Dr Rakesh Pathak - Academia.edu (original) (raw)
Papers by Dr Rakesh Pathak
Most soil fungi are omnipresent and produce metabolites for their survival. These metabolites are... more Most soil fungi are omnipresent and produce metabolites for their survival. These metabolites are of considerable significance to the service of humankind. Nevertheless, some of them are toxic and harmful. The significance of these secondary metabolites in pharmaceuticals, food, agriculture, and day-to-day life is well documented. Laboratory-synthesized metabolites are of limited access and have several limitations. However, fungi can play a greater role in the supply of metabolites. Fungal-derived products have been found to possess several useful pharmacological and medicinal properties. Some are antibiotic, hypocholesterolemic, anti-cancerous, and immunosuppressive, and are used in products such as pigments, sweeteners, fungal enzymes, and lectins. Presently, many fungi are a major component of a large number of industries and have enormous capacity for improving microbial products. Discovery of novel metabolites will help to secure our health against resistant microbial species ...
Soil Biology, 2017
The nitrogen fixation is a key factor in low-input agricultural systems to sustain long-term soil... more The nitrogen fixation is a key factor in low-input agricultural systems to sustain long-term soil fertility. Plant–bacteria interactions in the rhizosphere are the determinants of plant health and soil fertility. The climatic conditions of arid and semiarid regions are often characterized by hot, dry summers, subhumid monsoon, and cold dry winter. The climatic conditions in this region restrict the buildup of soil organic matter and soils are generally deficient in nitrogen. Knowledge of rhizobial diversity from arid and semiarid areas is essential to improve their nutrient-poor fertility status. Soils of these regions often suffer from moisture stress, salinity, unfavorable pH, nutrient deficiency, mineral toxicity, temperature extremes, plant diseases, trace element deficiencies, etc., which inhibit nodulation and impose limitations on the vigor of the host legume. The tolerance to high levels of salinity and the survival and persistence in harsh desert conditions make these rhizobia highly valuable inocula to improve productivity of the leguminous plants cultivated under extreme environments. This functional diversity and tolerance to extreme environments displayed by efficient rhizobial isolates alone or co-inoculation with PGPR can be effectively utilized for improving legume crop production and productivity in arid and semiarid regions.
Journal of Environmental Biology, 2017
Pearl millet is emerging as an important irrigated summer crop in India and Africa. Flowering dur... more Pearl millet is emerging as an important irrigated summer crop in India and Africa. Flowering during summer coincides with high temperature resulting in reduced grain yield. Due to limited cultivar options for summer, different types of pearl millet genotypes were evaluated to identify sources of high temperature tolerance. Fourteen pearl millet cultivars (4 each of population and hybrids; 3 each of inbred restorers and MS lines) were evaluated under two sowing dates in such a way that the flowering was not/minimally affected by high temperature stress (non-stress-NST) and the flowering largely coincided with high o temperature (≥ 42 C), impacting the seed set and grain yield (stress-ST). The data on different parameters including grain yield was recorded and different stress indices were estimated. The total number of days each genotype flowered was reduced by ~2-3 days under high temperature stress, probably an inherent avoidance mechanism. Per cent decrease in seed set and grain o yield under stress was 2.4-29.9 and 12.2-40.9, respectively. High temperature stress (≥42 C) during flowering stage resulted in reduced seed set, tip sterility and reduced panicle exertion. Increased vegetative growth (plant height) coupled with reduction in grain yield were recorded for all the genotypes under heat stress. Under temperature stress, hybrids outperformed the others in terms of seed set and grain yield. Based on heat tolerance/susceptibility indices, seed set and grain yield CZH 233, CZP 9603, CZI 2011/5 and CZMS 21A were the best performing genotypes. High temperature affects the assimilate production and r e p r o d u c t i v e g r o w t h , t h e r e b y significantly reduced the grain yield. The results demonstrated that flowering period is an important heat sensitive stage. Genetic variability exists for flowering stage high temperature tolerance in pearl millet which can be utilized in developing improved cultivars for summer cultivation.
Indian Journal of Horticulture, 2000
Growth of pruned sukers in banana cv. Harichal were checked by the treatment of 2,4-D and augerin... more Growth of pruned sukers in banana cv. Harichal were checked by the treatment of 2,4-D and augering + kerosene oil. Among all the treatments, 2% 2,4-D was found most effective for higher bunch weight with a maximum cost: benefit ratio of 1:24.80 followed by 1:24.28 with its 4% concentration. The easily available burnt crude oil with augering can also be used as an effective method with a cost: benefit ratio of 1:14.87.
