Growth and yield performance of lettuce (Lactuca sativa Linn) under protected and conventional cultivation

Protected cultivation is not widely used in the Philippines, despite its known benefits, because of lack of uptake by farmers who have not seen the benefits demonstrated in their region. Furthermore, lettuce can be a difficult crop to grow in the Philippines, where heavy rains can damage the delicate leafy crop. This study aimed to evaluate the performance of different lettuce varieties when grown under protected structures that prevent rain entry. The study was laid out in split-plot arranged in Randomized Complete Block Design (RCBD) with cultivation system (protected cropping & open field) as the main plot while the lettuce variety (leafy-type & head-type) as the sub-plot, replicated three times. The protective structure enhanced crown size, increased yield and produced healthier plants with reduced incidence of disease. Leafy-type obtained the largest crown size and head-type was less affected by disease in the first cropping. The study suggested that protective structures can be an asset in the enhancement and sustainability of lettuce production in preventing further damage on crops due to excessive rainfall and wind but would not be profitable when use during warmer months.