Fenologia reprodutiva da pitaya vermelha em Jaboticabal, SP

The dragon fruit (Hylocereus undatus) is recent crop cultivation in Brazil and there is still lack of studies to support the farmers. So, this research aimed to characterize the reproductive phenology of the crop in the region of Jaboticabal, Sao Paulo State, Brazil. It was evaluated red dragon fruit clones over two environmental conditions - under plastic screen black and white, with 50% of shady level, from March 2009 to December 2010. It was observed that the issuance of floral buds and the flowering on dragon fruit culture occurs with a combination of high temperatures and rainfall, with constant emission of floral buds from November to March while the flowering on dragon fruit culture occurs until mid-April. The color of plastic screen had influenced on amount of flowers. The time elapsed since the issuance of flower buds to anthesis is from 18 to 23 days, while the harvest occurs from 34 to 43 days after flower opening. At Jaboticabal, the time of appearance of flower bud to fruit harvest is from 52 to 66 days.

Características pós-colheita em frutos de pitaya orgânica submetida a diferentes doses de irradiação

The objective was to evaluate the influence of different irradiation doses in post-harvest characteristics of pitaya organic species Hylocereus undatus grown in the municipality of Itajobi - SP. The experiment was conducted at the Fruit and Vegetable Department of Agribusiness Management and Technology - FCA / UNESP - Botucatu - SP from December 2008 to January 2009. The radiation process was conducted at the Institute for Energy and Nuclear Research (IPEN) located in Sao Paulo. The design was randomized blocks with six treatments and three replications. The fruits were harvested on the third day after onset of color, selected, cleaned, packed in polystyrene trays covered with PVC film, pre - cooled (8 ° C for 24 hours) and subjected to different doses of gamma irradiation (0.0; 0.2, 0.4, 0.6, 0.8 and 1.0 kGy of cobalt-60) and subsequently stored in cold temperature of 8 degrees C, with relative humidity of about 85 ± 5%. The fruits were evaluated at twenty days after irradiation for pH, soluble solids (SS), Titratable Acidity (TA), ratio (SS / TA) and percentage loss of mass (weight). Data were subjected to analysis of variance and means compared by Tukey test at 5% probability. There were no statistically significant differences (p <0.05) for pH (4.82), soluble solids (11.33) Titratable acidity (0.12) and ratio (79.42) compared to non-irradiated fruit. Regarding the percentage of loss of mass (weight), the highest among the patients treated irradiated with 0.8 kGy (12.12%), whereas for treatment at a dose of 0.0 kGy (irradiated) showed a lower loss weight (11.59%), a result that differs significantly (P <0.05) from the remaining doses of irradiation. The loss of mass (weight) of fruit irradiated with other doses was not statistically significant (P> 0.05).