Research Journal of Agricultural Sciences 2011, 2(2): 213-216

Prediction of Storability of Different Seed Size Grades of French bean Varieties through Accelerated Ageing Response

K Vishwanath, Pallavi H M, Devraju P J and Prashanth Y Department of Seed Science and Technology,

University of Agricultural Sciences, GKVK, Bangalore - 65, Karnataka, India e-mail: vishwakoti@gmail.com

A B S T R A C T Seeds of French bean varieties Arka komal and Burpee stringless were size graded viz Bulk, 4.50mm, 4.75mm and 5.00mm and these grades were aged artificially to evaluate for seed quality after ageing. Seeds of bigger size (5.00mm) showed significantly better seed quality parameters in terms germination, seedling length, seedling vigour index and enzyme activity (dehydrogenase and α- amylase) followed by 4.75mm and 4.50mm and were lowest in bulk seeds in both the varieties. Highest electrical conductivity was noticed in small seeds than bigger seeds. However pH did not vary between size grades. Among varieties Burpee stringless showed better seed quality than Arka komal and these results suggesting superiority of bigger seeds.

Key words: French bean, Storability, Ageing response, Arka komal, Burpee stringless

Seed vigour is component of seed quality along

with viability, health, structural soundness and seed

size. Among these, seed size also is an important

component as it influences the performance, vigour and

storability of seeds. The influence of seed size on

seedling vigour, crop productivity and storability has

drawn attention of researchers since long time (Dhillon

and Kler 1976). It is opinion of several workers that

plump seeds can be stored for long period (Anonymous

1998, Gontia and Awasthi 1999, Dhillon and Kler 1976.

Khare and Satpute 1999) and contradictory results by some researchers (Dhillon and Kler 1976, Khare and

Satpute 1999). Proper selection of seed size is essential

to achieve better seed quality and long period

storability. Information on storability of French bean

seed to preserve viability and vigour from harvest to

next planting season and carry over or transport purpose

is prime importance in any successful seed production

programme, therefore study was undertaken to evaluate

the seed size influence on seed quality after accelerated

ageing in French bean varieties.

MATERIALS AND METHODS Seed of two French bean varieties Arka komal and

Burpee stringless were size graded by using different

screen sizes viz 4.50, 4.75 and 5.00mm and bulk seeds

were taken as control. 100 seeds from each grade in

eight replications were weighed and recorded mean test

weight for each size. Before accelerated ageing

germination of seed were recorded by using standard

germination test (ISTA 1996). Seeds from each size

grades were subjected to accelerated ageing in an

ageing chamber where temperature of 40°C and 100 per

cent relative humidity was maintained for three days

(72h) (Delouche 1965). At end of ageing period the

samples were removed and dried back to original

moisture content under shade and were set out for

germination test using between paper method with 400

seeds in four replications. The ageing response was

measured based on normal seedling as germination after

accelerated ageing (GAA) (ISTA 1996).

After germination count, 10 randomly selected

seedlings were measured for seedling length and same

seedlings were dried in hot air oven at 85±5°C for period of 8h and seedling dry weight was recorded.

Seedling vigour index was computed as a product of

germination percentage and seedling length. (Abdul-

Baki and Anderson 1973).

50 grams of clean seed was soaked in 100 ml of

distilled water in three replication for 24h at ambient

condition. The supernatant was collected and electrical

conductivity (EC) of seed leachate was measured using

conductivity bridge, EC of distilled water was taken as

control and expressed in dsm-1.

40 seeds were randomly selected from each grade and pre conditioned the seeds by soaking seeds for

overnight. Seed coat was removed then sit it for

tetrozolium staining (0.05%), 10 seeds in each

replication. Farmazon was eluted in screw-capped vials

by using 20ml of methoxy ethonol and OD values were

red at 480nm wavelength using spectrophotometer.

The α-amylase activity was estimated semi

quantitatively by adapting Bed Rock Model. The pre

imbibed seeds were cut in to two halves, halve with

embryo intact was placed equidistantly on to a sterilized

petriplates containing 2% starch agar media in such a

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way that embryo portion of seed should come in contact

with agar and incubated for 24h at 25±5°C. Then the

seeds were removed and iodine solution was poured on

to the starch medium. After 30 minutes, the observation

on clear halo zone diameter (cm) formed indicating α-

amylase activity was measured. Data collected were statistically analyzed by the

analysis of variance techniques by adopting following

completely randomized design (CRD) (Panse and

Sukhatme 1967). Arcsine square root method was

applied for transformation of data, which was applied

on those tables in which the values were less than ten or

in percentage.

RESULTS AND DISCUSSION 100 seed weight increased gradually as seed size

increased from bulk seed (33.54g) to 5.00 mm (39.83g).

