Evaluation of peanut genotypes for resistance to Tomato spotted wilt virus by mechanical and thrips inoculation

Abstract

-The objective of this work was to evaluate the reactions of three peanut breeding lines and ICGV 86388) to Tomato spotted wilt virus (TSWV) by mechanical and thrips inoculation, under greenhouse conditions, and compare them to the reactions of cultivars SunOleic, Georgia Green, and the breeding line C11-2-39. TSWV infection by mechanical inoculation was visually assessed using an index ranging from 0 (no symptoms) to 4 (apical death). Enzyme-linked immunosorbent assay was used to confirm TSWV infection from both mechanical and thrips inoculations. IC-10, IC-34, ICGV 86388, and C11-2-39 were more resistant than the cultivars SunOleic and Georgia Green based on mechanical inoculation. Upon thrips inoculation only IC-34 and ICGV-86388 were infected by TSWV, as demonstrated by reverse transcription polymerase chain reaction (RT-PCR), although no symptoms of infection were observed. The peanut breeding lines IC-10, IC-34, and ICGV 86388 show higher level of resistance to TSWV than cultivar Georgia Green considered a standard for TSWV resistance.Index terms: Arachis hypogaea, TSWV, mechanical transmission, thrips transmission. Avaliação de genótipos de amendoim em relação à resistência ao Tomato spotted wilt virus por meio de inoculação mecânica e por tripesResumo -O objetivo deste trabalho foi avaliar as reações das linhagens de amendoim IC-10, IC-34 e ICGV 86388 quanto à resistência ao Tomato spotted wilt virus (TSWV), por meio de inoculação mecânica e por tripes, em casa de vegetação, e compará-las às reações das cultivares SunOleic, Georgia Green e da linhagem C11-2-39. A infecção de TSWV após inoculação mecânica foi visualmente avaliada, utilizando-se escala de notas que variam de zero (sem sintomas) a quatro (morte apical). A análise pelo teste ELISA confirmou a infecção de TSWV em ambos os tipos de inoculação. As linhagens IC-10, IC-34, ICGV 86388 e C11-2-39 foram mais resistentes do que as cultivares SunOleic e Georgia Green, com base nos resultados da inoculação mecânica. Em relação à inoculação por tripes, apenas IC-34 e ICGV 86388 foram infectadas por TSWV, conforme demonstrado pela reação em cadeia da polimerase com transcrição reversa (RT-PCR), embora nenhum sintoma de infecção tenha sido observado. As linhagens IC-10, IC-34 e ICGV 86388 mostram maior resistência ao vírus, quando comparadas à Georgia Green, considerada padrão de resistência ao TSWV.Termos para indexação: Arachis hypogaea, TSWV, transmissão mecânica, transmissão por tripes.

Genetic analysis of resistance to watermelon bud necrosis orthotospovirus in watermelon [Citrullus lanatus (Thunb.) Matsum & Nakai]

“…Further, they can tolerate a delayed chemical spray interval and may contribute to significant reduction in chemical inputs. Such a slower disease progress was earlier observed in peanut against GBNV (Kesmala, and Kesmala et al., ) and TSWV (Nascimento et al., ), in cucumber against cucumber mosaic virus (Munshi et al., ) and in okra against okra yellow vein mosaic virus (Seth, Chattopadhyay, Dutta, Hazra, & Singh, ). Further, in the experiment it was also observed that the P1, F 1 , F 2 and BC1 showed a higher plant survival and vine length compared to P2, BC2 and checks for both the crosses.…”

“…TSWV (Nascimento et al, 2006), in cucumber against cucumber mosaic virus (Munshi et al, 2008) and in okra against okra yellow vein mosaic virus (Seth, Chattopadhyay, Dutta, Hazra, & Singh, 2017). Further, in the experiment it was also observed that the P1, F 1 , F 2 and BC1 showed a higher plant survival and vine length compared to P2, BC2 and checks for both the crosses.…”

Losses caused by Groundnut ringspot tospovirus in peanut crop in the State of São Paulo

“…The following parameters were evaluated at each sampling unit: number of plants per meter (stand), number of plants with symptoms of the disease, and a scoring scale of visual symptoms of the disease. The scale used to evaluate the severity of symptoms of TSWV was proposed by Lyerly et al (2002) and Nascimento et al (2006) and adapted for GRSV, where 1 was assigned for plants without symptoms, 2 for leaves with symptoms of yellowing, mosaic, and/or chlorotic spots, 3 for plants with symptoms of yellowing, mosaic and/or chlorotic spots, and height reduction), and 4 for chlorotic plants and stunting ( Figure 1). From the stand and percentage of plants with virus, sampling units were classified as 1) stand with failures and with a high virus incidence (WF+WV); 2) with failures and no virus (WF+NV); 3) no failures and with virus (NF+WV) and; 4) no failures and no virus (NF+NV), being the percentage of plants with virus and stand analyzed again.…”

Tropical Food Legumes

“…Thrips feeding and survival were suppressed on some resistant genotypes compared with susceptible genotypes. In Brazil, three peanut breeding lines (IC-1, IC-34, and ICGV 86388) showed resistance to TSWV under glass house and field tests (Nascimento et al, 2006).…”