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Genetic diversity among 45 Indian mustard ( Brassica juncea L.) genotypes comprising 37 germplasm collections, five advance breeding lines and three improved cultivars was investigated at the DNA level using the random amplified polymorphic DNA (RAPD) technique. Fifteen primers used generated a total of 92 RAPD fragments, of which 81 (88%) were polymorphic. Of these, 13 were unique to accession ‘Pak85559’. Each primer produced four to nine amplified products with an average of 6.13 bands per primer. Based on pairwise comparisons of RAPD amplification products, Nei and Li's similarity coefficients were calculated to evaluate the relationships among the accessions. Pairwise similarity indices were higher among the oilseed accessions and cultivars showing narrow ranges of 0.77–0.99. An unweighted pair-group method with arithmetic averages cluster analysis based on these genetic similarities placed most of the collections and oilseed cultivars close to each other, showing a low level of polymorphism between the accessions used. However, the clusters formed by oilseed collections and cultivars were comparatively distinct from that of advanced breeding lines. Genetically, all of the accessions were classified into a few major groups and a number of individual accessions. Advanced breeding lines were relatively divergent from the rest of the accessions and formed independent clusters. Clustering of the accessions did not show any pattern of association between the RAPD markers and the collection sites. A low level of genetic variability of oilseed mustard was attributed to the selection for similar traits and horticultural uses. Perhaps close parentage of these accessions further contributed towards their little diversity. The study demonstrated that RAPD is a simple and fast technique to compare the genetic relationship and pattern of variation among the gene pool of this crop. [ABSTRACT FROM AUTHOR]

Salt stress is one of the key abiotic stresses that affect both the qualitative and quantitative characters of many Brassica rapa sub-species by disturbing its normal morphobiochemical processes. Therefore, the present research work was designed to study the effect of different NaCl events (0, 50,100 and 150 mmol) on morphological and biochemical characters and to screen salt tolerant genotypes among brown, yellow and toria types of B. rapa sub-species. The plants were grown in test tubes with addition of four level of NaCl (0, 50,100 and 150 mmol). The effect of salinity on shoot and root length, shoot/ root fresh and dry weight, relative water content (RWC), proline and chlorophyll a, b, a+b contents was recorded after 4 weeks of sowing. The genotype 22861 (brown type) showed excellent morphological and biochemical performance at all stress levels followed by Toria-Sathi and Toria-A respectively as compared to Check variety TS-1. The genotype 26158 (yellow type) gave very poor performance and retard growth. The %RWC values and chlorophyll a, b and a+b contents were decreased several folds with the increase of salt concentration. While, the proline contents was increased with raising of salt stress. The brown and toria types showed maximum tolerance to salt stress at early germination stages as compare to yellows one. The present study will serve as model to develop quick salt tolerant genotypes among different plant sub-species against salt stress. [ABSTRACT FROM AUTHOR]

Developing high yielding safflower cultivars with good adaptation to diverse environmental conditions can improve production in terms of seed yield and reduce the deficiency in edible oil. The genetic variability that exists among and within populations for desirable agronomic traits can be used to develop elite cultivars. A total of 94 safflower accessions from 26 different countries were used in this study to evaluate morphoagronomic performance, determine the pattern of similarity centers, and identify the best performing accessions by conducting 2 field experiments in Pakistan and Turkey using augmented design. Genetic diversity for important yield and yield traits was described including capitulum diameter (17.30 to 28.30 mm), branches per plant (5.10 to 17.30), capitula per plant (8.70 to 80.40), and seed yield per plant (4.86 to 51.02 g). These analyses showed a good level of variation in the current study. Using principal component analysis, it was observed that days to flower initiation, days to 50% flowering, days to flower completion, seed yield per plant, capitula per plant, branches per plant, seeds per capitulum, and capitulum diameter were the major contributors to the observed genetic variability in the evaluated safflower panel. Seed yield per plant reflected a significant and positive correlation with capitula per plant, branches per plant, and capitulum diameter, and these traits can be suggested as a selection criterion in safflower breeding programs. The hierarchical clustering was in agreement with the patterns of 7 similarity centers based on seed yield per plant, capitula per plant, capitulum diameter, and branches per plant. During this study, a few promising safflower accessions were selected for future breeding programs. [ABSTRACT FROM AUTHOR]

