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Genetic Diversity in Nepalese Wheat Cultivars Based on Agro-Morphological Traits and Coefficients of Parentage / Joshi, Bal K. in Nepal Agriculture Research Journal, Vol. 5 (2004)
[article]
Title : Genetic Diversity in Nepalese Wheat Cultivars Based on Agro-Morphological Traits and Coefficients of Parentage Material Type: printed text Authors: Joshi, Bal K., Author ; Ashok Mudwari, Author ; Bhatta, M.R., Author Publication Date: 2004 Article on page: 7-17 p Languages : English (eng) Keywords: Agromorphological traits, coefficient of parentage, genetic diversity, Nepalese wheat cultivars Abstract: Genetic diversity between parents is necessary to derive transgenic segregants from a cross.
Coefficient of parentage (COP) and agromorphological traits (AMT) can be used to estimate
diversity among cultivars. The pedigrees of 26 bread wheat cultivars were traced back to 77
ancestors and computed coefficient of parentage for all pair-wise combinations. All the cultivars
used in the pedigree analysis were evaluated for six agromorphological traits in the National
Wheat Research Programme (NWRP), Bhairahawa, Nepal in 1996. Six quantitative variables were
used to compute dissimilarity distance matrix. Cluster and principal components analyses were
performed on the matrix of COP and AMT values. COP matrix and the matrix based on
agromorphological traits were compared. Mexico, India and Nepal were countries of the origin for
26 cultivars. A total of 77 ancestors originated from 22 different countries were used to develop
these cultivars. Most of the ancestors were aestivum (80.52%) and spring growth habit (64.94%).
Maximum dissimilarity was between RR 21 and Annapurna 3 and the most closely related pair
was Rohini and BL 1022 based on the AMT. The mean of COP for all cultivars was 0.159
0.256. The highest COP was between Annapurna 3 and Annapurna 2. Other more closely related
pairs based on COP were Kalyansona and Annapurna 2, Pasang Lhamu and Annapurna 3, UP 262
and RR 21, Vaskar and Kalyansona, NL 297 and BL 1473, Pasang Lhamu and Annapurna 1.
Completely unrelated pairs were L 52 and HD 1982, L 52 and Kalyansona, LR 64 and
Kalyansona, Kalyansona and HD 1982, PI and Kalyansona, PI and L 52, RR 21 and HD 1982, RR
21 and Kalyansona, RR 21 and PI. Fifteen ancestors were present in at least about 65% of the
cultivars. 17 ancestors had been used more frequently. Five and six clusters were formed based on
AMT and COP, respectively. Correlation coefficient between COP and AMT was 0.18 (P =
0.0168). Cultivars surveyed represent a wide range of variation for different areas of origin and
adaptation. This genetic variation may be useful for further improvement of wheat and it is
necessary to conserve them.Link for e-copy: http://elibrary.narc.gov.np/?r=72
in Nepal Agriculture Research Journal > Vol. 5 (2004) . - 7-17 p[article] Genetic Diversity in Nepalese Wheat Cultivars Based on Agro-Morphological Traits and Coefficients of Parentage [printed text] / Joshi, Bal K., Author ; Ashok Mudwari, Author ; Bhatta, M.R., Author . - 2004 . - 7-17 p.
Languages : English (eng)
in Nepal Agriculture Research Journal > Vol. 5 (2004) . - 7-17 p
Keywords: Agromorphological traits, coefficient of parentage, genetic diversity, Nepalese wheat cultivars Abstract: Genetic diversity between parents is necessary to derive transgenic segregants from a cross.
Coefficient of parentage (COP) and agromorphological traits (AMT) can be used to estimate
diversity among cultivars. The pedigrees of 26 bread wheat cultivars were traced back to 77
ancestors and computed coefficient of parentage for all pair-wise combinations. All the cultivars
used in the pedigree analysis were evaluated for six agromorphological traits in the National
Wheat Research Programme (NWRP), Bhairahawa, Nepal in 1996. Six quantitative variables were
used to compute dissimilarity distance matrix. Cluster and principal components analyses were
performed on the matrix of COP and AMT values. COP matrix and the matrix based on
agromorphological traits were compared. Mexico, India and Nepal were countries of the origin for
26 cultivars. A total of 77 ancestors originated from 22 different countries were used to develop
these cultivars. Most of the ancestors were aestivum (80.52%) and spring growth habit (64.94%).
Maximum dissimilarity was between RR 21 and Annapurna 3 and the most closely related pair
was Rohini and BL 1022 based on the AMT. The mean of COP for all cultivars was 0.159
0.256. The highest COP was between Annapurna 3 and Annapurna 2. Other more closely related
pairs based on COP were Kalyansona and Annapurna 2, Pasang Lhamu and Annapurna 3, UP 262
and RR 21, Vaskar and Kalyansona, NL 297 and BL 1473, Pasang Lhamu and Annapurna 1.
