Seed morphometric studies of some Kenaf (Hibiscus canabinus) accessions

ABSTRACT: Fifteen kenaf lines collected from kenaf and Jute Improvement Programme of Institute of Agricultural Research and Training (I.A.R.& T.) were subjected to digital imaging analysis using USB microscope with digital imaging software (Veho™ UK) and Vernier caliper to study the seed morphometric of available kenaf accession and the possibility of using the morphometric data to determine variations between the accessions. Ten seeds in four replicates of each seed lot were randomly selected and measurement of the seed length, seed width, seed angle and seed thickness were taken. The measurements were inputted and saved into Microsoft excel from where the mean value of each parameters were calculated for each replicates. Data were subjected to Analysis of variance, correlation analysis, principal component analysis and clustering analysis. Variation exit among seed of kenaf accessions though they had similar microscopic appearance features. Seed area, which was a function of seed length and seed width contributed largely to the variation that exist between the seed of kenaf accessions. Accession HC-583-312, clearly distinguished itself from others and therefore can be used in parent selection during breeding programmes. The inclusion of this seed morphometrics trait in taxonomic description of kenaf is recommended to increase the accuracy of morphological classification of kenaf.

029-033 | JRA | 2012 | Vol 1 | No 1

This article is governed by the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which gives permission for unrestricted use, non-commercial, distribution and reproduction in all medium, provided the original work is properly cited.

www.jagri.info

Journal of Research in

Agriculture An International Scientific

Research Journal

Authors:

Adetumbi JA1,

Adekoya MA1,

Adeyeye OO1 and

Ogunbiyi B2.

Institution:

1. Institute of Agricultural

Research and Training,

Obafemi Awolowo

University, P.M.B.5029,

Moor Plantation. Ibadan

Nigeria.

2. Federal College of

Agriculture, P.M.B.5029,

Moor Plantation, Ibadan.

Corresponding author:

Adetumbi JA

Email:

jaadetumbi@yahoo.com.

Web Address:

http://www.jagri.info

documents/AG0008.pdf.

Dates: Received: 20 Nov 2011 Accepted: 13 Dec 2011 Published: 25 Jan 2012

Article Citation: Adetumbi JA, Adekoya MA, Adeyeye OO and Ogunbiyi B. Seed morphometric studies of some Kenaf (Hibiscus canabinus) accessions. Journal of Research in Agriculture (2012) 1: 029-033

Original Research

Journal of Research in Agriculture

Jou

rn

al of R

esearch

in

A

gricu

ltu

re

An International Scientific Research Journal

INTRODUCTION

Cultivar identification for the attainment of

Plant Breeding Rights (PBR) requires taxonomic

and genetic approach to determine cultivar

distinctness. The most common methods used for

varietal identification are morphological

characterization which are often time consuming,

expensive, influenced by environment and therefore

lack precision. Morphometric variation has been

widely used in determining potential plant diversity

at the visible level in the sea grass Halodule

wrightii (Creed, 1997). Wyllie-echeverria et al.,

(2003) have also proved that metric measurements

on seeds can be very important in quantitative

variables for determining size and shape of seeds.

Kenaf is a member of the hibiscus family (Hibiscus

cannabinus.L) related to cotton and okra. It is an

annual or biennial herbaceous plant growing to 1.5

– 3.5m tall with a woody base. Kenaf are used by

small pulp mills primarily in countries like China,

India and Thailand. (Dempsey 1975). In Nigeria,

main uses of kenaf fibre are producing rope, twines,

coarse cloth (similar to that made from jute), and

paper. Other uses of kenaf fibre include engineered

wood insulation, various types of environmental

mats, packing materials and material that absorbs

oil and liquids. (Mabberly, 1987) Many varieties of

kenaf are often mentioned in literature based on

their performance in one character or the other but

concise varietal identification of kenaf is always

problematic and knowledge on genetic diversity of

kenaf varieties is limited. Since all forms of

breeder’s protection require some measure of

distinctness, cultivars identification is therefore a

pre- requisite for the effective provision of Plant

Breeding Rights (PBR). It is based on these facts

that this experiment set to study the seed

morphometric of available kenaf accession and the

possibility of using the morphometric data to

determine variations between the accessions.

