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.
Aegiolops kotschyi cytoplasmic male sterile system often results in part of haploid plants in wheat (Triticum aestivum L.). To elucidate the origin of haploid, 235 wheat microsatellite (SSR) primers were randomly selected and screened for polymorphism between haploid (2n = 3x = 21 ABD) and its parents, male-sterile line YM21 (2n = 6x = 42 AABBDD) and male fertile restorer YM2 (2n = 6x = 42 AABBDD). About 200 SSR markers yielded clear bands from denatured PAGE, of which 180 markers have identifiable amplification patterns, and 20 markers (around 8%) resulted in different amplification products between the haploid and the restorer, YM2. There were no SSR markers that were found to be distinguishable between the haploid and the male sterile line YM21. In addition, different distribution of HMW-GS between endosperm and seedlings from the same seeds further confirmed that the haploid genomes were inherited from the maternal parent. After haploidization, 1.7% and 0.91% of total sites were up- and down-regulated exceeding twofold in the shoot and the root of haploid, respectively, and most of the differentially expressed loci were up/down-regulated about twofold. Out of the sensitive loci in haploid, 94 loci in the shoot, 72 loci in the root can be classified into three functional subdivisions: biological process, cellular component and molecular function, respectively.
Authors:A. Kaushik, S. Jain, V. Bhankar, and R. Jain
Availability of markers that distinguish commercially important premium Basmati rice varieties from cheaper Basmati or non-Basmati indica rice varieties is of interest to exporters, commercial suppliers and consumers to ensure the varietal purity of Basmati rice supplies. In this study, a fingerprint database of 27 rice varieties including commercially important traditional Basmati (TB), cross-bred (evolved) Basmati and some non-Basmati indica rice varieties has been prepared using 50 microsatellite markers. A total of 271 electromorphs (alleles) were detected at 50 SSR (simple sequence repeat) loci, 92 of which were observed only in 2–10 of the 16 Basmati rice varieties. Notably, 7–10 of the sixteen Basmati rice varieties had the same Basmati specific electromorphs at RM562, RM551 and RM547 loci. Alarge number of unique (22) and null (16) electromorphs were noticed in Basmati rice varieties. A combination of four SSR markers (RM224, RM248, RM547 and RM594) can be used to differentiate all the 27 rice varieties. Specific SSR markers have been identified for the authentication of Premium Basmati rice cultivars such as Taraori Basmati (RM547, RM594 and RM511), Basmati 370 (RM252, RM426 and RM527), Karnal Local (RM248, RM423 and RM488) and Pusa 1121 (RM252, RM400 and RM410), and for the detection of adulterant like Sharbati (RM215, RM423 and RM259). SSR database reported here, shall broaden the list of SSR markers already recommended for varietal identification and detection of adulteration in Basmati rice supplies.
Grain Protein Content (GPC) of wheat is significant for enhanced nutritional value and is one of the most important aspects effecting pasta and bread making quality as well. Seventy seven Pakistani wheat varieties and advance lines were analysed to access the allelic distribution at microsatellite Xuhw89 locus using functional SSR marker. Overall, 42% of tested wheat genotypes were found to carry 126 + 130-bp allele while a 126-bp allele was detected in 58% of genotypes. A target band of 126-bp was amplified in all tested genotypes, however, an additional band of 130-bp was also detected along with 126-bp band in 32 genotypes. Genotypes i.e. (Punjab-96) total soluble protein and (MEXI PAK) globulin with 126 + 130-bp allele while (Faisalabad-2008) salt soluble protein and (TC-4928) albumin with allele of 126-bp depicted highest grain protein content. The alleles identification associated with maximum grain protein content in Pakistani wheat germplasm will assist in accelerating the breeding program in future.
Authors:A. Gémes Juhász, A. Stágel, S. Ács, L. Zatykó, and et al.
As locus-specific co-dominant PCR-based markers that allow semi-automated, high-throughput investigation technologies, microsatellites are ideal tools for genotype identification. Eleven of a set of 114 microsatellite markers available at the Agricultural Biotechnology Center proved to be suitable to distinguish between the parents of at least one of nine sweet pepper hybrid combinations. Markers with the highest information capacity were found to be capable of distinguishing between the parents of four different hybrid combinations and exhibited up to four different alleles in 18 haplotypes.
Authors:M. Golabadi, A. Arzani, and S. Mirmohammadi Maibody
Grain protein content (GPC) in durum wheat is a crucial determinant of pasta quality and as such is an important economic factor. This study was carried out to determine the microsatellite markers (SSRs) as associated with GPC in durum wheat grown under normal and moisture stress conditions. F3 and F4 population derived from 151 F2 individuals developed from a cross between Oste-Gata (drought tolerant) and Massara-1 (drought susceptible) genotypes, were used. The population was evaluated under four environmental conditions (two irrigation regimes in two growing seasons). The results of single marker regression analysis (SMA) revealed that 2, 4 and 10 markers to be associated with GPC, test weight (TW) and 1000 grain weight (TGW), respectively. These markers explained between 4.4 and 21.8% of the phenotypic variation in either environmental condition. The most significant marker observed for GPC was located on 5B chromosome near Xgwm408 under normal conditions and the other marker was observed on 1A, explaining about 15% of phenotypic variance. However, it was not recognized any marker related to GPC under drought stress conditions. Xgwm408 marker was coincident with the markers identified for TW, TGW and components of grain yield under drought stress conditions. In spite of 5B, the other chromosomes such as 2B and 3B were related to quantitative traits like TW and TGW. Composite interval mapping (CIM) identified 4 and 5 putative minor and major QTL for TW and TGW, respectively. Two QTL near Xbarc101 and Xbarc124 markers on 3B and 2B chromosome, explained up to 45.2 and 6% of phenotypic variations of TGW and TW, respectively.