Germination, Attachment and Development of Striga hermonthica (Del.) Benth Induced by Host and Non-host Crops

Abstract

Striga hermonthica (Del) Benth is a semi-parasitic weed that
reduces yields of sorghum, maize, pearl millet, sugarcane and rice in the
semi-arid tropics. Germination of striga seed is induced by stimulants
exuded by roots of host and non-host plants. The objectives of this study
were to compare the ability of some host and non-host crops to induce
striga seed germination and haustoria formation as well as to confirm the
susceptibility of wheat and barley to infestation. S. hermonthica seeds
were collected from Abu Haraz, Gezira State, Sudan, in 2004/2005, and
their germination on some host and non-host crops was investigated using
root chambers that allow observation of striga underground stages. Striga
seeds germinated with all tested crops. Besides sorghum varieties and
maize, S. hermonthica germinated, attached and developed to complete
striga plants with barley and two cultivars of wheat from Sudan. This is
the first report of S. hermonthica parasitizing wheat and barley in Sudan.
Use of root chambers proved that some leguminous crops were
susceptible to S. hermonthica. Chick pea (Cicer arietinum L.),
phillipesera (Vigna trilobata L.), brown seed cowpea [Vigna unguiculata
(L.) Walp.], hyacinth bean (Lablab purpureus L.), peas (Pisum sativum
L.) pigeon pea (Cajanus cajan L.), faba bean and mung bean induced
seed germination, attachment and development of complete green striga
plants. Soybean, roselle, safflower and sunflower supported germination
and attachment of S. hermonthica, but there was no further development
of the semi-parasitic weed. A natural brownish colouration around the