Relating Leaf Nutrient Status to Fruit Quality Attributes in Litchi cv. ‘Mauritius’

ABSTRACT

Litchi (Litchi chinensis Sonn.) ‘Mauritius’ is a popular export cultivar due to its attractive red color and excellent fruit quality. Three orchards were selected based on planting distance and routine pruning practices followed by each growing season. Orchards A and B are essentially similar regarding these production practices, whereas orchard C had overlapping canopies due to lack of routine pruning practices after each growing season and short planting distance. Canonical variate analysis was used as a statistical tool to compare fruit quality attributes from different orchards (A, B, and C) in terms of physical, chemical and sensory parameters and correlating to leaf nutrient status. The correlations and plot of loadings of the variates indicated that skin color (visual), color values (chroma and hue angle, h°), fruit weight, firmness, and consumer acceptability were the main factors that discriminated orchard C from the other two orchards. The soluble solids concentrations, titratable acidity and fruit taste were the quality attributes discriminating orchard A from orchard B. The relationship between the leaf nutrients and fruit quality attributes showed positive relationships between leaf potassium (K) and anthocyanin content and titratable acidity (TA); leaf phosphorus (P) and pericarp h°, leaf nitrogen (N) and fruit weight; leaf calcium (Ca) and fruit firmness.

Keywords:

• Litchi chinensis Sonn.
• fruit quality modeling

ACKNOWLEDGMENTS

This work was partly supported by a grant from the South African Litchi Growers' Association and Technology and Human Resources for Industry Program (THRIP), a partnership program funded by the Department of Trade and Industry and managed by the National Research Foundation (NRF). Editorial support was given by Ms Karin Zeeman (University of Pretoria) and statistical analysis was done by Ms Marie Smith (Agriculture Research Council, Silverton, Pretoria).