Abstract:
Sowing date is an important factor to change of maize (Zea mays L.) yield in temperate zone. Delay to sowing
change to temperature for during the growth period. Crop could be damage for high temperature in some critical
period (seedling, grain filling). The objective of this study is determination of sowing date effect on yield, dry
matter accumulation, leaf area index and some growth parameters in maize crops. Two experiments were
conducted in the experiment from 2005 to 2006 with two maize hybrids (31G98 32K61). The treatments
consisted of different sowing dates. Cob yield, dry matter accumulations, leaf area index (LAI), net assimilation
rate (NAR) and crop growth rate (CGR) was measured.
The result of the study there was no significant differences among of the varieties in cob yield. The first year the
maximum dry matter yield was obtained 31G98 to the first sowing date. Optimum LAI values showed the same
variety in the same production period. The second sowing date in the first year of the highest dry matter yield
varieties gave 32K61. NAR and CGR curves obtained gave similar values. The first product resulting from the
NAR and CGR curves has more stable than the second product.