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(EPNs) in Vegetable and Strawberry Growing Areas in Mountain Province. Benguet State University, La Trinidad, Benguet.

Adviser: Luciana M. Villanueva, PhD.

ABSTRACT

A survey was conducted in five vegetable and strawberry growing municipalities of Mt.

Province from January to March 2011 to determine the presence of entomopathogenic nematodes (EPNs) and how they are affected by soil pH, texture and crops.

Result showed that 19 out of 32 sites were positive for EPNs. Sabangan showed the highest recovery frequency of 46.15% followed by Besao and Bauko with 24.44% and 22.73%, respectively. Bontoc with only one site has 15.38% recovery frequency while Sagada has the least with 10.81%. Although soil pH and texture did not significantly affect the presence of EPNs in 5 municipalities surveyed, it was noted that higher number of EPNs was detected in areas with pH ranging from 4.00-5.99. The least number was collected in areas with soil pH ranging from 3.00-3.99, 6.00-6.99, and 7.00-7.99. On the other hand, most of the positive samples were collected in silt loam with 89.47% followed by loam with 7.89% and the least was sandy loam soil with 2.63%. Conversely, the presence of EPNs was significantly influenced by crops. The frequency of occurrence of EPNs was highest in soil samples from potato 42.86%

followed by cabbage and pepper, with 11.63% and 10%, respectively.

Results of the investigation indicate that the presence of EPNs is dependent on soil pH, soil texture and crops planted. However, these findings need to be verified.

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Bibliography. . . .. . i

Abstract . . . i

Table of Contents . . . ii

INTRODUCTION . . . 1

REVIEW OF LETIRATURE . . . 2

Life Cycle . . . 3

Mutualistic Bacteria . . . 4

Behavioral Ecology . . . 4

Efficacy . . . 5

MATERIALS AND METHOD . . . 6

Geography and Collection of Soil Samples . . . 6

Isolation of EPNs . . . 12

Determination of Soil Ph . . . 13

Soil Texture Classification . . . 13

Data Gathered . . . 14

RESULTS AND DISCUSION . . . 15

Effect of Soil pH . . . 15 Effect of Soil Texture . . . 16

Effect of Crops . . . . 19

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Conclusion . . . 23

Recommendation . . . 23

LITERATURE CITED . . . 24

APPENDICES . . . 26

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INTRODUCTION

Nematodes are a diverse group of invertebrates abundant as parasites or free living forms in soil, fresh water, and marine environments. Barker (1998) stated that there are more than 15,000 described species that represent only a small portion of the total members in Phylum Nematoda. The soil is particularly rich habitat for nematodes with about 26% described genera inhabiting soil as bacterivores, fungivores, omnivores, predators or plant parasites. Added to this are soil dwelling stages of insect parasites referred to as entomopathogenic nematodes (EPNs) (Wharton, 1986).

Entomopathogenic nematode (EPNs) are extra ordinarily lethal to many important soil insect pests, yet they are safe to plants and animals. Unlike chemicals, nematode applications do not require mask or other safety equipment, re entry time, residues;

ground water contamination; chemical trespass and pollution are not issues. Thus development of EPN technology will be a great help for researchers and vegetable growers to produce good quality and safe food for consumers

Recognizing the hazards of pesticides to man and the environment, many countries in the world is considering biological control agents such as entomopathogenic nematodes (EPNs) as the best alternative to chemical control of plant diseases and pests (Souto et al., 2004).

The study was conducted to determine the presence of entomopathogenic nematodes (EPNs) in vegetable and strawberry growing areas in Mt. Province and how they are affected with soil texture, pH and crops.

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REVIEW OF LITERATURE

Entomopathogenic nematodes have been known since the 17th century but it was only in the 1930’s that serious consideration was given to using nematodes to control insect (Nickle, 1984). This nematode has been found infecting grubs of the Japanese beetle, Popilla japonica, at the Travis stock Golf course near Haddon field, New Jersey.

