Correlation between bloom formation on fruit surface of grafted cucumber and rootstocks and absorption and distribution of silicon

The bloom on fruit surface of cucumber impacts its commercial quality, and the bloom formation dependens on silicon absorption of plants to some extent. Four inbred line rootstocks with bloom on fruits (Z1-Z4) and four without bloom (Z5-Z8) were selected to graft cucumber cv. Jinyou NO.1 respectively, the correlation between bloom formation on fruit surface of grafted and ownroot cucumbers and absorption and distribution of silicon was investigated, using ownroot cucumber as control. The results showed that: Fruits of grafted cucumber on blooming rootstocks Z1 and Z2 were bright and smooth, almost no bloom on the surface, while those on bloomless rootstocks Z5, Z6, Z7 and Z8 had heavy bloom, dark grey in colur, the same was true for those grafted on blooming rootstocks Z3 and Z4. The silicon content in organs of cucumber plants without fruit bloom was significantly lower than that with bloom, more silicon was found in pericarp than in sarcocarp. There was no definite relationship between bloom formation on fruit surface of grafted cucumber and rootstocks themselves, the silicon absorption of cucumber was significantly reduced when grafted on bloom-removing rootstocks.