DESIRABLE TRAITS FOR CUCUMBER PLANTS GROWN UNDER GREENHOUSE AND HYDROPONICS AT HIGH PLANT DENSITIES

Abstract

The contribution of several morphologic characters of the cucumber plant (Cucumis sativus L.) to the yields per plant and per surface unit, feasible to incorporate in a suitable ideotype to be managed in a production system subjected to early trimming of the stem apex (plants 1 m high) and grown at high population density in low restrictive environments (greenhouse and hydroponics), was evaluated in this study. Two experiments were established; Experiment I included 11 varieties planted in two population densi-ties (9 and 16 plants m^-2); Experiment II involved four varieties which represented two groups of contrasting characteristics. In both experiments a randomized block design was used with split plot arrangement of treatments, with plant densities as main plots and varieties as sub-plots. The varieties ‘Monarch’ and ‘Sprint 440’ combined the greatest number of desirable traits for a cucumber ideotype adapted to this system, such as: thick stem (7 and 6.7 mm), more leaf area (43.5 and 39.7 dm²) and more fruits per plant (7.4 and 7.3), in contrast with varieties ‘Moctezuma’ and ‘Indy’. The varieties with higher leaf area produced two more fruits per plant than those of smaller area, and this trait was the one more correla-ted with yield. No differences in yield per surface unit were found as the plant density increased from 9 to 16 plants m^-2, so the lowest density is recommended for this production system.