Micronutrients spray to combat granulation and improve fruit quality of sweet orange [Citrus sinensis (L.) Osbeck] cv. Mosambi under nontraditional citrus growing track

Abstract

Calcareous and alkaline soil is the major drawback for low yield and poor fruit quality of sweet orange cv. Mosambi with increased granulation problem because such types of soil hinders the smooth micronutrient uptake from the soil. Therefore, the impact of micronutrients spray for three times at one month intervals from May to July on granulation and fruit quality of Mosambi was initiated for two consecutive years (2018–19 and 2019–20). Combined application of Zn @0.5% + Fe @0.2% + B @0.3% + Cu @0.1% followed by B @0.3% + Fe @0.2% and Zn @0.5% + B @0.3% were found effective for improving growth of Mosambi plants. Yield was also obtained maximum in foliar spray of Zn @0.5% + Fe @0.2% + B @0.3% + Cu @0.1% (19.92 t ha−1). Maximum fruit weight and volume was obtained in B @0.3% + Fe @0.2% treatment (173.80 g and 190.53 cc, respectively). Fruit quality attributes in terms of total soluble solids (TSS): acid ratio, sugar, and phenol content were recorded maximum in Zn @0.5% + Fe @0.2% + B @0.3% + Cu @0.1% spray. Minimum incidence of granulation was observed in Cu @0.1% spray (1.96%) with par result in Zn @0.5% + Fe @ 0.2% + B @0.3% + Cu @0.1% (2.33%). Hence, it can be concluded that three foliar spray of Zn @0.5% + Fe @0.2% + B @0.3% + Cu @0.1% from May to July is very effective to get maximum yield of better quality, granulation free fruits from Mosambi orchard under non-conventional citrus growing track having calcareous and alkaline nature of soil.