Legume Research An International Journal, 2014
The qualitative and quantitative characters in mungbean vary significantly across genotypes and e... more The qualitative and quantitative characters in mungbean vary significantly across genotypes and environments. Morphological and biochemical characterization were carried out in 44 mungbean genotypes during kharif 2009, 2010 and 2011, under rainfed conditions. The tested genotypes exhibited significant to highly significant differences with respect to all the morphological and biochemical characters studied. Five genotypes were recorded with > 3% fat, 16 with > 3% fibre, four with > 5% ash, six with > 29% protein and eight with > 65% carbohydrate contents. Fat and fibre contents were recorded with significantly higher heritability (> 90%) with corresponding PCV and GCV (> 15%) coupled with > 35% genetic advance, which validates that these characters are greatly influenced not only by the additive gene effect but also by greater proportion of heritable variation. No consistency in fat and fibre contents vis-à-vis seed yield indicated that they can be increased or decreased without detrimental effect on seed yield. However, ash and protein contents had negative correlation with nine out of 10 morphological traits, indicating that the genotypes with high protein or ash contents are not essentially high seed yielding as well. Whereas, carbohydrate contents had highly significant and positive correlations with eight out of 10 morphological traits, suggesting its usefulness as an excellent selection marker for improving seed yield.
Journal of environmental biology / Academy of Environmental Biology, India, 2015
Climatic models and predictions indicate increase in aridity world over due to global warming. Ar... more Climatic models and predictions indicate increase in aridity world over due to global warming. Arid environments occupy about one third land area of the world. A. senegal is the most important dryland resource of western Rajasthan desert ecosystem. The seeds of 13 low and high seed yielding exotic and indigenous provenances were evaluated for diversity and interrelationship among growth related seedling traits targeting establishment and end use of this species. Under the present study most of the growth related seedling traits varied within and amongst provenances. Highly significant correlation of dry biomass per plant of more than 72% with root length (73.3%), collar diameter (72.2%), shoot dryweight (99.7%), root dry weight (95.7%) and seedling length (79.9%) under the present study may be used for early selection. Similarly, highly significant positive correlation of seedling length with seven out of 12 growth related seedling traits validate strong inherent association of thes...
Journal of environmental biology, 2014
Prosopis cineraria significantly contribute to sand dune stabilization, soil fertility rejuvenati... more Prosopis cineraria significantly contribute to sand dune stabilization, soil fertility rejuvenation and is an integral component of agro-forestry systems in arid regions of India. Effect of different rhizobacterial seed treatments on seed germination and seedling traits in two genotypes of P. cineraria (HPY-1) and (FG-1) were tested. Observations on seed germination (%) and seedling traits viz., root length (cm), shoot length (cm), seedling weight (g) and seedling length of different treatments were recorded. Whereas, germination index (GI), seedling vigour index (SVI) and root/shoot length ratio were derived from the observed data. The scarification treatment with sulphuric acid for 10 minutes substantially enhanced germination from < 20% to 80-82% in control treatments. Treatments with co-inoculations of Bacillus licheniformis and Sinorhizobium kostiense or S. saheli supported the maximum seed germination and seedling growth and vigour. The maximum germination per cent (92.5%),...
Journal of environmental biology, 2012
Coriander (Coriandrum sativum L.) is an annual spice herb that belongs to umbel family Apiaceae w... more Coriander (Coriandrum sativum L.) is an annual spice herb that belongs to umbel family Apiaceae with diversified uses. We investigated the extent of variability among 22 Indian varieties of coriander using phenotypic and genetic markers. Multilocus genotyping by nine RAPD primers detected an average of intraspecific variations amounting to 66.18% polymorphism in banding patterns. Analysis of molecular variance indicated that a greater proportion of total genetic variation exists within population (98%) rather than among populations (2%). Higher values of Nei's gene diversity (h) and Shannon Information Index (i) and genetic distance analysis validate wider genetic diversity among Indian coriander varieties. Besides total internal transcribed spacer (ITS) length variations and single nucleotide polymorphisms, insertions/deletions (INDELS) were detected at seven sites in ITS-1 region. Multiple sequence alignment of 12 sequenced varieties revealed cent per cent identities of 5.8S g...
