Chemical fertilizers as a component of INM in Tomato

Introduction  Chemical fertilizer are mined, refined or manufactured product containing one or more essential plant nutrients in available or potentially available form  They are less bulky, easy to transport and quickly available to plants  They are available either in granular, powder or liquid formulation  Kinds of fertilizers used for tomato are nitrogenous, phosphatic and potassic. Besides the straight fertilizers having only one chemical compound, there are mixed fertilizers containing two or more chemical compounds in suitable proportions

Recommended dose of chemical fertilizers for tomato  Nitrogen: kg/ha from urea or ammonium sulphate  Phosphorus: kg/ha from Single superphosphate  Potassium kg/ha from Muriate of Potash

Time of application of fertilizers One third nitrogen and full phosphorus and potash should be applied in soil before transplanting The remaining amount of nitrogen should be broadcast as top dressing in two equal split doses after 30 and 60 days of transplanting Urea can be applied in more than two split doses (3-4) after every weeding to reduce the loss due to leaching Nitrogenous fertilizers should be top dressed around the plants. Light irrigation necessary after broadcasting or fertilizer should be applied soon after irrigation when there is sufficient moisture

Contd….. Method of application of fertilizers Broadcast  Fertilizers are applied by hand or tractor at the time of soil preparation  Broadcasting of fertilizer should be done just before planting to avoid loss of nitrogen due to leaching Source: / Agriculture%20Pages/AgriMechanization1.aspx/

Contd….. Banding  Practiced when the quantity of fertilizer to be applied is less  Fertilizer applied to the side of the seed row (2 inches away and 2 inches deep)  Application too close to the seedling may be injurious to the roots. Necessary to irrigate the field soon after the application of fertilizers. Source: 9e07.htm

Contd….. Foliar Spray  Foliar spray of urea beneficial when plant growth is slow  Urea (2-3%) is sprayed depending on the age of the plant  Boron and Calcium are also applied as foliar spray Source: Plant

Contd….. Fertigation  Soluble fertilizers are mixed along with water through drip pipes.  Method followed in the field as well as in greenhouses  Fertigation in greenhouse is completely computerized for quantity of nutrients to be applied and time of application. Source: c1.htmhttp:// c1.htm

The choice of fertilizer depends on soil type, soil pH, organic matter, climate, water/irrigation facilities, crop condition and stage of plant growth, cost and economics of fertilizer application, market price of vegetable etc. The quantities of the three basic plant nutrients (N, P and K) required to be applied to the soil can be determined by the soil test The soil test laboratories provide the information on soil status and also give recommendations on the type of crops suitable for growing on that soil. Let us sum up