Strategies for Enhancing P Nutrition in Crops Flashcards
1
Q
Structure
A
1.
2.
3.
2
Q
Increasing crop PAE under low Pi approach 1
A
- genetic screen for rice varieties.land races w/ low Pi tolerance
- O. sativa indica Kasalath cultivar; O. sativa aus
3
Q
Pup1
A
- major QTL for Pi-deficiency tolerance
- marker-assisted breeding
4
Q
PSTOL1
A
- Phosphorus Starvation Tolerance 1
- Pup1 functional gene (causative); expression profile
- cytoplasmic RK
- “high-value”
5
Q
PSTOL1oe in intolerant Nipponbare
A
- increased PAE
- increased tolerance
- increased grain weight, P content, root dry weight (p<0.05)
6
Q
Mechanism of PSTOLoe?
A
increased root growth
7
Q
Increasing crop PAE under low Pi approach 2
A
- understand PAE mechanism
8
Q
PHT1oe in O.s. and G. m.
A
- increased grain weight
- increased yield
9
Q
pho2 in wheat
A
- increased uptake
- increased grain yield
10
Q
miRNA 399oe in tomato
A
Pi toxicity
11
Q
oe
A
- liable to toxicity
- targeted PT PHT1 control
12
Q
PHF1oe in O.s.
A
- increased yield (33P uptake [micromoles per gram of root fresh weight]
- increased grain weight
- compared to empty vector control
13
Q
Increase crop PUE under low Pi approach : PHR1oe in wheat;
A
- increased PSR
- increased PAE (shoot Pi)
- increased PUE (LRB, shoot development, seedling RB, GY)
14
Q
LRB
A
lateral root branching
15
Q
seedling RB
A
root biomass
16
Q
OsPHR3oe
A
- increased PAE
- increased shoot uptake
17
Q
OsPHR2oe
A
- decreased shoot biomass
- stunted growth
- decreased tiller no.
- decreased RB
- toxicity!
18
Q
PHO1oe
A
- increased grain filling
- increased grain yield
19
Q
pho1/2 in rice, maize
A
- decreased grain starch filling
- decreased grain weight
- p<0.005
20
Q
PHO2oe
A
- increased grain weight
- increased AGPase activity (micro moles.min/g FW)
21
Q
AGPase
A
- ADP-glucose phosphorylase
- suppressed by Pi
- regulated by PHO1
22
Q
agriculture
A
~10,000 ya (recent)
23
Q
modern varieties
A
- ~50ya
- intensive breeding
24
Q
A shift from wild to cultivation may have a
A
- negative impact on the capacity of crop plants to benefit from AMF interactions
- compare 13 modern wheat varieties with 7 related accessions
25
AMF diversity
- decreased in agricultural soils
26
Why is AMF diversity decreased in agricultural soils
1) fertiliser overuse
2) pesticide
3) tillage
4) long fallow periods
5) crop rotations
27
extra-radical hyphal network
- disturbed in the agricultural setting
- long periods where AMF have limited host access
- C: unstable
28
GA
- negative regulator of AMS
- plant breeding target
29
GR
selection of semi-dwarf varieties of wheat, rice and sorghum; generated by targeting plant hormones under high Pi
30
RSA
- varies in agriculture
31
D8
- Dwarf8
- positive effect on AMF
- global (temperature + tropical)
- high yielding
- GA-biosynthetic mutant
- dominant Rht alleles
32
Rht
- reduced height
- GR crop varieties
- degradation resistant DELLA proteins
- GA-insensitive
- decreased shoot growth, increased grain yield
33
della/GAoe/exogenous GA app in Mt
- decreased arbuscule
- increased growth
34
della/GAoe/exogenous GA app in Os
- decreased AMS colonisation
35
rht1/2
- increased AMF colonisation
- increased shoot Pi
- no increased in shoot biomass or FW (due to DELLA suppression)
36
PHR-SPX module
- connects plant Pi status with/ arbuscule development and function
- necessary
37
phr1
- decreased total and arbuscule root length colonisation (p<0.01)
- small, stunted?
38
spx, PHR1oe
- overcome inhibition
- increased root length colonisation (%)
39
AMS benefits in agriculture
- contentious
40
Benefit QTLs in Z. mays field experiment
- medium-input, rain-fed, tropical
- maximise AMS advantage
- Castor?
41
castor in the greenhouse
- AMF-R
- no effect on growth and development
- no significant morphological difference compared to baseline performance control
42
castor in the field?
- decreased growth yield (30%)
- decreased plant height (p<0.01)
- decreased total kernel no. (p<0.01)
43
Having AMF contributes?
~2 tonnes/h
