. RESPONSE OF TWO CUCUMBER HYBRIDS TO GROWING SEASON AND UNHEATED PLASTIC HOUSES TYPE UNDER NORTH DELTA CONDITIONS

Abstract

The experiments were carried out in the years of 2000, 200 I and 2003 at Sakha Protected cultivation Site, Ministry of Agric., Kafr EJ-Sheikh Governorate. The main objective oftbis research was to study the influence of growing seasons (winter and early summer) and types (size) of unheated plastic house (the singlespan and the doublespan having round arch) on growth, yield and quality of two cucumber F1 hybrids (Primo and Petostar) and microclimate of the plastic houses. The experimental design used was the split-split-plot with four replications. The two growing seasons were assigned in the main plots, the two plastic house types were alloted in the sub-sub-plots. The area of sub-sub­ plot was 48 m2 (144 plants). Dimensions of the singlespan house were 8.5 m width, and 55 m length and 3.2 m height which covered an area of 467.5 m 2 . The dimensions of the doublespan house were 17m width, 55 m length and 5.1 m height which covered an area of935 m2 • The framework of plastic houses was galvanized pipes and covered with a UV stabilized PE with thickness of 200 microns. Data were tested by analysis of variance and Duncan's multiple range test was used for comparisons among the means of treatments.

Results are summarized as follows: 5.1. Microclimate of unheated plastic houses: 5.1.1. Air temperature: The doublespan and the singlespan plastic houses had higher minimum, maximum and average air temperatures than those of the open field (control). The doublespan plastic house had the highest minimum and average air temperatures and air temperature at 18 o'clock, while the singlespan plastic house had the highest maximum air temperature during the winter and the early summer seasons.