Nanoscale Engineering in Agricultural Management
Advances in Plant Breeding Strategies: Legumes, 2019
Cluster bean is an important leguminous annual crop of arid and semiarid regions of northwestern ... more Cluster bean is an important leguminous annual crop of arid and semiarid regions of northwestern India, mainly in Rajasthan and parts of Gujarat, Haryana and Punjab. India contributes about 80% of the global cluster bean production. It is a source of gum (guar gum/galactomannan), a natural hydrocolloid having unique qualities and wide applicability. It is a highly self-pollinated crop with very limited outcrossing. Limited genetic diversity for the different traits coupled with yield losses caused by different biotic and abiotic stresses have constrained intensive breeding efforts of this crop. Despite these limitations, progress has been achieved by exploiting the available diversity and different breeding methods like pedigree selection in the cluster bean improvement program with good results. Hybridization has not been successful due to the small, delicate flower resulting in a low percentage of hybrid seed setting. Mutation breeding has helped to generate some genetic variabili...
Journal of Environmental Biology, 2018
Indian Journal of Agricultural Sciences, 2011
Stability parameter, correlation and path analysis were studied during rainy (kharif) seasons of ... more Stability parameter, correlation and path analysis were studied during rainy (kharif) seasons of 2005, 2006 and 2007 among 40 genotypes of clusterbean [Cyamopsis tetragonoloba (L.) Taub.] for yield-related characters. The genotype×environment interaction was highly significant for all the traits studied and a large portion of the interaction was accounted for by the linear components for all the traits. ‘CAZG 6’, ‘RGC 1029’, ‘GAUG 003’, ‘GAUG 005’, ‘RGC 1002’, ‘HGS 880’, ‘CAZG 50’, ‘RGC 1030’, ‘RGM 114’, ‘WSP 50’, ‘HGS 02-1’ and ‘CLBH 201’were stable for favourable environments while ‘VIKAS 35’, ‘RGC 1038’, ‘RGC 1076’ and ‘GAUG 004’ were better performing and stable under unfavourable environment for seed yield and yield-attributing traits. The highest correlations were found with seed yield and pods/plant (r = 0.89), seeds/pod (r = 0.53), secondary branches/plant (r = 0.49), plant height (r = 0.48) and primary branches/plant (r = 0.29). Path analysis indicated the highest direct an...
Soil Biology
The climate of arid zones is often characterized as hot and dry summers, subhumid monsoon, and co... more The climate of arid zones is often characterized as hot and dry summers, subhumid monsoon, and cold dry winters. Rhizobia have potential to restore soil fertility and sand dune stabilization in arid regions due to higher tolerance to salt stress, elevated temperature, and drought. The rhizobia have diverse and heterogeneous group divided into alpha- and beta-proteobacteria; nevertheless, they are united by their ability to form nodules on leguminous and non-leguminous plants. Due to nitrogen-fixing ability and potential to replace nitrogen fertilizers, rhizobia are among the most intensively studied groups of microorganisms; simultaneously, testing of nodulation by different bacteria led to the establishment of cross-inoculation groups. With the advent of modern biotechnological tools and techniques such as rDNA sequencing, 16S diversity, DNA–rRNA hybridizations, and rRNA catalogues, more diversity of rhizobia could be exposed. The rhizobia isolated from leguminous plants of arid region largely belong to Bradyrhizobium, Mesorhizobium, Rhizobium, and Sinorhizobium genera on the basis of morphophysiological and molecular characterization. The specific stress-tolerant traits of these bacteria can be exploited to mitigate climate resilience in the context of global warming.
Indian Journal of Agricultural Sciences, 2011
Acacia senegal is well adapted to arid environment of western Rajasthan and has a potential to re... more Acacia senegal is well adapted to arid environment of western Rajasthan and has a potential to restore soil fertility and sand dune stabilization. There is a scope of improvement by exploiting geographical genetic diversity. It is a drought- tolerant multipurpose leguminous African tree species and also an important forest resource for gum Arabic, fuel, food and fodder. Thirteen selected plants showing significantly high and low seed yields from Rajasthan and exotic locations, viz Niger, Mali, Senegal and Sudan, transplanted in 1988 at Central Arid Zone Research Institute (CAZRI), Jodhpur, were subjected to randomly amplified polymorphic DNA (RAPD) analysis. Six random primers generated a total of 86 scorable loci and exhibited 77.77 to 94.73% polymorphism. Unweighed pair group method using arithmetic averages (UPGMA) dendrogram obtained from cluster analysis using Jaccard’s similarity coefficient delineated all the 13 population samples representing seven geographical populations. ...
