Competition for nutrients between weeds and potato

Competition between potato and weeds was examined in a field trial. Samplings were made after flowering of potato. Potato and weed samples were collected from 1 m(2) sampling areas from the untreated (weedy) control plots. Each weed species were examined so their role in the competition for nutrients could be also studied. Shoot and tuber weight of potato considerably decreased because of the competition. Higher decrease could be observed in the fresh weight than in the dry weight because of competition especially in the case of tubers. Because of competition, tuber weight decreased in higher rate than the shoot weight. Based on our results we have found that the nutrient uptake of the weeds was significant. On the weedy plots weeds have taken up 4.35 g nitrogen, 0.26 g phosphorus and 3.10 g potassium altogether. These nutrient quantities correspond to 43.5 kg ha(-1) nitrogen, 2.6 kg ha(-1) phosphorus and 31 kg ha(-1) potassium.