In Sindh thousands of shisham trees (Dalbergia sisso) are encountering an unknown disease the 'sudden death' since last 10 years. These trees are planted along the canal sides and on irrigated plantation areas which come under the control of Sindh Forest Department.

The most affected areas are in district Khairpur, Sukkur, Ghotki, and part of Naushero Feroze and Nawabshah. The menace, for want of remedial measures, is gradually wiping out this natural wealth and the decades-old landscape in various parts of Sindh and Punjab.

Reportedly, the same disease is causing devastation to shisham trees in India, Nepal and Bangladesh. According to the Punjab Forest Department, at least 30,000 such trees have been afflicted by it, causing colossal loss to the government and to farming community.

To save these trees, many seminars and workshops have been held. The research institutes too, are trying to chalk out a strategy to control this disease, but all in vain.

The UN's Food and Agriculture Organization (FAO) has provided $0.236 million for a regional project to arrest the rapid spread of the disease in Bangladesh, India, Nepal and Pakistan. Unfortunately, even after four years, nothing positive has been heard from any country with the disease gradually moving on.

The Punjab government too, has approved a five-year project at a cost of Rs18.595 million to undertake field research which is being executed by the Punjab Forest Research Institute.

The same disease is found to be causing damage to mango trees, in Sindh and Punjab. Growers have complained that suddenly their full grown trees have fallen victim to it. The disease hits the leaves, shoots, branches, and roots, eventually bringing death to whole tree.

A study by the Mango Research Station Shujabad found that the trees die within a few days of the appearance of a black foul-smelling fluid at the collar portion of stem. The degradation of cells in collar region blocks the movement of water and nutrients, causing death of roots and branches. Infected roots are considered the main cause of the disease.

After wreaking mango orchards and shisham trees, the disease has now moved on to guava orchards in Larkana. Larkana is known for producing the best varieties, including seedless guavas. Moreover, orchards spreading over on hundreds of acres in Naudero-Mahota have created a beautiful landscape, also in rice growing area.

The survey of infected orchards in Larkana undertaken by this writer indicates that presently the menace is restricted to some localized pockets affecting not more than 20 to 30 trees.

However, if the organism is same then the fate of guava orchard would not be different from that of mango and shisham. Neither, the Horticultural Research Institute of Sindh, nor Parc has come to the rescue of growers.

A British journal the "New Scientist" June, 2004 issue says that history has shown that importing exotic patheges to the places where plants have no resistance can spell disaster".

Another disaster is the "sudden oak death", a disease caused by a fungus called phytopthora ramorum. Native to Asia, this micro-organism slipped into the US and Europe on ornamental plants.

In California, the disease has became epidemic in wild woodlands before anyone knew about the existence of the fungus. Now it is killing trees in the UK and the Netherlands. If efforts to contain the infection fail, it could do untold damage to forests world wide."

Every serious epidemic of plant disease, from potato blight, Dutch elm disease, to Banana bunch-top-virus and now the sudden oak death are result of the movement of infected plants or timber around the world.