Cost efficiency of different cropping systems encompassing the energy crop Helianthus annuus L.

E. Skoufogianni, K.D. Giannoulis*, D. Bartzialis and N.G. Danalatos

University of Thessaly, Department of Agriculture, Crop Production & Rural Environment, Fytokoy street, 38443, Volos, Greece
*Correspondence: kyriakos.giannoulis@gmail.com

Abstract:

Crop rotation and green manure are the most ancient and popular cropping systems. This study sought to analyze the economic efficiency of sunflower where pea (Pisum sativum L.) either harvested or incorporated at the flowering stage in the soil before the sowing of sunflower in Europe and the final agricultural profit of such a cultivation system. Therefore, the main objective of this paper is to report the production costs and to find out which of the tested cultivation system gets sunflower cultivation economically viable in Greece and in Mediterranean region. To assess the economic efficiency, three-year field experiments were established in two contrasting environments in central Greece (Trikala and Larisa) and contained three different cultivation practices using legumes comprised the main-factor (T₁: control, T₂: legume incorporated at the flowering stage, T₃: legume incorporated after seed harvest), while nitrogen fertilization comprised the sub-factor (N₁:0, N₂:50, N₃:100 and N₄:150 kgNha^-1). The results derived from this study revealed the positive effect of the legume incorporation treatment (T₂: legume incorporated at the flowering stage) where the final yield increased up to 5 t ha^-1 regardless region. Moreover, depending on the year the T₂ treatment increases the final yield 30–50% and a yield increase was also noticed to the treatment where the legume was harvested (T₃: legume incorporated after seed harvest). Therefore the introduction of this scheme into future land use systems in Greece and more generally in Mediterranean basin should be seriously taken into consideration.

Key words:

green manure, monocrop, pea, rotation, sunflower

The influence of short crop rotations on weed community composition

V. Seibutis and I. Deveikyte

Lithuanian Institute of Agriculture, Instituto aleja 1, Akademija, Kedainiai distr., LT-58344,Lithuania; e-mail: vytautas@lzi.lt, irenad@lzi.lt

Abstract:

Field experiments were designed to evaluate the effect of crop rotations on weed density and species composition. An 8-year study was initiated in Dotnuva (Lithuania) in 1997 on an Endocalcari-Endohypogleyic Cambisol. Ten crop rotations: peas–winter wheat–sugar beet–spring barley, peas–winter wheat–spring barley, peas–winter wheat-winter wheat, sugar beet-spring barley-winter wheat, sugar beet-peas-winter wheat, sugar beet-spring barley-peas, sugar beet-spring barley-spring rape, peas-winter wheat, sprig barley-sugar beet, winter rape-winter wheat and spring barley monocrops were investigated. It was revealed that weed densities varied between rotations. In winter wheat crops in all crop rotations the density of Fallopia convolvulus was high but there was less Lamium purpureum, Myosotis arvensis and Stellaria media at the end than at the beginning of crop rotations. The density of Elytrigia repens was high in most crop rotations investigated. The exception was crop rotations where sugar beet was involved, compared to a four-course rotation. The largest total of annual and perennial weeds was recorded in winter wheat, when the crop was grown after peas and winter rape. In all crop rotations, in the stands of spring barley the amount of Lamium purpureum, Tripleurospermum perforatum and Taraxacum officinale was 13–18% lower compared with the spring barley monocrop. Annual broad-leafed weeds in the spring barley monocrop were more numerous than in a four-course rotation but less numerous than in the other crop rotations.

Key words: