Effect of Weeds and Some Methods for their Control in Seed Production Stands of Sainfoin (Onobrychis viciifolia Scop.)

Abstract

During the 2007-2009 period in the experimental field of the Institute of Forage Crops a study was conducted with the purpose of investigating the effect of weeds and some methods for their control in seed production stands of sainfoin (Onobrychis viciifolia Scop.). The trial was carried out on a slightly leached chernozem on an area with a natural background of weed infestation. As a result of the study it was found: Establishment of very uniform and productive seed production stands of sainfoin required effective weed control concentrated mainly in the first year when the degree of weed infestation was the highest and reached to a number of 245 plants/m2 and the fresh weed biomass to 1311 g/m2. The chemical control method showed the highest efficacy had the highest efficiency when, in the year of stand establishment at the stage of second-fourth true leaf of sainfoin, the treatment was conducted with imazamox 40g/l (Pulsar 40) at the dose of 48 g a.i./ha or with the system of Bentazon 600 g/l (Basagran 600 SL) – 900 g a.i./ha – fluazifop-P-butyl g/l (Fusilad Forte) – 120 g a.i./ha. In the years of seed production in spring at the beginning of vegetation, the treatment was conducted with imazamox 40 g/l (Pulsar 40) at the dose of 20 g a.i./ha + adjuvant DESH at the dose of 1000 ml/ha. An alternative to the chemical method is to sow sainfoin under cover of spring barley achieving more complete use of the area in the first year, a weed suppressive and ecological effect, but some negative residual effect on the crop was also observed; The pure stands of sainfoin with chemical control of weeds had the highest seed productivity, exceeding the zero check by 24 to 28%, followed by the stands with spring barley as a cover crop with an increase of 12% and the mixed stands of sainfoin with crested wheatgrass had the lowest productivity.

U periodu 2007-2009. godine na eksperimentalnim parcelama Instituta za krmno bilje, Pleven, Bugarska, ispitivan je uticaj korova i nekih metoda njihovog suzbijanja na proizvodnju semena esparzete (Onobrychis viciifolia Scop.). Istraživanja su obavljena na zemljištu tipa degradirani černozem pri zatečenom nivou zakorovljenosti parcela. Na osnovu rezultata istraživanja može se zaključiti sledeće: • zasnivanje uniformnih i visokoproduktivnih useva za proizvodnju semena esparzete zahtevalo je efikasno suzbijanje korova, prvenstveno u prvoj godini, kada je stepen zakorovljenosti bio najveći i dostizao 245 biljaka/m2, a sveža biomasa korova 1311 g/m2; • hemijsko suzbijanje korova je bilo najefikasnije u godini zasnivanja useva i u fazi kada je esparzeta imala 2-4 lista, tretiranjem imazamoksom 40 g/l (Pulsar 40) u količini 48 g a.m./ha ili mešavinom Bentazon 600 g/l (Basagran 600 SL) – 900 g a.m./ha – fluazifop- P-butyl g/l (Fusilad Forte) – 120 g a.m./ha. U godinama proizvodnje semena, na početku vegetacije u proleće, hemijsko suzbijanje je rađeno imazamoksom 40 g/l (Pulsar 40) u količini od 20 g a.m./ha + okvašivač DESH u količini od 1000 ml/ha; • alternativa hemijskoj metodi suzbijanja korova je setva jarog ječma kao pokrovnog useva. U ovom slučaju je postignuto suzbijanje korova ali su zabeleženi negativni rezidualni efekti na usevu; • produktivnost proizvodnje semena je bila najveća (24-28%) pri hemijskom suzbijanju korova u usevu esparzete, nešto manja (12%) pri setvi jarog ječma kao pokrovnog useva, a najmanja u usevu esparzete i češljaste pirevine.