Foliar application effect of gibberellic acid on growth, yield components and some qualitative characteristics of linseed (Linium usitatissimum L.)

Abstract

Understanding the effects of spraying five levels of gibberellic acid (0,125,250 375 and 500) mg L -1 on growth, yield and quality of two flax cultivars (Syrian local and Poland), using factorial randomized complete block design (RCBD) by three replications which was applied as experimental design, at Grdarasha experimental field of the College of Agricultural Engineering Science, Salahaddin University, Erbil, with GPS reading of (Latitude 36. 10116 N and Longitude 44.00925 E), and elevation of 415 meter s above sea level. The statistical analysis indicated to significant effect of both factors and their interactions on most of the studied traits, foliar application of gibberellic acid caused significant increase in seed yield (Mg ha -1 ), biological yield (Mg ha -1) , HI %, oil % and oil yield (Mg ha -1 ) which were the highest values about (1.69, 7.01, 24.28, 46.10 and 0.78), respectively recorded by applying 500 mg L -1 of GA3. The highest values of all growth and seed yield characteristics; plant height, fruit length, no. of branch, stem width, no. of capsules plant -1 , seed yield and HI by (51.48 cm, 31.08 cm ,7.30 branches plant -1 , 2.58 mm, 29.98 capsules plant -1 , 1.34(Mg ha -1 ) and 20.61%) respectively were obtained from Poland cultivar. The highest values (22.16, 18.63, 0.44, 5.58 and 7.25) % for oleic, linoleic, linolenic, palmitic and stearic acid respectively which were recorded from the interaction treatment of GA3 (375 mg L -1 ) x Syrian Cultivar. Strong positive correlation was found between seed yield to each of (plant height (cm), fruiting stem (cm), number of branch plant -1 , stem width (mm), number of capsule plant -1 , number seed capsule -1 , seed index (g), harvest index %, oil yield (Mg ha -1 ) with the correlation coefficient(r) values of (0.87**,0.86**,0.89**.0.81**,0.79**,0.77**,0.98** ,0.96**and 0.99** .