The markets were busy consuming what the China / US phase one trade deal really is. The deal includes food and agricultural products so will have to be thoroughly understood to work out the impact on grain prices.
This didn’t stop the market from reacting in the usual manner though. Soybeans enjoyed some upside while corn and wheat went sideways. About all I can find at the moment is a rough guide of the US side of the equation which simply put is a transition from increasing tariffs to decreasing tariffs.  All this hinge on China buying US$50Bn in US goods in 2020, somehow I think they still have a long way to go.

Rabobank analyst remain sceptical considering total US exports of many of the listed products only amounts to US$57 – US$74Bn. The Chinese are unlikely to buy US product if it is not competitive with world values. It appears that the US is trying to create a premium for US sales into China in order for China to see US tariff relief. Nice market manipulation if you can pull it off. In theory it would probably see world values of some commodities increase as the world determines if China will indeed buy US product above market value.
If the China / Australian WTO trade dispute over barley is any indication it simply tells me China will do what China bloody well wants to do. So who are the winners of all this, well probably Russia. If export values increase and Russia is the shortest path to Market into China, it’ll become simple maths.
Iran picked up at least 260kt of Russian wheat overnight, there is talk of another 120kt of German wheat being bought.