Microsatellite Marker Based DNA Fingerprinting of Cotton (Gossypium Spp.) Hybrids and Their Parents

Cotton production in India by vast majority comes from cotton hybrids whose genetic purity is of great significance in seed production chain and trade. Therefore, there is need to develop a rapid, reliable and reproducible technique to assess the genetic purity of cotton hybrids as traditional, morphological traits-based ‘Grow-Out Test’ is resource intensive, time consuming, tedious and not an infallible procedure. In this regard, a study was planned to understand the genetic diversity among the hybrids and their parents, and also to identify SSR markers for confirmation of genetic purity or hybridity. One intra-arboreum hybrid, CICR2 (DS 5 GMS × LD 327 Sel.), four intra-hirsutum hybrids viz., CSHH198 (CSH 19 × CSH 8), CSHH238 (SH 2379 9Y × PIL 8 Sel.), CSHH243 (CSH 2013 × CSH 43), CSHH1862 (GMS 16A × CB 33) and one hirsutum × barbadense hybrid, Phule 388 (RHC-006 × RHCb-001) along with their respective parental lines were selected for molecular characterization. Of the total 215 SSR markers surveyed, 60 markers conveyed polymorphism. The information conveyed by the polymorphic SSR markers was utilized to assess the molecular divergence among the study material. Maximum genetic dissimilarity of 0.66 was noted between Phule 388 and LD 327 (Sel.), and between RHC-006 and DS 5 (GMS). Minimum genetic dissimilarity of 0.07 was observed between CSHH1862 with CB 33, followed by 0.11 between CICR2 with DS 5 (GMS). SSR markers were highly efficient in capturing both intra-species and inter-species level diversity. The clustering and factorial analysis was in congruence with the species of Gossypium. The diploid species genotypes were clustered separately and distinctly from the rest of the genotypes. All the hirsutum hybrids and their respective parents were found closely clustered. The inter-specific hybrid, Phule 388 along with its parents was found grouped closely. The genetic purity of the hybrids was confirmed using identified SSR markers [GH486, BNL1421, BNL3594, JESPR151 for G. hirsutum hybrid CSHH198; GH486, BNL2449, JESPR151, TMB0436 for G. hirsutum hybrid CSHH238; BNL2449, JESPR151, JESPR152 for G. hirsutum hybrid CSHH243; and, GH527, BNL3812, TMB1484, TMB1645, NAU1190, BNL3816 for inter-specific G. hirsutum × G. barbadense hybrid Phule 388]. The SSR markers were efficient in analysis of hybrid seed purity. The information generated in the present study about genetic diversity and genetic purity testing will greatly facilitate quality seed production of these cotton hybrids and thus, better cotton production.

Spatial and regional directory of tropical Auricularia mushrooms in Southwest, Nigeria

Bioremediation of wastelands and dumpsites in Africa is fast declining due to reduced mushroom populations. In the past, the forest of Africa was teaming with mushrooms, but nowadays; mushrooms are severely exploited, resulting in gradual drift to extinction. Mushrooms have the tendency to degrade recalcitrant wastes and absorb heavy metals (Bio-accumulation). Unless concerted efforts are made to rejuvenate or rescue the surviving mushroom population, Africa will one day be overshadowed by wastes. The mushroom diversity in Southwest, Nigeria was determined by both morphological and molecular markers, 14 primers (OPB-11, OPB-12, OPB-15, OPB-20, OPB-21, OPH-3, OPH-5, OPH-10, OPH-15, OPT-1, OPT-5, OPT-7, OPT-10 and OPT-19) produced polymorphism with the test samples under electrophoresis gel (PCR and RAPD). Using standard morphological markers, Auricularia auricula was found to be evenly distributed across 8 locations in Ekiti and Osun, 6 locations in Ogun, 5 locations in Oyo and 4 locations in Lagos. There was none identified in Ondo. Auricularia polytricha was found in abundance in all the locations in Ondo. Lagos only had 3 out of its outline Stations graced with the presence of A. polytricha, whereas, Ogun, Ekiti, Osun and Oyo had no records of A. polytricha. From the genetic dissimilarity chart, 6 clusters of mushroom, sub-characterized into 3 distinct species (Auricularia polytricha, A. auricula and an unrelated Auricularia outlier species) and 5 cultivars were obtained in the region of Southwest, Nigeria. The population of all the Auricularia mushrooms currently present in Southwest, Nigeria was effectively captioned (Location, type and identity) by this research.

