I In of

Ann. Bangladesh Agnc. 2Q)

:

123-125, 1992

CHLOROPHYLL DETERMINATION IN MT

GENBRATION OF RICE A Bhowmik and M. D. Hossain

Department of Genetics and Plant Breeding Institute of Postgraduate Studies in Agriculture

Salna, Gazipur-l 703, B angladesh Abstract

The chlorophyll content of rice

^leaves

was

determined

in Ml

generation

from green flag

leaves.

The Ml

population

was

^developed

by treating the fertilized egg cells using MNU (N-methyl-

N nitrosourea).

The

chlorophyll

a and b

were higher

in the M1

population

than the

^control.

The

correlation betrveen mean green

leaf weight

and chlorophyll

a and b

was moderately

high. The

correlation between the chlorophyll a and b was very high.

Key words.' Rice, Chlorophyll, Leaf weight.

The chlorophyll a and b play an important role in the meabolic activities of the plant and

finally

to the yield. Chlorophylls are ttre major

light absorbiirg pigments of the

^plants

(rhninger,

1982). The chlorophyll content

of

rice leaves varies

within

the species and types

(Yamaguchi, 1942 and Nagai, 1959).

^The chlorophyll a and

b

contribute directly

to

the total chlorophyll, but their order of distribution

is not clear (Choudhury,

^1972).

Very

few reports are available

on

the variation and lhe correlation of chlorophyll a and b with the green leaf weight in rice.

The present study was

undertaken to investigate the variation and interrelationship

of

chlorophyll a, b and total with green leaf weight in the M1 generation.

The fertiliz"d egg cells of BR2 were reated

after

about

6 (six)

hours

of fertilization

by

dipping the

^panicles

into lmM solution of

MNU(

N-Methyl-N-nitrosourea). The panicles

only' with fresh fertilized spikelets

were immersed into

MNU

solution for 45 minutes at about 24oC under dark condition. The plants were treated

at 2 hour

interval

from the lst

treatment

started at 6.00 p.m. In total

8 treatments have been given

to

the plants. The panicles

of the

treated

plants were

washed immediately after the treatment was over for 24 hours in running water.

The M1

populations

were

planted along wittr control in a completely Randomized Block Design with ttrree replications at the Institute

of

Postgraduate Studies

in Agriculture,

Gazipur farm during Aus season, 1989.

Chlorophyll was determined from the fresh flag leaves. The total leaf weight was taken in grammes.

The leaf

was then

cut into

small pieces

and pestled with

absolute methanol (Celowlek _and Kaplan,1957). The extract was

I

t24

then

filtered

and calibrated

upto 50 ml

with methanol. Tfre process was repeated thrice

for each sample. Chlorophyll a and b

^were

determined

on weight basis according

to Mackinnay (1941) using a Spectrophotometerof model 2ffi-24-Hiachi.

The

mean

green leaf weight varied from 0.1825 g to 0.3756 g (Table 1). The highest leaf weight was observed

in

the control. Treatment number

VIII

showed

the lowest

green leaf weight. The mean chlorophyll a content varied

from 2.8474 to 6.6321 mglg. The

highest

chlorophyll a was found in

^treatment

VI

followed by Treatment

VII.

Control showed the lowest chlorophyll a content. Chlorophyll b also

showed a

considerable

range of

^variation

(0.1520

to

^1.8359

mg/ g). The

highest was observed

in teatment Vl

and

the

lowest in

control.

Choudhury (1970) reported ttrat the

range of chlorophyll a varied more

than

chlorophyll b. Bhowmik and

Choudhury (1984) also reported

a

considerable range

of

variation in chlorophyll a and b.

The interrelationship between chlorophyll

a,

b

and green leaf weight was studied

to

find out the relationship among them.

The correlation between chlorophyll a and

b was very high (Frg. 1) The

correlation between mean green leaf weight and chlorophyll

a

and

b

was determinbd

without

considering

control since it

showed

a wide range of

deviation

from

mean green leaf weight

of

the treated populations.

The

correlation between green leaf weight and chlorophyll a and b was moderately

high. Bhowmik and

Choudhury (1984) reported that there was

no

correlation between mean green leaf weightandchlorophyll

a and b.

Figure I

showed

the linear

regression among chlorophyll a, chlorophyll

b

and green

leaf weight. The figure

showed

a

moderate range

of disribution of the points from

the regression line.

From the results

it

can be concluded that a moderate range

of

variation was observed

for

chlorophyll a, b and the green leaf weight. The

chlorophyll a and b were higher in

the

M1 population than the control.

Table

I.

Mean green leaf weight and the chlorophyll content in rice leaves.

Source Mean green Chlorophyll a Chlorophyll b

leafweiqht

⁽

Conmol

Trearnent I Treaunent tr Treatment m Treatrnent IV Treafinent V Treament VI Treatment Vtr

Treatment

VIII

0.3756 0.2350 0.2438 0.2197 0.2183

0.zbr

0.2479 0.2525 0.1865

2.8474 4.9995 5.2735 4.8963 4.5449 4.4095 6.6321 5.4047 3.1668

0.1520 0.9338 0.9016 0.7311 0.7122 r.0299 1.8359 r.0924 0.2905

I ₌ 0.964 Y =-1.02 +0.40 ^X

1.5

1.2

!t E.b

E ^0.0

E 0.[

l:l

; ,,1

*j

125

r ₌ 07'11

Y : -2.6 + 13.?1 x

Lehninger, A. L. 1987.

Principles

Biochemistry. CBS

Publishers Distributors, India. pp. 653.

Mackinnay,

A. 194L

Absorption

of light

by

chlorophyll solution. J,

^Biol.

Chemisrry. 140: 315.

Nagai,

I.

1959. Japonica Rice, its Breeding and Culture. Yokendo Ltd. Tokyo.

Yamaguchi,E. 1942. On the difference

of

the chlorophyll contents

of

the leaves

of

rice plants.

J.

Soc. Trop.

Agric.

14 :

52-59.

0.10 0.19 0.20 0.21 ,

gn

0.23

0.2f

O.E

Ctrrtr tcaf rclht

Fig, 1.

Correlation benveen chlorophyll a and chlorophyll b; chlorophyll a and green leaf weight;

and chlorophyll b and green leaf weight.

Reference

Bhowmik, A.

and

M. A. Choudhury.

^1984.

Chlorophyll

content

in rice

crosses.

Bangladesh

J. Agril.

Res. 9(2)

:119

- 123.

Celowlek, S. P. and N.O. Kaplan.

1957.

Methods

of

Enzymology :.

Vol. VI.

Academic Press. New

York. pp.342-

343.

Choudhury, M. A. 1970.

Chorophyll determination

in

three

rice

crosses.

Action.8(2) :

rc-n.

Gmen tcil ueight

of

and