أداء زهرة الشمس بتأثير موسم الزراعة و موعد الحصاد : 1-معايير النمو و حاصل البذور الزراعية

Abstract EN

An experiment was conducted at the farm of Field Crops Sta.

/ IPA Agric.

Res.

Center in Abu-Ghraib in 2000 and 2001.

It included five A- line inbreds, one R- line inbred and their hybirds.

The objectives were to investigate the effect of spring and fall planting seasons, stage and agricultural seeds of inbreds and their Fj seeds.

Hybrid vigor has reduced plant height to the half, and flowering time( in- the spring) from 84 d for inbreds to 75d for hybrids, and increased head area and number of seeds / head.

Pollination of A- line inbreds with R- line pollens increased F| seeds of some inbreds via increasing seeds / head.

Spring and fall plantings gave plant growth rate 14.7 and 12,5 g/m2/day, total dry weight 7.7 and 7.1 t/ha, seed growth rate 2.8 and 1.7 mg/d and seed weight 75 and 65 mg for both seasons, respectively.

Total plant dry weight, daily seed growth rate, and seed weight were increased with increased plant growth rate, but not influencing F| seed yield for it’s beared on inbred plants.

The most active plant growth rate (20.1 g/m^/d) was at 56 d after fertilization, while the most active seed growth rate (2.8 nig/d) was at 28 d after emergence.

Harvesting at maturity or one month later had no effect on seed weight or seed yield.

The interactions of genotypes by planting season and by date of harvest were significant.

It was concluded that to produce seeds of inbreds A| , A5 and their Fi seeds, and seeds of inbreds A,, , A9 and their F, seeds, their should be grown in spring and fall plantings, respectively and harvested one month after maturity.