Easily Extractable Glomalin-Related Soil Protein as Foliar Spray Improves Nutritional Qualities of Late Ripening Sweet Oranges

The role of arbuscular mycorrhizal fungi in sweet oranges is well known, but the function their secondary metabolite, especially easily extractable glomalin-related soil protein (EE-GRSP), an active fraction glomalin, still unclear. proposed study aimed to analyze field response foliar application exogenous EE-GRSP on tree development and fruit quality two orange (Citrus sinensis L. Osbeck) varieties viz., Lane Late Navel (LLN) Rohde Red Valencia (RRV). Application significantly increased root colonization hyphal length both varieties. external fruits (fruit weight, polar diameter, equatorial diameter) also improved However, treatment showed no change soluble solid content, while it Vc solids-acid ratio, fructose, glucose, sucrose content sarcocarp LLN variety treated with recorded higher N, P, K, Fe, Si as a mark nutritional quality, RRV displayed concentration nutrients like Cu, Si, Zn compared corresponding non-treated control. To best our knowledge, this first report regarding improvement late-ripening (especially LLN) another potential biostimulant.