Effect of Temperature on Symptoms Expression and Viral RNA Accumulation in Groundnut Bud Necrosis Virus Infected Vigna unguiculata

Abstract

Background: Groundnut bud necrosis virus (GBNV) (Tospovirus genus, Bunyaviridae family) infects the major crops of solanaceae, leguminosae and cucurbitaceae in India. Temperature is an important factor which influences the plant growth and development under diseased conditions. Objective: In the present study, we evaluated the effect of four different temperatures on the symptoms expression and viral RNA accumulation in the GBNV inoculated cowpea plants. Material and Methods: For the evaluation of viral symptoms and RNA accumulation, we used 2-3 leaf stage cowpea plants grown in the controlled conditions. GBNV was mechanically inoculated by sap method to the cowpea plants and inoculated plants were incubated at four different temperatures (30, 25, 20 and 15 °C). Results: The first visible symptom of GBNV infection at the inoculated site was observed in the form of chlorotic spots which were converted into the necrotic spots as the infections succeeded. Some yellow mosaic symptoms were also observed at the systemic site during viral infection cycle. Plants incubated at higher (30 and 25 °C) temperatures showed a severe necrosis and a higher viral RNA accumulation at the inoculated site and facilitated the viral spread at the systemic site. However, viral RNA accumulation was less at the systemic site than the inoculated site. In contrast, symptoms' expression and viral RNA accumulation were decreased at the inoculated site at low (20 and 15 °C) temperatures, no viral symptoms were observed at the systemic site (15 °C); in addition to viral RNA accumulation suppression at this site. GBNV infection at the inoculated site induced the higher accumulation of H 2 O 2 followed by the induction of cell death at higher temperatures (30 and 25 °C) than the lower (20 and 15 °C) temperatures. Conclusion: This study suggests that viral RNA accumulation parallels with the H 2 O 2 production and induction of cell death by GBNV infection in cowpea plants is temperature dependent.

Impact of Abiotic Stresses on Plant Virus Transmission by Aphids

“…Plant signalling pathways and responses to various abiotic stresses are partly shared with those induced by viral infection, and the fact that they can interfere with one another is not a novel concept (see [86] and references therein). The effect of abiotic/biotic plant stresses on viral accumulation through the hijacking of plant signalling and defence pathways has received much recent attention [86][87][88][89]. Plant abiotic stress sensing, likely through the Ca 2+ signalling pathway, was shown for the potyvirus PVA [86].…”

Effects of Elevated Temperature on the Susceptibility of Capsicum Plants to Capsicum Chlorosis Virus Infection

“…The effects of elevated temperatures on tospovirus symptomatology have shown to vary, depending on different combinations of tospoviruses and their host p species [56,57,62]. For example, the spread and symptom severity of GBNV in cow plants increased at higher temperatures (30 and 25 °C) compared to 20 and 15 °C [56 higher temperatures, the viral titer and RNA of GBNV, as well as hydrogen peroxide els, were increased in inoculated leaves (at 4 and 8 dpi) and systemic leaves (at 24 which resulted in severe necrosis [56]. Similarly, more severe symptoms were observ TSWV-infected Nicotiana tabacum, Physalis ixocarpa, and Datura stramonium at higher perature (29/24 °C, day/night) compared to 23/18 °C, day/night [54].…”

“…Tomato spotted wilt virus (TSWV) infection in tomato shows a higher replication at 20 • C, while symptoms are more severe at 36 • C [54,55]. GBNV infection in cowpea only shows a severe necrosis at higher temperatures (30 • C and 25 • C) but not at 20 • C and 15 • C [56]. On the contrary, the systemic infection of impatiens necrotic spot virus (INSV) in capsicum plants (C. annuum, C. chinense PI152225, and C. chinense PI159236) was completely blocked when they were kept at a constant elevated temperature of 33 • C [57].…”

Effects of dendrobium polysaccharides on human brain microvascular endothelial cell injury induced by ox-LDL via regulating the miR-378 expression

“…In genetics, gene expression is one of the most important fundamental issues that help a genotype to appear as a phenotype. In fact, the genetic code stored in the DNA strands is interpreted by gene expression, and the characteristics and expression of the gene will cause a phenotype in the organism (31)(32)(33)(34)(35).…”