Effect of organo-mineral fertilizer rates on nutrient uptake and fruit quality of snake tomato (Trichosanthes cucumerina L.)

Abstract

The snake tomato (Trichosanthes cucumerina L.) is a member of the botanical family Cucurbitaceae. The crop regarded as a substitute to the regular tomato (Lycopersicon esculentum (L.) Mill.) has not been well researched and there is a need to develop agronomic practices suitable for its cultivation. It was therefore the objective of this work to evaluate the performances of the crop when applied with different fertilizer types/rates and to determine the optimum fertilizer requirement. Field experiments were therefore conducted in Abeokuta in 2007 and 2008 to determine the growth, fruit quality/yield and plant nutrient uptake in responses to fertilizer types/rates. The treatments included two cropping seasons and organo-mineral fertilizer (OMF) rates applied at 5, 10, 20 and 40 t ha-1 where both zero application and NPK 15:15:15 served as the control. The experiment was arranged in a randomized complete block design with three replicates. The result indicated that 40 t ha-1 OMF rates was significant higher in P, K, Ca and Mg, but lower in Zn and recorded higher dry weight but was not different from 20 t ha-1 OMF in fresh weight plant biomass and in yield components. The NPK treatment was however lower compared to plants treated with 10, 20 and 40 t ha-1 OMF in total, vine, leaf and root fresh weight but not different from 10 t ha-1 OMF in root fresh weight. Despite that sugar was higher in 10 t ha-1 OMF, the zero application was higher in ascorbic acid and starch compared to lower or higher OMF rates. The increased inorganic content at higher OMF rates and probably the higher micro-nutrient contents could have resulted in reduced fruit quality with the lower ascorbic acid level.