Arunabh Joshi

Biosynthesised silver nanoparticles using aqueous leaf extract of Tagetes patula L. and evaluation of their antifungal activity against phytopathogenic fungi

In the recent decades, nanotechnology is gaining tremendous impetus due to its capability of modulating metals into their nanosize, which drastically changes the chemical, physical, biological and optical properties of metals. In this study, silver nanoparticles (AgNPs) synthesis using aqueous leaf extracts of Tagetes patula L. which act as reducing agent as well as capping agent is reported. Synthesis of AgNPs was observed at different parameters like temperature, concentration of silver nitrate, leaf extract concentration and time of reduction. The AgNPs were characterized using UV-vis spectroscopy, scanning electron microscope with energy dispersive spectroscopy, transmission electron microscopy with selected area electron diffraction, X-ray diffraction, Fourier transform infrared and dynamic light scattering analysis. These analyses revealed the size of nanoparticles ranging from 15 to 30 nm as well revealed their spherical shape and cubic and hexagonal lattice structure. The lower zeta potential (-14.2mV) and the FTIR spectra indicate that the synthesized AgNPs are remarkably stable for a long period due to the capped biomolecules on the surface of nanoparticles. Furthermore, these AgNPs were found to be highly toxic against phytopathogenic fungi Colletotrichum chlorophyti by both in vitro and in vivo and might be a safer alternative to chemical fungicides.

Estimate heterosis for latex yield and its related traits in opium poppy (Papaver somniferum L.)

Eight parents and their all possible crosses (Excluding reciprocals) of opium poppy were grown at experimental farm of Plant Breeding and Genetics, Rajasthan College of Agriculture, Maharana Pratap University of Agriculture and Technology, Udaipur (Rajasthan) in randomized block design with three replications and two environments and estimate heterosis for 11 yield and yield related traits. Analysis of variances indicated significant variability among parents and their hybrids for all the eleven characters studied. Significant parents vs hybrids contrast for all the characters except for plant height, peduncle length and diameter of main capsule in pooled over environments indicated the presence of heterosis for these characters. The experimental result for heterosis revealed that out of 28 hybrids, 16 hybrids recorded significant positive heterosis for latex yield per plant, nine and six hybrids recorded significant positive heterobeltiosis and economic heterosis for latex yield per plant, respectively. The crosses UOP-53 x UOP-1185, UOP-80 x UOP-20, UOP-79 x UOP-1185 and UOP-79 x UOP-20 showed the highest magnitude of heterosis and heterobeltiosis for latex yield per plant, seed yield per plant, husk yield per plant, days to 50% flowering and seed harvest index. The crosses UOP-79 x UOP-60 and UOP-80 x UOP-20 showed highest significant positive economic heterosis for latex yield per plant, seed yield per plant, husk yield per plant, effective capsules per plant, days to 50% flowering, morphine content and seed harvest index. Among the hybrids studied, UOP-53 x UOP-1185, UOP-79 x UOP-60 and UOP-80 x UOP-20 were identified as promising with desirable yield and yield attributes. They can be handled for the exploitation of heterosis and to obtain suitable segregants.

Assessment of the morphological and molecular diversity in Amaranthus spp.

Genetic diversity and relationships of 15 Amaranthus species were examined by using both morphological traits and random amplification of polymorphic DNA (RAPD) markers. Ten morphological observations were recorded out of which seven were subjected to analysis of variance. Mean squares due to genotypes were highly significant. Wide mean range performance was observed for number of effective tillers per plant (9 to 12.3), spike length (16.7 to 42.4 cm), spike mass (16.2 to 24.5 g), seed yield per plant (6.4 to 16.6 g), biological yield per plant (19.8 to 28.6 g), harvest index (32.9 to 57.1%) and seed protein content (15.75 to 16.49). RAPD analysis has been carried out using 12 arbitrary sequence decamer primers. Seventy four amplicons were obtained out of which 58 were polymorphic and the level of polymorphism was 78.3%. The average number of polymorphic bands per primer was 4.8. From the RAPD data, an unweighted pair-group method arithmetic (UPGMA) dendrogram illustrating the genetic relationship among fifteen genotypes were computed. The trends of genotypes relationship amongst the Amaranths spp. determined by RAPDs are consistent with their morphological traits.

