Determination of the Best Time of Sampling for Evaluation of Seed Bank Relation with Weed Density in Sugar Beet Using Regression Analysis

Abstract

Based on regression analysis and in order to specify the relationship between the population of the seed bank and the weed population in sugar beet farm, a study was conducted in the year 2009 in Motahari research center in Kamalshar (Karaj). The sampling from the seed bank was taken before planting the sugar beet as well as the weeds. The sampling from weeds was taken in three phases in two different sizes (50 × 50 cm) and (100 × 25 cm). In each piece of land, the population of the seeds of weeds and density of the bushes were separately identified and registered.  Based on findings, the highest amount of weeds was related to amaranth weed. The first sampling pointed out the highest amount of weeds as well as the highest co-efficiency with seed bank of amaranth weed. The regression analysis found out that there exists a higher co-efficiency in this phase of sampling in comparison with the whole three samplings. Hence, the first phase of growing which is so important based on controlling the weeds as well as critical period can be used to predict the population of weeds according to their seed density in seed bank.