Evaluation of Two Types of Cotton Pickers in Terms of the Functionality and Quality of the Harvested Fibers

Cotton, as one of the most widely used products in various industries, has always been considered by leading countries in agriculture. The applications of this plant range from the food industry to the military industry, as well as the textile and animal nutrition industry. It is predicted that by 2025, the area under cotton cultivation in the world will reach more than 33 million hectares (FAO, 2017). Based on the growing population, it is necessary to use machines in industries and other sectors to accelerate production and increase efficiency. Cotton is no exception to this rule. The use of a machine can play an effective role in reducing harvest costs and decreasing losses from frost and early fall rainfall by enabling timely harvesting.

Armaghan cultivar is an early-maturing cotton cultivar with high yield potential and good compatibility, introduced for conventional and secondary crops in Golestan, North Khorasan, Ardabil, and the central regions of Iran. The early maturity of this cultivar provides the possibility of cotton cultivation after wheat harvest in different regions of Iran. It reduces pests and diseases through the escape mechanism and completes the growth period in delayed planting. In this research, two types of picker machines were compared. One of the harvesting machines used in this study is a two-row self-propelled spindle picker machine, and the other picking machine is a two-row tractor semi-mounted dentate picker. Before harvesting with a machine, it is necessary to use a defoliator. This allows for seed cotton harvest with less trash and more cleanliness. About ten to fifteen days after spraying the defoliator, the leafless plants are ready for machine harvesting. In this study, the number of leaves was counted before spraying and before harvest, and the percentage of defoliation in each treatment was calculated and evaluated. The harvesting efficiency of machines, machine losses, and fiber qualities for each harvester was measured.

The results showed that the type of machine has a significant effect on plant residues and machine performance. However, the loss on the ground is not affected by the type of machine and remains almost the same for both machines. The mean comparisons revealed that the spindle harvesting machine leaves more than twice the amount of residues on the plant compared to the dentate harvesting machine. In terms of fiber quality, no significant difference was observed in any of the qualitative properties, and both machines perform at the same level.

The results of this research on the functional characteristics of picker machines and the cultivar and field conditions demonstrate that a higher percentage of leaves on the plant yields better performance from dentate picker machines compared to spindle pickers. Spindle pickers are sensitive to leaves due to the teeth on their needles, causing reduced efficiency in such fields. In contrast, dentate picker machines work well and perform better under these conditions. Based on this study, the dentate harvesting machine is more suitable than the spindle picker machine for harvesting Armaghan cotton cultivars.