Sequence analysis of Maturase K (matK): A chloroplast-encoding gene in some selected pulses

The application and utilization of sequence data has been found very informative in the characterization and phylogenetic relationship of different crops species. This study aimed to use bioinformatics tools to characterize the matK gene in some  selected legumes with special reference to pigeon pea [cajanus cajan (L.)Millsp]  matK sequence as a quarry sequence. Nucleotide and amino acid sequence of matK gene of 10 legumes were retrieved from NCBI database and analysed for homology, physiochemical properties, motifs, GC content as well as phylogenetic relationships. Results showed that the nucleotide and amino acid sequence lengths of this gene among the selected legumes differs. Its nucleotide length varied between  631-1580bp, while the amino acids sequence varied between 21 and 509 residues. P. tetragonolobus matK and C. cajan matK sequences had percentage identity of 88% while V. sativa had the lowest percentage identity of 70%. G.tomentella and P. tetragonolobus matK sequence shared the same percentage similarity of 91% with C.cajan while V. sativa had the least (78%) with C.cajan. The motif predicted were tyrosine kinase phosphorylation site, N-myristoylation site, N-glycosylation site, protein kinase phosphorylation site, casein kinase II phosphorylation site and cAMP- and –cGMP dependent protein kinase phosphorylation site. However,  microbodies C-terminal targeting site was only predicted in the amino acid  sequence of matK gene of P. sativum and C.cajan. Phylogenetically, two major clades were revealed with P.sativum, V.sativa, and C. arientinum matK gene sequence in clade A and matK gene sequence of P.tetragonolobus, C. cajan, G. tomentella,  P.vulgaris, V.unguiculata, V. angularis and V. radiate in clade B. It showed that clade A diverged from the ancestry legume approximately 39MYA while legume  sequences in clade B diverged from the ancestor about 57MYA. GC content of the nucleotide sequence of matK gene of V. sativa was highest (31.37%) with the range in the selected legume varying between 7.29%-31.37%. The secondary structure of amino acids sequence of matK gene in the selected legume revealed the alpha helix (34.14%-41.27%), extended strand (11.56%-20.99%) and random coil (39.48%- 51.76%). The major domain architecture found in the amino acid  sequence were single and double types. Implicitly, though maturase K gene  sequences in the selected legumes differ in lengths physiochemical properties, GC content and motif. The result of this study revealed that C.cajan matK gene sequences is closely related to that of P. tetragonolobus but distant to V.  unguiculata as well as P. vulgaris.Keywords: Maturase K (matK) gene, bioinformatics, phylogenetics, selected legumes, breedin

Migliori Bonsai e Suiseki 2000

Catalogo del 4° Congresso UBI EBA Congress 2000 "Il Bonsai per l'Europa". Arco (TN) 28-29-30 Aprile 2000. PP 1-89. Edizioni UBI – Aut. Trib. Milano n° 119 del 19.02.199

Segregation for seed weight, pod length and days to flowering following a cowpea cross

Field studies were conducted to evaluate the segregation of the F3 (early generation) and F6 (late generation) families for seed weight, pod length and days to flowering among cowpea inter-sub-specific crosses. A wide range of segregants were provided in this cross and families were highly significantly different in the three agronomic traits studied. The continuous distributions observed for these traits studied in both generations confirms the quantitative nature of inheritance for these traits. Broad sense heritability estimates ranged from 47.8 to 91.1%. Estimates of genetic advance ranged from high to low and were consistent in both generations for all the traits. The F3 and F6 generations were not significantly different in all the three agronomic traits. Intergeneration correlations ranging from 0.35 to 0.49 also revealed strong associations between traits measured in the two generations. A no significant drop was observed between F3 mean and the corresponding F6 mean. This suggests the existence of a good measure of additive and possibly of additive x additive components of variance (which alone are fixable through subsequent inbreeding) although some amount of dominance and duplicate epistasis (which are non-fixable) may also be operative. The results of this study indicate that selection in early generations for superior types is feasible.Des études en champs ont été conduites pour évaluer la ségrégation des familles en F3 (jeune génération) et F6 (génération avancée) quant au poids des graines, la longueur de la gousse et le nombre de jours à la floraison chez des sous-espèces de niébé croisées. Une large gamme de lignées ségrégantes était introduite dans ces croisements et les familles utilisées étaient sensiblement différentes pour les trois caractères agronomiques étudiés. Les distributions continues observées pour ces caractères étudiés au sein des deux générations confirment la nature quantitative du patrimoine héréditaire pour ces caractères. Les estimations générales d'héritabilité se rangeaient entre 47,8 et 91,1%. Les estimations de transferts génétiques allaient des plus basses aux plus élevées et elles étaient constantes au sein des deux générations pour tous les caractères étudiés. Les corrélations entre générations s'est rangées entre 0.35 et 0.49 et montrées aussi les fortes associations entre les caractères mesurés pour les deux générations. Un déclin non significatif était observé entre la moyenne de F3 et son correspondant de F6. Ceci suggère l'existence d'une bonne mesure additive et peut-être de l' additive x additive composante de la variance (fixable pendant le croisement ultérieur) même si certains traits de dominance et de double épistasies (non fixables) pourraient être opérationnels. Les résultats de cette étude montre qu'une sélection parmi les jeunes générations de races supérieures est faisable

SEGREGATION FOR SEED WEIGHT, POD LENGTH AND DAYS TO FLOWERING FOLLOWING A COWPEA CROSS

Field studies were conducted to evaluate the segregation of the F3 (early generation) and F6 (late generation) families for seed weight, pod length and days to flowering among cowpea inter-sub-specific crosses. A wide range of segregants were provided in this cross and families were highly significantly different in the three agronomic traits studied. The continuous distributions observed for these traits studied in both generations confirms the quantitative nature of inheritance for these traits. Broad sense heritability estimates ranged from 47.8 to 91.1%. Estimates of genetic advance ranged from high to low and were consistent in both generations for all the traits. The F3 and F6 generations were not significantly different in all the three agronomic traits. Intergeneration correlations ranging from 0.35 to 0.49 also revealed strong associations between traits measured in the two generations. A no significant drop was observed between F3 mean and the corresponding F6 mean. This suggests the existence of a good measure of additive and possibly of additive x additive components of variance (which alone are fixable through subsequent inbreeding) although some amount of dominance and duplicate epistasis (which are non-fixable) may also be operative. The results of this study indicate that selection in early generations for superior types is feasible