The fate of surface roots of citrus seedlings in dry soil

K. R. Kosola, David Eissenstat

Research output: Contribution to journalArticle

46 Citations (Scopus)

Abstract

The top portions of the root system of deeply rooted plants are frequently in dry soil while deeper roots still have access to water. We expected that many surface roots would be shed when subject to localized soil drying. We further hypothesized that the cost of fine root construction per unit root length would be negatively correlated with the rate at which root length is shed. Seedlings of four citrus root- stocks that varied widely in specific root length (cm g-1 root) were used to test these hypotheses. Plants were grown for 4 months in a split-pot system divided into a top and bottom pot. After roots were well established in the bottom pot, water was withheld from the top pots of half of the plants; plants were harvested every 2 weeks thereafter. Sufficient water was supplied to the bottom pot to prevent shoots of droughted seedlings from experiencing significant water stress. All plants were labelled with 14CO2 48 h before harvesting, and autoradiographs made of the fine roots harvested from the droughted compartment. Comparisons of the autoradiographs with digitized images of the root system allowed us to assess root mortality and root sink activity. As expected, the proportion of 14C-labelled photosyrithate allocated to fine roots in the top pot declined with soil drying in all four genotypes; however, there was no genotypic effect on this decline. Contrary to our expectations, extensive root mortality was not apparent for any genotype, even after 60 d of localized soil drying. Apparently, selection for rapid shedding of roots in response to soil drying has not occurred in these Citrus species.

Original languageEnglish (US)
Pages (from-to)1639-1645
Number of pages7
JournalJournal of experimental botany
Volume45
Issue number11
DOIs
StatePublished - Nov 1 1994

Fingerprint

Citrus
Seedlings
Soil
seedling
Roots
Drying
Soils
seedlings
soil
Water
Genotype
fine root
drying
Mortality
Dehydration
autoradiography
root system
Root System
root systems
genotype

All Science Journal Classification (ASJC) codes

  • Ecology, Evolution, Behavior and Systematics
  • Plant Science
  • Physiology
  • Statistics, Probability and Uncertainty
  • Ecology
  • Applied Mathematics

Cite this

@article{df3cdd57d95f473996bd5b3bece18eb2,
title = "The fate of surface roots of citrus seedlings in dry soil",
abstract = "The top portions of the root system of deeply rooted plants are frequently in dry soil while deeper roots still have access to water. We expected that many surface roots would be shed when subject to localized soil drying. We further hypothesized that the cost of fine root construction per unit root length would be negatively correlated with the rate at which root length is shed. Seedlings of four citrus root- stocks that varied widely in specific root length (cm g-1 root) were used to test these hypotheses. Plants were grown for 4 months in a split-pot system divided into a top and bottom pot. After roots were well established in the bottom pot, water was withheld from the top pots of half of the plants; plants were harvested every 2 weeks thereafter. Sufficient water was supplied to the bottom pot to prevent shoots of droughted seedlings from experiencing significant water stress. All plants were labelled with 14CO2 48 h before harvesting, and autoradiographs made of the fine roots harvested from the droughted compartment. Comparisons of the autoradiographs with digitized images of the root system allowed us to assess root mortality and root sink activity. As expected, the proportion of 14C-labelled photosyrithate allocated to fine roots in the top pot declined with soil drying in all four genotypes; however, there was no genotypic effect on this decline. Contrary to our expectations, extensive root mortality was not apparent for any genotype, even after 60 d of localized soil drying. Apparently, selection for rapid shedding of roots in response to soil drying has not occurred in these Citrus species.",
author = "Kosola, {K. R.} and David Eissenstat",
year = "1994",
month = "11",
day = "1",
doi = "10.1093/jxb/45.11.1639",
language = "English (US)",
volume = "45",
pages = "1639--1645",
journal = "Journal of Experimental Botany",
issn = "0022-0957",
publisher = "Oxford University Press",
number = "11",

}

The fate of surface roots of citrus seedlings in dry soil. / Kosola, K. R.; Eissenstat, David.

In: Journal of experimental botany, Vol. 45, No. 11, 01.11.1994, p. 1639-1645.

Research output: Contribution to journalArticle

TY - JOUR

T1 - The fate of surface roots of citrus seedlings in dry soil

AU - Kosola, K. R.

AU - Eissenstat, David

PY - 1994/11/1

Y1 - 1994/11/1

N2 - The top portions of the root system of deeply rooted plants are frequently in dry soil while deeper roots still have access to water. We expected that many surface roots would be shed when subject to localized soil drying. We further hypothesized that the cost of fine root construction per unit root length would be negatively correlated with the rate at which root length is shed. Seedlings of four citrus root- stocks that varied widely in specific root length (cm g-1 root) were used to test these hypotheses. Plants were grown for 4 months in a split-pot system divided into a top and bottom pot. After roots were well established in the bottom pot, water was withheld from the top pots of half of the plants; plants were harvested every 2 weeks thereafter. Sufficient water was supplied to the bottom pot to prevent shoots of droughted seedlings from experiencing significant water stress. All plants were labelled with 14CO2 48 h before harvesting, and autoradiographs made of the fine roots harvested from the droughted compartment. Comparisons of the autoradiographs with digitized images of the root system allowed us to assess root mortality and root sink activity. As expected, the proportion of 14C-labelled photosyrithate allocated to fine roots in the top pot declined with soil drying in all four genotypes; however, there was no genotypic effect on this decline. Contrary to our expectations, extensive root mortality was not apparent for any genotype, even after 60 d of localized soil drying. Apparently, selection for rapid shedding of roots in response to soil drying has not occurred in these Citrus species.

AB - The top portions of the root system of deeply rooted plants are frequently in dry soil while deeper roots still have access to water. We expected that many surface roots would be shed when subject to localized soil drying. We further hypothesized that the cost of fine root construction per unit root length would be negatively correlated with the rate at which root length is shed. Seedlings of four citrus root- stocks that varied widely in specific root length (cm g-1 root) were used to test these hypotheses. Plants were grown for 4 months in a split-pot system divided into a top and bottom pot. After roots were well established in the bottom pot, water was withheld from the top pots of half of the plants; plants were harvested every 2 weeks thereafter. Sufficient water was supplied to the bottom pot to prevent shoots of droughted seedlings from experiencing significant water stress. All plants were labelled with 14CO2 48 h before harvesting, and autoradiographs made of the fine roots harvested from the droughted compartment. Comparisons of the autoradiographs with digitized images of the root system allowed us to assess root mortality and root sink activity. As expected, the proportion of 14C-labelled photosyrithate allocated to fine roots in the top pot declined with soil drying in all four genotypes; however, there was no genotypic effect on this decline. Contrary to our expectations, extensive root mortality was not apparent for any genotype, even after 60 d of localized soil drying. Apparently, selection for rapid shedding of roots in response to soil drying has not occurred in these Citrus species.

UR - http://www.scopus.com/inward/record.url?scp=0000667237&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0000667237&partnerID=8YFLogxK

U2 - 10.1093/jxb/45.11.1639

DO - 10.1093/jxb/45.11.1639

M3 - Article

VL - 45

SP - 1639

EP - 1645

JO - Journal of Experimental Botany

JF - Journal of Experimental Botany

SN - 0022-0957

IS - 11

ER -