| dc.description.abstract | Avocado has gained an immense popularity over the last few decades as a luxurious and
important tropical horticultural crop in the modern world. However, production of avocado
especially for commercial use is not commonly done through growing avocado seedlings to
maturity but rather grafted like most commercial fruit crops, mainly to overcome juvenility.
Even then, Hass avocado cultivar is usually more difficult to successfully graft than any other
commonly grown cultivars. It requires suitable environmental conditions for the successful
establishment of the graft. While environmental conditions are believed to be very crucial in
graft success, grafting techniques have to be taken into account too. The aim of this study was to
evaluate the graft success of Hass Avocado cultivar under nursery and field environmental
conditions. An experiment was carried out where Hass scions obtained from NaFORRI orchard
were grafted onto nursery and field rootstocks using splice and top wedge grafting techniques in
a Complete Randomized Block Design (CRBD). Data were collected on number of days to first
bud sprouts, number of bud sprouts, number of young and green leaves and graft survival
percentages for a period of 4 months. Data were entered in Microsoft excel 2007 and further
analysis conducted in Minitab software. Significant tests were carried out using a two-way
analysis of variance (ANOVA), all statistical tests being performed at 5 % level of significance.
The results indicated that a lower mean number of days taken to first bud sprout (04.11±1.08)
was recorded under field environmental conditions while top wedge grafting techniques gave a
lower mean number of days to first bud sprout (05.90±1.22). Generally, higher graft success in
terms of number of bud sprouts (0.43±0.03), number of young (0.92±0.09) and green leaves
(0.81±0.09) was exhibited under nursery environmental conditions using splice grafting
techniques. Nursery environmental conditions revealed a higher mean survival percentage
(32.41±4.15). Among the grafting techniques, splice grafting technique gave a higher mean graft
survival percentage (10.52±1.63%). Statistically, the recovery time (number of days to first bud
sprouts), graft success (number of bud sprouts, number of young and green leaves) and survival
rate of Hass Avocado Cultivar can be significantly influenced by environmental conditions
(P<0.05) but not by grafting techniques (P>0.05). This study indicates that in order to enhance
grafting success of Hass avocado cultivar, grafts should be made under nursery environmental
conditions using splice grafting technique. Commercial avocado farmers and other tree nursery
operators should be encouraged to graft Hass avocado cultivar under nursery environmental
conditions using splice grafting technique. Further research should be carried out on grafting
Hass under nursery and field environmental conditions within the right grafting season (June to
August) using other grafting techniques. Grafting of Hass avocado cultivar should be done by
experienced grafters to determine if the results of the study will be of any difference from those
of the current study. This is expected to provide a better answer to a better grafting techniques
and environmental conditions for promoting grafting Hass avocado cultivar in Uganda. | en_US |
