1 Sunflower (Helianthus annuus L.) is native to North America. American natives first cultivated sunflower 5000 yr ago in the present-day southwest United States (Semeslczi-Kovacs, 1975). Sunflower spread to the north and east in North America, where it was domesticated 4000 yr ago (Blackman et al., 2011). Sunflower is a relatively new commercial crop to the United States, with commercial culti...

This research was carried out to evaluate the effect of drought stress on grain yield and qualitative traits in some Iranian landraces of confectionary sunflower. Fifty six confectionary sunflower landraces were evaluated using three different water treatment conditions with three separate rectangular 7 × 8 lattice design with two replications. Irrigation treatments were as follows optimum irri...

In hybrid sunflower, bee pollination can improve productivity, but the contribution of bees to productivity may be over or underestimated. To estimate effects (seed trait gains from exposure during anthesis), single capitula are commonly covered with a porous material exclude bees. However, depending on exclosure porosity, estimates magnitude will vary. two studies, porosity size and effect in ...