Assessment of different tillage systems on the soil weed seed bank in rainfed wheat (Triticum aestivum L.) in arid zone of Pakistan

Weeds reduce the potential yield of many crops as they are the host of many pests and diseases that ultimately deteriorate the quality and quantity of the produce. Therefore, this study was conducted to determine the weed seed bank in arid zone area of Pakistan. This study reports the results of a 2 years experiment that was carried out at University Research Farm, Chakwal Road, Rawalpindi to assess weed seed bank response against different tillage systems in rain fed wheat. Experiment was arranged in Randomized Complete Block Design (RCBD) with four tillage treatments repeated thrice. These tillage treatments i.e. T1 = conventional tillage (farmer's practice), T2 = zero tillage, T3 = disk harrowing + glyphosate + direct seeding and T4 = chiseling + glyphosate + direct seeding were applied in kharif season, 2013 (Kharif crops are those crops which are grown on the onset of monsoon season i.e. from July to October each year) just after harvesting of wheat crop of previous rabi season, 2012-13 (Rabi cropping season is from October to March each year). Soil samples for weed seed bank analysis were collected periodically from three soil depths i.e. 0-10 cm, 11-20 cm and 21-30 cm at three stages i.e. pre cultivation, pre sowing and post harvesting stages. The results demonstrated that higher seed species density, weed species diversity, species frequency, dominant weed seed species, relative density, relative frequency, relative importance of species, temporal distribution of species were reported at post harvesting stage as compared to pre-cultivation and pre-sowing stages. This study would enable us to find the clear picture of the weed seed bank present in these soils to design future weed management strategies.