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Floriculture Environmental and Modeling Research1991 Proposal

Floriculture Environmental and Modeling Research at MichiganState University

Dr. John A. Biernbaum
Dr. Royal D. Heins
1991
SUMMARY

This proposal is a request for second year funding of a project approved

for the first time in 1988. The research is in two general areas. The projects

under the direction of John Biernbaum are to define the changes in irrigation

and fertilization practices that must be adopted if our industry is to

survive increasing environmental regulations and decreasing water resources.

The objectives are to investigate irrigation and fertilization practices

and scheduling, plant pathogen management with recirculated solutions,

root media water and nutrient efficiency, root media pH control, and to

collect information about water sources and water quality. The projects

under the direction of Royal Heins involve research to increase our understanding

of how temperature and light can be used to regulate plant growth. The

objectives include investigating the control of stem elongation by day

and night temperature, modeling the growth and development of poinsettia,

Easter lily and other plants to temperature and light, and developing grower

management tools for scheduling and planning crops.

The research will have both immediate and long term benefits for the

floral industry. Recommendations will be developed to help operators of

both large and small greenhouses manage both the crop root zone and the

greenhouse atmosphere. The goal is to maximize production efficiency and

product quality while minimizing environmental impacts. Information about

limiting water use and preventing ground water contamination will help

the floral industry as environmental regulations force changes in irrigation

and nutritional programs. Information detailing how temperature can be

used for precise control of plant growth will improve plant quality, allow

reliable production of plants to market specifications and reduce the use

of growth regulating chemicals.

INTRODUCTION

The Seeley Conference held annually at Cornell University is designed

to bring together the floriculture industry and researchers to discuss

pressing issues of the day. Floriculture’s Role in Environmental Stewardship

was the issue for discussion for 1989. There is little doubt that defining

floriculture’s role in environmental stewardship is becoming one of the

industries highest priorities. From the presentations and participation

at the conference, it seems that the industry is finally starting to wake

up to the scale and difficulty of the problem before us.

Our industry has a tradition of beautifying the environment through

flowers. This tradition will be meaningless if a public perception develops

that we are contributing to environmental contamination. The Alar reaction

is a good example of how quickly people will turn on a long standing American

tradition. The much respected apple, the one you give to the teacher, the

one that keeps the doctor away, the one used to make apple pie, suddenly

is a symbol of what people perceive is wrong with agriculture. It does

not matter that Alar may pose a much smaller risk than some natural plant

chemicals we regularly ingest. Public perception dictates market decisions.

We in floriculture must remember that B-Nine and Alar are the same chemical.

The political forces which removed Alar from the market could also eliminate

B-Nine and other growth regulating chemicals from the market.

The greenhouse industry in general is ready to implement economically

sound alternatives that will protect the environment. They are waiting

for direction and evidence that the methods proposed will be viable over

the long term. Fertilization and irrigation methods that will limit fertilizer

runoff, methods to reuse or recirculate water and fertilizer so it does

not enter the environment, and methods to control plant height without

using chemicals must be presented to greenhouse operators around the country

in a format that is easy to understand and implement. This is the goal

of our research program as outlined in this proposal.

BACKGROUND

This proposal is a request for second year funding of a project approved

for the first time in 1988. Our original proposal detailed a research program

that would address the objectives outlined for a minimum of five years.

(We have assumed that copies of last years proposal with the background

and literature review outlining the problems of environmental pollution

and regulation of plant growth are available to the R&D Committee and

Trustees.) This proposal outlines accomplishments during the past year,

current projects and planned projects for the coming year. Similar to last

year, we have outlined a broad, programmatic approach to developing,solutions

for problems facing the greenhouse industry.

CWe have submitted under separate cover to the trustees a notebook containing

publications from the MSU Floriculture Program for the 1988-89 academic

year. The two project leaders together with graduate students had a total

of 5 refereed scientific articles and 33 extension and trade press articles.

In addition 25 scientific presentations and 9 grower presentations at national

meetings were made during the past year. The articles and research reports

should thoroughly summarize our accomplishments for the past year.

OBJECTIVES

The research objectives supported by this project are:

1) to develop basic information on factors influencing the growth of

floriculture crops.

2) to develop information which will have immediate impact at the grower/manager

level of floriculture crop production.

3) to solve problems which are of immediate concern and already exist

in commercial floriculture production.

CURRENT AND PROJECTED RESEARCH INVESTIGATIONS - DR. BIERNBAUM

Four specific project areas were outlined in the original proposal.

