Sürdürülebilir Kalkınma Amaçları
Yayınlar
- MakaleAçık Erişim2011Heat and drought resistance criteria in spring bread wheat (Triticum aestivum L.): Morpho-physiological parameters for heat tolerance
Bahar, Bilge; Yildirim, Mehmet; Yucel, Cemal
This study was aimed at evaluating some morpho-physiological parameters such as stomatal conductance (gs), canopy temperature (CT), canopy temperature depression (CTD) and stay green duration (SGD) in terms of heat tolerance. For this purpose, trials designed according to randomized complete blocks were conducted with twenty-four spring bread wheat genotypes as three replicated in the Research and Application Area of Field Crops Department of Agricultural Faculty of Cukurova University in 2002 to 2003 and 2003 to 2004 growth seasons. The measurements of gs were made at two different dates at heading stage in 2003 to 2004 growth season. CT was measured at two growth stages (late milky and soft dough) in 2002 to 2003 (first) season and it was also measured at two different hours at the complete heading stage in 2003 to 2004 (second) season. CTD was measured at two different hours at the complete heading stage in the second season. The other morpho- physiological parameter was SGD, which was determined in the first growth season. As a result: (1) The high gs values were observed at both measuring dates even though there was no significant differences among the genotypes; (2) CT showed significant differences except T2 measurement in 2003 to 2004 season, yet significant negative correlations were found between CT and grain yield (GY) in 2003 to 2004 season and in general mean; (3) Despite not being significant differences among the genotypes, a strong positive correlation was found between CTD and GY; (4) In spite of the fact that genotypes did not show any statistical differences, it was found that SGD had a negative significant correlation with CT but positive non-significant correlation with GY. It is concluded from assessments of all physiological traits that such genotypes as Kauz/Altar 84//Ads, Varona Cno 79, Mon's'/Ald's'//Bow's' and WL6718 can be high yielding even if under heat stressed conditions, and can be used as gene pool in wheat breeding programs for tolerance to heat stress.
- MakaleYalnız künye2010Responses of some wheat genotypes and their F2 progenies to salinity and heat stress
Yildirim, Mehmet; Bahar, Bilge
Both heat and salinity cause yield decrease in wheat. Grain yield in wheat has increased as a result of breeding efforts for different stress conditions. However, there are still substantial opportunities to improve grain yield by using conventional breeding under stress conditions, like heat and salt stress. The objective of this study was to investigate heat and salt effects on yield and some agronomic traits of four wheat genotypes and their six half F2 diallel cross progenies grown in pots. Significant differences were found among the genotypes for grain yield under both heat stress and non-stress condition. There was a mean reduction in yield of 12.6% due to salt stress. The reduction in biomass was higher than grain yield under salt stress while it was lower at heat stress. Grain yield was positively correlated with spike weight, harvest index, grain numbers per plant and biological yield under non stress (NS), heat stress (HS) and salt stress (SS) conditions. Cultivars Seri 82 and Chil's had high yield among parents under both NS and SS. Chil's and its hybrids showed low reduction in yield due to SS; thus, exhibiting salt tolerance. Also, Chil's was found to be good combiner with high General Combining Ability (GCA) effects for grain yield under SS conditions. 84 CZT04 was the most susceptible cultivar under SS. Significant GCA effects of Genç 99 and 84CZT04 provided positive contribution to grain yield under HS. It was impossible to select both heat and salt tolerant genotype with high yield capacity from the used genotypes. However, heat or salt tolerant genotypes can be improved by selection breeding due to genetic variation among genotypes.
- MakaleYalnız künye2010Heat and drought resistances criteria in spring bread wheat: Drought resistance parameters
Bahar, Bilge; Yildirim, Mehmet
Some spring bread wheat genotypes were evaluated for drought resistance using drought tolerance efficiency (DTE) and drought susceptibility index (DSI) under rainfed conditions in this study. Field trials were conducted in the Research Area of Field Crops Department, Agricultural Faculty, Cukurova University during 2002 - 2003 with high rainfall and 2003 - 2004 with low rainfall growth seasons. High variations were observed for drought resistance parameters both DTE and DSI in this study. While DTE values ranged from 65 - 98%, DSI values changed 0.077 - 1.761. The genotypes with high DTE and low DSI were evaluated as drought resistant; meanwhile, genotypes with low DTE and high DSI were considered as drought susceptible. Thus, genotypes Croc 1/Aegilops squarrosa, Genc 99, Weawer/WL 3926, Oasis/Kauz//*4 Bcn, and Punjab 96 with the lowest DSI and the highest DTE values were accepted drought resistant genotypes which may be used as the genetic sources for drought resistance.
