Majid Rahimizadeh
Abstract
A field experiment was conducted to evaluate and compare the effects of N and P chemical fertilizers with biological N and P fertilizers on competition between cotton and weeds with split plot arrangement in a randomized complete block design with three replications during the years 2014 and 2015. The ...
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A field experiment was conducted to evaluate and compare the effects of N and P chemical fertilizers with biological N and P fertilizers on competition between cotton and weeds with split plot arrangement in a randomized complete block design with three replications during the years 2014 and 2015. The main plots consisted of two levels of weed management practices including weed free and weedy check. Sub plots had five treatments included integrated application of biological and chemical fertilizers:1-Control (Without fertilizer) 2-Urea+Triplesuperphosphate (TSP) 3-Nitroxin+50% urea+100% TSP 4-100% urea+Barvar2 +50% TSP 5-Nitroxin+Barvar2+50% urea+50% TSP. In the first year, control of weeds increased LAI and number of boll per plant to 34 and 22 percent, respectively and cotton yield increased by 67 percent in the first year and 50 percent in the second year. Fertilizer treatments had a significant effect on stem length, LAI, number of sympodial branches and boll per plant, and yield of cotton. Under weed interference condition, use chemical fertilizers alone reduced cotton growth and yield due to increasing competitive ability of weeds. But reducing urea consumption by half and replace it with nitroxin, increased cotton yield by 61% compared to the chemical fertilizer treatment due to increasing number of boll per plant. This result indicates that the use of biological fertilizers reduce the negative effects of chemical fertilizers and increase crop competitiveness against weeds
Parastoo Pahlevanloo; Majid Rahimizadeh; Mohammad Reza Tookalloo
Abstract
In order to investigation nitrogen use efficiency in intercropping of maize and soybean an experiment was conducted with split plot arrangement in a randomized complete block design with three replications in 2012 in Bojnourd (North Khorasan). Nitrogen fertilizer rate was as a main factor at three levels ...
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In order to investigation nitrogen use efficiency in intercropping of maize and soybean an experiment was conducted with split plot arrangement in a randomized complete block design with three replications in 2012 in Bojnourd (North Khorasan). Nitrogen fertilizer rate was as a main factor at three levels (control, 50 percent lower than recommended N rate, recommended N) and five mixing ratio treatments were (0:100, 50:50, 66:33, 100:0 and 100:25 corn and soybean) as subplots within the main plots. Results indicated that nitrogen and intercropping system had significant effect on yield and nitrogen use efficiency. Nitrogen fertilizer increased nitrogen use efficiency, economical yield and land equivalent ratio. The highest nitrogen use efficiency, economical yield and land equivalent ratio were obtained in mixture of 50:50 corn and soybean under nitrogen recommended rate that 131, 16 and 21 percent higher than sole cropping, respectively. Therefore, intercrops could be used for more efficient use of N on a per land area basis.