These four have been combined to three and two additional areas have been

added. Research emphasis over the previous two years has been on subirrigation

with recirculated solutions as a method to stop fertilizer runoff from

greenhouses. Despite the many benefits of subirrigation, this technique

is currently a minor part of US production. Increased use of flood benches

will be slow because of the investment costs. In each of the specific project

areas presented there has been a shift over the past year to give equal

or greater emphasis to topwatering systems compared to subirrigation. The

primary goal is to provide greenhouse operators with methods to limit fertilizer

and water runoff and to improve irrigation and fertilization techniques.

1) Irrigation and Fertilization’Practices and Scheduling. C ri ti c

al evaluation of our fertilization techniques is the best approach to limiting

water and fertilizer runoff from greenhouses. Our objective is to take

a quantitative approach to determine how much water and fertilizer is required

to produce a specific crop and to define how that fertilizer should be

applied over the life of the crop.

Our original proposal last year outlined irrigation and fertilization

practices and scheduling and fertilization with subirrigation and recirculated

.solutions as two separate project areas. Based on the subirrigation experiments

completed at that time it seemed that subirrigation might be distinctly

different from traditional top watering since lower levels of fertilizer

application and lower levels of root media soluble salts were necessary.

Based on the past year of work, we now think the same lower levels of fertilization

and root media soluble salt levels can be used with traditional methods.

Research during the current year documented the effect of leaching on

the amount of fertilizer that must be applied to container plants. Poinsettias

were produced with three fertilizer concentrations applied with subirrigation

or topwatering with four different amounts of leaching. When the low fertilization

rate no low leaching was compared to treatments which applied high concentrations

and leaching rates, there was a ten fold difference in the amount of nitrogen

applied and a 40 fold difference in the amount of nitrogen runoff between

leaching treatments, This is a critical indictment of our current fertilization

methods.

The root media EC levels for the poinsettias produced with lower than

standard fertilization rates applied with top watering but little leaching

were consistently lower than recommended levels but quality was good. In

research during the coming year, our findings must be substantiated under

a range of environmental conditions influencing plant growth rate and water

uptake to test how temperature and light relationships influence fertilizer

requirements, One such experiment has been completed comparing topwatering

and subirrigation of bedding plants grown with 4 fertilizer treatments

under 2 light levels.

During the coming year, we must carefully test the relationship between

growth of specific crops and soluble fertilizer (EC) in the root zone.

This may need to be done for each stage of development for a crop. How

to efficiently change the root media EC from one value to another must

also be developed.

This project will be under the direction of both Dr. Biernbaum and Dr.

Heins. Our goal is to take the information collected and develop a narrow

graphical track or target root media EC for a specific crop and set of

conditions. This system could be refined to work for specific growing conditions

and would be the much needed tool to help growers refine and improve irrigation

and fertilization methods.

2) Plant Pathogens in Recirculated Solutions.

Growers have expressed much

concern about pathogen dispersal with recirculated water. A significant

amount of our time has gone into reviewing the literature and developing

a thorough understanding of the factors influencing the development of

disease organisms and their transmittance with recirculated water. In research

during the current year we evaluated the potential for transfer of Pythium

ultimum in a subirrigation system, Based on the results of that test, two

more experiments are currently underway. Our emphasis is on two species

of Pythium since the hydroponics/NFT literature and researchers in West

Germany that we are cooperating with both support a conclusion that Pythium

and Phytophthora will be the two leading pathogens of concern.

Like the irrigation and fertilization phase of the project, our emphasis

was originally on subirrigation with recirculated solutions. The scope

of the project has expanded to include the recirculation of leachate from

top watered plants. We think this will be a greater problem area for pathogen

transmission than subirrigation with recirculated solutions. There are

many different pathogens and crops to study and we do not expect to be

able to come to any broad conclusions based on this research alone. One

of the goals of this phase of the project has been to get pathologists

working with greenhouse crops around the country interested in this research

and that has been happening in the last three months.

3) Root Media Water and Nutrient Efficiency. The objective of this part

of the project is to identify methods of efficiently keeping water and

fertilizer in the growing container. This can be done through root media

selection, the use of wetting agents and possibly water absorbing gels.

All of these methods would be available to every greenhouse operator.

In research during the current year one large factorial experiment investigating

the effect of root media, pot size, wetting agents and irrigation method

was completed. It has provided a basis for further work in the area of

media components increasing water holding and CEC and the use of wetting

agents. Laboratory work investigating the effect of several factors influencing

capillary water uptake in columns of root media was also completed and

will be continued. A greenhouse experiment is underway testing the effect

of a clay product incorporated in peat media on the amount of nitrate leaching

from a 4 inch mum crop. Because of the total lack of information about

water absorbing gels we have also been collecting information about gels

and will do some testing in the coming year.

