Effect of crop density on yield and quality of alfalfa forage from combined use (forage-seed)

Abstract

In Serbia, alfalfa is the most important perennial forage legume that is grown at 180-200 thousand hectares. Except for the classic production of forage, alfalfa is very important for seed production. In our conditions Alfalfa seed are produced from the second cut of alfalfa. Higher seed yields are achieved in larger distances between rows. In this system of production first and third cut are used for fodder. This trial tests three different densities and four varieties in order to determine the impact on yield and quality of forage dry matter. In the year of establishment, cultivars from the treatment A1 achieved higher yields of dry matter for 2.3 t ha-1 in relation to the treatment A2. In the second year, yield was higher by 1.4 t ha-1, and in the third higher for 3.1 t ha-1. Treatment A1 compared to A3 treatment had a higher yield of 3.5 t ha-1 (52%). In the second year treatment A1 achieved higher yields of forage then treatment A3 for 3.8 t ha-1 (44%), and in the third year for 4.6 t ha-1 (56%). Cultivars were also significantly affected the yield of forage dry matter at all densities. Influence of density and variety to the chemical composition of forage and the content of macro elements in the forage had no significant effect.Lucerka, kao najznacajnija krmna leguminoza se u Srbiji gaji na 180-200 hiljada hektara. Osim klasicne proizvodnje za krmu, u sirokoj proizvodnji je uobicajeno da se lucerka koristi kombinovano za seme i krmu, pri cemu se prvi i treci otkos koriste za krmu, a drugi otkos za seme. Semenska proizvodnja zahteva manju gustinu biljaka u godini zasnivanja i malu kolicinu semena za setvu, medjutim, manja gustina useva utice na smanjenje prinosa krme u prvom i trecem otkosu. U ovom radu su ispitivane tri razlicite gustine i cetiri sorte lucerke Novosadjanka H-11 (B1); NS-Slavija (B2); Zajecarska-83 (B3) i francuska sorta Europe (B4), da bi se ispitala interakcija izmedju sorti, gustina i ekoloskih uslova na zadovoljavajuci prinos i kvalitet kako krme, tako i semena. Koriscenjem interakcije sorta h spoljna sredina moze se znacajno uticati na prinos suve materije krme pri svim gustinama useva. U poredjenju sa sortom Europe, sorte NS-Slavija i Zajecarska-83 su imale signifikantno veci prinos krme tokom sve tri godine i pri svim ispitivanim gustinama, sto se moze objasniti boljom adaptabilnoscu domacih sorti. Godine, gustina useva, sorta, kao i njihove interakcije nisu pokazale znacajan (p?0.05) uticaj na hemijski sastav i koncentraciju makroelemenata u krmi. Medjutim, iako nije statisticki znacajno ipak je na usevu iz gustorednog useva (tretman A) kod sorti NS Slavija i Zajecarska - 83 utvrdjen nesto bolji kvalitet krme. PR Projekat Ministarstva nauke Republike Srbije