Some relationships can be complicated. Take the one between sweet potato crops and soil nitrogen, for example.
Too little nitrogen and sweet potato plants don’t grow well and have low yields. Too much nitrogen, however, boosts the growth of leaves and branches at the expense of storage roots. That also leads to low yields.
“Carefully managing soil nitrogen levels is essential to obtain high yields from sweet potato crops,” says Adalton Fernandes, an agronomist at the Center for Tropical Roots and Starches at São Paulo State University in Brazil.
Fernandes is the lead author of a new study that determined how much nitrogen is needed to maximize yields from sweet potato crops in Brazil.
The researchers discovered field history matters when trying to apply the optimal amount of nitrogen for sweet potato crops. Cover crops grown in the same plots prior to sweet potato crops affected how much nitrogen was needed.
Read more at American Society of Agronomy
Image: Fernandes removing the sweet potato roots from soil to show their development pattern at harvest (Credit: Elder C. Mattos)