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in Rice research in Nepal : Proceedings of 24th National Summer Crops Research Workshop, Khumaltar, Lalitpur, 30-31 June 2004 / Adhikari, N.P.
Title : Evaluation of rice genotypes for resistance to bacterial blight Material Type: printed text Authors: B. Chaudhary ; M Yadav, Author ; Yadaw, R.B., Author ; DB Gharti, Author ; Akhtar, T., Author ; Bhandari, D., Author Pagination: 344-348 p. Languages : English (eng) Keywords: Bacterial blight ; rice lines resistance locations pathotypes Abstract: A total of 244 rice lines in 2002 with a diverse genetic background and 248 in 2003 were
tested for resistance to bacterial blight (BB) over locations. Disease severity ranged from 0
to 9 in both the years. Genotypes differed in disease reaction to BB over locations. During
2002, 4 genotypes scored resistant (R), 104 moderately resistant (MR), 101 moderately
susceptible (MS), 46 susceptible (S) and 19 highly susceptible (HS) to BB at Hardinath. At
Parwanipur, 201 genotypes rated immune. 36 R, 25 MR. and 10 MS to BB. At Bhairahawa, 3
genotypes showed R, 146 MR. 75 MS. 37 Sand 13 HS to BB. During 2003, 3 genotypes
registered R. 112 lv!R. 82 MS, 42 Sand 23 HS to BB at Hardinath while 16 entries did not
germinate. At Parwanipur, 85 enrries were immune, 109 R, 53 MR and 17 MS to BB while 13
entries failed to germinate. At Bhairahawa, 3 entries recorded R, 51 MR. 62 MS, 65 Sand 97
HS to disease. However, 58 and 22 genotypes were R to MR over locations during 2002 and
2003 tests, respective~v. This showed that there was prevalence of variable pathotypes over
locations and thus, genotypes need to be tested over locations to identify donor parents and
resistant genotypes for recommendation.
Out of 216 genotypes including standard and local r;hecks received from International Rice
Research Institute. 45 entries were R, 92 MR. 49 MS. 23 S and 4 HS to BB in 2003 test at
Hardinath, and the rest 3 entries did not germinate.Link for e-copy: http://elibrary.narc.gov.np/?r=1121 Evaluation of rice genotypes for resistance to bacterial blight [printed text] / B. Chaudhary ; M Yadav, Author ; Yadaw, R.B., Author ; DB Gharti, Author ; Akhtar, T., Author ; Bhandari, D., Author . - [s.d.] . - 344-348 p.
in Rice research in Nepal : Proceedings of 24th National Summer Crops Research Workshop, Khumaltar, Lalitpur, 30-31 June 2004 / Adhikari, N.P.
Languages : English (eng)
Keywords: Bacterial blight ; rice lines resistance locations pathotypes Abstract: A total of 244 rice lines in 2002 with a diverse genetic background and 248 in 2003 were
tested for resistance to bacterial blight (BB) over locations. Disease severity ranged from 0
to 9 in both the years. Genotypes differed in disease reaction to BB over locations. During
2002, 4 genotypes scored resistant (R), 104 moderately resistant (MR), 101 moderately
susceptible (MS), 46 susceptible (S) and 19 highly susceptible (HS) to BB at Hardinath. At
Parwanipur, 201 genotypes rated immune. 36 R, 25 MR. and 10 MS to BB. At Bhairahawa, 3
genotypes showed R, 146 MR. 75 MS. 37 Sand 13 HS to BB. During 2003, 3 genotypes
registered R. 112 lv!R. 82 MS, 42 Sand 23 HS to BB at Hardinath while 16 entries did not
germinate. At Parwanipur, 85 enrries were immune, 109 R, 53 MR and 17 MS to BB while 13
entries failed to germinate. At Bhairahawa, 3 entries recorded R, 51 MR. 62 MS, 65 Sand 97
HS to disease. However, 58 and 22 genotypes were R to MR over locations during 2002 and
2003 tests, respective~v. This showed that there was prevalence of variable pathotypes over
locations and thus, genotypes need to be tested over locations to identify donor parents and
resistant genotypes for recommendation.
