Abstract/Details

An investigation of the relationships between mineral nutrition and the phytoextraction of zinc by Indian mustard (Brassica juncea Czern.)


2002 2002

Other formats: Order a copy

Abstract (summary)

Zinc is the heavy metal occurring in the greatest concentrations in the majority of wastes in modern, industrialized communities and is a common metal found at metal-polluted sites. Phytoextraction is a plant-based remediation technology aimed at the removal of metals from contaminated sites through the use of metal-accumulating plants. Although Indian mustard (Brassica juncea Czern.) has been identified as a moderate accumulator of Zn, little is known about the Zn-phytoextraction potential of this plant and whether or not mineral nutrition could be used to improve plant growth and Zn accumulation under Zn-contaminated conditions. The objectives of this research were to determine how the Zn phytoextraction potential of B. juncea is affected by: (a) the concentration of Zn in the nutrient medium; (b) the alleviation of Zn-induced Fe deficiency; (c) the molar % ratio of NH 4+ to NO3 and (d) the concentration of N and P in the nutrient medium. The pH of nutrient solutions generally decreased with: increasing Zn supply; decreasing Fe supply; and increasing proportion of NH4+-N in nutrient solutions. The ability of B. juncea to phytoextract Zn increased with increasing Zn supply initially, but then leveled off because the increase in shoot Zn concentration was accompanied by a suppression of shoot growth. Zinc-induced Fe deficiency was found to limit the effectiveness of B. juncea to phytoextract Zn, and increased P fertility appeared to exacerbate this problem. Alleviating Fe deficiency with root applied Fe-EDDHA had a limited effect on increasing Zn phytoextraction because Zn accumulation was suppressed with increasing Fe supply. Plants concentrated more Zn in shoots and roots if plants were supplied a high proportion of NO3, and increasing NH4+ nutrition enhanced growth. Zinc phytoextraction was maximized if plants were supplied 90% NO3-N and 10% NH4 +-N. Zinc accumulation in shoots increased with increasing N and P supply, but the effect of N was greater. To the extent that N was a limiting factor for growth, N additions increased plant growth, but growth was not effected by P nutrition. Increased N fertility can increase Zn phytoextraction, but the effect of P nutrition is limited.

Indexing (details)


Subject
Environmental science;
Agronomy;
Botany;
Environmental engineering
Classification
0768: Environmental science
0285: Agronomy
0817: Botany
0775: Environmental engineering
Identifier / keyword
Health and environmental sciences, Applied sciences, Biological sciences, Brassica juncea, Indian mustard, Mineral nutrition, Phytoextraction, Zinc
Title
An investigation of the relationships between mineral nutrition and the phytoextraction of zinc by Indian mustard (Brassica juncea Czern.)
Author
Hamlin, Russell Lawrence
Number of pages
139
Publication year
2002
Degree date
2002
School code
0118
Source
DAI-B 63/06, Dissertation Abstracts International
Place of publication
Ann Arbor
Country of publication
United States
ISBN
9780493715087, 0493715088
Advisor
Barker, Allen V.
University/institution
University of Massachusetts Amherst
University location
United States -- Massachusetts
Degree
Ph.D.
Source type
Dissertations & Theses
Language
English
Document type
Dissertation/Thesis
Dissertation/thesis number
3056234
ProQuest document ID
275611842
Copyright
Database copyright ProQuest LLC; ProQuest does not claim copyright in the individual underlying works.
Document URL
http://search.proquest.com/docview/275611842
Access the complete full text

You can get the full text of this document if it is part of your institution's ProQuest subscription.

Try one of the following:

  • Connect to ProQuest through your library network and search for the document from there.
  • Request the document from your library.
  • Go to the ProQuest login page and enter a ProQuest or My Research username / password.