Sugar Beet Cultivar Evaluation for Storability and Rhizomania Resistance

Abstract

To reduce storage losses and improve resistance to rhizomania caused by Beet necrotic yellow vein virus (BNYVV), studies were initiated to establish a storage cultivar selection program. In 2006 and 2007, 30 or more commercial sugar beet (Beta vulgaris) cultivars were grown in soil naturally infested with BNYVV. At harvest, two root samples from each plot were collected and used to establish percent sugar. Additional samples were placed on top of an indoor pile (set point 1.7°C) and inside an outdoor pile in a randomized complete block design with four replications. After 142 and 159 days in indoor storage, sucrose reduction ranged from 13 to 90% in 2007 and 57 to 100% in 2008. Outdoor storage sucrose reduction ranged from 13 to 32% in 2007 and 28 to 60% in 2008. An average of 31 and 45% of the root surface was covered with fungal growth in 2007 and 2008, respectively. Cultivars that retained the most sucrose had resistance to BNYVV and the least fungal growth and weight loss. Indoor storage with BNYVV-infested roots allowed for the most consistent cultivar separation and will potentially lead to selection of cultivars for improved storability and rhizomania resistance.

Influence of Harvest Timing, Fungicides, and Beet necrotic yellow vein virus on Sugar Beet Storage

“…More surface root rot was noted on roots from BNYVV-infested fields versus roots from fields with only trace incidences of BNYVV, with the majority of the fungal growth associated with an Athelia-like basidiomycete, although Penicillium and Botrytis spp. were also present frequently (49,51,55).…”

“…One sugar beet disease of primary concern in both the field and storage is rhizomania (42,49,51). Because rhizomania is widespread in many production areas, host resistance to BNYVV is required for a sugar beet cultivar to be approved for production by seed committees in the United States (33,42).…”

“…Because rhizomania is widespread in many production areas, host resistance to BNYVV is required for a sugar beet cultivar to be approved for production by seed committees in the United States (33,42). In addition, BNYVV has been shown to affect sugar beet storage by causing a loss of sucrose (17,49,51). The virus is thought to increase sucrose loss by increasing root respiration (17) or by facilitating microbial growth on the roots that subsequently leads to sucrose reduction (49,51).…”

“…In addition, BNYVV has been shown to affect sugar beet storage by causing a loss of sucrose (17,49,51). The virus is thought to increase sucrose loss by increasing root respiration (17) or by facilitating microbial growth on the roots that subsequently leads to sucrose reduction (49,51). More surface root rot was noted on roots from BNYVV-infested fields versus roots from fields with only trace incidences of BNYVV, with the majority of the fungal growth associated with an Athelia-like basidiomycete, although Penicillium and Botrytis spp.…”

“…Identifying sources of sugar beet resistance and use of cultivars with resistance to storage rots can alleviate losses to rot in storage (10,13,(47)(48)(49). However, given the significant losses currently suffered in storage in Idaho, host resistance and cultivar selection alone are not enough to deal with storage problems (9,12,26,46).…”