عنوان مقاله [English]
In order to determine the optimum norms for nutrients in table grape cv. Shahroudi, an experiment was done in 54 vineyards in Shahroud region. The vineyards were grouped into low (n1= 41) and high (n2= 41) yielding groups using mathematical approach. Cumulative variance ratio function was used as cubic functions to obtain cutoff yield at 33.78 t ha-1 by mean calculation for high yielding samples. Preliminary CND norms were calculated as follows:
, ،=26.53,=35.43،,،، ، , ،.
Nutrient sufficiency norms were determined using mean results of high yielding grape tissue samples. The sufficiency norms included: N=2.56±0.436, P=0.57±0.150, K=1.04±0.149, Ca=1.26±0.392, Mg= 0.752±0.116, Mn=33.9±0.001, Zn=24.8±0.008, Fe=106.4±0.001, Cu=7.02±0.0001, B=43.6±0.0007, Cl=0.72±0.137. The data showed that due to high Cl level [H1] and general deficiencies in Ca, Zn, and N in the leaf, the related yields were low in the studied samples.
[H1]In soil or water?