Our resident researcher, Ricki, drove up the West Coast last week to take part in the annual Swartland Kleingraan Ontwikkelingsgroep (SKOG) day. The day was held on the Langgewens trial farm, which is owned and operated by the Western Cape Department of Agriculture.
The day was based around twenty different trials conducted on the farm. These range from investigating the interactions between different crop rotations and tillage methods to the effects of biological fertilizers, ecological pest control and the growth of new crop varieties. Each trial was explained in detail to over two hundred farmers and industry representatives; including a number of Australian farmers and researchers who visited South Africa to conduct research on local agricultural systems.
Most interesting to note was that many of the trials have investigated the effects of biologically active products on promoting and conserving soil health whilst also stimulating crop growth and yields. It is vitally important that the fertilizer industry put its weight behind this movement as the good health of our soil is crucial to food security in South Africa. Furthermore, after speaking to the Australian researchers, it was interesting to find out that South Africa is slightly behind in the adoption of conservation agriculture principles. Farmers have utilized these principles down under for a number of years – leading to an increase in profitability and soil health.
One of the key pillars of conservation agriculture is the maintenance and improvement of soil biology. Soil life is vital to overall soil fertility since microbes, earthworms and micro-arthropods convert organic matter into plant-available nutrients. This is why the use of cover crops during the off-season is so important and ensures that a large (and diverse) amount of organic material is returned to the soil – feeding the microbes and providing nutrients for the following season. However, after decades of crop monocultures, the microbial diversity found in agricultural soils can be exceptionally low. This is particularly true in terms of beneficial organisms, and offers an explanation as to why pathogens flourish, even after annual applications of pesticides. Without the presence of natural competitors and the availability of an abundant food source (your crop), pathogenic organisms that include numerous species of nematodes, bacteria, fungi and insects can thrive.
Contemporary conservation agriculture techniques have shown that an increase in soil microbial diversity is linked to increased diversity in cover crop utilization. It is not uncommon for farmers to plant more than six different species of grasses, legumes and brassicas together in order to feed the soil microbes. To speed up the process of returning beneficial microbes to the soil, farmers often apply microbial inoculants and microbe foods to the soil. This was evident in a number of trials at the SKOG day, including trials concerning the applications of mycorrhizal fungi, humic acids, kelp extracts and fish emulsions. However, what was not indicated at any of the trials (and is of major significance) is the importance of the application of a diverse variety of beneficial microbes. The old adage of strength in numbers is certainly true, but couple that with diversity and you have a winning formula. Microbial diversity is key as it builds resilience in the soil ecosystem, reducing the amount of available ecological niches for pathogens and allowing for a large variety of microbial by-products to be produced. These products include plant growth hormones, pathogen inhibiting agents (such as lactic acid) and soil conditioning agents such as humus. These all contribute to increased soil fertility. Additional reading concerning the interaction between cover crops and microbial diversity can be found at:
Probio supported the event by supplying a number of prizes for the lucky draw after lunch. Two farmers walked away with five liters of BioAg each and numerous braaimasters won bottles of our probiotic degreaser Braai Clean, perfect for cleaning your braai grid.