AGRABLAST and AGRABURST TREATMENT OF COFFEE FUNGUS AND BLACK SIGATOKA ON BANANAS Coffee Leaf Rust is a major problem facing commercial coffee producers mainly in Africa, India, Southeast Asia, South America, and Central America. The causal agent of CLR is Hemileia vastatrix. CLR presents initially as small, roughly circular chlorotic lesions which spread in size as the pathogen infection spreads. As the disease progresses, necrotic regions (black, dead areas) develop within the lesions. Eventually, lesions grow in size to the point that some coalesce and, ultimately, the plant sacrifices the tissue through leaf drop. The sporulating fungus presents as yellow-orange and powdery, as shown in this photo: Many coffee plantations suffering from fungal coffee rust Hemileia vastatrix (also called Coffee La Roya) also are infected with Cercospora coffeicola (Berry blotch or brown eye spot) an opportunistic organism that targets already compromised plants meaning that both conditions often appear together. Cercospora coffeicola is also seen on coffee trees that are resistant to coffee rust. Current control of CLR is attempted through the use of partially resistant varieties or synthetic pesticides. The major coffee species grown commercially worldwide, Coffee arabica, is susceptible to H. vastatrix and efforts aimed at introgressing resistance from related Coffea species have not proven effective or durable. Synthetic fungicides are expensive and consistent use of copper-based products can lead to toxic accumulation in soils. GroGenesis offers two products for controlling plant pathogenic fungi, AgraBlast-1 and AgraBurst-2. These non-toxic, biodegradable, and relatively inexpensive products may provide an effective alternative to synthetic fungicides currently used for CLR control. GroGenesis products are anticipated to be effective at suppressing the spread of CLR in earlier staged infection events but it should be noted that they cannot 'cure' badly infected, necrotic leaves and return them to green, healthy states. Cost- effective and environmentally-friendly solutions to the CLR problem can restore economic prosperity to affected producer
communities and maintain coffee products at affordable prices worldwide. Several plantations in Guatemala were identified in July 2014 and sprayed using a 2 step regime of AgraBlast (initially 2 to 3 applications subsequently one application) followed by AgraBurst. This regime was repeated on 15-21 day cycles as necessary. Disease progression/regression can be measured easily (see appendix A) PRE TREATMENT Photograph 1 Photograph 2 Photographs (14/07/2014) Lesions can be seen on the leaves of the plant in photograph 1. In photograph 2 the leaf and spores can be more easily seen on underside of leaf plants were left untreated until a return visit on 21 st August when the progression of the disease was evident with more leaves scoring 4 & 5 than seen on previous occasion. Photograph 3 Photograph 4
Photograph 3. Blackening of leaf and die- back as infection spreads. Photograph 4. Necrosis and eventual leaf drop (score 5). The photographs below show examples of plants affected by both coffee rust and cherry blot a secondary infection which affect the surface of the leaves and results in premature ripening of the coffee beans which then turn black and rotten inside. Photograph 5 Photograph 6 The berry blot appears as brown lesions on the topside of the leaves, which then turn from green to yellow, then bright orange before eventually turning brown and resulting in necrosis and leaf drop. The berries (or beans) ripen prematurely resulting in the fruits turning black and rotten inside thus vastly reducing the yield. POST TREATMENT Photograph 7 Photograph 8
1 day after treatment with 1 spray. The difference in the appearance of the plants was apparent to the naked eye. On closer inspection with a magnifying glass, it was clear that the spores on the underside of the leaves were dead. With regard to the berry blight, the top of the leaves looked brighter and greener as seen in photographs 7 & 8 above. Further applications of AgraBlast improved efficiency of coverage necessary for long term control of disease. Photograph 9 Photograph 10 5 days after treatment. Photograph 9 shows plant affected with berry blot & coffee rust. As is evident in photograph 9, there are no signs of spores or fungus and the leaves are greener and brighter. Some plants were also showing signs of new growth. In photograph 10 the underside of the leaf shows no sign of spores and is drier. All treated areas sprayed with AgraBurst to facilitate recovery and remediation of the affected plants. Dr Helen Keenan who led the team stated When we saw the delighted response of the farm managers to the treated crops we knew we had something special. One plantation had tried more than 250 so called treatments, some that were extremely expensive and worryingly toxic for both workers and the environment. The evidence showed that the effect was immediate, no other product had achieved that. Many plantation owners wanted us to stay and treat all their farmland there and then, we are so pleased that we can help these people recover their economic assets without introducing dangerous chemicals. The AgraBlast and AgraBurst regime is truly an ecologically sound, inexpensive and sustainable solution Convinced that AgraBurst has helped plants recover and stimulate new healthy growth, plantations owners are eager to use the product as part of their overall management. AgraBurst mixes easily with other agricultural adjuvants meaning that it is easily incorporated into existing schedules without extra labour or equipment costs.
AgraBlast can also be used for the treatment of other fungal diseases, bacterial diseases and control of soft bodied pests. Previous trials with AgraBlast have found this product to be highly effective in the treatment and control of all the aforementioned. Photograph 11 Photograph 12 Photograph 11 - Workers spraying AgraBurst to plants previously treated with AgraBlast. Photograph 12 Young coffee plants also sprayed with AgraBurst to stimulate healthy growth, thus enabling the plants to strengthen natural defences and become more disease resistant.