Abstract

This study was conducted to determine and compare the inhibitory effects of chromium on seed germination and early seedling growth of melon (Cucumis meloL.). Chromium applications were controls; 2.5, 5, 10, 25, 50, 75, 100, 200 and 300 mgl^-1 Cr in germination stage, and controls; 2.5, 5, 10, 20, 30, 40, 50, 60 and 70 mgl^-1 Cr in early seedling stage. Excess chromium was limited to germination rate, germination index, mean germination time and germination uniformity index values in germination level. Radicle length, radicle fresh and dry weight, hypocotyll length, hypocotyll fresh and dry weight, growth tolerance index and seedling relative growth rate was negatively affected by the increased chromium concentrations at the seedling stage. Response of seedlings to chromium was more than that of seed germination. This event is based on the impermeability of seed coats and selectivity of embryos against chromium.

Key words: Chromium, germination, seedling, tolerance index, relative growth rates.

Abbreviation

GUI, Germination uniformity indexes; RL, radicle length; HL, hypocotyl length; RFW, radicle fresh weight; HFW, hypocotyl fresh weight; RDW, dry weights of radicle; HDW, dry weights of hypocotyls; GTI, growth tolerance index;  RGR, relative growth rates.