Investigation of Species Diversity and Functional Structure in Weed Community in Apple Orchard of Fariman

In order to investigate the species and functional diversity and the structure of weed communities in apple orchards in Fariman, 48 orchards were studied in 2010. At first, all orchards based on the amount of used input (gathered by questioner were divided to 3 groups: high input, medium input and low input. Then weed population samples were collected. After sampling, weed density, frequency percentage and evenness coefficient were determined based on genus and species separation. The results showed that weed community in different orchards are composed of 54 species in 17 plant families. Among the community, 45 species were dicotyledonous and 9 species were monocotyledons. Also, 48 species were C3 plants and others were C4 species. They were 40 annuals and 14 perennials. Asteraceae, Fabaceae and Chenopodiaceae families had the most diversity among dicotyledonous and Poaceae, with the most diversity, was among monocotyledons. Shannon- Weiner index varied between 11.35 and 2.73; high-input orchards had the most species diversity in Shannon index. The investigation of elative frequency amounts in different orchard groups indicated that weed species density was affected by different weed management systems.