Sustainable agriculture company Syngenta’s Africa Middle East Seedcare Institute, in Brits, focuses on new application technology, ensuring that seed treatments provide an effective way of placing crop protection products directly onto the seeds, Syngenta seed care technology manager Wayne van Rensburg tells Engineering News.
“The goal is to ensure that there is no negative impact on seed germination or vigour, thereby confirming the right amount of chemical is applied according to the registered dosage and dust-off of treated seeds is limited to subsequently ensure limited environmental impact and human exposure,” he explains.
Van Rensburg notes that the Syngenta Seedcare Institute focuses primarily on working with seeds partners to ensure seed care products are applied in accordance with regulatory requirements and environmental standards.
There are 11 seed care institutes worldwide, including Africa’s first, which is based in Brits, South Africa; Stein, in Switzerland; Holambra, in Brazil; and Stanton, in the US.
“Seed treatment can consist of several different active ingredients such as fungicide, storage insecticide, insecticide, micronutrients and polymers as binding agents, which are applied directly to seeds,” Van Rensburg explains.
He notes that these ingredients can be applied in several ways, including directly injecting active ingredients into seeds. “A four-nozzled seed treater sprays out a specific amount of each active ingredient onto a specific amount of seeds.
Another method would be to treat the seeds with a slurry mix, which would have all the active ingredients mixed into one container.”
Van Rensburg asserts that important factors when treating seeds should include the correct dosage rate of each active ingredient, uniformity of treatment, the flowability of the treated seed when packaging, the plantability of the seed, the dustiness of the treatment and good visual appearance.
“All these traits are tested at the Brits institute, with equipment ranging from the Heubach Dust Measurer to the high-performance liquid chromatography (HPLC) machine that tests the active ingredient loading seed chemical treatments,” he highlights.
There are six factors to consider when choosing a treatment for seeds – protection of the seeds, protection against pests, ease of application, how easy the seed is to plant, safety of operators and safety to the environment.
“We have a variety of seed treatment equipment at the institute to help us design or create an optimum seed care treatment for seed houses or for farm treatments for their specific needs.
“Once we have decided what type of treatments are needed, for example, fungicide or insecticide, we treat a sample of seed in our batch treater with the specific treatment. This enables us to monitor the effect of the treatment on the seeds.
“As soon as the seeds have been treated, they are placed in a flowability chamber, which measures the flow rate of the seed through a funnel system, which, in turn, determines the flow rate of the seeds during packaging and also the rate at which the treatment dries on the seed,” Van Rensburg explains.
He adds that the treated seed samples are then placed in a climatic chamber at a specific temperature and humidity for 48 hours, creating a constant temperature and moisture content for the samples.
“These samples are then placed in a Heubach Dust Meter for two minutes, which enables us to calculate the percentage of dust that comes off the treated seed. This dust includes the different ingredients applied to seeds – the more dust-off, the less efficient the treatment.
“Another important factor with regard to dust-off is health and safety. At Syngenta, seed treatment stewardship is important. We like to ensure that the treatment is safe not only for the operators but also the environment,” Van Rensburg asserts.
Active ingredient loading using the HPLC machine is another test performed at the institute. This process enables seed technicians to calculate the dosage rate of the treatment and, by doing so, determine if the seed was effectively treated.
“Before considering seed treatment, a farmer should consider the quality of the seed. A poor-quality seed will deteriorate over a short period, which will affect germination, subsequently decreasing the potential yield of the crop in the long run. “A poor-quality seed is also more susceptible to stress, which includes abiotic and biotic conditions,” Van Rensburg highlights.
He adds that it is important to be knowledgeable when considering seed treatment, as the best treatment, including the type of fungicides and insecticides to be used, should be selected for a potentially greater yield.
“Another important factor to consider is the storage conditions of the treated or untreated seeds. It is advisable to store them in a low- moisture and low-temperature zone and not in direct sunlight, as sunlight affects germination and seed quality,” Van Rensburg concludes.