seven decades of leucaena r&d&e in australia: what we have
TRANSCRIPT
Seven decades of leucaena R&D&E in Australia: What we have achieved
1. Brief history of leucaena
2. Leucaena for forage in Australia
3. R&D&E from 1960 onwards
4. Environmental issues
5. Future research priorities
Assoc.Prof. Max Shelton
1. Brief history of leucaena
Origins of Leucaena
Genus found from southern US through Mexico to Central America
Food for several thousand years
Transported to SEA (Philippines) by Spanish colonists (1600s?)
Arrived in Australia late 1800s from PNG
Multipurpose uses
around world (miracle tree)
Furniture Forage
Fuelwood Food
Leucaena for paper pulp in India (~100k ha)
Leucaena wood biomass for power generation
2. Leucaena for forage in Australia
First varieties released in 60s - CSIRO
First commercial plantings early 80s
Large scale plantings began in 90s
Now have >200,000ha supporting >150,000
cattle
Approximately 10-20 tonnes of seed sold
every year = enough for 4000 - 8000 ha/yr
Predict 300-500,000 ha in next 5-10 years
Where grown in Queensland
More than 12 M ha of land
suitable for leucaena
Central Queensland grazier has 6000ha of leucaena
Grazed dryland leucaena in Central Queensland in winter
Central Queensland grazier has 240ha under pivot irrigation
Central Queensland grazier backgrounding Wagyu cattle
How leucaena is established in Queensland
How we establish leucaena
Almost all dryland, unfertilized
Plant double rows, 6-8m centres
Keep weed free until 1-2 m tall, then plant grass
First graze when 2-4 m tall (6-12 months)
Leucaena pasture expected to last 30-40 years
How leucaena is established in Queensland (3 months)
How leucaena is established in Queensland (6 months)
Leucaena being grazed appropriately
The end product
Leucaena in Colombia
Leucaena in Colombia
3. Leucaena R&D&E worldwide (1950-2017)
About 71,000 scientific publications since 1950 (Google Scholar) covering:
• Germplasm collection and analysis, taxonomy.
• Multiple agroforestry uses e.g alley cropping, timber
• Agronomy and plant breeding
• Animal production trials
• Leucaena toxicity and discovery of S. jonesii
• Environment & adoption
0
5000
10000
15000
20000
25000
0 2 4 6 8
Decade
Publications every decade since
1950
!950 – 1960 – 1970 – 1980 – 1990 - 2000 – 2010 - 2020
Max Shelton
Scott Dalzell
Ben Mullen
Chris Lambrides
Jim Brewbaker, Charles
Sorensson (UH)
Hayley Giles, Michael Halliday,
Nahuel Pachas
Lachlan Robertson, Andrew
Hacker,
Gerado Solis, Alex Radrizzani (LA)
Greg Brown & Ross Gutteridge
Juliette Warnick-Hayne, Dave
Flatley
Many other students, workers and
helpers
3. Leucaena R&D&E in Australia & University of Queensland (1990-2017)
Seven major R&D programs
3.1 Leucaena germplasm evaluation
Long been botanical interest in the Leucaena genus (OFI, UH) – Monograph published by OFI
Recognise 22 species including natural hybrids
Arrival of leucaena psyllid in mid 1980s created impetus to study agronomy and nutritive value of entire genus
L. leucocephala (4n)
L. pallida (4n)
L. diversifolia (4n)
L. trichandra (2n)
L. collinsii (2n)
L. esculenta (2n)
L. macrophylla (2n)
L. salvadorensis (2n) L. retusa
Leucaena spp. seed collected from multiple collection trips by US, UK and Australia to Mexico and Central America from ~1950, held in 5 international seedbanks
• SARDI, South Australia
• CIAT, Colombia
• ILRI, Ethiopia
• UH, Hawaii
• OFI, UK
3.1 Leucaena germplasm evaluation
UQ Genotype x environment trials (1995-2000) (Ben Mullen)
Multi-environment trials (25 representatives from 116 accessions, representing 14 spp. and 2 interspecific hybrids
