Fusarium root rot is a major limiting factor in snap bean (Phaseolus vulgaris L.) production. The level of genetic resistance in commercial bean cultivars is minimal and disease is frequently exacerbated by environmental factors. We investigated the contribution of vigorous, adventitious roots to enhancing root rot tolerance in snap bean. Seedling root system architecture was evaluated in 17 recombinant inbred lines (RILs) from a cross of a resistant snap bean line (FR266) and a susceptible dry bean cultivar (Montcalm). The RILs varied in tolerance to Fusarium root rot. Although overall length and branching density (as measured by fractal dimension and meristem numbers) of root systems were not related to root rot resistance, the lateral root number at the root: shoot interface was positively correlated with genotype tolerance (R 2 = 0.6*). Root diameter was also positively correlated with tolerance; this is consistent with the hypothesis that larger adventitious and basal roots are beneficial under disease stress. A field-based study of commercial snap bean cultivars compared raised and flat-bed systems of production, in a soil inoculated with Fusarium solani f. sp. phaseoli. Substantially greater yields (40% to 90%) were observed in raised beds. Root vigor was relatively high (root length density >0.2 cm·cm−3) and root rot scores were lower with raised than with flat-beds, in 2001, but not in 2000. Overall, this is suggestive that integrated crop management practices can improve lateral root vigor and reduce root rot severity.
S. Snapp, W. Kirk, B. Román-Avilés, and J. Kelly
A.A. De Hertogh and L.B. Gallitano
Dutch-grown Hippeastrum bulbs (`Apple Blossom' and `Red Lion') were packed in five readily available and economical packing systems and after transport and storage were evaluated as flowering potted plants. After being harvested and graded, bulbs were specially packed and placed in perforated cardboard boxes, shipped by boat to Raleigh, N.C., and stored in the original packing materials for 84 days at 48 °F (9 °C). At planting time, the best old basal root system and lowest disease incidence for both cultivars was obtained when bulbs were packed with hout-wol, a type of excelsior, in perforated polyethylene bags and placed in perforated cardboard boxes. Plants from bulbs with this system and those packed loose in polyethylene bags flowered the earliest. At full flower, the longest leaves were obtained with the hout-wol, box only, and wood chip systems. There were no significant effects of the five packing systems on floral stalk length, number of flowers produced per stalk, flower diameter, strength of the first floral stalk or leaves, or overall plant quality. After flowering, the root systems were harvested. The hout-wol packing system significantly increased the fresh weights of the old basal roots retained, secondary roots produced, and total weights of the root system. there were significant differences between cultivars. `Apple Blossom' produced fewer roots and lower quality plants (shorter leaves and taller floral stalks) than `Red Lion'. Other significant cultivar differences, e.g., days to flower, were attributed to genetic variation. Based on the most desirable forcing characteristics, the superior packing system for shipping and storing Dutch-grown Hippeastrum bulbus was hout-wol combined with perforated polyethylene bags.
Martin Makgose Maboko and Christian Phillipus Du Plooy
) reported that transplants produced higher late and total yields than direct-seeded plants for one of two watermelon ( Citrullus lanatus Thunb.) cultivars. Transplants of bell pepper ( Capsicum annuum L.) resulted in increased basal roots, advanced
Daniel S. Egel, Ray Martyn, and Chris Gunter
; NeSmith, 1999 ; Olson et al., 1994 ). It is possible that basal roots, i.e., roots that emerge from the upper portion of the tap root, are favored by surface-applied nutrients and water during crop production ( Nicola, 1998 ), whereas transplant
Senay Ozgen, James S. Busse, and Jiwan P. Palta
, M.E. Vaughan, B.E. 1968 Relation between simultaneous Ca and Sr transport rates in isolated segments of vetch, barley, and pine roots Plant Physiol. 43 1913 1918 Kratzke, M.G. Palta, J.P. 1986 Calcium accumulation in potato tubers: Role of the basal
James S. Busse, Senay Ozgen, and Jiwan P. Palta
, J.P. 1986 Calcium accumulation in potato tubers: Role of the basal roots HortScience 21 4 1022 1024 Marry, M. Roberts, K. Jopson, S.J. Huxham, I.M. Jarvis, M.C. Corsar, J
Thomas Björkman and Stephen Reiners
Soil Sci. Soc. Amer. J. 78 319 324 Bonser, A.M. Lynch, J. Snapp, S. 1996 Effect of phosphorus deficiency on growth angle of basal roots in Phaseolus vulgaris New Phytol. 132 281 288 Bravo, P. Uribe, E.G. 1981 Temperature dependence of the concentration
Arthur Villordon, Jeffrey C. Gregorie, and Don LaBonte
( Miller et al., 2003 ). Cumulative evidence from maize ( Zea maize ) ARs, common bean basal roots, and white clover ( Trifolium repens ) lateral roots supports the hypothesis that low Pi increases ethylene sensitivity in plants ( Song and Liu, 2015 ). We