Entomopathogenic nematodes are adapted to most climatic conditions in hot, temperate and cold zones, distributed from lowlands to high alpine altitudes. S.

carpocapsae and S.feltiae are widely distributed in temperate regions. H.bacteriphora is common in regions with continental and Mediterranean climates, and H.indica is found throughout much of the tropics and subtropics (Steiner, 1996).

Currently, there are two genera which contain the most important species of entomopathogenic nematodes; Steinernema and Heterorhabditis (Lewis, 2000). Species in these genera have a global distribution. They exhibit differences in host range, infectivity and environmental tolerances (Hominick et al., 1996). Most entomopathogenic nematodes described belong to the genus Steinernema, a total of 24 species have been isolated, and four species have been commercialized; S.carpocapsae, S. feltiae, S.riobravis and S.capterisci. Of the Heterorhabditis species H.bacteriophora and H.megidis have been commercialized (Booth, 2000).

Life Cycle

Steinernematids are similar to heterorhabditids in general life cycle and gross morphology (Wouts, 1984). The major difference between the two families is in the reproductive strategies. Steinernematids are amphimictic, they require a male and female

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infective juvenile to invade an insect host to produce progeny. In the case of heterorhabditid, adults resulting from the infective juveniles are hermaphrodites;

therefore only one juvenile is needed to enter the host for progeny production (Hazir et al., 2003).

The infective stage of entomopathogenic nematodes (third-stage dauer juveniles) seeks and invades larvae of soil dwelling insect species (Klein, 1990). They enter the insect host through natural body openings, the mouth, anus, or respiratory inlets (spiracles) and then penetrate into the blood cavity from the gut (Poinar 1990).

Heterorhabditis penetrates through chinks in the insects interskeletal membranes by scratching away with special tooth (Bedding and Molyneux, 1982). They release bacterium through anus for steinernematids and through mouth by hetrorhabditids (Poinar, 1966). The toxins produced by the developing nematodes (Burman, 1982) and bacteria cause septicemia and kill the insect host within 24-48 hours after infection (Akhurst and Boemere, 1990).

Insects use anti bacteial protiens and phagocytosis followed by nodule formation to counteract the bacterial cells. It may also encapsulate nematodes followed by melanization. However, in some cases, nematodes overcome the insect’s defense and successfully infect its host. This is in relation to the nematodes surface coat proteins that suppresses the host immune response (Wang, 1998). Moreover, the invading nematodes immuno –inhibiting factors that destroy the antibacterial factors produced by the insect and allow the mutualistic bacteria to produce insecticidal toxins that rapidly kill the host (Bowen et al., 1998)

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Mutualistic Bacteria

Steinernema and Heterorhabditis are associated with mutualistic bacteria Xenorhabdus and Photorhabdus respectively. Xenorhabdus and Photorhabdus are motile gram negative, facultative, none spore forming, anaerobic rods in the family Enterobacteriaceae. These symbiotic bacteria are vectored in the insect’s hemocoel by the nematode infective juvenile (Forst et al., 1996). The difference that occur between the 2 bacterial genera is, most Photorhabdus spp. are luminescent and catalase positive, where as Xenorhabdus spp. have no luminescence and are catalase negative (Hazir et al., 2003)

Behavioral Ecology

EPNs employ different foraging strategies to locate and infect hosts. The intermediate foraging strategist (S. riobrave and S.feltiae) infects insect that occur just below the soil surface, such as prepupae of lepidopterous insects, fungus gnats, or weevil larvae. The sit and wait strategist or ambushers (S. carpocapsae) are characterized by low motility which search at or near the soil surface. They infect mobile host species such as codling moth, cutworms and mole crickets. At the other extreme, foraging strategy or cruiser (S. glaseri and H.bacteriophora) are characterized by high motility and are distributed throughout the soil profile. They infect sedentary host such as scarab and lepidopterous prepupae and pupae (Hazir et al., 2003).

