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Line × Tester Mating Design Analysis for Grain Yield and Yield Related Traits in Bread Wheat (Triticum aestivum L.)  [PDF]
Zine El Abidine Fellahi,Abderrahmane Hannachi,Hamenna Bouzerzour,Ammar Boutekrabt
International Journal of Agronomy , 2013, DOI: 10.1155/2013/201851
Abstract: Nine bread wheat (Triticum aestivum L.) genotypes were crossed in a line × tester mating design. The 20 F1's and their parents were evaluated in a randomized complete block design with three replications at the Field Crop Institute-Agricultural Experimental Station of Setif (Algeria) during the 2011/2012 cropping season. The results indicated that sufficient genetic variability was observed for all characters studied. A899?× Rmada, A899?× Wifak, and A1135?× Wifak hybrids had greater grain yield mean than the parents. A901 line and the tester Wifak were good combiners for the number of grains per spike. MD is a good combiner for 1000-kernel weight and number of fertile tillers. HD1220 is a good general combiner to reduce plant height; Rmada is a good general combiner to shorten the duration of the vegetative growth period. A901?× Wifak is a best specific combiner to reduce plant height, to increase 1000-kernel weight and number of grains per spike. AA × MD is a best specific combiner to reduce duration of the vegetative period, plant height and to increase the number of kernels per spike. A899?× Wifak showed the highest heterosis for grain yield, accompanied with positive heterosis for the number of fertile tillers and spike length, and negative heterosis for 1000-kernel weight and the number of days to heading. , ? low ratios and low to intermediate estimates of h2ns supported the involvement of both additive and nonadditive gene effects. The preponderance of non-additive type of gene actions clearly indicated that selection of superior plants should be postponed to later generation. 1. Introduction Bread wheat (Triticum aestivum L.) is an important staple food in Algeria. This crop ranks third after durum wheat (Triticum durum Desf.) and barley (Hordeum vulgare L.), with a yearly cropped area of 0.8 million hectares, representing 24.2% of the 3.3 million hectares devoted to small grain cereals. Algeria imported 3.0 million tons of bread wheat in 2010/2011, to remedy the decline in the domestic production and to build stocks to meet the needs. Increasing wheat production can be achieved by application of improved agronomic technics, developing and adopting high yielding varieties. Major emphasis, in breeding program, is put on the development of improved varieties with superior qualitative and quantitative traits and resilience to abiotic stresses. In fact, genetic improvement in bread wheat, having better tolerance against terminal heat and water stress, has a good promise to improve grain yield average and total wheat production. However to breed high
ESTIMATING GENOTYPIC RANKS BY NONPARAMETRIC STABILITY ANALYSIS IN BREAD WHEAT (TRITICUM AESTIVUM L.)  [PDF]
Y KAYA,S TANER
Journal of Central European Agriculture , 2003,
Abstract: This study was carried out to determine the ranks of 9 bread wheat (Triticum aestivum L.) genotypes across eleven environments in Central Anatolia, Turkey, in the 2000-2002 growing seasons. Experimental layout was a randomized complete block design with four replications. Analysis of Non parametric stability revealed that genotypes 4 and 8 were most stable and well adapted across eleven environments. In addition, it was concluded that plots obtained by both mean yield (kg ha-1) vs. S1 (1) and mean yield (kg ha-1) vs. S2 (2) values could be enhanced visual efficiency of selection based on genotype x environment interaction.
Nonparametric stability methods for interpreting genotype by environment interaction of bread wheat genotypes (Triticum aestivum L.)
Akcura, Mevlut;Kaya, Yuksel;
Genetics and Molecular Biology , 2008, DOI: 10.1590/S1415-47572008005000004
Abstract: evaluation of performance stability and high yield is essential for yield trials conducted in different environments. we determined the stability of 10 bread wheat (triticum aestivum l.) genotypes (5 cultivars and 5 advanced lines) using nonparametric stability measures and compared nonparametric stability statistics across 19 environments in the central anatolian region of turkey. experiments were setup in a randomized complete block design with four replications. nonparametric stability measures revealed that al-2, karahan-99 and altay-2000 were the most stable and well adapted genotypes across the 19 environments. in addition, it was concluded that graphs of mean grain yield (t ha-1) vs. nonparametric measures (si(1), si(2), s(3), si(6) and σgy) values and kr vs. σr values could enhance visual efficiency of genotype selection based on genotype by environment interaction. furthermore, high top values, si(3) and si(6) were associated with high grain yield, but the other nonparametric stability measures were not positively correlated with grain yield and instead characterized a static concept of stability. choice of genotype for increased grain yield in bread wheat would, therefore, be expected to change yield stability by increasing the values of the si(3), si(6) and top nonparametric stability statistics.
