Determination gap yield in product soybean on Aliabad katol are by use analysis CPA and bunderace liner

decres gap between actual yield and potencial yield (gap yield) is important way to incrace yield in unit. In order enhance yield, gap yield in any area determinted and factor participant be identified in gap yield in preduct crop plant. This investigation to order determination gap yield and limited factor to yield and contribution of each of them to soybean in Aliabad Katol area by using CPA method and boundary line analysis.

To carry out this study, Information on production management of 120 soybean farms in Aliabadabad district of Golestan province was collected in 2016. Management factors included field characteristics (area, previous crop, herbicides, previous crop, field position), seedbed preparation (type, number and time of tillage), sowing (amount of seed consumed, cultivar type, seed source, sowing date, Plant density), fertilizers and micronutrients (type of fertilizer, amount and timing of fertilizer application), pesticides (type and amount of herbicides and pesticides), use of biological control (Trichogram and Braun wasps), harvest (grain yield and harvest date). The yield was determined using CPA method and boundary line analysis.

The results showed that soybean yield potential in this region was 3921 kg / ha and soybean yield loss in Aliabad region was estimated at 30%. Delay in planting in this region was 8.4% of yield and suitable plant density of 15.5%, planting and seed consumption were 6.3% and 8.5% of seed yield, respectively. It was also found that not using herbicide before planting would decrease grain yield by 17.45%. According to the results, irrigation with 28.4% had the highest share in determining soybean production potential in the study area. The highest grain yield response to urea fertilizer application and irrigation was two-fold; increasing nitrogen up to 65 kg urea and 3 times irrigation increased grain yield and consuming greater than 65 kg ha-1 and more than 3 irrigation times. It did not change grain yield per hectare. The relationship between delay in planting and plant density with seed yield was dentate. 10-day delay in planting leads to increased yield, but yields maximum grain yield in fields that have 22 days past optimal sowing date.nsity with seed yield was dentate. 10-day delay in planting leads to increased yield, but yields maximum grain yield in fields that have 22 days past optimal sowing date.

In general, soybean yield in this area is related to resource limitation and crop management is second in importance, which can increase soybean production by 30% with proper irrigation and nitrogen use.