Growth and Physiological Characteristics of Some Local Varieties of Cucumber (Cucumis Sativus L.) under Drought at Seedling Stage
Abstract
This research was carried out to evaluate drought tolerance of 32 varieties of native cucumber in Vietnam. The seedlings were grown in pots containing 5 kg of mixture (soil + coconut fiber, ratio 1: 2) with basal fertilizer of CaO: N: P2O5: K2O with: 10g: 2g: 2g: 1.5g, respectively, per pot. All pots were placed in a nethouse. The moisture of the pots were maintained at 80-85% of saturation at all time except at stress stage. In stress-treatment, watering of 2- expanded-leaf seedlings were withheld 10 days, then watered again. The results showed that, drought reduced leaf number, leaf area, plant height, and shoot diameter in most non-tolerant varieties ( low DRI). The drought-tolerant varieties (DRI > 1), had a slight reduction of leaf number but had a strong reduction of leaf area, that might help reduce evaporation. In these varieties, however, there was only a slight reduction of shoot diameter that might not limit water-transportation. The result also showed that 13 varieties had good drought tolerance, which could be used as the materials for breeding of drought resistance.