Total Grower Services recommend the use of a Petrik Soil Technology program along with a modified fertiliser program for banana crops. We have successfully been using this approach in bananas since 2002. Our banana agronomy program is now almost considered conventional in this industry with 40% of growers now using Petrik products.
Benefits to Growers
A biological farming approach results in improvements in many areas. The combination of balanced soil chemistry and applied biology results in improved yields, more consistent quality, better plant health and superior disease resistance.
While we initially adjusted the soil chemistry looking to improve Sigatoka control we did notice a decline in activity of plant parasitic nematodes as well. The same cell wall integrity increases the plants resistance to pathogens attacking the foliage and the roots. While we do not have the same availability of data as for Sigatoka we have no growers using our whole program who are applying any nematicide. Management of the system is robust with most clients utilising monthly soil testing and leaf testing in order to fine tune fertiliser programs.
Fertiliser programs have also reduced the use of nitrogen and phosphorus. In all farms we have reduced nitrogen use by approximately one third while at the same time improving productivity. Phosphorus applications have been eliminated on most farms. Tissue phosphorous levels are now consistently higher under a biology program than they were previously when the farm was under a full phosphorous fertilizer program. This has been documented over time and is supported by university studies. The biological release of potassium, however, is generally much slower as this depends upon the breakdown of the actual clay particles. With a crop such as banana with a high potassium extraction this will never match crop demand. Potassium application requirements have actually increased in many cases as yields have gone up. With potassium it is pretty simple. If you take it away you need to replace it. We do not consider N and P in the same manner, however, as these have much stronger biological relationships and growing also means increased root exudates and a healthier soil which can often increase P and N availability by the actions of the soil biology.
There are further, more widespread, implications to sustainable farming in the North Queensland banana industry particularly with regards to run off to the Great Barrier Reef. Using Petrik products can reduce the environmental impact of farming by reducing the usage of nitrogen, pesticides and fungicides. This will help farmers meet the run off targets set by the government for 2018.
Products in Use
The mainstay of the banana industry has been Digestor. This robust combination of microbes suits the industry as it is sold ready to use and allows flexibility with application timing which is critical in the high rainfall environment.
Setbest foliar sprays support the soil biology. This is used 2-3 times per season to stimulate nutrient uptake in the plants. With even crops such as plant, first ratoon or nurse sucker this product is timed to maximise the nutrient content of the plant just prior to bunch initiation and bunch emergence. Setbest has also proven very effective at assisting the crop to overcome stress such as mite, chill or herbicide damage.
During our agronomic work with bananas we have optimised our custom foliar applications for banana crops. We apply tailor made mixes of products to the bananas depending on the nutritional values of the soil and tissue and our agronomists in-field survey results.