The Effect of Different Tillage Methods and Application of Plant Residues on Yield, Protein and Nitrogen Percentage of Triticale Plant (X Triticosecale Wittmack) and Physical and Chemical Indicators of Soil

Introduction Tillage is an important component of soil management that affects the production of crops. Maintaining and improving the quality of the soil is a basic requirement to ensure the sustainability of the ecosystem. This experiment was conducted in order to investigate the effect of different tillage methods and the use of plant residues on the yield, protein and nitrogen percentage of triticale plant and physical and chemical indicators of the soil. Materials and MethodsThe experiment was carried out as split plots based on a randomized complete block design with three replications at Shahid Chamran University of Ahvaz during 2023-2024. The main factor including different methods of tillage at three levels (conventional tillage, reduced tillage and no tillage) and the sub factor also including 5 levels of plant residue application (without residues (control), wheat residues, mung bean, sesame and half of wheat residues + half of residues Mung bean) were considered. The amount of residues used for each plot was approximately 30% of the biological yield of the product, which was considered to be 3, 1.5 and 1 ton.ha-1 for wheat, sesame and mung bean, respectively. At the end of the experiment yield and yield components, seed nitrogen and protein of triticale plant and physical characteristics (bulk density, percentage of porosity) and chemical (pH, EC, organic carbon content, nitrogen) soil properties were measured. All statistical calculations were made using SAS 9.3 statistical software and for the LSD test was used to compare the means at a probability level of 5%. Results and DiscussionThe interaction of tillage treatments and the use of plant residues showed that the highest grain yield was equal to 8.6 ton.ha-1 from the treatment of reduced tillage and the use of Mung bean residues, and the lowest value obtained was related to the effect of the treatment conventional tillage and no residues (control) with 3.5 ton.ha-1. The grain yield in the reduced tillage method was 12.5% and 7.6% higher than the conventional tillage and no tillage methods. The reduced tillage method resulted in a 32.2% increase in seed protein and a 32% increase in seed nitrogen compared to conventional tillage. The results also indicated a significant interaction effect between tillage treatments and residue application on grain yield (p < 0.01). Additionally, the interaction between tillage and residue application had a significant effect on soil bulk density (p < 0.01). The lowest bulk density (1.3 g.cm-3) was observed in the conventional tillage treatment combined with wheat and mung bean residues, with this combination falling within the same statistical group. The highest bulk density (1.75 g.cm-3) was obtained from the no-tillage treatment and the use of NO residues (Control). Based on the obtained results, the interaction effect of tillage treatments and the use of residues on soil organic matter, soil organic carbon and nitrogen soil (p<0.05). The interaction between the effects of tillage and the use of residues showed that the highest soil organic matter (1.53%) was from the treatment of reduced and the use of wheat residues. ConclusionThe results showed that tillage methods and the use of plant residues, in addition to affecting the percentage of nitrogen and protein of triticale seeds, also affected the physical and chemical indicators of the soil. The changes related to the physical and chemical indicators of the soil in the method No tillage are more than the two methods of reduced tillage and conventional tillage, and the improvement of these characteristics has been limited even at this time. Overall, from the point of view of soil protection, the results of this experiment clearly show the superiority of conservation tillage methods compared to conventional tillage methods. Sustainable agriculture aims to achieve optimal yields while preserving environmental structure and minimizing the adverse impacts of agricultural activities. One of the key challenges in sustainable agriculture is the lack of organic matter and its associated consequences. Implementing conservation tillage and managing plant residues-critical elements of agricultural production-can help address this issue. By improving soil quality, these practices contribute to increased productivity in farming. Acknowledgement We would like to thank the Research and Technology Vice-Chancellor of Shahid Chamran University of Ahvaz for funding this research, which is part of the research contract SCU.AA1400.309.