Studies on gene frequencies of polyembryony and karyotype in fluted pumpkin (telfairia occidentalis hook. f.)

Project Abstract

<p> Five experiments were performed to investigate the<br>polyembryonic expressions and karyomorphology of fluted pumpkin<br>(Telfairia occidentalis Hook. F.). The results obtained revealed three<br>morphotypes of polyembryony which included twin, triple and<br>quadruple, irrespective of the shape of the pod. The three<br>morphotypes had side shoots that varied in length. Some were<br>unequal, a few of them were almost equal, and many had<br>rudimentary side shoots, which subsequently degenerated with time.<br>Chi-square test between the pod shape and the embryo type depicted<br>independence (χ2= 1.02; P= 0.90) between pod shape and the embryo<br>type. The triple and quadruple embryo types had the highest and<br>lowest frequencies of occurrence, respectively. The gene frequencies<br>in the first year were 0.64 and 0.36 for polyembryony (S allele) and<br>monoembryony (s allele), respectively. The derived zygotic frequencies<br>were 0.41 for the homozygous dominant (SS); 0.46 for the<br>heterozygous (Ss) and 0.13 for the homozygous recessive (ss). These<br>summed up to 0.87 for the multiple embryonic traits and 0.13 for the<br>single embryonic trait. In the second year, the zygotic frequencies for<br>the homozygous dominant (SS), the heterozygous (Ss) and the<br>homozygous recessive (ss) were 0.33, 0.49 and 0.18, respectively.<br>These corresponded with the 0.82 for the multiple embryonic traits<br>and 0.18 for the single embryonic trait. Chi square analysis showed<br>that the gene frequencies in both years did not differ significantly (χ2=<br>0.017; P= 0.96). The results obtained from the cytological studies of<br>fluted pumpkin revealed the interphase and mitotic stages of the cell<br>cycle, and a diploid chromosome number of 2n = 22. There were<br>traces of polyploids namely; aneuploids (2n = 22 + 1), triploid (3n =<br>Five experiments were performed to investigate the<br>polyembryonic expressions and karyomorphology of fluted pumpkin<br>(Telfairia occidentalis Hook. F.). The results obtained revealed three<br>morphotypes of polyembryony which included twin, triple and<br>quadruple, irrespective of the shape of the pod. The three<br>morphotypes had side shoots that varied in length. Some were<br>unequal, a few of them were almost equal, and many had<br>rudimentary side shoots, which subsequently degenerated with time.<br>Chi-square test between the pod shape and the embryo type depicted<br>independence (χ2= 1.02; P= 0.90) between pod shape and the embryo<br>type. The triple and quadruple embryo types had the highest and<br>lowest frequencies of occurrence, respectively. The gene frequencies<br>in the first year were 0.64 and 0.36 for polyembryony (S allele) and<br>monoembryony (s allele), respectively. The derived zygotic frequencies<br>were 0.41 for the homozygous dominant (SS); 0.46 for the<br>heterozygous (Ss) and 0.13 for the homozygous recessive (ss). These<br>summed up to 0.87 for the multiple embryonic traits and 0.13 for the<br>single embryonic trait. In the second year, the zygotic frequencies for<br>the homozygous dominant (SS), the heterozygous (Ss) and the<br>homozygous recessive (ss) were 0.33, 0.49 and 0.18, respectively.<br>These corresponded with the 0.82 for the multiple embryonic traits<br>and 0.18 for the single embryonic trait. Chi square analysis showed<br>that the gene frequencies in both years did not differ significantly (χ2=<br>0.017; P= 0.96). The results obtained from the cytological studies of<br>fluted pumpkin revealed the interphase and mitotic stages of the cell<br>cycle, and a diploid chromosome number of 2n = 22. There were<br>traces of polyploids namely; aneuploids (2n = 22 + 1), triploid (3n = <br></p>

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