Studies on the Content Change Characteristics of K, Ca and Mg in Pericarp of Litchi chinensis Sonn.cv. Feizixiao and Their Relation to the Pericarp's Coloring

The content change characteristics of K, Ca and Mg in the pericarp of Feizixiao litchi and their relation to pericarp's coloring were studied. The results showed that the content of the total K tended to drop. The content of the total Ca tended to rise. The content of the total Mg changed insignificantly. The contents of the total K, Ca and Mg significantly decreased in sequence. The content of the water-soluble K changed insignificantly during the earlier period, then it changed by the curve drop-rise-drop. The content of the water-soluble Ca dropped to the bottom on one week before harvest, and then it changed insignificantly. The content of the water-soluble Mg rose. Meantime, the contents of the water-soluble K, Mg and Ca significantly decreased in sequence. The higher content of total Ca was the key factor to improve the pericarp's reddening. The anthocyanin and chlorophyll contents were significantly relative to the univariate exponential regression equations of the contents of the water-soluble Mg and the total Ca, and the former was positive relative, and the latter was negative relative.