Planted at 18 sites, 7 countries, representing wet/dry, low/high psyllids, hot/cool, and acid soil environments
Data analysed by ANOVA and for Genotype x Environment interactions
Mean DM yields in 8 environments (Mullen 2001)
0
100
200
300
400
500
600
Gr 1 (1) Gr 2 (1) Gr 3 (1) Gr 4 (8) Gr 5 (9) Gr 6 (2) Gr 7 (17) Gr 8 (22)
Environment groups
DM
yie
ld (
g/m
ro
w/
mo
nth
)
IRRI
Unitech
Sungei Putih
Hot/wet &
low psyllids
Hot/mod rain
& low psyllids
Highland
tropical
& low psyllids
Acid infertile
or cold or dry
& high psylids
Dry or cold &
high psyllids
Very hot &wet &
low psyllids
Mean DM yields of 7 accession groups (Mullen 2001)
0
100
200
300
400
500
600
Gr 1 (1) Gr 2 (3) Gr 3 (4) Gr 4 (5) Gr 5 (1) Gr 6 (7) Gr 7 (4)
Accession groups
DM
yie
ld (
g/m
ro
w/
mo
nth
)
KX2 F1
K636
KX2 F5
CQ3439
OFI 53/88
OFI 47/87
OFI 79/92
OFI 52/87
OFI 47/85
OFI 52/88
KX3 F2
OFI 43/85
Cunningham
OFI 36/88
OFI 56/88
CPI 46568
OFI 83/92
K156
OFI 6/91
OFI 19/84
OFI 61/88OFI 82/92
OFI 4/91
OFI 87/92
OFI 83/87
Hybrid was high yielding
Most tree legumes, including Leucaena spp., contain tannins
Good: by-pass protein (L. leucocephala)
Bad: reduce overall digestibility of protein (Calliandra, Acacia, Flemingia, Prosopis, L. pallida)
L. collinsi
L. pallida
L. leucocephala
3.2 Leucaena spp. Forage quality Tannins and digestibility of (Scott Dalzell)
Protein binding (astringency) of CT varies with species, and reduces digestibility of most Leucaena spp. (McNeill et al. 1998)
L. leucocephala
L. pallida
3.2 Leucaena spp. Forage quality Tannins and digestibility of (Scott Dalzell)
5 = 25%CP/5% CT
Animal productivity low in high CT Leucaena spp.
High CT spp. (L. pallida) are poorer in LWG (Galgal, 2000)
230.0
240.0
250.0
260.0
270.0
280.0
290.0
300.0
27-M
ar
3-Apr
10-A
pr
17-A
pr
24-A
pr
1-May
8-May
15-M
ay
22-M
ay
29-M
ay
5-Ju
n
12-Jun
19-Jun
26-Jun
3-Ju
l
10-Jul
Date
Cu
mu
lati
ve
liv
ew
eig
ht
(kg
)
L. leucocephala
KX2 hybrid
Signal grass
L. pallida
3.3 Varietal release and plant breeding
Leucaena cultivars
• Peru and Cunningham (1960s)
• Tarramba (1996)
• Wondergraze (2011)
• Redlands (psyllid resistant) (2015)
The leucaena psyllid
Heteropsylla cubana Psyllid damage
Breeding ‘Redlands’ - psyllid resistant leucaena (2002-2015)
Natural predators
L. Pallida
10% L. Leucocephala
90%
Breeding program based on interspecific hybrid between L. leucocephala and L. pallida
Leucaena preference trial –North Queensland (Compared preference of cattle for Redlands + 3 breeding lines with
Cunningham & WonderGraze X 8 replications)
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
12 24 34 39 C W
Leaf
(kg
DW
/plo
t)
Leucaena variety
Leaf DW prior to grazing (kg/plot)
Leaf DW consumed (kg/plot)
Redlands Cunningham Wondergraze
cv. Redlands June 2017
3.4 Plant nutrition – Phosphorus and sulphur
0.140.120.100.080.060.040.020.00
5.0
4.5
4.0
3.5
3.0
2.5
2.0
(PxS index)
Nit
ro
ge
n c
on
ce
ntra
tio
n in
YFEL (
%D
M)
4
Marginal
P & S are deficient
P&S are OK
S is OK, P deficient
P and S play key role of in nitrogen fixation
P and S status of leucaena leaves
Deficient
Adequate
Leucaena fertilized with S
Experiment was conducted to test effect of leucaena density and row spacing on relative proportion of leucaena and grass
3.5 Leucaena plant density and legume-grass balance
Row spacing varies from 5-15m
“A study of the water
use in leucaena-
grass systems”
GLNG Project
Tree densities and grass competition studied using a Nelder fan design
Pachas, ANA, Shelton HM, Lambrides CJ, Dalzell, SA, Murtagh GJ.