MATERIALS AND METHODS:

Clean seed of fifteen kenaf lines (Table 1)

were collected from kenaf and Jute Improvement

Programme of Institute of Agricultural Research

and Training (I.A.R. & T). Ten seeds in four

replicates were randomly selected from each seed

lot of the 15 accessions, thereafter, each of the ten

seed samples were subjected to digital imaging by

placing each seed sample under the USB

microscope in such a way that the flat embryo axis

of the seed was facing the lens of the camera under

light and 40X magnification. The light and

magnification focus adjuster on the USB

microscope was adjusted until desired brightness

and magnification that gives clear image. The

seeds were then viewed on computer system before

the image of the seed was captured. The captured

image was then double clicked to be previewed and

displayed at the measurement window of the USB

microscope. At the display of the seed image,

magnification at which the seed image was captured

was inputted; thereafter measuring tools were used

to take various precise measurements of the features

on the seed in millimeters. Measurements taken

were:

i. Seed length - This is the greatest dimension on

the seed taken at base of the seed.

ii. Seed width – This is the cross section taken at

right angle to the length of the seed.

iii. Seed angle – This is the angle formed from the

tip of the seed to the base.

iv. Seed area – This is calculated from the seed

length and seed width using the formula: ½

base x heights.

v. Seed thickness was however obtained by

holding each kenaf seed in between the vernier

caliper to digitally measuring the thickness

The values of these parameters taken were

saved in Microsoft excel from where the mean

value of each parameters were obtained for each

replicates. Data collected were subjected to analysis

of variance and correlation analysis using SPSS.

Principal component procedure was used to

estimate the variability among the accessions while

the clustering analysis was used to group the

accessions based on variables with highest variation

based on morpho-metric similarities.

030 Journal of Research in Agriculture (2012) 1: 029-033

Adetumbi et al.,2012

Entry number Accessions

1 Cuba 108

2 Exshika24 4

3 Ifekan 100

4 AU-71-93

5 HC-583-312

6 AU-75- 413

7 V1-100-10 1

8 AC-313-302

9 2QQ-171

10 G45-23

11 AC-313-292

12 PURPLE FLOWER

13 AC-313-244

14 A-60 282-5

15 2QQ-13

Table 1: List of Kenaf Accessions used for

the experiment

RESULTS AND DISCUSSIONS

Variability among metric measurements on

kenaf seed

Mean squares from analysis of variance of

seed morphometrics parameters for fifteen kenaf

lines revealed significant differences at P<0.05 in

all the parameters except seed angle (Table 2).

From the result, it is clear that variation exist

among the seeds of fifteen kenaf accessions with

respect to some of the characters evaluated. This

indicates that descriptors of seed differences can be

effectively exploited in physiological studies as

stated by Dell’ Aquila (2004), and in cultivar and

genotype description.

Mean values of the morphometric measurements

of kenaf seed.

Mean morphometric data of fifteen kenaf

accessions are presented in Table 3. 2QQ-13 had

the longest seed length (5.42 mm). The shortest

seed length is recorded for HC-583-312 (4.15mm)

was significantly different from other accessions at

P<0.05. Similarly, HC-583-312 recorded the

shortest seed width (3.23mm) and seed area

(6.72mm), which were also significantly different

from other accessions. Thickness of Ex-Shika 24-4

recorded the highest value (2.51mm) which was not

significantly different from another eight

accessions. Also, Purple flower accession had the

lowest thickness value (2.03mm), which was not

significantly different from AU2452-4A. There was

no significant difference in the seed angle of almost

all the accessions. Cuba 108 recorded the highest

seed angle (75.66 mm) which was not significantly

different from the value recorded for AU-75-413

(75.60mm) while AC-313-302 recorded

significantly lowest seed angle (69.81mm).

