Wednesday, May 29, 2019

Essay --

Sporadic surveys during the past 25 years (Meketeand Van den Berg, 2003) indicated that several plant- leechlike nematode genera and species were associatedwith various crops in different areas of Ethiopia. Ac-cording to Abebe and Geraert (1995), taxonomic stud-ies of plant-parasitic nematodes in Ethiopia are almostnon-existent. These authors described four known andone new-sprung(prenominal) species. Recently, Mekete et al. (2008) reportedthe forepart of various species of plant-parasitic nema-todes associated with coffee from Ethiopia and gaveshort descriptions and light microscope photos ofScutellonema paralabiatum Siddiqi et Sharma, 1994, andRotylenchus unisexus Sher, 1965. During 2002, an ex-tensive survey was undertaken in Ethiopia. Eightspecies of various nematode genera were found ofwhich short notes are given. Four species, Rotylenchulusborealis, S. brachyurus, S. clathricaudatum and S. mag-niphasmum are new records for Ethiopia. The survey was conducted during the June-Septem-ber 2002 cropping season. Two hundred samples werecollected from different agro-ecological zones through-out the southern, western and southwestern regions ofthe country (Fig. 1). Samples were taken at a depth of25-30 cm with a spade around the roots of the plants.Three to five soil cores were taken at each sampling site,bulked and a sample of approximately 1 kg was taken tothe laboratory for extraction of the nematodes. Nema-todes were extracted from 200 g soil sub-samples bycombining the Cobbs sieving and decanting orderwith a modified Baermanns funnel method (Hooper,1985a). Nematode specimens were then killed... ... with all the previous descriptions of the species(Sher, 1964 Van den Berg and Heyns, 1973).Scutellonema clathricaudatum Whitehead, 1959. Afew specimens of this species were found associatedwith Acacia sp. at Wendo Genet and maize at Shoboka(Jimma). This species was sooner described from cot-ton in Tanzania (Whitehead, 1959) and subsequently re-ported from various other African countries viz.Cameroon, Ivory Coast, Kenya, Mali, Mozambique,Niger, Nigeria, Senegal, Sierra Leone, South Africa, Su-dan, Uganda and Zare (Whitehead, 1959 Sher, 1964).It has also been identified from Ghana, Guinea-Bissau,Malawi and Zambia by the first author, but this is thefirst report for Ethiopia. Our specimens correspondwell with the original as well as subsequent descriptionsof the species (Whitehead, 1959 Sher, 1964).212

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