تأثير الكثافة النباتية و مستوى إضافة الكبريت الزراعي في نمو و غلة محصول زهرة الشمس تحت الظروف الجافة غربي العراق

الملخص EN

The decline per unit area of sunflower productivity in Iraq in comparison with the world sunflower productivity is important and required to be studied in order to exploit the different environment factors (soil, water, light, temperature, fertilization, etc.) in an optimum way to improve production both quantitatively and qualitatively.

A field trial was carried out in the province of AL-Anbar in Iraq according to split plot design in complete'randomized blocks.

The aim of the study, which lasted two years, was to determine the effect of two important factors on the growth and productivity of the sunflower crop (Euro flower variety), namely plant density with five levels (71428, 83333, 100000, 125000, 166666 plant/ha) and agricultural sulfur application with four levels (0.00, 0.75, 1.50, 2.00 Meq.S/ha).

The increase of plant density led to a significant increase in plant height whereas dry plant weight, the capitulum’s diameter and the number of seeds per capitulum decreased.

The total seed yield increased.

The application of agriculture sulfur to the calcic soil significantly decreased the degree of soil pH and this was accompanied by a significant increase in the soil nitrogen (N) and available phosphorus contents, which reflected positively in the quantity absorbed by plant.

The increase of plant height, leaf area and plant dry matter led to the increase of the capitulum’s diameter, the total seed yield and the oil seed content.

The interaction between the two factors significantly affected the studied traits.

The plant density treatment 166,666 plant/ha and the treatment with sulfur application at 2.00Meq Sْ/ha significantly highlighted these traits compared with the treatment with 7141428 plant/ha without sulfur application which demonstrated the lowest performance.

The study showed the possibility of increasing plant density of the crop via applying agricultural sulfur as an amendment to the soil to obtain the best quantity and quality of seeds.