Dynamic indices and yield of sweet corn under subsurface drip irrigation system

Water shortage is the most important factor in reducing the yield of agricultural products all over the world and this factor is more effective in arid and semi-arid regions. Iran is a country whose average rainfall is about one-third of the global average, and in terms of water resources, it is in dire straits. Therefore, it is necessary to help preserve limited water resources by optimal use, saving and increasing irrigation efficiency. This research was defined according to the consumption of the strategic product of corn and the importance of managing the country's limited renewable water resources, on top of that, the use of pressurized irrigation systems in the region and in the climatic conditions of Urmia.

In order to investigate different levels of irrigation on performance indicators and plant traits of sweet corn, under the subsurface drip irrigation system in the form of a complete randomized block design with four treatments of 20% over-irrigation, equal to the water requirement, 20 and 40% under-irrigation in four replicates in the research farm of the Engineering Department. water of Urmia University. The plant index values of stem diameter, leaf area, grain yield, number of leaves per stem, biological yield (wet), plant dry matter and cob yield during the growing season on specific dates and also on the day of harvest. was taken and evaluated.

The results showed that in general, the effects of under-irrigation and over-irrigation on biological yield, dry matter, uncoated cob yield, 300 seed weight, number of leaves and stem diameter were significant. Also, based on the results, it can be stated that with the reduction of water consumption, the cob yield decreases linearly. The highest and lowest cob yields were obtained in overwatering and 60% water requirement treatments with an average of 1.83 and 1.13 kg/m2, respectively.

In general, under-irrigation and over-irrigation have a significant effect on biological yield, dry matter, uncoated bale yield, three hundred weight, number of leaves and stem diameter. Also, based on the results, it can be stated that with the reduction of water consumption, the quantity of cobs decreases linearly. The highest and lowest cob yields were obtained in over-irrigation and 60% water requirement treatments with an average of 1.83 and 1.13 weight per square meter, respectively. According to the results of the research, with a 20% reduction in water consumption compared to full irrigation, only 5.02% of the biomass weight is reduced, apart from significance. Control (equal to water requirement) and 20% less irrigation in dry matter traits, uncoated cob yield, 300 seed weight, number of leaves and stem diameter, no significant difference was observed. The process of changes in the accumulation rate of biological yield of sweet corn initially started from 21 days after planting and after 6-9 days it entered the linear growth stage and then continued steadily. The highest weight of biological yield of sweet corn in different treatments was observed in 87 days after planting.