ABSTRACT
A field trial was conducted in 2017 cropping season at Michael Okpara University of Agriculture, Umudike to test the impact of some agricultural effluents on the control of leaf spot disease of Telfairia occidentalis Hook f. (fluted pumpkin). The experiment was laid out in Randomized Complete Block Design (RCBD) and replicated four times. The effluents from rice, cassava, corn, oil palm and a control (sterile water) were applied at 20ml/plant two weeks after germination at plant base and data collected until after 14weeks of planting. The parameters considered were disease incidence, disease severity, growth and yield parameters. Samples of diseased leaves were taken from field to the laboratory for pathogenicity test, isolation, identification and characterization of the pathogen. Results obtained showed that disease incidence and severity were statistically reduced in treated plants. Rice effluent scored 31.25% for disease incidence, oil palm had 32.50% disease incidence which were significantly (P<0.05) lower than control which had 75% disease incidence. Disease severity was least in plants treated with oil palm effluents (1.59), followed by rice (1.75) and were statistically (P<0.5) lower than the control which had highest disease severity (4.83). Generally all the effluents were observed to enhance growth in all the parameters considered when compared with the non-treated plants (control). For instance, rice effluent gave best vine length (247.33cm) followed by corn effluent (199.59cm) and were statistically higher than the untreated control which had least vine length (137.58cm). The result of effluents on yield of T. occidentalis was significantly different (P<0.05) from the control, rice effluent gave the best yield (7.4kg/ha), followed by cassava effluent (5.8kg/ha), palm oil effluent (5.4kg/ha), corn effluent (3.4kg/ha). The least weight was recorded by the untreated control (2.0kg/ha). Pathogenicity test result showed that the organism was able to induce leaf spot on the seedlings and the organism from infected leaves was identified as Xanthomonas spp. In this study therefore, the efficacy and potency of agro effluents was demonstrated to be useful in control of bacterial leaf spot disease of fluted pumpkin. So farmers can use this low cost organic control approach to minimize the risk of leaf spot incidence in the field since they are readily available and affordable.
TABLE OF CONTENTS
Title page i
Declaration ii
Certification iii
Dedication iv
Acknowledgements v
Table of contents vi
List of Tables x
List of Plates xii
Abstract xiii
CHAPTER
1: INTRODUCTION 1
Objectives of the Study 5
CHAPTER
2: REVIEW OF RELATED LITERATURE 6
2.1 Diseases
of T. occidentalis 6
2.1.1 Bacterial
diseases 6
2.1.2 Fungal
diseases 9
2.1.3 Viral
diseases 12
2.1.4 Nematode
diseases 13
2.2 Management
of Diseases of T. occidentalis 13
2.2.1 Cultural
methods 13
2.2.1.1 Field control 13
2.2.1.2
Preparation of planting material 14
2.2.1.3 Planting/
harvesting time 14
2.2.1.4 Crop
rotation 15
2.2.2 Physical
control 15
2.2.3 Chemical
control 15
2.2.4 Biological
control 17
2.3 Insect
pests of Telfairia occidentalis 18
2.4 Incidence
of Bacterial Leaf Spot 20
2.4.1 Taxonomical
characteristics of bacterial leaf spot Pathogen 20
2.4.2 Epidemiology
of bacterial Leaf Spot Disease 21
2.4.3 Host
Range of Xanthomanas cucurbitae 21
2.4.4 Mode of
Entry of Xanthomanas cucurbitae into host 21
2.5 Adverse
effects of Synthetic Chemicals 22
2.6 Use of
Agricultural effluents in Disease Management 25
2.7 Active
Ingredients and Phytochemicals of Agro Effluents under Investigation 27
CHAPTER
3: MATERIALS AND METHODS
3.1 Field Experiment 31
3.1.1 Study
area 31
3.1.2 Field
preparation and layout 31
3.1.3 Soil
sampling and analysis 31
3.1.4 Source
of seeds 32
3.1.5 Seed
preparation 32
3.1.6 Source
of afro effluents used 32
3.1.7 Collection
of agricultural effluents use as biopesticides 32
3.1.8
Application of agro effluents 33
3.1.9 Field
assessment of disease incidence and severity 33
3.1.10 Assessment
of growth and yield parameters 33
3.2 Lab
Experiment 34
3.2.1 Sterilization
of glass wares and inoculation chamber 34
3.2.2 Preparation
of the culture medium 35
3.2.3 Isolation
of the pathogen 35
3.2.4 Preparation
of the inoculums 35
3.2.5 Identification Pathogen 35
3.2.6 Pathogenicity
test 35
3.2.7 Morphological
and biochemical test for the identification of the pathogen 36
3.3 Experiment 2: Pot Trial 37
3.3.1
Application of the effluents in the pot
work 38
3.3.2 Data
collection in pot work 38
3.4 Statistical
Analysis 38
CHAPTER
4: RESULT AND DISSCUSSIONS 39
4.1 Effect
of Agro Effluent on Growth Parameters 6weeks after Planting (6WAP)
in the Field. 39
4.2 Effect of Agro Effluent on Disease
Incidence, Severity and Growth Parameters at Eight weeks after planting (8WAP)
in the field. 41
4.3 Effect of Agro Effluent on Disease
Incidence, Severity and Growth Parameters at Ten weeks after planting (10WAP)
in the field. 43
4.4 Effect of Agro Effluents on Disease
Incidence and Severity, and Growth Parameters
(12weeks
after planting) 45
4.5 Effect
of Agro Effluents on Disease Incidence and Severity, Growth
(14weeks
after planting) 47
4.6 Effect
of Agro Effluents on Yield of Telfairia
occidentalis 48
4.7 Morphological
Characterization of Leaf Spot Pathogen in the Laboratory 49
4.8
Confirmation by Pathogenicity test 50
4.9 Soil Analysis and Characterization of
Experimental Site 51
4.10 Effect
of Agro Effluents on Growth parameters of T.
