Estimates of Genetic Variability for Seedling Traits in Fluted Pumpkin (Telfairia occidentalis Hook. F)

This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. ABSTRACT An experiment was conducted to evaluate genetic variation among twenty-one fluted pumpkin genotypes for seedling traits. The seeds of the fluted pumpkin were germinated in nursery bags filled with saw dust at the Federal University of Agriculture, Abeokuta and the Federal University of Technology, Akure, Nigeria between July and August, 2013. The experiment was laid out in completely randomized design with three replications. Characters evaluated were emergence percentage (E%), emergence index, emergence index rate, vine length (cm), leaf area (cm 2 ), number of leaves, shoot dry weight (g), and seedling vigour index (SVI). Significant (P≤0.05) differences were observed among the fluted pumpkin genotypes for the evaluated characters. High E% was observed for genotypes Ftn45 (94.80%), Ftn43 (93.30%), Ftn57 (93.30%), Fte41 (90.0%), Ftn61 (86.70%), and Ftm11 (83.30%). Also, these genotypes had above average values for SVI. High phenotypic coefficients of variation and genotypic coefficients of variation were observed for leaf area (75.44%) and dry shoot weight (55.85%), respectively while heritability estimates above 50% was observed for leaf area (82.0%), dry weight (77.78%), E% (70.84%), and SVI (51.98%). The genetic advance was high for E% (38.37), SVI (38.09), and leaf area. SVI, E%, vine length, and leaf area had significant positive correlation with most of the traits therefore, they can be used as selection criteria in fluted pumpkin. Therefore, genetic improvement of early seedling can be used for selection programme in fluted pumpkin

Can auxins improve rooting of propagules and establishment of cashew clones?

Introduction. Cashew production has been on a decline due to poor yield resulting from poor quality traits of open-pollinated seedling populations that were used to establish plantations. Clones established from outstanding individuals through air-layering root poorly and are not likely to survive transplanting, thus clonal propagation by air-layering has been of little value for cashew propagation. Materials and method. To improve the rooting percentages of air-layering, three auxins (IBA, NAA and IAA) were applied at six concentrations [(0, 1, 2, 3, 4 and 5)%] on four cashew genotypes. Results and discussion. Significant improvement was recorded in terms of layer take, number of roots per layer, number of days to rooting, length of roots and percentage of surviving clones after transplanting. Improvement varied between the different auxins, concentrations and genotypes. We observed that degree of rooting was genotype-specific and influenced by auxin type and specific concentration. Our data showed that, among the auxins tested, IBA was most effective, with optimum performance at the 2% concentration. Conclusion. Using auxins made it possible to significantly improve the rooting and survival of cashew propagules; however, to achieve sufficient rooting and better establishment after transplanting, auxin treatment should not exceed 3% concentration. This intervention would help alleviate the problem of clonal establishment in cashew

Floral Biology of Fluted Pumpkin (<i>Telfairia occidentalis</i> Hook. F.)

Knowledge of floral biology is essential to crop improvement. Ten genotypes of fluted pumpkin (Telfairia occidentalis) were observed for floral morphology, phenology and insect visitation for two consecutive years. Functional dioecy of fluted pumpkin was confirmed, whereas none of the studied genotypes was monoecious. Floral structures differed significantly among the genotypes. Both male and female flowers were symmetrical, pentasepalous, fimbriate and non-bright pentapetalous, but male flowers were more numerous. Male inflorescences emerged from 11 to 14 weeks after planting and the female flower buds appeared about 4 weeks later. The flowering period of the male flowers was longer than that of female flowers and both gender flowering periods coincided for a specific interval. It took between 11 to 14 days from bud initiation to anthesis and flowering ceased when there were occurrences of successful fruits set. In both gender flowers petals started unfurling at around 6.00 pm and full bloom was achieved by dawn, while petal shrivelled at sun set (between 6.30 pm to 7.30 pm). The anthers dehisced at anthesis of the male flowers; the pollen grains were whitish and sticky. Only the male flowers have nectar and pollen and this may explain infrequent female flowers visitation. Hover flies (Cheilosia species) were the major floral visitors observed