, com três repetições. Na análise de variância, o fator genótipo foi decomposto nasseguintes causas de variação: i) genitores e híbridos F1’s, ii) gerações de autofecundação e iii) interação genótipo x local. Houve diferenças significativas entre Genitores e híbridos F1’s parao caráter diâmetro polar do fruto. Foram observados valores significativos para adecomposição da interação: Capacidade específica x Local e Recíproco x Local. Porém, para oambiente de Xanxerê, houve redução de aproximadamente 3,0 mm no diâmetro polar do fruto,no híbrido Colômbia x Peru, e redução de 4,5 mm, para o recíproco (Peru x Colômbia). Comrelação às autofecundações, na comparação S0 vs. S1 para as populações Lages e Peru,houve redução na massa de frutos (0,380 g) e no rendimento de frutos (974,5kg.ha-1). Porém,de maneira geral, a qualidade de fruto não foi afetada em virtude dasautofecundações. As populações não manifestam desempenho promissor quando em combinações híbridas,revelando a existência de apenas um pool gênico de P. peruviana de restritabase genética.

ABSTRACT The knowledge about the genetic behavior of roots can be the solution to the main climatic problems and the key for increased production of agricultural crops. In inheritance studies, breeders usually conduct crosses between contrasting individuals to obtain a significant fraction of the genetic variance. To determine genetic parameters in beans from crosses within and between Middle American and Andean gene groups, 64 populations (breeders, F1 and F2) were evaluated under field conditions for the trait root distribution. Crosses between Middle American and Andean gene groups revealed significant estimates for genetic parameters (genetic variance, heritability, and average degree of dominance) compared to intra-pool crosses. However, only 4% of all hybrid combinations evaluated (F1 and F2) showed significant effects when compared to fixed populations (parents). Coupled with the insignificant number of progenies different from the parents, the differences detected revealed inferior performance, compared to the parents. The joining of alleles with identical provenance may be the main cause of the observed effects. The breeding strategy for root distribution should consider more divergent parents.

RESUMO: Physalis peruviana L. (fisális) apresenta grande potencial econômico devido ao sabor diferenciado de seus frutos. A produtividade dos pomares brasileiros é baixa em função do número limitado de variedades ou cultivares disponíveis. O principal entrave na seleção de genótipos superiores é a falta de informação sobre a variabilidade genética dentro e entre as populações de fisális e, possivelmente, a base genética limitada das mesmas, que pode ser explicada pelos processos evolutivos, de domesticação e de seleção das populações naturais ou artificiais. A fisális cultivada atualmente no Brasil é tetraploide e tal poliploidia pode ter levado ao isolamento reprodutivo da espécie, o qual impede a ocorrência de hibridação intraespecífica. As populações cultivadas provêm de um pool genético comum e, além disso, sofreram um longo processo de domesticação e seleção realizadas empiricamente pelos agricultores. Porém, na Colômbia e em outros países andinos existem populações silvestres que exibem diversidade genética que, embora sejam fundamentais para a conservação da espécie, apresentam baixo potencial para o desenvolvimento de genótipos com características agronômicas superiores. A fim de criar e ampliar a variabilidade genética de fisális, os melhoristas tem empregado várias estratégias incluindo a indução de mutação, a duplicação cromossômica e a hibridação inter e intraespecífica. Além disso, a produção de linhagens duplo-haploides a partir da cultura de anterasin vitro vem demonstrando bons resultados para a seleção de híbridos. Os genótipos mutantes e/ou híbridos obtidos através dos métodos citados em associação com os de seleção genômica ampla podem gerar cultivares com características agronômicas superiores.

ABSTRACT: Physalisperuviana L. (physalis) has significant economic potential by virtue of the unique flavor of its fruit. However, the productivity of Brazilian plantations is low because of the limited number of varieties or cultivars available. The main obstacle in the selection of superior genotypes is the lack of information about genetic variability within- and between- populations and limited genetic basis that has likely resulted from evolutionary, domestication and selection processes of the natural or artificial populations. Physalis currently cultivated in Brazil is tetraploid, and such polyploidy may have led to the reproductive isolation of the species, preventing the occurrence of intraspecific hybridization. Moreover, cultivated populations derive from a common gene pool and have undergone a long process of domestication and selection carried out empirically by farmers. In Colombia and other Andean countries there are wild populations that exhibit genetic diversity which; although, fundamental for the conservation of the species, have low potential for the development of genotypes with superior agronomic traits. In order to create and expand the genetic variability of physalis, breeders have employed various strategies including induction of mutation, chromosome duplication, and interspecific and intraspecific hybridization. Furthermore, the production of double haploid lines from in vitro anther cultures has shown good results in the selection of hybrids. The mutant genotypes and/or hybrids obtained using these methods in association with those of wide genomic selection can generate cultivars with superior agronomic traits.

