Grass pea (Lathyrus sativus L.) is an important protein source in arid regions as both human and animal food. Despite its significance, the use of grass pea is limited by the presence of β-N-oxalyl-L-a,bdiaminopropionic acid (β-ODAP) which can cause neurological disorders. Breeding studies in grass pea have therefore focused on developing high-yielding varieties with low β-ODAP content. However, the narrow range of genetic diversity and the restricted genomic tools in grass pea have slowed progress in such breeding. The present investigation was conducted to explore the genetic diversity of low β-ODAP germplasm consisting of 22 accessions with 31 EST-SSR markers. The molecular analyses revealed a total of 133 alleles ranging from 142 to 330 bp with a mean number of alleles per locus of 4.29. The mean polymorphic information content (PIC) value was calculated as 0.49, and the EST-SSRs in loci S5, S6 and S116 were of the most informative PICs. A dendrogram based on Nei's genetic distance matrix revealed that breeding lines were grouped in two main clusters. Genetic distances were higher between GP6/GP11, GP4/GP11 and GP5/GP8 accessions which could be further used in crop improvement studies for developing wider genetic diversity.

ÖzetBu araştırma, iki farklı mürdümük çeşidinin kuraklık stresine karşı toleransını belirlemek amacıyla Akdeniz Üniversitesi Ziraat Fakültesi Tarla Bitkileri Bölümü Laboratuarında yürütülmüştür. Bitkisel materyal olarak, Denizli ili, Acıpayam ilçesi, Yumrutaş köyünde uzun yıllardır yetiştirilen yerel bir populasyon ile düşük ODAP içeriğine sahip bir çeşit olarak tescil edilen Ceora çeşidi kullanılmıştır. Araştırmada, polietilen glikol-6000 (PEG 6000) kullanılarak 0, -2, -4, -6, -8, -9,8 bar su tutma gücüne sahip solüsyonlar ile 6 farklı kuraklık stresi oluşturulmuştur. Deneme 2 faktörlü ve 4 tekerrürlü tesadüf parselleri deneme desenine göre kurulmuştur. Çalışma sonucunda -8 ve -9,8 bar kuraklık seviyesinde çimlenme sağlanamamış, diğer seviyelerde başarılı çimlenme sağlanmıştır. Elde edilen sonuçlara göre, çimlenme oranı %90-100, kökçük uzunluğu 30.05-67.87 mm, sapçık uzunluğu 9.07-32.60mm, kökçük yaş ağırlığı 170.25-918.65 mg ve sapçık yaş ağırlığı 113.00-792.10 mg arasında değişmiştir. Sonuçta, 2 genotip arasında çimlenme oranı bakımından fark oluşmazken, fide gelişimi yönünde önemli fark bulunmuş ve yerel populasyonun kuraklığa daha toleranslı olduğu görülmüştür.Anahtar kelimeler: Mürdümük, Lathyrus sativus L., çimlenme, PEG-6000, kuraklık stresi. Assessment of Two Grass Pea (Lathyrus sativus L.) Varieties in term of Tolerance to Drought Stress AbstractThis research was carried out to determine the tolerance of two different varieties of grass pea (Latyhrus sativus L.) against drought stress in the Laboratory of Field Crops Department of the Faculty of Agriculture, Akdeniz University. A local landrace, which has been grown for many years in Yumrutaş village of Acıpayam district in Denizli province and the registered Ceora variety with the low ODAP content was used as plant materials. In the study, six different drought stresses were formed with solutions, which have 0, -2, -4, -6, -8, -9.8 bar water holding power respectively using polyethylene glycol-6000 (PEG 6000). The trial was established according to 2-factorial and 4-replicate randomized trial design. As a result of the study, germination was not observed at -8 and -9.8 bar drought level, while successful germination was observed in other levels. According to the results obtained, germination rate, root length, stalk length, rootlet fresh weight and stalk fresh weight ranged from %90-100, 30.05-67.87 mm, 32.60-9.07 mm, 170.25-918.65 mg and 13.00-792.10 mg respectively. As a result, while there was no difference in germination rate between 2 genotypes, it was found to be significant difference in seedling growth and local landrace was seen to be more tolerant.