SEED GERMINATION REQUIREMENTS AND PLANT GROWTH HABIT OF SIX NATIVE OKLAHOMA PRAIRIE GRASSES

• Sponsoring Institution: National Institute of Food and Agriculture
• Project Status: COMPLETE
• Funding Source: HATCH
• Reporting Frequency: Annual
• Accession No.: 0229742
• Project Start Date: Oct 1, 2012
• Project End Date: Oct 30, 2015
• Program Code: [(N/A)]- (N/A)

Recipient Organization
OKLAHOMA STATE UNIVERSITY
(N/A)
STILLWATER,OK 74078

Performing Department
Horticulture & Landscape Architecture

Non Technical Summary
This research will determine germination requirements and methods of breaking dormancy in six native Oklahoma prairie grasses. This information is needed before these grass species can be produced on a large scale for sale to the landscape contracting profession for landscape jobs or to the general public. This research will also investigate rate and methods of spread of seedling plants. This will provide clues as to how the grasses might be vegetatively propagated to maintain characteristics that might be lost through genetic diversity of seed propagation.

Animal Health Component

100%

Research Effort Categories

Basic

(N/A)

Applied

100%

Developmental

(N/A)

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
206	0799	1070	100%

Knowledge Area
206 - Basic Plant Biology;

Subject Of Investigation
0799 - Rangelands and grasslands, general;

Field Of Science
1070 - Ecology;

Keywords

prairie grass

germination

stratification

gibberellic acid

Goals / Objectives
The objectives of this research are to 1) determine pregermination treatments that improve germination rate and percentage of six native Oklahoma grasses: big bluestem (Andropogon gerardii Vitm.), indiangrass (Sorghastrum nutans (L.) Nash), little bluestem (Schizachyrium scoparium (Michx.) Nash), blue grama (Bouteloua gracilis (HBK) Lag. Ex Steud.), sideoats grama (Bouteloua curtipendula (Michx.) Torrey), and river oats (Chasmanthium latifolium (Michx.) Yates), and 2) determine vegetative growth patterns of each species with or without clipping early after emergence (to simulate the feeding of bison). This information might be later used to determine potential vegetative propagation methods for the various grass species.

Project Methods
Objective 1: Determine pregermination treatments that improve germination rate and percentage of six native Oklahoma grasses: big bluestem, indiangrass, little bluestem, blue grama, sideoats grama, and river oats. Experiment 1: Because fire causes heat, one experiment will investigate the effect of heat on germination. Rather than using fire, a more controlled heat source such as an oven or water bath will be used to expose dry seeds or seeds with moisture (in glass or other heat-proof containers) to a series of warm temperatures ranging from about 20 degrees C to 40 degrees C for a short time then seeds will be germinated in a growth chamber under moist conditions at 21 degrees C using a photoperiod consisting of 12 hours of light and 12 hours of darkness. Exposure of the seeds to heat may break the seed hull allowing water to penetrate which can result in leaching of inhibitors and allow the seed to imbibe water. It can also meet a warm requirement, if needed, for germination. Experiment 2: Regardless of whether a heat treatment can be identified that increases seed germination or not, a next step would be to investigate the effect of light vs. darkness and photoperiod length on seed germination. These species are warm season grasses that appear to germinate around mid-summer in nature, thus long days and short nights with warm temperatures may contribute to germination. In this study, we will investigate photoperiods ranging from 12 hours light/12 hours darkness to 14 hours daylight/10 hours darkness. Because some seeds require darkness for germination, a dark treatment will be included at each temperature. Darkness will be accomplished by enclosing the petri dishes in aluminum foil to provide darkness. Germination temperatures will be tested from 20 degrees C to 40 degrees C at 5 degree C intervals. Experiment 3: Exposure of seeds to various periods of time in warm or cold stratification can increase germination percentage and rate. Because the seeds of some of these species are very small and would be difficult to find in substrate, we will roll the seeds in moist paper toweling and then place them in plastic bags for cold or warm stratification. This will allow us to find the seeds and accurately count them into the various treatments and replications for accurate germination counts later. Objective 2: determine vegetative growth patterns of each species with or without clipping early after emergence (to simulate the feeding of bison). While seed production can be very effective and efficient in producing new plants, the genetic diversity that occurs with seed reproduction can result in the loss of desirable characteristics of plants. Nursery growers and consumers prefer consistency in plants, so vegetative propagation is desirable in many species. Thus this part of the study will be conducted in relatively large containers that give the plants plenty of room to spread naturally (minimum of 38-L pot size, larger is preferable). A 3:1:1 pine bark:peat:sand (by vol) substrate amended with controlled release fertilizer (Osmocote 17-7-12, 12 month release) and micronutrients (Micromax) will be used for this study.