Abstract The objective of this work was to evaluate root phenotyping methods and the ideal phenological stage to quantify the root system of fixed and segregating common bean populations, in order to select superior genotypes. The experiment was carried out in two municipalities in the state of Santa Catarina, Brazil, and the treatments consisted of six genotypes, the Shovelomics and WinRHIZO root phenotyping methods, and the V4-4, R6, and R8 phenological stages. The simple lattice experimental design was used to evaluate the following variables: basal root angle, vertical root length, left and right horizontal root length, total root length, projected area, and root average volume and diameter. For all variables, there was a significant interaction between phenotyping methods and phenological stages, showing their influence on root system evaluation. The Shovelomics and WinRHIZO phenotyping methods are efficient in quantifying the root system of common bean plants and show specificity for phenological stages, regardless of the genotype. The quantification of the root system of fixed and segregating genotypes is analogous in both methods. The Shovelomics method is more efficient in evaluating the root system of common bean at the R8 stage, and the WinRHIZO method, at the R6 stage.

Resumo O objetivo deste trabalho foi avaliar métodos de fenotipagem de raízes e o estádio fenológico ideal para quantificação do sistema radicular de populações fixas e segregantes de feijoeiro, para selecionar genótipos superiores. O experimento foi realizado em dois municípios do estado de Santa Catarina, Brasil, e os tratamentos consistiram em seis genótipos, nos métodos de fenotipagem Shovelomics e WinRHIZO, e nos estádios fenológicos V4-4, R6 e R8. O delineamento experimental látice simples foi utilizado para avaliar as seguintes variáveis: ângulo de raiz basal, comprimento vertical das raízes, comprimento horizontal esquerdo e direito das raízes, comprimento total das raízes, área projetada, e volume e diâmetro médio de raízes. Para todas as variáveis, houve interação significativa entre os métodos de fenotipagem e os estádios fenológicos, o que mostra a influência desses na avaliação do sistema radicular. Os métodos de fenotipagem Shovelomics e WinRHIZO são eficientes para a quantificação do sistema radicular do feijoeiro e apresentam especificidade para o estádio fenológico, independentemente do genótipo. A quantificação do sistema radicular de genótipos fixos e segregantes é análoga em ambos os métodos. O método Shovelomics é mais eficiente para avaliar o sistema radicular do feijoeiro na fase R8, e o método WinRHIZO, na fase R6.

Abstract According to literature, the apple cultivar SCS425 Luiza is a hybrid of Imperatriz♀ and Cripps Pink♂; however, molecular analysis of gametophytic self-incompatibility alleles showed the presence of an unexpected allele in SCS425 Luiza. This raised doubts about the fidelity of the pedigree. Thus, this study aimed to investigate the real genealogy of the SCS425 Luiza cultivar via fingerprint analysis. A total of 19 pairs of SSR primers covering 12 of the 17 chromosomes were used. ‘Imperatriz’ was tested as the female parent, and either ‘Cripps Pink’ or ‘Baronesa’ was tested as the presumed male parents. The results excluded ‘Cripps Pink’ as the male parent because most of the markers showed alleles of exclusion with Likelihood ratio (LR) value equal to zero. In contrast, when Baronesa was tested as the male parent, all alleles followed the expected segregation with very high LR values (>10.000). Therefore, it is concluded that the correct genealogy of the SCS425 Luiza cultivar is Imperatriz♀ and Baronesa♂.

