Advanced Search
Effects of Citric Acid on Phosphorus Availability for Soil in Greenhouse Field
Received:March 19, 2015  
View Full Text  View/Add Comment  Download reader
KeyWord:greenhouse;tomato;available phosphorus;citric acid;phosphate fertilizer
Author NameAffiliationE-mail
FANG Fu-li Institue of Environment and Sustainable Development in Agriculture, CAAS, Beijing 100081, China  
YAO Zhi-peng Institue of Environment and Sustainable Development in Agriculture, CAAS, Beijing 100081, China  
LIN Wei Institue of Environment and Sustainable Development in Agriculture, CAAS, Beijing 100081, China  
LI Yu-zhong Institue of Environment and Sustainable Development in Agriculture, CAAS, Beijing 100081, China
Environmental Stable Isotope Lab, CAAS, Beijing 100081, China 
liyuzhong@caas.cn 
XU Chun-ying Institue of Environment and Sustainable Development in Agriculture, CAAS, Beijing 100081, China  
LI Qiao-zhen Institue of Environment and Sustainable Development in Agriculture, CAAS, Beijing 100081, China  
Hits: 2802
Download times: 2664
Abstract:
      The utilization efficiency of phosphorus fertilizers in vegetable production under greenhouse condition is low in spite of its excessive use. Thus, it need to improve the availability of phosphorus and consequently reduce its application rate.In this study, a greenhouse trial was conducted to reveal the effects of citric acid on soil available phosphorus and tomato yield. Four phosphate fertilizer application rates(0, 96, 168, 240 kg·hm-2, denoted as P0, P1, P2, P3, respectively) and four citric acid levels(0, 0.42, 0.84, 1.26 kg·hm-2, denoted as CA0, CA1, CA2, CA3, respectively) were arranged with the method of completely random design. The results showed that soil pH decreased significantly(P<0.01) with the increment of citric acid addition level, and it decreased by 0.62 units for CA3P0 compared with CA0P0. Without the phosphate fertilization phosphorus release from the soil pool was enhanced in the top 0~20 cm soil after citric acid addition. However, as shown by treatment CA3P3, overuse of citric acid decreased the available phosphorus content in this soil layer, but increased the content in the 20~40 cm soil, which tend to leach to deep soil. The recommended application rates of citric acid and phosphate were 0.84 kg·hm-2(CA2) and 168 kg·hm-2(P2), respectively. This dosage not only produced a maximum tomato yield of 6.02 t·hm-2, but also reduced phosphate application by 30% compared with P3, implying a lower environmental risk of phosphorus leaching to the deep soil.