Production and quality of cucumber (Cucumis sativus L.) under greenhouse conditions using two pruning systems

In Mexico, vegetable production under greenhouse conditions has increased significantly in recent years; cucumber (Cucumis sativus L.) production is important, representing 10% of greenhouse crops. To evaluate the effect of pruning system on yield and quality of parthenocarpic cucumbers, a study was carried out in a greenhouse at the Agricultural Experimental Station of the Sonora University, during the period September 2009 to January 2010. The treatments were three cucumber hybrids (Caman, Esparon, and Modan), and two pruning systems (without removing the growing point of the main stem, and the growing point of the main stem removed and two lateral branches near the top of the plant allowed to grow, resulting in two branches growing downward). The experimental design was a completely randomized block design with factorial arrangement, with four replications. Days to flowering and to the beginning of harvest, commercial production (fruit number per plant, fruit weight and yield), as well as production quality (fruit length, diameter and firmness) were evaluated. During autumn-winter production, the agronomic management of cucumber in unheated greenhouses should be done without removing the growing point of the main stem, since the growth of new branches is delayed when the apical point of the main stem is removed and low temperatures retard the growth of secondary branches; this technique also requires less labor. Precocity was not observed in any of the hybrids, or due to pruning system; flowering began at 33 days after sowing and harvest at 69 days. The fruit number per plant in Esparon was greater with respect to Caman and Modan when the growing point of the main stem was not removed, with 17.7 fruit plant^-1; its implementation is recommended, since it also presented a low percentage of male flowers and fewer double fruit. Fruit weight and quality parameters were within the standards established for American type cucumbers, with an average weight of 330 g in Fancy category, 23.2 cm length, 5.0 cm diameter and 4.8 kg firmness.