A crop field with plastic mulching. Mulching reduces application of herbicides. The US is listing Roundup herbicide as a cancer causing product. Photo by Acolchado Plastico Agricola.
As the horticultural consumer countries move to blacklist one of the commonest chemical used in controlling weeds, Roundup, after links of its active component to cancer, experts say conservation agriculture and other strategies offer farmers one alternative solutions of penetrating the export market.
The United States of America’s California state will on July 7, 2017 officially include Roundup in the list of chemicals causing cancer, slapping back Kenya’s advances of exporting its horticultural products to this western country.
Glyphosate is the active ingredient in the herbicide, and the World Health Organisation listed it in 2015 as a carcinogenic element that puts consumers of goods produced from farms where it was applied at risk of developing cancer.
The fear in the horticultural sector is that US’s move is likely to trigger a similar action from the European Union – Kenya’s biggest horticulture consumer.
Festus Mutemi, an agribusiness expert in Machakos County said plastic mulching is one of the modern technologies of smothering weeds without using chemicals.
“It seems the consumer world is ganging against use of chemicals in production. Farmers cannot fight the market, when the consumer has a choice of buying from someone else who is complying with their standards. The farmers must , therefore, use alternative ways of limiting chemical applications in production to access these markets,” Mutemi said.
Plastic mulching involves tilling and raising seedbeds slightly before covering the area with a polythene lining. Planting holes are only drilled at the intervals of the recommended planting space.
The polythene smoothers both emerging and germinating seeds. Weeding will not be done until harvest, the agro-economist said.
This is also one of the most preferred methods of preventing loss of moisture since only a few outlets are available for soil ‘breathing’.
Mulching with organic materials also boosts the soil texture, but it may not be as efficient in smothering weeds as the polythene mulching.
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With the absence of weeds, Mutemi said, the application of fertilisers also decreases since the competition for nutrients is reduced too. Pests that hide on the weeds before attacking crops are also limited. This reduces pesticide application inadvertently.
Kenya exported at least 133,000 tonnes to the US in 2016. That was a growth from 130,000 tonnes in 2015 according to Kenya’s Horticulture Development Centre.
But a research by WHO’s International Agency for Research on Cancer in 2015 said the glyphosate may be carcinogenic, may pull down the prospects of raising the export to the US and other countries that may also adopt the regulation on imports.
Currently, the EU does not allow into its markets horticultural products with more than 0.02 parts per million of chemicals. The restrictions were reviewed from an earlier 0.2 parts per million maximum residue levels.