occidentalis in Pot work
at Six weeks after
planting 53
4.11 Effect of Agro Effluents on Growth
parameters of T. occidentalis in Pot
work
at Eight weeks after planting 55
4.12 Effect of Agro Effluents on Growth
parameters of T. occidentalis in Pot
work at Ten weeks after planting 59
4.13 Effect of Agro Effluents on Disease
Incidence, Severity and Growth parameters
of T. occidentalis in Pots at 12Weeks after planting 61
4.14 Effect of Agro Effluents on Disease
Incidence, Severity and Growth parameters
of T. occidentalis in Pots at 14Weeks after planting 62
4.15 Effect of Agro Effluents on Disease
Incidence, Severity and Growth parameters
of T. occidentalis in Pots at 16Weeks after planting 63
4.16 Effect
of Rates of treatment on Growth Parameters of T. occidentalis
in
Pot Experiment at 8, 10, 12, 14 and 16Weeks after planting. 65
4.17 Effect
of Rates of treatment on Disease Incidence and Severity on
T. occidentalis
in Pot experiment at 8, 10, 12, 14 and 16WAP 66
4.18 Effect of Effluents on Leaf Yield of T. occidentalis in Pot Experiment 69
4.19 Effect of Rates of Effluents on Yield of T. occidentalis at 9 and 19WAP 69
Discussion 79
CHAPTER
5: CONCLUSION AND RECOMMENDATION 82
5.1 Conclusion 82
5.2 Recommendations 83
References 84
Appendices
99
LIST OF TABLES
4.1
Effect of Agro effluents of Growth of
T. occidentalis in the Field at
6Weeks after planting 41
4.2
Effect of Agro
Effluent on Growth parameters and Disease Incidence and Severity
at
8Weeks
after planting 43
4.3
Effect of Agro Effluent on Growth
parameters and Disease Incidence and Severity
at 10Weeks
after planting 45
4.4 Effect
of Agro Effluent on Growth parameters and Disease Incidence and Severity
at 12Weeks
after planting 47
4.5 Effect of Agro Effluent on Growth
parameters and Disease Incidence and Severity
at 14Weeks
after planting 49
4.6 Morphological and Biochemical
characterization of leaf spot pathogen
of T. occidentalis. 51
4.7
Soil Analysis of Experimental Site 54
4.8 Effect of Agro Effluents on Growth
parameters of T. occidentalis in
Pot
work at 6Weeks after planting 57
4.9 Effect of Agro Effluents on Growth
parameters of T. occidentalis in
Pot work at 8Weeks after planting 59
4.10 Effect of Agro Effluents on Growth
parameters of T. occidentalis in
Pot work at 10weeks after planting 61
4.11 Effect of Agro Effluents on Disease
Incidence, Severity and Growth
parameters of T. occidentalis in pots at 12Weeks after planting 63
4.12 Effect of Agro Effluents on Disease
Incidence, Severity and Growth
parameters
of T. occidentalis in pots at 14Weeks
after planting 65
4.13 Effect of Agro Effluents on Disease
Incidence, Severity and Growth parameters of
T.
occidentalis in Pots at 16Weeks after planting 67
4.14 Effect
different Rates of treatment on Growth parameters of T. occidentalis
in Pot experiment at 8, 10, 12, 14 and 16Weeks
after planting 69
4.15 Effect of Rates of effluents on Disease
Incidence and Severity of T. occidentalis
at 10, 12, 14 and 16Wweeks after planting. 71
4. 16
Effect of effluents on yield of T.
