1
Alabama A&M University REU at Nanjing
Forestry University, China
A Cultural/Research Experience
By: Nara McCray
大学生科研实践
• Rising senior at Alabama
A&M University
• From Anchorage, AK
• No previous research
experience
• Chinese mentor Dr. Ben
Fan
• Assisted by his graduate
student Summer (Xia
Yong-xian)
2
• The main objective of this
research was to determine
if x, N12 & N6 are Plant
Growth Promoting
Rhizobacteria (PGPR)
• Extensive resarch is being
done in this area to
identify potential
biofertilizers
3
• PGPR stands for Plant
Growth Promoting
Rhizobacteria
• Rhizobacteria are
typically symbiotic-rootcolonizing bacteria
Rhizosphere
4
• Provide ammonia (nitrogen
fixation) as well as nutrients
to the plant
• Displace detrimental
microorganisms and
produce growth
phytohormones
5
N-12/N-6
• N-6 and N-12 are unidentified
bacterial strains
• Chosen by Dr. Fan because of
superior performance in
isolation procedures:
• Produced exopolysaccarides
• Solubilized silicates &
potassium
• Phytohormone production
• Nitrogen fixation (free-living,
not legume)
• Tested as PGPR and
hypothesized to be Bacillus
mucilaginosus - a soil
bacterium widely used in
China as a biofertilizer
6
• X is a spontaneous/
accidental discovery during
Dr. Fan’s bacterial isolation
procedure
• Interest in biocontrol
• Hypothesis: X, N6, and N12
are PGPR
7
研究方法
1. Germinating corn seeds were inoculated with three
separate strains of bacteria for comparison with control
2. Seeds then planted in sterile soil
3. Plants then measured and compared to determine
bacterial strain influence
8
Similar to protocol used in A. Gholami’s “The Effect of PGPR on Germination,
Seedling Growth and Yield of Maize”
• 400 seeds germinated
• The best 144 seeds
inoculated by dipping
root into culture masses
• The seeds were then
planted in sterilized soil
• Three seeds per pot
9
Latin Square
X
CK
N6
CK N6 N12
N6 N12 X
N12 X
CK
X
CK
CK
N6
N12 N12
X
CK
N6
N6
CK
X
X
CK
N6
N12 X
CK
N6 N12 X
CK N6 N12
N6 N12 N12 X
N12 X
N6 N12
CK
X
N6
CK
The method in which we organized the pots
10
This organization was done to reduce any bias that may have occurred due to
sun/shadow exposure on pots containing one particular strain.
(CK are control corn plants)
RESULTS 结果
The maize seeds
were planted June
10th
11
After a growth
period of a month
the fresh/dry
weight and
root/shoot length
for the vigor index
was obtained
PRELIMINARY DATA 当前数据
Data obtained Wednesday June 27th 2012
12
FINAL DATA
13
Data obtained July 5th 2012
Data obtained July 5th 2012
14
WEIGHT
DATA
Discussion

The experiment did
not result as
expected because
◦ The strains are not
PGPR
◦ Maize is not a suitable
model
◦ The experiment was
not performed well
15
• This experiment is an
extension of Dr. Ben
Fan’s greater project
• This experiment will be
modified and repeated
with dicotyledon
• X could possibly be
further experimented
with for antibiotic
medicine potential
16
Having never been out of
the U.S. before. I was very
anxious to experience life
outside our borders
Upon arrival I had many
expectations, some have
been confirmed and many
dismounted.
17
Shanghai
上海
Nanjing
南京
Dr.Sun Yat-sen’s Mausoleum
Nanjing Massacre Memorial
PAPARAZZI!
Etcetera
Sources
•
•
•
•
•
•
•
A Producer of Exopolysaccharides, on Chitin.” Siennabionatec. 19 June 2001. Web.
26 June 2012
Abedon, Stephen. “Supplemental Lecture (98/04/14 update).” mansfield.ohiostate.edu. No Date. Web. 26 June 2012
A.Gholami, S.Shahsavani, S.Nezarat. The Effect of PGPR on Germination, Seedling
Growth and Yield. World Academy of Science, Engineering and Technology 49.
2009.
B. Shaharoona, M. Arshad and Z.A. Zahir. Effect of Plant growth promoting
rhizobacteria containing ACC-deaminase on maize growth under axenic conditions
and on nodulation in mung bean. Institute of Soil and Environmental Sciences,
University of Agriculture, Faisalabad, Pakistan. Letters in Applied Microbiology.
2006.
J.W. Kloepper and M.N. Schroth. Plant Growth –Promoting Rhizobacteria and Plant
Growth Under Gnotbiotic Condition. Department of Plant Pathology, University of
California, Berkeley. The American Phytopathology Society. 21 November 1980
Kuprina, E.E., Nyanikova, G. G., Pestova, O.V., “Immobilization of Bacillus
mucilaginosus,
“Rhizobacteria.” Wikipedia. Wikimedia Foundation, Inc. 8 May 2012. Web. 23 June
2012.
22
Thank You! 谢谢
National Science Foundation
Ben Fan
The End
Summer (Xia Yong-xian)
Alabama A&M Univ. Staff
Nanjing Forestry Univ.
23
Fellow Students