4) Root Media pH Management. Many greenhouse operations in the midwest

and other parts of the country use irrigation water with high alkalinity.

To negate the effect of water alkalinity, phosphoric, sulfuric, or nitric

acid are injected in the water. While this is a safe procedure if properly

managed, many growers do not like using the acid. Employee safety is a

concern. The use of acid probably increases the amount of nutrients in

runoff. There are other methods which could greatly reduce the use of acids,

The current.recommendations being made to the greenhouse industry are that

there is one alkalinity level that is right for every grower, This approach

is not the best, but research is needed to develop alternatives.

In research during the current year, we have studied the effects of

different types of lime, water alkalinity, and fertilizer acidity or alkalinity

(nitrogen form) effects on root media pH. The two experiments completed

to date have illustrated the effect of these factors over a 12 week geranium

crop. Continued work in this area could lead to important grower education

and management tool s. Research duri ng the comi ng year wi I 1 test water

and fert1izer effects in different media.

5) Water Sources, Water Quality and Water Treatment. This part of the

20fproject mainly will involve the collection of available information

concerning differences between municipal, well, surface and rain water;

definition of the contaminant, salinity, and alkalinity aspects of water

quality; and a review of water treatment methods. Some of this information

will be available from the water quality work done at Ohio State several

years ago. We have a project in progress this summer comparing seven different

water treatments or water qualities on the rooting of poinsettia cuttings

and subsequent growth after the pinch. This has helped us to develop a

better understanding of water quality and depending on the results of these

experiments we may do more work in this area.

In addition to the research completed, a significant amount of time

has been spent in each of the project areas on reviewing the literature

and collecting information useful to the greenhouse industry. Our intent

is to develop a strong knowledge base or foundation for any changes that

are recommended.

There has also been a substantial increase in grower requests for information

about groundwater and water management practices this year compared to

the previous two years. Grower education is a significant component of

our research. The time spent preparing and presenting information to growers

is significant. One copy of a collection of articles about water management

has been included with the proposal submitted for review. The collection

of articles was prepared for a half-day class on water management for Michigan

greenhouse growers. This is offered as an example of how a careful review

of available information can provide immediate help for growers. Included

in the collection of articles are four articles prepared by Dr. Biernbaum

for the September 1989 issue of Grower Talks magazine. This issue will

be the first ever feature water issue.

CURRENT ACTIVITY AND PROJECTED RESEARCH INVESTIGATIONS - DR. HEINS

Investigations during the past year have addressed the areas described

in the 1988 proposal and investigations in the coming year will continue

in these areas. Investigations will concentrate on the effects of temperature

and light on plant growth. The underlying guideline directing this research

is a quantitatively approach to understanding how plants respond to temperature

and light. The program will have the following elements.

1 Investigations i nto the control of stem elongation by day and night

temperature. We have published information on how the relationship between

day and night temperature influences stem elongation, Briefly, stem elongation

in plants responds to the difference (DIF) between the day and night temperature.

As the day becomes progressively warmer than the night, stem elongation

increases. Conversely, as the day becomes progressively cooler than the

night, stem elongation decreases. This information has become a powerful

tool in the hands of growers attempting to control the height of lilies,

poinsettias, chrysanthemums, as well as many other bedding plant species,

Height control becomes easier while growth regulator costs decrease.

Research during the past year has further defined our understanding

of how plants respond to DIF. Experiments were conducted to determine 1)

how plants respond to warm and cool pulses of temperature during different

parts of the day and night, 2) how different photoperiods affect plant

response to DIF, 3) the effects of red and far red light on plant response

to DIF, and 4) how a wide range of plant species, especially bedding plants,

respond to DIF.

Research during the coming year will be based on the results of these

experiments, especially with respect to enhancement of a negative DIF reduction

in stem elongation with red light and length of photoperiod. With the increased

emphasis on post harvest life of plants in the market channel, we will

determine the effects, if any, of DIF on postharvest life of several flowering

potted plants including poinsettia and chrysanthemum. We have already determined

that a negative DIF has no effect on postharvest life of the Easter lily.

We will continue to maintain a close linkage between our research program

and commercial growers. This allows ideas to be rapidly tested under commercial

conditions.

2) Modeling the growth and development of poinsettia. We have had an

ongoing poinsettia research program for the past several years supported

in part by Paul Ecke Poinsettias. In this program, the response of the

poinsettia to temperature has been modeled. Primary emphasis have been

on flower initiation, stem elongation, and bract development. Many of our

concepts and management systems for implementing DIF have evolved from

this program. For example, absolute plant response to DIF depends on the

actual rate of stem elongation, Immediately after the pinch of a poinsettia

shoot, lateral shoot is slow. Growth rate then increases to some maximum

about four to five weeks after the pinch and then again slows as bracts

color and mature, A large negative or positive DIF either immediately after

pinch or near finish will have only a small impact on final plant height.