RESUMEN La creciente demanda por cultivares de cebolla de baja pungencia ha abierto nuevos nichos de mercado. El objetivo de este estudio fue caracterizar grupos heteróticos de cebolla para el desarrollo de cultivares híbridos con baja pungencia. Se realizó un experimento de campo con un diseño de bloques al azar con dos factores (genotipo y fertilización) dispuestos en parcelas divididas en Ituporanga-SC (Brasil), en 2019. Las parcelas correspondieron a dos niveles de fertilización (con y sin azufre) y las subparcela a vinteseis genotipos de cebolla, considerando germoplasma procedente de líneas androestéreles-LA y mantenedoras-LB, poblaciones avanzadas y cultivares. Los bulbos fueron evaluados por las características: ácido pirúvico (indicador de pulgencia), contenido de azufre y rendimiento de bulbo. Los genotipos revelaron un comportamiento diferencial según el nível de fertilización adoptado. En la condición sin azufre cuatro grupos heteróticos fueron identificados, los cruzamientos LA11 × LB24 y LA15 × LB19 pueden generar variación genética y la respectiva selección negativa para la pungencia y positiva para la productividad de bulbos.

ABSTRACT The growing demand for low-pungency cultivars onion has opened new market niches. The objective of this study was to characterize heterotic onion groups to develop low-pungency hybrid cultivars. A field experiment with a randomized block design and two factors (genotype and fertilization) arranged in split plots was carried out in Ituporanga-SC (Brazil), in 2019. The plots corresponded to two fertilization levels (with and without sulfur), and the subplots corresponded to 26 onion genotypes, where the germplasm was derived from different (male-sterile-LA and maintainer-LB) lines, advanced populations and cultivars. The bulbs were evaluated for the following traits: pyruvic acid (indicator of pungency), sulfur content and bulb yield. The genotype performance differed according to the fertilization level. In the sulfur-free treatments, four heterotic groups were identified. The genetic variation in the crosses LA11 × LB24 and LA15 × LB19 could be exploited for negative selection for pungency and positive selection for bulb yield.

Abstract ‘Caviano’ is a black bean cultivar recommended for Santa Catarina, for being highly adaptable to the main grain-producing regions of the state (mean grain yield 2315 kg ha-1). Compared to previously released cultivars, Caviano has a larger root system and desirable characteristics for mechanical harvesting.

ABSTRACT. Heterosis has been one of the most studied phenomena since genetic studies were conceived. Knowledge of this phenomenon for the root distribution trait in beans (Phaseolus vulgaris L.) can favour the development of genotypes that are more tolerant to abiotic stresses. This study aimed to verify the occurrence of heterosis for the root distribution trait in hybrid F1 populations of common bean derived from crosses within and between gene groups. Thirty-six populations (six parents and 30 hybrids) were evaluated under field conditions in the agricultural years 2016/17 and 2017/18. The root distribution was assessed with the adapted Bohm method. The genotypes responded similarly to environmental changes (absence of an interaction). However, the root distribution differed significantly between the agricultural years. Comparisons between the mean of hybrids from crosses within each gene pool and the mean of parents did not reveal heterosis. The comparisons between gene groups showed significant differences only between BRS Embaixador x IPR Uirapuru, CBS 14 x IPR Uirapuru, and BAF 53 x IPR Uirapuru and the mean of parents. The absence of heterosis in the root trait can be explained by the degree of kinship between the gene groups, as well as some epistatic interactions.

ABSTRACT Apple orchards require the presence of a different genotype to pollinate the fruit producing cultivar. This is due to the process of gametophytic self-incompatibility present in most species and cultivars of the genus Malus. The fruit producing cultivar and the pollinizer must be genetically compatible to ensure fruit set and symmetrical and adequate fruit formation. The aim of this work was to evaluate five potential pollinizers for the new apple cultivar SCS426 Venice by genotyping the self-incompatibility locus (S-locus) and by controlled pollination in the field. The S-locus was screened using molecular markers and the fertilization capacity was evaluated by monitoring the fruit set after artificial pollination. Three genotypes were identified as semi-compatible (selection 135/140, cultivar SCS433 Felix 3 and SCS425 Luiza) and two as fully compatible (‘SCS431 Felix 1’ and ‘SCS434 Felix 4’) with ‘SCS426 Venice’. Regardless of the level of compatibility, all genotypes tested are efficient for the fertilization of ‘SCS426 Venice’ flowers and can be used as pollinizers in commercial orchards of this cultivar.

