Sugarcane (Saccharum species hybrids) is a long-duration, high-water-requiring cash crop cultivat... more Sugarcane (Saccharum species hybrids) is a long-duration, high-water-requiring cash crop cultivated under different agroecological conditions. Besides experiencing vagaries of weather all the year round, the climate change, the order of the day, further aggravates effects of these abiotic stresses affecting sugarcane growth, development, sugar synthesis, its accumulation and recovery, ratooning ability and availability of the seed cane for succeeding planting. The relatively more resilience of sugarcane to abiotic stresses appears to be due to some natural endowments like a good deal of compensatory ability, C4 photosynthesis, higher temperature optima for most of the physiological activities (but for sugar accumulation), higher water-use efficiency, use of genetic complements from Saccharum spontaneum imparting tolerance to various abiotic stresses (in breeding varieties) and carbon-managing ability. Besides, some of the physiological interventions like inducing drought hardiness, ...
At early requirements analysis, resolving conflicts and evaluating design alternatives saves time... more At early requirements analysis, resolving conflicts and evaluating design alternatives saves time and effort in the forthcoming phases. Goal oriented approaches are preferred over other requirements engineering approaches for their capability to reason about the requirements and evaluate different solutions. We have enhanced and customized the goal driven reasoning approach for engineering Web applications. Our work is based upon a standard, User Requirements Notation (URN) that has been enhanced by us to suit the Web applications domain and termed WebURN. For different kinds of Web applications and level of domain knowledge, a suitable reasoning approach i.e. Qualitative or Quantitative can be chosen.We have focused on qualitative reasoning methodology in this paper, wherein subjective satisfaction values and contribution values are applied for evaluating the WebGRL graphs. Comparison with other approaches yields that this qualitative approach is more precise, resolves conflicts au...
Efficient management of plant diseases is mainly dependent on accurate and timely detection of pa... more Efficient management of plant diseases is mainly dependent on accurate and timely detection of pathogen, severity of infection, availability of disease resistant genotypes and cost effective disease control measures. Sugarcane suffers from various fungal, viral, bacterial and phytoplasmal diseases in its crop cycle. Disease indexing in sugarcane was so far based on visual detection of symptoms and it was extremely difficult to detect the pathogen in asymptomatic plants. Recent advances in molecular biology techniques have facilitated the development of specific and sensitive, diagnostic tools for detection of pathogens of various diseases of sugarcane. PCR based detection methods are now available for red rot and smut diseases, sugarcane mosaic, yellow leaf syndrome and white leaf/grassy shoot diseases, ratoon stunting disease, leaf scald, and gumming disease to name a few. There is further need to develop highly sensitive, specific and cost effective detection tools for key pathogens, which can be used for large scale sugarcane seed certification, germplasm quarantine programmes and diagnostic laboratories in order to detect these pathogens in seed cane.
Fourteen Interspecific Hybrids of Sugarcane (ISH lines) along with two commercial genotypes were ... more Fourteen Interspecific Hybrids of Sugarcane (ISH lines) along with two commercial genotypes were evaluated for yield and quality attributes to find out the genetic divergence among the genotypes and the factors governing it, and to isolate genotype of divergent and distinct ...
Genetically stable artificial autotetraploids with over 90% seed set were obtained by colchicine ... more Genetically stable artificial autotetraploids with over 90% seed set were obtained by colchicine treatment of the solanaceous species Hyoscyamus niger L. (4x = 68). The tetraploids were vigorous and had earlier been shown to yield considerably more tropane alkaloid per individual than the source diploids. The tetraploids had high bivalent frequencies at meiosis, and high fertility as a result of the formation of genetically balanced gametes. There was a systematic and significant decrease in quadrivalent frequency and an increase in bivalent frequency in three subsequent generations tested (C0, C1, C2). Possible causes of high bivalent frequency are discussed. Seed fertility can probably be increased in advanced generations by further selection for fertility and maximization of heterozygosity.Key words: Hyoscyamus niger, autotetraploid, meiosis, bivalents, fertility, selection.
Increasing sugar content in stalks is a key objective in sugarcane breeding because the major cos... more Increasing sugar content in stalks is a key objective in sugarcane breeding because the major costs in sugar production – harvesting, cane transport and milling – are nearly proportional to the weight of cane processed. However, genetic gains in sugar content using traditional breeding have been frustratingly slow. This booklet reviews the most published DNA marker studies in sugarcane, many of which have focused on sugar content. Three short chapters address sugarcane cytology, breeding and sugar metabolism. The chapter on sugarcane breeding is very ‘India-centric’, and the one on sugar metabolism does not report many recent studies. The main chapter deals with DNA markers and genomic studies in sugarcane, and discusses results from the most published papers on these topics. A deficiency is an absence of commentary about statistical issues – critical in interpreting quantitative trait loci (QTL) studies. A recurring theme is the challenges of working with this complex polyploid plant. The final chapter comments on potential future directions. This booklet does provide a useful collation of many published studies on DNA markers in sugarcane. However, I felt that it lacked a logical ‘flow’ in many parts, lacked supporting references in making many points, and could have benefited from much more editing. It also provided little discussion or insight about how markers may be applied in practice to improve genetic gains in sugarcane. While this may be partly excusable because of a lack of reports to date about markers being applied for this purpose, those attracted by the title could have dashed expectations.
Page 1. www.IndianJournals.com Members Copy, Not for Commercial Sale Downloaded From IP - 66.249.... more Page 1. www.IndianJournals.com Members Copy, Not for Commercial Sale Downloaded From IP - 66.249.67.34 on dated 18-Aug-2010 Indian J. Genet., 65(4): 327-328 (2005) Short communication Analysis of genetic fidelity ...