However, the DIF plants are exposed to during the period of maximum elongation

will have a major influence on final height. Research during the past year

quantified the growth rate of the poinsettia after pinch but prior to flower

initiation and quantitatively defined plant characteristics at the time

of flower initiation. A temperature based degree day model was developed

from this research which provides the information necessary for a grower

to reliability produce a poinsettia with desired plant characteristics

from crop to crop and year to year. Mr. Robert Berghage completed his Ph.D.

in this program. In addition to the leaf unfolding model, he developed

a model which predicts stem elongation under a wide range of environmental

condition.

Research during the coming year will center on further validation of

these models both in our research facilities and in commercial greenhouses.

A major goal will be to further define the optimal plant characteristics

at the time of flower initiation. This research will be conducted both

in our research facilities and in commercial greenhouses.

3) Modeling the growth and development of the Easter lily. The Easter

lily is one of the more difficult crops to grow due to the variability

in plant material within a year, between years, the variation in date of

Easter and the short marketing period for the crop. Our research program

has emphasized development of quantitative relationship between the growth

of the lily and temperature. The three areas emphasized are 1) the relationship

between DIF and stem elongation, 2) the relationship between temperature

and rate of leaf unfolding, and 3) the relationship between temperature

during the vernalization phase and flower initiation.

Research during the past year further quantified the response of the

Easter lily to temperature. Experiments were conducted to quantify 1) the

effectiveness of temperatures from -2.50C to 22.5′C and photoperiod in

promoting flower induction and 2) growth rates of plants developing from

different sized bulbs under common environmental conditions.

Research during the coming year will center on development of computerized

grower management tools. These programs/tools will assist growers by providing

suggested day and night temperatures to grow the lily crop based on current

developmental characteristics of the plant and desired final characteristics

of the plant.

4) Development of models of growth on other plants. Most of our research

has centered on three major crops, the poinsettia, the chrysanthemum and

the lily. Research during the past year expanded our modeling efforts to

other crops. Experiments were conducted on 1) African violet, 2) New Guinea

impatient, 3) Christmas cactus, 4) gerbera, 5) Boston fern, and 6) fuchsia.

Research during the coming year will center on African violet, Christmas

cactus, and Heimalis begonia.

5) Development of grower management tools. We believe it is very important

to develop management tools from the information generated in the research

we conduct. This is an ongoing process. Management tools developed or in

the process of development include:

a) Graphical tracking the height and rate of development of the Easter

lily. This management system has been published in the trade press and

is currently gaining wide acceptance with lily forcers. b) Graphical tracking

the height of chrysanthemum and poinsettia. This management system has

been published in the trade press and is currently gaining acceptance by

poinsettia growers.

c) A form of an “expert system” for use by lily forcers. This management

tool computerizes the graphical tracking information described above. Development

of this tool continues and will be tested in commercial greenhouses during

the 1989-90 lily forcing season, d) Graphical track poinsettia rate of

development prior to flower initiation by the of a temperature degree day

model. This model will be commercially tested on the 1989 poinsettia crop.

SUMMARY

Two main projects each with five specific project areas have been outlined.

The projects under the direction of John Biernbaum are to define the changes

in irrigation and fertilization practices that must be adopted if our industry

is to survive increasing environmental regulations and decreasing water

resources and will be in one of the following five areas: 1) Irrigation

and Fertilization Practices, 2) Plant Pathogens in Recirculated Solutions,

3) Root Media Water and Nutrient Efficiency, 4) Root Media pH Management,

and 5) Sources of Water and Water Quality, The projects under the direction

of Royal Heins involve research to increase our understanding of how temperature

and light can be used to regulate plant growth and be in one of these five

areas: 1) Control of stem elongation by day and night temperature, 2) Modeling

the growth and development of poinsettia, 3) Modeling the growth and development

of the Easter lilyg 4) Development of models of growth on other plants,

5) Development of grower management tools.

BUDGET

Our primary request is for moneys to support graduate student assistantships

and support their research. We believe in a strong graduate student program

as this trains our teachers And researchers of the future.

1989

REQUESTED $66,000 FUNDED $44,50020`

1990

4 Graduate assistantships @ $12,500 $50,000

Research support @ $5,000 / student /year $20,000

TOTAL REQUEST $70,000

1991 - 1993

The request remains the same but increased by the rate of inflation

to maintain the program at the same level in real terms. This budget assumes

5% but actual requests in future years may vary as assistantship and inflation

costs vary.