Journal of Mycology and Plant Pathology, 2017
A study was conducted during 2006–07 to assess the extent of genetic variability and qualitative ... more A study was conducted during 2006–07 to assess the extent of genetic variability and qualitative characters of clusterbean (Cyamopsis tetragonoloba L. Taub.). The range, genotypic and phenotypic coefficient of variation, heritability, genetic advance and correlation among seven qualitative characters were estimated in 40 genotypes of clusterbean. The genotypes showed considerable amount of variability for all the traits. Irrespective of their place of collection the genotypes were grouped into seven different clusters. Cluster analysis revealed that genotypes ‘HGS 884’, ‘HGS 26– 01’ and ‘HGS 02-20’ will be useful for genetic resources. High magnitude of heritability and genetic advance for gum, fibre and protein contents suggested that the genotypic variation in the present material for these characters is due to high additive genetic effects. Carbohydrates were positively correlated with endosperm and gum contents. Endosperm exhibited significant positive association with gum conte...
Biologia Futura
Twenty-six morphotypes of actinomycetes bacteria were isolated from the soils of arid zone of Ind... more Twenty-six morphotypes of actinomycetes bacteria were isolated from the soils of arid zone of Indian Thar desert, Rajasthan. A significant and positive correlation was found between density of actinomycetes isolates and availability of nitrogen in sandy soil of arid zone suggesting the influence of soil nitrogen on occurrence and propagation of actinomycetes in this region. Molecular identification based on 16S rRNA gene sequencing revealed that the bacterial isolates belong to four actinomycetes genera, viz. Streptomyces (22 species), Nocardiopsis (two species), Saccharomonospora (one species) and Actinoalloteichus (one species). The preliminary screening of 26 isolates against five human pathogenic bacteria, viz. Escherichia coli, Vibrio cholera, Salmonella enterica typhimurium, Staphylococcus aureus and Enterococcus faecalis, showed that only four isolates, viz. Streptomyces sp. (ITD-27), S. enissocaesilis (ITD-29), S. Malachitospinus (ITD-35) and Streptomyces sp. (ITD-47), had antibacterial activity. The secondary screening of these four isolates revealed that the isolate S. malachitospinus (ITD-35) showed the maximum growth inhibition zone and inhibited the growth of all tested gram-positive and gram-negative pathogenic bacteria. Gas chromatography-mass spectrometry analysis of S. malachitospinus (ITD-35) cultural filtrate in n-butanol solvent identified three antibacterial compounds of medicinal significance, viz. 3-octanone, neopentyl isothiocyanate and 2-methyl butyl isothiocyanate.
Journal of Applied and Natural Science
The genus Nocardiopsis is well known to produce secondary metabolites especially antibacterial bi... more The genus Nocardiopsis is well known to produce secondary metabolites especially antibacterial bioactive compound. Isolation and characterization of bioactive compounds producing novel isolates from unusual habitats are crucial. The present study was aimed to explore Didwana dry salt lake of Rajasthan state in India for the isolation and characterization of actinomycetes. The isolated actinomycetes isolates were characterized based on culture characteristics, biochemical tests and 16S rRNA gene sequencing. The 16S rRNA gene sequence analysis revealed that all the five isolates inhabiting soil of the said dry salt lake of Didwana, Rajasthan belonged to four species of Nocardiopsis viz., N. synnemataformans, N. potens, N. prasina and N. dassonvillei subsp. albirubida. The molecular identification based on 16S rRNA gene sequences was found accurate and robust. The phylogram generated through multiple sequence alignment of all the test isolates of Nocardiopsis revealed that the isolates...
Indian Phytopathology
Indian Thar desert mostly covering North–Western parts of Rajasthan is known for high temperature... more Indian Thar desert mostly covering North–Western parts of Rajasthan is known for high temperature, high wind velocity, low rainfall and minimum relative humidity. The harsh climatic conditions of the region had wide fungal diversity along with several unreported species. Present study was aimed to explore the diversity of gastroid fungi from the Indian Thar desert. During survey a gastroid fungus was found growing in the rainy season under Prosopis juliflora tree. The fungal fruiting bodies were collected and identified based on microscopic examination, scanning electron microscopy (SEM) and ITS-5.8S rRNA gene sequences as gasteroid fungus Broomeia congregata Berk., belonging to family Broomeiaceae (Basidiomycota). The ITS-5.8S rRNA gene sequences of the fungus were compared with that of available sequences using BLAST programme and submitted to NCBI, USA. The nucleotide sequence was assigned GenBank accession number MK208821 which is now available in public domain. The morphological characterization and molecular identification validated B. congregata Berk. as a new record from great Indian Thar desert.
