EFFECT OF AMMUNIUM TO NITRATE RATIO ON SOME CHMECIAL PARAMETER AND CALICIUM OXALATE CRYSTALS FORMATION IN LEAVES OF SPINACH (Spinacea oleracea L.) LOCAL CULTIVAR.

Abstract

Abstract : A field experiment was carried out at Al- Kufa in Najaf Governorate /Iraq during winter growing seasons 2009-2010 and 2010-2011 to the study the effects of N-NH4+/N-NO3- ratios of 0:0 , 1:0 , 0:1, 0.50:0.50 , 0.75:0.25 and 0.25:0.75 (NH4+: NO3-) with total nitrogen 400 mg.L-1 on the chemical parameters and calcium oxalate crystals formation of spinach (Spinacea oleracea L.) local cultivar. A Randomized Complete Block Design (R.C.B.D.) was used with three replications and Duncans multiples range test was used to compare means at 0.05 level.The results showed that the ratio 0:1 (NH4+:NO3-) increased calcium, oxalic acid and oxalic acid / calcium ratio , the ratio 1:0 markedly increased ascorbic acid and significantly decreased percentage of calcium oxalate crystals while 0.50:0.50 ratio gave ـــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــless size of calcium oxalate crystals compare with control treatment (0:0) which decreased ascorbic acid and increased the percentage and size of calcium oxalate crystals in leaves and petioles ; when plant had grown at 10 and 15 true leaves stage.