Effect of crop load on fruit nutritional and nutraceutical traits of greenhouse tomato

Abstract

ABSTRACT This study aimed to evaluate the effect of crop load on the fruit quality traits especially nutritional and nutraceutical properties of two cultivars of greenhouse tomato (Solanum lycopersicum L.) i.e. ‘Grandella’ and ‘Isabella’. The crop load treatments were: saving one fruit per truss (1F), two fruits per truss (2F), three fruits per truss (3F), and no fruit thinning (control). The results showed that decreasing crop load increased the dry matter content, glucose, fructose, and sucrose concentrations of fruits because of less competition between fruits of each truss and higher relative expression level of tomato hexose transporter genes (LeHTs). Higher transport of sugars toward fruits of 1F resulted in high secondary metabolites concentration. The high secondary metabolites concentration with high fruit load in control that has low soluble sugar availability may result from the opportunity to take advantage of the excess pool of carbon to build cost-free carbon-based secondary metabolites. A reduced crop load would be a recommended management strategy to improve greenhouse tomato quality.