Intercharacter relationship among kenaf seed

Correlation coefficients among the

mormhometric data of the fifteen kenaf accessions

shows that seed width significantly and positively

correlated with seed length and seed area (r =

0.0738 and r = 0.0939 respectively).Table 4). Also

significant positive correlation exist between Seed

length and seed area (r =. 0.039). Though the

correlation between seed thickness with both seed

width and seed length are positive, they are not

significant at P<0.05. Seed angle is negatively

correlated with seed width and seed thickness and

they are not significant.

Journal of Research in Agriculture (2012) 1: 029-033 031

Adetumbi et al.,2012

Sv Df Seed length Seed width Seed thickness Seed angle Seed area

Accessions 14 0.40* 0.23* 0.06* 11.23 5.10*

Error 45 0.04 0.04 0.02 8.63 0.53

Total 59

Table 2: Mean square values for kenaf seed morphometrics.

Accessions Seed length Seed width Seed thickness Seed area Seed angle

Cuba 108 5.00bcdef 3.61cde 2.33abc 9.02def 75.66a

Exshika24 4 5.22abc 3.80abc 2.51a 9.97abcd 71.50ab

Ifeken 100 4.94cdef 3.61cde 2.39ab 8.90def 71.84ab

AU-71-93 5.15abcd 4.02ab 2,41ab 10.36abc 72.37ab

HC-583-312 4.15g 3.23f 2.29bcd 6.72g 71.50ab

AU2452 4A 4.70f 3.40ef 2.11de 7.80f 73.34ab

V1-100-10 1 4.72ef 3.46def 2.35ab 8.17ef 73.55ab

AC-313-302 5.18abcd 3.94abc 2.32abcd 10.19abc 69.89b

2QQ171 5.03bcdef 3.78abcd 2.27bcd 9.49bcd 71.99ab

G4523 4.80ef 3.70bcd 2.37ab 8.87def 70.99ab

CUBA OVATE 671 5.04bcde 3.66cde 2.28bcd 9.22cde 72.98ab

PURPLE FLOWER 4.88def 3.62cde 2.03e 8.81def 71.46ab

AC-313-244 5.28ab 4.00ab 2.32abcd 10.57ab 72.78ab

A-60 282-5 5.31ab 4.06a 2.34abc 10.79a 74.69ab

2QQ-13 5.42a 3.85abc 2.13cde 10.45ab 75.60a

Table 3: Means of Kenaf seed morphometrics

Mean followed by the same alphabet within the same column are not significantly different from each other.

The positive and significant correlation that

exists between seed width and the other two

characters (seed length and seed area) indicates that

improving on any of the parameter will

significantly increase other characters. Also, since

they are significantly correlated, each can be used

as substitute in any evaluation and classification

studies and as such these characters possessed

greater practical value for seed discrimination in

kenaf. Wyllie-echeverria et al. (2003) did show that

seed size and seed metrics were important

discriminators of Zostera marina. Similar result

was obtained on Jathropa by Kaushik et al.,(2007).

Seed angle had negative and non significant

relationship with seed width and seed thickness.

This denotes that as the width of the seed increases,

the angle reduces or improvement on the seed width

or thickness will significantly reduce the seed

angle, although the effect might not be significant.

Factors contributing to variations among kenaf

seeds

The result of the principal component

analysis showing the Eigen values and percentage

contribution are presented in Table 5. Principal

component 1 and 2 are of major importance. The

result shows that PC 1 and PC 2 accounted for

59.80% and 24.51% variance respectively.

Principal Component 1 was loaded largely by seed

area (0.994) indicating that seed area contributes the

largest variability while seed angle contributes the

least variability (0.229). However, with PC 2, seed

angle (0.799) contributes the largest variability

while seed width (-0.119) contributes the least

variability. The eigen values of the two principal

component are more than one.

