BioAct®WG Promotes Root Development, Increases Yield of Banana
In the course of finding alternative control measures, a team of Filipino nematologists led by Dr. Romulo G. Davide, then professor of Plant Pathology in the University of the Philippines Los Banos (UPLB), thought testing the capability of the fungus Paecilomyces lilacinus Strain 251 (PL 251) as a biological nematicide.
PL 251, which in 1980 can only be found in the Philippines, is parasitic to all stages of development of common plant-infecting nematodes particularly root knot, potato cyst, and spiral and burrowing nematodes. In their vermiform stages, nematodes are infected as they migrate through the soil. The infection starts when a spore of the fungus adheres to the cuticle and then germinates. The growing fungus then overwhelms the nematode and eats its body.
In 1986, UPLB passed the technology to a private Filipino company for further development and commercialization. It was named “BIOACT”, but eventually, it was controlled by Australian corporations until 2000 when the Davao-based Biotech Resources for Agriculture & Industry, Inc. reclaimed the rights on it.
After the initial BIOACT formulation was registered in 1989 at the Fertilizer and Pesticide Authority, it was extensively tested and sold to banana exporters in Mindanao. But they had problems with the initial formulation.
First, the product could not be used in standard spraying equipment or in irrigation systems because it contained insoluble materials from the growth substrate. Second, it cannot effectively control nematodes because it only contained 1 x 109 spores of PP lilacinus per gram, considering also that its recommended application rate was i g per banana mat at two cycles per year. Hence, the product was not marketable.
In 2001, the German company PROPHYTA Biologischer Pflanzenschutz GmbH was granted a license to manufacture BIOACT formulations and sell it in the Philippines. It was reintroduced in 2002 as “BioAct®WG”. It was a water dispersible granular formulation, and the soluble carrier for the spores was glucose because it was found out that P. lilacinus promotes root devela nment when it is combined with glucose. However, the intimate association of the living spores with glucose affected the shelf life of the product.
But now that the glucose and the BioAct spore powder are sold separately, the product can last for at least six months if stored at 20°C and for two years if stored at 4°C. It now contains 1 x 1010 spores of P. lilacinus.
The improved formulation of BioAct®WG is already registered in many countries and this year, it was granted a registration at the European Union.
Aside from bananas, BiaAct®WG can be applied also to black pepper, citrus, coffee, cotton, grape, okra, papaya, peanut, pineapple, potato, ramie, strawberry, sugarcane, tea, tobacco, tomato, legumes, cut flowers, turf, and other ornamentals. More importantly, it was found out that PL 251 has also a beneficial effect on the root development of the plant. It’s because the fungus produces chitinase, an enzyme that promotes root development. Moreover, soil treated with PL 251 contains more saprophytes, which break down the organic matter in the soil so it can be absorbed by the plants.
It seems that the enhancement of root development is also caused by the blooming of the soil saprophytes in the plant rhizosphere, resulting in the abundance of plant nutrients. This explains why the roots of banana plantlets treated with BioAct®WG are almost three times bigger than the roots
of untreated plantlets.
To find out if BioAct®WG has a similar beneficial effect on the roots of mature banana plants, and if it improves production, nine demonstration farms were established in south eastern Mindanao in 2003.
Initially, 0.4 g (4 x 109) of BioAct®WG was applied to banana plants every six months, but this was found to have little or no effect at all on the roots. In March 2004, the application rate then was increased to 1 g(1 x 1010), and after two applications, there was a significant increase in the weight of fresh functional roots of banana plants.
It was also found out that regular application of BieAct®WG to Cavendish bananas results in higher yields. In the demonstration farm in Compostela Valley, for instance, the weight of each bunch of banana increased by 6.6 kg. This increased the production per hectare by 1,300 boxes of bananas and it would amount to an added income of $3,000 per hectare each year. It was also found out that with regular application of BioAct, an average banana plantation would earn an additional income of over P70,000 per hectare each year.
Table 1. Summary of the improvement in banana production in average bunch weight and in weight of boxed bananas per bunch in the last harvest in nine BioAct demonstration farms in Mindanao.
PLANTATION INCREASE IN HARVESTED INCREASE IN
BUNCH WEIGHT BOXED BANANAS
(KG) (KG)
Compostela*L 8.6 August 2006 6.6
Magatos*L 6.3 November 2006 6.2
Dacudao+M 4.5 October 2006 5.1
Tamayong+H 3.7 October 2006 2.1
Tanglaw*L 3.3 June 2006 0.8
Sampao*L 2.9 June 2006 3.2
Sampao+L 2.0 September 2006 2.8
UBC Tiboli 1 +H 2.0 July 2006 2.8
UBC Tiboli 2 +H 1.7 August 2006 3.8
Average 4.0 kg 3.7 kg
Established Plants; + New Planting
L-Lowland M-Midland H-Highland
