AVOCADO - Tropical Fruits - page 170

cultivars are 'Booth 7', 'Booth 8', 'Collinson', 'Hall' and 'Hickson', while late-
season cultivars are 'Lula', 'Monroe', 'Choquette', 'Booth 3' and a few others
(Table 7.4). A similar situation occurs in Hawaii, where a large number of
cultivars are grown, including introductions from California, Florida, Australia
and Mexico and selections of local origin. 'Sharwil', an Australian cultivar, has
become a leading cultivar, with a recent release, 'Green Gold', increasing in
acreage. Puerto Rico and the Dominican Republic cultivate some of the Florida
cultivars along with some locally developed cultivars, such as the West Indian-
Guatemalan hybrids 'Semil' and 'Gripiña'.
Mexico grows 'Fuerte' and ''Hass' as the main cultivars, along with other
California and Florida ones. The 'Criollo' is mentioned as a selection of the
Mexican race and is well adapted to median ecological areas of Mexico (Diaz-
Avelar, 1979). Besides Mexico, Brazil has developed a substantial industry,
mostly with introduced cultivars, such as 'Fuerte', 'Hass', 'Carlsbad', 'Corona',
'Edranol', 'Nabal' and 'Ryan', and cultivars of local origin, such as 'Solano',
'Ouro Verde', 'Quintal' and 'Fortuna'.
In Australia, 'Hass' and 'Fuerte' have been planted most frequently,
especially along the coastal areas of northern New South Wales and southern
Queensland. 'Sharwil', a local selection (Guatemalan-Mexican hybrid), has
gained considerable popularity, although in some areas it had fl uctuating
yields. Under tropical conditions in the Northern Territory, the Mexican
and Guatemalan cultivars yield poorly (Sedgley et al. , 1985). South African
production is largely from 'Hass' and other California cultivars. Israel's
production was initially based on California cultivars, until an intensive
selection programme over the years produced a large number of local
cultivars, such as 'Ettinger' and 'Horshim'.
In Asia, the avocado has not attained the popularity it has in other areas,
although it was introduced into Malaysia over 120 years ago. In Indonesia,
avocado grows well at 200-1000 m on well-drained soils, and trees are
generally propagated by seeds. In the Philippines, many cultivars have been
introduced from the USA since 1903, and avocado is grown in nearly all parts
of the country, although it has not attained the popularity of other fruit.
CULTURAL PRACTICES
Propagation and nursery management
Avocado is primarily propagated commercially by budding or grafting upon
seedling rootstocks. However, the variability of seedling populations with
respect to certain desirable characteristics, such as resistance to Phytophthora
root rot and tolerance to salinity and calcareous soils, has posed problems
(Ben-Ya'acov and Michelson, 1995). Seedling production has largely changed