Indian Journal of Agricultural Science, 2009
Most soil fungi are omnipresent and produce metabolites for their survival. These metabolites are... more Most soil fungi are omnipresent and produce metabolites for their survival. These metabolites are of considerable significance to the service of humankind. Nevertheless, some of them are toxic and harmful. The significance of these secondary metabolites in pharmaceuticals, food, agriculture, and day-to-day life is well documented. Laboratory-synthesized metabolites are of limited access and have several limitations. However, fungi can play a greater role in the supply of metabolites. Fungal-derived products have been found to possess several useful pharmacological and medicinal properties. Some are antibiotic, hypocholesterolemic, anti-cancerous, and immunosuppressive, and are used in products such as pigments, sweeteners, fungal enzymes, and lectins. Presently, many fungi are a major component of a large number of industries and have enormous capacity for improving microbial products. Discovery of novel metabolites will help to secure our health against resistant microbial species ...
Soil Biology, 2017
The nitrogen fixation is a key factor in low-input agricultural systems to sustain long-term soil... more The nitrogen fixation is a key factor in low-input agricultural systems to sustain long-term soil fertility. Plant–bacteria interactions in the rhizosphere are the determinants of plant health and soil fertility. The climatic conditions of arid and semiarid regions are often characterized by hot, dry summers, subhumid monsoon, and cold dry winter. The climatic conditions in this region restrict the buildup of soil organic matter and soils are generally deficient in nitrogen. Knowledge of rhizobial diversity from arid and semiarid areas is essential to improve their nutrient-poor fertility status. Soils of these regions often suffer from moisture stress, salinity, unfavorable pH, nutrient deficiency, mineral toxicity, temperature extremes, plant diseases, trace element deficiencies, etc., which inhibit nodulation and impose limitations on the vigor of the host legume. The tolerance to high levels of salinity and the survival and persistence in harsh desert conditions make these rhizobia highly valuable inocula to improve productivity of the leguminous plants cultivated under extreme environments. This functional diversity and tolerance to extreme environments displayed by efficient rhizobial isolates alone or co-inoculation with PGPR can be effectively utilized for improving legume crop production and productivity in arid and semiarid regions.
Journal of Environmental Biology, 2017
Pearl millet is emerging as an important irrigated summer crop in India and Africa. Flowering dur... more Pearl millet is emerging as an important irrigated summer crop in India and Africa. Flowering during summer coincides with high temperature resulting in reduced grain yield. Due to limited cultivar options for summer, different types of pearl millet genotypes were evaluated to identify sources of high temperature tolerance. Fourteen pearl millet cultivars (4 each of population and hybrids; 3 each of inbred restorers and MS lines) were evaluated under two sowing dates in such a way that the flowering was not/minimally affected by high temperature stress (non-stress-NST) and the flowering largely coincided with high o temperature (≥ 42 C), impacting the seed set and grain yield (stress-ST). The data on different parameters including grain yield was recorded and different stress indices were estimated. The total number of days each genotype flowered was reduced by ~2-3 days under high temperature stress, probably an inherent avoidance mechanism. Per cent decrease in seed set and grain o yield under stress was 2.4-29.9 and 12.2-40.9, respectively. High temperature stress (≥42 C) during flowering stage resulted in reduced seed set, tip sterility and reduced panicle exertion. Increased vegetative growth (plant height) coupled with reduction in grain yield were recorded for all the genotypes under heat stress. Under temperature stress, hybrids outperformed the others in terms of seed set and grain yield. Based on heat tolerance/susceptibility indices, seed set and grain yield CZH 233, CZP 9603, CZI 2011/5 and CZMS 21A were the best performing genotypes. High temperature affects the assimilate production and r e p r o d u c t i v e g r o w t h , t h e r e b y significantly reduced the grain yield. The results demonstrated that flowering period is an important heat sensitive stage. Genetic variability exists for flowering stage high temperature tolerance in pearl millet which can be utilized in developing improved cultivars for summer cultivation.
Indian Journal of Horticulture, 2000
Growth of pruned sukers in banana cv. Harichal were checked by the treatment of 2,4-D and augerin... more Growth of pruned sukers in banana cv. Harichal were checked by the treatment of 2,4-D and augering + kerosene oil. Among all the treatments, 2% 2,4-D was found most effective for higher bunch weight with a maximum cost: benefit ratio of 1:24.80 followed by 1:24.28 with its 4% concentration. The easily available burnt crude oil with augering can also be used as an effective method with a cost: benefit ratio of 1:14.87.
