Graduate Thesis Or Dissertation

 

Estimators of seed yield and its components in a plant introduction nursery of tall fescue (Festuca arundinacea Schreb.) Public Deposited

Downloadable Content

Download PDF
https://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/v405sd01j

Descriptions

Attribute NameValues
Creator
Abstract
  • The objective of this study was to identify visual or easily measured morphological characters associated with seed yield or its components in a spaced-plant nursery of tall fescue (Festuca arundinacea Schreb.). In 1977, 26 plant characteristics were observed on 210 plants from seven different geographic regions of origin. Each origin was represented by three randomly chosen plant introduction entries with ten plants per entry. Variation among entries was highly significant for all characters and variation among entries within origins was as great as the variation among origins. Simple correlation and multiple regression analyses based on the 21 entry means were used to examine character relationships. Simple correlation coefficients revealed groups of highly associated characters involving seed yield, tiller size, fertility, and spikelets per panicle. Fertility characters, however, differed in their relationships with tiller size characters and 100 seed weight. Fertility index and open-pollinated ratio appeared to be useful fertility measures by their high simple associations with yield and 100 seed weight and their lack of association with tiller number. Spikelet number-to-node slope was highly associated with spikelets/panicle and suggested the need to study the possible use of a rating for the amount of taper of the lower portion of the panicle to estimate the number of spikelets per panicle. Negative associations of tiller number and plant diameter'to various fertility characters, spikelets/panicle, and panicle length illustrated plant compensation mechanisms. Phenotypic ratings and girth measurements were not related with spikelet or fertility characters but were highly associated with tiller number. Girth appeared to be the single most useful character associated with tiller number. Early anthesis dates were associated with higher tiller numbers and seed weights and a reduction in panicle size while later anthesis dates were associated with lighter seeds. Multiple character relationships revealed that the most useful fertility characters were those measuring weight per inflorescence. Five panicle gross weight was the best fertility measure in terms of being the least difficult to measure. Five panicle seed weight was slightly more difficult to measure but its variation accounted for more of the variation in yield. Of the following four fertility characters, fertility index, open-pollinated ratio, seeds/panicle, seeds/spikelet; fertility index seemed to be the most useful as it represented the efficiency of a tiller to convert panicle dry weight into panicle seed weight. Selection for seed yield based upon components could be accomplished using six easily measured characters when either fertility index or open-pollinated ratio was used as the fertility component. Eight easily measured characters were required to select for yield when seeds/ spikelet was used as the fertility component. Selection for seed yield based upon easily measured characteristics showed five panicle gross weight, girth, and panicle length to be most useful for multiple character selection. Selection for short panicle length plants within populations of high five panicle gross weights and girths should result in increased seed yields.
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
Digitization Specifications
  • File scanned at 300 ppi (Monochrome) using Capture Perfect 3.0 on a Canon DR-9050C in PDF format. CVista PdfCompressor 4.0 was used for pdf compression and textual OCR.
Replaces

Relationships

Parents:

This work has no parents.

In Collection:

Items