Balanced fertilization in fruit crops and modes of nutrient supply

Fruit crops by the virtue of extended juvenile period, long annual growth cycle and perennial woody framework are collectively known for their strong carbon sink regulating mobilization/immobilization of nutrients, thereby affecting the yield and fruit quality by ensuring thebiologically active rhizosphere. Balancing nutrients supply using popular methods comprising inorganic nutrition (soil application of macronutrients and foliar fertilization of micronutrients) as per crop phenology, site specific nutrient management (tailoring nutrient supply as per nutrients removal by fruits using spatial variability in soil fertility as decision support), fertigation (supply of irrigation and nutrients through their partitioning at growth stages using either surface or subsurface drip irrigation for reduced carbon, nutrient and water footprints), organic management (considering booth soil-plant health on an on-farm module basis) and integrated nutrients supply (inorganic nutrients-organic manures-microbes synergy having multi-tier nutrients release pattern to ensure extended nutrients bioavailability) are though in practice ,but witnessed periodical improvements with regard to production sustainability. All these nutrients supply modes are anchored through 4R nutrient stewardship principles, a pre-requisite for elevated nutrient-use-efficiency. Amid these scientific protocols of nutrient management, our understanding is still limited in effectively utilising the legacy nutrients stock of soil and introduction of crop nutrient holiday, if balanced fertilization is to be exercised with emphasis on production economics and nutrients fortification of fruits agronomically. Multiple objectives of balanced fertilization would only be fulfilled in fruit crops, unless a robust methods of diagnosis of nutrient constraints are developed with recurrent refinements to suit at regional agro-pedological conditions.