Legume Research An International Journal, 2014
The qualitative and quantitative characters in mungbean vary significantly across genotypes and e... more The qualitative and quantitative characters in mungbean vary significantly across genotypes and environments. Morphological and biochemical characterization were carried out in 44 mungbean genotypes during kharif 2009, 2010 and 2011, under rainfed conditions. The tested genotypes exhibited significant to highly significant differences with respect to all the morphological and biochemical characters studied. Five genotypes were recorded with > 3% fat, 16 with > 3% fibre, four with > 5% ash, six with > 29% protein and eight with > 65% carbohydrate contents. Fat and fibre contents were recorded with significantly higher heritability (> 90%) with corresponding PCV and GCV (> 15%) coupled with > 35% genetic advance, which validates that these characters are greatly influenced not only by the additive gene effect but also by greater proportion of heritable variation. No consistency in fat and fibre contents vis-à-vis seed yield indicated that they can be increased or decreased without detrimental effect on seed yield. However, ash and protein contents had negative correlation with nine out of 10 morphological traits, indicating that the genotypes with high protein or ash contents are not essentially high seed yielding as well. Whereas, carbohydrate contents had highly significant and positive correlations with eight out of 10 morphological traits, suggesting its usefulness as an excellent selection marker for improving seed yield.
Journal of environmental biology / Academy of Environmental Biology, India, 2015
Climatic models and predictions indicate increase in aridity world over due to global warming. Ar... more Climatic models and predictions indicate increase in aridity world over due to global warming. Arid environments occupy about one third land area of the world. A. senegal is the most important dryland resource of western Rajasthan desert ecosystem. The seeds of 13 low and high seed yielding exotic and indigenous provenances were evaluated for diversity and interrelationship among growth related seedling traits targeting establishment and end use of this species. Under the present study most of the growth related seedling traits varied within and amongst provenances. Highly significant correlation of dry biomass per plant of more than 72% with root length (73.3%), collar diameter (72.2%), shoot dryweight (99.7%), root dry weight (95.7%) and seedling length (79.9%) under the present study may be used for early selection. Similarly, highly significant positive correlation of seedling length with seven out of 12 growth related seedling traits validate strong inherent association of thes...
Journal of environmental biology, 2014
Prosopis cineraria significantly contribute to sand dune stabilization, soil fertility rejuvenati... more Prosopis cineraria significantly contribute to sand dune stabilization, soil fertility rejuvenation and is an integral component of agro-forestry systems in arid regions of India. Effect of different rhizobacterial seed treatments on seed germination and seedling traits in two genotypes of P. cineraria (HPY-1) and (FG-1) were tested. Observations on seed germination (%) and seedling traits viz., root length (cm), shoot length (cm), seedling weight (g) and seedling length of different treatments were recorded. Whereas, germination index (GI), seedling vigour index (SVI) and root/shoot length ratio were derived from the observed data. The scarification treatment with sulphuric acid for 10 minutes substantially enhanced germination from < 20% to 80-82% in control treatments. Treatments with co-inoculations of Bacillus licheniformis and Sinorhizobium kostiense or S. saheli supported the maximum seed germination and seedling growth and vigour. The maximum germination per cent (92.5%),...
Journal of environmental biology, 2012
Coriander (Coriandrum sativum L.) is an annual spice herb that belongs to umbel family Apiaceae w... more Coriander (Coriandrum sativum L.) is an annual spice herb that belongs to umbel family Apiaceae with diversified uses. We investigated the extent of variability among 22 Indian varieties of coriander using phenotypic and genetic markers. Multilocus genotyping by nine RAPD primers detected an average of intraspecific variations amounting to 66.18% polymorphism in banding patterns. Analysis of molecular variance indicated that a greater proportion of total genetic variation exists within population (98%) rather than among populations (2%). Higher values of Nei's gene diversity (h) and Shannon Information Index (i) and genetic distance analysis validate wider genetic diversity among Indian coriander varieties. Besides total internal transcribed spacer (ITS) length variations and single nucleotide polymorphisms, insertions/deletions (INDELS) were detected at seven sites in ITS-1 region. Multiple sequence alignment of 12 sequenced varieties revealed cent per cent identities of 5.8S g...
