Dr Banarsi Lal Salad crops are now gaining popularity because of their nutritional value in the diet. Lettuce (Lactuca sativa L.) is one of the most popular salad crops grown commercially across the globe. It was firstly cultivated in Egypt. Its demand is increasing day-by-day due to its nutritional and diet values. Lettuce crop has ample scope in present era and farmers can improve their livelihood security by its commercial cultivation. Better quality of lettuce can help to find more marketing channels and thus the farmers can fetch more money by growing this crop. It can also be grown in green house, poly house or hydroponically. Earlier, Europe and North America were the leading producers of lettuce but now lettuce’s production and consumption had spread across the world. Presently China is the leading producer of lettuce in the world, followed by the USA. India ranks 3rd in the production of lettuce occupying 4 per cent of the world’s total production. The Nilgiri mountain of South India is emerging as the hub of lettuce production. The demand for lettuce is growing rapidly. The restaurant industry is booming steadily because the country’s young generation preferring international cuisine like a burger, pizza, sandwiches etc., where lettuce is an integral part. Lettuce is classified into four major types, namely (a) Head lettuce (Lactuca sativa var. capitata), (b)Leafy lettuce (Lactuca sativa var. crispa),(c) Cos or Romanian lettuce (Lactuca sativa var. longifolia) and (d) stem lettuce (Lactuca sativa var. aspergina). Among the cultivated varieties, Iceberg and Great Lakes are the popular head type lettuce grown in India. The head of iceberg lettuce is light green, round in shape and tightly packed with lettuce leaves like cabbage head. Lettuce is an excellent source of vitamins, minerals and antioxidants. It lowers the cholesterol levels and protects neuronal cells of the body. Iceberg lettuce has high water content (95 percent) and low in calories (13 kcal/100g), which is very effective for weight loss in human beings. Iceberg lettuce helps to fight against heart diseases and strokes and protecting infants from neural tube defects during pregnancy. Regular inclusion of lettuce in salads is known to prevent osteoporosis, iron-deficiency anemia, cardiovascular diseases, age-related macular disease in the elderly people, cancers and Alzheimer’s disease. Lettuce has low calorie content and zero fat. It is a good source of chlorophyll and Vitamins A, B1, B2, C and K, folic acid and manganese. It reduces anxiety and prevents cancer cell growth. Lettuce is moderately salt tolerant. It can be grown in the wide variety of soils. Generally well-drained fertile soil with a pH of about 6.0 is most suitable for the growth of lettuce. It is a cool-season crop requiring a mean air temperature of 10 – 20°C. Cool nights are essential for good-quality lettuce. It is grown mainly in areas having cool summers and mild winters. Lettuce cultivation can be done without soil with the help of hydroponic technique or protective cultivation. Its leaves are mainly green and red colour spectrum. Its plants can spread in about 15 to 30 cm. Lettuce generally passes through six distinct development stages namely seed, cotyledon, seedling, rosette, cupping and heading periods. The seed stage occurs from pre-planting to emergence. Once exposed to water and appropriate temperature, the seed germination begins, usually requiring as little as 12 hours for fall planted varieties or up to 7 days for winter planted varieties. Once the plant sheds the seed coat and emerges from the soil, it enters into the cotyledon stage. The cotyledon stage last until the plant is able to establish its roots. Once the root has grown a couple of inches, the seedling begins to grow upwards and the first true leaf emerges. From emergence from the soil to the first true leaf generally requires about 7 days for fall planted lettuce and 20 days for winter planted lettuce. The seedling stage occurs from the first true leaf until the plant develops a distinct circular cluster of leaves known as a rosette. The rosette stage for fall planted lettuce generally lasts for 25 days, but may last as long as 50 days for winter planted lettuce. Cupping begins when the tips of the inner leaves begin to curl inwards on the edges. Cupping signifies that the beginning of head formation is near, and will usually last about 7 days for fall planted lettuce and 14 days for winter planted varieties. Heading begins once the cupped leaves begin to overlap and cover the growing point of the plant. Head formation will continue until the crop is ready for harvest, which generally last about 30 days for fall planted varieties and about 45 days for winter planted varieties. Fall planted lettuce may require as little as 65 days from the beginning of germination to harvest. Lettuce seeds are very thin and delicate. About 325 grams seed is required for one-hectare lettuce cultivation. There are about 800 seeds of lettuce in one gm. Planting date is primarily a function of the variety and desired harvest date. Planting begins as early as late August and continues into the middle of December. There is need to prepare raised bed nursery with a well rotten Farm Yard Manure or compost mix with soil at the rate 4 kg/m2.Make a nursery bed 100 cm wide and 30 cm in height. Fertilizers can also be mixed in the soil while preparing the nursery. Lettuce’s seeds should be sown in lines at a spacing of 5 cm between rows and 1.5-2 cm depth. Optimum germination and growing temperatures vary depending upon the variety planted. The seed should be covered with soil and Farm Yard Manure (FYM) mixture. Plants are ready for transplanting in about 4 weeks. Proper management of diseases and pests is also necessary for a healthy crop. Seedlings should be hardened before transplanting. Seedlings are transplanted in flatbeds at a spacing of 45 × 45 cm or 45 × 30 cm. About 66665 seedlings are required to cultivate in the one-hectare area. The application of fertilizers influences the growth and yield of lettuce. For growing lettuce, 150-200 q/ ha of farmyard manure add 25 kg of both Nitrogen and Potash and 90 kg/ha of Phosphorus can be applied. In sandy and sandy loam soils without manure, 40-50 kg of Nitrogen and 75-100 kg of phosphorus and potassium per hectare should be applied. However, fertilization would depend upon the soil fertility status and nutrient availability. About one third to one half of the nitrogen can be applied when seedings are transplanted and the rest after thinning operation. Irrigation is essential in lettuce farming. Frequent and light irrigations are very effective in increasing its production. After planting, crops should be irrigated at 8 to 10-day intervals. About 30 per cent production can be increased by drip irrigation system. Roots of lettuce crops are shallow, so weeding should be done carefully without disturbing lettuce. Harvesting of lettuce is done as soon as the plants reach at the acceptable size and firmness. Harvesting is done before the leaves become hard and before the seed stalks start to bold. Lettuce is generally cut with a long-handled sharp knife. The maturity of the crop depends on the variety of lettuce and the purpose for which it is grown. In Head, lettuce for the market is allowed to grow to full size and develop a solid head, but it is often harvested before the head is well-formed for home use. Leaf lettuce plants may be thinned at various times, removing the largest leaves for use and leaving smaller ones to develop. Lettuce has short shelf life so it should be marketed as fresh one. It should be transported in the nearby market as soon as possible after harvest. Lettuce should be packed carefully into a thick cardboard box. Reasi district of J&K has immense potential in lettuce production. Krishen Singh of Jagore village in Reasi district of J&K is growing organic lettuce commercially and his lush green field has become centre of attraction for other farmers of the area. (The author is Scientist & Head of KVK, Reasi (SKUAST-J).
