Author
Kiniry, James | |
ECHARTE, L - INTA BALCARCE |
Submitted to: Agronomy Journal
Publication Type: Research Notes Publication Acceptance Date: 7/13/2005 Publication Date: 9/15/2005 Citation: Kiniry, J.R., Echarte, L. 2005. Comments on "Yield response of corn in crowding stress" by Hashemi et al. Agronomy Journal. 97(5):1472. Interpretive Summary: Corn harvest index (HI) is an important component for computer models that predict corn yields and for plant breeding. Values near 0.5 have long been reported. In this paper, we compared the response of corn HI for a range of planting densities using data from the literature. Corn HI is relatively stable for planting densities of less than 10 plants m**-2. Above 10, HI shows a linear reduction with increasing planting densities. For modern hybrids a HI value of 0.54 is reasonable, with reductions causing HI to linearly decrease to near 0.375 at 30 plants m**-2. Technical Abstract: Maize (Zea mays L.) harvest index (HI) is an important component for simulation modeling and for plant breeding. Values near 0.5 have long been reported. In this paper, we compared the response of maize HI for a range of planting densities using data from the literature. Maize HI is relatively stable for planting densities of less than 10 plants m**-2. Above 10, HI shows a linear reduction with increasing planting densities. For modern hybrids a HI value of 0.54 is reasonable, with reductions causing HI to linearly decrease to near 0.375 at 30 plants m**-2. |