Digital citriculture : Soil fertility and plant nutrition

Digital citriculture addressing soil fertility and plant nutrition is nothing but reframing the 4R nutrient stewardship in a digitally retrievable version to address precise diagnosis of nutrient constraints and provide real time fertilizer recommendation through crop expert. In this direction, developing soil fertility variogram as decision support system and developing rationale of fertilizer use are the two important pillars digital citriculture. Customized fertilizers based on prevalence of nutrient constraints hold further a bigger promise for raising citrus crop. Thumping success in application of site specific nutrient management ( exploiting the spatio-temporal variability in soil fertility ) has aided a great deal in customizing the fertilizer demand in citrus. This success has paved to another success of tailoring the fertilizer requirement by adopting variable rate application of fertilizers through canopy growth -driven management zones. The application of mapped soil fertility variogram in spatial and temporal mode is still in infancy in other fruit crops, to tailor nutrient demand in a definite ratio, as a pre-requisite for specialty/customized fertilizers, with exception of crop like citrus. Authors through their long term studies succeeded in assembling the work done on these issues and putting it in a consolidated information to facilitate the development of digital citriculture backed up by customized fertilizers on scientific basis. However, these efforts would only meet an expected success, unless we develop a robust method of soil fertility evaluation with effective interpretation and tailoring nutrient requirement based on leaf analysis-mediated productivity-linked nutrient diagnostics. This is perhaps the maiden such massive effort towards developing a complete protocol for digital citriculture.