Progress 10/01/12 to 10/30/15

Outputs
Target Audience: Nothing Reported Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest?Data collection is complete on germination of native prairie grass seeds given different pregermination treatments. Data analysis has not yet been completed. Thus, results have not been distributed to constituent groups yet. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Seeds of native prairie grasses, big bluestem (Andropogon gerardii Vitm.), indiangrass (Sorghastrum nutans (L.) Nash), little bluestem (Schizachyrium scoparium (Michx.) Nash), blue grama (Bouteloua gracilis (HBK) Lag. Ex Steud.), sideoats grama (Bouteloua curtipendula (Michx.) Torrey), and one grass native to the cross timbers area, river oats (Chasmanthium latifolium (Michx.) Yates) were collected at the end of the 2011, 2012, and 2014 growing seasons. The seeds collected in 2011 were germinated in a growth chamber after receiving various cold stratification periods. Only river oats and big bluestem germinated. Both of these species germinated with all cold stratification periods, but the nonstratified control seeds did not germinate. The seeds of all species collected in 2012 except river oats were exposed to a heat treatment (10 second soak in 80oC water) or no heat treatment then cold stratified for different time periods. Seeds in all species except indiangrass germinated regardless of heat treatment as long as cold stratification was provided. Hulls of half of the river oats seeds were removed and seeds with or without hulls were cold stratified for various time periods. Cold stratified seeds germinated regardless of stratification period.

Publications

Progress 10/01/13 to 09/30/14

Outputs
Target Audience: The target audience is landscape installers, government agencies that oversee landscaped areas such as parks, and consumers. Other interested parties would include those using native grasses to re-establish tallgrass and shortgrass prairie areas. Changes/Problems: None What opportunities for training and professional development has the project provided? The principal investigator has mentored two undergraduate students who have helped treat seeds during the past year. How have the results been disseminated to communities of interest? No dissemination has been done in the past year. What do you plan to do during the next reporting period to accomplish the goals? Complete a final component of the study and then publish a refereed journal article with the results of the research.

Impacts
What was accomplished under these goals? In the past year, no additional information has been generated from that of previous years. We are still working on experimental treatments and will have data generated in the next several months.

Publications

Progress 10/01/12 to 09/30/13

Outputs
Target Audience: This research is primarily applicable to nursery crop producers and landscape managers. Others interested in this information might be extension educators and persons associated with non-profit groups who are interested in re-creating prairie grass ecosystems. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? This project has helped train an undergraduate student about seed germination research. It also provides the opportunity to share research results with others who may be interested in germinating these seed species. How have the results been disseminated to communities of interest? No dissemination has been done in the past year. Further research is needed and planned before dissemination will occur. What do you plan to do during the next reporting period to accomplish the goals? A graduate student has contacted me about starting work on a M.S. degree related to this project. He hopes to start his field work in the summer of 2014. The project would include further investigation of seed germination requirements as well as investigating plant establishment in the field.

Impacts
What was accomplished under these goals? A better understanding of germination requirements of prairiegrass seed species was achieved. We also determined further germination research that needs to be conducted to better understand germination of these species.

Publications