Fábio Vale Scarpare

Technical and economic assessment of trash recovery in the sugarcane bioenergy production system

Mechanized sugarcane (Saccharum spp.) harvest without burning has been increasingly adopted in Brazil, increasing trash availability on the field. This study aims at showing the importance of using an integrated framework tool to assess technical and economic impacts of integral harvesting and baling trash recovery strategies and different recovery rates as well as its implications in the sugarcane production, transport and processing stages. Trash recovery using baling system presents higher costs per unit of mass of recovered trash in comparison to system in which trash is harvested and transported with sugarcane stalks (integral harvesting system). However, the integrated agricultural and industrial assessment showed that recovering trash using baling system presents better economic results (higher internal rate of return and lower ethanol production cost) than the integral harvesting system for trash recovery rates higher than 30 %. Varying trash recovery fraction, stalks productivity and mean transport distance for both integral harvesting and baling systems, sensitivity analyses showed that higher trash recovery fractions associated with higher stalks yields and long transport distances favors baling system, mainly due to the reduction of bulk load density for integral harvesting system under those conditions.

Growing degree-days for the 'Niagara Rosada' grapevine pruned in different seasons.

Plant growth and development are proportional to biological time, or the thermal time of the species, which can be defined as the integral of the temperature over time between the lower and upper temperature developmental thresholds. The objective of this study was to investigate the efficiency of the growing degree-day (GDD) approach for vines of the ‘Niagara Rosada’ cultivar pruned in winter and summer seasons, and physiological phases (mobilisation and reserve accumulation) in a humid subtropical region. The experiment was carried out on 13-year-old plants in Piracicaba, São Paulo State-Brazil, evaluating 24 production cycles, 12 from the winter pruning, and 12 from the summer pruning. The statistical design was comprised of randomised blocks, using the pruning dates as treatment: 20 July, 4 August, 19 August, and 3 September (winter); 1 February, 15 February, 2 March, and 16 March (summer). Comparison of the mean values of GDD among pruning dates was evaluated by the Tukey test, and comparison between pruning seasons was made by the F test for orthogonal contrasts, both at the 5% probability level. The results showed good agreement between the values of GDD required to complete the cycle from the winter pruning until harvest when compared with other studies performed with the same cultivar grown in the Southern and Southeastern regions of Brazil. However, there was a consistent statistical difference between GDD computed for winter and summer pruning, which allowed us to conclude that this bio-meteorological index is not sufficient to distinguish vines pruned in different seasons and physiological phases applied in humid subtropical climates.

Fisiologia de mudas de morangueiro produzidas em sistema convencional e em vasos suspensos

A utilizacao de um sistema adequado para a conducao das plantas-matrizes fornecedoras de mudas e de fundamental importância, tanto com a finalidade de favorecer a quantidade de mudas produzidas, como para a qualidade das mesmas; por outro lado, a disponibilidade de mudas em periodos nao convencionais de plantio, atraves da utilizacao da frigoconservacao, possibilita a producao de frutos na entressafra, propiciando maiores ganhos pelos produtores devido aos melhores precos alcancados. Os presentes trabalhos tiveram como objetivos comparar o sistema de producao de mudas de morangueiro convencional com o de producao em vasos suspensos, assim como avaliar a frigoconservacao em mudas produzidas em sistema de vasos suspensos. Avaliaram-se a materia seca, os teores de carboidratos nas mudas e a percentagem de sobrevivencia das mesmas apos o transplante para local definitivo. No primeiro trabalho, foi utilizado o delineamento inteiramente ao acaso, em esquema fatorial 3x2 (tres cultivares: Campinas, Pelican e Guarani; e dois sistemas de producao de mudas), com tres repeticoes de 30 mudas; no segundo trabalho, utilizou-se o delineamento experimental inteiramente ao acaso, com cinco cultivares (Campinas, Dover, Pelican, Sequoia e Sweet Charlie) e nove repeticoes. Neste ultimo trabalho, apos a coleta, as mudas foram acondicionadas em sacos de polietileno e frigoconservadas durante 120 dias em câmara fria (-1 ± 1oC). As mudas produzidas em vasos suspensos apresentaram maior percentagem de sobrevivencia e maiores teores de carboidratos totais, com resultados semelhantes para as tres cultivares estudadas. A frigoconservacao de mudas de morangueiro produzidas em sistema de vasos suspensos resultou em baixa percentagem de sobrevivencia de mudas no experimento.

Determinação de índices biometeorológicos da videira 'Niagara Rosada' (Vitis labrusca L.) poda, em diferentes épocas

ABSTRACT - The aim of this study was to determine four biometeorological indexes approach: Primault (P), Heliothermic Huglin Index (HHI), Heliothermic Geslin Index (HGI) and Photothermal Units (PU) for ‘Niagara Rosada’ cultivar pruned in the winter and summer seasons. The experiment was carried out on 13-year-old plants in Piracicaba, state of Sao Paulo-Brazil, evaluating 24 production cycles, 12 from the winter pruning and 12 from the summer pruning. The statistical design was comprised of randomized blocks, using the pruning dates as treatment: July 20th, August 4th, August 19th, and September 3rd (winter); February 1st, February15th, March 2nd, and March 16th (summer). Comparison of the mean values of P, HHI, HGI and PU among pruning dates was evaluated by the Tukey test, and comparison between pruning seasons was made by the F test for orthogonal contrasts, both at the 5% probability level. The results show that the inclusion of the meteorological element insolation and the photoperiod factor on thermal sum requirement is not proved effective in determining an average value for cycle prediction in vines pruned in different seasons; none of the biometeorological indexes are efficient for harvest prediction in vines pruned in different seasons; independent of the time when the cycle starts, the average of 120 days can be used to estimate the harvest date of vines in climate region Cwa.