RAPD Markers Associated with Drought Tolerance in Bread Wheat (Triticum aestivum L.)  [PDF]
H. Pakniyat,E. Tavakol
Pakistan Journal of Biological Sciences , 2007,
Abstract: Randomly Amplified Polymorphic DNAs (RAPDs) were used to search genetic diversity and markers associated with drought tolerance in 20 bread wheat cultivars. These cultivars are extensively being used by farmers in Iran, 6 of them are known as drought tolerant. Initial screens involved growing 10 cultivars at seedling stage under drought conditions (-5 and -8 bar) exerted by PEG 6000 in a hydroponic experiment. These tests confirmed the tolerance of the 6 above mentioned cultivars. Thirty 10-mer RAPD primers were used for fingerprinting of the cultivars of which primers P6 (TCGGCGGTTC) and P7 (CTGCATCGTG) produced respectively a 920 and a 750 bp band present in drought tolerant (absent in others) cultivars. These bands may be associated with drought tolerance in bread wheat.
Expression and functional analysis of TaASY1 during meiosis of bread wheat (Triticum aestivum)
Scott A Boden, Nadim Shadiac, Elise J Tucker, Peter Langridge, Jason A Able
BMC Molecular Biology , 2007, DOI: 10.1186/1471-2199-8-65
Abstract: The full length wheat cDNA and genomic clone, TaASY1, has been isolated, sequenced and characterised. TaASY1 is located on chromosome Group 5 and the open reading frame displays significant nucleotide sequence identity to OsPAIR2 (84%) and AtASY1 (63%). Transcript and protein analysis showed that expression is largely restricted to meiotic tissue, with elevated levels during the stages of prophase I when pairing and synapsis of homologous chromosomes occur. Immunolocalisation using transmission electron microscopy showed TaASY1 interacts with chromatin that is associated with both axial elements before SC formation as well as lateral elements of formed SCs.TaASY1 is a homologue of ScHOP1, AtASY1 and OsPAIR2 and is the first gene to be isolated from bread wheat that is involved in pairing and synapsis of homologous chromosomes.Meiosis is obligatory for sexual reproduction and is comprised of one round of DNA replication followed by two rounds of cell division. There are three key processes that occur during early meiosis which are responsible for the juxtaposition of homologous chromosomes required for successful production of haploid gametes, namely chromosome pairing, recombination and chromosome synapsis. Studies investigating the molecular nature of homologous chromosome pairing have revealed a complex relationship between these three processes.Complexity is particularly pronounced in polyploid organisms such as the allohexaploid bread wheat (Triticum aestivum). Bread wheat contains seven groups of chromosomes which are derived from three diploid progenitor species (AABBDD; 2n = 6× = 42). Despite the genome complexity of this important crop, each chromosome will pair only with its homologue, despite the potential for pairing with an equivalent chromosome from one of the other two related or homoeologous genomes. Extensive cytological analysis of chromosome dynamics during early meiosis in normal bread wheat and mutants such as Ph1 and Ph2 (pairing homoeologous),
Determining the Direct Selection Criteria for Identification of High Yielding Lines in Bread Wheat (Triticum aestivum L.) Bread Wheat (Triticum aestivum L.)
M. Asif,M. Yaqub Mujahid,Iftikhar Ahmad,N.S. Kisana
Pakistan Journal of Biological Sciences , 2003,
Abstract: A set of twenty elite bread wheat lines including one standard variety were evaluated in order to determine the selection criteria for identification of high yielding lines in bread wheat. The results showed that all varieties having highly significant variation for days to heading, days to maturity, plant height, 1000-kernel weight, test weight and grain yield. Grain yield was positively correlated with 1000-kernel weight and test weight while the other traits i.e, days to heading, days to maturity and plant height showed negative correlation. The results indicated that 1000 kernel weight had positive direct effect on grain yield. It was concluded that selection be made considering 1000-kernel weight and test weight.
Paraquat Tolerance of Bread Wheat (Triticum aestivum L.) Genotypes
Ozcan Caglar,Ali Ozturk,Murat Aydin,Sinan Bayram
Journal of Animal and Veterinary Advances , 2012, DOI: 10.3923/javaa.2011.3363.3367
Abstract: The drought stress in one of the most significant environmental stress limiting the plant production over the agricultural lands of the world. Since, the stress caused by the pesticide paraquat (1, 1-dimenthyl-4, 4 bipyridilium dichloride) is similar to water stress which decreases the chlorophyll content of the leaves, paraquat tolerance is successfully used to determine the wheat genotypes resistant to drought. This study was carried to determine the Paraquat (PQ) tolerance of 64 bread wheat genotypes. The parameters of SPAD values before and after paraquat treatments, chlorophyll loss caused by paraquat and correspondingly calculated Paraquat Sensitivity Indexes (PSI) was investigated in this study. Significant differences were observed among the wheat genotypes with regard to all of the investigated parameters. SPAD values of genotypes before PQ treatment varied between 33.6-51.3 and varied between 28.8-47.0 after PQ treatment. Chlorophyll loss of genotypes due to PQ treatments was between 2.0-23.3%. PSI values of genotypes were found to be between 0.18-2.10. The varieties Cetinel, 2000, Alparslan, Sultan 95, Karahan and KirmiziYerli were found to be the most tolerant and Ankara 093/44, Ak 702, Haymana 79 and Conkesme varieties were found to be the most sensitive genotypes.
Proteome characterization of developing grains in bread wheat cultivars (Triticum aestivum L.)
