The Influence of Dissimilarity of Comparables on the Correctness of Estimation in the Comparative Approach Procedure

The subject of this article is the still relevant issue of the adequate choice of comparables in evaluation procedures within the sales comparison approach. The text features the results of an experiment that makes it possible to validate the dependence of the accuracy of the final estimation of the price of valued objects in relation to the criteria of significance of similarity as a determinant of accepting individual objects as sufficiently similar, and the dissimilarity coefficients describing the created reference sets. Based on the example of simulated data, it has been shown that there is a clear relationship between the accuracy of the estimates made and the selection of comparables. In a set of all possible calculation variations, estimations based on selected data are characterized by more accurate calculations relative to parallel calculations carried out on the widest possible sets of comparables.

Towards a unifying framework for diversity and dissimilarity coefficients

Diversity and dissimilarity within and between species assemblages have now been studied for more than half a century by community ecologists in relation to their connections with ecosystem functioning. However, a generalized framework that puts diversity and dissimilarity coefficients under the same formal umbrella is still lacking. In this paper, we show that generalized means represent an effective tool to develop a unifying formulation for the construction of a large array of parametric diversity and dissimilarity measures. These measures include some of the classical diversity coefficients, such as the Shannon entropy, the Gini-Simpson index or the parametric diversity of Patil and Taillie, together with a large number of dissimilarity coefficients of the Bray-Curtis family and can be further extended to the measurement of functional and phylogenetic differences within and between plots.

Assessment of Genetic Diversity among Indian and Exotic Genotypes of Brassica juncea using Phenotypic Evaluation

Background: Rapeseed-mustard is one of the most important oilseed crops in India, however, its genetic diversity is barely known. A better understanding on this topic is essential for the proper utilization of genotypes in crop improvement. Methods: Present study was carried out to determine the genetic diversity among 95 diverse genotypes of Brassica juncea (L.) in paired rows of 4 m length with a spacing of 30 x 10-15 cm (row × plant). Data were recorded on 11 different agro-morphological characters. Result: All the 95 genotypes were grouped into five distinct clusters based on Manhattan dissimilarity coefficients. Amongst the five clusters, cluster V and IV had the maximum number of genotypes (35 and 23 genotypes respectively) and cluster II with least number of genotypes (three). The Manhattan dissimilarity coefficients ranged from 0.741 to 8.299. Based on the genetic dissimilarity matrix, the maximum dissimilarity (8.299) was observed between the genotypes, DRMRIJ-15-133 and M 62. Cluster III recorded for medium plant height with medium early maturity and cluster I, had maximum mean values for most of the agro-morphological traits. The present work indicated the presence of high genetic diversity among genotypes, which can be used in future breeding programmes for developing mustard cultivars and germplasm management purposes.

Genetic variability of popping quality traits and microsatellite-based characterization of popcorn inbreds for utilization in breeding programme

Popcorn is a popular snack item worldwide. The genetic base of popcorn germplasm is quite narrow, which resulted in limited number of popcorn hybrids. Here, a set of sub-tropically adapted 39 popcorn inbreds of exotic- and indigenous-origin, were characterized using morphological traits and molecular markers for their effective utilization in hybrid breeding. Significant variation for grain popping percentage (GPP: 86.0-98.0%), percent popping expansion (PPE: 1493-3213%) and volume after popping (VAP: 210-315ml) was observed. The mean PPE (2069%) and GPP (93.6%) among popcorn inbreds were higher than the popcorn check variety, VL popcorn (PPE: 1739%, GPP: 92%). Positive correlations were observed among GPP, PPE and VAP. Molecular characterization using 72 SSRs produced 237 alleles with a mean of 3.3 alleles per locus. Polymorphism information content ranged from 0.05 to 0.68, while Jaccard’s dissimilarity coefficients varied from 0.27-0.82. Principal coordinate analysis also depicted diverse genetic nature of inbreds. Cluster analysis grouped the inbreds into three major clusters each having 16, 18 and 5 inbreds. Contrasting inbreds were identified for development of mapping populations to identify loci governing desirable popping quality. The study also identified potential heterotic combinations. The information generated here assumes great significance in breeding for popcorn hybrids.

Morphological, cytological, and molecular variations induced by gamma rays in ground-grown chrysanthemum ‘Pinkling’

In this study, we analyzed the morphological, cytological, and molecular changes induced by different doses of 60Co-γ radiation on root cuttings of the ground-grown chrysanthemum ‘Pinkling’ plants whose survival and height were decreased with increasing radiation dose. A variety of mutants were observed among irradiated ‘Pinkling’ plants; floral mutations included alteration of floral types, term ligulate floret number, capitulum diameter, and floral colour. Meiotic observation of mutants showed that the frequency of chromosome aberrations increased with radiation dose. The mutants were further analyzed using ISSR markers and on the basis of polymorphic DNA banding patterns, floral mutants were genotypically distinguished. Eighteen polymorphic ISSR primers produced 110 scorable bands, of which 93 (84.5%) were polymorphic. The percentage of polymorphism ranged from 60% to 100%. Jaccard’s dissimilarity coefficients varied from 0.337 to 1.000, which attested to the high genetic variability induced by irradiation. It is concluded that gamma ray irradiation induces a sufficient frequency of mutations and that ISSR analysis may offer a useful molecular marker for the detection of mutants in chrysanthemum. The present findings provide valuable information for future breeding of ‘Pinkling’.

Genetic Diversity Analysis in Grasspea (Lathyrus sativus L.) Using SSR Molecular Markers

The study of genetic diversity among Lathyrus sativus L. may give fundamental insights into extent of genetic variation and provide options to meet the climate change challenge. 20 SSR loci were employed to assess the genetic diversity of 32 grasspea genotypes. Eleven markers proved to be polymorphic across examined genotypes in aggregation to allow detection of a total of 21 alleles with an average of 1.91 alleles per locus. The polymorphism information content (PIC) calculated as a relative measure of informativeness for each of the SSR markers, ranged from 0.11 to 0.34. The dendrogram from the neighbour-joining UPGMA cluster analysis of the pair-wise simple matching dissimilarity coefficients matrix grouped genotypes into three main clusters. Therefore the characters contributing maximum to genetic diversity may be given importance during grasspea hybridization program and these genotypes may be utilized in further grasspea breeding program aimed to enhance grain yield.