APMed (hAPpyMed
)
Apple and Peach in Mediterranean orchards –
Integrating tree water status and irrigation
management for coping with water scarcity and
aphid control
ARIMNET meeting – Montpellier, France – June 11-12, 2014
APMed – Context – Teams - Topics and WPs – First results - 2014
Context and choices
1 - Water scarcity: most studies on annuals (yield… molecular)
 Perennials: effects in the same year AND in the following years.
 Fruit tree: fruit quality AND regularity of bearing.
Apple and Peach.
The economic point of view: trend towards high added-value in
terms of price evolution in past years (FAO stats):
2000-2006 -> 2009: 100 -> 138 (Apple) / 146 (Peach)
100 -> 94 (Olive)
 The technical and scientific points of view: strong interlacing
between vegetative and fruit compartments, and phenology
-> several levels
1) fruit load, number of shoots/tree to alleviate water stress (eg,
fruit thinning, pruning)
2) Irrigation scheduling depending on the phenological stage
APMed – Context – Teams - Topics and WPs – First results - 2014
Context and choices
2 - Water affects fruit and shoot growth
= It affects the water and nutrient status of all plant organs
 To what extent does it affect pest infestation?
Controversies in the literature: Aphid performance is affected either
positively or negatively … or not at all.
 compromise between defense / growth / storage
Plant vigor Hypothesis (PVH) : Aphids feed on actively growing tree/shoots because of
- (i) increased turgescence
- (ii) increased sap flow
- (ii) higher sugar and AA [] in the phloem
 Scientific premise: aphids as competing sinks
 Innovative point: infestation dynamics may be affected by the water
management strategy which determines tree/shoot growth,
tree/shoot water and nutrient status
APMed – Context – Teams - Topics and WPs – First results - 2014
France: INRA Avignon
MO Jordan, MH Sauge, G Vercambre, F Lescourret
France: INRA Montpellier
PE Lauri, E Costes, JL Regnard
Spain: IRTA Lerida
J Girona & team
Italy: University of Bologna
L Correlli-Grappadelli & team
Morocco: INRA Kenitra
S Charif
Morocco: INRA, ENA and University Meknès
A Blenzar, A Kajji, A Boutaleb
Israel: MIGAL-Northern R&D
A Naor, H Reuvny
APMed – Context – Teams - Topics and WPs – First results - 2014
Topics and WPs – general outlines
WP1
Genetic variability
to water restriction
WP2
Tree – aphids
interactions
WP4
Modelling
Integrating
knowledge in FSPM
WP3
Water management
in the orchard
APMed – Context – Teams - Topics and WPs – First results - 2014
WP1
WP1
Genetic variability
to water restriction
Exploring the range of adaptations to drought observed among Apple progenies,
focusing on growth, and leaf and stem ecophysiology.
WP leader – Pierre-Eric Lauri – INRA Montpellier, France.
Partners: Luca Corelli-Grappadelli – University of Bologna, Italy.
- First, to analyze across a range of genotypes without interference with fruit load the
range of variations of leaf ecophysiology and xylem hydraulic traits.
- Second, to analyze how these traits simultaneously interact with shoot morphology
and leaf development to increase tolerance to soil water restriction.
- Towards morphological and ecophysiological criteria to integrate in selection
schemes + comparisons with the adult tree (methodology).
APMed – Context – Teams - Topics and WPs – First results - 2014
WP1 - Morphology
Shoot morphology
Separate stem and leaf
- Stem: growth arrest, length,
number of nodes, diameter…,
- Leaf: individual leaf area, SLA…,
total leaf area (individual leaf area
& number of leaves).
Hypothesis: Water Stress may affect
differently these shoot compartments
 Genetic variability implies that
within certain limits, we can search for
general correlations
&
possible absence of correlations.
Need to differentiate between mild
(50% FTSW) and severe (20% FTSW)
water stress
The genotype had the stronger effect
during the 50% of FTSW period.
The water regime had the stronger
effects during the 20% FTSW period
and lo a lesser extent during the 50%
FTSW period.
APMed – Context – Teams - Topics and WPs – First results - 2014
Growth arrest  number of nodes
Rather similar ranking of genotypes in mild and severe water stress
Individual leaf area: reduction with water stress but interaction with the environment
Indiv. leaf area - WS/WW ratio in
Outdoor environment
1.2
50% FTSW
More growth reduction in
20% than in 50%.
20% FTSW
1
125
37
57
117
96
23 7 106
48 70
41 54 4035
SK 38
97
38
26
GS
121 111
96
40
2337 57 125
SK 117 106
7 97
111
70
121
35
26
54
0.8
0.6
0.4
0.2
Quite similar reduction for
individual LA in the two
environments (tendency for
G>O) ≈ stable trait.
