The sun rises on crop diversity
Maize (corn) monocultures are a common sight on Hungary’s Northern Great Plain. But as with any monoculture herbicide resistance is always a potential danger. Istvan Szolomajer discovered the appropriately named Panicum riparium in his maize fields in 2010. But he didn’t panic. Since then, crop rotation has helped him tackle this resistance threat and sunflowers are now grown on half his cultivated land.
Istvan Szolomajer farms 350 ha of land in Mérk-Vállaj, a small community in northeast Hungary close to the Romanian border. In earlier times, the area was a swamp but improved irrigation has resulted in highly fertile “black soil”. After the collapse of Hungary’s communist regime, farmers were able to take possession of the land previously cultivated by agricultural cooperatives. That was how Istvan and his family came to own their farm. The climatic conditions in this part of northeast Hungary – somewhat wetter than elsewhere in the country – are ideal for maize. That was one reason why these monocultures emerged; the other was that maize is a very profitable crop. All seemed to be going well until 2010 when Istvan discovered Panicum riparium growing on his fields.
Is it even a weed?
Panicum riparium is a bit of a botanical rarity and certainly a relatively new indigenous species of flora in Central Europe. Experts call it a neogen species that probably originated in situ from the North American Panicum capillare. In several countries it is merely regarded as a wild plant, not a weed. But since one definition of a weed is “any wild plant growing in an undesired place”, the fact that Istvan’s maize fields were soon heavily infested with Panicum riparium meant that as far as he was concerned, this is a weed – and a highly problematic one too. Initially, Istvan and his fellow farmers used ALS inhibitors to control this weed, but after several years of application, there was strong evidence of an emerging resistance problem.
The rising sun
Istvan’s solution to the resistance problem was to replace maize monoculture with crop diversity – changing from monocot to dicot crops and from spring to winter crops, for example. This year, he has been growing sunflowers on 100 ha, winter wheat on 50 ha, and maize on most of the remaining 200 ha under cultivation. This crop diversity has brought Istvan welcome relief from resistant Panicum riparium. But there is one significant drawback: maize is the most profitable crop in that area and crop rotation means reduced profits. But with Istvan’s son-in-law now co-managing the farm, he is prepared to accept lower profits now for the prospect of a sustainable agricultural future for his family.
An integrative opinion leader
Close cooperation with Bayer staff in Hungary has been a crucial factor in Istvan’s diversity strategy. “When I notice something new on my fields – different weeds or different plant behavior – I contact Bayer to get help and find out what’s going on,” Istvan says. With not much local knowledge about the Panicum riparium threat, samples were sent to the Bayer Weed Resistance Competence Center in Frankfurt, Germany, for in-depth analysis. “I’m very open for new ideas,” Istvan says, “and when I learn things, I pass this knowledge on to my fellow farmers in the area.” Istvan is very much an integrative opinion leader. His machinery capacity – drilling, spraying, cultivating and harvesting equipment – is enough for another 650 ha. His warehouse can take the yields from 700 ha. His drying facilities are sufficient for around 15,000 t a year. All this gives Istvan a key role in informing, interacting with and influencing his fellow farmers. And the message he communicates to them is simple: “Crop and cultivation diversity is the answer to resistance problems in monocultures.”