Resumo O objetivo deste trabalho foi caracterizar genitores e respectivas populações de macieiras quanto aos alelos S para confirmar sua genealogia e avaliar a eficiência dos marcadores moleculares utilizados. Conjuntos específicos de iniciadores foram utilizados para a identificação dos alelos S via PCR. Foram avaliadas duas populações segregantes do Programa de Melhoramento Genético de Macieira da Epagri resultantes dos cruzamentos entre ‘Fred Hough’ × ‘Monalisa’ e ‘M-11/00’ × ‘M-13/91’. As segregações esperadas são 1:1:1:1 para compatibilidade total e 1:1 para semi-compatibilidade, que pode ser confirmada pelo teste X2. O cruzamento ‘Fred Hough’ (S5S19) × ‘Monalisa’ (S2S10) foi identificado como totalmente compatível, e foram identificados dois triploides entre os híbridos. O cruzamento entre ‘M-11/00’ (S3S19) × ‘M-13/91’ (S3S5) se mostrou semi-compatível baseado nos marcadores moleculares e a segregação dos alelos S nos híbridos foi de 1:1 como esperado. A segregação dos marcadores de DNA para S2, S3, S5, S10 e S19 ocorreu juntamente com seus respectivos alelos S. Dessa forma, a caracterização dos alelos S, além de permitir identificar a compatibilidade entre os genitores, serviu para identificar contaminações em populações segregantes.

Abstract The objective of this study was to characterize the parents and respective populations of apple trees regarding S-alleles to confirm their genealogy and to evaluate the efficiency of the molecular markers used. Sixteen specific sets of primers were used for identification of apple S-alleles by PCR. Two segregating populations of the Epagri Apple Breeding Program resulting from crosses between ‘Fred Hough’ × ‘Monalisa’ and ‘M-11/00’ × ‘M-13/91’ were evaluated. The expected segregations are 1:1:1:1 for full compatibility and 1:1 for semi-compatibility, which can be confirmed by the X2 test. The ‘Fred Hough’ (S5S19) × ‘Monalisa’ (S2S10) cross proved to be fully compatible; and two triploids were identified among the hybrids as well. The ‘M-11/00’ (S3S19) × ‘M-13/91’ (S3S5) cross was characterized as semi-compatible based on DNA markers, and the segregation of the S-alleles in the hybrids was 1:1, as expected. The segregation of the DNA markers occurred together with their respective S-alleles: S2, S3, S5, S10, and S19. Thus, characterization of the S-alleles not only allowed identification of compatibility between parents but also identified contaminations in segregating populations.

ABSTRACT Genetic variability is essential for gains in breeding programs. The cyclic process of progeny recombination is a strategy to raise the chances of selecting better genotype combinations. The objective of this study was to identify superior progenies between common bean genes groups in first recurrent selection cycle for root system traits. Parents of the Andean and Middle American gene groups were hybridized in a complete diallel scheme. Thereafter, the parents and F1 and F2 populations were planted in the field. To establish the base population of recurrent selection (C0), seven segregating populations (F2) with superior performance for root system were selected and intercrossed, resulting in recombinant progenies (C1). To estimate the selection gain, the parents and C0 and C1 genotypes were compared with regard to the following variables: total root length (TRL, cm), projected root area (PRA, cm2), root volume (VOL, cm3) and number of root tips (RT). The difference between genotype combinations indicates the presence of genetic variability and effectiveness of recurrent selection. The mean genetic progress for root system-related traits was 12.9% (TRL), 12.6% (PRA), 12% (VOL) and 11.5% (RT) in the first recombination cycle. The mean phenotypic performance of seven of the C1 progenies exceeded that of their parents for all root system traits. These progenies are promising as base populations of the next selection cycle.

Abstract: The objective of this study was to identify self-incompatibility (S) alleles of advanced breeding selections of apple (Malus × domestica Borkh.). The S-alleles of 42 apple genotypes were analyzed by markers using allele-specific PCR amplification and amplicons digested with restriction endonucleases. Among the screened genotypes were cultivars, advanced selections, and accessions of the Apple Germplasm Bank of Epagri (Caçador, Santa Catarina, Brazil). Two S-alleles were identified in 36 genotypes, and only one S-allele was determined in the other six genotypes. In all, eleven S-alleles were identified among all the genotypes evaluated. The S3 and S5 alleles were most frequent (30.2% and 19.8%, respectively). The identification of S-alleles using molecular markers in important apple tree genotypes is useful for determination of compatible parents for breeding programs.