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maize single cross hybrid performance anda genetic distances (GD) computed from AFLP and SSR markers. Euphytica, 130(1): 87–99. Souza A.P. Relationship of intra-and interpopulation

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Abstract  

The UNESCO International Comparative Study on the Organization and Performance of Research Unists (ICSOPRU) has entered the period of drawing the theoretical and methodological conclusions from and starting the practical application of its results.Based on the experience of the 3 rounds of ICSOPRU, the national team of the Ukrainian SSR has attempted to broaden the scope and methodology of this international project. The main features of our studies are as follows.1.  The comparative analysis is performed among research units working or intending to work on common research topics. 2.  The complex characteristics determining the level of competence of the research units in achieving their research aims is evaluated by criteria specific to the given problems. 3.  In order to gain the above mentioned results, certain additional material had been included into The National Addendum and the national part of External Evaluations Questionnaire. Some additional software had also been developed.1–3 This paper concentrates on some methodological aspects of this approach and refers also to some problems of more intensive use of science and technology.

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Cereal Research Communications
Authors: N. Sinha, V. Priyanka, K.T. Ramya, T. Leena, J.A. Bhat, Harikrishna, N. Jain, P.K. Singh, G.P. Singh, and K.V. Prabhu

Abiotic stresses are major constraints to wheat productivity in many parts of the world. Tolerance to abiotic stresses can be achieved indirectly by selection for morpho-physiological traits. Physiological trait based breeding has been associated with improved performance under stress; and hence can combat and adapt wheat to drought and heat stress. Therefore, in the present study, phenotyping was carried out for agro-physiological traits in 52 diverse wheat germplasm lines under timely sown, rainfed and late sown environments for two years. Mean yield of the genotypes over the six environments were positively correlated with NDVI, days to maturity and negatively correlated with canopy temperature. The phenotypic data validated marker-trait associations of a number of meta-QTLs identified earlier for different physiological and agronomic traits. Six and seven meta-QTL genomic regions were found to be consistent in their expression for two years under rainfed/restricted irrigation and late sown environments, respectively. Expression analysis of the underlying candidate gene AK248593.1 in meta-QTL26 region revealed two folds higher expression in the NILs carrying the co-localized SSR markers. The linked markers of the thirteen meta-QTL regions associated with different traits can be used for effective transfer of the QTLs through marker assisted selection in wheat breeding programmes.

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Acta Agronomica Hungarica
Authors: A. A. Belousov, V. M. Sokolo, Y. M. Sivolap, V. P. Domenjuk, and N. J. Storcheus

The performance of maize hybrids developed on the basis of recombined inbred lines (RIL) selected from an F2 hybrid population using marker-assisted selection (MAS) was studied. The task was to estimate the efficiency of DNA marker technology for intrapopulation selection and to study the performance of hybrids produced from marker-derived inbreds of the F2 population (GK 26 × Mo 17). Two hundred RILs of marker origin were crossed with 3 unrelated testcross lines from the Lacaune, Mindszentpuszta and Reid heterotic groups. An effective marker test system and informative marker criteria were elaborated for increasing MAS effectiveness. A two-locus system on the basis of linked SSR markers proved to be the most effective. The genetic improvement effect (ΔG) of the C1 population for plant productivity, plant height and grain length ranged from 9.1 to 16.1%, depending on the phenotypic trait and h2 level. The best hybrids developed on the basis of RILs of marker origin outyielded the national check for grain yield by 6.8-7.6%.

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Genetic variation in the flint maize (Zea mays L. conv. indurata) gene pool has decreased significantly since the introduction of hybrid breeding into Europe in the 1950s, leading to greater genetic vulnerability. Landraces, stored in gene banks, offer a valuable source to broaden the genetic basis again. The objective of this study was the genetic characterization of 166 Swiss landrace accessions originating from 7 Swiss regions (alpine valleys). The material was fingerprinted using a set of ten SSRs (Simple Sequence Repeat Markers). The resulting cladogram showed three main clusters comprising 95, 22 and 49 accessions, respectively. The largest group of accessions, from the Rhine valley of St. Gallen (RT), was present in all three main clusters. However, the majority of RT accessions was found in the first main cluster, together with those from the western neighbouring region (Linthtal) and from the southwestern neighbouring region (Wallis). Those from Tessin (southern Switzerland) were found mainly in one sub-cluster within the third main cluster. This is a very encouraging first step in appraising the genetic differences among accessions from Swiss regions.

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Cereal Research Communications
Authors: Zhengqiang Ma, Shulin Xue, Feng Lin, Shaohua Yang, Guoqiang Li, Mingzhi Tang, Zhongxin Kong, Yong Cao, Dongmei Zhao, Haiyan Jia, Zhengzhi Zhang, and Lixia Zhang

Wangshuibai is an indigenous scab resistance germplasm originated from Jiangsu, China. To characterize the genetic basis of scab resistance in this germplasm, QTLs for type I and type II resistances were detected using a recombinant inbred line (RIL) population created by single seed descent from Nanda2419 × Wangshuibai and a molecular marker map of more than 4000 cM constructed using RAPD, SSR and STS markers. The major QTLs for type I resistance in Wangshuibai were mapped to chromosomes 4BL and 5AS, and those for type II resistance were mapped to chromosomes 3BS. In addition, a QTL on chromosome 2B showed association with both types of resistance. These QTLs were verified with QTL nearisogenic lines. We found, by mapping QTLs for agronomical traits in the same population, that on chromosomes 4BL and 5AS the scab resistance QTLs co-located with QTLs for plant height, thousand grain weight or flag leaf width. However, these associations could be break down by recombinant selection. We concluded that Wangshuibai is a valuable scab resistance gene resources and marker assisted selection would be of great help for its better utilization.