Guangfang Guo, Dongwen Lv, Xing Yan, Saminathan Subburaj, Pei Ge, Xiaohui Li, Yingkao Hu, Yueming Yan
BMC Plant Biology , 2012, DOI: 10.1186/1471-2229-12-147
Abstract: Proteome characterization during grain development in Chinese bread wheat cultivars Jimai 20 and Zhoumai 16 with different quality properties was investigated by 2-DE and tandem MALDI-TOF/TOF-MS. Identification of 117 differentially accumulated protein spots representing 82 unique proteins and five main expression patterns enabled a chronological description of wheat grain formation. Significant proteome expression differences between the two cultivars were found; these included 14 protein spots that accumulated in both cultivars but with different patterns and 27 cultivar-different spots. Among the cultivar-different protein spots, 14 accumulated in higher abundance in Jimai 20 than in Zhoumai 16, and included NAD-dependent isocitrate dehydrogenase, triticin precursor, LMW-s glutenin subunit and replication factor C-like protein. These proteins are likely to be associated with superior gluten quality. In addition, some proteins such as class II chitinase and peroxidase 1 with isoforms in developing grains were shown to be phosphorylated by Pro-Q Diamond staining and phosphorprotein site prediction. Phosphorylation could have important roles in wheat grain development. qRT-PCR analysis demonstrated that transcriptional and translational expression patterns of many genes were significantly different.Wheat grain proteins displayed variable expression patterns at different developmental stages and a considerable number of protein spots showed differential accumulation between two cultivars. Differences in seed storage proteins were considered to be related to different quality performance of the flour from these wheat cultivars. Some proteins with isoforms were phosphorylated, and this may reflect their importance in grain development. Our results provide new insights into proteome characterization during grain development in different wheat genotypes.Wheat is one of the three most important crops in the world due to its value as a major food source and its unique suit
GENETIC DIVERSITY OF WINTER BREAD WHEAT (TRITICUM AESTIVUM L. SSP. VULGARE)
Sonja Petrovi?
Poljoprivreda (Osijek) , 2011,
Abstract: Diversity was analyzed based on agronomic and morphologic traits and molecular data. The main objectives of this study were: 1. to estimate genetic diversity of wheat germplasm using agronomic and morphologic traits and molecular markers, 2. to investigate the existence of genetic erosion within tested wheat germplasm, 3. to explore potential utilization of combination of agronomic, morphologic and molecular markers in plant breeding. Forty winter bread wheat varieties were used originating from Croatia, Austria, France, Italy and Russia. Field trial was conducted during two vegetation years (2007/2008, 2008/2009) in three replications according to randomized block design. Ten traits were included in agronomic and morphologic analysis. Composition of high molecular weight glutenin subunits (HMW GS) was evaluated for 16 varieties, whereas literature data are used for the rest. Starch composition analysis was based on amylose and amylopectin isolation, their quantity and ratio. For the SSR analysis 26 microsatellite primers were used, and for the AFLP analysis four primer combinations. Statistical analysis was performed using SAS Software 9.1.3, NTSYS ver.2.2., Arlequin ver2.0. and Powermarker ver.3.25. Analyzed varieties displayed highly significant differences (p<0,001) for all agronomic traits and for amylose/amylopectin ratio. High variability of HMW GS was found among varieties. Estimation of genetic diversity based on morphologic and molecular data were used to construct dendograms. AMOVA was used to evaluate variability based on molecular data. Genetic diversity was estimated among and within morphologic and molecular data. SSR and AFLP markers showed efficient discrimination power between highly related genotypes. Significant correlation was found out between two molecular methods which showed more accurate estimate of genetic diversity than by agronomic and morphologic data.
Bread Wheat (Triticum aestivum L.) Productivity and Profitability as Affected by Method of Sowing and Seeding Rate Under Qena Environment  [PDF]
E.A. Abd El-Lattief
Asian Journal of Crop Science , 2011,
Abstract: Sowing methods and seeding rate play an important role in the placement of seed at proper depth and stand establishment of the growing crop which ultimately affects crop growth and productivity. This study was conducted for 2 seasons to establish optimal sowing method and seeding rate for bread wheat (Triticum aestivum L.) in sandy-loam soil. The study aimed at achieving high yield and profit. A field experiment was conducted using a randomized complete block in split plot design with three planting techniques (hilling in ridges, drilling in rows and broadcasting) and four seeding rates (100, 125, 150 and 175 kg ha-1) as the main plot and split plot, respectively. Results revealed that all yield and yield parameters were significantly affected by the sowing method and seed rate, while grain protein content was non-significant by these factors. The interaction of sowing method and seed rate significantly affected the number of effective tillers m-2, weight of grains spike-1, grain and straw yields ha-1 and harvest index. Wheat sown by drilling method at the seed rate 150 kg ha-1 gave the highest values of grain and straw yields ha-1 and harvest index and this treatment was found to be most economical. Based on these results, it is recommended to sow 150 kg ha-1 seeds by using drill method for planting bread wheat Giza 168 cv under similar soil and climatic conditions. Correlation coefficients analyses revealed positive significant relationships between grain yield and plant height, effective tillers m-2, grain number spike-1, straw yield and harvest index.
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