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Singh S.K.,Indian Central Arid Zone Research Institute
Journal of environmental biology / Academy of Environmental Biology, India | Year: 2012

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 gene region (162 bp) that validates its conserved nature. Multiple sequence alignment of ITS-1 region may be of phylogenetic significance in distinguishing and cataloguing of coriander germplasm. The representative sequences of each subgroup and all distinct varieties of RAPD clusters have been submitted to NCBI database and assigned Gen Accession numbers HQ 377194-377205. The measures of relative genetic distances among the varieties of coriander did not completely correlate the geographical places of their development. Eventually, the knowledge of their genetic relationships and DNA bar coding will be of significance. Source

Yadav O.P.,Indian Central Arid Zone Research Institute | Rai K.N.,Indian International Crops Research Institute for the Semi Arid Tropics
Crop Science | Year: 2011

Pearl millet [Pennisetum glaucum (L.) R. Br.] is an important cereal crop of arid and drier semiarid regions of south Asia and Africa valued for both grain and stover. Drought is the most common production constraint in these regions. Drought-resilient landraces are widely grown but their cultivation results in a yield penalty under favorable conditions. Both high productivity and adaptation to drought stress are essential for cultivars targeted for arid regions. This study was conducted to assess whether crosses between Indian pearl millet landraces and African elite composites offer any advantage over landraces. Twenty-five crosses produced by hybridizing five Indian landraces with five African elite composites were evaluated for three seasons (2006-2008) at Jodhpur, India. Improvement in crosses was quantified by measuring midparent heterosis and differences between crosses and their parental populations. On an average, crosses had significantly higher biomass and stover yield than both landraces and composites but had grain yield similar to the parental populations. There was differential magnitude and direction of midparent heterosis for various traits: heterosis was positive for bio-mass (10%) and stover yield (12%) but negative for harvest index (-7%). Although there was little overall heterosis for grain yield, a few individual crosses had significant grain yield heterosis up to +33%. More than one-third of the crosses had greater grain and stover yields than their landrace parent, resulting in a mean advantage of 18% in their total crop value over land-races. These results indicate that hybridization of Indian landraces with elite composites based on African germplasm is an attractive and useful strategy to enhance biomass, stover, and grain productivity under drought-prone conditions. © Crop Science Society of America. Source

Machiwal D.,Indian Central Arid Zone Research Institute | Jha M.K.,Indian Institute of Technology Kharagpur
Hydrological Processes | Year: 2014

The aim of this study was to investigate rainfall-groundwater dynamics over space and annual time scales in a hard-rock aquifer system of India by employing time series, geographic information system and geostatistical modelling techniques. Trends in 43-year (1965-2007) annual rainfall time series of ten rainfall stations and 16-year (1991-2006) pre-monsoon and post-monsoon groundwater levels of 140 sites were identified by using Mann-Kendall, Spearman rank order correlation and Kendall rank correlation tests. Trends were quantified by Kendall slope method. Furthermore, the study involves novelty of examining homogeneity of pre-monsoon and post-monsoon groundwater levels, for the first time, by applying seven tests. Regression analysis between rainfall and post-monsoon groundwater levels was performed. The pre-monsoon and post-monsoon groundwater levels for four periods - 1991-1994, 1995-1998, 1999-2002 and 2003-2006 - were subjected to geographic information system-based geostatistical modelling. The rainfall showed considerable spatiotemporal variations, with a declining trend at the Mavli rainfall station (p-value<0.05). The Levene's tests revealed spatial homogeneity of rainfall at α=0.05. Regression analyses indicated significant relationships (r2>0.5) between groundwater level and rainfall for eight rainfall stations. Non-homogeneity and declining trends in the groundwater level, attributed to anthropogenic and hydrologic factors, were found at 5-61 more sites in pre-monsoon compared with post-monsoon season. The groundwater declining rates in phyllite-schist, gneiss, schist and granite formations were found to be 0.18, 0.26, 0.21 and 0.14myear-1 and 0.13, 0.19, 0.16 and 0.02myear-1 during the pre-monsoon and post-monsoon seasons, respectively. The geostatistical analyses for four time periods revealed linkages between the rainfall and groundwater levels. © 2013 John Wiley & Sons, Ltd. Source

Yadav O.P.,Indian Central Arid Zone Research Institute
Field Crops Research | Year: 2010

Drought is the primary constraint in pearl millet (Pennisetum glaucum) production in the drier semi-arid and arid regions of south Asia and Africa. The traditional landraces from drier regions are good sources of drought adaptation but often lack high yield under near-optimum growing environments. The objective of this paper was to assess whether crosses between landrace populations and elite germplasm can produce hybrids with better grain yield under favourable conditions than landraces, without compromising grain yield under drought. The research evaluated 20 crosses and their nine parents (consisting of landrace-based populations and elite composites) under drought and non-drought conditions. Drought response index (DRI), based on flowering and grain yield measured in drought and non-drought environments, was used to assess drought tolerance. Landrace populations yielded significantly more grain under drought stress than elite composites and crosses and had the highest mean DRI (3.99). In contrast, composites showed maximum sensitivity to drought with significantly negative DRI (-3.64). Adaptation to either drought or high productivity conditions appeared to be associated with different plant types: higher panicle number, lower grain number per panicle, and smaller seed size were associated with drought adaptation; low tillering and greater number of large-sized seeds per panicle were favoured for optimum growing conditions. Crosses yielded significantly better than composites under drought, better than landrace populations under non-drought and had a wide range in drought sensitivity. Around 40% of crosses produced on average 23% higher grain yield than the best landrace under favourable conditions, without compromising grain yield under drought. The results illustrate that hybridization of landrace populations with elite composites can produce germplasm that combines drought tolerance of traditional material with high production potential of elite genetic material. © 2010 Elsevier B.V. Source

Srivastava S.,Indian Central Arid Zone Research Institute | Srivastava A.K.,DRDO Defence Research & Development Establishment
Journal of Food Science and Technology | Year: 2013

Lycopene, the predominant carotenoid in tomatoes, is among the major carotenoids in serum and tissues of humans. Epidemiological studies have proven the bioactive role and potential disease prevention property of carotenoids and their consumption has been associated with reduced risk of degenerative diseases. Lycopene is reported to have a variety of pharmacological and nutritional effects in animals and humans, on one hand and promising health benefits as an antioxidant on the other. However, a need exists for better exploration of its biosynthesis, metabolic aspects, tissue distribution and bioavailability. To contribute to this effort, this integrated review presents data on the physico-chemical aspects, biosynthesis and metabolism, with special focus on the stability and degradation under various abiotic parameters. Heat light and oxygen are the main factors which induce degradation of lycopene via trans-cis isomerization and oxidation and reduce its health benefits. The stability of lycopene is also varied in different food matrices. Controversy also exists on some issues such as bioavailability and absorption of this compound which needs to be explored further. © 2013, Association of Food Scientists & Technologists (India). Source

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