1. MORPHOLOGICAL PLASTICITY IN WHEAT (Triticum aestivum L.)
ROOT DEVELOPMENT UNDER PEG- TREATED HYDROPONIC CULTURE Supervisor
Dr. Arif Hasan Khan Robin Associate Professor Co-supervisor Dr. Md.
Abdullah Al Bari Associate Professor Presented by ID: 14AgGPB JJ02
M Reg. No.: 36293 Department of Genetics and Plant Breeding
Bangladesh Agricultural University
2. Presentation Outline Introduction/background of the study
Objectives of the study Materials and Methods Results Discussion
Conclusions References Acknowledgements
3. Background Wheat is a vital crop and among cereals it stands
next to rice and maize. It grows in 0.43 million ha in rabi season
and production is around 1.3 M ton in our country In Bangladesh,
wheat yield ranges from 4.5 to 5.5 t ha-1 Potential yield is more
than 9 t ha-1 Sources: FAOSTAT 2013; BBS, 2014; USDA, 2014; BARI,
2015
5. Background (Contd) Wheat production is greatly affected by
drought in the country Grain yield of wheat reduced upto 50-66%
during reproductive stage, 18-53% at pre-anthesis and 13-38% at
post-anthesis. Efficient root system can exploit residual soil
moisture to avoid drought stress. Polyethylene glycol (PEG) can
successfully create drought condition at hydroponic culture
Sources: Michel and Kaufmann, 1973; Majid et al., 2007; Kili and
Yabasanlar, 2010
6. Background (Contd) So, three hydroponic lab experiments with
PEG-8000 treatment was conducted in this research Fig. 1 Root
architecture in wheat 1. Primary root; 2. First order lateral root;
3. Secondary order lateral root; 4. Branching interval; 5.
Adventitious root; 1. Primary root branching angle; 2. First order
lateral root branching angle; 3. Secondary order lateral root
branching angle. 1 2 3 4 5 1 3 2
7. Objectives To investigate the effect of 0.5% PEG-8000
mediated stress on seminal wheat root development To explore the
outcome of prolonged stress by PEG-8000 on lateral roots and on
root hairs of adventitious roots To perceive the responses of high
resolute PEG-8000 on root growth during booting stage of
wheat.
8. Materials and Methods Experimental site and periods with
spell Growth chamber, Dept. of GPB, BAU. Duration April to November
A hydroponic experimentation Three subsequent experimentation was
conducted. Experimental Design Completely randomized design(CRD).
Plant materials and sources Ten (10) elite wheat varieties.
Collected from Wheat Research Centre, Bangladesh Agricultural
Research Institute (BARI)
9. Materials and Methods (Contd) Variety Released year Yield (t
ha1) Features BARI Gom 21 (Shatabdi) 2000 3.65.0 Good level of
tolerance to terminal heat BARI Gom 24 (Prodip) 2005 4.35.1 High
yielding, but heat sensitive BARI Gom 23 (Bijoy) 2005 4.35.0
Moderately heat tolerant BARI Gom 25 2010 3.65.0 Moderate level of
tolerance to heat stress BARI Gom 26 2010 3.55.0 Tolerant to
terminal heat stress in late seeding BARI Gom 28 2012 4.05.5
Tolerant to terminal heat stress in late seeding Kheri Indigenous
cultivar Sonalika 1973 1.72.1 Kanchan 1983 3.5 4.6 Leaf rust
susceptible Akbar 1983 3.5 4.5 Leaf rust tolerant Table 1.
Characteristics of the selected wheat varieties
10. Materials and Methods (Contd) Germination of seeds On
polystyrene sheets inside the trays in the growth chamber, temp
2020 C and light 572 PPFD. After 2-3 days germination occurred.
Fig. 2 Germination of seeds on polystyrene sheets.
11. Materials and Methods (Contd) Seedling raising and
transferring into hardwood sheet After one week seed were grown in
seedling. Timely nutrient supply and thinning was done. Then
transferred into hardwood sheet. A B Fig. 3 A) Seedling raising; B)
Transferred seedlings into hardwood sheet
12. Materials and Methods (Contd) Nutrient solution Modified
Hoagland solution. Electrical Conductivity (EC) is maintained to
0.6-1.0 Table 2. Composition and concentration of the minerals used
in the solution Components Concentration NH4NO3 62.46 mM
NaH2PO4.H2O 43.48 mM MgSO4 39.46 mM KNO3 59.35 mM CaCl2.H2O 16.12
mM H3BO3 3.43 mM MnSO4.4H2O 0.76 mM ZnSO4.7H2O 0.059 mM or 59.12 M
CuSO4.5H2O 0.039 mM or 39.47 M NaMoO4.2H2O 0.009 mM or 9.13 M FeSO4
16.46 mM EDTA 10.27 mM
13. Materials and Methods (Contd) PEG treatment Fig. 4
Controlled condition (0.0% PEG) Fig. 5 Treated with 0.5% PEG Table
3. PEG application time and duration in the experimentations
Experiment Concentration Treatment given DAT Duration of treatment
Seminal 0.5% 20 10 Adventitious 54 20 Booting stage 75 20
14. Materials and Methods (Contd) Data recording Harvest 1: At
30 DAT during seminal root formation Harvest 2: At the 67 DAT
during adventitious root formation Harvest 3: At 97 DAT during
reproductive stage or booting stage Preparation of Safranin Stain
Solution Safranin solution of 0.5% was used for staining root hairs
Measured variables Live leaves Number of primary axis root Main
axis root hair number Secondary axis root hair number Growth status
Primary root axis length Main axis root hair length Secondary axis
root hair length Total root number Primary root axis diameter Main
axis root hair diameter Secondary axis root hair diameter Number of
phytomer Number of secondary root axis Primary axis root hair
number Root dry weight Main root axis length Secondary root axis
length Primary axis root hair length Shoot dry weight Main root
axis diameter Secondary root axis diameter Primary axis root hair
diameter Chlorophyll content
15. Materials and Methods (Contd) Measurement of traits under
microscope The measurements were done at 40x and 100x
magnifications under microscope. Fig. 6 Measurements of root traits
under microscope. a) diameter of main axis root under control
condition; b) diameter of PEG-treated main axis root; c) number of
lateral roots under controlled condition; d) lateral root numbers
under PEG-treated condition; e) number of root hairs under
controlled condition; f) number of root hairs under PEG
treatment.
16. Materials and Methods (Contd) Root dry weight and shoot dry
weight Roots and shoots were put in the oven with envelop and kept
at 600 C for 7 days Chlorophyll content measurement With
Chlorophyll meter (SPAD502 Plus, 3V; 200mW), chlorophyll content of
live leaves were measured. Statistical analysis Data were analyzed
using MINITAB 17 statistical software packages. Fig. 7 Chlorophyll
content measurement
17. Results Length of root hair at seminal root formation Fig.
8 Length of root hairs originated at the main root axis of wheat
varieties for two PEG treatments on 10 days after two (0.0% and
0.5%) PEG treatment (P