PERICARP STRUCTURE IN RELATION TO FRUIT CRACKING RESISTANCE IN LITCHI (LITCHI CHINENSIS SONN.)

Changes in mechanical properties and structure of the pericarp were comparatively studied in cracking resistant ‘Huaizhi’ and -susceptible ‘Nuomici’. The results indicated that the extension growth of the pericarp during aril expansion was only partly due to cell expansion but largely due to cell rearrangement from a vertical layout to a horizontal layout.
The cristate structure of the pericarp plus the spongy tissue in the mesocarp may have provided extensibility for the pericarp.
It is suggested that the formation of spongy tissue plays an important role in cell rearrangement and in buffering the stress from the expanding aril and therefore contributes to cracking resistance.
This was in accordance with the observation that the spongy tissue in the pericarp of crack-resistant ‘Huaizhi’ was larger than that of susceptible ‘Nuomici’. The tensile strength of pericarp is contributed to by endocarp and mesocarp cells beneath the cracks. However, there was no noticeable difference in endocarp in terms of cell size and cell layer between the two cultivars.

XXVI International Horticultural Congress: Citrus and Other Subtropical and Tropical Fruit Crops: Issues, Advances and Opportunities

X. Huang, H. Wang, J. Li, W. Yuan, H. Huang

cracking, pericarp structure, extensibility, strength

https://doi.org/10.17660/ActaHortic.2004.632.17