occidentalis in pot experiment at 9 and 19Weeks after planting 73
4.17 Effect
of rates of effluents on yield of T.
occidentalis at 9 and 19weeks after
Planting. 75
LIST
OF PLATES
Plates Page
1: Experimental field of Telfairia occidentalis 54
2: T.
occidentalis growing in a pot layout 75
3: Culture of Xanthomonas cucurbitae on Nutrient agar 76
4: Confirmatory Pathogenesity test 77
5: Bacterial leaf spot symptoms on Telfairia occidentalis 78
CHAPTER
1
INTRODUCTION
Telfairia
occidentalis Hook f. belongs to Cucurbitaceae family and indigenous to
Southern Africa. It planted in
many parts of southern Nigeria for
its delicious and succulent leaves mainly used as vegetables in Nigerian foods
(Esiaba, 2000; Burkil, 2004). The seeds of T.
occidentalis (fluted pumpkin) are high in fat, protein and therefore
contribute to a well-balanced diet (Okon and Udoffot, 2012). It is drought
tolerant, dieocious, perennial that is climbing by coiled, often branched tendrils
(Bosa et al., 1983).
This
vegetable is planted in many
parts of southern Nigeria for
its delicious and succulent leaves (Akoroda, 1990). T. occidentalis
requires enough space and moisture, air and undisturbed movement. As reported by Haering and Evanylo (2005), it’s a
better option to plant this crop near water source or riverside due to the
fertile state of such areas and this will aid farmers in the irrigation of
fluted pumpkin beds. This vegetable may be planted with yam (Dioscorea spp.) or cassava (Manihot
spp.) which it uses for support (Nkang
et al., 2002).
In Nigeria, there are two cultivars, 'ugu-ala' and 'ugu-elu (Odiaka and Shippers, 2004). Ugu-ala according to
the authors has broad leaves that are very succulent, seeds are small and
black, with stems that are thick and slow growth whereas 'ugu-elu' has
considerable high rate of growth, small leaves, thin stems, with seeds
that are large and brownish in colour and great viability rate.
Consumers prefer and make high demand of ugu-ala due
to its broad juicy foliage while the fast emergence and high
growth rate of 'ugu-elu' is preferred by farmers because of quick returns
(Odiaka and Shippers, 2004). The seed is often polyembryonic, which is useful
for multiplication and in breeding. It is a usual practiced to stake this
crop which aids reduce disease infection. T.
occidentalis may be staked individually or for purpose of fruit production,
with rattan sticks.
Staking is not necessary in dry season during the dry season for crops for the production of leaves
since there is less incidence of disease. According to Akubue et al. (1990), staking does not have a
major effect on the yield of leaves. The first pruning is 4 weeks after emergence to stimulate branching
and increase the growth (Odiaka and Shippers, 2004).
Irrigation is important for leaf or fruit production particularly under single
cropping conditions in dehydrated times. Irrigation can be done twice a week.
The use of organic manure or inorganic fertilizers is common in conventional
systems. As reported by Odiaka (2000), the female plants are more vigorous than
male ones and produce higher crop yields. According to the author, the removal
of a part of the male plant is needed to get female plants and hence high leaf
and fruit yield.
|
|
The stem is angular and glabrous
which becomes fibrous when old (Gruben and Denton, 2004). The leaves are
arranged spirally, with palmate compound leaflets (Bassey and Opara, 2016)
without stipules and has moderately long petioles.
|
T. occidentalis is a rain fed crop but can be grown
under irrigation of 2-3 irrigations per week (Alegbejo, 2012). Seed size
affects vigour and seedling germination (Gruben and Denton, 2004), viability is
about 63-69% and germination takes 7-14 days. Large seeds show good growth
potential (number of leaves, branches and uniformity of seedlings). Fruit
growth is sigmoid over 8weeks, but is rapid between 2-6 weeks. Physiologically
mature fruits are obtained 9weeks after fruit set (Alegbejo, 2012). Fruits may
be stored in open shade for 1–2 months at the most. Most often they are
transported by rail from the eastern part of Nigeria to the middle zone of the
country. Before the fruits are sold, they are graded according to size (small,
medium and large). In the market they are placed in heaps and sold as heaps or
singly. Seeds are left in the fruits until they are used for planting or
consumption.