GS
0
0
0.2
41
48
0.4
0.6
0.8
1
Indiv. leaf area - WS/WW ratio in Greenhouse environment
Combining GA and LA:
Genotypes 125, 70: lowest decrease of indiv. LA and low GA  low decrease of total LA
Genotype 121: high decrease of indiv. LA and high GA  high decrease of total LA
APMed – Context – Teams - Topics and WPs – First results - 2014
WP1 - Ecophysiology
Towards a fast method to evaluate leaf functioning under various water regimes?
Predicted:Observed:
r2 = 0.9146;
r = 0.9564;
p = 00.0000;
= -0.0058 + 1.001*x
Scatterplot (Spreadsheet
in multiple
regression
delta t 2.0y9v*316c)
Combining fluorescence
(Phi PSII) and Leaf
temperature as predictor
variables
 The IPL index
(multivariate regression
approach)
(Losciale et al., submitted)
Observed = -0.0058+1.001*x
18
16
14
Pn Observed
12
10
8
6
4
2
0
-2
-2
0
2
4
6
8
10
12
14
16
18
Pn Predicted [IPL]
Ongoing works on 2012 and 2013 data: determination of
morphological and ecophysiological traits under water stress.
APMed – Context – Teams - Topics and WPs – First results - 2014
Topics and WPs – WP2
WP2
Tree – aphids
interactions
Impact of water availability on aphid infestation in relation to (i) shoot and fruit growth, and
(ii) plant water and nutrient status, on Apple and Peach.
WP leader – Marie-Odile Jordan - INRA Avignon, France.
Partners: Morocco - Abdelali Blenzar, University of Sciences, Meknes - Moulay Chrif Smaili,
INRA Kenitra; Israel - Haim Reuveny, Northern R&D/MIGAL.
- First, to analyze aphid population dynamics in various water management contexts thanks to
surveys conducted in commercial orchards.
- Second, to estimate the phloem sap composition and availability for the aphid on young
potted trees in relation to the competing fruit sink (stylectomy and biochemical analysis).
- Third, to evaluate the relative effect of plant growth and nutrient status on plant resistance to
aphids in relation to water management.
APMed – Context – Teams - Topics and WPs – First results - 2014
Variability of infestation dynamics and responses to water stress
Correlation between N and water supply !!!
0,7
0,6
T1 Control
T2 Stressed (80%)
N- H100
0,8
N- H0
IF Index
IF Index
0,5
1,0
N+ H100
0,6
N+ H0
0,4
0,3
0,4
0,2
0,2
0,1
0,0
May 17
May 30
June 13
June 27
0
2/5/13
25/5/13
19/6/13
2/7/13
17/7/13
APMed – Context – Teams - Topics and WPs – First results - 2014
 (point 3) and to plant functionning: growth, water and nutrient status
Interaction between the effects !
High P.
High N trees:
0,8
-  with water stress
Low N trees
H N+ H0
0,6
M N+ H0
L N+ H0
Low, medium P.
0,4
- no effect of water stress
Pruning int.
H N+ H100
M N+ H100
-  IF and individual shoot growth
L N+ H100
H N- H0
0,2
M N- H0
L N- H0
0,0
10
12
14
16
18
20
22
Nb proleptic leaves
24
26
28
H N- H100
M N- H100
L N- H100
Aphid number log(n+1)
IF at infestation peak
1,0
30%
65%
100%
Leaf N [ ] at infestation
APMed – Context – Teams - Topics and WPs – First results - 2014
 (point 1) related to environmental conditions !
Climate : wind, temperatures, radiation ….
Entomofauna: surrounding plants, hedges …
Cultural practices ….
0,18
0,15
0,09
0,06
W
5
0,5
4
0,4
3
0,3
2
0,2
1
0,1
0
IF index
S
Ouest
E
Nb individuals
N
Sud
W
Est
S
Nord…
E
Ouest
N
Sud
0
Est
0,03
Nord…
IF index
0,12
0
2/5/13
25/5/13
19/6/13
Coccinelle 7 points
Syrphes
C. Septempuntata
Syrphidae
2/7/13
Chrysopes
Chrysopidae
17/7/13
Stethorus
Stethorus
IF T2
APMed – Context – Teams - Topics and WPs – First results - 2014
(point 2) Comparing Stylectomy, Enhanced exudation and Shoot grindings
3 modalities of continuous water deficit
Control (100% of field capacity)
Moderate (66%)
Severe (33%)
Indicators of plant growth and water status
Shoot length, growth speed
Leaf emergence
Predawn water potential
Composition of phloem sap (stylectomy)
Comparison of 3
sampling methods
200
150
60
20
40
[AA tot] (mM)
Exudate
0.4
0.3
0.5
80
100 50
0.7
0.6
0.5
1.5
1.0
[M]
100%
66%
33%
100
Sucrose
2.0
Sorbitol
[AA tot] (mM)
Stylectomy
Glucose and Fructose:
 Quantities inferior to the quantification limit
250
Sugars
100% 66%
33%
100% 66%
33%
Sorbitol: 1.16 M ; Sucrose: 0.68 (Moing et al. 1992)
0.2
0.4
0.6
0.8
1.0
1.2
[AA tot] (% of dry matter)
Grinding
APMed – Context – Teams - Topics and WPs – First results - 2014
WP3
Improvements of water and N management techniques according to their ability to maintain
high quality of fruit production and reducing aphid infestations on Apple and Peach.