Out of 216 genotypes including standard and local r;hecks received from International Rice
Research Institute. 45 entries were R, 92 MR. 49 MS. 23 S and 4 HS to BB in 2003 test at
Hardinath, and the rest 3 entries did not germinate.Link for e-copy: http://elibrary.narc.gov.np/?r=1121 E-copies
http://nkcs.org.np/narc/dl/?r=1121URL
in Rice research in Nepal : Proceedings of 24th National Summer Crops Research Workshop, Khumaltar, Lalitpur, 30-31 June 2004 / Adhikari, N.P.
Title : Evaluation of rice genotypes for resistance to blast disease Material Type: printed text Authors: B. Chaudhary ; M Yadav, Author ; Yadaw, R.B., Author ; Chaudhary, D.K., Author ; PCP Chaurasiya, Author ; Chaudhary, R.N., Author ; B.N Mahato, Author ; Sah, D.N., Author Pagination: 327-335 p. Languages : English (eng) Keywords: Blast fungus ; rice genotypes sources of resistance pathogen variability Abstract: exotic were evaluated for resistance to blast over four locations during 2002 and 2003,
respectively. Disease severity varied over locations and years. Within locations, genotypes
showed variation in disease severity. During 2002, 186 entries were resistant (R), 40
moderately resistant (MR.), 14 moderately susceptible {MS), 32 susceptible (S) to disease at
Hardinath. At Lumle, 69 entries scored R, 75 MR, 66 MS and 62 S to the disease. At Rampur,
174 entries rated R, 19 MR and 3 MS to the disease while 78 failed to germinate. At
Tarahara, 236 entries showed R, 6 MR and 30 entries did nopt germinate. During 2003, 148
entries showed R, 16 MR, 4 MS and 20 S to the disease at Hardinath. At Tarahara, all the
tested entries were resistant to disease, indicating escape from disease during the growing
season. At Khumaltar, 169 entries scored R, 59 MR, 29 MS and 8 S to disease. At Nawalpur,
217 entries rated R, 21 MR, 9 MS and 11 S to the disease. However, 39 and 123 lines were
resistant to the pathogen over locations during 2002 and 2003 tests, respectively. This
indicated that the genotypes varied for disease reaction over locations suggesting the
prevalence of variable virulence in the pathogen population. In neck blast screening, 11
genotypes out of 274 entries showed R to MR to the disease over Hardinath and Rampur
during 2002 test. In 2003, 132 genotypes were R to MR to the disease at Hardinath. Blast
nursery also included 166 entries received from International Rice Research Institute in
2002. Of them, 60 entries were found resistant to the disease over Hardinath and Rampur.Link for e-copy: http://elibrary.narc.gov.np/?r=1119 Evaluation of rice genotypes for resistance to blast disease [printed text] / B. Chaudhary ; M Yadav, Author ; Yadaw, R.B., Author ; Chaudhary, D.K., Author ; PCP Chaurasiya, Author ; Chaudhary, R.N., Author ; B.N Mahato, Author ; Sah, D.N., Author . - [s.d.] . - 327-335 p.
in Rice research in Nepal : Proceedings of 24th National Summer Crops Research Workshop, Khumaltar, Lalitpur, 30-31 June 2004 / Adhikari, N.P.