Various biotic and abiotic factors can influence the successful use of entomopathogenic nematodes as biological control agent. The persistence of EPNs in natural areas depends on the dauer larvae’s ability to disperse and persist until it can locate a suitable host. Extrinsic factors such as temperature, soil moisture, soil texture, pH, and UV radiation affect their dispersal and persistence. Furtheremore, many soil

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dwelling nematodes have evolved behaviors resulting in reduced host finding attachment and penetration by infective juveniles. Some nematodes that have been isolated from host cadavers in the field have restricted host range (e.g. S. kushidari and S.scarabaei are adapted to scarab larvae (Stock and Koppenhoefer, 2003). S. scapteresci is adapted to mole cricket and poorly infect other insects (Grewal, 1993). Among the biotic factors (natural enemies) are bacteria, fungi, mites, predatory nematodes, tardigrades and collembolans. Mites appear to be especially voracious nematode feeders (Walter, 1987).

Efficacy

Several studies have shown effectiveness of entomopathogenic nematodes in recent years. EPNs have been applied successfully against soil inhabiting insects (as soil application) as well as above-ground insects (foliar spray) in cryptic habitat (Shapiro - Ilan et al., 2006.) In a golf course ecosystem, the application of Heterorhabditis bacteroiphora, an introduced nematode, significantly reduced the abundance, species richness, maturity and diversity of the nematode community (Somaseker et al., 2002).

Further laboratory test showed that S. carpocapsae alone infected more than 250 insect species from over 75 families in 11 0rders (Poinar, 1983).

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MATERIALS AND METHODS

Soil samples were collected from strawberry and vegetable growing areas in Mt.

Province and further laboratory study was done at STVRDC laboratory, Benguet State University La Trinidad, Benguet from January to April 2011.

A. Geography and Collection of Soil Samples

Mt. Province is known to be the Philippines biggest and highest chain of mountains. The province is bounded on the north by Kalinga, on the south by Benguet and Ifugao, on the east by Isabela, and on the west by Ilocos sur and Abra. Mt. Province is politically subdivided into 10 municipalities and 144 barangays. It has a total land area of 209,733 hectares, 23% is classified as alienable and disposable, and 77% as forest lands. Mt. Province is characterized by towering peaks and sharp ridges on its central and western part while the eastern portion features gently sloping and rolling foothills. The Province falls on type III climate category that is characterized by uneven distribution of rains throughout the year and this cover the eastern part of the province.

A survey was undertaken from February to March 2011 to assess the distribution of EPNs in vegetable and strawberry growing areas in Bauko, Sabangan, Bontoc, Besao, and Sagada, Mt. Province.

Soil samples were collected from nine (9) vegetable sampling sites in Bauko, five in Sabangan, one in Bontoc, twelve in Sagada and nine in Besao (Figures 1- 5), A total of 174 samples were collected from the 5 municipalities. About 0.5 kg comprising five to 10 sub-samples were collected randomly per area. The samples were placed on properly labeled plastic bags and were brought to the laboratory for nematode isolation.

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D B A

Figure 1. Sampling sites in Bauko, Mt. Province: (A) Buga, Mt. Data, (B) Sintu proper, (C) Sintu, (D) Monamon

D

C

A

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A

B

Figure 2. Sampling sites in Sabangan, Mt. Province: (A) Pengew, (B) Capinitan

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A

B

Figure 3. Sampling sites in Lanao, Bontoc, Mt. Province: (A) site 1, (B) site 2

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A A

B B

Figure 4. Sampling sites in Sagada, Mt. Province: (A) Nalabasan, Poblacion, (B) Madongo, (C) Petaad, Ambasing, (D) Legleg, Ambasing

C D

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A A

B B

C

Figure 5. Sampling sites in Besao, Mt. Province: (A) Amdakig, (B) Banao, (C) Lake Danum, (D) Suquib

D

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B. Isolation of EPNs

Entomopathogenic nematodes (EPNs) were isolated from soil by using lesser wax moth, Achroia grisella larvae as bait (Figure 6). About 250 g of soil was placed in each improvised baiting container. To provide aeration and at the same time prevent the escape of wax moth larvae, wire mesh was provided in the plastic cover of the baiting container (Figure 7). Around 10 larvae were placed per container to serve as bait for the nematodes.