1991 - $73,500 1992 - $77,175 1993 - $81,000

APPENDIX

QUALIFICATIONS OF THE APPLICANTS

RECENT PUBLICATIONS AND PRESENTATIONS

R o y a 1 0. H e i n s

Personal

Date of

Birth: July 14, 1953

Marital

Status: Married, two children

Academic

Degrees

B.S. -

1975 - Colorado State University

Ph.D.

- 1978 - University of Minnesota

Professional

Experience

1988 -

Present - Professor, Department of Horticulture, Michigan State University

1983 -

1988 - Associate Professor, Department of Horticulture,

Michigan State

University

1978 -

1983 - Assistant Professor, Department of Horticulture,

Michigan State

University

1975

1978 Graduate Assistant, Department

of Horticulture and Landscape

Architecture, University of Minnesota

1971

1975 Undergraduate Research Assistant,

Plant Environmental Research

Center, Colorado State University

Academic

Responsibilities

Research

- 70%

Teaching

- 30%

Honors

and Awards

Phi Kappa

Phi, Phi Alpha Xi, Gamma Sigma Delta, Sigma Xi, The Kenneth Post Award,

ASHS,

1980

Professional

Organizations

American

Society for Horticultural Sciences, International Society of

Horticultural

Sciences, NCR 101 Controlled Environment Working Group

Current

Research Projects

1. Modeling

chrysanthemum, poinsettia, and Easter lily growth responses to

temperature and irradiance.

2. Determining

the dynamics of stem elongation in response to temperature.

3, Use

of day and night temperature to control stem elongation in greenhouse

crops.

J o h n A. B i e r n b a u m

RANK: Assistant

Professor

WORK ADDRESS:

HOME ADDRESS:

Horticulture

Department

2104 Robinson

A234 Plant

and Soil Science Bldg.

Lansing, MI 48910

Michigan

State University

East Lansing,

MI 48824

(517)394-2718

(517)353-7728

DATE OF

BIRTH: 4-3-57

MARITAL

STATUS: Married, two children

CURRENT

POSITION: Assistant Professor

Teaching

Research

DATE OF

APPOINTMENT: 8-1-85

ACADEMIC

DEGREES:

Ph.D.

Horticultural Science Michigan

State University

5-85

M.S.

Horticultural Science The

Pennsylvania State University

8-81

B.S.

Horticultural Science North

Carolina State University

6-79

PROFESSIONAL

EXPERIENCE:

Date

(Year) % of Time

Employer

Position Title

From

To Employed

1975

1979 25

NCSU Horticulture Department

Research Assistant

1979

1981 50

PSU Horticulture Department Grad

Research Asst.

1981

1984 50

MSU Horticulture Department

Grad Research Asst.

1985

Present 100

MSU Horticulture Department

Asst. Professor

PROFESSIONAL

ORGANIZATIONAL MEMBERSHIPS:

American

Society for Hort Science

6;4712f1979

Sigma

Xi

1984

Pi Alpha

Xi

1978

Gamma

Sigma Delta

1979

ROYAL D, HEINS

GROWER ARTICLES IN

THE TRADE PRESS AND EXTENSION BULLETINS

3

Erwin, John, Royal

Heins, Robert Berghage, Meriam Karlsson, William Carlson,

and John Biernbaum.

1988. Why grow plants with warmer nights than days?

GrowerTalks 51(12)48-56.

Biernbaum, John A.,

William H. Carlson and Royal D. Heins. 1988.

Fertilization strategies

for bedding plants, American Vegetable Grower

36 ( 2) :58-64.

Kaczperski, Mark P.,

William H. Carlson, Royal D, Heins and John Biernbaum.

1988. Petunias designed

by cool days/warm nights. GrowerTalks 52(l):37-39.

Biernbaum, John A.,

William H. Carlson and Royal D. Heins. 1988. A Common

Sense Approach to

Prevent Ground Water Contamination. GrowerTalks 52(3)146-

153,

Heins, R,,, J. Erwin,

R. Berghage, M. Karlsson, J. Biernbaum, and W. Carlson.

1988. Use temperature

to control plant height, Greenhouse Grower 6(9):32-

37*

Biernbaum, John A.,

Renee George, Royal D. Heins and William H. Carlson,

1988, Subirrigation

with recirculated solutions. A better way to manage

water? GrowerTalks

52(4):79-94.

Berghage, R., R. Heins,

J. Erwin, W. Carlson, and J. Biernbaum. 1988.

Increase bract size

with temperature and light. Greenhouse Grower 6(10):

40, 43-44a

Berghage, R., R. Heins,

W, Carlson, J. Erwin, M. Karlsson and J. Biernbaum.

