Rear bees if you want to reap from avocado fruits

By Kamende Godmercy,

Assistant Project officer bee keeping and also an Apiculture specialist

 

Avocado is one of the fruit tree seedlings given out freely by Mount Elgon Tree Growing Enterprise.

Getting good crops of avocados here in Uganda is not always easy and pollination is part of the problem and bees have done a great job in most cases to ease pollination.

But when one thinks of bees, they probably conclude that they only produce  honey. This is not true, bees also indirectly produce a third of the common fruits and vegetables we eat through pollination.

 

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A bee vists an avocado tree flowers 

Avocado growers find it hard to provide a regular supply of fruits because the trees only give good crop every second year. However if we all reared bees avocado production will increase tremendously.

While other fruits have simple ways of flowering and self pollination, avocados are different. Each avocado tree can be covered by almost hundreds of thousands of tiny flowers.

The flowering process is complex and generally occurs over a two day period. Under normal climatic conditions, the flower first opens in the female stage when the stigma (the female part of the flower) is receptive.

 

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Avocado fruits 

The flower closes over night and on the second day the male occurs when the pollen is shed. Overlap between the male and female phases may also occur under certain climatic conditions.

Due to the difference in timing of the female and male stages, therefore a means of transferring pollen from an individual flower to another (with the same tree or adjacent trees) is required. The avocado flower therefore requires a vector to effect pollination which is a necessary first step in the process of fruit set.

A vector is an external agent that is capable of causing the transfer of pollen grains from the anthers (the pollen bearing male part of the flower) to the stigma. Numerous pollen grains need to be deposited into the individual stigmas for the avocado tree to have the potential for a good fruit.

 

The avocado flower is adapted to visitation by most flying insects as is evident by its open morphology and the easy access to the nectar. Therefore flies, wasps, honey bees, stingless bees, bumblebees and other insects are potential pollinators of the avocado flower. To date, the honey bees have been the only commercially introduced pollinator in avocado orchards.

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A demonstration of how to graft an avocado tree seedling

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Grafting an avocado tree seedling

Preparation of bees

For a hive to be able to adequately pollinate fruit blossom, it must be above certain strength in bee numbers. It is fundamentally difficult to build a population of honey bees during cold conditions, particularly if there are no naturally occurring sources of pollen and nectar. Thus to have healthy bees early in the season, for avocado pollination, the preparation and management of bees should be a major priority.

Attractiveness, nutritional value of pollen and nectar

Honey bees visit both female and male stage avocado flowers. Usually they collect nectar from both flower stages and pollen from the male stage. However they sometimes collect pollen only and will not visit the female flowers. The attractiveness of the avocado flower to honey bees is low in comparison to the flowers of numerous species. In many cases, foraging honey bees from hives that were placed in the orchard for pollination purposes abandon the avocado flowers in favor of competing bloom. It is quite evident therefore the avocado flowers are not as well adapted to supply the honey bees, needs when compared to the flowers of many other species.

Availability of bees for pollination

Avocado blossom coincides with a number of nectar producing flowering eucalyptus species that have the potential to provide alternative economic gains for the beekeeper in form of honey crops.

Any serious avocado farmer who wants to make good money must keep bees. The bees not only help in increasing production, sweetness and size of fruits but also produce pure organic honey every 6 months.

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Grafted Avocado tree