Black Stigatoka Disease

                Black Sigatoka is a leaf spot disease of banana plants caused by ascomycete fungus Mycosphaerella fijiensis (Morelet). Plants with leaves damaged by the disease may have up to 50% lower yield of fruit. Black Sigatoka, also known as black leaf streak, was discovered in 1963 and named for its similarities with the Yellow Sigatoka, which is caused by Mycosphaerella musicola (Mulder. Black Sigatoka is a fungal disease that destroys banana leaves and can seriously reduce crop yield. It is very severe on Cavendish bananas, ladyfingers and several other dessert bananas.

 

Impact of banana diseases

A leaf spot disease is the most important of these problems. Black Sigatoka, which is also known as black leaf streak, causes significant reductions in leaf area, yield losses of 50% or more, and premature ripening, a serious defect in exported fruits. The islands of St Vincent and the Grenadines is in the process of eradicating the Black Stigatoka disease which has badly affected banana farms on the island. The economy of St Vincent and the Grenadines is based largely on agriculture, which contributed 10% of the GDP and 26% of the labour force. Banana one of there main crop, although its importance has declined significantly as more focus is being placed on roots and tubers, has seen further decline in the country as farmers are abondoning their crops as a result of the disease.

 

Control

Presently, a sterol biosynthesis inhibitor, tridemorph, several different sterol demethylation inhibitors, most importantly propiconazole, and the methoxyacrylate, azoxystrobin, are the most commonly used systemics.

Orchid Blossom Midge

Today on my first field trip in Barbados I learned about a new disease called the Orchid Blossom Midge, it is a recently arrived pest to orchid growers. I have found some information in regards to the disease that I would like to share with my readers.

The orchid blossom midge is a member of the gall midge family (Cecidomyidae), so named for the galls that form in plants attacked by some species during their larval stage. The orchid blossom midge is polyphagous (feeds on many types of plants) and will attack orchid buds and flowers. This can cause bud blast, as well as damage and deformity to the developing floral tissues. Because the midge larvae flourish in conditions with high humidity and require a damp medium in which to pupate, they thrive under conditions ideal for growing orchids.

Life Cycle - The small, flying adult midges lay large quantities of eggs in flower buds. The eggs and developing larvae are virtually undetectable inside the closed bud, until the damage from the feeding larvae becomes evident - Midge larvae are small (approximately 7/64–1/8 inch [2.5–3 mm] in length), white, and resemble fungus-gnat larvae in appearance. At maturity, larvae jump from the plant to the surface of the potting medium by curling and uncurling their bodies in a springlike fashion for propulsion. They then burrow into the top layer of the medium to pupate. The tiny adult flies emerge about three weeks later. Symptoms Evidence of possible orchid blossom midge infestation includes bud blast, brownish spots that appear chewed, holes in buds and floral tissues, and fungal infections that may follow in areas damaged by the midges. The midge larva is most prevalent in temperate areas and can be identified by their presence inside unopened flower buds. Under favorable conditions, this pest can become entrenched within 14 days. A serious infestation can be devastating, rapidly destroying an entire flowering if left unchecked Controls - Remove all damaged, molding or dropped buds. Eradicate weeds in the growing area, as well as in and around plants - Applications of pesticide may be useful, such as Diazinon granules to the medium to eradicate burrowing larvae and Orthene (used with a penetrant such as LI 700) to foliage and buds to control egg-laying adults and larvae. - Biological controls, such as Hymenopteran predatory wasps, have proven effective against other gall midge species, and may be useful for C. maculipennis as well.

What can Integrated Pest Management (IPM) do for you?

 

 Are pests ruining your plants, causing you to experience major lost and reducing the final quality of your product?  Well I have a method for you that can be used on both organic and fertilized crops; Integrated Pest Management control system is the best method for you.

 

Integrated Pest Management (IPM) is an environmentally sensitive and effective pest management system. Through this system farmers can inspect their crops over periods of time to evaluate the damage done to their crops and assess whether the crops may require pesticides or local remedy (control method). IPM is not a single control method but, rather, a series of pest management solutions. This method allows the farmer to make the choice of using pesticides or placing preventative methods to reverse that damages that have occurred. 

The steps to be followed are:-

1. Set Action Threshold - before using pesticides look into the situation to know if pesticides are needed.

2. Monitor & Identify Pests - each pest needs to be monitored to be treated properly, this allows the farmer to know whether pesticides will be needed

3. Prevention - place preventative measures to ensure  that chemicals does not cause harmful effects to your crops. 

4. Control - select control methods to ensure that your plants are not affected by reoccurring pest or that the chemicals does not have harmful effects on the plants in the long run.