The
nutritional values of Telfairia occidentalis are enormous. The leaf
composition per 100 g edible portion is: water 86.4g, energy 147kJ (47kcal),
protein 2.9g, fat 1.8g, carbohydrate 7.0g, fibre 1.7g (Gruben and Denton,
2004). The high content of mineral nutrients, especially of Mg, Fe and K, and
of carotene and vitamin C of the vegetable make the leaves potentially useful
as food supplements (Akalazu et al.,
2011). The
seeds are high in essential amino acids (except lysine) and are comparable with
that of soybean meal with 95% biological value (Bassey and Opara, 2016). The composition of the seed per 100g
edible portion is: water 6.2g, energy 2280kJ (543kcal), protein 20.5g, fat
45.0g, carbohydrate 23.5g, fibre 2.2g, Calcium 84mg, Phosphorous 572mg (Leung et al., 1968). The fruit pulp has a
protein content of about 1.0%, the main constituents of the seed oil are oleic
acid (37%), stearic and palmitic acid (both 21%), linoleic acid (15%) (Gruben
and Denton, 2004).
Medicinally, T.
occidentalis has been reported to contribute to human health care by many
scientists. In Nigeria, the herbal preparation of the plant has been employed
in the treatment of such situations like sudden attacks of convulsion, malaria,
and anemia (Gbile, 1985). Its action against hypercholestolaemia has been
investigated and reported (Eseyin et al.,
2005 and Adaramoye et al., 2007). The
plant has also been reported to possess other medicinal properties which
include anti-malarial (Okokon et al., 2009),
anti-diabetic (Aderibigbe et al.,
1999), antioxidant, and antimicrobial (Eseyin et al., 2010) activities. Scientific evidence supporting its use as
an anti-anaemic medicine has also been documented (Alada, 2000). Juices
prepared from fluted pumpkin leaves have been claimed to increase the
haemoglobin levels rapidly in the human body during the treatment of anemia. It can be inferred that the ability of the plant
to combat certain diseases may be due to its antioxidant and antimicrobial
properties and its minerals (especially Iron), vitamins (especially vitamin A
and C) and high protein contents (Kayode and Kayode, 2011). It contains
some phytochemicals such as saponin, alkaloid, phenol and tannin (Sofowora,
1996) which have curative properties. T. occidentalis vegetable and
fruit enhance regular bowel movement, prevent constipation, heart diseases,
stroke, high blood pressure and accumulation of cholesterol (Etukudo, 2003).
The phytochemical
screening of the extract of T. occidentalis by Oyewole and Abalaka
(2012) indicated the presence of gly-cosides, saponins, flavonoids, phenolics
and steroids and that the extract showed a higher antibacterial activity
against E. coli (20 ±0.58mm at 500mgmg.ml), S. faecalis (6 ±
1.10mm at 5.0mg) and S. typhi (11±0.70mm at 50mg/ml) and hence, can be
used for the treatment of infections by the test organisms.
The
numerous uses and potential of fluted pumpkin in Nigeria notwithstanding, the
average yield of pumpkins in Nigeria remains low due mainly to biotic and
abiotic stresses (Times and Chikezie, 2016). These challenges includes
difficulty to identify the sex (Odiaka, 2000), spot diseases induced by various
pathogenic groups of fungi and bacteria (Burrows, 2013), Leaf spots which
result in defoliation (Nix, 2014), Yield losses due to natural infection
(Shaner and Finney, 1976; Ibrahim, 1975), inappropriate farm management as well
as pre and post harvest losses. These diseases and conditions pose a serious
threat to the crop in the coming future.
Several
control measures and management practices are adopted by different farmers in
control of fluted pumpkin leaf spot disease, such as the use of resistant
varieties, crop rotation, use of pesticides. However, non-availability of land
as a result of consistent increase in population does not permit the practice
of good farming system for crop production. Moreso, many farmers in developing
countries like Nigeria cannot easily have access to resistance varieties due to
high cost of treated seeds. The use of synthetic chemicals is recently
discouraged due to its harmful effect on the environment and cost effect on
production. Hence, the option is the use of biological methods such as use of
agricultural effluents, use of plant extracts in management of fluted pumpkin
leaf spot disease. The utilization of agricultural Effluents in management of
crop diseases are reported (Uwah et al.,
2011, Onwudike et al., 2015; Ubalua,
2017; Al-Qhatani, 2011; Iwuagwu, 2017;
Sylvester and Soh-fong, 2018.) and their efficacy via use of
effluents of cassava, rice, oil palm, corn etc.
Aim and Objectives of the study
The aim of this
study was to use agricultural effluents to control bacterial leaf spot disease
of Telfairia occidentalis (fluted pumpkin) in Umudike.
Objectives of the Study
The objectives of this study included;
· To
isolate and identify the causal agents of leaf spots of Telfairia occidentalis.
· To
conduct pathogenicity tests on young Telfairia
occidentalis seedlings in pots in
vivo.
· To
test the efficacy of Agricultural Effluents on control of leaf spots of T. occidentalis and on yield
performance.
Login To Comment