80,000 trees/ha
8,616 trees/ha
928 trees/ha
100 pl/ha
Rhodes grass
Rhodes grass
Percentage of grass/legume
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
2.0 2.3 2.6 3.0 3.3 3.6 3.9 4.3 4.6 4.9
Pe
rce
nta
ge
ed
ible
bio
ma
ss (
%)
Log density (trees/ha)
Leucaena
Rhodes grass
Mexico
Colombia
Indonesia
Up to 8000 trees/ha
Australia
1500 trees/ha
3.6 Animal studies in Australia
Live weight gains
Leucaena toxicity (new hypothesis presented)
3.6 Live weight gains
We know that leucaena has:
High crude protein content (~20% CP in forage)
High content of essential elements
Very high palatability and digestibility
Gives ‘by-pass’ protein
Anthelmintic properties
Forage system
(700 mm rainfall)
Stocking
rate
(ha/steer)
Weight gain (kg/year)
(per/steer) (per ha)
Buffel grass 2 170-190 85-95
Leucaena – buffel grass 1.2 250-300 210-250
High live weight gains
(without supplement)
x1.5 X1.5 X2.5
Excellent weight gains due to high forage quality
Production data for 2013 from Taroom Rancher, Queensland
Total cattle Avg carcass Wt Days owned Wt gain/yr Wt gain/day
2929 345kg 384 days 285kg 0.82kg
3.6 Animal studies - Leucaena toxicity
Background Research into Toxicity
▶ Leucaena contains mimosine (very toxic)
which degrades to DHP (chronically toxic) in
ruminants
▶ Australian CSIRO scientist, Dr Raymond
Jones (1970-2000), discovered a rumen
bacterium that degraded mimosine and DHP
— thought to be unique and novel to specific
countries.
▶ Named Synergistes jonesii, it was discovered
in Indonesia and Hawaii; later brought to
Australia and distributed to ranchers.
From 2003-2016, UQ hand-collected 100s of rumen fluid and 1000s of urine samples from Australia, Indonesia, Thailand,
Mexico
What we discovered was: S. jonesii indigenous across all
geographical regions and ruminant spp tested, regardless of consumption of leucaena.
S. jonesii present in low populations, too low to degrade high leucaena diets.
In Thailand, Indonesia, Mexico, 1000s of urine samples from goats / cattle consuming 100% leucaena had very high levels of 2,3-DHP in their urine.
DHP not degraded by S. jonesii , but animals were healthy and gaining weight.
DHP was being neutralized (conjugated) by compounds produced in liver and excreted in urine.
Our new hypothesis: Inoculation may not be necessary
= New Hypothesis for management of toxicity
(Halliday, Phaikaew, Shelton, McSweeney, Kerven, Jag)
Urine samples showing undegraded DHP
3.7 Education training and adoption
Since 2004, UQ conducted:
30 courses in Aust. for >500 ranchers
Farm of Mr Muin who has planted 6ha of Tarramba leucaena for bull fattening (Sumbawa)
Farmer in village of Jati Sari on Sumbawa - fattening bulls with leucaena is profitable business
3.7 Worked on adoption of Tarramba leucaena for
cattle fattening in Indonesia (2011-2016)
4. Environment issues
Negative issues
• Weediness
• Leucaena spreads between rows when poorly managed
• Escapes to become a weed along roads and water courses
• New MLA project to produce a sterile leucaena
Positive issues • Protects against drought
• Sustainable farming system
• Organic beef
• Erosion & water quality control
• Sequesters C and reduces methane production
• Renewable power generation
• Improved Animal welfare (dry season feed available, internal parasite control)
5. Continuing research priorities Toxicity – confirm
conjugation of DHP occurs in other countries and other ruminant spp.
Research anthelmintic value of leucaena for ruminants, non ruminants, humans)
Thank you Please
feed me
leucaena