Sugarcane (Saccharum species hybrids) is a long-duration, high-water-requiring cash crop cultivat... more Sugarcane (Saccharum species hybrids) is a long-duration, high-water-requiring cash crop cultivated under different agroecological conditions. Besides experiencing vagaries of weather all the year round, the climate change, the order of the day, further aggravates effects of these abiotic stresses affecting sugarcane growth, development, sugar synthesis, its accumulation and recovery, ratooning ability and availability of the seed cane for succeeding planting. The relatively more resilience of sugarcane to abiotic stresses appears to be due to some natural endowments like a good deal of compensatory ability, C4 photosynthesis, higher temperature optima for most of the physiological activities (but for sugar accumulation), higher water-use efficiency, use of genetic complements from Saccharum spontaneum imparting tolerance to various abiotic stresses (in breeding varieties) and carbon-managing ability. Besides, some of the physiological interventions like inducing drought hardiness, ...
At early requirements analysis, resolving conflicts and evaluating design alternatives saves time... more At early requirements analysis, resolving conflicts and evaluating design alternatives saves time and effort in the forthcoming phases. Goal oriented approaches are preferred over other requirements engineering approaches for their capability to reason about the requirements and evaluate different solutions. We have enhanced and customized the goal driven reasoning approach for engineering Web applications. Our work is based upon a standard, User Requirements Notation (URN) that has been enhanced by us to suit the Web applications domain and termed WebURN. For different kinds of Web applications and level of domain knowledge, a suitable reasoning approach i.e. Qualitative or Quantitative can be chosen.We have focused on qualitative reasoning methodology in this paper, wherein subjective satisfaction values and contribution values are applied for evaluating the WebGRL graphs. Comparison with other approaches yields that this qualitative approach is more precise, resolves conflicts au...
Efficient management of plant diseases is mainly dependent on accurate and timely detection of pa... more Efficient management of plant diseases is mainly dependent on accurate and timely detection of pathogen, severity of infection, availability of disease resistant genotypes and cost effective disease control measures. Sugarcane suffers from various fungal, viral, bacterial and phytoplasmal diseases in its crop cycle. Disease indexing in sugarcane was so far based on visual detection of symptoms and it was extremely difficult to detect the pathogen in asymptomatic plants. Recent advances in molecular biology techniques have facilitated the development of specific and sensitive, diagnostic tools for detection of pathogens of various diseases of sugarcane. PCR based detection methods are now available for red rot and smut diseases, sugarcane mosaic, yellow leaf syndrome and white leaf/grassy shoot diseases, ratoon stunting disease, leaf scald, and gumming disease to name a few. There is further need to develop highly sensitive, specific and cost effective detection tools for key pathogens, which can be used for large scale sugarcane seed certification, germplasm quarantine programmes and diagnostic laboratories in order to detect these pathogens in seed cane.
Fourteen Interspecific Hybrids of Sugarcane (ISH lines) along with two commercial genotypes were ... more Fourteen Interspecific Hybrids of Sugarcane (ISH lines) along with two commercial genotypes were evaluated for yield and quality attributes to find out the genetic divergence among the genotypes and the factors governing it, and to isolate genotype of divergent and distinct ...
Genetically stable artificial autotetraploids with over 90% seed set were obtained by colchicine ... more Genetically stable artificial autotetraploids with over 90% seed set were obtained by colchicine treatment of the solanaceous species Hyoscyamus niger L. (4x = 68). The tetraploids were vigorous and had earlier been shown to yield considerably more tropane alkaloid per individual than the source diploids. The tetraploids had high bivalent frequencies at meiosis, and high fertility as a result of the formation of genetically balanced gametes. There was a systematic and significant decrease in quadrivalent frequency and an increase in bivalent frequency in three subsequent generations tested (C0, C1, C2). Possible causes of high bivalent frequency are discussed. Seed fertility can probably be increased in advanced generations by further selection for fertility and maximization of heterozygosity.Key words: Hyoscyamus niger, autotetraploid, meiosis, bivalents, fertility, selection.
Increasing sugar content in stalks is a key objective in sugarcane breeding because the major cos... more Increasing sugar content in stalks is a key objective in sugarcane breeding because the major costs in sugar production – harvesting, cane transport and milling – are nearly proportional to the weight of cane processed. However, genetic gains in sugar content using traditional breeding have been frustratingly slow. This booklet reviews the most published DNA marker studies in sugarcane, many of which have focused on sugar content. Three short chapters address sugarcane cytology, breeding and sugar metabolism. The chapter on sugarcane breeding is very ‘India-centric’, and the one on sugar metabolism does not report many recent studies. The main chapter deals with DNA markers and genomic studies in sugarcane, and discusses results from the most published papers on these topics. A deficiency is an absence of commentary about statistical issues – critical in interpreting quantitative trait loci (QTL) studies. A recurring theme is the challenges of working with this complex polyploid plant. The final chapter comments on potential future directions. This booklet does provide a useful collation of many published studies on DNA markers in sugarcane. However, I felt that it lacked a logical ‘flow’ in many parts, lacked supporting references in making many points, and could have benefited from much more editing. It also provided little discussion or insight about how markers may be applied in practice to improve genetic gains in sugarcane. While this may be partly excusable because of a lack of reports to date about markers being applied for this purpose, those attracted by the title could have dashed expectations.
Page 1. www.IndianJournals.com Members Copy, Not for Commercial Sale Downloaded From IP - 66.249.... more Page 1. www.IndianJournals.com Members Copy, Not for Commercial Sale Downloaded From IP - 66.249.67.34 on dated 18-Aug-2010 Indian J. Genet., 65(4): 327-328 (2005) Short communication Analysis of genetic fidelity ...
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