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Yayın A new subspecies of Phoenix theophrasti Greuter (Phoenix theophrasti Greuter subsp. golkoyana Boydak) from Turkey(Istanbul Univ-Cerrahpasa, 2019-07) Boydak, MelihIn the present study, a new subspecies (Phoenix theophrasti Greuter subsp. golkoyana Boydak) is described in Turkey. The unidentified Phoenix taxon native to Bodrum-Golkoy, Aegean Turkey and named as the "Golkoy Phoenix population" has been known to Golkoy's inhabitants for centuries. The Golkoy Phoenix population was considered to be representative of P. theophrasti. Boydak made the first of a number of trips to Golkoy and immediately noticed some distinct differences between the Golkoy Phoenix population, P. theophrasti Greuter, and Phoenix dactylifera L in the early summer of 1990. He continued his investigations on this taxon for many years to shed light on the subject. He made two new trips to the three native stands of P. theophrasti and the Golkoy Phoenix populations in 2015 and 2018. Measurements and observations were made on the morphological characteristics that showed distinct differences among the Golkoy Phoenix population, P. theophrasti, and P. dactylifera. These were related to the length of male stalks and female inflorescences and some fruit and seed characteristics. The results indicate that some distinctive morphological characteristics of the "Golkoy Phoenix population" merit its being described as a new subspecies. "Phoenix theophrasti Greuter subsp. golkoyana Boydak" differs from P. theophrasti Greuter with respect to its longer fruiting-female stalk length and longer male stalk length, its fruiting stalks hold fruits marginally higher, and its having seeds with slightly visible striate surface crust structures and deeper-wider grooves.Yayın ISSR genotyping of Phoenix theophrasti natural populations in Turkey and Crete (Greece) and P. Dactylifera(John Wiley and Sons Inc, 2021-10) Boydak, Melih; Teker, Tuğba; Gazdağlı, Aylin; Thanos, Costas A.; Çalışkan, Servet; Kaltsis, Apostolis; Çalikoğlu Tozlu, Emine; Fournaraki, Christini; Albayrak, GülruhIntraspecific and interspecific diversity between Phoenix theophrasti individuals (92 from Turkey and 70 from Crete, Greece) and P. dactylifera specimens (28 from Turkey) were investigated by inter-simple sequence repeat (ISSR) analysis. A total of 45 polymorphic fragments, 360–3454 bps long, were produced. Intraspecific diversity for P. dactylifera was 26.63% and similarities ranged between 0.5 and 1. In the constructed dendrogram, P. dactylifera specimens clustered together in the first main group, outside branches consisting of P. theophrasti samples that generated the second main group. The intraspecific diversity for Turkish P. theophrasti populations was found to be 18.60% and for Cretan populations 13.45%. Antalya–Kumluca–Karaöz samples were grouped outside the branches of the remaining P. theophrasti samples. All three Cretan populations formed their own, separate branch. Datça–Eksera Stream samples together with two Datça–Hurmalıbük specimens constituted a group excluding Datça–Hurmalıbük and Bodrum–Gölköy specimens. Five Bodrum–Gölköy genotypes were clustered separately. Gene flow (Nm) values among populations were estimated from 0.157 to 59.615. AMOVA analysis revealed the percentages of variance among and within Phoenix populations: 73% and 27%, respectively. The first three principal coordinate components accounted for 37.60, 29.32 and 20.04%, respectively, thus the total variance obtained from the first three principal coordinate components was 86.96%. A positive correlation between geographic and genetic distances of populations was detected by Mantel tests (Rx,y = 0.44, p = 0.04). The populations were classified into four clusters by STRUCTURE analysis, supported the PCoA data. To conclude, ISSR results support that P. dactylifera and P. theophrasti are different species. Moreover, the findings not only revealed relationships between natural Phoenix theophrasti populations but also supported the identification of the P. theophrasti individuals that are phenotypically differentiated in the divided Bodrum–Gölköy population (P. theophrasti subsp. golkoyana).Yayın Effects of heat shock on seed germination of Turkish red pine (Pinus brutia)(Universidad Austral De Chile, 2016) Boydak, Melih; Çalışkan, ServetFire plays an important ecological role in Mediterranean-type ecosystems. Many Mediterranean plant species exhibit enhanced germination capacity when exposed to heat. In the present study, the effect of high temperatures and exposure times on germination of Turkish red pine (Pinus brutia) was analyzed in order to reveal the response of seeds to fire and the implications on species regeneration. Seeds were heated to a range of temperatures (from 75 to 170 ºC) and exposure times (from 30 seconds to 30 minutes) similar to those obtained in surface soil layers during natural fires. In total, twenty treatments were performed. Seed germination percentages and germination values were calculated for each treatment. The results of ANOVA performed for germination values showed that temperature had a significant effect. Germination percentages increased in thermal treatments at 70 ºC for 10, 15, 20, 25, and 30 min; at 105 ºC for 10, 15, 20, and 25 min, and at 130 ºC for 1 and 2 min. The increase in both temperature and exposure times generally decreased the germination percentage especially at 130 °C and over in comparison with the control. Maximum germination percentage was reached in the treatment at 130 ºC for 1 min while the minimum germination was reached at 130 ºC for 10 min.
