Lettuce (Lactuca sativa L.) is one of the most important salad crops worldwide. In Taiwan, lettuce is primarily eaten as a cooked vegetable and has become increasingly popular. Concerning cultivation, lettuce is much less damaged by pests compared with other leafy vegetables; thus, the production has been increasing in recent years. To achieve high yield and good quality, lettuce is also grown in high tunnels, especially for organic production. Batavia lettuce and looseleaf lettuce are the main types grown. Landrace ‘Fu San’, which is adapted to high temperature, high humidity, and varied climate, is the only Batavia lettuce currently being grown in Taiwan. Other foreign commercial cultivars cannot compete with or substitute for ‘Fu San’. However, ‘Fu San’ has two disadvantages: small plant size and slow growth rate. Developing a cultivar superior to ‘Fu San’ would be beneficial to lettuce production not only in Taiwan, but also in other subtropical areas.
Single-seed descent (SSD) is a method of plant breeding that has the advantage of obtaining homozygous lines in a much shorter time than conventional plant breeding methods by growing out multiple generations in the same year. The SSD method can be applied to self-fertilized species with high genetic variances for economic characters or crops for which self-fertilization is obligatory for commercial use (Brini, 1966; Fehr, 1987; Macchiavelli and Beaver, 2001). ‘Taoyuan No. 1’ was developed by the SSD method to promote vegetable production in high tunnels. This newly released cultivar with good quality and high yield is described.
AOAC2003aTotal dietary fiber in foods enzymatic–gravimetric method. In: Horwitz W. (ed.). Official methods of analysis of AOAC International. 17th Ed. Gaithersburg MD
AOAC2003bVitamin C (total) in food semiautomated fluorometric method. In: Horwitz W. (ed.). Official methods of analysis of AOAC International. 17th Ed. Gaithersburg MD
FehrW.R.1987Principles of cultivar development: Theory and technique. Macmillan New York NY
LiuX.ArdoS.BunningM.ParryJ.ZhouK.StushnoffC.StonikerF.YuL.KendallP.2007Total phenolic content and DPPH radical scavenging activity of lettuce (Lactuca sativa L.) grown in ColoradoLWT-Food Sci. Technolo.40552557
MacchiavelliR.BeaverJ.S.2001Effect of number of seed bulked and population size on genetic variability when using the multiple-seed procedure of SSDCrop Sci.4115131516
NicolleC.CarnatA.FraisseD.LamaisonJ.L.RockE.MichelH.AmourouxP.RemesyC.2004Characterisation and variation of antioxidant micronutrients in lettuce (Lactuca sativa folium)J. Sci. Food Agr.8420612069