We selected 28 populations of Leucaena leucocephala from different geographical locations in the states of Andhra Pradesh, Tamil Nadu and Orissa of India on the basis of height and girth at breast height （GBH）. We e...We selected 28 populations of Leucaena leucocephala from different geographical locations in the states of Andhra Pradesh, Tamil Nadu and Orissa of India on the basis of height and girth at breast height （GBH）. We evaluated fiber length, optical density, wall thickness, vessel element length, vessel element diameter, specific gravity and lignin of these populations of L. leucocephala in different sites. Populations had significant variations for all growth, wood and paper parameters. Girth at breast height （GBH） and specific gravity were the most important pa- rameters for heritability and genetic gain, respectively. The minimum heritability was reported for vessel element length and genetic gain for fiber length. The populations were grouped into six clusters, cluster II had maximum number of populations （14） and clusters IV and VI had one population each. GBH contributed maximum of 34.39 % towards total divergence followed by specific gravity （14.02%）. An economic technique to produce quality seed by establishing seed orchards with genetically divergent parents was suggested. The hybridization among the populations selected from diverse clusters could produce greater heterosis needed for higher growth and suitable wood and paper manu- facturing parameters.展开更多
In this paper, we study the two-parameter maximum likelihood estimation （MLE）problem for the GE distribution with consideration of interval data. In the presence of interval data, the analytical forms for the restri...In this paper, we study the two-parameter maximum likelihood estimation （MLE）problem for the GE distribution with consideration of interval data. In the presence of interval data, the analytical forms for the restricted MLE of the parameters of GE distribution do not exist. Since interval data is kind of incomplete data, the EM algorithm can be applied to compute the MLEs of the parameters. However the EM algorithm could be less effective.To improve effectiveness, an equivalent lifetime method is employed. The two methods are discussed via simulation studies.展开更多
基金the group working under CSIR-NIMTLINew Delhi for financial and other necessary supports to the project entitled ‘Biotechnological approaches forimprovement of plant species with especial reference to pulp andpaper’
文摘We selected 28 populations of Leucaena leucocephala from different geographical locations in the states of Andhra Pradesh, Tamil Nadu and Orissa of India on the basis of height and girth at breast height （GBH）. We evaluated fiber length, optical density, wall thickness, vessel element length, vessel element diameter, specific gravity and lignin of these populations of L. leucocephala in different sites. Populations had significant variations for all growth, wood and paper parameters. Girth at breast height （GBH） and specific gravity were the most important pa- rameters for heritability and genetic gain, respectively. The minimum heritability was reported for vessel element length and genetic gain for fiber length. The populations were grouped into six clusters, cluster II had maximum number of populations （14） and clusters IV and VI had one population each. GBH contributed maximum of 34.39 % towards total divergence followed by specific gravity （14.02%）. An economic technique to produce quality seed by establishing seed orchards with genetically divergent parents was suggested. The hybridization among the populations selected from diverse clusters could produce greater heterosis needed for higher growth and suitable wood and paper manu- facturing parameters.
基金Supported by the National Natural Science Foundation of China(71171103)Specialized Research Fund for the Doctoral Program of Zhanjiang Normal University(ZL1110)
基金Supported by the Natural Science Foundation of Guangdong Province (Grant No. S2012040007369)the Distinguished Young Talents in Higher Education of Guangdong (Grant No. 2012LYM 0089)the National Natural Science Foundation of China (Grant No. 71171103)
文摘In this paper, we study the two-parameter maximum likelihood estimation （MLE）problem for the GE distribution with consideration of interval data. In the presence of interval data, the analytical forms for the restricted MLE of the parameters of GE distribution do not exist. Since interval data is kind of incomplete data, the EM algorithm can be applied to compute the MLEs of the parameters. However the EM algorithm could be less effective.To improve effectiveness, an equivalent lifetime method is employed. The two methods are discussed via simulation studies.