Languages : English (eng)
Keywords: Blast fungus ; rice genotypes sources of resistance pathogen variability Abstract: exotic were evaluated for resistance to blast over four locations during 2002 and 2003,
respectively. Disease severity varied over locations and years. Within locations, genotypes
showed variation in disease severity. During 2002, 186 entries were resistant (R), 40
moderately resistant (MR.), 14 moderately susceptible {MS), 32 susceptible (S) to disease at
Hardinath. At Lumle, 69 entries scored R, 75 MR, 66 MS and 62 S to the disease. At Rampur,
174 entries rated R, 19 MR and 3 MS to the disease while 78 failed to germinate. At
Tarahara, 236 entries showed R, 6 MR and 30 entries did nopt germinate. During 2003, 148
entries showed R, 16 MR, 4 MS and 20 S to the disease at Hardinath. At Tarahara, all the
tested entries were resistant to disease, indicating escape from disease during the growing
season. At Khumaltar, 169 entries scored R, 59 MR, 29 MS and 8 S to disease. At Nawalpur,
217 entries rated R, 21 MR, 9 MS and 11 S to the disease. However, 39 and 123 lines were
resistant to the pathogen over locations during 2002 and 2003 tests, respectively. This
indicated that the genotypes varied for disease reaction over locations suggesting the
prevalence of variable virulence in the pathogen population. In neck blast screening, 11
genotypes out of 274 entries showed R to MR to the disease over Hardinath and Rampur
during 2002 test. In 2003, 132 genotypes were R to MR to the disease at Hardinath. Blast
nursery also included 166 entries received from International Rice Research Institute in
2002. Of them, 60 entries were found resistant to the disease over Hardinath and Rampur.Link for e-copy: http://elibrary.narc.gov.np/?r=1119 E-copies
http://nkcs.org.np/narc/dl/?r=1119URLEvaluation of rice genotypes for resistance to sheath blight under field contions / Bedanand Chaudhary
in Proceedings of the 27th National Summer Crops Workshop, held at Rampur, Chitawan, 18-20 April 2013, Vol. I / Giri, Y.P.
Title : Evaluation of rice genotypes for resistance to sheath blight under field contions Material Type: printed text Authors: Bedanand Chaudhary ; Nabin Kumar Dangal, Author ; Parbati Joshi, Author ; Sudeep Kumar Upadhyay, Author Pagination: 303-312 p. Languages : English (eng) Keywords: Genotypes ; resistance field conditions sheath blight Abstract: Sheath blight of rice, caused by Rhizoctonia sol ani, is one of the most important rice diseases
worldwide; however, no rice cultivar has been found to be completely resistant to this fungus .
Resistance of rice to sheath blight is quantitative, and involves two mechanisms:
physiological resistance and disease escape. Disease escape is mainly governed by plant
structure or plant morphology and physiologically resistance genotypes may exhibit disease in
the field conditions. Therefore, field screening experiments were conducted to address
morphological resistance (disease escape) in rice to sheath blight during the 2011 and 2012
wet season at Regional Agricultural Research Station, Tarahara. A total of28 in 2011 and 174
rice genotypes in 2012 were tested for morphological resistance. The susceptible hill (Swama)
of 56 day old plants was inoculated with infected pieces of rice stem. Number of infected
tillers of test entries was recorded on 14 days after inoculation and continued for three
scorings in both years at 7 day-intervals. During 20 11 disease incidence and area under
disease progress curve (AUDPC) varied significantly among the tested rice genotypes. The
varieties Tetep and lAC 165 had the lowest and highest terminal disease incidence and
AUDPC, respectively. Sabitri, MTU 1010 and IR 26 also recorded lower AUDPC values.
During 2012, rice genotypes varied for disease incidence from 0.0 to 50%. Disease incidence
progressed fast in some entries especially in quality rice. In the first scoring, 24 entries were
disease free (DF) and 32 were moderately resistant (MR). Out of 174 entries, 109, 8 and l
lines were moderately susceptible (MS), Susceptible (S) and highly susceptible (HS),
respectively. In the second scoring, 48, 26, 86 and 14 lines were DF, MR, MS and S,
respectively, to the disease. In the final scoring, IR 79913 -B-1 76-B-4, NR 1887-8-1-1-2,
IR79907-B-425-B-3 , IR 83381-B-B-7-1 and IR 87751 -20-4-4-2 were disease free. Out of
174, 29 genotypes were MR; similarly, 128, 11 and I were MS, S and HS to the disease,
respectively. Based on AUDPC values, 5 genotypes were grouped as DF, 67 as MR, 92 as MS
and 10 as S, respectively. More number of entries scored disease free in the second scoring
than that in the ftrst one. This was because separate hills were considered for scoring in the
different dates. Thus, the result showed that the disease incidence in rice genotypes differed
depending on microclimate conditions of the plantsLink for e-copy: http://elibrary.narc.gov.np/?r=916 Evaluation of rice genotypes for resistance to sheath blight under field contions [printed text] / Bedanand Chaudhary ; Nabin Kumar Dangal, Author ; Parbati Joshi, Author ; Sudeep Kumar Upadhyay, Author . - [s.d.] . - 303-312 p.
in Proceedings of the 27th National Summer Crops Workshop, held at Rampur, Chitawan, 18-20 April 2013, Vol. I / Giri, Y.P.