1988. Tips on pinching

poinsettias. Greenhouse Grower 6(8):14-15.

Biernbaum, John, William

Carlson, Candice Shoemaker, and Royal Heins. 1988.

Low pH causes iron

and manganese toxicity, Greenhouse Grower March:92-93,

96-97,

Heiden, Ralph W.,

Monica J. Schmidt, William H. Carlson, Royal D. Heins, and

John A. Biernbaum.

1988, Production of ground covers as bedding plants.

Cooperative Extension

Service, MSU, Extension Bulletin E-2127, Sept, (New).

Erwin, John and Royal

Heins. 1988. New concepts on how day and night

temperatures affect

plant growth, PPGA News, Vol. XIX, No. 11.

Erwin, John E., Royal

D. Heins, Robert Berghage, Brian J. Kovanda, William

H. Carlson and John

Biernbaum. 1989. Cool mornings can control plant height.

GrowerTalks 52(9):73-74.

Biernbaum, John A.,

William H. Carlson and Royal D. Heins.

1989. The

groundwater challenge.

Michigan Florist Jan/Feb issue, pg.18.

Heiden, Ralph W., William

H. Carlson, Royal D. Heins, John A. Biernbaum,

4

and Lowell Ewart,

1989. Producing Vegetable Transplants as Bedding Plants.

Cooperative Extension

Service, MSU, Extension Bulletin E-21481 Feb. 1989 (new).

Hausbeck, Mary, Christine

Stephens and Royal Heins, 1989. Choose resistant

cultivars. Greenhouse

Grower 7(6).

Erwin, John, Royal

Heins, Robert Berghage and William Carlson. 1989. How

can temperatures be

used to control plant stem elongation? Minnesota State

Florists Bulletin,

38(3) June.

Biernbaum, John A.,

William H. Carlson and Royal 0. Heins, 1989. Managing

the greenhouse, protecting

the environment. SAF July.

SCIENTIFIC PUBLICATIONS

Karlsson, M.G., R,D.

Heins, and J,E. Erwin. 1988. Quantifying temperature

controlled leaf unfolding

rates in Lilium longiflorum Thunb. ‘Nellie White’.

J. Amer. Soc. Hort.

Sci. 113(1):7o-T4@;36;36q,

Karlsson, M.G., M.P.

Pritts, and R.D. Heins. 1988. Path analysis of growth

and development in

chrysanthemum. HortScience 23(2):372-375.

Hausbeck, Mary, Christine

Stephens, and Royal Heins. 1988. Control of disease

caused by Pythiurn

ultimurrt in seect pr-cimgated geraniums rpraved nr nnf

.r. J .. @. .@ .

sprayed witE silver

thiosulphate. Plant Disease 72:764-768.

Holcomb, E. Jay, J.A.

Flore and R.D. Heins, 1988, Photosynthetic response

curves for chrysanthemum

grown at different PPF levels, HortScience

23(l):206-208.

Erwin, J.E., R.D. Heins,

and M.G. Karlsson. 1989. Thermomorphogenesis in

Lilium longiflorum.

Am. J. Bot. 76:47-52.

Karlsson, Meriam G.,

Royal D. Heins, John E. Erwin, Robert 0. Berghage,

William H. Carlson,

and John A, Biernbaum. 1989. Temperature and photo-

synthetic photon flux

influence chrysanthemum shoot development and flower

initiation under short-day

conditions. J. Amer. Soc. Hort. Sci. 114(l):

158-163,

Karlsson, M,G,, and

R,D, Heins, 1989, Rate of development during four phases

of chrysanthemum growth

as affected by preceding and prevailing temperatures.

J. Amer. Soc. Hort.

Sci. 114(3):XXX-XXX.

Karlsson, M.G., R.D.

Heins, W.H. Carlson, and J.A. Biernbaum. 1989.

Irradiance and temperature

effects on time of development and flower size in

Cchrysanthemum.

Scientia Hortic. (a-ccepted4o”ub44-c-a-tion), 17′ 2@@?- 2-4r2

Berghage, Robert D.,

Royal D, Heins, Meriam Karlsson, John Erwin, and William

Carlson. 1989. Pinching

technique influences lateral shoot development in

poinsettia. J. Amer.

Soc. Hort. Sci. (accepted for publication).

Erwin, J.E., R.D. Heins,

M.G, Karlsson, W.H. Carlson, and J.A. Biernbaum,

5

1989, The influence

of day and night temperature on Easter lily development

from the visible bud

stage until flower. HortScience (in review).

Hausbeck, Mark K.,

Royal 0. Heins, and Christine T. Stephens. 1989. The effect

of fungicide drenching

schedules on size and flowering of seed-propagated

geraniums, HortScience

(In review).

ABSTRACTS OF PRESENTATIONS

AT SCIENTIFIC MEETINGS

Berghage, R.D. and

R.D. Heins. 1988. Plant developmental stage influences

temperature-induced

stem elongation, HortScience 23(3).

Erwin, J.E. and R.D.

Heins. 1988. Effect of diurnal temperature fluctuations

on stem elongation

circadian rhythms. HortScience 23(3).

Erwin, J.E. and R.D.

Heins, 1988, Thermomorphogenic stem elongation

responses in plants.

HortScience 23(3),

Karlsson, M.G., ;5288;392;148sR.D.

Heins, J,E, Erwin and R.D. Berghage. 1988. Biomass

allocation patterns

in chrysanthemum. HortScience 23(3).

Lange, Nathan E. and

R.D. Heins. 1988. Interaction of photoperiod and

temperature in promoting

flowering of Lilium longiflorum. HortScience

23(3),

Berghage, R.D. and

R.D. Heins. 1989. Prediction and control of poinsettia

development from pinching

to flower initiation. HortScience

Erwin, J.E. and R.D.

Heins. 1989. Effects of temperature on Sclumbergera

truncata flower initiation.

HortScience

Erwin, John E. and

Royal D, Heins, 1989. Effects of temperature and

photoperiod on Fuchsia

x hybrida. HortScience

Lange, Nathan E. and

Royal D. Heins. 1989,.Relationship between temperature

and flower induction

in Lilium longiflorum. HortScience

Robinson, Jack and

Royal D. Heins. 1989. Modeling leaf unfolding and

flower development

in Saintpaulia ionantha cv. Utah, HortScience

ORAL PRESENTATIONS

TO INDUSTRY GROUPS

6

August 16, 1988

Floriculture & Wood Orna.

A New P

y

erspective on Tempera-

mental Days at MSU

ture Control of Height & Rate

East Lansing, MI

of Development in Bedding &

Pot Plants

September 13,

1988 Westbrook Greenhouse

Modeling Growth of Green-

Ontario

house Crops with Temperature

and Light

October 21,

1988 Nebraska/Iowa Greenhouse

Lilies and Bulb Crops

Meeting, Omaha, NE

October 22,

1988 Nebraska/Iowa Greenhouse

All About Poinsettias

Meeting, Omaha, NE

July 25, 1989

Fifth Annual Floriculture and Principles

of Poinsettia

Woody Ornamental Days at MSU Production

East Lansing, MI

JOHN A. BIERNBAUM

GROWER ARTICLES IN THE TRADE

PRESS AND EXTENSION BULLETINS

Heiden. Ralnh W__ Mnnira

J 4@ rh mi eff Willimm W

D @.. .’1 n

‘A”‘v”‘ ‘Oul 1″119 rwyal D, nelflb, dnU John

;364;108saum. iiH-’.”P”‘d”t’@ o

0

A. Biernb

ro uc i n

co ers as bedding plants. Cooperative

Extension Service, MSU,

Extension Bulletin E-2127, Sept. (New).

Biernbaum, J.A., W.H. Carlson

and R,D, Heins, 1988. A common sense approach to

prevent ground water contamination.

GrowerTalks 52(3):146-153.

Biernbaum, John A., Renee

George, Royal 0, Heins and William H. Carlson,

1988

Subirrigation with recirculated

solutions, A better

way to manage water;

GrowerTalks 52(4):79-94.

Biernbaum, J.

1988. Alternative irrigation methods.

Interior Landscape

Industry 5(4):40-49.

Heins, R., J. Erwin, R.

Berghage, M. Karlsson, J. Biernbaum and W, Carlson,

1988. Use temperature to

control plant height. Greenhouse Grower 6(9):32-37.

Kaczperski, Mark P., William

H, Carlson, Royal D, Heins and John Biernbaum.

1988, Petunias designed

by cool days/warm nights, Growerl’alks 52(l):37-39.

Erwin,, John E,, Royal D.

Heins, Robert Berghage, Brian J, Kovanda, William H.

Carlson and John Biernbaum.

1989. Cool mornings can control plant height,

GrowerTalks 52(9).

Biernbaum,

John A,, William H, Carlson

and Royal D. Heins. 1989.

The

groundwater challenge.

Michigan Florist Jan/Feb 1989,

Biernbaum, J,A, and

C. Peterson. 1989, The groundwater challenge. Michigan

Association of Nurserymen

Newsletter. Feb. 1989.

