Effect of Salinity Stress on the Vegetative Growth of Radish (Raphanus sativus L.)

1. MASTER OF PHILOSOPHY
IN
BOTANY
UNDER THE SUPERVISION OF PRESENTED BY
DR. R.K.AGNIHOTRI ANURADHA
DEPARTMENT OF BOTANY
SCHOOL OF LIFE SCIENCES,
KHANDARI CAMPUS, DR. B. R. AMBEDKAR UNIVERSITY
AGRA-282002
Effect of Salinity Stress on the Vegetative
Growth of Radish (Raphanus sativus L.)

2. RADISH (Raphanus sativus L.)
Classification:
Kingdom - Plantae
Division - Magnoliophyta
Class - Magnoliopsida
Order - Brassicales
Family - Brassicaceae
Genus - Raphanus
Species - sativus

3. INTRODUCTION
The word radish originated from Latin word Radiix which means “Root” and
Greek word “Raphanus” which translates to “quickly appearing”.
Radish is a winter season vegetable crop. The radish is sown in winter season,
during September to January in northern plains.
Radish (Raphanus sativus L.) is a popular and common root vegetable, which is
grown in all over the world especially in temperate and tropical region.
Radish is a good source of vitamin B complex (B1, B2, B3, and B6and B9) and C
(ascorbic acid), Folic acid and minerals (Calcium, Iron, Magnesium, Manganese,
Zinc, Potassium and Phosphorus) and also contains carbohydrate, sugars, fibers,
Protein, some fat and fluorides.
The leaves of radish are good source for extraction of protein on a commercial
scale and seeds are source of non-drying fatty oil. The oil is used in soap making.
 The radish plants are affected by the various abiotic factors like drought, heat,
temperature, heavy metals and salinity.
These stresses cause the dehydration in plants, which result the less amount of
water is absorbed by plant cells.

4. Salinity
Salinity is a concern when an “excessive” amount of soluble salts
occurs present in the salt, as a result of mismanaged irrigation water.
Types of Salinity:
The soil salinity is classified into two types:
Sodic soil (ii) Saline soil
The main difference between both of two types of salt affected soil is
the nature of anion and pH of soil.
Sodic Soil: Carbonate and bicarbonate ions are present in this type of
soil with pH of more than 8.5.
Saline Soil: Chloride and sulphate ions are found in the saline soil
with pH having less than 8.5.

5. Effect of salinity on plants
Salt treatment significantly declined shoot and root fresh and dry weight,
emergence percent, leaf number per plant, leaf relative water content,
chlorophyll and mineral content, but increased electrolyte leakage.
The salinity decreased germination percentage and also delayed the
germination rate as salt level increased.
 Lengths and fresh weights of root and shoot decreased with the increasing of
salt concentration.
Soil salinity affects seed germination by decreasing the osmotic potential and
toxicity of specific ions such as sodium (Na+) and chlorine (Cl¯), as well as
decreasing essential nutrients such as calcium and potassium.
Increasing sodium ions at the root surface disrupt plant potassium nutrition.
Because of the similar chemical nature of sodium and potassium ions, sodium
has a strong inhibitory effect on potassium is taken by the root.
Salinity reduces the ability of plants to take, up water, leading to metabolic
effect that reduces plant growth.

6. Objectives
To study the effect of NaCl on seed germination and vegetative
growth of two varieties of radish, i.e. MAHY 22 and TOKITA
WHITE.
To study some physiological parameter (root and shoot length,
fresh and dry weight of root and shoot, root development and leaf
area) of salt treated plants.
To determine the some biochemical parameter (estimation of
chlorophyll and proline content) of salt (NaCl) treated plants.
To compare all the physiological and biochemical parameters
between two varieties of radish (Raphanus sativus L.) of each
concentration.

7. Materials And Methods
The following two experiments have been carried out simultaneously –
Petridish experiment:
To study the effect of salt on seed germination and physiological parameters.
Pot and sand culture experiment:
To see effect of Co and Pb on growth, physiology and biochemistry.
ASSAY AND DETERMINATION
1. Physiological Parameters
a) Germination percentage
(b) Seedling growth
(c) Root development
(d) Biomass production
(e) Leaf area

8. 2. Biochemical parameters
Total chlorophyll estimation
For estimation of chlorophyll in leaves, Brougham (1960)
method was adopted
 
w1000
v663)(OD8.02645)(OD20.2
fWgmgChl.total 1-



Proline content
For the detection of proline in leaves Bates et al., (1973)
method was followed.

9. Results
Fig 1 : Effect of salt on germination % of radish (Raphanus
sativus) grown in laboratory

10. Germination in field
Fig 1 : Effect of salt on germination % of radish
(Raphanus sativus) grown in field