Completely unrelated pairs were L 52 and HD 1982, L 52 and Kalyansona, LR 64 and
Kalyansona, Kalyansona and HD 1982, PI and Kalyansona, PI and L 52, RR 21 and HD 1982, RR
21 and Kalyansona, RR 21 and PI. Fifteen ancestors were present in at least about 65% of the
cultivars. 17 ancestors had been used more frequently. Five and six clusters were formed based on
AMT and COP, respectively. Correlation coefficient between COP and AMT was 0.18 (P =
0.0168). Cultivars surveyed represent a wide range of variation for different areas of origin and
adaptation. This genetic variation may be useful for further improvement of wheat and it is
necessary to conserve them.Link for e-copy: http://elibrary.narc.gov.np/?r=72 Genetic Base of Wheat Cultivars Recommended in Nepal / Umesh R. Rosyara in Nepal Agriculture Research Journal, Vol. 6 (2005)
[article]
Title : Genetic Base of Wheat Cultivars Recommended in Nepal Material Type: printed text Authors: Umesh R. Rosyara, Author ; Joshi, Bal K., Author Publication Date: 2005 Article on page: 1-9 p. Languages : English (eng) Keywords: Coefficient of parentage, diversity, Triticum aestivum, wheat breeding Abstract: Plant breeding success is dependent, in part, upon the genetic diversity found within genetic
resources. The genetic base of wheat (Triticum aestivum L.) cultivars recommended in Nepal is not
well characterized. Therefore this study was carried out to quantify the genetic base of Nepalese
wheat cultivars by coefficient of parentage (COP). Analysis of pedigree information was based on
International Wheat Information System of the International Center for Maize and Wheat
Improvement (CIMMYT), which consists of WCOP for calculation of COP and WPDEND for
generating Mendelgram with contribution of ancestors to the cultivar if fully expanded. One
hundred eighteen ancestors from 23 countries were identified in the pedigree of 24 recommended
Nepalese cultivars. Of these, 32 ancestors contributed at least 1% each to the genetic base of
Nepalese cultivars, with a total contribution of 79%. Ancestors originating from USA contributed
19.8% of the genes, India 11.2%, Japan 9.5%, Argentina 7.5%, Kenya 7.5% Australia 6.2%, Brazil
5.6%, Canada 5.5%, Italy 4.1% and remaining from other countries. At 30% similarity, 18 clusters
were formed with largest cluster of five members. None of Nepalese landraces were traced in the
pedigree of these cultivars. Relatively large amount of diversity in Nepalese cultivars exits based on
their genetic background although small number of cultivars is recommended for cultivation.Link for e-copy: http://elibrary.narc.gov.np/?r=55
in Nepal Agriculture Research Journal > Vol. 6 (2005) . - 1-9 p.[article] Genetic Base of Wheat Cultivars Recommended in Nepal [printed text] / Umesh R. Rosyara, Author ; Joshi, Bal K., Author . - 2005 . - 1-9 p.
Languages : English (eng)
in Nepal Agriculture Research Journal > Vol. 6 (2005) . - 1-9 p.
Keywords: Coefficient of parentage, diversity, Triticum aestivum, wheat breeding Abstract: Plant breeding success is dependent, in part, upon the genetic diversity found within genetic
resources. The genetic base of wheat (Triticum aestivum L.) cultivars recommended in Nepal is not
well characterized. Therefore this study was carried out to quantify the genetic base of Nepalese
wheat cultivars by coefficient of parentage (COP). Analysis of pedigree information was based on
International Wheat Information System of the International Center for Maize and Wheat
Improvement (CIMMYT), which consists of WCOP for calculation of COP and WPDEND for
generating Mendelgram with contribution of ancestors to the cultivar if fully expanded. One
hundred eighteen ancestors from 23 countries were identified in the pedigree of 24 recommended
Nepalese cultivars. Of these, 32 ancestors contributed at least 1% each to the genetic base of
Nepalese cultivars, with a total contribution of 79%. Ancestors originating from USA contributed
19.8% of the genes, India 11.2%, Japan 9.5%, Argentina 7.5%, Kenya 7.5% Australia 6.2%, Brazil
5.6%, Canada 5.5%, Italy 4.1% and remaining from other countries. At 30% similarity, 18 clusters
were formed with largest cluster of five members. None of Nepalese landraces were traced in the
pedigree of these cultivars. Relatively large amount of diversity in Nepalese cultivars exits based on
their genetic background although small number of cultivars is recommended for cultivation.Link for e-copy: http://elibrary.narc.gov.np/?r=55