Assessment of genetic diversity in black gram [Vigna mungo (L.) Hepper] genotypes based on ISSR

A study was carried out among 22 black gram genotypes to study the genetic diversity using 20 ISSR primers. Screening of the primers revealed that only 15 out of the 20 primers produced amplification. A total of 84 amplified bands were obtained, out of which 72 were polymorphic 85.71 percent polymorphism. The total number of amplified bands varied between 1 (UBC-813 and UBC-878) and 9 (UBC-826) with an average of 5 bands per primer. The overall size of PCR amplified products ranged between 250 bp to 2000 bp. PIC values ranged from 0.00 to 0.51 with an average of 0.285 across all genotypes. Five unique bands were detected in four genotypes, out of which the genotype U-9 gave maximum number of distinct bands. The size of these unique bands ranged from 450 bp to 2000 bp. Based on the UPGMA derived dendrogram and PCA, the 22 genotypes could be divided into four main clusters. While Cluster I included 16 genotypes, the Clusters II, III and IV included two genotypes each. Genotypes IC-16511 and UTTARA, UH-177 and IPU2K-21, STY-2834 and UH-177 were found to be genetically distant from each other with a minimum similarity value of 0.42. The results are encouraging with the suggestion that the ISSR marker could prove to be a versatile tool in further screening of the Vigna germplasm pool for study of genetic divergence and the establishment of phylogenetic relationship amongst accessions.

SSR-Marker assisted evaluation of Genetic Diversity in Mungbean ( Vigna radiata (L.) Wilcezk) genotypes

Mungbean (Vigna radiata (L.) Wilczek) also known as green gram is an important source of protein in the category of food legumes. In the present study, SSR marker is used to analyze the genetic diversity amongst 23 genotypes of mungbean. Out of a total of 10 primers used for SSR analysis revealed generation of 15 alleles. The number of alleles per locus ranged from one (CEDG006, CEDG010, CEDG050, CEDG088, CEDG092 and CEDG232) to three (CEDG 214), with an average of 1.5 allele per primer. The index for expected heterozygosity was 0.29 ranging from 0.15 to 0.49 revealed a deficit in heterozygosity. The size of amplification products varied in case of each primer and the range was found to be 100 bp to 190 bp. 13 out of 15 alleles were found polymorphic. The average PIC value of SSR marker was found to be 0.205. The value of Jaccard’s similarity coefficient had ranged from 0.28-1.00 with an average value of 0.64. The dendrogram constructed on SSR molecular marker data through UPGMA method and PCA using average linkage, had enabled grouping of the genotypes into three main clusters. Clustering pattern based on SSR marker data clearly indicated the narrow genetic base of mungbean genotypes that emphasizes the need to explore and exploit more number of germplasm from additional source to study genetic variation in mungbean for genetic improvement. The results indicated the marked usefulness of SSR in the assessment of genetic diversity in mungbean crop.

Study on genetic variability, heritability and genetic advance in Soybean[Glycine max (L.) Merrill]

Soybean, an important legume crop, serves as a good source of protein and oil with tremendous ability to fix atmospheric nitrogen for soil improvement. To study the genetic variability, genotypic, phenotypic and environmental coefficient of variation, broad sense heritability and genetic advance in soybean, a field experiment was conducted during Kharif 2013. The experiment, laid out in a randomized block design (RBD) with three replications, comprised of 24 genotypes and observations on 9 traits of soybean were recorded. In this experiment, analysis of variance indicated that significant variation were present among the different genotypes of the soybean for all the traits under study. The highest genotypic (GCV) and phonotypic coefficient of variation (PCV) were exhibited by the test weight, number of pods per plant, harvest index and plant height. The PCV was found higher than GCV which indicates the important role of environment in the expression of the characters. High heritability and high genetic advance were observed in the test weight, number of pods per plant, harvest index and plant height. The combination of the high heritability and high genetic advance provide the clear image of the trait in the selection process for crop improvement programme.

