|MIAO, HONGQUIN - Institute Of Plant Protection - China
|DI, DIANPING - Institute Of Plant Protection - China
|LU, YINGUI - Institute Of Plant Protection - China
|TIAN, LANZHI - Institute Of Plant Protection - China
|ZHANG, AIHONG - Institute Of Plant Protection - China
Submitted to: Journal of Phytopathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/28/2014
Publication Date: 11/28/2014
Citation: Miao, H., Di, D., Lu, Y., Tian, L., Zhang, A., Stewart, L.R., Redinbaugh, M.G. 2014. Efficient inoculation of rice black-streaked dwarf virus to maize using Laodelphax striatellus Fallen. Journal of Phytopathology. DOI:10.1111/jph.12350.
Interpretive Summary: Every year, virus diseases cause more than $60 billion in crop losses world-wide and it is estimated that up to 3% of the maize crop is lost due to virus diseases. Maize rough dwarf disease (MRDD) is one of the most important diseases of maize in Northern China. The disease is caused by Rice black streaked dwarf virus (RBSDV). All popular maize cultivars in the region are susceptible to the virus, and changing cultivation practices have led to increases in populations of the insect vector that transmits the virus (Laodelphax striatellus). The most economically viable and environmentally sustainable approach for controlling MRDD is to deploy virus-resistant maize cultivars. However, transmitting RBSDV to maize under field or controlled conditions requires the insect vector, making the identification and characterization of resistant germplasm very difficult. In this study, we developed a method for inoculating RBSDV into maize using L. striatellus under controlled conditions that produced 100% infection in virus-susceptible maize cultivars. This method will greatly improve our ability to identify virus-resistant maize lines, to map the virus resistance in these lines and to develop MRDD-resistant maize.
Technical Abstract: Maize rough dwarf disease (MRDD) caused by Rice black-streaked dwarf virus (RBSDV) is the most important viral disease of maize in China. Although deploying disease resistant hybrids would be the most effective way to control the disease, development of resistant hybrids has been limited by virus transmission rates that are too low for effective screening. An efficient screening technique for RBSDV was developed using the vector Laodelphax striatellus Fallen, in which a virus-free planthopper colony was developed and viruliferous planthoppers were obtained by allowing a 3 to 4 day acquisition access period on RBSDV-infected wheat plants. Planthoppers were then allowed a 25 to 28 day latent period on wheat seedlings followed by a 3-day inoculation access period on two-to-three leaf stage maize seedlings. By 35 days post inoculation, susceptible inoculated maize hybrid ‘Zhengdan 958’ and maize inbred lines of ‘Ye 107’ and ‘Ye 478’ plants showed 100% RBSDV infection with systemic symptoms of stunting plants, darkening leaves, and white waxy swellings on the underside of leaves. At the late tasseling stage, average disease indices were from 96.4% to 100.0%. Enzyme-linked immunosorbent assays were correlated with the presence of symptoms. The high efficiency of RBSDV transmission obtained using this technique provides a reliable procedure to screen for RBSDV resistance in maize.