Agriculture Reference
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to 4 hatchlings emerging from the remaining cocoons. According to Cluzeau and Fayolle (1989),
one of the factors that contributes to the high fertility rate of
is because its reproduction
may be facultatively biparental, amphimitic, or uniparental, either by parthenogenesis (Omodeo
1952) or by self-fertilization (Andr and Davant 1972).
D. rubida
Dendrobaena veneta
(Rosa, 1886)
Dendrobaena veneta
is a large species of earthworm with considerable potential for use in
vermiculture that can also survive in soil (Satchell 1983). Although it is not very prolific and
does not grow very rapidly, it is used by a number of vermiculturalists (Edwards 1988; Viljoen
et al. 1991). Of the species that have been considered for vermiculture, it is probably one of the
least suitable species for use in organic waste processing or vermicomposting, although it may
have some potential for protein production systems and for breeding for soil improvement.
is a robust earthworm that can tolerate much wider moisture ranges than
many other species and has a preference for mild temperatures (15 to 25
Dendrobaena veneta
C). Its life cycle can be
completed in 100 to 150 days, and 65 days is the average time to reach sexual maturity. Mean
cocoon production has been reported as 0.28 per day, but the hatching viability is low (20%), and
the mean cocoon incubation period is 42 days. The mean number of earthworms hatching from
each viable cocoon was about 1.10 (Lofs-Holmin 1986; Viljoen et al. 1991, 1992; Muyima et al.
1994).
A
Lumbricus rubellus (
Hoffmeister, 1843)
This
species is found commonly in moist soils, particularly those to which
animal manures or sewage solids have been applied (Cotton and Curry 1980a,b). In surveys of
commercial earthworm farms in the United States, Europe, and Australia, earthworms sold under
the name
Lumbricus rubellus
L. rubellus
were all
E. fetida
or
E. andrei
(Edwards and Bohlen 1996).
has a relatively long life cycle (120 to 170 days) with a slow growth rate
and a long maturation time (74 to 91 days) (Cluzeau and Fayolle 1989; Elvira et al. 1996b). We
estimated the net reproductive rate to be 0.35 hatchlings earthworm
Lumbricus rubellus
week
because of the low
−
1
−
1
cocoon production rate (0.54 cocoons week
), and only one hatchling emerged from each cocoon
(Elvira et al. 1996b). Other researchers have recorded higher cocoon production rates for this
species, ranging from 0.49 (Cluzeau and Fayolle 1989) to 1.75 cocoons week
−
1
(Evans and Guild
−
1
1948).
Its low maturation and reproductive rates suggest that it is not an ideal earthworm species for
vermicomposting, although its size, vigor, and ability to survive in soils could make it of interest
as fish bait or for land improvement. Moreover,
is not an opportunistic species, with
obligatory biparental reproduction (Sims and Gerard 1985), which contributes to its low reproduc-
tive rates.
L. rubellus
T
S
ROPICAL
PECIES
Eudrilus eugeniae
(Kinberg, 1867)
species of earthworm belongs to the Eudrilidae; it is a native African species that
lives in both soils and organic wastes but has been bred extensively in the United States, Canada,
and elsewhere for the fish-bait market, where it is commonly called the African night crawler. It
is a large, robust earthworm that grows extremely rapidly, and it is relatively prolific when cultured.
Under optimum conditions, it could be considered an ideal species for animal feed protein produc-
tion. Its main disadvantages are a relatively narrow temperature tolerance and some sensitivity to
handling.
The
E. eugeniae
Eudrilus eugeniae
can live in soils and has high reproduction rates (Bano and Kale 1988;