After 2-3 days, the larval cadavers were retrieved from the soil and washed with distilled water and arranged in a petri plate lined with moist filter paper. The infected insect was examined under a dissecting microscope for the presence of EPNs.

Figure 7. Plastic containers with soil samples collected from different municipalities in Mt. Mountain Province Figure 6. Lesser wax moth (Achroia

grisella) larvae used as bait

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D. Determination of soil pH

About 30 g of soil samples were air dried in the laboratory for 3 days. Grinding of soil samples was done using mortar and pestle prior to pH determination which was done after calibrating the pH meter (Figure 8).

E. Soil texture classification

Following the procedure of Robinson (2005), soil classification was done. About 50 cc of soil taken from samples collected was moistened with 10 ml water to determine if it will form a ball (Figure 8). The soil was squeezed in the palm of the hand and depending on the form that it would create; soil texture was determined.

Sand- Soil either does not form a ball or forms a ball but easily breaks when bounced at the palm.

Figure 8. Determination of soil pH using a pH meter

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Loam- Soil can be formed into a ball and a ribbon less than 2.5 cm.

Clay- Soil can be formed into a ball and a ribbon more than 2.5 cm.

Data Gathered

1. Presence of EPNs 2. Soil pH

3. Soil Texture

Figure 9. Classification of soil texture by feel method

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15 RESULTS AND DISCUSSION

Table 1 shows the abundance and recovery frequency of EPNs in vegetable and strawberry growing areas in Mt. Province. EPNs were recovered from 38 samples out of 174 soil samples collected (21.84%) and 19 positive sites out of 32 sites sampled (59.38%). Although not significantly different, the highest recovery was recorded in Sabangan, followed by Besao, Bauko, Bontoc, and Sagada with 46.15, 24.44, 22.73, 15.38 and 10.81%, respectively. In terms of EPN abundance, Bontoc with only 1 site that grows vegetables gave 100% followed by Besao (85.71%), Sabangan (80.00%), Bauko (62.50%) and Sagada (27.27%).

Effect of Soil pH

The effect of soil pH on the recovery frequency of EPNs in five municipalities of Mt. Province is shown in Table 2. Although not significantly different as shown by Pearson’s chi-square test, most of the EPNs were recovered from pH-4.00-5.99. This is true in all the municipalities surveyed. In very acidic soil (pH 3.00-3.99), EPNs were only detected in Sabangan, while at pH range of 6.00-6.99, they were found only in Bauko. In highly alkaline soil (7.00-7.99), the EPNs were only recovered in Besao.

Results of the study confirmed the findings of Rosa et al., (2000) that most of the EPNs were recovered from soil with pH below 6.00. On the other hand, according to Herrera et al (2007) soil pH does not significantly affect occurrence of EPNs although they are easily isolated from pH range of 5.01 to 8.0.

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Table 1. Abundance and recovery frequency of entomopathogenic nematodes (EPNs) in strawberry and vegetable growing areas/municipalities in Mountain Province

MUNICI- PALITIES

TOTAL SITES

NO. OF POSITIV E SITES

ABUN- DANCE

(%)a

TOTAL SOIL SAMPLE

S

POSITIV E SOIL SAMPLE

S

RECOVERY FREQUENC

Y (%)b

Sabangan 5 4 80.00 13 6 46.15

Bauko 8 5 62.50 66 15 22.73

Bontoc 1 1 100.00 13 2 15.38

Sagada 11 3 27.27 37 4 10.81

Besao 7 6 85.71 45 11 24.44

GRAND

TOTAL 32 19 59.38 174 38 21.84

a (Number of positive sites/ number of total sites) x 100

b (Number of positive samples /number of total samples) x 100

Table 2. Recovery frequency (%) of positive soil samples for EPN by soil pH in vegetable and strawberry growing areas in Mt. Province per municipality

