Response of some yellow and white maize cultivars to plant densities and nitrogen fertilization : 1-growth characters

Abstract EN

The study was conducted at Sakha Agricultural Research Station Farm, during 1998 and 1999 seasons.

The purpose of this work was to investigate the effect of plant densities (47600, 59500, 71400 and 83300 plants per ha), nitrogen fertilization levels (-238, 286 and 333 kg N/ha) and their interactions on growth attributes of four maize cultivars, i.e.

S.

C.

10.

S.C.122 (white hybrids) and S.C.

155.

T.W.C.

352 (yellow hybrids).

The obtain results could be summarized as following.

Increasing plant density from 47600 to 71400 plants per ha led to a-significant decrease in number of green leaves per plant (GLN) AT 60 days from sowing (DFS) in 1988 season and at 50 and 60 DFS in 1999 season.

Also, stem diameter, leaf area per plant (LA).

Chlorophyll contents, as well as dry matter accumulation per plant (DM) were decreased significantly by increasing plant densities at 60 DFS in both seasons.

While, increasing plant density from 47600 to 83300 plants per ha increased significantly leaf area inded (LAI), plant and ear height in the two seasons.

The results obtained indicated that maize cultivars differed significantly in most of growth characters.

White maize cultivars (single cross-10 and single cross-122) exceeded the yellow cultivars (S.C 155 and T.W.C.

352) in GLN / plant, LA / plant, LAI, DM/plant, number of days to 50 % silking, plant and ear height and stem diameter at most sampling dates in both seasons.

GNL, LA / plant, LAI and DM/plant, chlorophyll content, plant and ear height, as well as stem diameter were increased with increasing nitrogen level from 238 to 333 kg N / ha.

The interaction between cultivars and N levels had significant effects on LA/plant at 50 DFS in 1988 season and on DM/plant and stem diameter in 1999 season as well as plant and ear height and stem diameter at 60 DFS in 1998 season.

The highest values of these characters were obtained by S.C.

10 cultivar fertilized with 333 kg N / ha.