Effect of different levels and timing of boron foliar application on growth, yield and quality of sunflower genotypes (Helianthus annuus L.)‎

الملخص EN

Two field experiments were conducted at AL-Rashidia Location, west north Mosul city, Nineveh province, during two successive growing of 2008 : spring and autumn, in a sandy Loam soil to study the response growth, yield and quality of four sunflower genotypes to boron levels and timing of foliar application.

Each experiment comprised four sunflower genotypes (Euroflor, Record, Coban and ALbena), three levels of boron foliar application (0،3 and 6 mg.

l-1), and three timing of boron sprayed on the plant leaves one dose during (6 leaves stage, budding stage and 50 % flowering stage).

They were conducted according to randomized completely block design with split-split plot with three replications.

Results showed that the genotype Euroflor gave a high mean values of leaf area, head diameter, number of seeds / head, 1000 seed weight, seed yield and oil yield, while Albena genotype gave a high value of seed oil percentage for both seasons spring and autumn respectively.

Boron sprayed on the plant leaves with concentration 3 mg.

l-1 led significant increase in leaf area, head diameter, number of seeds/ head, 1000 seed weight, seed yield and oil yield, while increasing concentration of boron to 6 mg.

l-1 increased seed protein percentage and protein yield.

Delaying timing of boron foliar application to budding stage achieved highest values for most characters.

Interaction genotypes x boron levels gave significant increase in leaf area, head diameter, number of seeds / head, 1000 seed weight and seed yield.

Similar result were obtained from the interaction between boron levels x timing of boron application , further more, the same trend was recorded for seed oil percentage parameter.

Moreover, genotypes x time of boron application, genotypes x boron levels x time of boron application had a significant affect on some characters under study.