Cucumber mosaic virus infection of chickpea stands: temporal and spatial patterns of spread and yield‐limiting potential

Abstract

Patterns of spread and yield losses were examined when migrant aphid vectors transmitted Cucumber mosaic virus (CMV) within chickpea ( Cicer arietinum ) plots. When numbers of chickpea plant infection foci were varied to provide initial infection incidences of 0·3-2%, rate of virus spread and its final incidence increased in proportion to initial virus incidence and pathogen progress curves reflected a polycyclic pattern of spread. Chickpea seed yields decreased by 44-45% when CMV incidence reached 61-74% at final assessment in plots with simulated 1-2% initial incidence. In chickpea plots with or without introduced lupin plant infection foci, cumulative spatial data for diseased plants were assessed using spatial analysis by distance indices ( sadie ). When CMV spread within a plot, infection was concentrated in large patch clusters and was consistent with comprehensive localized spread around primary infection foci. When introduced infection foci were absent, there was more diffuse spread with many isolated clusters. In individual plants that developed CMV symptoms at different growth stages, shoot and pod dry weight were reduced by 60-65% and 77-79% (early infection) and 44 and 66% (late infection), respectively. Seed yield losses were 78-80% (early) and 65-67% (late), and reduction in 50-seed weight was 20-25% regardless of time of infection, so seed number was reduced more by early than late infection. Infection also reduced seed quality as, in addition to smaller seed size, seed coats were discoloured and malformed: the proportions of malformed seeds were 9-11% (early), 3-6% (late) and 0·5% (healthy).

Control of Plant Virus Diseases in Cool-Season Grain Legume Crops

“…Losses are generally greatest when plants become infected at vulnerable early growth stages and incidence approaches 100%. Examples of quantitative estimates of seed yield losses from field experiments with natural spread include ones with CMV and BYMV in lupin where yield losses of up to 66% occurred (Bwye, Jones, & Proudlove, 1994;Jones, 2001;Jones, Coutts, & Cheng, 2003), CMV in chickpea where yield losses were up to 80% ( Jones, Coutts, Latham, & McKirdy, 2008), and PSbMV in pea where yield losses of up to 25% occurred (Coutts, Prince, & Jones, 2009). Yield losses from field experiments with other combinations of virus and cool-season grain legume crops are given by Alkhalaf, Kumari, Haj Kasem, Makkouk, and Al-Chaabi (2010), Boswell and Gibbs (1983), Bos et al (1988), Cockbain (1983), Franz, Makkouk, and Vetten (1997), Kraft and Hampton (1980), Kumari and Makkouk (1995), , Makkouk, Kumari, and Bos (1993), and .…”

Effective management of viruses in pulse crops in south eastern Australia should include management of weeds

“…The role of annual weeds and weed seed is less clear. Seed transmission of AMV, CMV, BYMV and PSbMV in a number of pulse crops is well established (Abraham and Makkouk 2002;Makkouk et al 1993;Jones and Coutts 1996;McKirdy et al 2000;Latham et al 2001;Latham and Jones 2001b;Parry and Freeman 2001) and infected pulse seed often provides the primary inoculum for aphids to spread virus within crops (Latham and Jones 2001a;Latham and Jones 2001b;Jones et al 2008;Coutts et al 2009). A survey of chickpea, fababean, field pea and lentil seed used on farm in 1997 in the Wimmera and Mallee regions of Victoria showed that Malva parviflora, Medicago spp., Raphanus raphanistrum, Sonchus spp., and Vicia sativa seeds were common as contaminants in pulse grains (Moerkerk 2002).…”

Incidence du Yam mosaic virus (YMV) et du Cucumber mosaic virus (CMV) sur des variétés de Dioscorea spp. cultivées dans les régions de Bouaké et de Toumodi en Côte d’Ivoire

“…Les pays de l'Afrique de l'Ouest et du Centre contribuent pour plus de 90% à la production annuelle mondiale évaluée à 38 millions de tonnes d'ignames (FAO, 2007 (Odu et al, 2004). En effet, ces deux (2) virus affectent sérieusement les rendements de cette culture (Thouvenel et Dumont, 1990;Asiedu et al, 1998 ;Eni et al, 2008a;Jones et al, 2008 ;Séka et al, 2009). Thouvenel et al (1989) et Kouamé et al (2003) ont montré que dans la zone savanicole de la Côte d'Ivoire, l'incidence du YMV et du CMV diffère de celle observée en zone forestière.…”