Nanoscale Engineering in Agricultural Management
Advances in Plant Breeding Strategies: Legumes, 2019
Cluster bean is an important leguminous annual crop of arid and semiarid regions of northwestern ... more Cluster bean is an important leguminous annual crop of arid and semiarid regions of northwestern India, mainly in Rajasthan and parts of Gujarat, Haryana and Punjab. India contributes about 80% of the global cluster bean production. It is a source of gum (guar gum/galactomannan), a natural hydrocolloid having unique qualities and wide applicability. It is a highly self-pollinated crop with very limited outcrossing. Limited genetic diversity for the different traits coupled with yield losses caused by different biotic and abiotic stresses have constrained intensive breeding efforts of this crop. Despite these limitations, progress has been achieved by exploiting the available diversity and different breeding methods like pedigree selection in the cluster bean improvement program with good results. Hybridization has not been successful due to the small, delicate flower resulting in a low percentage of hybrid seed setting. Mutation breeding has helped to generate some genetic variabili...
Journal of Environmental Biology, 2018
Indian Journal of Agricultural Sciences, 2011
Stability parameter, correlation and path analysis were studied during rainy (kharif) seasons of ... more Stability parameter, correlation and path analysis were studied during rainy (kharif) seasons of 2005, 2006 and 2007 among 40 genotypes of clusterbean [Cyamopsis tetragonoloba (L.) Taub.] for yield-related characters. The genotype×environment interaction was highly significant for all the traits studied and a large portion of the interaction was accounted for by the linear components for all the traits. ‘CAZG 6’, ‘RGC 1029’, ‘GAUG 003’, ‘GAUG 005’, ‘RGC 1002’, ‘HGS 880’, ‘CAZG 50’, ‘RGC 1030’, ‘RGM 114’, ‘WSP 50’, ‘HGS 02-1’ and ‘CLBH 201’were stable for favourable environments while ‘VIKAS 35’, ‘RGC 1038’, ‘RGC 1076’ and ‘GAUG 004’ were better performing and stable under unfavourable environment for seed yield and yield-attributing traits. The highest correlations were found with seed yield and pods/plant (r = 0.89), seeds/pod (r = 0.53), secondary branches/plant (r = 0.49), plant height (r = 0.48) and primary branches/plant (r = 0.29). Path analysis indicated the highest direct an...
Soil Biology
The climate of arid zones is often characterized as hot and dry summers, subhumid monsoon, and co... more The climate of arid zones is often characterized as hot and dry summers, subhumid monsoon, and cold dry winters. Rhizobia have potential to restore soil fertility and sand dune stabilization in arid regions due to higher tolerance to salt stress, elevated temperature, and drought. The rhizobia have diverse and heterogeneous group divided into alpha- and beta-proteobacteria; nevertheless, they are united by their ability to form nodules on leguminous and non-leguminous plants. Due to nitrogen-fixing ability and potential to replace nitrogen fertilizers, rhizobia are among the most intensively studied groups of microorganisms; simultaneously, testing of nodulation by different bacteria led to the establishment of cross-inoculation groups. With the advent of modern biotechnological tools and techniques such as rDNA sequencing, 16S diversity, DNA–rRNA hybridizations, and rRNA catalogues, more diversity of rhizobia could be exposed. The rhizobia isolated from leguminous plants of arid region largely belong to Bradyrhizobium, Mesorhizobium, Rhizobium, and Sinorhizobium genera on the basis of morphophysiological and molecular characterization. The specific stress-tolerant traits of these bacteria can be exploited to mitigate climate resilience in the context of global warming.
Indian Journal of Agricultural Sciences, 2011
Acacia senegal is well adapted to arid environment of western Rajasthan and has a potential to re... more Acacia senegal is well adapted to arid environment of western Rajasthan and has a potential to restore soil fertility and sand dune stabilization. There is a scope of improvement by exploiting geographical genetic diversity. It is a drought- tolerant multipurpose leguminous African tree species and also an important forest resource for gum Arabic, fuel, food and fodder. Thirteen selected plants showing significantly high and low seed yields from Rajasthan and exotic locations, viz Niger, Mali, Senegal and Sudan, transplanted in 1988 at Central Arid Zone Research Institute (CAZRI), Jodhpur, were subjected to randomly amplified polymorphic DNA (RAPD) analysis. Six random primers generated a total of 86 scorable loci and exhibited 77.77 to 94.73% polymorphism. Unweighed pair group method using arithmetic averages (UPGMA) dendrogram obtained from cluster analysis using Jaccard’s similarity coefficient delineated all the 13 population samples representing seven geographical populations. ...
