Effects of organic fertilizer on water use, photosynthetic characteristics, and fruit quality of pear jujube in northern Shaanxi

Abstract

This experiment is based on the 7-year-old dwarf and densely planted pear jujube in northern Shaanxi. The effects of applying organic fertilizer on water use, photosynthetic characteristics, and fruit quality of pear jujube are studied. The test has been carried out for two consecutive years. The results showed that fertilization treatments could promote soil moisture retention and utilization. Compared with the control (CK) in 2011, the average soil water content (SWC) of soybean cake fertilizer (SC) and sheep manure (SM) increased by 3.69 and 3.18 percentage points, respectively. The effect of SC on chlorophyll content was most significant. Fertilization can effectively improve the canopy structure of pear jujube. The transmittance of SC and SM decreased by 20.20% and 17.38%, respectively, in 2012. The gap scores were opposite to the leaf area index (LAI). Continuous application of organic fertilizer can significantly increase the net photosynthetic rate and stomatal conductance of pear jujube. The instantaneous water use efficiency of chemical fertilizer (CF), SC, SM, and biogas fertilizer (BM) increased by 0.44, 1.33, 0.96, and 0.61 percentage points, respectively. Organic fertilizer effectively increased the fruit setting rate, yield, and quality of fruits. After fertilization for two consecutive years, the quality of pear jujube fruit improved significantly. It indicated that long-term fertilization could effectively promote the growth and development, increase yield, and significantly improve the fruit quality of pear jujube in the loess hilly region of northern Shaanxi. The effect of soybean cake fertilizer was the most significant.