RESARCH METHODS TO KNOW THE EFFECT ON ANTIOXIDENT DEFENSE SYSTEM ON SPRING MAIZE UNDER LOW TEMPERATURE STRESS

1. EFFECT OF HYDRO- AND HORMONAL PRIMING ON ANTIOXIDANT
DEFENCE SYSTEM OF SPRING MAIZE UNDER LOW TEMPERATURE
STRESS.
Major Advisor M. Shilpa
Dr. Kamaljit Kaur L-2017-BS-240-M

2. INTRODUCTION
 Maize (Zea mays L.) belongs to Gramineae family and serves as
major staple food in many parts of the world with total production
103.77 million tonnes in the world.
Spring maize cultivation plays a key role in crop diversification.
However, the major limitation in its cultivation is that it gets exposed
to high temperatures at anthesis which leads to poor growth and
productivity.
To avoid heat stress at later growth stages, early sowing of the crop
is preferred. However, early sown crop gets exposed to low
temperature stress that results in reduced germination percentage,
decreased seedling growth and yellowing of leaves thereby affecting
yield and productivity of the crop at maturity.

3.  Chilling injury causes curling and crinkling of leaves, reduced seed
emergence yellowing/ purpling of leaves
 An increase in reactive oxygen species (ROS) that causes severe
oxidative damage to the plants
 Stress tolerance has been reported to be linked with antioxidant
defence system of the plants.
 In this perspective, if hydro or hormonal priming could help plants
in maintaining their redox homeostasis under stress conditions, they
would enhance their stress tolerance potential.

4. KNOWLEDGE GAP
Review of literature reveals that hydro- and salicylic acid
priming improve germination percentage and seedling vigour in
spring maize exposed to chilling stress (Rehman et al 2015).
However, relatively little is known about their effects on
antioxidant defence system of spring maize under low temperature
stress.

5. OBJECTIVES
 To study the effect of hydro- and hormonal priming on growth
parameters.
 To study the effect of hydro- and hormonal priming on
antioxidant defence system of spring maize under low
temperature stress.

6. EXPECTED NEW KNOWLEDGE
 This study will provide information about the potential of hydro- and
hormonal priming of seeds in modulating antioxidant defence system of
spring maize under low temperature temperature stress.

7. METHODOLOGY
Maize genotypes susceptible and tolerant to the low
temperature stress, PHM-2 and PHM-9 respectively will be
procured from the Department of Plant Breeding and Genetics,
Punjab Agricultural University, Ludhiana.

8. EXPERIMENT NO : 1
i. Name of the experiment: Effect of hydro- and salicylic acid priming on
growth parameters of spring maize under low temperature stress.
ii. Location of the work: Department of Biochemistry and Department of
Plant Breeding and Genetics, Punjab Agricultural University, Ludhiana.
iii. Methodology: Maize seeds will be primed with water or 50 mg L-1
salicylic acid for 18 hours, air dried and then sown in the fields of Plant
Breeding and Genetics by 10th of January in randomized block design in
a replicated manner. The untreated seeds will be taken as control.
 Germination percentage, germination index and mean germination time
will be determined. Length and biomass of shoots and roots will also be
determined after one month of sowing.

9. iv. Observations to be recorded: Germination percentage,
germination index, mean germination time, length and
biomass of shoots and roots will be recorded.
v. Statistical analysis: Results will be analysed by applying
Duncan’s multiple range test (DMRT) at 0.05% level of
significance.

10. EXPERIMENT NO : 2
i. Name of the experiment: Effect of hydro- and hormonal priming on
antioxidant defence system of spring maize under low temperature stress.
ii. Location of work: Department of Biochemistry and Department of Plant
Breeding and Genetics, Punjab Agricultural University, Ludhiana.
iii. Methodology: Maize seeds will be sown as described in Experiment No.1.
The activities of antioxidant enzymes viz., catalase, ascorbate peroxidase,
peroxidase, superoxide dismutase, glutathione reductase (Kaur et al 2009)
and polyphenol oxidase (Zauberman et al 1991) will be extracted and
estimated from the leaves of seedlings at 10, 20 and 30 days after sowing
(DAS) stages.
 The contents of H2O2, malondialdehyde, ascorbic acid, proline and total
phenols (Chugh et al 2011; Rana et al 2006) will be extracted and estimated
in the leaves of seedlings at 10, 20 and 30 DAS stages.

11. iv. Observations to be recorded: Activities and specific
activities of antioxidant enzymes will be recorded.
Contents of H2O2, malondialdehyde, ascorbic acid, total
phenols and proline will be recorded.
v. Statistical analysis: Results will be analyzed by applying
Duncan’s multiple range test (DMRT) at 0.05% level of
significance.

12. EXPERIMENT NO : 3
i. Name of the experiment: Effect of hydro- and hormonal
priming on grain yield of spring maize under low
temperature stress.
ii. Location of work: Department of Biochemistry and
Department of Plant Breeding and Genetics, Punjab
Agricultural University, Ludhiana.
iii. Methodology: Maize seeds will be sown as described in
Experiment No.1 and grain yield will be determined.
iv. Observations to be recorded: Grain yield will be recorded
at maturity.
v. Statistical analysis: Results will be analyzed by applying
Duncan’s multiple range test (DMRT) at 0.05% level of
significance.

13. S.
No.
Name Designation and Department
1.
Dr. Kamaljit Kaur
(Major Advisor)
Assistant Biochemist
(Department of Biochemistry)
2.
Dr. Vikramjit Kaur
Zhawar
Assistant Biochemist
(Department of Biochemistry)
3. Dr.Yogesh Vikal
Senior Geneticist
(School of Agricultural Biotechnology)
4.
Dr. Dharampal
Choudhary
(Nominee of Dean
PGS)
Principle Scientist (Biochemistry)
(Indian Institute of Maize Research-ICAR)
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