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Water and Nitrogen Response Characteristics of Hybrid Cotton under Drip Irrigation

Author: QiTong
Tutor: HouZhenAn
School: Shihezi University
Course: Crop Cultivation and Farming System
Keywords: Pour Hybrid cotton Fertigation frequency Nitrogen Uptake Yield
CLC: S562
Type: Master's thesis
Year: 2009
Downloads: 34
Quote: 0
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Abstract

Water and nitrogen in arid - semi-arid areas affected major limiting factor in agricultural production, improve agricultural production, water and nitrogen use efficiency is an important management goals. Drip irrigation is the most effective way to help improve water and fertilizer use efficiency. In this study, a two-year field experiment (2007 and 2008), the conditions of the water drip dosage and frequency of nitrogen on growth and nitrogen uptake of hybrid cotton explore the effect of hybrid cotton water and nitrogen fertilizer effect and the law of demand for the next film hybrid cotton under drip irrigation water and fertilizer management and efficient use of water and nutrient resources provide a theoretical basis. Hybrid Cotton (Biaoza A1) dry matter and nitrogen accumulation period of rapid growth at the beginning of flower - boll period, duration 40 days or so, the total absorption of nitrogen nutrient accounted for 60% to 65%; dry matter and Nitrogen accumulation rate in bloom around maximized. With the amount of nitrogen fertilizer or irrigation increased hybrid cotton dry matter and nitrogen accumulation period of rapid growth and delayed peak period, but the duration is similar to the maximum accumulation rate increases. Hybrid cotton dry matter and nitrogen accumulation and yield under water, nitrogen and their interaction was significant. In a certain range, hybrid cotton dry weight, nitrogen accumulation and yield with irrigation (360-520 mm) and nitrogen fertilizer (150-360 kg · hm ^{-2 ) increase increased significantly; however irrigation (600 mm) and nitrogen fertilizer (450 kg · hm ^{-2 ) is too large and does not promote hybrid cotton dry matter and nitrogen accumulation and increase production. Water, the amount of nitrogen fertilization and irrigation frequency significantly affect the dry weight of hybrid cotton, seed cotton yield and nitrogen accumulation. High irrigation frequency 0-40 cm soil moisture is conducive to remain at a high level, to promote the growth of hybrid cotton, a significant increase in the amount of nitrogen accumulation and seed production, improve irrigation water use efficiency. In nitrogen (360 kg · hm ^{-2 ) and low nitrogen (270 kg · hm ^{-2 ) levels, an increase in fertigation frequency can significantly promote the growth of hybrid cotton, increased dry matter and nitrogen accumulation; however large amount of nitrogen fertilizer (450 kg · hm ^{-2 ) when fertigation frequency has little effect on the growth of cotton. Therefore, in the critical period of hybrid cotton fertilizer, fertigation frequency appropriate awareness and promoting the growth of cotton, cotton production increased. In the present experimental conditions, the amount of hybrid cotton is suitable for irrigation 500-520 mm, nitrogen fertilizer is 300-360 kg · hm ^{-2 , hybrid cotton fertilizer critical period (after sowing 80-100d) irrigation fertilization frequency is kept at about 5 d.}}}}}}

Water and Nitrogen Response Characteristics of Hybrid Cotton under Drip Irrigation

Abstract

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