TY - JOUR
T1 - On characterizing root function in perennial horticultural crops
AU - Lavely, Emily K.
AU - Chen, Weile
AU - Peterson, K. Aysha
AU - Klodd, Annie E.
AU - Volder, Astrid
AU - Marini, Richard P.
AU - Eissenstat, David M.
N1 - Funding Information:
We thank M. Taylor at Longwood Gardens; J. Davit at Phipps Conservatory; K. Steiner, S. Edelson, and A. Barton at The Arboretum at Penn State; and L. Sheaffer, L. Burkhard, R. Crassweller, D. Smith, B. Keim, M. Boyer, and D. Harner for permitting collection of root samples for this study. We thank N. Grimm and H. You for help processing root samples. We also thank reviewers for their valuable feedback on the text. This work was supported by the USDA National Institute of Food and Agriculture and Hatch Appropriations under Project #PEN04744 and Accession #1023222 and by an Undergraduate Research Award from the College of Agricultural Sciences at the Pennsylvania State University.
Publisher Copyright:
© 2020 Botanical Society of America
PY - 2020/9/1
Y1 - 2020/9/1
N2 - Premise: While root-order approaches to fine-root classification have shown wide utility among wild plants, they have seen limited use for perennial crop plants. Moreover, inadequate characterization of fine roots across species of domesticated perennial crops has led to a knowledge gap in the understanding of evolutionary and functional patterns associated with different fine-root orders. Methods: We examined fine-root traits of common horticultural fruit and nut crops: Malus ×domestica, Prunus persica, Vitus vinifera, Prunus dulcis, and Citrus ×clementina. Additional roots were sampled from 33 common perennial horticultural crops, native to tropical, subtropical, and temperate regions, to examine variation in 1st- and 2nd-order absorptive roots. Results: First-order roots of grape and 1st- and 2nd-order roots of apple and peach were consistently thin, nonwoody, mycorrhizal, and had high N:C ratios. In contrast, 4th- and 5th-order roots of grape and 5th-order roots of apple and peach were woody, nonmycorrhizal, had low N:C ratios, and were thicker than lower-order roots. Among the 33 horticultural species, diameter of 1st- and 2nd-order roots varied about 15-fold, ranging from 0.04 to 0.60 mm and 0.05 to 0.89 mm respectively. This variation generally was phylogenetically conserved across plant lineages. Conclusions: Collectively, our research shows that root-order characterization has considerably more utility than an arbitrary diameter cutoff for identifying roots of different functions in perennial horticultural crops. In addition, much of the variation in root diameter among species can be predicted by evolutionary relationships.
AB - Premise: While root-order approaches to fine-root classification have shown wide utility among wild plants, they have seen limited use for perennial crop plants. Moreover, inadequate characterization of fine roots across species of domesticated perennial crops has led to a knowledge gap in the understanding of evolutionary and functional patterns associated with different fine-root orders. Methods: We examined fine-root traits of common horticultural fruit and nut crops: Malus ×domestica, Prunus persica, Vitus vinifera, Prunus dulcis, and Citrus ×clementina. Additional roots were sampled from 33 common perennial horticultural crops, native to tropical, subtropical, and temperate regions, to examine variation in 1st- and 2nd-order absorptive roots. Results: First-order roots of grape and 1st- and 2nd-order roots of apple and peach were consistently thin, nonwoody, mycorrhizal, and had high N:C ratios. In contrast, 4th- and 5th-order roots of grape and 5th-order roots of apple and peach were woody, nonmycorrhizal, had low N:C ratios, and were thicker than lower-order roots. Among the 33 horticultural species, diameter of 1st- and 2nd-order roots varied about 15-fold, ranging from 0.04 to 0.60 mm and 0.05 to 0.89 mm respectively. This variation generally was phylogenetically conserved across plant lineages. Conclusions: Collectively, our research shows that root-order characterization has considerably more utility than an arbitrary diameter cutoff for identifying roots of different functions in perennial horticultural crops. In addition, much of the variation in root diameter among species can be predicted by evolutionary relationships.
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U2 - 10.1002/ajb2.1530
DO - 10.1002/ajb2.1530
M3 - Article
C2 - 32901939
AN - SCOPUS:85090442524
SN - 0002-9122
VL - 107
SP - 1214
EP - 1224
JO - American journal of botany
JF - American journal of botany
IS - 9
ER -