Soybean makes its demands Soybean makes its demands Argentine fields have taken on a very different aspect in recent years. Making up the difference are oilseeds, notably soybean. The deficit between the application of potash as fertilizer, and its removal by crops is now more than 1.5 million t K2O annually.
Potassium is a versatile nutrient in plants and is involved in many metabolic processes.
In other words, plants cannot be forced to take up more nitrogen if potassium is in short supply. K. This is partly because K is involved in the control of the plant's stomata, and hence water loss. If the ratio of potassium to nitrogen is out of balance, plants develop soft tissue which is highly vulnerable to chewing and sucking insects or the penetrating hyphae of fungal diseases. Plant breeders may do much to build resistance into varieties but their efforts, and the cost of the seed, is wasted if plant nutrition is unbalanced. It will be much less costly, in Argentina as elsewhere, to address the issue of restoring balanced soil fertility sooner rather than later and before the point at which the soil chemical properties are so changed that yields are badly affected - and the momentum of the last decades is lost.