Transcript - JEAI

JEAI
ECO-RUBBER
Impact of legumes intercropping
on soil functioning and rubber
physiology
Set up of an experimental layout in
Buriram
Context
• Our previous work (Marin et al., 2013, Arunee
and Milena 2014) showed that intercropping
has an important effect of soil bio-functioning.
• Legumes seems to have an important impact
on soil nutrients, tree physiology (N transfer
see work of Clermont dauphin), water soil
status, weed prevention etc..
Objective
• Compare the effect of legume’s intercropping
to cassava intercropping on parameters link
to soil and plant functioning
• Select within 3 legumes the most efficient one
in terms of N transfer, soil nutrients, soil
biodiversity and activities, soil moisture, tree
growth etc..
Layout characteristics
•Tree age: 2 years old
•Previous crop : Eucalyptus
•Crop clone: RITT251)
•Plot size: 25 rai (4,2ha)
Tree girth size
Made by Tum
in May 2014
Measure of the girth
Choice of legumes !
Legumes
Mucuna bracteata
Advantage
Inconvenient
Easy to growth
Propagation through cuttings
(T° and humidity too high in
Thailand for seeding)
deep-rooted fast growing
moderate drought
resistance at the beginning
after growing
shade tolerance
grows fast and covers the
field very quickly
suppresses all weeds
Nitrogen fixing capacity
was found to be high and
make it available to the
main crop
impedance to beetle
breeding
reducing loss of nutrients
Choice of legumes !
Legumes
Advantage
Calopogonium caeruleum Weed control
Increase organic matter
nutrient cycling efficiency
inhibited erosion
reduce fire (in the south)
Decrease the day of tapping
drought tolerance
shed tolerance
reduce management and
labor
Pueraria phaseloides
Weed control
Increase organic matter
Inconvenient
expensive
Cause of fire (shed leaves in
the northeast)
Cause of fire (shed leaves in
the northeast)
No drought and shed
tolerance
Nutrient cycling efficiency High fertilizer using
Inhibited erosion
Layout in 4 blocks
Cassava
MUCUNA
CALOPOGONIUM
PRERARIA
Control
Control
Cassava
CALOPOGONIUM
MUCUNA
PRERARIA
PRERARIA
CALOPOGONIUM
CALOPOGONIUM
MUCUNA
Cassava
MUCUNA
Control
Control
PRERARIA
Cassava
Block design
BLOC1
BLOC2
BLOC3
BLOC4
Each plots = 6 lines X 12 tree
Soil sampling 0-5/5-10/ 10-20)
Studied Area
Measurements
(Christian H, Henri R, Claude H. Nok, Supat) Student ?
• Meteorological records
– station Davies or Campbell (here in Bangkok) (Norbert for installation ?)
• Soil physical parameters (Inter- row + row)
– Soil resistivity : Henri in September with ETR
– Soil water content
• sensor Sentec in each row-inter row (6 PVC tubes/ Plot x 24 plots = 144
tubes
• Mobile sensors (trim pro) : more specific for surface measurements
• Soil solution (soil trap) (CH)
– Hydric potential
• Tensiometers or psychometrics sensors (Claude H & F.Do)
• Do we have some available from BNT ? How many we need for the exp ?
– Others physical parameters :
• bulk density, texture ( C.H and LDD Region 5 or LDD Bangkok ? (Nok.)
– Chemistry (soil and water solution)
• pH, Nm , P, K, OM, C ,N, (NIRS ? NoK.
Ecophysiological tree measurements
(Supat, F. Do, P. Thaler, F. Gay) Student ?
• NPP : Tree girth and length
– KU Equipment for tree length available ? (FG)
– Periodicity (each 2 months ?) (FG)
• Litter fall (litter trap)
– Is it necessary ? What model (for FG and PT)
• LAI (fish-eye)
– Could we use LMI-KU equipment ? Who can be involved in the analysis ? (FG)
• Foliar potential
– See if Wattman sensors exist in KKU, are they available for this exp ? (Supat and Fred Do)
– Who will be in charge (Supat Student ?) (Supat and FD)
• Sap Flow
– Pb damage the tree, is it necessary now ? (Supat, FD)
• Mineral content (Supat, F. Do, P.T)
– Mg, Ca+, what else ?
– Done by Spad ?
– Could we use it periodically ?
Measurements at the intercrop
(Kiriya and Didier Lesueur) Alain P ? Master Student KKU Wasithi
• Plant Biomass
– Shoot Biomass, Root, Nodules What periodicity ?
– LAI ??? (not sure to understand ?)
• Microbial (need to be more detailled Kiriya)
• Isolation of N fixing bacteria, PSP (How ? )
• PSP
• Roots ? (Alain P ? )
N transfert (legumes Tree)
(Cathy CD, Kiriya Master student Wasithi ? )
• N2 fixation by the legumes
–
15N
natural abundance method using samples of
leaves, stems and roots collected each year on the
interrank crops
– The non legumes interrank crops will be used as
non fixing reference plants for the calculations of
Ndfa
– Biomass of each plant compartment at the period
of these samplings will be needed for calculations
of N2 stocks
Soil biological diversity
(Prakaijan, Chutinan, Alain B., Master student KKU Treenuch promnok (som),
Phd Student LDD Kee
• Microbial activity and Diversity (PhD Kee+ AlainB )
• Bacterial and fungal biomass
• Catabolic profiles
• Genetic structure
• Nematodes diversity (Som + Prakaijan)
– Free living nematodes
– Entomophatogenous
• Soil Fauna Diversity (Som + Chutinan + master ?)
Others ???
Kam khup krap
SEE YOU SOON
Cassava intercropping