Biernbaum, J.A. and

W. Fonteno. 1989. Minimize Groundwater contamination.

Greenhouse Grower

7(2):90-95.

Biernbaum, J.A., M.

Yelanich, R. Heins and W. Carlson, 1989. Irrigation and

fertilization go hand

and hand, Grower Talks (September).

Biernbaum, J.A., R,

Heins and W, Carlson. 1989. Keeping water and fertilizer

in the root zone.

Grower Talks (September).

Biernbaum, J.A.’ R.

Heins and W. Carlson, 1989, Is the water warm? Grower Talks

(September).

George, R., J. 44sBiernbaum

and R, Heins. 1989. Pathogen control with recirculated

water. Grower Talks

(September).

Biernbaum, J.A.’ W.H.

Carlson and R.D. Heins. 1989. Managing the greenhouse,

Protecting the environment.

SAF Magazine 6(4):21-24.

SCIENTIFIC PUBLICATIONS

Biernbaum, J.A., R.L.

Houtz and S.K. Ries. 1988. Field studies with crops

treated with colloidally

dispersed triacontanol, Journal of Amer. Soc. Hort.

Sci. 113(5):679-684.

Karlsson, Meriam G,,

Royal 0, Heins, John E. Erwin, Robert D. Berghage, William

H, Carlson and John

A. Biernbaum. 1989. Temperature and photosynthetic photon

flux influence chrysanthemum

shoot development and flower initiation under short-

day conditions. J.

Amer. Soc. Hort. Sci. 114(l):158-163.

Karlsson, M.G., R.D.

Heins, W.H. Carlson and J.A. Biernbaum. 1989.

sIrradiance

and temperature effects

on time of development and flower size in chrysanthemum.

Scientia Hortic. (accepted

for publication),

George, R. and J.A.

Biernbaum. 1989. Potential for transfer of Pythium ultimum

in production of seedling

geraniums with subirrigation and recirculated solutions.

ISHS Symposium on

Bedding and Pot Plant Culture. April. Acta Horticulturae

(to be published).

Yelanich, M, and J.A.

Biernbaum. 1989. Effect of fertilizer concentration and

method of application

on media nutrient content, nitrogen runoff and growth of

Euphorbia pulcherima

V-14 Glory, ISHS Symposium on Bedding and Pot Plant Culture.

April, Act5

(to be published),

Biernbaum, J.A. 1988, Evaluation

of subirrigation systems for interior plants,

HortScience 23(3) :752*

George, R. and J.A. Biernbaum.

1988. Water use and growth of poinsettia and

Easter lily with top watering

versus subirrigation with recirculated solutions.

HortScience 23(3):779.

Yelanich, M.V. and John

A. Biernbaum. 1988. Fertilization and irrigation of

bedding plants with subirrigation

and recirculated water. HortScience 23(3):782.

George, R. and J,A. Biernbaum.

1989, Potential for transfer of Pvthium ultimum

in production of seedling

geraniums with subirrigation and recirculated solutions,

ISHS Symposium on Bedding

and_Pot Plant Culture, April 1989,

Yelanich, M, and J.A. Biernbaum.

1989. Effect of fertilizer concentration and

method of application on

media nutrient content, nitrogen runoff and growth

of Euphorbia pulcherima

V-14 Glory, ISHS Symposium on Bedding and Pot Plant

Culture. April 1989,

ORAL PRESENTATIONS TO INDUSTRY

GROUPS

8/17/88 Protecting

the Environment MSU Floriculture and Woody

75

(1/2 day seminar for the Ornamental

Days

landscape and greenhouse

industries)

10/7/88 Groundwater

Protection and BPI Annual Conference

200+

Subirrigation

San Antonio, Texas

10/26/88 Groundwater

Protection and Detroit Flower Growers

100+

Subirrigation

Detroit, MI

11/22/88 Groundwater.Protection

and Western Michigan Greenhouse

50+

Subirrigation

Growers Conference

1/8/89

Groundwater Protection and Grower 912;524;176sExpo

95

Subirrigation

Pheasant Run, ILL

2/1/89

Groundwater Protection and Detroit Metro

Flower Growers 40+

Subirrigation

Workshop

Detroit, MI

6/28/89 Root

Zone Systems for the 1989 Seeley Conference

60+

21st Century

Cornell University

7/10/89 Ebb

and Flow Irrigation Ohio

State Short Course

300+

Systems

Columbus, Ohio

7/25/89 Water

Management for Green- MSU Floriculture and Woody

30

house Production

Ornamental Days

7/26/89 Pesticide

Certification for MSU Floriculture and Woody

10

the Interior Landscape

Ornamental Days

Industry