STATlSTICL STUDIES FOR EVALUATION SOME VARIETIES OF WHEAT

Two field experiments were conducted at the Agricultural Research Station,
Dakhlia Governorete of Tag El—Ezz during the two successive seasons of 200212003
and 2003f2004. Eight genotypes of wheat namely Sakha 8, Sakha 61, Sakha 59,
Sakha 92, Giza 163, Giza 164, Gemmiza 3 and Gemmiza 7.The treatments were
arranged in randomized complete blocks design with three replications. Analysis of
variance, simple correlation coefficient, predication equations of full model and
stepwrse multiple regression and principle.
The most important results can be summarized as follows:
Results indicate that wheat varieties exhibited significant differences for grain
yield per Spike and grain yield per plant as well as all studied yield attributes
Gemmiza 7, Sakha 92 and Gemmiza 3 had the highest grain yield per spike
and number of grainsrspiks. However, Gemmiza 7, Gemmiza 3 and Sakha 61 gave
heavier weight of 1000 grain. Moreover, Gemmiza 3, Sakha 92 and Sakha 69 could
be secured higher grain yield per plant.
Highly significant and positive correlation coefficients were found between
grain yield per spike and each of all characters except for plant height (cm), extrusion
length (cm), number of spikes and number of tillers. Grain yield per plant (g) was
found to be highly significant and positive correlated with all characters except plant
height (cm), extrusion length (cm), number of sipkeits and number ofgrains/ spike
model regression including all factors ranged from 93.17% to 96.51% and 98.74% to
99.62%, while stepwise regression ranged from 80.15% to 94.02% and 81% to
96.09% with grain yield per spike and grain Yield per plant, respectively. It found that
the most important macro climatic factors and variables affecting ie. grain yield per
spike and grain yield per plant were spike length (X6), number of spikes, weight of
1000-grains (g) (X13), number of grain per spike (X10), soil mean temperature at
depth of 20 cm from planting to end of anthesis (Mtepso4) and relative humidity from
planting to end of grain filling (RH5%) and growing degree-days from planting to the
end of booting (GDD3).
The principle component analysis grouped the studied variables in the
component accounted for 100% of the total variation with grain yield per spikes. The
result showed that two major components, which altogether accounted for 99.711% of
total variation. The first component included to flag leaf length, flag Ieafarea, number
of spikes, number of tillers and number of grain per plant. The second component
included the remainder characters.