Plant protection products need regulation. But when that regulation becomes so stringent that product restrictions and losses affect the economics of growing a crop, management practices to mitigate the impact of regulation need to be adapted.
The Plant Protection Products Regulation 1107/2009, the Sustainable Use Directive (SUD) and the Water Framework Directive (WFD) have and will continue to condense the crop protection toolbox. And this will drive growers down a more integrated approach, says Adas’ James Clarke.
“The chemistry part of the equation will be less readily available or what it is able to do will be lower. So everyone will have to think about a rebalancing of cultural and chemical control.”
Lack of new active ingredients
The efficacy of products will not be as good as they were in the past, in part due to resistance, and there is likely to be a lack of new actives reaching the market due to the cost of development and regulatory hurdles being higher in the EU than other parts of the globe.
“Already, products with a lower level of efficacy than we used to think were required have made a satisfactory niche in the market such as prosulfocarb, which is now part of a suite of products [used] against grassweeds.”
The same may happen when the EU publishes the list of which actives fall foul of the endocrine disruptor definition.
“If a favoured triazole is lost and the next best available one delivers reduced efficacy, it will still be worth using, but growers will have to think what other chemical or cultural methods they need to do to reduce the pressure of disease.”
Increasingly growers will be looking towards improved genetics, although there may well be a gap between availability of new varieties and loss of products. More immediate measures will require a better understanding of all products and how to get the best from them.
Fine-tuning timings will be crucial to ensure the optimum timing is achieved for the pest, weed or disease. This will be helped by increased use of prediction models and thresholds, while the quality of application will also be critical, says Mr Clarke. “It is all attention to detail.”
But while integrated pest management (IPM) has always been supported by the agrichemical industry, implementation on individual farms has varied. However, the launching of the IPM plan as a legal requirement of the SUD will encourage growers to assess what they are currently doing and set themselves some priorities for their situation, adds Mr Clarke.
He identifies slugs and blackgrass as the two highest broad-scale challenges where integrated management will have to be more widely embraced, while more regional or local issues, such as oilseed rape herbicides restrictions due to the WFD, might affect specific farms.
But for integrated agronomy practice to meet the challenges of a reduced toolkit, agronomic research and knowledge transfer has to be integrated, too.
Already, the ban on neonicotinoids and pyrethroid resistance in cabbage stem flea beetle in the UK have prompted research into ways to get oilseed rape off to the best start to mitigate the effects of this damaging pest.
Agrii has looked closely at varieties that show early vigour, together with drilling date and establishment techniques. Seed rates and the use of seed treatments to improve rooting and establishment and the use of starter and placement fertiliser products have been and are continuing to be evaluated to help growers adopt a more integrated approach.
The firm’s 60,000 trial plots, which are devoted to looking at the interaction of decision support, genetics, crop protection, nutrition and cultivation, give an insight into the agronomic components and interactions which then have to be integrated at farm scale, says the firm’s David Langton.
“Farmers will have to get better at farming and agronomists must get better at agronomy if chemicals don’t work.”
Results from Agrii’s long-term blackgrass site at Stow Longa are being translated into on-farm advice showing growers how to make changes to improve control.
For example, growing more competitive wheat varieties at higher seed rates have resulted in 50% less blackgrass compared with a less competitive variety at lower seed rates, says Mr Langton.
With resistance in septoria to triazoles now getting desperate, every aspect of crop management has to be looked at, including stacked azoles, lots of multi-site, drilling date, nutrition, variety and future tools.
Two thousand wheat varieties in micro plots in south Wales are being assessed to identify ones with good septoria rating, says Mr Langton.
And in line with worldwide research and development expenditure swinging towards seeds and traits, Agrii is following suit, with the firm looking to produce their own Recommended List, which will contain more accurate disease and lodging ratings, grassweed competitiveness, second wheat suitability and other agronomic factors that should aid agronomists.