The 96 genotypes of Trigonella foenum-graecum L. (Fenugreek) were estimated by using Sodium Dodecyl Sulphate Poly Acrylamide Gel Electrophoresis (SDS-PAGE). The accessions were maintained from diverse ecological areas of the world. Total seed storage proteins were electrophoresis on 12.5% polyacrylamide gels. A total of 17 protein bands were detected, of which seven were highly polymorphic and six were moderate polymorphic and four were low polymorphic with molecular weight extending from of ~15 to ~180 kDa . The dendrogram based on similarity matrix using Unweighted Pair Group Method with Arithmetic Mean (UPGMA) divided all the genotypes into four major clusters i.e., I, II, III and IV comprising 51, 24, 10 and 11 accessions, respectively. Although limited genetic diversity was detected amongst known germplasm but the presence/absence of polymorphic bands revealed a significant variances among different Trigonella genotypes. The differences exposed in this project work should be oppressed for the future breeding prospective of Trigonella genotypes by using other advanced molecular techniques. The SDS-PAGE per se seems inadequate tool for such kind of analysis, and may be integrated with other genetic and sequence based approaches for more precise estimation of the genetic variability within closely related accessions. Our results provide baseline for obtaining locally adapted and improved cultivars of fenugreek in Pakistan. [ABSTRACT FROM AUTHOR]

Genetic diversity was studied in 39 indigenous Brassica juncea accessions along with a check for 10 morphological and 4 biochemical traits under field conditions by cluster and principal component analyses. Each accession was sown in 2 rows of 4 meter length. Row to row and plant to plant spacing was kept at 45 and 10 cm respectively. Cluster analysis divided the total 39 accessions into five and seven major groups during 2007 and 2008, respectively. Data based on first and second five PCs with > 1 contributed 73.30% and 64.45% of the variability amongst accessions, respectively. Scatter plot and tree diagrams demonstrated sufficient diversity among the Brassica juncea accessions for various morphological and biochemical traits and some extent of association between different clusters. The results concluded that morpho -biochemical diversity in the studied material is structured by genotypes and this diversity could be utilized for future cu ltivar breeding and germplasm conservation programs. [ABSTRACT FROM AUTHOR]

Being predominant protein of maize seed, its nutritional quality is dependent on composition of zein polypeptides. The major storage protein of maize seed is alcohol soluble zein, which accounts for more than 50% of total seed storage protein. The variation of zein fraction of seed storage protein in maize genetic resources was assessed by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). Variation in terms of absence and presence, intensity and molecular size was observed in zein polypeptides. On the basis of variation in banding patterns of zein polypeptides, the maize genetic resources were classified into five variation groups which highlight the wide variation in zein polypeptides among maize genetic resources. The group 2 exhibited high accumulation of 70 and 60 kDa zein polypeptides and group 3 exhibited high accumulation of 25 and 20 kDa zein polypeptides as compared to group 1, 4 and 5.These maize genetic resources might have significant implications for nutritional quality improvement of maize.© 2014 Friends Science Publishers [ABSTRACT FROM AUTHOR]

Genetic diversity was assessed among 32 advanced wheat breeding lines included in the National Uniform Wheat Yield Trials (2006-07) of Pakistan using molecular (DNA) and biochemical (SDS-PAGE) markers. Of the 72 RAPD primers used for initial screening, 15 were found polymorphic. A total of 140 bands (61.4% polymorphic) were generated by the 15 random decamer primers. Genetic similarity coefficients ranged from 0.81 to 0.94 for rainfed and from 0.70 to 0.93 for the normal seeding date group. Cluster analysis using the unweighted pair group method of arithmetic averages (UPGMA) clustered the 32 advanced wheat breeding lines into one major and three small groups. Maximum level of polymorphism (90%) was observed for the primer OPA-05. Lines N9 and N11 showed the least genetic similarities (0.70-0.82 and 0.71-0.83, respectively) with rest of the lines studied. Line RF1 had the maximum similarity (0.81-0.94) with other lines. Wheat lines included in the normal seeding date were relatively distantly related than those in the rainfed group. Seed storage protein analysis produced 19 subunits ranging from 29-120KDa. Similarity coefficients ranged from 0.53 to 1.0 for the normal seeding date and from 0.47 to 1.0 for the rainfed group. High molecular weight subunits (particularly 120KDa) showed greater polymorphism than the lower molecular weight subunits. Narrow genetic base was observed in wheat lines included in the rainfed group. DNA fingerprinting of advanced breeding lines may help to avoid release of varieties with narrow genetic base in the future. [ABSTRACT FROM AUTHOR]