Among varieties Burpee Stringless showed higher test

weight (38.93g) than Arka Komal (33.78g). The

varieties used in this experiment showed good

germination before accelerated ageing i e 92.08 and 93.50 per cent in Arka komal and Burpee Stringless,

respectively. Among seed sizes, bulk seed showed

lowest germination (90.54%) and was in increasing

trend as increase in size from 4.50 mm (92.11%) to 5.00

mm (95.44%).

Table 3 Seed enzymes activity as influence by seed size after accelerated ageing in French bean varieties

Seed size (S) Total Dehydrogenase (OD value) Amylase (Halo-zone diameter (mm))

V1 V2 Mean V1 V2 Mean

Bulk seed 20.2 18.3 19.25 2.6 2.7 2.8

4.50mm 22.0 25.5 23.7 3.1 2.9 3.0

4.75mm 25.1 28.7 26.9 3.2 3.0 3.1 5.00mm 31.5 28.8 30.1 3.2 3.4 3.3

Mean 24.7 25.3 24.9 3.0 3.2 3.1

S. Em± CD (0.05P) S. Em± CD (0.05P)

Seed size (S) 0.68 2.00 0.082 0.24

Varieties (V) 0.50 1.41 0.060 0.17

S × V 1.00 2.83 0.12 0.35

Germination after accelerated ageing (GAA) was

gradually increased with increase in seed size from 4.50

mm (74.79%) to 5.00 mm (84.08%) and it was lowest in

bulk seeds (68.12%). Higher germination after

accelerated ageing in large seeds compared to small seeds also noticed by several researchers (Duode 1984,

Malarkodi et al.1998). Higher GAA in large seeds

might be due to higher storage food reserves and higher

enzyme activity (Table 2). The influence of seed size

also evident by the more loss of germination after

accelerated ageing in bulk and small (4.50mm) seeds, in

other words least loss in 4.75 and 5.00mm seed,

respectively. The net loss of germination for bulk seed

was 24.7 per, 4.50 mm was18.8 per cent, while it was

16.2 and 11.9 per cent in 4.75 and 5.00mm size seeds.

The variety Burpee Stringless recorded higher GAA (77.89%) then Arka komal irrespective of seed sizes.

Lower GAA in Arka komal is due to higher mycoflora

load (recorded) and its lower test weight resulted in

faster degradation of food reserves their by lower

amount of food reserves available for mobilization and

such varietal differences for germination after storage

was observed by earlier researchers. Increase in GAA in

Arka komal with increase in screen size from 4.5mm

(65.58%) to 5.00mm (83.41%) accounts for 6.92 and

17.83 per cent increased GAA, respectively over

ungraded seeds (65.58%). Seed retained on 4.75mm

screen size recorded 84.00 per cent germination which was 11.08 per cent higher GAA over ungraded seeds. In

case of Burpee stringless 4.5 mm (77.68%), 4.75mm

(79.08%) and 5.00mm (84.75%) screen sizes vary

among each other for GAA which had 6.42, 8.42 and

14.09 per cent increased GAA over ungraded seeds

(70.66%). Better GAA in large seed might be due to

higher enzyme activity which is require for food

reserves mobilization and higher food reserves even few of that degraded during ageing process and remaining

huge amount for plume and radical growth by higher

enzymatic biosynthesis. Several researchers have

observed higher GAA in bigger seeds than smaller

seeds (Malarkodi et al.1998).

Seedling length, seedling dry weight and vigour

index were increased with increse in seed size from

4.50 to 5.00mm and these parameters are least in

ungraded seeds. In case of Arka komal seedling length,

seedling dry weight and vigour index were increased

with increase in seed size from 4.50 to 5.00mm and lowest in ungraded seeds. In Burpee Stringless all

aforesaid quality parameters vary distinctly among

seeds retained on 4.50, 4.75, 5.00mm and bulk seeds.

Reduced quality attributes after accelerated in Arka

Komal was mainly due to higher seed mycoflora lode

(recorded) and lower test weight and lower food

reserves, which are mobilized during germination (Bhor

et al.1988).

Electrical conductivity was highest in bulk seeds

(1056) followed by 4.50mm (965) and was reduced to

798 as increase in seed size to 5.00mm. However it was

not vary distinctly between varieties. pH of seed lechate also did not vary much between seed size and varieties.

Enzymes activity viz dehydrogenase and α-amylase

increased with increase in seed size.

Vishwanath et al.

