Research On Different Fertilizers Applied To Cotton Under Drip Irrigation Condition

[Object] Fertilization is an important measure for increasing crop product and efficiency.The types and characteristics of fertilizer is one of the main bases for rational fertilization.The objective of this study is to (1) determine effects of different fertilizers on growth, yield,and fertilizer use efficiency of cotton under drip irrigation,(2) provide reference for fertilizerselection and rational application in drip-irrigated cotton field.[Methods] The traditional chemical fertilizer, drip-irrigation specific fertilizer,phosphate-solubilizing fungus fertilizer and organic fertilizer were used in this study. Threefield experiments including drip-irrigation specific fertilizer experiment,phosphate-solubilizing fungus fertilizer experiment and organic fertilizer experiment wereconducted at an agricultural experimental station at Shihezi University from2012to2013.Four fertigation methods were set as traditional chemical fertilizer basal application (CK),traditional chemical fertilizer topdressing (DCK), ordinary drip-irrigation specific fertilizer(F1N), and high phosphorus and potassium fertilizer for drip-irrigation (F2N) in dripirrigation specific fertilizer experiment. The experiment of phosphate-solubilizing fungusfertilizer set three treatments as traditional chemical fertilizer (CK), traditional chemicalfertilizer+phosphate-solubilizing fungus fertilizer once application (PPF1), and traditionalchemical fertilizer+phosphate-solubilizing fungus fertilizer five applications (PPF2). Theorganic fertilizer experiment included chemical fertilizer basal application (CF1), chemicalfertilizer topdressing (CF2), and organic fertilizer basal application+chemical fertilizertopdressing (OF) treatments.[Results](1) Under the equal nutrient input conditions, the highest yield of cotton was found inF2N treatment, and then was in F1N and DCK treatment, CK had the lowest yield. Therewere no significant differences for N use efficiency of cotton among F2N, F1N and DCKtreatments, but those were significantly higher than CK. Phosphorus uptake of cotton plant inF2N, F1N and DCK treatments were significantly higher than that in CK treatment. Effects ofdifferent fertigation methods on N use efficiency of cotton were similar with cotton yield.(2) Under the equal fertilization cost conditions, nutrient uptake and yield of cotton inDCK treatment were significantly higher than those in F2N, F1N, and CK treatments. Nosignificant differences were found for dry matter weight, P uptake, and yield of cotton amongF2N, F1N, and CK treatments. N uptake in F2N and F1N treatments were significantly lowerthan that in CK treatment, but K uptake were lower than CK.(3) Combination of phosphate-solubilizing fungus fertilizer and chemical fertilizersignificantly increased dry matter weight, nutrient uptake, and yield of cotton. Cotton yield inPPF1and PPF2treatments were13.32%and19.73%higher than CK treatment, respectively.Dry matter weight and nutrient uptake of cotton plant in PPF1treatment were significantlyhigher than those in PPF2treatment. The yield of cotton was5.66%higher in PPF1treatmentthan in PPF2treatment. (4) The OF treatment had the highest dry matter weight, yield and N use efficiency, andthen was CF2treatment, CF1treatment was the lowest. Cotton yield of the OF treatment were11.51%and20.61%higher than that of CF2and CF1treatments, respectively. N useefficiency in the OF treatment were16.82%and20.95%higher than that in CF2and CF1treatments, respectively. P use efficiency in OF and CF2treatments were11.15%and7.76%higher than that in CF1treatment, but no significant difference was found between OF andCF2treatments.[Conclusion](1) Drip-irrigation specific fertilizer can increase cotton yield and fertilizer use efficiency,especially for high phosphorus and potassium fertilizer. However, under the equal fertilizercost conditions, there were no significances between drip-irrigation specific fertilizer andtraditional chemical fertilizer basal application, even less than traditional chemical fertilizertopdressing. Therefore, decreasing the application costs of drip-irrigation specific fertilizer isan important issue.(2) phosphate-solubilizing fungus fertilizer application can significantlyincrease nutrient uptake and yield of cotton, and phosphate-solubilizing fungus fertilizer onceapplication also is better than phosphate-solubilizing fungus fertilizer five applications.(3)Combination organic fertilizer and chemical fertilizer can improve cotton yield and N useefficiency, but has no significant different with chemical fertilizer topdressing in P useefficiency.