Investigations on the control of fruit drop in alphonso mango

Field experiments were conducted during 1998–2002 for identification of pollinizer varieties, control of recurring flowering and control of fruit drop by use of mineral nutrients and growth regulators in Alphonso mango at the Regional Fruit Research Station, Vengurle, Sindhudurg. The investigations revealed that variety Kesar, Ratna and Goamankur were the best pollinizer varieties for Alphonso mango as substantiated by synchrony in flowering with Alphonso, better fruit set and acceptable fruit quality of pollinizer. Alphonso x Alphonso cross combination showed only 4% fruit retention whereas, Alphonso x Kesar, Alphonso x Ratna and Alphonso x Goamankur revealed 10–12% fruit retention. Therefore, plantation of 10 to 15% trees of Kesar, Ratna or Goamankur in Alphonso orchards as pollinizers was recommended. The recurring flowering emerging at the base of old flowering panicle causes heavy fruit drop from adjacent old ones. The foliar spray of GA₃ (50 ppm) at full bloom stage significantly reduced the recurring flowering in Alphonso mango. For control of flower/fruit drop in Alphonso mango, foliar spray of nutrients (urea, KNO₃, micronutrient complex) and growth regulators (NAA, triacontanol) at different concentrations were tested separately and in combination. The three years data revealed that urea 2%, NAA 20 ppm and micronutrient mixture 50 ppm in combination produced significantly higher fruit yield followed by combined application of urea + triacontanol + micronutrient.