PHÂN TÍCH ĐA DẠNG DI TRUYỀN GIỐNG ỚT XIÊM ĐỊA PHƯƠNG Ở QUẢNG NGÃI BẰNG CHỈ THỊ RAPD

Sự đa dạng di truyền của 15 mẫu giống ớt Xiêm địa phương của Quảng Ngãi và mối quan hệ giữa chúng với 5 giống ớt A Riêu và 5 giống ớt Bay đã được đánh giá dựa trên kết quả của 10 mồi RAPD. Hệ số tương đồng di truyền giữa 25 mẫu ớt dao động từ 0,56 đến 1,0. Hệ số tương đồng di truyền và sơ đồ về cây phát sinh loài đã phân ớt A Riêu của Quảng Nam và ớt Bay của Gia Lai thành các nhóm khác nhau. Ớt Xiêm của Quảng Nam thuộc vào cả 2 nhóm và việc phân chia ớt Xiêm vào các nhóm này có mối liên hệ mật thiết với hình dạng quả, Ớt Xiêm với dạng quả lớn thuộc cùng phân nhóm với ớt A Riêu, ớt Xiêm dạng quả nhỏ đến trung bình thuộc cùng phân nhóm với ớt Bay. ABSTRACT Genetic diversity of 15 Xiem chili accessions of Quang Ngai province and its relationship with 5 A Rieu chili accessions of Quang Nam and 5 Bay chili accessions of Gia Lai was assessed by using 10 PCR - RAPD primer. The genetic dissimilarity of the total of 25 accessions was ranged from 0,56 to 1,0. RAPD analysis combined with the construction of phylogenetic tree revealed that big Xiem accessions had the same cluster to A Rieu, while small to medium Xiem accessions had the same cluster to Bay.

Genetic divergence between half-sibling progenies of kale using different multivariate approaches

ABSTRACT The aim of this study was to evaluate the genetic dissimilarity between half-sibling progenies of kale in order to determine the most divergent progenies and, also, to select potential parents. Thirty-six kale genotypes were evaluated, being thirty-three half-sibling progenies and three commercial cultivars, in a randomized block design with four replicates and six plants per plot. Twenty-eight traits were evaluated in each plant per plot, thirteen quantitative and fifteen qualitative traits. Genetic divergence was studied using MANOVA and canonical variables for quantitative observations. In addition, dendrograms were made for quantitative, qualitative and joint analyses by UPGMA method, using Mahalanobis distance. Genetic divergence was observed between genotypes. Commercial cultivars were more divergent than half-sibling progenies. Among half-sibling progenies, the most divergent ones were P1, P21, P23, P25 and P30. We concluded that half-sibling progenies P1, P23 and P30 can be used as potential parents to compose the recombinant population.

Genetic dissimilarity, selection index and correlation estimation in a melon germplasm

ABSTRACT The success of breeding programs depends on genetic variability. Individuals selected based on a few traits may be a limitation. One alternative is the use of nonparametric indices. However, there is no information on the use of selection indices in melon germplasms. The present study aimed to estimate genetic dissimilarity in a melon germplasm and select potential parent plants for future breeding programs. The genetic material consisted of 37 melon accessions. The traits assessed were fruit diameter and length, diameter and length of the fruit cavity and total soluble solids. Genetic dissimilarity was assessed by multivariate analyses (UPGMA and Tocher). Selection gain estimates were analyzed by comparing the classic Smith-Hazel and sum of ranks indices. Genetic diversity was observed between accessions. The variable that contributed most to genetic dissimilarity was fruit cavity length. Simultaneous selection for the traits assessed based on the sum of ranks index is better suited to melon germplasm assessment. The best accessions for the five variables simultaneously were UFU07, UFU23, UFU09, UFU21, UFU28 and UFU30.

Genetic diversity of walnut (Juglans regia L.) seedlings through SSR markers in north-western Himalayan region of Jammu

screening of 25 SSR markers, revealed 23 clear and consistent amplification profiles in the entire walnut germplasm set. A total of 54 alleles were amplified by SSR primers and the number of alleles range from 2 to 3. The PIC value ranged from 0.36 to 0.68. The dendrogram classified all genotypes into two main clusters with various degrees of subclustering. Estimated genetic dissimilarity coefficient ranged from 0.36 to 0.85. Through model-based cluster analysis all genotypes were grouped into 5 genetically distinct subpopulations. The expected heterozygosity at a given locus was found to range from 0.520 to 0.5477. Similarly, population differentiation measurements (Fst) ranged from 0.2286 to 0.2909. These findings would be helpful for decision making in future walnut breeding studies, germplasm management activities to maximize genetic diversity in walnut germplasm and may also prove useful in future for conducting association mapping in walnut for different traits.

GENETIC DISSIMILARITY FOR RESISTANCE TO FOLIAR DISEASES ASSOCIATED WITH THE AGRONOMIC POTENTIAL IN MAIZE

ABSTRACT In the present study the objective was to evaluate the genetic diversity among families of maize siblings for resistance to foliar diseases associated with their agronomic potential, identifying groups of families that can be used as sources of resistance in maize crop. The experiments were conducted in the experimental area of the Federal University of Goiás at the Jataí Regional Unit, in Jataí, GO, Brazil, constituted by 182 half-sibling families of maize and two commercial hybrids as a control. The 182 half-sibling families were divided into three experiments with 60, 60 and 62 families, respectively. The experimental design used was randomized blocks, with three replicates. Eight quantitative characters and 4 foliar diseases were evaluated. The multivariate analysis technique was used to measure the genetic divergence for the four foliar diseases represented by the generalized Mahalanobis distance. Based on the genetic dissimilarity matrix, the dendrogram was constructed using the clustering method of the average distance between groups (Unweighted Pair Group Method with Arithmetic Mean - UPGMA). After defining the groups, univariate analysis of variance was performed in order to evaluate the effects of the groups on each character studied. Comparisons were made between the means of the groups, using the Tukey test (p <0.05). White spot (32.53%) was the disease that most contributed to the total divergence between families. Group 10 stood out among the others as a source of resistance to the disease complex associated with yield. The genetic variability of families for foliar disease complex reveals potential for future studies facing pyramiding genes.