fungal efect on the planting value of chili seeds

8/8/2019 Fungal Efect on the Planting Value of Chili Seeds

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Efectul fungicelor asupra valorii de plantare a seminţelor de chili

Abstract

Effect of seed borne fungal pathogen on the planting value of chili (Capsicum

frutescens) seeds collected from different sources namely Bangladesh AgricultureDevelopment Corporation , Bangladesh rural advancement committee, Local seed

company, Local seed trader and farmer was studied. Aspergillus flavus, Alternaria

alternata, Colletotrichum dematium, Colletotrichum capsici, Curvularia lunata, Fusariumoxysporum, F moniliforme, Penicillium sp and Rhizopus sp. Were commonly found

prevalent in all the seeds. Aspergillus flavus was recorded highest 11% in BADC chili

seed and Colletotrichum capsici was recorded highest in farmer chili seeds 9%. The

prevalence recorded least in seed company chili seeds next to BRAC seed. Highest prevalence of the pathogen was recorded in seed trader chili seed 34% next to BADC

26% and farmer 23% chili seeds. Germinations and seedling vigour of chili seeds

retained in different sources were affected in different ratios depending on the seed

source,variety, and type of fungal pathogen. The minimum germination of 28.5% in chiliof LSC seeds retained by the farmer was recorded.

Introduction

Chili is an important spice which is grown widely throughout the country. Deenand Basu Chowdhury(1984) detected 22 fungi in chili. Richardson in compiling the

world list of seed borne disease of chili, enlisted 31 seed borne fungi in this corp. Among

the listed fungi, at least 15 were most destructive pathogens to chili. The seed borne prevalence of the fungal pathogen commonly cause seed rot , seed decay, seedling blight,

seed discoloration, germintion failure and germination reduction, seedling damping off,seedling mortality.For successful crop cultivation in Bangladesh, lack of quality seeds is a very

common and usual problem. Seed system in the country is at a very rudimentary stage. A

total of 5 lakh tons of seeds (cereals/vegetables and others crop seeds) per year isrequired , out of which only 5% seeds are produced by different organization with care

but almost regardless of the health status. The rest 95% of these seesd are retained by the

farmers and remain uncertified with unknown quality, and outside the supervision of

seed certification agency.Farmers produce seeds traditionally with no or little care even for purity and

germination remains out of the scope of certification. Consequently, the status of this

seeds remain unsatisfactory and far below the international standards. In this regard, seed production and processing must be followed absolutely by health test and other quality

parameters and a particular vegetable seed should not be certified until its planting value

is justified.Asalmol et al studied fifty chili (Capsicum frutescens) seed samples collected

from Maharashtra, India. They observed that germination was adversely affected by the

presence of seed borne fungi. The present research work was designed to determine the



seed borne fungal pathogens associated with the chili seeds and to evaluate the planting

value of the seeds collected from different sources.

MATERIALS AND METHODS

The experiment was carried out in the Seed Pathology Center of the Department

of Plant Pathology, Bangladesh Agricultural University, Mymensingh, during the periodof March, 2002 to March 2003. Chili seed was selected for the study. Based on the

present market situation the five seed sources were selected for the collection of seed

samples i.e. Bangladesh Agriculture development Corporation , Bangladesh RuralAdvancement Committee, Local Seed Company, Local Seed Trader and Farmer. Each

sample was 100-250g collected from respective sources and preserved in brown paper

bags under Laboratory conditions for subsequent use during the experimental works.

For seed health test, standard blotter method was practiced in the laboratoryfollowing the rules of seed health test recommended by ISTA, 1996. For germination

test- i) Germination in blotter method: A sample at least of 400 seeds is recommended by

ISTA for a statistically germination test . ii) Germination in earthen pot: Germination of

the seeds was also recorded through pot experiment. For this test , earthen pots wereused. Seed vigour was determined by two methods. One is seedling length measurement

method and another is seedling dry weight method.The experiment was laid out in a Completely Randomized Design with four

replications.The data were analyzed by using statistical package program MSTAT-C to

illustrate the statistical significance of the experimental results. He means for all the

treatments were calculated and the analyses of variance for all the components were performed by F-variance test. The significance of differences between the pairs of

treatment means was evaluated by DMRT for interpretation of the result.

RESULTS

The chili seeds collected from different sources were found greatly affected by the

fungal pathogen in blotter.Table 1. Prevalence of seed borne fungal pathogen on chili seeds collected from

different sources.

