Influence of soil preparation, seed size and planting depth on sweet sorghum emergence

Abstract

The present work aimed to study the influence of soil preparation, seed size and planting depth in sweet sorghum (Sorghum bicolor L. Moench) emergence in field conditions. The experiment was conducted in 1981/82 at EMBRAPA/UEPAE de Pelotas, at Pelotas, RS, Brazil. Soil preparation treatments were: A₁ = 1 disc plow+ 1 disc grading+ 1 tooth harrow; A₂= 1 disc plow+ 2 disc gradings + + 1 tooth harrow; A₃ = 1 disc plow+ 1 disc grading. 2 tooth harrows. Seed size were of three classes: B₁ = seeds bigger than 3.97 mm; B₂ seeds under 3.97 mm; B₃ - mixture of seeds of equal quantity, in weight, of B₁ and B₂. Planting depth treatments were: C₁ = 1.5 cm; C₂ = 3.5 cm; C₃ = 5.5 cm; C₄ = 7.5 cm. Soil preparation and seed sire didn't show any influence in seedling emergence for all treatments. Planting depth had an important influence in seedling emergence due to the soil moisture content in the planting date. Depth 3.5 cm and 7.5 cm gave the highest percentage of germination and the fastest emergence, respectively. Through regression analysis, the optimum planting depth estimated was 4.83 cm.