Authors:Andrei Stefan, Craita M. Rosu, Catalina Stedel, Lucian D. Gorgan, and Rodica C. Efrose
The application of commercial rhizobial inoculants to legume crops is proving to be an alternative to synthetic fertilizer use. The challenge for sustainable agriculture resides in the compatibility between crop, inoculants and environmental conditions. The evaluation of symbiotic efficiency and genetic diversity of indigenous rhizobial strains could lead to the development of better inoculants and increased crop production. The genetic variability of 32 wild indigenous rhizobial isolates was assessed by RAPD (Random Amplified Polymorphic DNA). The strains were isolated from red clover (Trifolium pratense L.) nodules from two distinct geographical regions of Northern and Eastern Romania. Three decamer primers were used to resolve the phylogenetic relationships between the investigated isolates. Cluster analysis revealed a high diversity; most strains clustered together based on their geographical location.
Genetic variability and correlation analysis were studied in 20 accessions of ‘egusi’ melon during two growing seasons. The genotypic correlation coefficients with seed yield were partitioned into direct and indirect effect causes. Heritability in the broad sense ranged from 17% for fruit circumference to 90% for days to germination and flowering in the early season, while in the late season, heritability ranged from 7% for seed weight per fruit to 88% for days to germination. High phenotypic and genotypic coefficients of variation were recorded for seed yield while days to maturity had the lowest in both seasons. Fruit circumference and fruit weight had significant genotypic and phenotypic correlation with seed yield in the early season, while number of branches per plant, vine length per plant, number of fruits per plant and fruit circumference per plant showed significant genotypic and phenotypic correlation with seed yield in the late season. Environmental correlation coefficients were significant between seed yield and vine length per plant, number of fruits per plant and fruit size per plant. Vine length per plant and fruit circumference per plant had the largest positive direct effect on seed yield. Knowledge of the relationship of these characters with seed yield will aid in the selection of genotypes that have high seed yield, which will also be specific to the two major seasons in the year.
Authors:T. Vyhnánek, E. Nevrtalová, and K. Slezáková
The variability of microsatellite markers of 16 genotypes of triticale (×
Wittmack, 2n = 6x = 42, BBAARR) was studied. Five varieties from Poland (Gutek, Kitaro, Lamberto, Presto and Tornado), three from Germany (Lupus, Ticino and Triamant), one from Russia (Valentin-90) and seven translocation forms derived from cv. Presto (donors of good bread-making quality) were analysed. SSR markers localised on chromosomes of the A, B, D and R genomes were chosen from literature for analysis. Based on 48 SSR markers (27 wheat and 21 rye SSR markers) a dendrogram was calculated, which highly significantly differentiated the Valentine-90 genotype from all the other 15 genotypes split into three sub-clusters. The first one includes the cv. Gutek, Tornado, Presto and translocation forms of cv. Presto. The second sub-cluster consists of the cv. Kitaro, Lamberto, Ticino and Triamant. The third sub-cluster cluster consists of the cv. Lupus only. The diversity index (DI), the probabilities of identity (PI) and the polymorphic information content (PIC) of SSR markers were calculated. We detected 184 alleles from 48 markers with an average of 3.83 alleles per locus (ranging from 1 to 9 alleles per locus). The average polymorphic information content was 0.48 ranging between 0.00 and 0.85.
Authors:H. Rahman, N. Murtaza, K. Shah, A. Qayyum, I. Ullah, and W. Malik
Radin, J. W., Lu, Z., Percy, R. G., Zeiger, E. (1994): Geneticvariability for stomatal conductance in Pima cotton and its relation to improvements of heat adaptation.
Proc. Natl. Acad. Sci.
Authors:Ervin Albert, Rita Sipos, Szilárd Jánosi, Péter Kovács, Árpád Kenéz, Adrienn Micsinai, Zsófia Noszály, and Imre Biksi
., 2014; Cortimiglia et al., 2016; Parisi et al., 2016 ). Materials and methods Origin of isolates To investigate the geneticvariability of MRSA isolates from milk from the past 15 years, conserved MRSA strains of the Veterinary Diagnostic Directorate
Authors:Ivan Toplak, Sava Lazić, Diana Lupulović, Jasna Prodanov-Radulović, Zsolt Becskei, Radoslav Došen, and Tamaš Petrović
Recent variants of porcine circovirus type 2 (PCV2) were obtained from tissues of domestic pigs with porcine circovirus associated disease and from randomly selected wild boar samples from Serbia and Slovenia. A 450-base-pair nucleotide sequence was obtained by PCR from the ORF2. The derived nucleotide and amino acid sequences were aligned and compared to the corresponding region of closely related PCV2 sequences determined in previous years and retrieved from the GenBank. The 30 Serbian and 17 Slovenian PCV2 sequences clustered into three previously determined genotypes (PCV2a: 7), (PCV2b: 38) and (PCV2d: 2). Three major variable regions, concerning 29 amino acid position substitutions within the ORF2, were observed, which further supports the segregation of the detected strains into three separate genotypes. This study indicates that PCV2b is the predominant genotype in Serbia and Slovenia and the detected PCV2 strains are closely related to those previously described in Europe and in other parts of the world.
Authors:L. Amallah, M. Taghouti, K. Rhrib, F. Gaboun, and R. Hassikou
Durum wheat landraces are still cultivated to take advantage of their excellent grain and straw quality, adaptation to abiotic stresses, and extremely wide variety of uses. The safeguarding and rehabilitation of genetic inheritance requires genetic characterization and evaluation. In this study, forty durum wheat landraces originating from Mediterranean countries were evaluated according to agro-morphological and technological properties. We show that the germplasm was highly variable. The mean yellow pigment and protein content was higher in landraces (15.58%; 7.32 ppm) than in the Moroccan cultivars used as controls (14.6%; 5.48 ppm). In addition, principal component analysis identified five groups showing variable agronomic and qualitative characteristics that might be useful in the rational design of breeding programs.