The effect of meteorological factors on the productivity of catch crops in sustainable and organic farming systems

Abstract

The yield of Italian ryegrass, white mustard and winter rape was by 4.1, 2.0, 2.4 times in autumn and winter rape was by 1.8 times in spring lower than that of red clover. Field experiments were carried out for three years under the conditions of sustainable agriculture at the Lithuanian University of Agriculture's Experimental Station and under the conditions of organic agriculture in Kazli lciai organic farm. The study was aimed to evaluate the effects of climate factors on the productivity of different catch crop species ('Trifolium pratense L., Lolium multiflorum Lam., Sinapis alba L., Brassica napiis L.) under sustainable and organic farming systems. In both farming systems, climate factors had no effect on the productivity of undersown catch crops (red clover and Italian ryegrass). In the organic farming system, winter rape productivity was influenced by the duration of vegetation period (r = 0.89, P < 0.01), that of white mustard by the amount of precipitation (r = 0.81, P < 0.01) and hydrothermal coefficient (HTC) (r = 0.79, P < 0.05). In the sustainable farming system, climate factors had no effect on the productivity of post-harvest catch crops (white mustard and winter rape). The productivity of red clover, Italian ryegrass and winter rape was determined by crop density (strong and very strong correlations were established) in both farming systems. In the sustainable farming system, the productivity of the post-harvest catch crop species was more stable than that of the undersown catch crop species as the latter were suppressed by main crop (winter wheat) fertilized with mineral fertilizers and sprayed with pesticides. In the sustainable farming system, the highest dry mass yield obtained in autumn was that of white mustard (0.92 Mg ha 1), while the yield of red clover, Italian ryegrass and winter rape was lower - 29.3%, 59.8% and 37.0%, respectively. The yield of the aboveground dry mass in spring of red clover and winter rape was similar - 0.37 and 0.30 Mg ha 1 respectively. In organic farming the highest yield in autumn was that of red clover - 2.38 Mg ha 1.