Weed seed bank and dynamics in wheat as affected by sowing time and rice residue management methods Kaur Ramanpreet1, Deol JS1, Kaur Navjyot2, Kaur Simerjeet1,* 1Department of Agronomy, Punjab Agricultural University, Ludhiana, Punjab141004, India 2Department of Plant Breeding & Genetics, Punjab Agricultural University, LudhianaPunjab141004, India *Corresponding author email: simer@pau.edu
Online Published on 24 April, 2024. Abstract Field studies were carried out to evaluate the effect of sowing time and residue management methods of preceding rice varieties (with different residue load) on weed seed bank and density in wheat during Rabi 2019-20 and 2020-21 in Punjab. Experiment was conducted in split plot design keeping combinations of 2 preceding rice varieties with different residue loads and 2 sowing times in main plots and 4 residue management methods in sub-plots with 3 replications. Results revealed that weed population and biomass at 30 days after sowing was higher in fields with low residue load (6.96-7.89 t/ha of PR 126) as compared to high residue load (10.25-11.44 t/ha of PR 122). Population and biomass of Medicago denticulata was lower in 15th November sown wheat in contrast to other broad-leaf weeds. Lower density of Phalaris minor was recorded under early sown wheat (25th October). Weed density and biomass was lower under happy seeder as compared to other residue management methods. In mould board plough + rotavator treatment, weed seed per unit area was lower in 0-5 cm soil layer but it was higher at 10-15 cm soil depth as compared to other residue management methods. Crop growth parameters (plant height, tillers density and biomass) were not influenced by rice residue load and wheat planting time. Grain yield was recorded highest under early sown wheat as compared to late sown wheat. Grain yield was recorded highest under Happy Seeder as compared to other residue management system during second year. However, grain yield was recorded similar under all residue management methods during first year. The results suggested that grass weeds were less in 25th October sown wheat but 15th November sown crop has less broad-leaf weeds. Top Keywords Early sown wheat, Happy Seeder, Mould board plough, Residue burning, Residue removal, Rice varieties. Top |