Response of Tomato (Solanum lycopersicum L.) to Application of Potassium and Triacontanol

A number of phytonutrients isolated from fruits, vegetables, beans, grains etc., may have a role in protecting against cancer and cardiovascular diseases and also may delay the effects of ageing. Tomato (Solanum lycopersicum L.) is one of them cultivated widely as an important vegetable crop across the world. The fruit of tomato is a good source of vitamins, particularly ascorbic acid and antioxidants like beta-carotene and lycopene. Lycopene may protect against certain cancers such as prostrate cancer. As far as the growing of tomato is concerned, potassium as a fertilizer increases the lycopene content and other fruit quality characteristics of tomato, while triacontanol (TRIA) is also effective in increasing the yield and quality of tomato fruit. The present study was designed to increase growth, yield and quality of the crop, using both potassium and TRIA alone as well as in combination. The treatments included T-0 (K-0+deionized water), T-1 (K-0+TRIA 1 mu M), T-2 (K-30+TRIA 1 mu M), T-3 (K-60+TRIA 1 mu M), T-4 (K-90+TRIA 1 mu M) and T-5 (K-120+TRIA 1 mu M). Three-week old seedlings of tomato were transplanted to pots. The TRIA was sprayed on plants four times at 10 days intervals starting after 40 days of transplantation. Compared to control (T-0), all the treatments showed significant increases in the plant height, number of leaves, area per leaf, fresh and dry weights of plant, leaf-chlorophyll and carotenoids content, leaf-N, P and K contents, fruit yield, fruit-ascorbic acid and fruit-lycopene contents. The crop responded the best to the treatment combination K-90+TRIA 1 mu M that enhanced fruit yield, ascorbic acid, lycopene and beta-carotenoids content by 57.6, 6.7, 9.5 and 8.3%, respectively over the control. Thus, along with soil application of potassium (90 kg K/ha), very dilute foliar sprays of TRIA (1 mu M) could be used successfully for the amelioration of growth, yield and quality of tomato crop.