Mahdipour Afra,R , , Amiri,R , and Iran Nejad,H . "Effect of polyethylene and organic mulches in different intervals of irrigation on morphological characteristics and grain yield of sunflower (Helianthus annus L.)", Journal Of Agroecology, 4, 3, 2012, 246-254. doi: 10.22067/jag.v4i3.15313