Agriculture Reference
In-Depth Information
Lemon trees are very vigorous and thorny, having an upright habit that becomes
more spreading when the tree matures. Leaf morphology is variable depending on
the tree vigour, generally being large, ovate, with serrated margins. Newly devel-
oping leaves and flowers are purple but as they develop become green and white,
respectively. Petiole is reduced and even non-existent. Fruit shape varies from
spherical to elliptical, has a characteristic apical nipple at the stylar end, variable in
size, and even nearly non-existent, depending on the cultivar, and develops a necked
stem-end also cultivar-dependent in size. Lemon fruit are high in acidity (5-7 %) and
low in total soluble solids (7-8 %), and is moderately seeded or seedless. Fruit can
be storage for long periods under controlled temperature and humidity conditions.
'Eureka' (Fig.
6.1g
) is the most important cultivar in the Sicilian group. It is of
great importance in California (USA) and Australia, and is also grown in Israel,
South Africa and Spain. Trees have a less densely foliated spreading canopy and
are less frost-hardy than other cultivars. Fruit are moderate to small-sized, ovate
with a moderate apical nipple, and has high juice content with a high acid level.
The rind is smooth to coarse in texture, thin, and, sometimes, develops
puffing
.
Seeds are few, less than five, and often the fruit is seedless. 'Lisbon' is important
in Argentina, Australia, California (USA) and Uruguay. Trees are densely foliated.
Fruit is of excellent quality, has a pronounced nipple, and fewer than nine seeds.
'Lisbon' produces superior yields than 'Eureka' and has denser foliage that protects
the tree from wind and frost damage to the fruit. Fruit harvest periods occur over
winter and spring.
'Verna' is the major cultivar of Spain (50 % of crop). Its origin is unknown. The
trees flower twice and can also produce a third crop; however, only the first one
(February-July; NH) is of commercial quality. It is of medium to large fruit with a
pronounced nipple and a well-developed neck. The rind is medium thick and rough.
The pulp is tender, and the juice content is lower than other cultivars but of good
acidity; fruit have few seeds.
Femminello
comprises a group of selections, 'Comune' ('Ovale'), 'Santa Te-
resa', and 'Siracusano' being the most important ones. It is the most extended type
of lemon grown in Italy, accounting for about 75 % of total crop. Collectively, this
group is harvested all throughout the year.
Femminello
selections are productive;
produce fruit of medium size, moderate thick rind, and lower juice content than
other cultivars but with higher acidity. Seeds number varies upon the crop, prob-
ably because the bees' habit, from 2 to 12,
primofire
and
limoni
having the larger.
Femminello
selections are very susceptible to
mal secco
disease (
Phoma tracheiph-
ila
), a severe tracheomycotic disease of citrus.
Limes
Lime trees probably originated in the tropical Malay Archipelago. They are the
most freeze-sensitive of all commercial citrus species and, thus, its grown is limited
to the tropics and warm, humid subtropical regions of the world.
