Effects of bagging on the content of Ca, Mg, K in pear.

In order to investigate the effect of bagging on mineral contents in pear, young fruits of three pear cultivars, Huangguan, Zaokui and Xizilu, were covered by double layer paper bag (outer grey-colored layer and inner dark-colored layer) at the early development stage. The results show that bagging has no significant influence on weight per fruit. No marked difference was found of the contents of Ca, Mg and K in the peel and flesh between bagging fruits and control (non-bagging) ones, expect Huangguan pear in 2006 where bagging reduces obviously Ca content, Ca/K and Ca/Mg ratios in the peel, and Xizilu pear in 2006 and 2007 where Mg content in peel and flesh was reduced by bagging. This indicates that the bagging affects the uptake of Ca, Mg, with greater effect on the contents of Ca and Mg in peel than in flesh, and for Huangguanpear, bagging, reduces mainly Ca content, Ca/K and Ca/Mg ratios, but with no significant effect on K content.