Effect of density and arrangement of plants on sunflower. I. Achene and oil yields, oil percent and yield components

Abstract

With the objective of evaluating the effect of sunflower (Helianthus annuus L.) cv. Contisol 711 plant density and arrangement of plants on achene and oil yields, oil percentage and yield components, a research was conducted at Guaíba, RS, Brazil, during the 1983/84 growing season. Populations of 25.000 and 60,000 plants/ha were tested in five arrangements: two single row spacings, 100cm and 70cm apart; two double-row systems spaced 150cm and 200cm apart (50cm between rows in the double rows); and one system with plants uniformly spaced within and between rows, 63 cm and 45 cm apart respectively to 25,00 and 60,000 plants/ha. Grain and oil yields were higher with 50,000 than with 25,000 plants/ha. On the other hand, plants at the lowest population presented higher thousand-achene weight and number of achenes per head. The highest grain and oil yields were obtained with single rows and plants uniformly spaced, in relation to double rows. Thousand achene weight and number of achenes per head were lowest in double rows. The oil percent in the achenes was not affected by plant density and arrangement of plants.