SWEET MAIZE (ZEA MAYS L. SACCHARATA) WEEDS INFESTATION, YIELD AND YIELD QUALITY AFFECTED BY DIFFERENT CROP DENSITIES

Weeds are among main limiting factors in sweet maize production. Commercially grown sweet corn hybrids (Zea mays saccharata Sturt.) vary widely in competitive ability against weeds which interference differentially affects yield and ear traits important to processing and fresh markets. A total of 28 sweet corn hybrids of different FAO maturity groups have been developed at the Maize Research Institute, Zemun Polje, and released by the the Commission for the Variety Releasing. In order to obtain high yields of good quality the scientists have been searching for the most appropriate growing practices. Therefore the objective of the present study was to determine the effect of four plant densities (40 000, 50 000, 60 000, and 70 000 plants/ha) on the level of weed infestation, yield and shelling percentage of four sweet maize hybrids (ZP 424su, ZP 462su, ZP 504su, and ZP 521su) in 2008 and 2009. Total fresh weight and the total number of weeds decreased with increasing sowing density, which was more prominent in 2008. Results of the analysis of variance showed that investigated factors, year, sowing density and hybrid had significant influence on fresh ear yield and shelling percentage. Sowing density affected fresh ear yield in the way that the denser sowing was, the higher yield was. Hybrids ZP 424su and ZP 462su gave higher fresh ear yields than other two. However, hybrids with less fresh ear yield (ZP 504su and ZP 521su) gave better shelling percentage. These results suggest that ZP 424su and ZP 462su can be preferable for fresh consumption and ZP 504su and ZP 521su for processing.