caa a22 4500 469042028 CHVBK 20180323132814.0 cr unu---uuuuu 170328e19921101xx s 000 0 eng 10.1007/BF01974462 doi (NATIONALLICENCE)springer-10.1007/BF01974462 Epidemiology of beet necrotic yellow vein virus in sugar beet at different initial inoculum levels in the presence or absence of irrigation: Dynamics of inoculum [Elektronische Daten] [G. Tuitert, Y. Hofmeester] Using field plots where rhizomania had not previously been detected, different inoculum levels of beet necrotic yellow vein virus (BNYVV) were created by application of infested soil. A susceptible sugar beet cultivar (cv. Regina) was grown for two consecutive years (1988 and 1989), in the presence or absence of drip irrigation. In soil samples taken in spring 1989, the different initial inoculum levels of 1988 could be distinguished using a quantitative bioassay estimating most probable numbers (MPNs) of infective units per 100 g dry soil. The first sugar beet crop resulted in a tenthousandfold multiplication of inoculum of BNYVV (viruliferousPolymyxa betae). Mean MPNs of BNYVV ranged from 0.6 and 7 per 100 g soil for the lowest inoculum level to 630 and 1100 per 100 g for the highest level, in plots without and with irrigation, respectively. In spring 1990, MPNs had again increased. In both years, the initial inoculum level of 1988 had a significant linear effect on log-transformed MPNs of BNYVV determined. Log-transformed MPNs for 1990 and 1989 showed a positive linear correlation, despite a decreasing multiplication ratio at higher inoculum levels. Drip irrigation during one or two years enhanced the increase in MPN of BNYVV, which was reflected by the enhancement of multiplication ratios at all inoculum levels. The totalP. betae population was also higher after growing two irrigated crops than after growing two non-irrigated ones. Koninklijke Nederlandse Planteziektenkundige Vereniging, 1992 Polymyxa betae nationallicence rhizomania nationallicence BNYVV nationallicence soil-borne virus nationallicence MPN nationallicence quantitative technique nationallicence bioassay nationallicence polyetic epidemic nationallicence Tuitert G. Sugar Beet Research Institute, P.O. Box 32, 4600 AA, Bergen op Zoom, the Netherlands aut Hofmeester Y. Research Station for Arable Farming and Field Production of Vegetables, P.O. Box 430, 8200 AK, Lelystad, the Netherlands aut Netherlands Journal of Plant Pathology Kluwer Academic Publishers 98/6(1992-11-01), 343-360 0028-2944 98:6<343 1992 98 10658 https://doi.org/10.1007/BF01974462 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF01974462 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Tuitert G. Sugar Beet Research Institute, P.O. Box 32, 4600 AA, Bergen op Zoom, the Netherlands aut NATIONALLICENCE 700 1- Hofmeester Y. Research Station for Arable Farming and Field Production of Vegetables, P.O. Box 430, 8200 AK, Lelystad, the Netherlands aut NATIONALLICENCE 773 0- Netherlands Journal of Plant Pathology Kluwer Academic Publishers 98/6(1992-11-01), 343-360 0028-2944 98:6<343 1992 98 10658 Metadata rights reserved Springer special CC-BY-NC licence nationallicence SWISSBIB 469042028 BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer