Nutrient requirements of solanaceous vegetable crops

Nutrient requirements of solanaceous vegetable crops

Shanhua, Tainan AVRDC Taiwan

1997

p.58-70

S631.3.M6

Solanaceous vegetables (tomato, eggplant, hot and bell peppers) require large quantities of nutrients to yield well. The quantities taken up by them depend on the yields of fruit and vegetative parts, which in turn are influenced by a number of genetic and environmental variables. To produce a ton of fresh fruit, the crops need to absorb, on average, 2.5 to 3 kg N, 0.2 to 0.3 kg P, and 3 to 3.5 kg K in tomato; 3 to 3.5 kg N, 0.2 to 0.3 kg P, and 2.5 to 3 kg K in eggplant; and 3 to 3.5 kg N, 0.8 to 1 kg P, and 5 to 6 kg K in hot and bell peppers. In the absence of production constraints, nutrient uptake and yield are very closely related. Fruits and fruiting parts in this group of vegetables contain 45 to 60% of the total N, 50 to 60% of the total P and 55 to 70% of the total K absorbed by the plants. The major proportion of the nutrients in fruits are absorbed after flowering occurs. Furthermore, the proportion found in fruit declines with the increase in their application. The period of greatest nutrient requirement for N, P, and K is from about 10 days after flowering to just before fruits begin to ripen. A small proportion of N and still smaller proportions of the P and K in fruits are translocated from vegetative parts. Diurnal variation in nutrient absorption occurs, with the proportion of nutrients absorbed during night greater for P than for N and K. Tomato and peppers use only a small proportion of the N available from inorganic sources. Eggplant, however, is very effective in making use of plant nutrients already available in the soil. All species prefer NO3-N. High concentrations of NH4-N in the growing medium greatly reduce growth and productivity, especially in tomato and capsicums. The quality of nutrients to be applied depends on the yield status, and the growing conditions. Because vegetative and reproductive stages overlap in these crops, and because the plants need nutrients even up to fruit ripening, fertigation, split application of fertilizers, slow release N fertilizers, and integrated use of inorganic and organic nutrient sources promote nutrient use efficiency and crop productivity. These practices also reduce nutrient losses, thus making them environmentally friendly.[AS]

Managing soil fertility for intensive vegetable production systems in Asia; Proceedings of an

Research > Published Articles