ISLAMABAD, May 20: The ministry of food, agriculture and livestock (Minfal) has requested the Australian government to send experts to detect the causes of an unknown disease called Sudden Death, which has destroyed 10 per cent of mango trees in Punjab and Sindh and a large number of Sheeshum-timber countrywide, sources told Dawn on Thursday.

The Australian High Commission had asked Minfal and the ministry of industries and production to dispatch the pictures of disease-stricken trees and other relevant data so that they could send an appropriate team of experts, the sources said.

Pakistani mango trees have been encountering seven major diseases — Powdery Mildew, Anthracnose, Sooty Mould, Bacterial Leaf Spot, Root Rot, Mango Malformation and Sudden Death or Die Back. However, the reasons behind the last two diseases are still not confirmed.

When contacted the commissioner (minor crops), Minfal, Dr Mohammad Aslam Gill, said that in recent years, besides other diseases, Sudden Death had attacked mangoes in Punjab and Sindh. In this disease pathogen attacked the collar region of the main trunk and roots. Infected bark at the collar region as well as the roots turned brown and rotten. If bark of the infected plant is removed in collar region with a knife, slimy liquid oozed out.

In many cases healthy looking plants showed sudden wilt symptoms in two to three days, he said. The infected plants also showed symptoms of gummosis. All the leaves remained attached to the twigs even after wilting, but in some cases some of the leaves in canopy fall down and the canopy became thin.

Mr Gill said in some cases one or two branches dried up. With the advancement of the disease, the pathogen girdled the whole trunk of the tree and caused sudden death of the whole plant. The diseases appeared and spread more quickly in the neglected-than-properly-maintained gardens, he said.

He said scientists had suspected the role of insects associated with the problem, as they had observed the presence of large population of Bark Beetle on the trunk of infected trees in Sindh. However, the attack of Bark Beetle was not severe in Punjab although it was present.

Scientists believed that intercropping was a common feature which necessitated the use of farm machinery causing injury to plants and enabled the fungus to enter the plants through that damaged parts, he said.

According to official statistics, in 2003-04 mango trees were spread over an area of 54,300 hectares in Punjab and 47,100 hectares in Sindh and the provinces produced 707,800 tons and 338,400, respectively. They show that only five districts of Multan, Vehari, Muzaffargarh, Bahawalpur and Rahim Yar Khan produced about 75pc of the total mango production of Punjab. In Sindh, mango is largely grown in Mirpur Khas and Hyderabad districts. The attack of the Sudden Death disease is severe in these areas and if not controlled could damage the production and ultimately the export of the fruit.

Pakistan’s mango export share in the world market is 3.2 per cent and 85 per cent of its export is to Dubai. Mango spread over an area of 94,100 hectares in 1999-2000, which increased to 103,100 hectares in 2003-04. Likewise, its production has increased from 937,700 tons in 1999-2000 to 1.056 million tons.

However, there was no significant increase in the yield which remained hovering around 12 tons per hectare in 2004. When contacted additional secretary, Minfal, Mumtaz Shaikh, told Dawn that teams comprising experts of the Pakistan Agriculture Research Council had been sent to the affected areas. He said the ministry had also provided Rs10 million to the experts to detect the causes of disease and come up with a plan to counter the attack.