The effect of Irriigatiion ,, Pllant Densiity and Folliiar Boron on Growth ,, Yiielld and Qualliity of Sunfllower (Helianthus annuus L.)

Abstract

Two field experiments were conducted during the spring season of years 2010 and 2011 at special farm with clay loam texture soil , right bank of Euphrates river in Ramadi city .To study the effect of three factors(Irrigation, Plant density and foliar boron application) in growth and yield of sunflower (Helianthus annuus L. ) Akmar variety . A split -plots arrangement in randomized complete block design , with four replicates used for the two experiments . the first experiment comprised three irrigation treatments : irrigation at depletion 25%,50% and 75% of a available water in soil (I1 ,I2 ,and I3) , which occupied the main plots, while plants density included three treatments : 66666,83333 and 111111 plant/ ha (D1,D2 and D3) in sub plots. The second experiment also included two factors . Irrigation in three treatments (same treatments in the first experiment ) which occupied the main plots and foliar boron application in three levels : 0 , 1.2 and 2.24 Kg B/ha ( B1, B2 , and B3 ) in sub plots . The gravimetric method was used to continuation the moisture content at root zone to definition the actual evapotranspiration. The reference evapotranspiration was definition using Penman- monerath equation by region climatic data. The opposite equations were used to accounting crop coefficient and yield response coefficient . Results of the study can be summarized as follow : 1-The irrigation treatment I1 gave high rate for evapotranspiration in both experiments at the two study , superiored with highest relative water content , with increasing ratio 82.5% and 75.2% in comparison to I2 and I3 treatments respectively , and highest harvest index reached 3.5%and 14.4% in compaction to I2 and I3 treatment respectively I1 superintend in the many growth and Yield parameters , it gave highest plant (162 .4 cm) , leaf area (6210.2 cm) , plant dry weight (341 gm) , seed yield (4.16 ton /ha), oil yield (1. 72 ton /ha ) and number of seeds per head (1366.0 seed). And Yield response coefficient rate (Ky) increased with moisture tension , it ranged between 0.20- 0.45 at season, 2010 , and 0.31- 0.510at 2011 season .The values of this parameter were increased between 125% and 131% at I3 treatment in comparison with I2 treatment at 2010 and 2011 respectively, moisture tension was showed significant effect oil. Then I1treatment was superiority in Oleic and Lenoilic acids (32.6%)and (53.61%) receptivity . While highest values for Palmatic and Sterric acids (10.6% and 6.6%) respectively were recorded at I3 . ,