Effect of different agronomic managements on quantitative and qualitative yield of wheat cultivars

Introduction
Wheat is the first grain and the most important crop in the world and is one of the major agricultural products that meet the nutritional needs of humans in different countries. developing the use of renewable plant and animal resources and biological resources instead of chemical resources, can play an important role in fertility and maintenance of biological activities, increasing soil organic matter, crop ecosystem health and increasing the quality of crops. According to this, the aim of study is Comparison of crop systems based on wheat cultivation in order to identify and select the best and least dangerous system and agronomical management for the environment. The use of organic fertilizers can also be an effective step to reduce the effects of chemical fertilizer abuse and improve the physicochemical properties of the soil. The use of organic fertilizers can also be an effective step to reduce the effects of chemical fertilizer abuse and improve the physicochemical properties of the soil.While in intensive cropping systems, soil organic matter and nutrients are rapidly depleted and concentrated use of chemical fertilizers reduces crop yields. And this reduction in yield is due to the reduction of biological activity and unfavorable physical properties of soil and the absence of high-consumption fertilizers from trace elements.



Materials and Methods
The experiment was done as split plot in randomized complete blocks design with three replications at Shahid Chamran University of Ahvaz. the main factor included different of ecosystems (low input, medium input and high input) and the sub-factor included different wheat cultivars (Mehregan, Chamran-2 and Shabrang). Planting was done manually on November 18, 2018. each plot consisted of 8 planting lines and was approximately three meters long and two meters wide. The distance between the lines was 20 cm and the distance between the plants on the lines was 2 cm. statistical analysis of data was performed using SAS software version 9.4 and mean comparison was performed by Duncan's multiple range test method.
Results and Discussion
The results showed that the difference between ecosystems levels on number of spikes, number of grains per spike, spike length, 1000-grain weight, grain yield, grain nitrogen, grain protein, phosphorus and grain potassium was significant at 1% probability level and in wheat cultivars on number Spike, spike length, 1000-grain weight, grain yield, phosphorus and potassium were significant at 1% probability level. In interaction, number of spikes, number of seeds per spike, 1000-seed weight, grain yield and grain phosphorus and potassium were significant at 1% probability level. the highest grain yield in high-input management system and Chamran-2 cultivar (6312 kg/ha) and high-input and Mehregan cultivar (6240 kg/ha) and the lowest in low-input management system and Shabrang cultivar (4289 kg/ha) and low-input and Chamran-2 cultivar (4375 kg/ha). The highest percentage of grain protein was in the low-input and medium-input (integrated) management system with 12.6% and the lowest in the high-input management system with 10.5%. as a result, by using organic inputs, it has produced lower yield but higher quality (grain protein and phosphorus).
Conclusion
In general, the results showed that the high-input agricultural ecosystem produced higher yields for all cultivars used in the experiment using a higher level of synthetic chemical inputs. In contrast, low-input (organic) agriculture, using organic inputs, has produced lower yields but higher quality (increased grain protein and grain phosphorus). Overall it is suggested that the best ecosystems are medium-input (integrated) ecosystems and Chamran-2 and Mehregan cultivars.