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Table 1 Seed quality parameters as influence by seed size after accelerated ageing in French bean varieties

Seed size (S) 100 seed weight (g) Germination (%) GAA (%) Seedling length (cm)

V1 V2 Mean V1 V2 Mean V1 V2 Mean V1 V2 Mean

Bulk seed 29.55 37.52 33.54 89.75 91.33 90.54 65.58 70.66 68.12 16.08 18.19 17.13

4.50mm 32.00 38.34 35.17 91.66 92.56 92.11 72.50 77.08 74.79 17.03 18.93 17.98

4.75mm 34.56 39.24 36.90 92.83 93.25 93.04 76.66 79.08 77.89 17.82 19.90 18.86

5.00mm 39.01 40.65 39.83 96.80 94.08 95.44 83.41 84.75 84.04 19.03 20.96 19.99

Mean 33.78 38.93 36.36 92.08 93.50 92.73 74.54 77.89 76.21 17.49 19.49 18.49

S.Em± CD (0.05P) S.Em± CD (0.05P) S.Em± CD (0.05P) S.Em± CD (0.05P)

Seed size (S) 0.44 1.28 0.75 2.25 0.30 0.90 2.20 6.22

Varieties (V) 0.30 0.86 0.55 1.50 0.24 0.66 1.56 4.40

S × V 0.62 2.46 1.08 3.00 0.48 NS 3.12 NS

Table 2 Seed quality parameters as influenced by seed size after accelerated ageing in French bean varieties

Seed Size (S) Seedling dry weight (mg) Vigour index Electrical Conductivity (dsm-1) pH

V1 V2 Mean V1 V2 Mean V1 V2 Mean V1 V2 Mean

Bulk seed 107.4 127.2 117.3 1071 1297 1184 1103 1010 1056 6.38 6.31 6.34

4.50mm 107.4 127.2 117.3 1071 1297 1184 1103 1010 1056 6.38 6.31 6.34

4.75mm 115.4 130.5 123.0 1261 1479 1370 969 961 965 6.50 6.57 6.53

5.00mm 126.4 139.8 133.1 1385 1562 1483 916 912 915 6.47 6.40 6.43

Mean 137.3 154.5 145.9 1598 1772 1685 812 798 805 6.27 6.20 6.23

S. Em± CD (0.05P) S. Em± CD (0.05P) S. Em± CD (0.05P) S. Em± CD (0.05P)

Seed Size (S) 2.20 6.22 66 190 2.20 6.22 12.6 36.0 0.44 1.24 12.6 36.0

Varieties (V) 1.56 4.40 46 130 1.56 4.40 9.0 52 0.30 0.86 9.0 52

S × V 3.12 NS 92 260 3.12 NS 18.0 42.1 0.62 2.46 18.0 42.1

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Higher dehydrogenase in large seeds (5.00mm) is

evident by higher OD values and decreased as seed size

decrease from bulk (19.2) to 5.00mm (30.1). Same

trend was also observed in α-amylase activity and

evident by its higher halo zone width (3.3cm) in

5.00mm and lower in bulk seeds (2.8cm). Among varieties Arka komal had lower activity of

dehydrogenase and α- amylase than that of Burpee

stringless. Higher enzyme activity in big seeds is due to

resist of seed to ageing process, in other words small

seed proven to rapid deterioration process resulted in

death of cells and stopping of some hydrolytic enzymes

activity ( Kannababu and Karivartharaju 2001)

In conclusion, large seeds (>5.00 mm) performed

better in all respect of seed quality after accelerated ageing showing its higher vigour and storability. It is

require selecting large seeds for carry over storage in

French bean.

LITERATURE CITED Abdul-Baki A A and Anderson, V D. 1973. Vigour determination in soybean seed by multiple criteria. Crop Science

13: 630-633.

Anonymous. 1998. Recommended sieve sizes for grading of crops, constraints and prospects. Seed Technology

News 28(4): 76-77.

Bhor S B, Thete R Y, Patil R B and Bharud R W. 1988. Effect of seed size on growth, yield, and yield attributes and

seed quality on gram. Seed Research 16(2): 143-147.

Delouche J C. 1965. An accelerated ageing technique for predicting relative storability of Crimson Clover and Falfescne seed lots. Agronomy Abstracts pp40.

Dhillon G S and Kler D S. 1976. Crop production in relation to seed size. Seed Research 4: 143-155.

Douode S D. 1984. Effect of seed size on longevity of seeds in French bean (P. vulgaris). Singapore Journal

Primary Industries 12(1): 62-69.

Gontia A S and Awasthi 1999. Effect of seed grading by size on various seed vigour attributes morphological

characters and seed yield in soybean (Glycine max (L.) Merrill) genotypes. Seed Research 27(1): 25-30.

Kannababu N and Karivaratharaju T V. 2001. Glutamate dehydrogenase activity in seedling organs of sunflower.

Seed Research 29(2): 167-170.

Khare D and Satpute R G. 1999. Influence of days to maturity and seed size on germination and seedling vigour in

pigeonpea. Seed Research 27(2): 170-173.

Malarkodi K, Srimathi P and Parameshwari K. 1998. Influence of size grading on seed quality of yam bean seeds.

Seed Technology News 28(4): 22. Panse V S and Sukhatme P V. 1967. Statistical Methods for Agricultural workers. Indian Council of Agricultural

Research Publication, New Delhi.

Vishwanath et al.

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