Cercetări cu privire la comportarea unor specii de graminee şi leguminoase perene pe pajişti temporare înfiinţate pe bază de amestecuri complexe în Câmpia Moldovei

Abstract

The researches have focused on the behaviour of some species of leguminous plants and perennial graminaceae and their influence plants on the forage yield in complex mixtures. At the some time the authors have analysed the influence of fertilization with mineral and organic fertilizers on the species from the mixture and on the forage yield. From the mixtures under study, five were formed from six species, two perennial leguminous plants and four perennial graminaceae, and the other five mixtures were formed from seven species, from which two perennial leguminous plants and five perennial graminaceae. At the first five mixtures the perennial leguminous plants were represented by Medicago sativa and Lotus corniculatus, and the other five mixtures by Onobrychis viciifolia and Lotus corniculatus. The perennial graminaceae used in the first five mixtures were Dactylis glomerata, Festuca pratensis, Poa pratensis, Lolium perenne, and at the other five mixtures, the same species of graminaceae were used to which Bromus inermis was added. At the mixture were Medicago sativa has participated with 60 % in the sowing norm, the forage yield was about 4.37 t/ha d.m., at the mixture with 50 % Medicago sativa the yield was about 4.12 t/ha d.m. (94 %), and at the mixture with 20 % Medicago sativa the yield has decreased to 3.19 t/ha d.m. (73 %). At the group of the mixtures were Medicago sativa was replaced with Onobrychis viciifolia species and when Bromus inermis species was added to the graminaceeae, the yields were smaller. So at the mixture in which Onobrychis vicifolia has participated with 60 % in the mixture, the yield was about 3.25 t/ha d.m., and at the mixture with 20 % Onobrychis viciifolia the yield has decreased to 2.41 t/ha d.m. (74 %). The fertilization had a positive effect on the forage yield at all the mixtures under study, but the yields depended on the type of the mixture and on the fertilizers which were applied. The mixtures with Medicago sativa have reacted to fertilization more significantly than those with Onobrychis viciifolia.