Diversity analysis among opium poppy (Papaver somniferum L.) crosses and parents using RAPD

The RAPD analysis was carried out with 28 crosses, 8 parents and 2 checks of opium poppy. Purified and isolated DNA was subjected to PCR based marker (RAPD) for assessment of genetic diversity. The quality of DNA was determined by calculating ratio between A260 and A280 observed between 1.857 to 2.167 which indicated a good quality of plant DNA. The concentration of DNA ranged between 123 μg/μl (UOP-60 x UOP99) to 750 μg/μl (UOP-79 x UOP80). In the RAPD analysis 12 primers gave good amplified products with template DNA. Polymorphism shown by 12 primers ranged between 50 per cent (OPP-02) to 100 per cent (OPA-01, OPA-08, OPB-06 and OPD-05). Average polymorphism was found to be 84.80 per cent. From RAPD profiling similarly matrix was obtained and Jaccard’s similarity coefficient lies between 0.57 (UOP-69 x UOP-80) to 0.95 (UOP-53 x UOP-79) with an average of 0.79. On this basis a dendrogram was constructed with UPGMA method. Dendrogram differentiate 28 crosses, eight parents and to checks of opium poppy into one major and four minor groups. Further genetically diverse parents and crosses can be alternatively used for accumulating favourable genes so as to finally improve the productivity.

Combining ability analysis for latex yield and its related traits in opium poppy (Papaver somniferum L.)

Combining ability studies for eight parents and their all possible crosses (excluding reciprocals) of opium poppy were grown at experimental farm of Plant Breeding and Genetics, Rajasthan College of Agriculture, Maharana Pratap University of Agriculture and Technology, Udaipur (Rajasthan). This experiment was conducted in random block design with three replications and estimate combining ability for latex yield and yield related traits. Combining ability analysis indicated that mean square due to gca and sca were significant for all the characters, expect for plant height for sca, indicating the importance of both additive as well as non-additive genetic effect for the inheritance of all the characters under pooled over environments. Parents UOP-69, UOP-80 and UOP-99 were good general combiners for most of the important characters specially latex yield per plant, seed yield per plant, effective capsules per plant, seed harvest index and morphine content in pooled over the environments. The parent UOP-53 was also good general combiner for morphine content. The parent UOP79 possessed good nicking ability for earliness and short plant stature. On pooled basis, the hybrids UOP-80 x UOP-20, UOP-53 x UOP-1185, UOP-79 x UOP-60, UOP-79 x UOP-20, UOP-79 x UOP-1185 and UOP-80 x UOP-1185 also showed high SCA effect for latex, seed and husk yield per plant, it could be used for exploitation of heterosis for latex yield potential and other related traits.

Assessment of Genetic Diversity in Mungbean Genotypes using ISSR Markers

Assessment of Genetic Diversity in Mungbean Genotypes using ISSR Markers Molecular assessment of genetic diversity was done for 23 mungbean (Vigna radiata (L.) Wilczek) genotypes using ISSR marker system. Twenty ISSR primers were used in the study out of which thirteen primers enabled DNA amplification in all genotypes. A total of 75 amplified and reproducible amplicons were obtained from 13 primers, out of which 60 were found polymorphic. The total number of amplified bands varied between 2 (UBC-813) and 11 (UBC-810) with an average of 6.5 per primer. The overall size of PCR amplified products ranged between 200 to 2500 bp. PIC values ranged from 0.07 to 0.35 with an average value of 0.208 across all genotypes. Four unique bands were detected in four genotypes with 3 (UBC-818, UBC-820 and UBC-826) out of 13 ISSR primers. The genotype IC-393407 gave maximum number of distinct bands. The similarity indices between the 23 genotypes ranged from 0.38 to 0.94. The extent of diversity among genotypes was also estimated in relation to their source and a set of genotypes with narrow genetic bases developed from various region were identified. Based on a dendrogram generated through UPGMA method and PCA, most of the genotypes could be divided into two main clusters. Cluster I included twenty genotypes, while cluster II included three genotypes. The genotype GM-9925 lay apart from all the two clusters. A minimum similarity co-efficient of 0.38 was observed between genotypes GM-9925 and EC-398885 thereby indicating maximum genetic divergence. The Mantel statistical analysis (r = 0.92) also supported cluster analysis..