Experiment No 2

Effect of high and low salt water on Seed germination

5

Experiment

Material and Chemicals

Overview

Introduction

Procedure

Objective

1

2

3

4

Introduction

Water containing dissolved substances such as chlorides, sulfates, carbonates, and bicarbonates of calcium, magnesium, sodium, and potassium in high concentration is called as high salt water.

Low concentration of dissolved salt will become cause of low salt water.

High and low salt water

Threat of squandering of one third of cultivated land by desertification.

Limited sweet water resources and increase in the use of brackish underground water ,as the main reasons of desertification in Pakistan.

Abiotic stresses for crops Drought light Heat salt stress

Effect of salt concentration on crops

Excess salinity in soil water can decrease plant available water and cause plant stress.

Salt tolerance of plant depends upon its ability to check the movement of salts at five sites.

Selective absorption of roots. Entry of nutrients in xylem.Entry of food materials in the phloem .Exclusion of salts.Evacuation of toxic salts by salt glands.

Effect of high salt water: Wilting of plant

High or low salt concentration become cause of fluctuation in chloride and sodium ions of different parts of plant.

Different critical mechanisms of plant

PhotosynthesisStomatal conductance Transpiration rate

Effects

Salt tolerance and salt sensitivity

Lower conductivity of distilled water than tap water

Types and Causes of Salinity

human-induced salinity

Example of salinity

Experiment for In vitro Seed Germination

Filter paper Tap water NaCl Distilled water Petri dishes Agar HgCl2

Tissue paper Balance Cylinder Beaker

Apparatus and Chemicals

Layout and protocol of the Experiment

Preparation of Agar

Tap ,distilled and salted water is used

Seed Preparation

Soaking of seeds

Agar +Tap water

Autoclave to avoid

contamination

Surface Sterilization of seeds

70% ethanol is used

Laminar flow hood is used

Do not dip into ethanol

overnight

Washing of seeds

Seed coat is removed

Propagation of seed

germination

Transfer of seeds in test Petri dishesAgar+ prepared seeds

orFilter paper +prepared seeds

Provide favorable

conditions for growth

Placement in growth room

And observation of results

Use of Laminar flow hood+ hands should be washed properly

Soak seeds in distilled water, tap water and salted water overnight.

In order to prepare plain agar dissolve 1 gram of agar is in 100 ml of tap water and autoclave it with other necessary apparatus in autoclave at 120c for 20 min.

Take all apparatus in laminar flow to avoid contamination.

For surface sterilization of seeds dip them into ethanol solution for 2-3 minutes.

Protocol

Wash them 2-3 times and then remove seed coats.

Place those soaked and rest of the un soaked seeds in Petri dish with the help of forceps, in which solidified agar media is present.

Place filter paper in Petri dish and pour 5 ml distilled water on it and then place soaked and un soaked seeds on it for germination.

Clover Petri plates with aluminum foil and place them in growth room for a day and check the growth of roots and shoots.

Record observation in form of table daily for one week.

Seeds will germinate more quickly if they are first placed in a cup of tap water and allowed to sit and soak-up water.

Do not dip in HgCl2 overnight.Avoid contamination during experiment.Agar should be fully dissolved in water for media preparation.

Observation

Precautions

Thank You