Mango Spongy Tissue or Soft Nose is a complex physiological disorder affecting mango crops’ productivity and profitability. Mango Spongy Tissue is a postharvest disorder that affects the internal quality of the fruit, resulting in the development of spongy tissue in the flesh of the mango. This disorder can cause significant economic losses for mango growers and exporters due to the reduced quality and marketability of the fruit. This makes the fruit unappealing to consumers, resulting in significant losses for growers and exporters.
It has been reported in many mango-growing regions, including Asia, Africa, Australia, and the Americas. Various methods have been proposed to prevent or reduce the incidence of mango spongy tissue disorder, including orchard management practices, preharvest and postharvest treatments, and genetic improvement of mango cultivars. Understanding the underlying causes of spongy tissue and developing effective management strategies are essential for sustaining mango production and ensuring the long-term viability of this important crop.
Mango Spongy Tissue and Black Tip Disorders Management
Characteristics of Mango Spongy Tissue Disorder
- The affected fruits are characterized by spongy, fibrous tissue in the flesh, often accompanied by off-flavors, low sugar content, and reduced nutritional value.
- It is the development of an inedible, sour, and yellow spongy patch in the mesocarp tissues of the fruit during ripening.
- The fruits have a bad odor and are not fit for consumption.
- The external appearance of the fruit is normal. The disorder can be identified only after cutting the fruit.
- It exclusively occurs in Alphonso mango varieties.
- It resembles bacterial rot symptoms in extreme conditions.
Causes of Mango Spongy Tissue Disorder Development
- The exact cause of MST is still unclear, but it is believed to be associated with various environmental factors, such as temperature, humidity, light, and water stress.
- The inactivation of ripening enzymes at the fruit maturation stage is due to high temperatures and convective heat.
- The exposure of the fruits to sunlight after harvesting will also develop spongy tissues.
- Over-application of nitrogen fertilizers.
- Fruits with low calcium content are also prone to this disorder.
Favorable Conditions of Mango Spongy Tissue Disorder
- The disorder is more prevalent in areas with high temperatures and humidity and is more common in late-maturing mango varieties.
- High temperatures above 30°C during fruit development and ripening can break down the fruit’s cell walls, leading to spongy tissue development.
- Excess moisture in the air can lead to water accumulation in the fruit, making it more susceptible to fungal and bacterial infections.
- Water stress during fruit development and ripening can reduce nutrient uptake and hinder cell division, resulting in the development of spongy tissue.
- Late-maturing mango varieties have a longer period to develop and are exposed to unfavorable environmental conditions for a longer time.
- Excessive use of nitrogen fertilizers can lead to the rapid growth of fruit, leading to reduced cell division and the development of spongy tissue.
Management Measures of Mango Spongy Tissue Disorder
- Harvest the fruits when they are 75% matured.
- Expose the fruits to low temperatures of 10-15°C for 12-18 hours after harvesting.
- Use windbreaks to protect the orchards from exposure to warm winds in May.
- Dip the fruits in calcium solution once or twice before harvesting to prevent calcium deficiency in the ripe fruits.
- Use sod culture and mulching techniques.
- Grow cover crops like legumes to reduce incidence.
- Spray Calcium fertilizers like calcium ammonium nitrate.
- Use Resistant varieties like Arka Puneet, Arka Aruna, and Ratna.