000 02252nam a2200241Ia 4500
008 220216s9999 xx 000 0 und d
100 _aNyaka Ngobisa A.I.C
245 0 _aCharacterization of Pestalotiopsis microspora, the casual agent of rubber leaf blight disease in Cameroon
260 _bRubber Science
_c2018
300 _a112-120
520 _aHevea brasiliensis is the only commercial source of natural rubber in Cameroon and its production can be severely limited by diseases such as leaf blight. The disease is mostly observed in smallholder rubber fields in SOuth West Cameroon. For this study, leaf samples were collected from infected plants. The pathogen was then isolated and identified as Pestalotiopsis microspora following the cultural and morphological characterisation of colonies developed from single spore isolates. Culture media, period of incubation, temperature and pH affected the mycelial growth of P. microspora. Inoculation on detached leaflets revealed the pathogenic capacity of this fungus. Re-isolation of the pathogen from the symptoms produced confirmed Kochs postulates. Molecular sequence analysis of the internal transcribed spacer (ITS) region 1 and 2 including 5.8S rDNA (ITS-5.8S-ITS2) confirmed the morphological identification. P. microspora was therefore identified as the causative agent of the leaf blight on rubber in South West Cameroon. The effects of some fungicides were tested in vitro on mycelial growth of P. microspora. Banko plus (Chlorothalonil 550 g L-1 + Carbendazim 100 g L-1), Penncoz (Mancozeb 800 g kg-1) and Metalm 72 WP (Cuprous oxide 600 g kg-1 + Metalaxyl 120 g kg-1) tested at different concentrations revealed inhibitory activity in vitro. Among these fungicides, a marked efficiency of Chlorothalonil + Carbendazim was observed, though the inhibition of mycelial growth was more effective with Cuprous oxide + Metalaxyl at rates: 100, 75 and 50 per cent only.
650 _aInternal transcribed spacer
650 _aLeaf blight
650 _aNatural rubber
650 _aPathogenicity
650 _aPestalotiopsis microspora
700 _aDoungous O
700 _aEhabe E.E
700 _aGodswill N
700 _aNjonje S.W
700 _aOwona N.P.A
942 _cJS
999 _c55439
_d55439