Journal of Mycology and Plant Pathology, 2017
A study was conducted during 2006–07 to assess the extent of genetic variability and qualitative ... more A study was conducted during 2006–07 to assess the extent of genetic variability and qualitative characters of clusterbean (Cyamopsis tetragonoloba L. Taub.). The range, genotypic and phenotypic coefficient of variation, heritability, genetic advance and correlation among seven qualitative characters were estimated in 40 genotypes of clusterbean. The genotypes showed considerable amount of variability for all the traits. Irrespective of their place of collection the genotypes were grouped into seven different clusters. Cluster analysis revealed that genotypes ‘HGS 884’, ‘HGS 26– 01’ and ‘HGS 02-20’ will be useful for genetic resources. High magnitude of heritability and genetic advance for gum, fibre and protein contents suggested that the genotypic variation in the present material for these characters is due to high additive genetic effects. Carbohydrates were positively correlated with endosperm and gum contents. Endosperm exhibited significant positive association with gum conte...
Biologia Futura
Twenty-six morphotypes of actinomycetes bacteria were isolated from the soils of arid zone of Ind... more Twenty-six morphotypes of actinomycetes bacteria were isolated from the soils of arid zone of Indian Thar desert, Rajasthan. A significant and positive correlation was found between density of actinomycetes isolates and availability of nitrogen in sandy soil of arid zone suggesting the influence of soil nitrogen on occurrence and propagation of actinomycetes in this region. Molecular identification based on 16S rRNA gene sequencing revealed that the bacterial isolates belong to four actinomycetes genera, viz. Streptomyces (22 species), Nocardiopsis (two species), Saccharomonospora (one species) and Actinoalloteichus (one species). The preliminary screening of 26 isolates against five human pathogenic bacteria, viz. Escherichia coli, Vibrio cholera, Salmonella enterica typhimurium, Staphylococcus aureus and Enterococcus faecalis, showed that only four isolates, viz. Streptomyces sp. (ITD-27), S. enissocaesilis (ITD-29), S. Malachitospinus (ITD-35) and Streptomyces sp. (ITD-47), had antibacterial activity. The secondary screening of these four isolates revealed that the isolate S. malachitospinus (ITD-35) showed the maximum growth inhibition zone and inhibited the growth of all tested gram-positive and gram-negative pathogenic bacteria. Gas chromatography-mass spectrometry analysis of S. malachitospinus (ITD-35) cultural filtrate in n-butanol solvent identified three antibacterial compounds of medicinal significance, viz. 3-octanone, neopentyl isothiocyanate and 2-methyl butyl isothiocyanate.
Journal of Applied and Natural Science
The genus Nocardiopsis is well known to produce secondary metabolites especially antibacterial bi... more The genus Nocardiopsis is well known to produce secondary metabolites especially antibacterial bioactive compound. Isolation and characterization of bioactive compounds producing novel isolates from unusual habitats are crucial. The present study was aimed to explore Didwana dry salt lake of Rajasthan state in India for the isolation and characterization of actinomycetes. The isolated actinomycetes isolates were characterized based on culture characteristics, biochemical tests and 16S rRNA gene sequencing. The 16S rRNA gene sequence analysis revealed that all the five isolates inhabiting soil of the said dry salt lake of Didwana, Rajasthan belonged to four species of Nocardiopsis viz., N. synnemataformans, N. potens, N. prasina and N. dassonvillei subsp. albirubida. The molecular identification based on 16S rRNA gene sequences was found accurate and robust. The phylogram generated through multiple sequence alignment of all the test isolates of Nocardiopsis revealed that the isolates...
Indian Phytopathology
Indian Thar desert mostly covering North–Western parts of Rajasthan is known for high temperature... more Indian Thar desert mostly covering North–Western parts of Rajasthan is known for high temperature, high wind velocity, low rainfall and minimum relative humidity. The harsh climatic conditions of the region had wide fungal diversity along with several unreported species. Present study was aimed to explore the diversity of gastroid fungi from the Indian Thar desert. During survey a gastroid fungus was found growing in the rainy season under Prosopis juliflora tree. The fungal fruiting bodies were collected and identified based on microscopic examination, scanning electron microscopy (SEM) and ITS-5.8S rRNA gene sequences as gasteroid fungus Broomeia congregata Berk., belonging to family Broomeiaceae (Basidiomycota). The ITS-5.8S rRNA gene sequences of the fungus were compared with that of available sequences using BLAST programme and submitted to NCBI, USA. The nucleotide sequence was assigned GenBank accession number MK208821 which is now available in public domain. The morphological characterization and molecular identification validated B. congregata Berk. as a new record from great Indian Thar desert.
Indian Journal of Agricultural Science, 2009