Zulle FYP Presentation

8/13/2019 Zulle FYP Presentation

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Effects of light and drought treatment on two species ofDryobalanops

09B3047

Muhd Zulhilmi bin Hj Ali

14thMay 2013


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Main aim: Investigate the effects of different

light and drought treatments on seedling

growth and survival ofDryobalanops beccariiandDryobalanops rappa.


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150 seedlings of eachDryobalanopsspecies from forestrydepartment

Left for acclimatization for one month in a plant house withshades of two layered nettings.

Watered daily, exposed to ambient temperature andhumidity but without any fertilizer

80 of each species is then chosen, 50 for light and 30 fordrought

Measurements were taken monthly from Sept 2012 until

Feb 2013. Monthly measurements taken were seedling height,

diameter, no. of leaves and survival. Other measurementsinclude monthly rainfall, relative humidity, air temperature

and PAR.


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Two factorial experiment

10 seedlings per replicates per treatment arranged in blocks

of 2 by 5 with 30 cm spacing between the pots

5 different treatments of light:-

A. Full light treatment

B. One layer of shade

C. Two layers of shade

D. Three layers of shade

E. Three layers of shade top, 2 layers side 3 different treatments of drought:-

1. High frequency watering

2. Medium frequency watering (once a week)

3. Low frequency watering (once every two weeks)


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XD. beccarii

D. rappa

Red boxLight treatmentBlue boxDrought treatment

AFull light BOne layer shade C2 layers shade

D3 layers shade E3 layers shade top and 2 layers side


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During initial harvest (Sept 2012), about 15seedlings of each species were taken. Non-destructive measurements taken and these

seedlings were separated into roots, stems andleaf fractions. Fresh soil from seedling pots were used to

measure soil PH while remaining soil was airdried and used to measure nutrients.

Final harvest (Feb 2013) procedure similar exceptthat all the seedlings in the study were harvestedinstead.


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RGR = (loge W2loge W1) / (t2t1) (1)

where W2and W1is final and initial, t2t1 is 5

months Statistical analysisR 2.15.2 (R Development

Core Team, 2012)

All RGR values were log10

if assumptions

violated

Two-way ANOVA


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D. rappa shows significant

productivity in height and diameter

compared toD. beccarii

D. beccarii shows a significant

difference in RGRleaves

Treatment D ofD. rappashows

significant difference between other

treatments especially on RGRdiameter

and RGRheight Treatment A of RGRleavesofD.

beccariishows significant

difference when compared to other

treatments and alsoD. rappa

Treatment

RGR

Diameter,mm

mm

1

month1

0.00

0.01

0.02

0.03

0.04

A B C D E

D.Beccarii

A B C D E

D.Rappa

Treatment

RGR

Height,cm

cm

1

month

1

-0.04

-0.02

0.00

0.02

0.04

0.06

A B C D E

D.Beccarii

A B C D E

D.Rappa

Treatment

Numberofleavesmonth1

0.00

0.05

0.10

0.15

0.20

A B C D E

D.Beccarii

A B C D E

D.Rappa

Treatment

RGR

Biomass,g

g1

month1

0.0

0.1

0.2

0.3

0.4

A B C D E

D.Beccarii

A B C D E

D.Rappa


10/20

Significant differences betweenspecies exist in all the

parameters except for RGRheight D. rappa shows a significant

growth in RGRdiameteras

opposed toD. beccariialthough low water treatment of

D. rappa shows similar rangeto that ofD. beccarii

RGRleaves andRGRbiomassis

marginally significant Mid watering treatment of

RGRbiomass ofD. beccariishows significantly lower valuethan high and low watering

treatment but such patterns donot exist inD. rappa

Treatment

RGR

Diameter,mm

mm

1

month1

0.000

0.005

0.010

0.015

0.020

0.025

Hi gh Medi um Low

D.Beccarii

Hi gh Medi um Low

D.Rappa

Treatment

RGR

Height,cm

cm

1

month1

0.00

0.01

0.02

0.03

High Medium Low

D.Beccarii

Hi gh Medi um Low

D.Rappa

Treatment

Numberofleavesmonth1

0.00

0.05

0.10

0.15

Hi gh Medi um Low

D.Beccarii

Hi gh Medi um Low

D.Rappa

Treatment

RGR

biomass,g

g1

month

1

0.0

0.1

0.2

0.3

Hi gh Medi um Low

D.Beccarii

Hi gh Medi um Low

D.Rappa


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Parameters Treatment SpeciesTreatment x Species

interactionRGRdiameter < 0.001*** < 0.001*** < 0.01**

Light

treatmentsRGR

height 0.041* 0.107 0.318

RGRleaves 0.062 < 0.001*** < 0.01**RGRbiomass 0.327 0.440 0.315RGRdiameter 0.2545 < 0.01** 0.175

