DETERMINATION OF OPTIMUM SEEDING RATE FOR SOME BREAD WHEAT GENOTYPES

wo field experiments were conducted at Agricultural Research Station of Etay-ElBarod, ElBehera Governorate during the two successive seasons of 2014/ 2015 and 2015/ 2016. To determine the optimum seeding rate for six bread wheat genotypes, i.e. 300, 350 and 400 grains /m2 on yield and yield components for six wheat genotypes, i.e. Sakha 94, Gemmiza 10, Gemmiza 7, Line 1, Line 8 and Line 6. Results indicated that Line 1 genotype exhibited shorter period to heading (96.89 and 98.56 days) and to maturity (146.23 and 145.11 days) in the first and second seasons, respectively. On the other hand, Gemmeiza 10 exhibited taller plants (123.50 and 121.06 cm) followed by Line 6 (119.83 and 117.72 cm) and Gemmeiza 7 (115.71 and 112.39 cm). While Line 1and Line 6 genotypes gave more number of spikes/m2 (417.00 and 395.00) and (406.22 and 390.56) spikes/m2 in the first and second seasons, respectively. The highest number of grains/spike was produced by Line 1and Line 6 (66.33 and 63.41) and (64.60 and 56.86) grains/spike, respectively. The highest values of 1000-grain weight were given by Line 1and Line 6 (62.32 and 60.39 g), (48.64 and 49.94 g). Line 1 and Line 6 recorded the highest grain yield fed being (29.53, 28.23 and 26.90, 25.62 ardab/fed) in the two seasons, respectively). Gemmeiza 7 gave the highest value of straw yield (7.62 and 7.45 ton /fed) for the first and second seasons, respectively. Increasing seeding rate caused a significant increase in the period to heading (98.67 and 99.50 days), to maturity (145.67 and 146.94 days) and number of spikes /m2 (405.67 and 404.67) but caused a significant decrease in plant height (112.10 and 105.51 cm) number of grain s/spike (62.58 and 59.03), 1000-grain weight (49.34 and 49.60g), grain yield (27.51 and 25.02 ardab/fed), in the first and ascend seasons respectively. Seeding rate of 300 grains/m2 caused a significant increase in plant height (110.01 and 103.41 cm), number of grains /spike (58.82 and 55.38 grains /spike), 1000-grain weight (49.34 and 49.60 g),grain yield (27.51and 25.02 ardab/fed) in the first and ascend seasons respectively. Simple correlation results indicate that the relationship between all possible pairs of the seven traits was highly significant at 1% level of significance in all cases. Significant and positive correlation was existed between grain yield and all studied characters. The results showed that the factor analysis under the study of the characteristics under the study to three factors under each of the rates of seedling, where these factors contributed to 78.11% of the total variation under the rate of 300 grains /m2 and 77.19% below the rate of 350 grains /m2 and T DETERMINATION OF OPTIMUM SEEDING RATE FOR SOME BREAD WHEAT GENOTYPES 1372 76.88% under the rate of 400 grains /m2. The study recommends the use of 300 grains /m2 of seedling when cultivating new genotypes and expanding the use of the most mature and most productive genotypes. Use of factor analysis by plant breeders has the potential of increasing the comprehension of the causal relationships of variables and can help to determine the nature and sequence of traits to be selected in a breeding program.