March 5, 2010
Managing the Black Sigatoka Leafspot disease


A LEAF infected with black sigatoka shows a series of black streaking on the underside of the leaf which eventually kills the entire leaf and the tree in quick succession.

“500 acres to be rehabilitated and 155 acres to be replanted.”{{more}}

Those are but some of the targets set for the newly established Banana Services Division (BSD) in the Ministry of Agriculture, established on the closure of the Banana Growers Association. Along with having total responsibility for the production of banana and certification of farmers, this Division has the added task of implementing as astute Management and control program for the dreaded Black Sigatoka leafspot disease.

According to Sylvester Vanloo, head of the 11-member strong team of officers, the BSD has a major challenge ahead that can only be surmounted with the assistance of the farmers involved and other players concerned with the production of bananas.

In 2007, the bacterial wilt, Moko Disease, made a landfall in SVG and immediately a Control and Management program was executed. This involved an extensive spraying and elimination of infected fields, compensation to farmers and an educational program. In addition, infected areas had to be fallowed for no less than 18 months, followed by the necessary research activities to determine whether the infected areas were rid of the bacterial.

Two years later in December of 2009, the Black Sigatoka became a major issue. It was originally observed on the windward coast, (Langley Park, Perseverance, Grand Sable and Lot 14). However, today it has extended island wide to include the major banana producing areas of Greiggs, Byrea, South Rivers, Park Hill, Colonarie, Diamonds and those on the leeward side. This is two months after the declaration in December and the implementation of another management and control program that is systematically being coordinated through the BSD, the Plant Protection and Quarantine Unit and the Extension and Advisory Services in the Agriculture Department.

This program involves initial scouting of the banana producing area for the disease supported by reports made by farmers of suspicious cases. Immediately, on verification, the area is sprayed by a patrolling ground crew supported by aerial spraying. In addition, farmers are involved in a training and awareness program that involves a series of workshops. In these sessions, farmers are given instructions regarding identification of the signs and symptoms of the Black Sigatoka and the necessary management practices they ought to carry out in the banana fields to reduce the intensity and effects of the disease.

So far, Vanloo has identified the following management practices as crucial to control of the disease – adhering to the recommended fertilizer applications, nematode and borer control, detrashing and deleafing which emphasizes placement of the trash across the contours with the leaf midrib facing down; maintaining a weed-free field and the removal of harvested plants to reduce overcrowding of the fields, hence, the humidity within the field.

‘We have been very blessed with the proliferation of the current dry period as this has assisted in suppressing the spread of the fungus. However, the high winds have done its portion in spreading the disease, but we are also implementing a vigorous ground spraying exercise that is taking care of this. Currently, we are pleased with the levels of control attained, in that fields sprayed rarely show a reoccurrence of the effects of the Black Sigatoka, especially if the farmer institutes proper field sanitation practices.

Although the disease can be controlled and managed, it is not easily eliminated and thus the control of the Black Sigatoka has been absorbed into the regular leafspot disease control program, a critical component for banana production.

If we are able to continue the current trend of identification, reporting, and treatment, complimented by the farmers executing proper field sanitation and production practices, then we can safely say that the replanting and rehabilitation efforts for this year will be successful. We expect another consignment of about 100,000 banana plantlets of the Jaffa variety from Israel. From all indications, this has been a very good performer, giving at least 1? to as much as twice times the current yields under favourable condition with good production practices. This is good indications for the banana industry as far as production is concerned and we stand in readiness for the onset of the rains which may bring with it added challenges.