of all larval instars, larvae feeding behavior, pupation, adult morphology, duration of
all stages of development depending on temperature. Research of biology and ecology
show, that this insect develops in three complete generations from April to November.
Its life cycle lasts an average of 61.1 days. Adults are polyphagous and consume many
plants during maturation feeding, the larvae develop in different amaranth species,
browsing the galleries inside the stalks and forming galls [22].
In Sri Lanka, amaranth is grown as a leaf vegetable crop. On the cultivated
amaranth, 92 species of phytophagous insects from 11 orders were found. Among them
four species develop in stalks, particularly three weevil species: Hypolixus truncatulus,
Trichobaris spp., Pantomorus spp. and amaranth borer Amauromyza abnormalis. Total
infestation of amaranth with intra-stalk phyrophagous insects was 92 %, among which
the weevil Hypolixus truncatulus was the most abundant and harmful [19].
On the African continent, amaranth as a vegetable crop is grown both in the
western part – in Nigeria, and in eastern part – in Kenya [7]. In result of study of
cultivated amaranth pests in Nigeria it was found, that the main foliage pests were
caterpillars of Hymenia recurvalis and larvae of mining flies – Liriomyza sp., the main
stalk pest was the weevil Gasteroclisus rhomboidalis, the pests of grain were bugs
Cletus sp. (Coreidae) [4] The harm of phytophagous insects depends on cultivar
features and on the distance between plants [17].
In the past decade, consumption of amaranth has increased in Kenya, this plant is
used both as a leaf and as a grain crop. Demand for amaranth grows here not only due
to the unique nutritional and medical properties of this crop, but also in connection with
the reorientation of Kenya's agriculture in the direction of increasing the production of
leafy vegetables and reducing the dependence on the production of exotic vegetables.
Therefore entomocoenosis of amaranth is actively studied in Kenia, including
phytophagous and zoophagous species. As in Nigeria, the main pests of grain in Kenia
were the bugs (Coreidae) from genus Cletus: C. indicator, C. orientalis, C. capensis,
C. ochraceus; stalks and foliage were damaged by weevils Hypolixus nubilosus and
caterpillars of Hepertogramma bipunctalis. The last species is the pest of stalks and
leaves of amaranth in America (Brazil and Mexico). Pest complex in Kenia forms at
the expense of indigenous and adventitious polyphagous insect species. In the absence
of amaranth, these insects always have an alternative food [14]. In addition to the above
mentioned species, the authors provide a list of foliage amaranth pests. These are
polyphagous species, particularly Spoladea recurvalis (Fabricius, 1775) (Lepidoptera;
Crambidae), Sylepta derogota (Lepidoptera; Pyralidae), Spodoptera littoralis
(Boisduval, 1833) (Lepidoptera; Noctuidae), weevils from Hypolixus genus (H.
truncatulus, H. haerens, H. nubilosus). From miners the amaranth in Kenia is damaged
by Liriomyza huidobrensis Blanchard and Liriomyza sativae (Diptera; Agromyzidae),
which are of American origin and quarantine species for Europe [14]. Dangerous
sucking pests are peach-potato aphid (Myzus persicae), plant bugs (Lygus lineolaris),
and leafhoppers (Empoasca sp.).
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