No abstract

The objective was to evaluate the adaptability and yield stability of different peach rootstock genotypes in subtropical climate in an experiment in Chapecó, Santa Catarina, Brazil. Twenty-one rootstocks under the scion cultivar 'BRS Libra' and one genotype from self-rooted nursery trees were evaluated. The 22 genotypes were evaluated as fruit set and fruit yield in the growing seasons 2014/15, 2015/16, 2016/17 and 2017/18. Adaptability and stability were measured by the GGE biplot method. In the four years of evaluation, plants from self-rooted nursery trees had higher fruit set, yield as well as greater stability. On the other hand, the instability of plants grown on rootstocks from species other than the scion cultivar was greater. It can be concluded that under the tested conditions, the self-rooted genotype of 'BRS Libra' is a potential alternative for peach growers.

Objetivou-se com este trabalho avaliar a fenologia em função da temperatura do ar e a qualidade de frutos de acessos de Physalis spp. visando sua potencial utilização em programas de melhoramento genético. O experimento foi conduzido na Universidade Federal da Fronteira Sul - campus Chapecó, SC. O delineamento experimental foi inteiramente casualizado, com 67 acessos de Physalis spp. Foram avaliados componenetes fenológicos em três períodos diferentes, observando o (1) número de dias decorridos desde a emissão do botão floral à antese, (2) dias decorridos da antese à fixação de frutos e (3) número de dias para a emissão de nós. Com os dados de temperatura do ar, foi calculada a soma térmica (GD) necessária para alcançar o início de cada evento fenológico. No que tange às variáveis produtivas, foram analisadas a massa de fruto com cálice (g), massa de fruto sem cálice (g), sólidos solúveis (°Brix) e o volume médio de fruto (cm3). Os dados fenológicos foram submetidos a análises descritivas enquanto que os dados produtivos, à Análise de Componentes Principais (PCA – Principal Components Analysis). O primeiro período de observação (06 a 30 de janeiro) resultou em menor número de dias necessários para o aparecimento de nós e para atingir a frutificação à partir da floração. A presença do cálice nos frutos aumentou sensivelmente a massa média do fruto em aproximadamente 0,45 g. A temperatura influencia o ciclo fenológico dos 67 acessos de Physalis os quais, por sua vez, se diferenciam no que diz respeito à qualidade de frutos.

O arroz tem importância na alimentação da população mundial, sendo um dos cereais mais cultivados no mundo. O Brasil, atualmente, está entre os 10 principais produtores de arroz e este é considerado alimento básico na dieta dos brasileiros.  Objetivou-se avaliar a eficiência da inoculação de bactérias fixadoras de nitrogênio atmosférico na cultura do arroz em relação à adubação nitrogenada na região sul do Estado de Roraima. O experimento foi conduzido na região Sul do Estado de Roraima, no Município de Caracaraí, no Campus Novo Paraíso do IFRR, em delineamento em blocos ao acaso com quatro tratamentos e cinco repetições. Os tratamentos foram constituídos de quatro linhas com 5 m de comprimento e espaçadas em 0,5 m, totalizando uma área de 10 m². A área foi corrigida e adubada de acordo com a análise química do solo e recomendações para a cultura do arroz no Estado de Roraima. A inoculação foi realizada na semente antes do plantio, com densidade de 50 sementes por metro linear. Verificou aumento da produtividade de grãos e no número de perfilhos em função da dose de N aplicado. A inoculação com Azospirillum pode representar uma alternativa viável para substituir os adubos nitrogenados na cultura do arroz no Sul do Estado de Roraima.

No abstract

Ornamental plants require a substrate that ensures the germination and healthy growth and vigor of the seedlings. Thus, this study aimed at studying the most suitable substrate for the production of zinnia seedlings from waste wood.

There was increased fruit consumption with potential health benefits in the last years, being blackberry one of these fruits. The objective of this work was to evaluate the performance of Blackberry cultivars and the influence of main stem management on BRS-Tupy cultivar. The first experiment assessed the cultivars: BRS-Tupy, Cherokee, Xavante, and Guarani; in the second experiment the evaluated prunings were: drastic winter pruning, 2, 3, and 4 main primocanes. The variables analyzed were: green and dry leaf mass, leaf area, number and average fruit mass, production per plant, average size and percentage of fruit moisture, and soluble solids. In relation to average weight, fruit size and yield, BRS-Tupy cultivar was superior in both cycles evaluated. As for soluble solids the Cherokee cultivar was superior, but only in the 2016/17 cycle. In the second experiment, in terms of number of fruits and production, pruning of 4 primocanes in the 2016/17 cycle was superior, but in the next cycle the pruning of 3 primocanes equaled it in the production variable. The drastic pruning in these variables is shown to be lower in the two cycles evaluated. Concerning the variable size of fruit, a significant difference was found only in the 2017/18 cycle, where drastic pruning presented smaller fruits. Thus, it can be concluded that, in general, BRS-Tupy cultivar presents the best productive results and that pruning with 4 primocanes initially stands out alone.

Rootstock contributes to increase the absorption and nutrients translocation efficiency. We aimed to select rootstocks according to the nutritional physiological state of the scion cultivar. The experiment was carried out during three periods of leaf collect on the 4-year old peach cv. BRS Libra budded onto 21 rootstocks cultivated in a high density orchard. The following traits were evaluated: xylem water potential, dry leaf mass and chemical leaf nutritional analysis. The collected data were submitted to analysis of variance by the F test and some genetic parameters were estimated. When significant, the means were compared using the Scott-Knott test, at 5% significance. The principal component analysis was performed to verify the interrelationships between the rootstocks and the evaluated traits. The deviation from optimum percentage index was used to select the most nutritional stable rootstock. We observed that rootstock affects the dynamic absorption nutrient parameters in interactions with the scion. The highest foliar levels of P were found in the BRS Libra cultivar when budded onto the rootstocks ʹSanta Rosaʹ, ʹBarrierʹ, ʹTsukuba-1ʹ and ʹRosaflorʹ. The leaf analysis revealed a high variation in the mineral nutritional status among the studied Prunus rootstocks. Most of the mineral macro-elements varied between medium and optimal levels. The rootstocks ʹRigitanoʹ and ʹNemaredʹ showed less nutritional limitation and is recommended for cultivations in high density orchards.