Colletotrichum capsici and Aspergillus flavus were recorded in all the seeds

collected from different sources. Besides the BRAC seeds were found infected by

Alternaria alternata. Curvularia lunata was observed in BADC, LST & farmer seed. It

was high (9%) in farmer seed and secondly (2%) in LST and BADC seed. Fusariumoxysporum was found associated with vigorous mycelial growth in all sources of seed

except LSC seed and its prevalence was same (4%) to BADC and BRAC seed and 5% in

LST seed which were statistically similar. Penicillium sp was observed in LSC, LST andfarmer seed and its prevalence was 3%, 4% & 1% respectivily. The fungus found to grow

vigorously on the surface of the infected seeds resulting the seed rotten. Rhizopus sp was

observed only in BADC and LST seed and it was 2% which were statistically similar.For germination in blotter, germination percentage of chili seeds collected from

different sources has been presented in the Fig 1. Germination percentage was obtained

from chili seeds and it was highest in farmer (92 %) and BADC (89.5%) seed which were



statistically similar. LST seed showed 60% of germination while BRAC and LSC seed

showed 51.25% and 38.75% respectively.

For germination in earthen pot method , germination procentage of chili has been presented in fig 1. The germination percentage in this pot method decreased

comparatively to the blotter method. Farmer chili seeds yielded highest germination

percentage (89%) when BADC, LST, BRAC and LSC seeds yielded 71.5%, 50% and38% of germination respectively which are statistically different.

In vigour test , the results on seedling length of chili seeds have been presented in

the table 2. In case of chili seeds , seedling length was recorded 10.25 cm in LSC seed &10 cm was recorded in BRAC seeds and 9 cm for other sources seeds which were

statistically similar. Seedling dry matter weight was obtained from different seed sources

and has also been shown in the table 2.

Table 2. Growth rate of chili seeds collected from different sources.

Highest dry matter weight (26 mg) was recorded in BRAC and LSC chili seeds

which were statistically different from all other sources of seeds. However, 21 mg 20 mgdry matter weight were recorded in LST and BADC seeds which were statistically similar

and lowest dry matter weight (17 mg) was recorded in farmer seeds which werestatistically identical to BADC seeds.

DISCUSSION

In chili seeds Aspergillus flavus, Alternaria alternata, Collectotrichum capsici,

Fusarium spp, Curvularia lunata, Penicillium sp and Rhizopussp were observed andidentified. Many other researchers also found these pathogens associated with chili.

Some other seed borne fungi like Cercospora, Cladosporium, Corynospora,

Drechselera , Macrophomina, Phoma , Rhizoctonia etc were observed in chili seeds bymany researchers but in this present study these were not found. Aspergillus flavus was

recorded highest (11%) in BADC chili seed. Asalmol et al. observed the incidence of the

pathogen to be highest (31,42%) on chili seeds in India. Colletotrichum capsici wasrecorded highest in farmer chili seeds (9%) . Alam found highest pathogen (4.5%) in

BADC seeds. Alternaria alternata and Colletotrichum capsici were responsible for seed

rot, seedling mortality, fruit rot and reduction of germination. The pathogenColletotrichum capsici was recorded in BRAC and seed company’s chili seeds.

On the other hand , the prevalence recorded least in seed company chili seeds and

next to BRAC seed. Highest prevalence of the pathogen was recorded in seed trader chili

seed (34%) but next to BADC (26%) and farmer (23%) chili seed. These results weredifferent from the results obtained by Alam.

Farmer seeds showed highest germination percentage (92%) in case of chili seeds

through blotter method. Alam also obtained highest (88%) in farmer chili seeds. In the present study second highesr was recorded in BADC seeds (89.5%) whilelowest was

recorded in seed company seed (38.75%). Alam obtained lowest germination in seed

trader seeds where as in the present study it was 60% from seed trader seeds. Among thecrop seeds , germination performance through blotter method, okra from BADC, brinjal

from seed company and chili from farmer seeds performed better than all other sources

seeds.



Farmer chili seed showed highest germination (90%) in the earthen pot method.

Second highest germination (71.5%) was recorded in BADC seed. Seed trader seeds

germinated 50% whereas BRAC and company seed germinated 40% and 28.5%respectively which far belowas comared to other sources seeds.

In case of chili seeds, highest length was recorded from seed compsny seed 10.25

cm followed by BRAC seed 10 cm whereas length recorded was 9 cm from BADC, seedtrader and farmer chili seeds. These all results recorded were statistically non significant.

Of the DM weight, BRAC and seed company seeds stood highest (26 mg) while it

was recorded 21 mg and 20 mg respectively from the seed trader and BADC seeds.Lowest results were obtained from farmer chili seeds.

CONCLUSION

Inspite of less prevalence of seed borne fungi, BRAC and seed company chiliseeds yielded least germination but vigour while BADC and farmer chili seeds showed

higher germination and comparatively good vigour inspite of higher prevalence of seed

borne fungi. Seed trader chili seed possessed highest prevalence of seed borne fungi and

showed less germination but higher vigour.Over all for reduction of seed borne disease s and also to obtain higher yield care

should be paid to health test. In this case, BRAC and seed company seeds and to someextents BADC seeds have less prevalence of seed borne fungi but BRAC & LSC should

give attention to other parametres to increase the planting value of crop seeds. Farmer

and seed trader seeds are not good for planting at all.

fungal efect on the planting value of chili seeds

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