WP leader – Luca Corelli-Grappadelli – University of Bologna, Italy.
Partners: Israel - Amos Naor, MIGAL; Morocco - Bniken Lhou, INRA Kenitra - Abdellah Kajji,
ENA Meknes; France - Pierre-Eric Lauri, INRA Montpellier, with sub-contractants: Bruno
Hucbourg, GRCETA, and Xavier Crété, CEHM.
Around the Regulated Deficit Irrigation (RDI) concept.
- First, tree growth and fruiting under various degrees of water restriction, and management
techniques (crop load, orchard light conditioning, nitrogen fertilization), and taking into
account the phenological stage -> thresholds to manage irrigation.
- Second, comparison between one-year-old shoots and adult trees.
WP3
Water management
in the orchard
APMed – Context – Teams - Topics and WPs – First results - 2014
Task 1 –
MANAGING LIGHT CONDITIONS
•In apple, shading reduces water use
without affecting leaf photosynthetic rates,
nor harvest fruit quality and yields.
•Thus, the use of shading nets can allow
the application of deficit irrigation
scheduling without affecting tree
performances.
MANAGING FERTIGATION
•Reduced water and N applications
negatively affect fruit size and yields.
•However, mild deficit fertigation can
improve fruit sugar content without a
proportional loss in fruit size
MANAGING CROP LOAD
•High crop load negatively affects fruit size,
colour and return bloom
•However, commercial crop yield increases
with increasing crop load to a maximum
threshold that is proportional to irrigation
level
Task 3.2: Main results
November, 4-6, 2013, ApMed General Assembly, Bologna, France
Task 1 – Can we infer the behaviour of adult trees from
the performance of young plants?
Water stress tolerant
Water stress susceptible
greenhouse, one- 7,38,41,48,54,70,96,97,1 23,26,35,37,40,57,111,117,12
year-old plants
06,125
1,gs,stk
7,23,26,35,37,38,57,96,9 40,41,48,54,70,106,111,117,1
field, adult trees
7,121,gs,stk
25
Common
results
7, 38,96,97
40,111,117
• 7 genotypes out of 21 behaved in the same way as young or adult fruiting
trees.
• Discordance between young and adult plants might be due both to
difficulties in replicating the water stress protocol, and to the influence of
fruit on the tree.
APMed – Context – Teams - Topics and WPs – First results
WP4
Modelling water and N management techniques according to their ability to maintain
high quality of fruit production and reducing aphid infestations on Apple and Peach.
WP leader – Joan Girona – IRTA, Spain.
Partners: France - Evelyne Costes, Françoise Lescourret, Gilles Vercambre, INRA. All WPs.
- Challenge: to bridge various modelling approaches based on metabolic compartment
(QualiTree) and on plant architecture (MappleT, L-Peach).
- To implement the various modules (water transport and nutritional processes, aphid
infestation responses etc.) in the existing models = to integrate knowledge developed
during the programme, and to validate and assess their interests.
- Post-Doc recruited in the APMed (ca. 20 months).
WP4
Integrating
knowledge in FSPM
Modelling
=
+
+
APMed – Context – Teams - Topics and WPs – First results
Plant water status through transpiration
• from fraction of intercepted light + Kc
• from water transport within the tree
MAppleT
QualiTree
Marsal et al. 2014. Fraction of canopy intercepted radiation relates
differently with crop coefficient depending on the season and the fruit
tree species. Agricultural and Forest Meteorology 184: 1-11.
Simulated water stress effects
Guillaume O. 2013. Adaptation et paramétrisation du modèle QualiTree au pommier sur la base d'architecture 3D générées par le modèle MAppleT. Montpellier SupAgro.
Current field experiments will improve those preliminary results through
• Effect of the plant water status on vegetative and fruit growth and quality (2014)
• Calibration and validation (after the end of the APMed programme)
APMed – Context – Teams - Topics and WPs – First results
INRA Région PhD grant (A. Rousselin)
Relation
between plant
tolerance to
water stress
and resistance
to aphid?
Comparison
between pot and
field experiments
Comparison between
young shoots (hybrid
selection) and adult trees
TUBITAK post doc
(Ersin Atay) from Turkey
KOM – Peach Orchard near Montpellier – 17 October, 2012
APMed – Context – Teams - Topics and WPs - 2014
Programme launched on April 1, 2012, in France but later for
the other countries
Regular exchanges between countries within WPs and
coordination between WPs
Annual meetings:
 Kick-Off meeting, Montpellier, France, 15-18 October 2012
 Second meeting, Bologna, Italy, 6-6 November 2013
 Third meeting, Lerida, Spain, scheduled for January 2015
Public meeting, likely in SE France, in June 2014. In
collaboration with Growers association, open to scientists,
engineers and technicians from extension services and
experimental stations