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Cereal Research Communications
Authors: L.R. Vemireddy, N. Ranjithkumar, A. Vipparla, M. Surapaneni, G. Choudhary, K.V. Sudhakarrao, and E.A. Siddiq

India bred high yielding rice varieties have enriched to a great extent the global rice germplasm since the mid-sixties. Systematic research efforts for development of cultivar-specific DNA fingerprints of major Indian rice cultivars, however, have not received due attention. The present investigation was aimed at development of DNA fingerprints for 90 high yielding rice varieties using hypervariable microsatellite (hvRM) markers. A panel of eight markers, viz. RM11313, RM13584, RM15004, RM5844, RM22250, RM22565, RM24260 and RM8207 was chosen from 52 polymorphic markers based on their highly polymorphic nature, SSR repeat type and number and ability to distinguish genotypes, in order to develop DNA fingerprints of 90 varieties. The remaining high polymorphic hvRM markers could be of immense value in future to distinguish new cultivars, in case they could not be distinguished by the 8 marker panel. Four of the 8 markers, viz. RM22250, RM13584, RM24260 and RM5844 were located in expressed genes and could be of value in DUS (Distinctness, Uniformity and Stability) testing. Thus we suggested, that this set of 8 loci could be used as standard for DNA fingerprinting of Indian rice cultivars.

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Thinopyrum ponticum (2n = 10x = 70) has donated rust resistance genes to protect wheat from this fungal disease. In the present study, the line ES-7, derived from the progeny of the crosses between common wheat cultivar Abbondanza and Triticum aestivumTh. ponticum partial amphiploid line Xiaoyan784, was characterized by cytological, fluorescence in situ hybridization (FISH), genomic in situ hybridization (GISH) and EST-STS marker techniques. Cytological observations revealed that the configuration of ES-7 was 2n = 42 = 21 II. GISH and FISH results showed that ES-7 had two St chromosomes and lacked 5A chromosomes compared to common wheat. The 4A chromosome of ES-7 had small alterations from common wheat. Two EST-SSR markers BE482522 and BG262826, specific to Th. ponticum and tetraploid Pseudoroegneria spicata (2n = 4x = 28), locate on the homoeologous group 5 chromosomes of wheat, could amplify polymorphic bands in ES-7. It was suggested that the introduced St chromosomes belonged to homoeologous group 5, that is, ES-7 was a 5St (5A) disomic substitution line. Furthermore, ES-7 showed highly resistance to mixed stripe rust races of CYR32 and CYR33 in adult stages, which was possibly inherited from Th. ponticum. Thus, ES-7 can be used for wheat stripe rust resistance breeding program.

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It is well established that the ingestion of cereal prolamins, such as gluten, causes the characteristic symptoms of celiac disease (CD) in people predisposed to it. DNA-based PCR method provides new ways to detect gluten in processed foodstuffs, such as bread. The aim of this work was to adapt a new primer pair combination and to initiate a carefully elaborated PCR methodology to experiment with DNA-based analysis. At first, the purity of cleaned DNA was verified using B49317 and A49855 chloroplast DNA primer pair. Then TR01/2 wheat specific PCR primer pair was used for checking the origin of the DNA, and P1/2 microsatellite (SSR) adapted primer pair for detecting allergen (gluten) specific residues. Method optimisation was achieved with cereal flour samples, then bread and dry pasta products from wheat were used, which were analysed as heat-treated samples with three primer pairs. The gluten specific primer pair was tested on cross-reactive cereals such as rye, barley, triticale and on some questionable cereals, such as oat, and pseudo-cereals, e.g. buck wheat and amaranth.

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Diploid wheat T. monococcum L. is a model plant for wheat functional genomics. A soft glume mutant was identified during manual screening of EMS-treated M2 progenies of a T. monococcum accession pau14087. The seeds in the mature spike of the mutant could be easily threshed manually. The soft glume mutant with high sterility, tapering and broader spikes had also tougher rachis than the wild type parent. Genetic analysis of crosses of the mutant with wild type indicated that the mutant was monogenic recessive. To map the soft glume mutant, a mapping population was developed by crossing the soft glume mutant with wild Triticum boeoticum acc. pau 5088, having tough glumes and hard threshing. The soft glume mutant was mapped between SSR markers Xgwm473 and Xbarc69 on 7AmL chromosome of T. monococcum, with a genetic distance of 1.8 cM and 8.3 cM, respectively. The soft glum mutant mapped on 7AmL, being distinct from a previously mapped soft glume mutant in wheat, has been designated as sog2. The work on fine mapping of sog2 gene is in progress.

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