Languages : English (eng)
Keywords: Genotypes ; resistance field conditions sheath blight Abstract: Sheath blight of rice, caused by Rhizoctonia sol ani, is one of the most important rice diseases
worldwide; however, no rice cultivar has been found to be completely resistant to this fungus .
Resistance of rice to sheath blight is quantitative, and involves two mechanisms:
physiological resistance and disease escape. Disease escape is mainly governed by plant
structure or plant morphology and physiologically resistance genotypes may exhibit disease in
the field conditions. Therefore, field screening experiments were conducted to address
morphological resistance (disease escape) in rice to sheath blight during the 2011 and 2012
wet season at Regional Agricultural Research Station, Tarahara. A total of28 in 2011 and 174
rice genotypes in 2012 were tested for morphological resistance. The susceptible hill (Swama)
of 56 day old plants was inoculated with infected pieces of rice stem. Number of infected
tillers of test entries was recorded on 14 days after inoculation and continued for three
scorings in both years at 7 day-intervals. During 20 11 disease incidence and area under
disease progress curve (AUDPC) varied significantly among the tested rice genotypes. The
varieties Tetep and lAC 165 had the lowest and highest terminal disease incidence and
AUDPC, respectively. Sabitri, MTU 1010 and IR 26 also recorded lower AUDPC values.
During 2012, rice genotypes varied for disease incidence from 0.0 to 50%. Disease incidence
progressed fast in some entries especially in quality rice. In the first scoring, 24 entries were
disease free (DF) and 32 were moderately resistant (MR). Out of 174 entries, 109, 8 and l
lines were moderately susceptible (MS), Susceptible (S) and highly susceptible (HS),
respectively. In the second scoring, 48, 26, 86 and 14 lines were DF, MR, MS and S,
respectively, to the disease. In the final scoring, IR 79913 -B-1 76-B-4, NR 1887-8-1-1-2,
IR79907-B-425-B-3 , IR 83381-B-B-7-1 and IR 87751 -20-4-4-2 were disease free. Out of
174, 29 genotypes were MR; similarly, 128, 11 and I were MS, S and HS to the disease,
respectively. Based on AUDPC values, 5 genotypes were grouped as DF, 67 as MR, 92 as MS
and 10 as S, respectively. More number of entries scored disease free in the second scoring
than that in the ftrst one. This was because separate hills were considered for scoring in the
different dates. Thus, the result showed that the disease incidence in rice genotypes differed
depending on microclimate conditions of the plantsLink for e-copy: http://elibrary.narc.gov.np/?r=916 E-copies
http://nkcs.org.np/narc/dl/?r=916URL
in Summer crops research in Nepal: Proceedings of the 25th Summer Crops Workshop held at Kathmandu 21-23 June 2007 / Adhikari, N.P.
