Corn sometimes has problems developing its nodal root system which causes plants to fall over when the plants get one to two feet tall. Normal shoot development often precedes this scenario, although nutrient deficiency symptoms may be observed, due to poor root exploration. This condition is often referred to as rootless corn syndrome. The ability of corn plants to recover from this condition depends upon favorable environmental conditions and why the nodal roots are failing to develop .
Corn has a two part root system consisting of seminal roots and nodal roots.
The seminal root system consists of the radicle and lateral seminal roots which develop below the seed. These roots temporarily anchor the seedling and take up water and nutrients during and shortly after emergence. The seminal roots cease growth by the V3 growth stage. The nodal roots begin developing at emergence and provide structural support and the bulk of nutrient and water uptake during the remainder of the plant's life. Thus, when the plants develop substantial size, they will fall over, since there is no lateral support for the stem.