Drought

treatmentsRGRheight 0.184 0.649 0.203

RGRleaves 0.608 0.048* 0.697RGRbiomass 0.6861 0.045* 0.037*

Most significant difference

found in RGRdiameter

between treatments, species

and treatment x species RGRleavesbetween two

species in light shows a

very significant difference

in light treatment too

Drought treatments doesntshow much difference

except for RGRdiameter

between species


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0

10

20

30

40

50

60

70

80

90

100

A B C D E

D. Beccarii

D. Rappa

In light,D. rappashows highertolerance with treatment C showinghighest % survival

D. beccarii shows lower survivalthroughout when compared toD.

rappa In drought,D. rappaagain shows

high tolerance level (>80% in alltreatments)

D. beccariidoesnt seem to show a

high tolerance level to droughtwhere mortality rate is


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D. rappaseems to possess the ability to invest growth in stem diameter

despite being short when compared toD. beccarii.

D. rappa also showed greater productivity in stem height growth but

prioritizes more energy into increasing girth than vertical growth

D. beccariiinvests in increasing the number of leaves. The leaves ofD.beccariiare smaller but abundant, branches produced are also more in

numbers and much longer

Treatment A ofD. beccariishows a significance in RGRleaves due to

similarity toD. aromaticaa shade tolerant species (Saw, 2003). Being

shade tolerant meaning that living in full light actually hinders theirgrowth, reduces overall leaf number, decreases photosynthetic activity

which leads to slow growth

D. rappaunder treatment E shows a poor performance as treatment E

closely resembles forest canopy. Between treatment D and E,D. rappa

shows significant difference in RGRdiameter

and RGRheight


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Treatment C seems to have the most suitable environment for

both species to grow althoughD. rappahas a higher

survivability

D. rappa overall shows a strong resiliency towards the

varying treatments of light be it under direct sunlight orsimulated canopy

Throughout the study,D. rappaalso shows bigger leaves

which belongs to characteristics of light-demanding species

(Brown and Whitmore, 1992) D. beccarii shows similar abilities to that of Shoreaby

investing energy in leaf production instead of height or

diameter. Perhaps,D. beccariimight as well invest in

increasing root mass though this needs to be further studied


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Drought seems to have no effect on RGRheight

However, significant differences between the RGR

diameter, leaves and biomass implies that under

drought conditions both species are able to allocateenergy to grow vertically

Increasing height is viable as increase in girth would

mean that it has to catch up by increasing the ability

to store water and biomass Most similar studies shows relation between drought

and allocation of dry mass to roots however this was

out of scope of the current study


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D. rappa has a high rate of survivability that doesnt fall

below 80% even at low watering treatment. This makes sense

asD. rappa is a drought-tolerant species (Chua, 2003)

D. beccariishows poor performance towards water stress byobserving the low % survivals. Its obvious since they are

sensitive to water deficit as stated by Guhardja (2000)

Anomality inD. beccariiwhere in this study the medium

watering treatment shows the lowest survival when its

supposed to be low watering treatment. Throughout the

study, rain was not completely excluded from study sites

hence low watering treatment might just receive some extra

rainfall.


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Time frame is too short for a tree study.

Dipterocarpaceae family are known to be slow

growing trees (Ashton, 2002) Study site is an open, disturbed area.

Natural phenomena such as strong winds

during final months of 2012 dislocated the

seedlings a few times. This hinders their

growth and may induce stress which results in

poor growth


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D. rappaoverall has shown strong tolerancetowards the two treatments especially drought

D. beccarii is the less resilient, but has shownsuccess in investing towards the production ofleaves

Various growth strategies exist even in these

two close species Long-term study where time frame of 5

months is not enough to give out a moresignificant finding.


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Id like to give my greatest gratitude to my

supervisor Dr. Rahayu, and co-supervisor Dr.

Faizah for their endless support Huge thanks for the technicians Shahidah,

Teng Wei and Redzuan.

Lastly, to the people who helped me

throughout with the laborworks.

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