RESUMO -Foram avaliados 15 descritores reprodutivos, 22 vegetativos e 21 agronômicos, em que os agronômicos compreenderam sete descritores para a avaliação anual, sete descritores para a avaliação de inverno e sete descritores para a avaliação de verão, com o objetivo de selecionar os melhores descritores botânico-agronômicos para caracterizar acessos das espécies Paspalum guenoarum e Paspalum plicatulum. Utilizou-se a análise de componentes principais para descartar os descritores considerados redundantes ou não-discriminantes. Este método permitiu redução de 53, 68 e 43% dos descritores reprodutivos, vegetativos e agronômicos, respectivamente, do conjunto inicialmente considerado. Foi possível selecionar, por intermédio desta técnica, oito descritores, considerados mais importantes na descrição da variabilidade presente na coleção de acessos do germoplasma estudado.Palavras-chave: acessos, análise de componentes principais, germoplasma, seleção de descritores Selection of Descriptors for Paspalum sp. Germplasm Characterization by Means of Principal ComponentsABSTRACT -Fifteen reproductive, 22 vegetative and 21 agronomic descriptors were evaluated, the agronomic ones comprised seven descriptors for annual, winter and summer evaluations, respectively, with the objective to select the most appropriate descriptors for characterization of Paspalum guenoarum and Paspalum plicatulum. Principal components analysis was used to discard redundante or non-discriminative descriptors. The principal component analysis allowed a reduction of 53, 68 and 43%, respectively, in the number of initial descriptors considered. By means of this technique, it was possible to select eight descriptors, considered the most important descriptors to identify the genetic variability in this germplasm collection.

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Lack of cultivar adapted to the planting area, as the ideal harvest period undertakes the productive potential of cassava. The study was conducted to evaluate the influence of different harvest seasons on total production of fresh and dry weight of four cassava cultivars. The used cultivars were: Branca de Santa Catarina (BSC), IAC 13, IAC 14-18 and Fiber that they were planted on 09/20/11 at the headquarters of the Regional Center Valley Paranapanema Paulista Agency for Agribusiness Technology (APTA), in Assis, São Paulo. The experimental design was completely randomized in 4x6 (four cultivars and six harvest seasons) factorial schemes with four replicates, being 4, 8, 12, 16, 20 and 24 months after planting (MAP) the harvest season, totaling 24 treatments and 48 installments. The total production of fresh biomass (FB) and dry matter (DM) in tons per hectare of 12 plants per harvest season was evaluated. Regarding the production of FB as DM among cultivars was not observed significant differences between them. However, the cultivars showed accumulation of FB linearly. The best time to harvest in order to higher accumulation of DM occurred at 12 and 24 months, corresponding to the end of the first and second round of cassava cultivation, respectively.

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