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ABSTRACT: Andropogon lateralis Nees is a native grass of southern Brazil and is one of the most frequent specie found in native grasslands. The species is widely distributed and has a high degree of phenotypic plasticity, which makes it highly adaptable to different edaphoclimatic conditions and management. This study aimed to evaluate the behavior of twelve ecotypes of A. lateralis, collected in different regions of the state of Rio Grande do Sul and cut to three different heights and subjected to two different defoliation frequencies. From September to February, the ecotypes were evaluated for total dry matter, leaf and stem yields. In addition, total, vegetative and reproductive tillers and plant height were measured. These characteristics are important for the selection of superior genotypes in terms of genetic variability and forage production. Total dry matter and leaf dry matter are characteristics with agronomic importance and they showed the highest correlation (r = 0.77), enabling an indirect selection for one of these characteristics. The natural selection of plants resulted in distinct structural, morphological and productive characteristics with heterogeneity that allows the selection and grouping according to the characteristics, ecotypes with superior agronomic characteristics can be included in breeding programs.

The objective of this study was to analyze the adaptability and the stability in apomictic genotypes of the genus Paspalum across the main characters of forage interest evaluated in different years and locations. The experiment was conducted in the years 2010 and 2011 in the municipalities of Eldorado do Sul and Augusto Pestana, RS, Brazil, in a randomized complete block design with three replications. Analyses of adaptability and stability were calculated by the Traditional and the Eberhart and Russel method. The genotypes of P. guenoarum Baio anda Azulão shows high biomass production but adapted to favorable environments and reduced stability. The genotypes of P. lepton 28C show the total dry mass specific adaptability to unfavorable environment and in the dry leaf adaptability with stability

Os citros apresentam uma taxonomia muito complexa, principalmente com relação ao número de espécies que constituem o gênero Citrus e os gêneros afins. Genótipos classificados como espécies podem ter sido originados por hibridação interespecífica e preservados por meio da embrionia nucelar. O presente trabalho teve como objetivo caracterizar uma população de tangerineiras híbridas oriundas do cruzamento das tangerineiras 'Clementina Fina' (Citrus clementina Hort. ex Tan.), genitor feminino, e 'Montenegrina' (Citrus deliciosa Ten.), genitor masculino, utilizando marcadores do tipo microssatélites (SSR). Com 12 pares de primers, foi possível diferenciar 93 acessos do estudo e agrupar a F1 em indivíduos mais próximos do genitor feminino e do genitor masculino. O PIC (Conteúdo de Informação de Polimorfismo) dos primers variou de 0,27 a 0,65. Toda a progênie do cruzamento entre 'Clementina Fina' e 'Montenegrina' analisada neste estudo é híbrida, e os SSRs foram eficientes para identificar híbridos com maior similaridade genética em relação aos genitores, mostrando a existência de variabilidade genética entre as plantas da população estudada.Citrus have a very complex taxonomy, especially considering the number of species included in genus Citrus and related genera. What is classified as a species may have originated by interespecific hybridization and preserved through nucellar embryony. This research aimed to characterize a population of hybrid tangerines, originated from the cross of 'Clementina Fina' (Citrus clementina Hort. ex Tan.) as female and 'Montenegrina' (Citrus deliciosa Ten.) as male parents, using microsatellite molecular makers. With 12 pairs of primers it was possible to differentiate 93 of the studied accessions and to group F1 individuals nearer to the male or to the female parent. The primers PIC (Polymorphism Information Content) ranged from 0.27 to 0.65. All the analyzed progeny between 'Clementina Fina' and 'Montenegrina' is hybrid, where SSR were efficient in identifying hybrids more similar to the genitors, showing genetic variability among plants of the studied population.

A tangerineira 'Michal' (Citrus clementina x C. tangerina) poderá ser uma boa alternativa ao Rio Grande do Sul como cultivar copa para produção de frutos em época precoce. No entanto, há falta de informações sobre seu comportamento em cultivo nas condições ambientais desse Estado. O objetivo deste trabalho foi avaliar o desenvolvimento das plantas, a produção e a qualidade dos frutos da tangerineira 'Michal' enxertada sobre cinco porta-enxertos: citrangeiro 'Troyer', citrumeleiro 'Swingle', limoeiro 'Cravo', tangerineira 'Sunki' e trifoliata 'Flying Dragon', na Depressão Central do Rio Grande do Sul. Foram avaliados os seguintes parâmetros: a altura das plantas, a circunferência do tronco, a área de projeção da copa (APC), o número e a massa (MF) de frutos produzidos, a relação MF/APC (IP), o teor de sólidos solúveis totais (SST), a acidez total titulável (ATT) e a relação SST/ATT do suco, além do tamanho dos frutos e do rendimento de suco. O citrumeleiro 'Swingle' promoveu bom vigor, boa produção, bom IP, bons níveis de SST e de ATT da 'Michal', enquanto o limoeiro 'Cravo' conferiu bom vigor, boa produção, bom IP e bom tamanho dos frutos, ambos podendo ser indicados como porta-enxertos em pomares de tangerineira 'Michal'.'Michal' tangerine (Citrus clementina x C. tangerina) can be a good choice as canopy for early maturing fruit production in Rio Grande do Sul. The limitation is the lack of information about its performance and management. The aim of this research was to evaluate the development, production and fruit quality of 'Michal' tangerine grafted on five rootstocks: 'Troyer' citrange, 'Swingle' citrumelo, 'Cravo' lemon, 'Sunki' tangerine and 'Flying Dragon' trifoliate orange, in the Depressão Central of Rio Grande do Sul. The following variables were evaluated: plant height; trunk circumference; canopy projection area (APC); produced fruit number and weight (MF); MF/APC relation (IP); juice total soluble solids (SST) and total titrable acidity (ATT); fruit size and juice content. 'Swingle' citrumelo provided good vigor, yield, IP, SST and ATT for 'Michal', while 'Cravo' lemon induced good vigor, yield, IP and fruit size. Both are good recommendations as rootstock for orchards of 'Michal'.