| Chestnut(Castanea mollissima Blume) belongs to China’s major grain woody species.but has the problems of high empty-shell ratio and low fruit quality of chestnut in production. Aiming at providing a scientific basis for the fertilization of chestnut, we chose chestnut cultivar’Yanhong’as experimental material to study the effects of boron on absorption of chestnut trees, physiological of Chestnut, fruit setting rate,and fruit quality in Tai’an, Shandong chestnut region. The study was carried out in field by the ways of, measuring photosynthesis and analyzing fruit quality among five levels of boron concentration. The main results were as follows:1. The study of absorption of chestnut trees in different parts showed that different organs could absorb boron. When4sprayed concentration of boron below0.4%, the content in the leaves was first increased and then decreased. After28days, the boron content in chestnut leaves reached its peak value of1.2ppm, which increased nearly six-fold comparing with CK and after the forty-fifth days the boron content of chestnut was stabilized. When sprayed concentrationof boron was0.5%, the boron content in leaves was1.8ppm, increasing nearly nine-fold than CK. After spraying5different concentration of boron, the content in flowers amounted to peak value of2.5ppm in the tenth day, increasing nearly four-fold than CK and the boron content was stabilized in fifteenth day. After spraying5different concentration of boron, its content in branches was first increased and then decreased with the peak value was0.9ppm increasing nearly three-fold than CK which appeared after the28days.2. Photosynthesis of chestnut by spraying different concentrations of boron fertilizer showed that5different concentrations had different effects on Chestnut photosynthesis. When concentration of sprayed boron was0.1%-0.4%, the leaf photosynthetic physiology improved When concentration of sprayed boron was0.3%, the effect was most significant with Chlorophyll content (Chl) was47mg-kg-1improving6mg-kg-1comparing with CK, photosynthetic rate (Pn) was18μmol CO2-m-2·s-1improving6μmol CO2·m-2·s-1comparing with CK, stomatal conductance (Gs) was195mol-m-2·s-1improved50mol-m-1·s-1comparing with CK, and intercellular carbon dioxide (Ci) was280μmol·mol-1improving80μmol·mol-1comparing with CK in the21days. But photosynthetic physiology have no significantly resonses to boron when it reached to0.5%in leaves.3. Fruit Setting Rate and fruit individual form in chestnut maturity period and measurement of fruit quality suggested that spraying5different concentrations of boron fertilizer had obvious effects on Fruit Setting Rate, and significantly improved the chestnut production at0.3%concentration which was71.3%up to2.5times of CK. Analysis of fruit quality results for5different concentrations of boron showed that Chestnut fruit quality had certainly improved. When concentration of sprayed boron was0.2%, starch content increased8%than CK. When concentration of sprayed boron was0.3%, Chestnut fruit color was more bright, soluble sugar content increased8%and Single single grain weight increased2g than CK. From the measurement of fruit quality, it was improved overall when the boron concentration was0.2%or0.3%. |
