Effect of fertilizers on Lettuce (Lactuca sativa) yield, physical and organoleptic properties

Abstract

The current study was carried out in an attempt to correlate the yield attributes with the physical properties of lettuce. The effect of four types of slow release and soluble fertilizers and a control treatment (only water) on the growth and yield attributes (such as number of leaves, head size, fresh and dry weight of head) of two Lactuca sativa cultivars (Great Lake and Nabucco), was investigated at two different sowing dates in Spring. Yield differences in general were not significant between fertilizer treatments and control. The physico-chemical [moisture content, color parameters (L*, a* and b*), firmness, nitrate content, total phenols] and sensory parameters of these two cultivars were studied. A trained panel of ten individuals and an untrained panel of 60 individuals were employed for assessing the sensory properties and consumer preference of lettuce, respectively. Principal Component Analysis was employed in order to correlate the physico-chemical parameters with the sensory properties as well as with field yield productivity at the various fertilizer regimes employed. Significant differences were only found between the two cultivars whereas in most cases no significant differences were observed among fertilizer treatments of the same cultivar.