Effect Of Tillage And Integrated Nutrient Management Models On Tea Growth,Quality,Nutrients Utilization And Soil Properties

In recent years,tea consumption was high due to increasing in population.So the demand of green tea is high,in order to meet the demand we need to improved tea yield by different strategies.Integrated nutrient management and tillage are important factors influencing tea yield and quality.Optimizing these factors can help improve soil physical properties,tea quality and yield.A 2-yr field study was conducted to determine the effects of different tillage and integrated nutrient management models(zero tillage with no fertilizers(CK);shallow tillage with mineral fertilizers(ST+NPK);deep tillage with mineral fertilizers(DT+NPK);deep tillage with mineral fertilizers and rapeseed cake manure(DT+NPK+RC);deep tillage with mineral fertilizers and biochar(DT+NPK+B)on soil physical properties,chlorophyll content,tea quality and yield.Tillage and integrated nutrient management models had significant effect on soil physical properties,chlorophyll content,tea quality and dry biomass.DT+NPK+RC model increased porosity,soil water content but decreased soil bulk density(BD)and penetration resistance(PR)as compared to CK,followed by DT+NPK+B.The soil water content decreased while PR and BD increased with soil depth.DT decreased BD and PR and increased porosity,soil water content as compared to ZT and ST.DT+NPK+RC and DT+NPK+B treatments had the highest water stable macro-aggregates(>250μm),while the percentage of micro-aggregates(<250 μm)was lowest in DT+NPK and ST+NPK.In2020 and 2021 Chlorophyll contents,tea quality and yield,partial factor productivity(PFP)and apparent recovery efficiency(ARE)were significantly increased in DT+NPK+RC model as compared with CK model,followed by DT+NPK+B model.Chlorophyll a/b ratio was not significantly affected by tillage and integrated fertilizers models.Soil physical properties had a significant correlation with chlorophyll contents,PFP,ARE,quality and yield of tea.Organic-based fertilizers have been proven to be effective in improving soil fertility and plant growth.The tea root system plays a key role in the uptake of nutrients and water from the soil.However,the effects of integrated fertilization on growth,quality of tea and soil physiochemical properties in tea orchard soil are unclear.The effect of integrated fertilizers(Control(CK),100%NPK,100% NPK with biochar(NPK+B),50% NPK with 50% rapeseed cake(NPK+RC),and 100%rapeseed cake(RC))on alterations in soil physiochemical properties,root growth characteristics,nutrient uptake,NUE,and biomass production and quality of tea was studied in the greenhouse of the China Tea Research Institute,Chinese Academy of Agricultural Sciences,Hangzhou,during2020–2021.The results showed that NPK+RC resulted in significant(p< 0.05)reductions in soil penetration resistance and bulk density and improvement in porosity compared to control.NPK+RC recorded significantly higher(P< 0.05)root surface area,root volume,root tips,root length,and root CEC of tea than NPK and control.The combined application of RC and NPK fertilizer significantly decreased the specific root surface area and specific root length compared to the control.Root,stem,leaves,and total biomass were improved by integrated fertilization compared to the control and mineral fertilization.The nutrient content(N,P,K),nutrient uptake,NUE,nutrient uptake per root length,volume,and surface area of tea plants under NPK+RC and NPK+B were significantly(P<0.05)higher than RC and CK.The results also indicated that NPK+RC and NPK+B significantly improved the different amino acid and catechin concentrations in the young shoot,stem,and root of tea as compared to CK.The plant growth parameters,e.g.,plant height,no.of leaves,stem mid girth,and fresh weight of stem and leaves,were significantly increased by integrated fertilization as compared to CK and solo organic and inorganic fertilizers.Chlorophyll content(Chl a,Chl b and Chl a+b)were generally higher with NPK+RC than CK,RC,and NPK treatments.Integrated fertilization buffered the acidic soil of the tea garden and decreased the soil C:N ratio.NPK+RC also significantly increased the soil total C,N,P,and available P,K,nitrate and ammonium concentration as compared to CK and RC.The soil macro and micronutrients(Ca,Mg,Fe,Mn,Cu,and Zn)were significantly improved by RC and NPK+RC as compared to CK.The chlorophyll contents,soil macro and micro nutrients were all significantly positively correlated with tea quality and growth.These results indicated that deep tillage with integrated nutrient management models should be practiced in tea plantations to improved soil physical environment,soil nutrient status,root growth,nutrient uptake,which were associated with the improvements in NUE,tea growth,tea quality and yield through the efficient exploitation of nutrients.Thus,DT+NPK+RC is feasible for the improvements of soil physicochemical properties,root growth,tea quality and yield.