Avocado Production in Asia and the Pacific - United Nations in ...

Though avocado was introduced into the country a long time ago, its production is
still small compared to other tropical fruits such as mango, longan, rambutan and durian, due
to various reasons. At present, the avocado is not grown in monoculture and it is rarely
found grown under intensive care on an orchard scale. It is observed to be used increasingly
as an intercrop or as a shade tree for coffee, other than in mixed culture in fruit plantations,
or as a backyard crop, primarily for domestic use .
Because it is not considered a main crop, cultural techniques are often neglected.
There has been no varietal improvement work reported since 1967 except a collection of
avocado varieties that are maintained at Hung Loc Agriculture Research Center, Dong Nai
province, by Professor V.C. Hau. The harvesting and handling techniques are poor, fruits
are often picked prematurely and do not give their best quality. Thus, avocado fruit prices are
not stable and often are very low compared to other tropical fruits.
However, the avocado has recently received the attention and interest of the
government agricultural departments as well of the research institutions, primarily due to its
high nutritive value. A research network under the collaboration of various horticultural
research institutions, which is coordinated by SOFRI, has been set up to focus on surveys
and clonal selection which includes avocado, durian, longan, mango, pommelo, grape and
lychee.
3. PRODUCTION OF PLANTING MATERIAL
Seedlings are the most popular type of planting material used in the country. Farmers
sow the seeds which are selected from good mother trees . The seedlings prepared by the
farmers for their own use are sometimes exchanged among local farmers. As a result, the
tree and fruit characters are highly variable in the local avocado population. Seedlings also
have a further disadvantage as the avocado is polyembryonic and could produce plants from
genetic embryos which are always heterogeneous, causing more variability.
Some Vietnamese documents describe the advanced propagation methods on
avocado which are currently practised only in horticultural research stations for research
purposes. Since the advanced methods of plant propagation have been well and widely
practised in the country to produce millions of plants for other fruit crops, it can be explained
that the problem in avocado planting material production is not due to technical problems but
to other constraints such as the low price for the fruit.
4. ESTABLISHMENT OF ORCHARDS
Most avocado orchards are in the highlands of southern Vietnam where the natural
conditions are favourable for its performance. However, water sources for irrigation are
scarce and rainfall is not well-distributed throughout the year. To support the development of
young plants, often the planting season starts from the onset of monsoon rains during the
months of June and July. At one time, the few monocrop avocado orchards were planted
with a density of 160 - 200 trees/hectare at the spacing of 6 x 10 metres or 6 x 8 metres. But
when avocado was no longer considered as the main crop, the original density was later
reduced by thinning to allow for the development of a main crop like coffee, durian,
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