Influence of agricultural land preparation on weed population in following crops: Thyme (Thymus vulgaris L.), Balm (Melissa officinalis L.), Lavender (Lavandula angustifolia L.) i Salvia (Salvia officinalis L.)

Abstract

In 2005 in Pancevo region (Serbia) we have conducted weed population monitoring in following crops: thyme (Thymus vulgaris L.), balm (Melissa officinalis L.), lavander (Lavandula angustifolia L.) i žalfije (Salvia officinalis L.). The first evaluation was obtained before and the second evaluation was obtained after agricultural mechanical land preparation. In each crop by random sampling method we have chosen several 1m2 areas. Plant population from each one of the areas was collected and fresh and dry weight for each plant was determined. In all four crops monitored we have found 35 different weed species. The highest weed population diversity was in salvia (35 species), followed by lavender (23 species), then thyme (20 species), and the lowest weed species diversity was in balm with only 16 weed species present. Among weed species found, highest numbers belonged to terophytes (13), followed by hemicriptophytes (12), and less present were geophytes (5) and tero-hemicriptophytes (12). Weed species in highest numbers present were: Convolvulus arvensis, Agropyrum repens, Cirsium arvense, Erigeron canadensis, Lactuca serriola and Polygonum lapathifolium. Species in highest numbers (C. arvensis and A. repens) were also species with highest fresh weight, followed by: Sonchus arvensis, Sorghum halepense, L. serriola i C. arvense.

U usevima timijana (Thymus vulgaris L.), matičnjaka (Melissa officinalis L.), lavande (Lavandula angustifolia L.) i žalfije (Salvia officinalis L.) rađena su florističko-fitocenološka snimanja korovske vegetacije. Prvo snimanje obavljeno je pre, a drugo posle ručne obrade zemljišta. U svakom od useva, po sistemu slučajnog uzorka, odabrane su površine od 1 m2 sa kojih je skinuta nadzemna masa biljaka i za svaku prisutnu vrstu izmerena sveža, a nakon vazdušnog sušenja i suva masa. U sva četiri useva konstantovano je 35 korovskih vrsta, pri čemu najviše u žalfiji 28, u lavandi 23, u timijanu 20, dok je u matičnjaku zabeleženo samo 16 vrsta. Među prisutnim vrstama najbrojnije su bile terofite (13), odmah iza njih hemikriptofite (12 ), a manje zastupljene su bile geofite (5) i tero-hemikripotofite (5). Od 35 utvrđenih vrsta u sva četiri analizirana useva sa najvećim ocenama za brojnosti i pokrovnost su bile: Convolvulus arvensis, Agropyrum repens, Cirsium arvense, Erigeron canadensis, Lactuca serriola i Polygonum lapathifolium. Vrste C. arvensis i A. repens koje po kvantitetu preovlađuju u korovskim zajednicama ispitivanog lekovitog bilja odlikuju se i najvećom svežom biomasom, a posle njih dolaze: Sonchus arvensis, Sorghum halepense, L. serriola i C. arvense.