الفهرس | Only 14 pages are availabe for public view |
Abstract V.SUMMARY This study was carried out in the growth chamber, gree’nhoL’se and laboratories of the genetics Department, Faculty of Agriculture,. Ain- Shams University, Shoubra EI-Kheima, Cairo, Egypt, during the period from 2000 to 2003. The objective.s of this study were: first, to obtain reliable- information . about performance of yield components under salinity stress tolerance of three ”. bread wheat cultivars. Secondly objeCtive,’ to develop effective molecular :.. . . .marker associated with salinity tolerance to assist in breeding programs to select tolerant genotypes. The main results could be summarized as follows: 1~ Evaluate three Egyptian wheat cultivars differing in their Jolerance to salinity stress and differing also in their yield performance. 2. This is happen when these cultivars were planted in” sand cultur experiment in the greElnhouseand treated with salt solution. 3.The two selected cultivars, their F1 and F2 plants (300 ’individual plants) were tested for their salinity tolerance in s.andculture experiment according to their performance for. the following vegetative and mature yield- related .traits: plant height (~m),stem diameter (em), number of flag leaves, number of tillers! plant, number of spikesl plant, main spike length (em), main splk~ weight (gm), number of spikletsl main spike, number ’of grains! main spike, one hundred grain weight (gm), grain yield(·.plant (grn), biornass (g~) and harvest index. 4. The F2. plants (300 individual plants) were classified into two mainly ·groupsaccording to their behavior under salinity treatment. 5. The most tolerant and most .sensitive.plants were chosen from F2 and .were sampled along with F1 and tHeir parents to detect molecular genetic markers for salinity tolerance trait. ’. --- 6.’ Bulked segregant analysis was used to analyze DNA extract with /, .” RAPD-PCR technique for the two contrasting parents. their F 1 and two extremes of F2 groups (salinity tolerance and salinity sensitive). Using six ran~om primers (OP-A16, OP-B01, OP-B06, OP-B10, OP-B18. OP- ’ , . Z08). only primer OPA-16 showed clear-cut molecular -markers for salinity tolerance. 7. Fifteen pairs of SSR primers specific for bread wheat ”Yere used to ,develop some moleCUlar,markers associated with salinity tolerance using bulked segregant analysis CBSA). Only 11 SSR pairs showed polymorphism and 7 of them exhibited 7 molecular markers associated with salinity tolerance. |