Vertical conduction system and plant density of mini watermelon in greenhouse

The consumption of differentiated products increased during the last years. This niche of market is of great interest by growers to achieve higher returns compared to traditional products. One example is the mini watermelon, which is grown not only under field, but also under greenhouse conditions. Plants under greenhouse must be conducted vertically and pruned. This research aimed to investigate the influence of three conducing systems (S1= one stem and one fruit per plant attached to the main stem; S2= one stem and one fruit per plant attached to the secondary stem, and S3= two stems per plant and one fruit attached to the main stem) and two plant densities (2.4 and 4.8 plants/m(2)) on the vegetative, productive and qualitative characteristics of mini watermelon grown in the vertical system. The plant conduction system with two stems and one fruit increased yield of fruit, without differing from S1. For this system, the increased density of 4.8 plants/m(2) increased yield by approximately twice the density of 2.4 plants/m(2), but it caused 12.5% of reduction on average fruit weight. Regardless of plant density and conduction system, fruits presented adequate quality for marketing and yield corresponding to 2 to 4 times the national average for watermelon grown in the traditional system.