First report of Curvularia spicifera (≡ Bipolaris spicifera) causing spathe blight and leaf spot disease of pearl millet (Cenchrus americanus) in India

Cenchrus americanus (L.) Morrone (Poaceae), is an important millet crop cultivated mainly in arid and semiarid regions and is a staple food grain for millions of people. During 2021 July surveys in the pearl millet fields in Mysore (12°30'55" N; 76°56'54" E), Karnataka, India, pl...

Ausführliche Beschreibung

Bibliographische Detailangaben
Veröffentlicht in:Plant disease. - 1997. - (2024) vom: 15. Aug.
1. Verfasser: Mahadevakumar, S (VerfasserIn)
Weitere Verfasser: Mahesh, M, Maharachchikumbura, S S N, Lavanya, S N, Rajashekara, H, Prakash, G, Vikas, K, Tarasatyavati, C, Chandranayaka, S
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2024
Zugriff auf das übergeordnete Werk:Plant disease
Schlagworte:Journal Article Causal Agent Crop Type Field crops Fungi Pathogen detection Subject Areas cereals and grains
LEADER 01000naa a22002652 4500
001 NLM376356960
003 DE-627
005 20240816232926.0
007 cr uuu---uuuuu
008 240816s2024 xx |||||o 00| ||eng c
024 7 |a 10.1094/PDIS-04-24-0889-PDN  |2 doi 
028 5 2 |a pubmed24n1503.xml 
035 |a (DE-627)NLM376356960 
035 |a (NLM)39148366 
040 |a DE-627  |b ger  |c DE-627  |e rakwb 
041 |a eng 
100 1 |a Mahadevakumar, S  |e verfasserin  |4 aut 
245 1 0 |a First report of Curvularia spicifera (≡ Bipolaris spicifera) causing spathe blight and leaf spot disease of pearl millet (Cenchrus americanus) in India 
264 1 |c 2024 
336 |a Text  |b txt  |2 rdacontent 
337 |a ƒaComputermedien  |b c  |2 rdamedia 
338 |a ƒa Online-Ressource  |b cr  |2 rdacarrier 
500 |a Date Revised 16.08.2024 
500 |a published: Print-Electronic 
500 |a Citation Status Publisher 
520 |a Cenchrus americanus (L.) Morrone (Poaceae), is an important millet crop cultivated mainly in arid and semiarid regions and is a staple food grain for millions of people. During 2021 July surveys in the pearl millet fields in Mysore (12°30'55" N; 76°56'54" E), Karnataka, India, plants showed spathe blight and leaf spot disease with an overall incidence ranging from 5 - 8% in the 15 hectares surveyed. Infected leaves appeared brown, and lesions extended to the sheath. Some spathes were also found infected with similar symptoms. Diseased leaves and spathes were collected (n = 5 each) for pathogen identification. Samples were cut into small pieces (0.5 cm2), sterilized with sodium hypochlorite (2%, v/v), and blotted dried. The associated fungal pathogen was isolated on potato dextrose agar (PDA) medium amended with Streptomycin (40 mg/L) and incubated at 28 ºC for 1 week. Colonies were grey, fluffy, cottony with an irregular margin, undulate and dark brown in the back of the plate. Conidiophores were pale brown, erect, slightly curved, septate, unbranched, verruculose and measured 27.1 - 94 µm in length × 2.3 - 4.5 µm in width (n = 20). Conidiogenous cells were brown, subcylindrical, irregularly shaped, and conidia were straight, mainly elliptical, dark brown smooth, with two to three septa, with measurements of 11.1 - 26.4 µm by 5.7 - 14.3 µm (n = 50). Based on morphological characters, the pathogen was identified as Curvularia sp. Two representative isolates (UOMPM1 & UOMPM2) were molecularly identified. The total genomic DNA was extracted with a CTAB method, and ITS, GAPDH and tef-1α loci were amplified using primers ITS1/ITS4 (White et al., 1990), GPD1/GPD2 (Berbee et al., 1999) and EF1983F/EF-2218R (Schoch et al., 2009) respectively. ITS sequence had 100% similarity (706/706bp) with reference sequence C. spicifera (MH863648; HF934915 & HF934916); tef-1α sequence had 100% (933/933bp) identity with C. spicifera (KM062878, KJ939505), and the GAPDH sequence was 99.8% identical to that of Curvularia sp. (MG979055), and C. spicifera (MH809681). Combined dataset of concatenated sequence (ITS-GAPDH-tef-1α) was used in a phylogenetic analysis and revealed that the isolates were in a common clade with the isolate of Curvularia spicifera (CBS 274.52) thus, confirming the identity of the isolated pathogen as C. spicifera. The sequences obtained in the present study were deposited in the GenBank (ITS: OQ253406, OQ253407; LSU: OQ253429, OQ253430; GAPDH: OQ263372, OQ263373 & TEF: OQ263374, OQ263375). Pathogenicity test was carried out by inoculating (foliar /whole plant spray) 60 healthy pearl millet plants (45-days old), grown in field plot with spore suspension (105 conidia/ml). Control plants (n=20) were treated with sterile water. The experiments were conducted in triplicates and repeated twice. Development of disease symptoms was recorded on 41 plants, and all control plants remained healthy. The identity was confirmed after re-isolation as C. spicifera based on cultural and molecular sequence analysis. To our knowledge, this is the first report of C. spicifera causing a leaf spot and spathe blight disease of pearl millet in India. This disease seriously affects grain production, and effective disease management strategies need to be investigated 
650 4 |a Journal Article 
650 4 |a Causal Agent 
650 4 |a Crop Type 
650 4 |a Field crops 
650 4 |a Fungi 
650 4 |a Pathogen detection 
650 4 |a Subject Areas 
650 4 |a cereals and grains 
700 1 |a Mahesh, M  |e verfasserin  |4 aut 
700 1 |a Maharachchikumbura, S S N  |e verfasserin  |4 aut 
700 1 |a Lavanya, S N  |e verfasserin  |4 aut 
700 1 |a Rajashekara, H  |e verfasserin  |4 aut 
700 1 |a Prakash, G  |e verfasserin  |4 aut 
700 1 |a Vikas, K  |e verfasserin  |4 aut 
700 1 |a Tarasatyavati, C  |e verfasserin  |4 aut 
700 1 |a Chandranayaka, S  |e verfasserin  |4 aut 
773 0 8 |i Enthalten in  |t Plant disease  |d 1997  |g (2024) vom: 15. Aug.  |w (DE-627)NLM098181742  |x 0191-2917  |7 nnns 
773 1 8 |g year:2024  |g day:15  |g month:08 
856 4 0 |u http://dx.doi.org/10.1094/PDIS-04-24-0889-PDN  |3 Volltext 
912 |a GBV_USEFLAG_A 
912 |a SYSFLAG_A 
912 |a GBV_NLM 
912 |a GBV_ILN_350 
951 |a AR 
952 |j 2024  |b 15  |c 08