Comprehensive Analysis Of Soil Characteristics And Quality Of Camellia Oleifera In Typical Planting Areas Of Guizhou Province

China has a history of camellia oleifera cultivation for more than2300 years.The problems of low yield,uneven quality of camellia oleifera oil and low economic benefit are still the important factors that restrict the development of camellia oleifera industry.The study on soil fertility and quality of Camellia oleifera forest was carried out,and the suitable soil nutrient conditions in Camellia oleifera growing areas were screened to help the high-quality development of Camellia oleifera industry in Guizhou province,therefore,scientific and rational fertilization is an important way to increase production and income of Camellia oleifera industry.In this study,we selected the towns of Bijiang District(BJ),Tongshan(TS),Zhujiachang(ZHJ)and Pingxi(PX)in the Yuping Dong Autonomous County of Shiqian County,Tongren Province The Qiandongnan Miao and Dong Autonomous Prefecture towns of Lantian(LT),Fengcheng,Lianjiang County(FC),Maoping,Hubei(MP),Tam Giang(SJ),Liping County(DF),Gaotun(GT),YD(YD),Yong Li(YL)and Dou Li(DL)in Congjiang County;Qianxi’Nan Buyei and Miao Autonomous Prefecture Zhl(Zhl),Shuangjiang,Changsha County(Shj),Wangmu village(WM)and SHT(SHT)in Wangmo County,and GJ and LS(LS)in Longli County Qiannan Buyei and Miao Autonomous Prefecture,soil,Camellia oleifera fruit and camellia oil from 20 typical camellia oleifera growing areas in Yupingjie(YP),Libo County Province were studied and determined,the present situation of soil quality in various planting areas was studied by means of mathematical analysis methods such as diversity analysis,principal component analysis,canonical correspondence analysis and redundancy analysis The differences of economic characters and quality of Camellia oleifera fruit in different planting areas were compared,and the quality of Camellia oleifera oil in different planting areas was comprehensively evaluated,it provides theoretical reference for rational fertilization,scientific development and Camellia oleifera management.The main results are as follows: soil quality and key factors in different planting areas were studied.Ten soil physical and chemical indexes were selected to evaluate the soil quality in different planting areas.The results were as follows: soil organic matter,soil pH,total potassium,hydrolyzed nitrogen and available phosphorus were entered into the minimum data set(MSD),the comprehensive scores of soil quality of Camellia oleifera plantation in different planting areas were SHT > PX > WM > ZHJ > Zl > SHJ >LT > MP > FC > SJ > YP > TS > YL > DF > DL > YD > GT > GJ > BJ >LS.(1)The economic characters of Camellia oleifera fruitThe results showed that the fruit of camellia oleifera in LS area was small,while that in WM and PX area was relatively large,fruit shape index was negatively correlated with fruit weight,single fresh seed weight,fresh kernel weight and other indexes related to fruit weight.It is suggested that the ratio of fruit height to fruit diameter should not be too large,and the appearance of orange or spherical fruit is one of the most suitable characters for selecting superior trees.The oil content of dry kernel was positively correlated with fruit weight,dry seed weight and dry kernel weight.Therefore,the fruit quality could be inferred from the appearance of the fruit.(2)The quality of camellia oilThe results showed that the average relative contents of oleic acid,palmitic acid and linoleic acid were 78.91%,14.62% and 4.44%,respectively,the average relative content of stearic acid was 2.03%,the average content of squalene was 171.7 mg/kg,the average content of vitamin E was 162.43 mg/kg,the average content of phytosterol was263.43 mg/kg,the average content of total flavonoids was 5.59 mg/kg,the average content of total polyphenols was 120.73 mg/kg,the average peroxide value was 0.83 mmol/kg,the average acid value was0.83(Koh)/(mg/g),the average iodine value was 84.72 mg/100 g.The comprehensive scores of tea oil quality in different planting areas were as follows: DF > WM > SHT > FC > SJ > YD > LT > ZHJ > PX > GT >YL > SHJ > MP > DL > BJ > GJ > LS > ZL > YP > TS.(3)Key factors of soil in different planting areasSoil organic matter,soil pH,soil total nitrogen and soil bulk density were the key factors affecting and restricting the economic characters and quality of Camellia oleifera fruit.In order to improve the soil quality,the areas with high potential of camellia oleifera industry should pay attention to the rational control of nutrient allocation and balanced fertilization,and the areas with low ranking should pay attention to increase the total amount of fertilization,to lay a good soil foundation for planting Camellia oleifera.