Intraspecific variations in flowering phenology of African pear (Dacryodes edulis (g. Don) H.J. Lam) flowering in south east Nigeria

Abstract

A survey was carried out in two states, six locations of south east Nigeria during the normal flowering period for three (3) consecutive years to evaluate the intraspecific variations in flowering phenology of African pear flowering. The different types of the species growing in the forest, distant and nearby farms, including homesteads were used. 60 trees and 180 flowered branches were sampled for the survey. Parameters collected include time for flowering, number of flower per inflorescence, inflorescence length and number of inflorescence per panicle. Data collected were analysed using analysis of variance, regression and correlation. Standard errors and percentages were calculated where appropriate. Based on the observed floral nature, three distinct African pear tree species were identified – female, male and hermaphrodite trees. The time of flowering varied within and between locations. This ranged from December to March 2013 to 2015 for the period of study. Strong positive relationship exist between inflorescence length and flower per inflorescence. Significant (p<0.05) differences were observed in mean flower per inflorescence and mean inflorescence per panicle in 2015 in Abia state. The mean inflorescence length, inflorescence per panicle and flower per inflorescence were statistically (p<0.05) the same for 2014 and 2015 in Imo State. These ranged from 14.79cm to 18.74cm,
13.81cm to 18.60cm; 4.16 to 5.66; 5.75 to 6.61, 21.40 to 92.71 and 45.66 to 110.18 respectively.
Inflorescence length and inflorescence per panicle were significantly (p<0.05) different in 2013
in Imo State. In terms of the trees flowering circle, African pear can be seen as an annual since
57% to 77% of the trees flower annually, while 23% to 43% flower biennially and triennially. Therefore the survey study discovered that there are variations in floral natures, inflorescence length, inflorescence per panicle, flowering circle, and time of flowering in African pear. This study will be useful for breeding purposes in African pear.