- MakaleYalnız künye2009Membrane thermal stability at different developmental stages of spring wheat Genotypes and Their diallel cross populations
Bahar, Bilge; Koç, Müjde; Barutçular, Celalettin; Yildirim, Mehmet
Yüksek sıcaklığa toleransta hücre zarlarının kararlılığı önemli bir fizyolojik seleksiyon kriteri olabilir. Yüksek sıcaklık membran kararlılığı, yüksek sıcaklığa maruz bırakılan yaprak dokusunun içerisinde bulunduğu sulu ortamdaki elektriksel iletkenliğin ölçümüyle belirlenmektedir. Bu araştırma, tarla koşullarında yetiştirilen 4 yazlık buğday anacı ve bunların altı F₂ diallel melez döllerinde, iki farklı yöntemle (MTS, yüksek sıcaklık membran kararlılığı ve RI, zarar indeksi) hesaplanan membran kararlılığının farklı gelisme dönemlerindeki değişimlerini belirlemek amacıyla gerçekleştirilmiştir. Ölçümler, yaprak büyümesi (erken vejetatif dönem), sapa kalkma ve erken süt olum evrelerinde gerçekleştirilmiştir. MTS ve RI ölçümleri üç farklı büyüme evresinde benzer eğilim göstermiştir. Bununla birlikte, büyüme evreleri genotiplerin MTS ve RI değerlerini önemli düzeyde etkilemiştir. Genotiplerin membran kararlılığı parametreleri büyüme evresi ilerledikçe azalmıştır. Tüm ölçümlerde özel uyum yeteneğinin genel uyum yeteneğine üstünlük sağlaması, memran kararlılığı özelliklerinin yönetiminde eklemeli olmayan gen etkilerinin etkin olduğunu göstermektedir. Erken süt olum evresinde bayrak yaprak membran kararlılığı, tane verimiyle önemli düzeyde ilişkili bulunmuştur. Anaçlardan Genç 99 ve 84ÇZT04 düşük verim, Chil’s ve Seri 82 yüksek verim potansiyeli göstermişlerdir. F₂ döllerinde tane verimi, başak verimi ve tane ağırlığı anaçlardan yüksek bulunmuştur. Bu sonuçlar, membran kararlılığı ölçümleri yönünden genotiplerdeki mevcut çeşitliliğin sıcak stresli çevrelerde buğday ıslahında kullanılabileceğini göstermektedir.
- MakaleAçık Erişim2009Membrane thermal stability at different developmental stages of spring wheat genotypes and their diallel cross populations; [Yazlık buǧday genotipleri ve diallel melez populasyonlarının farklı gelisme dönemlerinde yüksek sıcaklık membran kararlılıǧı]
Yildirim, Mehmet; Bahar, Bilge; Koç, Müjde; Barutçular, Celalettin
Membrane thermal stability (MTS) can be a significant selection criterion for heat stress tolerance. MTS is determined by measuring of electirical conductivity of aquause phase in which leaf tissue exposure to high temperature. This research was conducted to investigate the membrane stability assay measured by two different methods, namely MTS and relative injury (RI). The second objective of this experiment was to determine the effects of different growth stages of four spring wheat parents and their six half F2 diallel cross progenies grown in the field on membrane stability. Measurements were taken at different growth stages (seedling, stem elongation and early milk). The MTS and RI assays gave similar results at the three different growth stages. However, growth stages significantly affected the MTS and RI values of genotypes. Membrane stability parameters of genotypes decreased during the later developmental stages. Specific combining ability effects were superior to general combining ability effect for all measurements, indicating that membrane thermal stability was mediated mainly by non-additive gene actions. Membrane stability of flag leaf at the early milk stage was significantly correlated with grain yield. The parent of Genç 99 and 84ÇZT04 had low yield potential, whereas Chil's and Seri 82 had high yield potential. Grain yield, spike yield and kernel weight of F2 population were found higher than their parents. These results suggest that genetic variation among genotypes for membrane stability can be utilized in wheat breeding in heat-stressed environments.