Incidence, distribution, and pathogenicity of fungi causing root rot in Idaho long-term sugar beet storage piles

Strausbaugh, C.A. (2018) Incidence, distribution, and pathogenicity of fungi causing root rot in Idaho long-term sugar beet storage piles. Plant Disease. 102(11):2296-2307. 26 October 2018.

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Abstract

Fungal rots in sugar beet roots held in long-term storage can lead to considerable sucrose loss, but the incidence and distribution of fungal rots inside sugar beet piles and pathogenicity for some species is poorly understood. Thus, Idaho sugar beet held in five outdoor and two indoor piles in 2014 and 2015 were investigated. The root surface area covered by fungal growth, and discolored and healthy tissue was assessed in nine one-meter square areas per pile using a stratified random sampling design. Pathogenicity was evaluated indoors via plug inoculation in 2015 and 2016. Botrytis cinerea covered more (P <0.0001) of root surface area (6 to 22%) inside indoor piles than outdoor piles (0 to 3%). No trends were evident for the Athelia-like sp. (0 to 15%) and Penicillium-like spp. (0 to 8%). Penicillium-like isolates were comprised of the following species: 60% P. expansum, 34% P. cellarum, 3% P. polonicum, and 3% Talaromyces rugulosus. Trace levels (<1% of root surface) of other fungi including Cladosporium and Fusarium were evident on roots and in isolations. Based on sample location in a pile there were no trends or differences, but two outdoor piles (OVP1 and OVP2) had more (P <0.0001) healthy tissue (90-96%) than other piles (28-80%). When the pathogenicity tests were analyzed by species, all the species had significantly different (P <0.0001) levels of rot (in mm): B. cinerea (61), P. expansum (35), P. polonicum (31), P. cellarum (28), Athelia-like sp. (21), T. rugulosus (0), and non-inoculated check (0). The OVP1 and OVP2 piles had negligible fungal growth indicating proper storage can be achieved through tarped vent piles.

Item Type:	Article
NWISRL Publication Number:	1639
Subjects:	Irrigated crops > Sugarbeet > Root rots Irrigated crops > Sugarbeet > Storage Irrigated crops > Sugarbeet Irrigated crops > Sugarbeet > Root rots > Fungi
Depositing User:	Users 6 not found.
Date Deposited:	29 Oct 2018 20:19
Last Modified:	29 Oct 2018 20:19
Item ID:	1683
URI:	https://eprints.nwisrl.ars.usda.gov/id/eprint/1683