The 2012 ASHS Annual Conference

In Mexico greenhouse cucumber in low-tech greenhouses is an alternative for small producers whom do not need large investments for crop management. However, temperature and relative humidity must be maintained from 22 °C to 25 °C and 80% to 85%, respectively. Controlling these parameters is the main problem regarding the internal climate of low tech greenhouses. This problem is reflected in the homogeneity of the quality and yield of the cucumber fruits, especially in months with low temperatures. The objective of this work was to evaluate the effect of harvest dates on the homogeneity of quality, and the yield of cucumbers grown in a low-tech greenhouse during the autumn–winter 2010 cycle. Plants of cucumber (Cucumis sativus L) cv. paraiso, were grown in a low-tech greenhouse at the Universidad Politecnica de Guanajuato. The internal relative humidity and temperature were recorded weekly during the cycle of production using thermohigrometers. Cucumber fruits were harvested in 5 different dates from November 2010 to January 2011. The monthly average temperature and relative humidity were lower than the recommended in a range from 2 °C to 5 °C and up to 20%, respectively. The uniformity of fruit quality was assessed by the following parameters: appearance, weight, length, diameter, color, °Brix, and titratable acidity. The aspect of fruit was acceptable, with no defects caused by pests, stress or mechanical damage. No significative effects were detected from harvest dates on the quality parameters studied, which ensure the crop homogeneity during all production cycle. Yield was 3.5 kg·m^-2, which is within the range recommended for this crop in Mexico although it is low when compared to 6 kg·m^-2 recommended worldwide. It was concluded that despite the constraints about controlling the temperature and relative humidity during the management of the greenhouse cucumber in low-tech greenhouses, it is possible to obtain products with quality and yields comparable to those from the fruits obtained in high-tech greenhouses. This provides a crop alternative for small producers, as no high investment or operation costs for the greenhouse cucumber production are required.