The term "Morse code" symptom is diagnostically associated with spongy tissue disorder in mango (Mangifera indica), particularly in the Alphonso cultivar. This disorder is characterized by the appearance of discrete, whitish, spongy patches within the mesocarp that remain unripe, even as the surrounding tissue matures. The affected tissue often forms irregular, discontinuous streaks or spots, resembling the dots and dashes of Morse code, making it a distinct diagnostic feature (Deshpande et al., 2011). The primary cause of spongy tissue is attributed to physiological and biochemical imbalances, particularly during the fruit development and ripening stages. Factors such as convective heat, uneven ripening, and altered enzymatic activities, especially of polygalacturonase and pectin methylesterase, contribute to the retention of unhydrolyzed starch within these regions (Chaudhary et al., 2013). Additionally, the disorder is exacerbated by pre-harvest climatic conditions, such as high temperatures and water stress, and is linked to impaired vascular function, which hinders proper nutrient and water translocation to certain mesocarp areas (Deshpande et al., 2011). Effective mitigation strategies include the selection of resistant varieties, optimized orchard microclimate management, and pre-harvest calcium and boron applications to improve cell wall integrity and metabolic function (Chaudhary et al., 2013; Deshpande et al., 2011). Thus, the Morse code pattern serves as a reliable visual cue for early detection of spongy tissue,

Arvind Kumar

The "Morse code" symptom, characterized by dark green streaks and dots along leaf veins, is a diagnostic symptom of Banana Bunchy Top Disease (BBTD), caused by the Banana Bunchy Top Virus (BBTV).

Thanks!