Wisconsin cranberry growers report that fruit production by the cranberry cultivar `Ben Lear' (Vaccinium macrocarpon Ait.) is low in beds with poor drainage, while the cultivar `Stevens' is less sensitive to these conditions. We hypothesized that `Ben Lear' and `Stevens' would differ in their root growth and mortality response to variation in soil water potential. Rooted cuttings of each cultivar were grown in a green-house in sand-filled pots with three different soil water potentials which were regulated by a hanging water column below a fritted ceramic plate. A minirhizotron camera was used to record root growth and mortality weekly for five weeks. Root mortality was negligible (2% to 6%). Whole plant relative growth rates were greatest for both cultivars under the wettest conditions. Rooting depth was shallowest under the wettest conditions. Whole-plant relative growth rates of `Ben Lear' were higher than `Stevens' at all soil water potentials. `Stevens' plants had significantly higher root to shoot ratios and lower leaf area ratios than `Ben Lear' plants, and produced more total root length than `Ben Lear' at all soil water potentials. Shallow rooting, high leaf area ratio, and low allocation to root production by `Ben Lear' plants may lead to greater susceptibility to drought stress than `Stevens' plants in poorly drained cranberry beds.
Dana L. Baumann, Beth Ann Workmaster and Kevin R. Kosola
Shengrui Yao, Ian A. Merwin and Michael G. Brown
Root observations in situ with a rhizotron camera enabled us to compare the performance of apple (Malus ×domestica Borkh.) trees on 3 rootstock clones planted in a New York orchard with a history of apple replant disease. Visual observations were conducted in situ at monthly intervals during 2 growing seasons through minirhizotron tubes for trees grafted onto 3 rootstocks: M.7 (M.7), Geneva 30 (G.30), and Cornell-Geneva 6210 (CG.6210). There were 3 preplant soil treatments (fumigation, compost amendment, and untreated checks) and 2 tree planting positions (within the old tree rows or in the old grass lanes of the previous orchard at this site). Preplant soil treatments and old-row versus grass-lane tree planting positions had no apparent influence on root systems, whereas rootstock clones substantially influenced root growth and demography. New root emergence was suppressed during the first fruit-bearing year (2004) on all 3 rootstock clones compared with the previous nonbearing year (2003). A root-growth peak in early July accounted for more than 50% of all new roots in 2003, but there was no midsummer root-growth peak in 2004. The median lifespan for roots of CG.6210 was twice that of G.30 and M.7 in 2004. Also, CG.6210 had more roots below 30 cm depth, whereas M.7 had more roots from 11 to 20 cm depth. Trees on CG.6210 were bigger, yielded more fruit, and had the highest yield efficiency in the third year after planting compared with trees on G.30 and M.7 rootstocks. Crop load appeared to inhibit new root development and changed root-growth dynamics during the first bearing year, with a resurgence in new root growth after fruit was harvested in October 2004. Rootstock genotype was the dominant influence on root lifespan and distribution in this study, whereas preplant soil fumigation, compost amendments, and replanting positions had little apparent impact on root characteristics despite their influence on above-ground tree growth and yield.
Christina E. Wells and David M. Eissenstat
Fine root lifespan has previously been estimated at 3 to 4 weeks for apple trees growing in England. We used nondestructive belowground imaging technology to investigate the accuracy of this estimate for apple trees growing in central Pennsylvania. Eight root observation tubes (minirhizotrons) were installed beneath each of six 20-year-old `Red Delicious' apple trees on M26 rootstock. Videos of roots growing against the tubes were taken at intervals of 14 to 28 days between October to June, depending on the amount of root activity. Images were used to construct a database of life history information for over 500 individual roots. A flush of fine roots was produced in the early fall, followed by a period of low but constant mortality that lasted through December. Roots that survived to this time were generally maintained throughout the winter and following spring. A second flush of root production occurred in the spring, coinciding with bud burst and flowering. Root mortality was highest in late spring following this flush. In contrast to earlier estimates of apple root lifespan, we found that >30% of the fine roots produced in the fall lived for ≥200 days. Most of these roots developed red-brown pigmentation, a feature that previously has been associated with cortical cell death. However, the ability of these pigmented roots to produce new white laterals in the spring argues against categorizing these as dead roots. The information on root demographics provided by this study adds to our understanding of seasonal carbon and nutrient allocation patterns in apple.
Shengrui Yao, Ian A. Merwin and Michael G. Brown
between orchard GMSs and tree root demography and dynamics about which little has been reported previously. New root emergence and root mortality in relation to environmental factors. Unusually hot and dry weather from mid-June to mid-Sept. 2002 affected
Kevin R. Kosola, Beth Ann A. Workmaster, James S. Busse and Jeffrey H. Gilman
acquisition, carbohydrates, and root demography of poplars Oecologia 129 65 74 Kosola, K.R. Parry, D. Workmaster, B.A.A. 2006 Responses of condensed tannins in poplar roots to fertilization and gypsy moth
Maria P. Fuentealba, Jing Zhang, Kevin E. Kenworthy, John E. Erickson, Jason Kruse and Laurie E. Trenholm
538 Miller, G.L. McCarty, L.B. 1998 Turfgrass rooting characteristics of ‘Palmetto’, ‘FX-10’, and ‘Floratam’ St. Augustinegrasses and ‘Pensacola’ bahiagrass, p. 177–187. Root demographics and their efficiencies in sustainable agriculture, grasslands
Daniel Hargey, Benjamin Wherley, Andrew Malis, James Thomas and Ambika Chandra
‘Floratam’ st. augustinegrasses and ‘Pensacola’ bahiagrass, p. 177–187. In: J.E. Box, Jr. (ed.). Root demographics and their efficiencies in sustainable agriculture, grasslands and forest ecosystems. Springer-Verlag, New York, NY Qian, Y.L. Fry, J.D. Upham
Lisa E. Richardson-Calfee, J. Roger Harris, Robert H. Jones and Jody K. Fanelli
management Univ. Minnesota St. Paul, MN Eissenstat, D.M. Yanai, R.D. 1997 The ecology of root lifespan Adv. Ecol. Res 27 1 60 Espeleta, J.F. Donovan, L.A. 2002 Fine root demography
David M. Eissenstat, Denise Neilsen, Gerry H. Neilsen and Thomas S. Adams
subsequently processed for root demographic information. Information collected from images included date of root initiation ( Wells and Eissenstat, 2001 ). After three field seasons in Oct. 2003, soil core samples (diameter, 7.5 cm) were collected at radial
Jesús Gallegos, Juan E. Álvaro and Miguel Urrestarazu
. 0,232,187 A1. U.S. Patent and Trademark Office, Washington, DC: 01-13 Reid, J. Winfield, D. Sorensen, I. Kale, A. 1996 Water deficit, root demography, and the causes of internal blackening in field-grown tomatoes: ( Lycopersicon esculentum Mill