The Commission will investigate whether the deal could reduce competition in crop protection, seeds and certain petrochemicals, it said.

The merger, if it goes ahead, would create the globe’s largest integrated crop protection and seeds company, in industries that are already “globally concentrated”, the Commission said.

The EU’s competition commissioner Margrethe Vestager said: “The livelihood of farmers depends on access to seeds and crop protection at competitive prices. We crave to construct sure that the proposed merger does not lead to higher prices or less innovation for these products.”

In reviewing the planned deal, the Commission will see into competition in herbicides, insecticides, fungicides and nematicides, which are used to protect against nematode worms.

There are further concerns about a possible reduction in innovation in crop protection, as Dow and DuPont are both important innovators in this area, the Commission said.

Dow and DuPont both develop gene editing technologies that could be used to accelerate the breeding of recent seed varieties. The Commission said it is concerned that post-merger the companies could own fewer incentives to license these technologies to competitors or could construct the development of competing technologies more difficult.

The Commission will also see into whether competitors’ access to distributors of crop protection products and seeds could become more difficult if Dow and DuPont were to combine their sales of crop protection products and seeds, it said.

The Commission will also investigate the effect on competition and markets relating to the provide of specialty polyolefins, which are thermoplastics derived from petrochemical products and widely used in packaging and adhesive applications.

The Commission now has until 20 December to decide what action to grab in the case.