Indian peanut clump virus (IPCV) infection on wheat and barley: symptoms, yield loss and transmission through seed

Abstract

Wheat and barley crops were shown to be susceptible to Indian peanut clump virus (IPCV) under field conditions. In wheat, the Hyderabad isolate of IPCV (IPCV-H) induced symptoms resembling the rosette caused by soil-borne wheat mosaic virus, and these were apparent only three weeks after emergence. Early-infected plants were severely stunted and dark green, with chlorotic streaks on the youngest leaves, which turned necrotic as the plants aged; most of these plants died. Late-infected plants were also stunted and were conspicuous in the field because of their dark green appearance as a result of delayed maturity. The virus was detected by ELISA and nucleic acid hybridization in all plants with symptoms. These plants usually produced fewer tillers than healthy ones. Spikes were malformed, often did not emerge from the flag leaf, and they contained few, shrivelled seeds. Grain yield was decreased, on average, by 58%. In barley, IPCV-H caused severe stunting and general leaf chlorosis. As the plants aged, the leaves became necrotic and the few infected plants that reached maturity produced small spikes. IPCV-H antigens were detected by ELISA in every wheat seed from infected plants and the virus was transmitted through wheat seed at a frequency of 0·5-1·3%. Storage at 4ЊC for more than a year did not affect seed transmission frequency. The virus was detected in leaves and roots of seed-transmitted plants. Seed transmission was not detected in barley. The Durgapura isolate (IPCV-D) was detected in wheat crops (cv. RR-21) at 3 different locations in Rajasthan State, India. Infected plants showed reduced growth without any overt symptoms.

Serological Methods for Detection of Polymyxa graminis, an Obligate Root Parasite and Vector of Plant Viruses

“…Fungi cultured on artificial medium were tested at a dilution of 25 µg/ml and mixed with dried healthy sorghum root (75 µg/ml) to approximate the amount of P. graminis sporosori in infected sorghum roots. b * = Single-sporosorus cultures I 1-1 , I [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] , and I 1-229 derived from the isolate I 1 . c Mean absorbance readings at 405 nm as the percentage of that observed for the homologous antigen P. graminis from India isolate I 1 .…”

“…They transmit at least 12 different plant viruses in the genera Benyvirus, Bymovirus, Furovirus, and Pecluvirus (1,30,32). Peanut clump virus (PCV) and Indian peanut clump virus (IPCV) are members of the genus Pecluvirus (40) that affect the production of peanut and monocotyledonous crops in West Africa and in the Indian subcontinent (3,9,40,43). In the absence of cost-effective methods for the management of peanut clump disease (40), it was essential to study its epidemiology with emphasis on identification of the hosts for the virus and P. graminis and their influence on the perpetuation and spread of clump disease.…”

Detection of RNA1 and RNA2 of Soil-borne wheat mosaic virus in winter wheat grown from infected seeds

“…Muszelka were soaked in distilled water on a thin layer of cotton in Petri dishes (20 cm in diameter) and left for 4 days for germination at room temperature. Before germination the seeds were washed with 0.026 M Na 3 PO 4 for 10 min to remove any virus capsid from the surface of the seeds (Delfosse et al 1999). Four-day-old whole seedlings (leaves and roots) were taken for diagnostics.…”

RNA2 of Soil-borne cereal mosaic virus is detectable in plants of winter wheat grown from infected seeds

“…Tanker and Equinox were collected from crops grown on land containing a natural inoculum source of SBCMV in 2001(Budge et al 2003. For direct seed testing, triplicate batches of 20 seed from each cultivar were washed with 0.026 M Na 3 PO 4 : 12 H 2 0 for 10 min to remove any virus capsid from the surface of the seed (Delfosse et al 1999). RNA was extracted using a MagExtractor® Total RNA purification kit (ThermoLabsystems) in combination with a Kingfisher ml magnetic particle separator (ThermoLabsystems) following manufacturer's protocol (Toyobo, Japan).…”

“…However, severe symptoms were evident in the crop from which the seed was harvested, as early as January during the 2001-2002 season (Budge et al 2003). Studies of the inoculum dynamics of Indian peanut clump virus (IPCV) have shown early infection strongly correlates with increases in true seed transmission (Delfosse et al 2002), indeed IPCV has been shown to be seedtransmitted in wheat at 0.5-1.3% (Delfosse et al 1999). Work in Poland identified SBCMV virus particles in the mesophyll cells of rye seeds, suggesting the virus was transmitted at a rate of 3% in rye seed (Garbaczewska et al 1997;Jezewska 1995).…”