Hasan Pinar

Salt tolerance in Solanum pennellii: antioxidant response and related QTL

BackgroundExcessive soil salinity is an important problem for agriculture, however, salt tolerance is a complex trait that is not easily bred into plants. Exposure of cultivated tomato to salt stress has been reported to result in increased antioxidant content and activity. Salt tolerance of the related wild species, Solanum pennellii, has also been associated with similar changes in antioxidants. In this work, S. lycopersicum M82, S. pennellii LA716 and a S. pennellii introgression line (IL) population were evaluated for growth and their levels of antioxidant activity (total water-soluble antioxidant activity), major antioxidant compounds (phenolic and flavonoid contents) and antioxidant enzyme activities (superoxide dismutase, catalase, ascorbate peroxidase and peroxidase) under both control and salt stress (150 mM NaCl) conditions. These data were then used to identify quantitative trait loci (QTL) responsible for controlling the antioxidant parameters under both stress and nonstress conditions.ResultsUnder control conditions, cultivated tomato had higher levels of all antioxidants (except superoxide dismutase) than S. pennellii. However, under salt stress, the wild species showed greater induction of all antioxidants except peroxidase. The ILs showed diverse responses to salinity and proved very useful for the identification of QTL. Thus, 125 loci for antioxidant content under control and salt conditions were detected. Eleven of the total antioxidant activity and phenolic content QTL matched loci identified in an independent study using the same population, thereby reinforcing the validity of the loci. In addition, the growth responses of the ILs were evaluated to identify lines with favorable growth and antioxidant profiles.ConclusionsPlants have a complex antioxidant response when placed under salt stress. Some loci control antioxidant content under all conditions while others are responsible for antioxidant content only under saline or nonsaline conditions. The localization of QTL for these traits and the identification of lines with specific antioxidant and growth responses may be useful for breeding potentially salt tolerant tomato cultivars having higher antioxidant levels under nonstress and salt stress conditions.

Determination of genetic diversity among wild grown apricots from Sakit valley in Turkey using SRAP markers

Sequence-related amplified polymorphism (SRAP) marker was employed first time to analyze genetic diversity of 57 seed propagated early-maturated wild grown apricot genotypes sampled from different parts of Sakit valley in Mediterranean Region of Turkey. Of the total 19 primer combinations investigated, 16 could amplify clearly and consistently. They produced a total of 87 fragments, of which 56 (64.3%) were polymorphic bands. All bands obtained from Me3-Em2, Me2-Em10 and Me2-Em6 primers were polymorphic. The cluster analysis revealed that the 57 genotypes were grouped into three major clusters. The similarity ratio among genotypes was between 0.73 and 0.94. There were no identical genotypes. The study revealed that SRAP marker system was useful in identification and genetic diversity analysis of wild grown apricots.

Resistance of pepper lines against Meloidogyne incognita

Kok ur nematodlari ( Meloidogyne spp.) (Nematoda: Meloidogynidae)) biberlerde onemli urun kayiplarina neden olan bir zararlidir. Bu calisma 2010-2014 yillarinda Biyolojik Mucadele Arastirma Istasyonu Mudurlugu ve Alata Bahce Kulturleri Arastirma Istasyonu Mudurlugunde yurutulmustur. Elliyedi saf biber hatti Mersin ilindeki biber alanlarindan alinan Meloidogyne incognita (Kofoid & White) Chitwood, populasyonuna karsi 25±2.0°C testlenmistir. Nematod inokulasyonundan 60 gun sonra ur skalasina bakilarak degerlendirme yapilmistir. Testlenen biber genotiplerinden 27 adeti 0-2, 30 adeti 3-5 ur skalasi grubunda yer almistir. Dayanikli bulunan hatlar, farkli M.incognita populasyonuna karsi uc kez tekrar test edilmistir. Dayanikli hatlar ile hassas olan yuksek verimli hatlar melezlenerek verim degerleri alinmistir. Bunlardan 913XH9, 100XH8, N-269X1547 ve N269X953-W melez kombinasyonlari en yuksek verim performansi gostermislerdir. Yeni cesit adaylari kok-ur nematodunun ekonomik kayiplara neden oldugu tarim bolgelerinde ticari olarak kullanilabilir.