Agriculture Reference
In-Depth Information
Sometimes a selection is elevated to a cultivar status by satisfying only a few
of the above characteristics (Table 9.3). Such a selection is 'Grof ', by virtue
of consistent bearing over a 7-year period, producing fl owers usually several
weeks later than other Chinese cultivars grown in Hawaii and producing
aborted seeds in about 95% of the fruit. Average fruit size is 12.5 g, smaller
than other Chinese cultivars grown in Hawaii, but there is approximately 20%
more edible aril for the same weight of fruit (Storey
et al.
, 1953).
Breeding for adaptation of cultivars to the higher temperature conditions
in the warm tropics is an important criterion (Menzel, 1983). Menzel and
Paxton (1986a), using glasshouses at high temperatures (30°C day/25°C
night) to evaluate litchi seedlings for low vigour, found this to be a useful
technique for initial screening prior to fi eld evaluation of adapted genotypes
that would fl ower and fruit under warm conditions. The rate of fl ushing in
the glasshouse at high temperatures agreed with the relative vigour and
consistency of fl owering of the parent cultivars in the fi eld.
Similar criteria have been developed for longan (Table 9.3). Longan fruit
criteria include retention of total soluble solids after harvest, crisp and smooth
fl esh, good taste, uniform size and high aril content.
Cultivars
According to Grof (1921), Chinese nurserymen recognized the dii culties in
perpetuating the desirable characteristics of highly regarded cultivars under
conditions other than those in which the fruit originated. The environment
profoundly infl uences cultivar characteristics, and this may explain the large
number of cultivars, with 74 cultivars mentioned in Wu Ying Kuei's list of very
ancient origin. Among the many known cultivars in China, the cultivars 'San
yue hong' ('Sum Yee Hong'), 'Shui dong' ('Souey Tung'), 'Fe zi xiao' ('Fay Zee
Siu'), 'Hei ye' ('Haak Yip'), 'Gui wei' ('Kwai May'), 'No mi ci' ('No Mai Chee')
and 'Huai zhi' ('Wai Chee') in Mandarin, with the Cantonese in brackets,
are most widely grown (Table 9.4). Sixty-seven cultivars and selections are
described for Guangdong, with 26 of these being major commercial cultivars
(Anon., 1985). 'Brewster' ('Chen Zi', 'Chen Family Purple') trees are vigorous,
large and one of the faster-growing cultivars. 'Hei Ye' has been observed to be
a slow grower, low by comparison to cultivars such as 'Chen Zi' and 'Gui Wei'
of the same age but becomes spreading.
Cultivars in Thailand are 'Da zao', 'Hei ye', 'Huai zhi' and 'Hong huey'
(syn. 'Mau mong') (Table 9.4). Other cultivars are 'Kim cheng', 'Hong thai',
'Ohia' (syn. 'Ouw', 'Hei ye', 'Baidum'), 'Gui wei', 'Grof ', 'No mi ci', 'Chen zi'
and 'Mauritius'. In Australia, the cultivars most often planted are 'Da zao',
'Bengal', 'Hei ye', 'Huai zhi' and 'No mi ci'. In the USA, Florida cultivates
primarily 'Brewster', 'Mauritius' and 'Sweet Clif '. The 'Mauritius' in Hawaii
is dif erent from the Florida 'Mauritius'. In Hawaii, most of the plantings