Title : Identification of level of field resistance to major diseases in Available genotypes of soybean at Nglrp, Rampur during 2005-2007 Material Type: printed text Authors: DB Gharti, Editor ; Darai, R., Author ; B.S Bastola, Author Publication Date: 2010 Pagination: 402-409 p. Keywords: Soybean ; yellow mosaic virus disease management field resistance Abstract: This study was undertaken with a view to find out the level of field resistance to major diseases in available genotypes of soybean at
National Grain Legume Research Program (NGLRP) Rampur during 062/063 and 063/064 B.S. and help recommend outstanding
genotypes for general cultivation. A total of 58 genotypes in Observation Nursery (OBN), 20 genotypes in Co-ordinated Varietal Trial
(CVT) and 7 cultivars in Pre-release Verification Trial (PRVT) were evaluated using nine point (1-9) rating scales. Mungbean yellow
mosaic virus, bacterial pustules (Xanthomonas axonopodis pv.glycines), rhizoctonia aerial blight (Rhizoctonia sofam} and pod blight
(Colletotrichwn trtmcatum) were the major diseases observed under Rampur condition (inner terai). Twenty nine genotypes in OBN, 11
genotypes in CVT and six genotypes in PRVT were found to possess field resistance to multiple diseases. Genotypes like AGS 87-4, PI
94159, PI 368055, G 1873, CINA-2, G-8514, PI 200451, IPBSY-179, G-1871, G-8386, LS77-16-16, SB 0095, SB 0065, CM 9133, and
PK 327 could be promoted to advanced trials and some of them could also be used as resistant donor in crossing program. Cultivars like
PK 327, AGS 87-4 and PK 7394 have been performing very well all through and hence they could be released for general cultivation.Link for e-copy: http://elibrary.narc.gov.np/?r=1044 Identification of level of field resistance to major diseases in Available genotypes of soybean at Nglrp, Rampur during 2005-2007 [printed text] / DB Gharti, Editor ; Darai, R., Author ; B.S Bastola, Author . - 2010 . - 402-409 p.
in Summer crops research in Nepal: Proceedings of the 25th Summer Crops Workshop held at Kathmandu 21-23 June 2007 / Adhikari, N.P.
Keywords: Soybean ; yellow mosaic virus disease management field resistance Abstract: This study was undertaken with a view to find out the level of field resistance to major diseases in available genotypes of soybean at
National Grain Legume Research Program (NGLRP) Rampur during 062/063 and 063/064 B.S. and help recommend outstanding
genotypes for general cultivation. A total of 58 genotypes in Observation Nursery (OBN), 20 genotypes in Co-ordinated Varietal Trial
(CVT) and 7 cultivars in Pre-release Verification Trial (PRVT) were evaluated using nine point (1-9) rating scales. Mungbean yellow
mosaic virus, bacterial pustules (Xanthomonas axonopodis pv.glycines), rhizoctonia aerial blight (Rhizoctonia sofam} and pod blight
(Colletotrichwn trtmcatum) were the major diseases observed under Rampur condition (inner terai). Twenty nine genotypes in OBN, 11
genotypes in CVT and six genotypes in PRVT were found to possess field resistance to multiple diseases. Genotypes like AGS 87-4, PI
94159, PI 368055, G 1873, CINA-2, G-8514, PI 200451, IPBSY-179, G-1871, G-8386, LS77-16-16, SB 0095, SB 0065, CM 9133, and
PK 327 could be promoted to advanced trials and some of them could also be used as resistant donor in crossing program. Cultivars like
PK 327, AGS 87-4 and PK 7394 have been performing very well all through and hence they could be released for general cultivation.Link for e-copy: http://elibrary.narc.gov.np/?r=1044 E-copies
http://nkcs.org.np/narc/dl/?r=1044URL
in Summer crops research in Nepal: Proceedings of the 25th Summer Crops Workshop held at Kathmandu 21-23 June 2007 / Adhikari, N.P.
