The hills raise mangoes the fastest
The common perception about mangoes is that they mature early in the country's north-western districts.
The Himalayan slope in the north sees more acute winters and summers than any other district, and this has fuelled the idea.
But a recent study proved a different theory.
The study found that the country's hilly terrain, which is closest to the sea, where there is less difference in temperature, ripens mangoes faster.
After the hills, the fastest rates of maturity were measured in Khulna, Rajshahi and Rangpur regions.
The study also shows that any variety of mango in the country's northern part takes at least three weeks more to mature when compared to the hilly regions' rate.
The study was published in the MDPI Sustainability journal of Switzerland on October 19.
It was jointly authored by Md Moniruzzaman and Khan Rubayet Rahaman of Saint Mary's University in Canada, Md Sorof Uddin of Bangladesh Agricultural Research Institute, Md Abdullah Elias Akhter of Khulna University of Engineering and Technology, and Akshar Tripathi of Indian Institute of Technology (IIT) in India.
The findings open up prospects for accurate planning and better management for cultivation, harvest, production, marketing and export of mangoes.
They would also help increase supply of different varieties of mangoes to meet the increasing demand, authors said.
The study divided the country's mango producing districts into four zones -- zone 1 (Chattogram, Cox's Bazar, Bandarban, Khagrachhari districts), zone 2 (Jashore, Satkhira, Jhenidah, Kustia, Chuadanga, and Khulna), zone 3 (Natore, Rajshahi and Chapainawabganj), and zone 4 (Naogaon, Rangpur, Dinajpur, Thakurgaon, and Panchagarh).
Data was collected between 2019 and 2020, using satellite-borne remote sensing technology, to study fruit maturity, harvesting time, and mapping locational differences.
The study explains, among other influences like soil moisture, rainfall, and temperature changes, that one degree latitude difference may result in two to five days' delay in mango harvest. Any mango variety in zone 4 will mature 20 to 22 days later than those in zone 1.
Analysis of past trends finds that mangoes from all over the country appear in the markets simultaneously, often resulting in deteriorated quality. Law enforcers destroy tonnes of mangoes for illegal ripening at the beginning of harvest season.
"Gobindabhog" is the country's earliest seen variety and it's usually grown in Khagrachhari and Bandarban districts, said Md Sorof Uddin, one of the authors.
"By cultivating this mango variety in the north, we can expand its supply easily," he said.
Popular mango varieties like Himsagar, Khirsapat and Langra stay around for two weeks. But this time period can be extended if these mangoes are cultivated in different regions with planning, authors said.
Bangladesh is among the Asian countries that contribute approximately 77 percent of the global share of mango production. Bangladeshi mangoes are finding markets in the USA, UK, Netherlands, and Canada.
Mango dominates the economy of the north-western districts of Bangladesh during the harvesting periods, engaging approximately 85 percent of people in mango-harvest related work.
The country has more than 500 different mango varieties.