【摘要】 为了探明湖南省柑橘园土壤硫素含量丰缺程度和柑橘施硫效应,2000~2004年开展了柑橘园土壤硫素含量调查与田间试验研究。结果表明,湖南省柑橘园0—20cm土层有效硫含量平均为47.7 mg/kg,低于临界值的占9.9%、潜在缺硫的占17.3%。随着土层加深,有效硫含量逐渐增加、全硫含量依次减少。土壤有效硫的地区分布,0—20 cm土层,81.3%的调查县中有10.0%~75.0%的柑橘园存在缺硫和潜在缺硫。柑橘叶片全硫含量平均为2.32 g/kg,有27.2%的柑橘园低于临界值。在有效硫含量不同的土壤中,柑橘连续4~5年施硫肥平均增产5.3%~30.0%,4个基点平均增产10.7%。连续施硫肥明显提高了柑橘叶片硫和氮含量,柑橘果皮中硫含量提高、氮含量降低,有利于果实品质的改善。施硫肥的增产优质效应表现为有效硫含量缺乏的土壤>潜在缺乏土壤>中等和丰富土壤;较长树龄>较短树龄。随着施硫肥年数延长,施硫增产优质效应更加明显。更多还原

【Abstract】 In order to investigate the status of soil S in citrus gardens in Hunan Province and citrus in response to S application,we carried out a survey of soil S in 81 citrus gardens,and conducted field experiments in 4 citrus gardens of Taoyuan county and Zhuzhou county of Hunan Province during 2000—2004.Results showed that for available S content at the surface 0—20 cm layer of citrus gardens soils,9.9% was lower than critical level,and 17.3% was potentially deficiency(average 47.7 mg/kg).Soil available S content increased gradually with increase in soil depth,whereas total S content decreased stepwise.Regarding the available S regional distribution,there were 10.0%—75.0% citrus gardens that soil available S in 0—20 cm soil layer was deficient or potentially deficient in 81.3% of all the investigated counties.The citrus garden in which total S content of citrus leaves was lower than critical value accounted for 27.2%(average 2.32 g/kg).Field experiments results showed that citrus yields increased by 5.3%—30.0% after continuous S fertilization for 4—5 years.Continuous S fertilization evidently enhanced S and N content in citrus leaves and S content in citrus fruit skin,reduced N content in citrus fruit skin,consequently improved quality of fruit.The order of yield and quality response to S fertilization was as follows: Available S deficient soil>available S latent deficient soil>available S medium and sufficient soil,and older tree-ages>younger tree-ages.With the years of S fertilizer application extending,the yield and quality response of S fertilization became more distinctively.更多还原