Graduate Thesis Or Dissertation

 

Response of Roughstalk Bluegrass (Poa trivialis L.) to Waterlogging Stress Public Deposited

Downloadable Content

Download PDF
https://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/dn39x434k

Descriptions

Attribute NameValues
Creator
Abstract
  • Roughstalk bluegrass (Poa trivialis L.) (RB) is a weed species that increased very quickly in grass seed production fields of the Willamette Valley. The invasion of RB in grass seed crops often occurs in waterlogged soils. In waterlogged areas, RB exhibited better competitiveness and had greater population densities than other grass species. Oxygen deficiency is the major environmental stress caused by waterlogging. Studies were conducted to investigate the physiological characteristics that potentially contribute to the better waterlogging tolerance of RB. Oxygen deficiency resulted in a germination delay in both RB and tall fescue (Festuca arundinacea Schreb.) (TF) species, but the delay for TF was greater than for RB. Higher temperatures (20 and 30 C) increased the influence of oxygen deficiency on TF, but did not influence the effect of oxygen deficiency on RB. In a greenhouse study, 28 days of waterlogging during the early establishment stage reduced the aboveground biomass of RB and TF by 58 and 46%, respectively, but did not influence seedling numbers. Alcohol dehydrogenase (ADH) activity in both RB and TF seedlings increased under anoxic treatment. After 4 weeks of waterlogging treatment, the leaf number and plant height were reduced more in TF than in RB. The leaf number was reduced by 32 and 30% in TF and RB, respectively. The plant height was reduced by 42 and 35% in TF and RB, respectively. The root dry biomass was reduced by 43 and 13% in TF and RB, respectively. The root length increased 6% in waterlogged TF, and decreased 42% in waterlogged RB. Compared to TF, RB root system was shallower after four week long waterlogging treatment. At 1, 2, 3, and 4 weeks after treatment, ADH activity in root of mature plants increased 93, 45, 39, and 57% in waterlogged TF, and increased 56, 27, 22, and 23% in waterlogged RB. At 1, 2, 3, and 4 weeks after treatment, lactate dehydrogenase (LDH) activity in roots of mature plants increased 15, 18, 13, and 13% in waterlogged TF, and 2, 19, 5, and 11% in waterlogged RB. The turf quality, aboveground biomass, photosynthetic capacity, and water soluble carbohydrate concentrations were reduced by the waterlogging treatment, but the reductions were not different between RB and TF. RB has a larger root aerenchyma areas than TF. After a four week waterlogging treatment, the aerenchyma by area portions were 23 and 34% in drained and waterlogged TF roots, and 29 and 38% in drained and waterlogged RB roots. Root porosities increased in both waterlogged TF and RB, but the increases were not different between TF and RB. After a four week waterlogging treatment, the root porosities were 25 and 31% in drained and waterlogged TF plants, and 23 and 30% in drained and waterlogged RB plants. Physiological characteristics including quicker seed germination, lower oxygen required during establishment, a thicker and shallower root system, lower fermentation under low oxygen stress, and larger aerenchyma areas may contribute to better waterlogging tolerance in RB.
License
Resource Type
Date Available
Date Issued
Degree Level
Degree Name
Degree Field
Degree Grantor
Commencement Year
Advisor
Committee Member
Academic Affiliation
Non-Academic Affiliation
Subject
Rights Statement
Publisher
Peer Reviewed
Language
Replaces

Relationships

Parents:

This work has no parents.

In Collection:

Items