A study was performed to evaluate the effects of environment (E) and genotype (G) × E interactions (GGE) for quality traits and grain yield in bread wheat (Triticum aestivum L.). ANOVA and GGE biplots were used to assess quality performance and stability in 36 genotypes of bread wheat through a three‐location trial over two cropping seasons in the Thrace Region of Turkey. The 36 wheat genotypes used were classified into eight different groups, including landraces, 1960s, 1970s, 1980s, 1990s, 2000s, and advanced lines. The data showed a wide range of variation for milling quality parameters with regard to gluten quantity and quality, as well as for grain yield. Genotypes, location, and year, in this order, contributed to this diversity. Remarkably, all the traits except grain protein content showed a larger genotype effect than location (L) effect; the interaction G × L was usually more important than the G × Y. Genotypic and location components markedly exceeded G × L and Y × L for all variables, with the exception of grain yield, in which the G × Y effect was greater than locations according to ANOVA analysis. Noticeable continuous progress (53%) was observed in genetic grain yield during the last 60 yr without limiting wheat quality. GGE biplot analysis found that, on average, the biplots accounted for 80 to 85% of G and G × E variation present. Krasunia and Sagittario were the best genotypes (best performance and higher stability) of the study based on the traits evaluated.

The interrelationships among the grain protein, oil, fatty acids, starch, Na, K, Fe concentrations and chemical grain characteristics were determined by correlation analyses in thirty-five commercial dent corn hybrids. An increase in oil content of the corn is accompanied by a decrease in starch content and by an increase in caproic acid content. The correlation coefficients involving protein content of corn hybrids with oil content (r = 0.066) and with saturated fatty acid (SFA) (r = -0.247*) evidence that protein content is more related to fatty acid distribution than the oil quantity. Linear relationships between refractive index (RI) (nD40 ºC) and saturated fatty acid (r = 0.369**) and between refractive index and oleic acid (r = 0.364**), and between iodine number (IN) and unsaturated fatty acid (UFA) were determined. In addition, oleic acid is strongly correlated with linoleic (r = -0.769**) and linolenic acids (r = -0.335**).

This research was conducted to determine the effect of genetic and phenotypic variability on the yield and yield components of some bread wheat varieties over a period of four years (1995)(1996)(1997)(1998). Experiments were established according to a completely randomised block design with three replicates in the Experimental Field of Tekirdağ Agricultural Faculty, Thrace University. In the present research, genotypic and phenotypic variability, heritability and phenotypic correlation coefficients were estimated for plant height, spike length, number of spikelets per spike, number of spikes per square metre, thousand kernel weight, test weight and grain yield per hectare.The results of data analyses showed that the highest genotypic variability was obtained for per hectare yield, whereas the highest phenotypic variability values were found for plant height, thousand kernel weight and grain yield. For plant height, thousand grain yield and test weight, the broad sense heritability coefficient was found to be the highest, while it was low for spike length, number of spikelets per spike and number of spikes per square metre.

The doubled haploid technology is now an integral component of modern maize breeding programs. In this study, the maternal haploid induction (gynogenesis) method was used to derive Doubled-Haploid (DH) lines from elite maize germplasm adapted to Turkey. Temperate haploid inducers (RWS, RWK-76, RWS x RWK-76 and WS14) were used as pollinators, and a set of 30 single-crossses (in FAO 650-700 maturity groups) were used as source materials. Putative haploid seeds were selected based on expression of R1-nj anthocyanin color marker. Highest haploid induction rate (20.42%) was recorded by using RWK-76 as inducer line, and the lowest haploid induction rate (17.75%) was obtained through WS14. Putative haploid seeds were germinated and seedlings were treated with 0.06% colchicine + 0.5% dimethylsulfoxide solution. Following transfer of seedlings into the field, 2178 D0 plants were obtained out of a total of 3012 treated haploids. Live plants were from 89% of 2178 seedlings which are planted to the field. Fertile plants were formed 57% of live plants. Inbreeding was succeeded in 31.23% of fertile plants and only 7.8% of inbreeding plants were able to produce seeds. Consequently, 27 doubled haploid lines were developed.

Ekmeklik buğdayda kuraklık stresi koşullarında çevresel ve genetik faktörlere göre değişiklikler gözlenebilen kök yapısı önemli faktör olarak değerlendirilmektedir. Araştırmada bazı ekmeklik buğday genotiplerinin farklı kuraklık seviyelerindeki kök ağırlıkları ile kök ağırlığının bazı fizyolojik karakterlere olan etkileri incelenmiştir. Araştırma, Trakya Tarımsal Araştırma Enstitüsü deneme alanında 2008-2009 ve 2009-2010 yıllarında yapılmıştır ve 15 genotip kullanılarak; tesadüf blokları bölünmüş parseller deneme desenine göre 3 tekrarlamalı olarak yürütülmüştür. Ana parsellerde beş farklı kuraklık uygulamaları, alt parsellerde genotipler yer almıştır. Araştırmada sapa kalkma döneminden fizyolojik olum dönemine kadar farklı seviyede kuraklık uygulanmıştır. Araştırmada kuraklık stresi uygulaması genotiplerde kök ağırlığını azaltmıştır. Genotiplerde en fazla kök ağırlığı Bereket çeşidinde (3.618 g) tespit edilmiştir. Kuraklık stresi bitkilerde kök ağırlığını farklı oranlarda etkilemiş olup, en düşük kök ağırlığı (2.815 g) tam kuraklık uygulanan parselde ölçülürken, en fazla kök ağırlığı kuraklık stresi uygulanmayan koşullarda belirlenmiştir. Araştırmada genotiplerde kök ağırlığının artışı başaklanma öncesi ve tane dolum döneminde bayrak yapraklarındaki klorofil kapsamını önemli ölçüde artırmıştır. Kök miktarı bütün kuraklık uygulamalarında bitki örtüsü sıcaklığını düşürmüştür. Bitkide kök miktarının genotiplerde başaklanma, olgunlaşma gün sayıları ve tane dolum süresini artırdığı belirlenmiştir. Kök ağırlığı artışında stoma eni ve boyunda artış olurken, stoma sayısında azalma olmuştur. Kök ağırlığına genotip ve çevre faktörleri etkili olurken yapraklarda klorofil kapsamında artış kanopi sıcaklığında azalma olmuştur.