نوع مقاله : مقاله کامل علمی- پژوهشی
نویسندگان
1 دانشگاه کشاورزی و منابع طبیعی خوزستان
2 دانشگاه علوم کشاورزی و منابع طبیعی خوزستان
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Background and Objectives: Wheat, as a strategic crop, plays a pivotal role in national food security. One significant factor reducing wheat yield is the presence of weeds. Extensive reliance on chemical methods for weed management in wheat has led to a major challenge: the emergence of herbicide-resistant weeds. In integrated weed management, cultural practices can be effective in reducing the seed bank and controlling weeds. Utilizing cultural methods such as fertilizer management, especially nitrogen, as well as seedbed preparations (false and stale seedbed) can be promising. This research aims to assess the effects of different fertilization levels and seedbed preparations on weed biomass and wheat yield and yield components under Khuzestan weather conditions.
Materials and Methods: The experiment was conducted as a split-plot design based on completely randomized block design (RCBD) with three replicates. Different seedbed systems included: 1. Conventional seedbed preparation (plowing, discing, leveling, and planting in the second week of December) 2. Stale seedbed with permanent ridges using paraquat herbicide 4L/ha 3. Stale seedbed with glyphosate herbicide 6L/ha 4. Stale seedbed with flaming 5. False seedbed with non-permanent ridges using a cultivator (Tiler). The sub-plots included different nitrogen fertilizer levels (0, 100, 200, and 300 kg/ha of urea 46%, equivalent to 0, 46, 92, and 138 kg/ha of pure nitrogen respectively).
Results: The results indicated significant differences in weed biomass between seedbed treatments and different nitrogen fertilizer levels. The highest total weed biomass (73.96 g/m²) was observed under 300 kg/ha fertilizer in the stale seedbed with flaming application, while the lowest total weed biomass (6.37 g/m²) was obtained under 100 kg/ha fertilizer in the stale seedbed with paraquat.
Moreover, the results showed the highest number of grain per spike (49.5) was in conventional seedbed preparation with 200 kg/ha fertilizer, and the lowest (31) was one under stale seedbed with flaming and no nitrogen application. The comparison of means for 1000 grain weight across different nitrogen fertilizer levels and seedbed treatments showed the highest thousand grain weight (41.30 g) was observed in conventional seedbed preparation, with the highest weight (40.27 g) among nitrogen levels at 300 kg/ha. The maximum wheat grain yield (5249 kg/ha) was recorded in conventional seedbed preparation with 300 kg/ha nitrogen application, while the lowest grain yield (2852 kg/ha) was in the false seedbed with flaming treatment and 300 kg/ha nitrogen application. The research demonstrated that different seedbed preparations, particularly stale seedbeds with application glyphosate and paraquat, were successful in reducing the seed bank and weed biomass compared to cultivator and flaming treatments. However, due to delayed planting in the stale and false seedbeds, the reproductive phase coincided with heat stress, significantly reducing the number of seeds per spike and 1000 grain weight of wheat.
Conclusion: This study concluded that under inadequate weed control conditions (flaming application), application of higher nitrogen fertilizer levels such as 300 kg/ha significantly increased weed biomass and reduced wheat traits. Timely sowing and proper fertilizer management can improve wheat's competitive ability against weeds, serving as a non-chemical tool for integrated weed management.
کلیدواژهها [English]
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