Title : Molecular Tagging, Allele mining and marker aided breeding for blast resistance in rice Material Type: printed text Authors: Joshi, Bal K., Editor ; Bimb, Hari P., Author ; Gopal Parajuli, Author ; Bedanand Chaudhary, Author Publication Date: 2010 Pagination: 189-202 p. Keywords: Blast resistance ; DNA marker Gene tagging rice Abstract: Breeding work utilizing both genotypic and phenotypic· markers is the most effective way of achieving target. Molecular markers eg
restriction fragment length polymorphism (RFLP), single nucleotide polymorphism (SNP) and simi'~~ sequence repeat (SSR) tightly
linked to target gene have been identified in different chromosomes to impose the genetic selection ie marker assisted selection
(MAS). This paper summarize the progress and achievement made in breeding for blast resistance based on DNA markers which
help in planning blast resistance gene tagging in Nepalese rice genotypes and developing blast resistant inbred line or near isogenic
line (NIL). Blast fungus (Pyricularia oryzae Cav.) can infect plants at any growth stage from seedling to maturity and at any part eg
leaf, node, internode, neck and seed. Qualitative resistance gene may occasionally be broken down due to numerous races of blast
fungus both physiological and geographical races available in Nepal. Quantitative gene resistance and gene pyramiding are the best
alternative for creating durable resistance system. At least 40 genes conferring resistance to blast isolates with multiple alleles have
been described. Both dominant and recessive resistance alleles have been found in many rice landraces. Morphological and isozymic
markers are limited in number. Therefore, highly polymorphic and easily detectable SSR markers are being used in breeding for
blast resistance. Bulked segregant analysis (BSA) is the simple method for tagging resistance ge~e by SSR markers. Quantitative
trait loci (QTLs) have also been mapped and· most of them are linked to qualitative genes. SSR markers linked to the gene are being
used to select plants possessing the desired trait and markers throughout the genome are being used to select plants that are
genetically similar to recurrent parent. Using SSR markers it may be possible to select blast resistance genotypes at any stage of crop
development from any small part of crop, to conduct many round of selection, to select without inoculums, without scoring, and
without testing in hot spot or artificial inoculation. Molecular based blast resistance breeding work is initiated focusing on resistance
gene tagging in Nepalese rice Iandraces and transferring resistance genes in cvs Jumli Marshi, K.humal-4 and Mansuli.Link for e-copy: http://elibrary.narc.gov.np/?r=1016 Molecular Tagging, Allele mining and marker aided breeding for blast resistance in rice [printed text] / Joshi, Bal K., Editor ; Bimb, Hari P., Author ; Gopal Parajuli, Author ; Bedanand Chaudhary, Author . - 2010 . - 189-202 p.
in Summer crops research in Nepal: Proceedings of the 25th Summer Crops Workshop held at Kathmandu 21-23 June 2007 / Adhikari, N.P.
Keywords: Blast resistance ; DNA marker Gene tagging rice Abstract: Breeding work utilizing both genotypic and phenotypic· markers is the most effective way of achieving target. Molecular markers eg
restriction fragment length polymorphism (RFLP), single nucleotide polymorphism (SNP) and simi'~~ sequence repeat (SSR) tightly
linked to target gene have been identified in different chromosomes to impose the genetic selection ie marker assisted selection
(MAS). This paper summarize the progress and achievement made in breeding for blast resistance based on DNA markers which
help in planning blast resistance gene tagging in Nepalese rice genotypes and developing blast resistant inbred line or near isogenic
line (NIL). Blast fungus (Pyricularia oryzae Cav.) can infect plants at any growth stage from seedling to maturity and at any part eg
leaf, node, internode, neck and seed. Qualitative resistance gene may occasionally be broken down due to numerous races of blast
fungus both physiological and geographical races available in Nepal. Quantitative gene resistance and gene pyramiding are the best
alternative for creating durable resistance system. At least 40 genes conferring resistance to blast isolates with multiple alleles have
been described. Both dominant and recessive resistance alleles have been found in many rice landraces. Morphological and isozymic
markers are limited in number. Therefore, highly polymorphic and easily detectable SSR markers are being used in breeding for
blast resistance. Bulked segregant analysis (BSA) is the simple method for tagging resistance ge~e by SSR markers. Quantitative
trait loci (QTLs) have also been mapped and· most of them are linked to qualitative genes. SSR markers linked to the gene are being
used to select plants possessing the desired trait and markers throughout the genome are being used to select plants that are
genetically similar to recurrent parent. Using SSR markers it may be possible to select blast resistance genotypes at any stage of crop
development from any small part of crop, to conduct many round of selection, to select without inoculums, without scoring, and
without testing in hot spot or artificial inoculation. Molecular based blast resistance breeding work is initiated focusing on resistance
gene tagging in Nepalese rice Iandraces and transferring resistance genes in cvs Jumli Marshi, K.humal-4 and Mansuli.Link for e-copy: http://elibrary.narc.gov.np/?r=1016 E-copies
http://nkcs.org.np/narc/dl/?r=1016URL
