İlknur Akgün

Determination of Variations of Some Enzymes in Orchardgrass ( Dactylis glomerata L.) Ecotypes

In the present study, wild orchardgrass ( Dactylis glomerata L.) collected from four different locations (Oltu, Olur, Uzundere and Uluba < ) of Erzurum (Turkey) were used to investigate various electrophoretic analyses within and between four ecotypes based on peroxidase (PRX), polyphenol oxidase (PPO) and malate dehydrogenase (MDH) enzymes. Four natural populations of Dactylis glomerata showed genetic variability within and among ecotypes based on similarities and polymorphism of isoenzyme bands. In addition, a dendogram analysis was made according to band patterns indicating that ecotypes could be grouped showing characteristics in relation to each other, notably Oltu-Uluba < and Olur-Uzundere. However, the degree of relationship of Oltu-Uluba < (6 units) was higher than Olur-Uzundere (12 units).

Seed set and some cytological characters in different generations of autotetraploid perennial rye (Secale montanum Guss)

Abstract Artificial autotetraploids of diploid perennial rye (Secale montanum Guss) plants were obtained by colchicine treatment. C1 C2 and C3 generations of autotetraploid perennial rye were compared for seed set and cytological characteristics such as irregularities in metaphase I (univalents) and anaphase I and II (lagging chromosomes and/or chromatids and bridge formation) and micronuclei in tetrads. In the three generations (C1 C2 and C3) the percentage of cells with univalents was 18.51, 14.56 and 9.38% respectively. The percentage of cells with irregular anaphase I with univalents was 23.43, 15.93 and 7.85%, and for anaphase II cells it was 20.93, 16.47 and 7.16. The percentage of tetrads with micronuclei was 18.17, 14.07 and 6.17% and seed set was 27.72, 43.51 and 59.59% respectively. A negative correlation was found between seed set and the cytological characteristics investigated. The correlations among the characters investigated during meiosis division were statistically significant. Selection of vigorous plants of autotetraploid perennial rye increased seed setting by increasing the cytological balance. However, abnormalities in the early stage of meiosis division were reflected in the later stages of meiosis.

AUTOPOLİPLOİD YEM BİTKİLERİNDE TOHUM ÜRETİMİ ÜZERİNE ANEUPLOİDİNİN ETKİSİ

OZET: Cesitlerin devamliliginda en onemli husus uretim esnasinda hicbir genetik degisikligin ortaya cikmamasidir. Bununla birlikte tohumla uretilen turlerde her uretim cemberinde gamet, zigot, tohum ve bitki seviyesinde dogal bir seleksiyon vardir. Yapay autopoliploidlerde ozellikle ilk generasyonlarda aneuploidler yuksek oranda bulunmaktadir. Aneuploidler tohum verimini dusurdugu gibi uretim esnasinda ortaya cikan seleksiyon islemlerini de etkilemektedir. Yapay olarak elde edilmis turlerin aneuploidiye karsi toleranslari farkli olup, bazi turlerde euploid bitkilerde dengesiz kromozom ayrilisi egilimi daha fazladir. Euploidlerde gorulen bu kararsizliga cevresel faktorler (hava, polen uretim miktari, bitki yogunlugu gibi stres kosullari) onemli derecede etki yapmaktadir. Dengesiz kromozom ayrilisi gosteren gamet ve zigotlarin canli kalabilme sansinin yuksek olmasi nedeniyle, bu turlerde aneuploidlerin tamamen populasyon icerisinden seleksiyonla uzaklastirilmasi cok zordur.

BAZI TRİTİCALE GENOTİPLERİNDE KENDİNE VE YABANCI TOZLAŞMA ORANLARININ BELİRLENMESİ

OZET: Erzurum ekolojik kosullarinda 1995-1996 urun yilinda triticalenin 2 cesit ve 3 hatti ile yurutulen bu denemede yabanci tozlasan, kendine tozlasan ve islem uygulanmamis basaklarda basaktaki tohum sayisi, tohum tutma orani ve tohumlarin 1000-tane agirligi uzerinde durulmustur. Deneme sonucunda, incelenen her uc ozelligin uygulamalara gore onemli derecede farklilik gosterdigi, buna karsin genotipler arasindaki varyasyonun yalnizca 1000-tane agirliginda onemli oldugu belirlenmistir. Kastre edilmis, kendilenmis ve islem uygulanmamis basaklarda tohum sayisinin sirasi ile 2.14-3.59, 12.22-13.17, 16.15-17.90 adet, tohum tutma oraninin %10.70-16.30, %61.12-66.90, %80.90-89.52, 1000-tane agirliginin ise 16.03-25.24, 42.69-47.76, 41.30-48.12 g arasinda degistigi tespit edilmistir. Triticalede yabanci tozlasma oraninin dusuk oldugu (ort. %13.59) ve bu ozelligin genotiplere gore cok az degisiklik gosterdigi saptanmistir. DETERMINATION OF PERCENTAGE OF SELF AND CROSS POLLINATION IN SOME TRITICALE GENOTYPES ABSTRACT: This study was conducted under Erzurum conditions in 1995-1996 season with 2 triticale cultivars and 3 triticale lines. Grain number per spike, percentage of seed set and 1000-grain weight in cross pollinated spike, self pollinated spike and intact spike were determined. In this researche, three characters studied significantly varied with the treatments, whereas variation only 1000-seed weight among the genotypes was significant, for the emasculated, self polinated and intact spikes, seed number were 2.14-3.59, 12.22-13.17 and 16.15-17.19, percentage of seed set 10.70-16.30%, 61.12-66.90% and 80.90-89.52%, and1000-grain weight 16.03-25.24, 42.69-47.76 and 41.30-48.12 g respectively. These result indicated that the cross pollination of triticale was lower (avg. 13.59%) and this characters showed slight variation among genotypes.