The output of the principal component

analysis shows that different characters contributed

differently to the total variation as indicated by their

eigen values as well as loading on different

principal axis. Seed area contributed largely to the

variation that exists in PC 1 because the seed area is

the function of other two variables (seed length and

seed width). However, in PC 2, seed angle

contributed the largest to the variation that exist

between the accessions because the seed angle is

independent of other parameters

Degree of relationship among kenaf accessions

based on seed metrics

The result in Figure 1 shows the dendogram

032 Journal of Research in Agriculture (2012) 1: 029-033

Adetumbi et al.,2012

Table 4: Correlation coefficients of observed kenaf

seed mormphometrics

Seed

width Seed

length

Seed

thickness Seed

angle Seed

area

Seed width

1 0.738* 0.148* -0.102 0.939*

Seed length

1 0.104 0.244 0.923*

Seed thickness

1 -0.072 0.145

Seed

angle 1 0.069

Seed

area 1

Character PC 1 PC 2

Seed width 0.965 -0.119

Seed length 0.969 0.142

Seed thickness 0.284 -0.743

Seed angle 0.229 0.799

Seed area 0.984 0.005

Eigen value 2.99 1.23

% variance 59.79 24.51

Table 5: Principal Component analysis showing the

eigen value and percentage contributions of each

variable. Case 1 Cuba 108 Case 9 2QQ171

Case 2 Exshika24 4 Case 10 G4523

Case 3 Ifekan 100 Case 11 CUBA OVATE

671

Case 4 AU-71-93 Case 12 PURPLE

FLOWER

Case 5 HC-583-312 Case 13 AC-313-244

Case 6 AU2452 4A Case 14 A-60 282-5

Case 7 V1-100-10 1 Case 15 2QQ-13

Case 8 AC-313-302

Legend:

Figure 1: Dendogram showing the morphometric

similarity among fifteen kenaf accessions

Cluster Tree

from single linkage cluster analysis (SCLA) of the

fifteen Kenaf accessions. At a minimum distance of

0.00 level of similarity, all the accessions were

distinct from each other while at a distance of 1.00

level of similarity, only accession five (HC-583-

312) can be distinguished from other accessions that

formed into a cluster.. However, at 0.68 level of

similarity, accessions Cuba 108(1), 2QQ-13(15) and

A-60-282-5(14) were similar to one another but

clearly distinct from other accessions.

The dendogram generated from similarity

and distance matrices provided an overall pattern of

variation as well as degree of relationship among

the accessions. The result from this study has

provided two major clusters at the 1.00 level of

similarity, with fourteen out of the fifteen

accessions forming a cluster. This indicates that

only one accession (HC-583-312) has distinct

features that can be used to distinguish it from

others. However, at a lesser level of similarity

(0.68), three clusters can be identified. It is

therefore clearly shown from this study that seed

morphometrics of kenaf could not provide

convincing discriminatory evidence in the

classification of kenaf genotypes.

CONCLUSION

This experiment has shown that this imaging

technique can be applied to the identification of

seeds and it has shown that seed of kenaf varieties

had similar microscopic appearance features. The

seed morphology of the kenaf varieties however

proved that there are differences in their length,

width and thickness. However, this distinction

cannot be used as a tool to identify kenaf varieties.

REFERENCES:

Creed JC. 1997. Morphological variation in the

seagrass Halodule wrightii near its southern

distributional limit. Aquat. Bot., 59:163-172.

Dell’Aquila A. 2004. Cabbage, lentil, pepper and

tomato seed germination monitored by an image

analysis system. Seed Science and Technology

32:225-229.

Dempsey JM. 1975. Fibre crop. Univ of Florida

Press.

Kaushik N, Kumar K, Kumar S, Kaushik N, and

Roy S. 2007. Genetic variability and divergence

studies in seed traits and oil content of Jatropha

(Jatropha curcas) accessions. Biomass and

Bioenergy 31:497-502.

Mabberly DJ. 1987. The Plant book. A portable

dictionary of higher plants. Cambridge University

press. Cambridge 706, ISBN 0-521-340-60-8.

Wyllie-Echeverria S, Coxfls PA, Chuchill AC,

Brotherson JD, and Wyllie-Echeverria T. 2003. Seed size variation within Zostera marina L.

(Zosteraceae). Bot. J. Linn. Soc., 142:281-288.

Journal of Research in Agriculture (2012) 1: 029-033 033

Adetumbi et al.,2012

Submit your articles online at www.jagri.info

Advantages

Easy online submission Complete Peer review Affordable Charges Quick processing Extensive indexing You retain your copyright

submit@jagri.info

www.jagri.info/Sumit.php.