MUNICIPALITIES

pH RANGE Sabangan Bauko Bontoc Sagada Besao

3.00 - 3.99 6.69 - - - -

4.00 - 4.99 15.38 3.03 7.69 10.81 20.00

5.00 - 5.99 23.07 16.66 7.69 - 2.00

6.00 - 6.99 - 3.03 - - -

7.00 - 7.99 - - - - 1.00

Total No. of Samples 13 66 13 45 37

Positive Soil Samples (%) 46.15 22.72 15.38 24.44 10.81

Effect of Soil Texture

The effect of soil texture on the incidence of EPNs by municipality is shown in Table 3. Statistical analysis showed that except for Bauko (P=0.029), the presence of EPN was not significantly affected by soil texture. However, in most of the municipalities surveyed, the EPNs were mostly detected from silt loam and loam except for EPNs collected from Bontoc which were recovered from sandy loam soil.

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Regardless of municipality, soil texture has no significant effect on the occurrence of EPNs (Table 4). However, most of the positive samples were noted from silt loam followed by loam and sandy loam with 89.47, 7.89 and 2.63 % recovery frequency, respectively.

Our results are similar to the findings of Mracek et al., (2004) and Rosa et al., (2000) that EPNs were mostly recovered from light soils such as silt loam and sandy loam except for S. kraussei which can tolerate both silt/clay organic soils. According to Mraceket et al., (2005) heavy soils decrease the nematode mobility which could be the reason why no EPNs were recovered from clay loam to heavy clay in all the sampling sites (Figure 10).

Table 3. Number and recovery frequency (%) of positive soil samples collected from vegetable and strawberry growing areas in Mt. Province as influenced by soil texture

SOIL TEXTURE

NUMBER OF POSITIVE SOIL SAMPLES

RECOVERY FREQUENCY*

Sand - -

Sandy loam 1 2.63

Silt loam 34 89.47

Loam 3 7.89

Clay loam - -

Light clay - -

Heavy clay - -

GRAND TOTAL 38 100

* (number of positive soil samples/ total number of positive soil samples) x 100

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0 5 10 15 20

Sand Loamy sand Silt

loam Loam Clay loam Light

clay Heavy clay

Recovery freqency (%)

Soil texture Bauko

0 5 10 15 20

Sand Loamy sand Silt

loam Loam Clay loam Light

clay Heavy clay

Recovery frequency (%)

Soil texture

Besao

0 5 10 15 20

Sand Loamy sand Silt

loam Loam Clay loam Light

clay Heavy clay

Recovery frequency (%)

Soil texture

Sabangan

0 5 10 15 20

Sand Loamy sand Silt

loam Loam Clay loam Light

clay Heavy clay

Recovery frequency (%)

Soil texture

Sagada

0 5 10 15 20

Sand Loamy sand Silt

loam Loam Clay loam Light

clay Heavy clay

Recovery frequency (%)

Soil texture

Bontoc

Figure 10. Influence of soil texture on the distribution of positive samples in vegetable and strawberry growing areas in Mt. Province (a) Sabangan, (b) Bauko, (c) Bontoc, (d) Sagada and (e) Besao

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Table 4. Recovery frequency (%) of positive soil samples for EPNs in vegetable and strawberry growing areas in Mt. Province per municipality as influenced by soil texture

MUNICIPALITIES

SOIL TEXTURE Sabangan Bauko Bontoc Sagada Besao

Sand - - - - -

Sandy loam - - 2.63 - -

Silt loam 13.16 39.47 2.63 10.53 23.68

Loam 2.63 - - - 5.26

Clay loam - - - - -

Light clay - - - - -

Heavy clay - - - - -

Total No. of Samples 6 15 2 4 11

Recovery Frequency (%) 15.79 39.47 5.26 10.53 28.95

Effect of Crops

Figure 11 shows the effect of crops on the recovery frequency of EPNs in different municipalities of Mt. Province. Apparently, crops did not significantly influence the recovery frequency of EPNs in Sabangan. However, in Bauko, significantly higher EPN recovery was recorded in potato, followed by garden pea and cabbage. In Bontoc, EPNs were only detected in beans and banana while in Sagada they were detected only in cabbage, beans and pepper. Similar to Bauko, the highest recovery of EPNs in Besao was recorded in potato, followed by pechay, cabbage and corn. Surprisingly, no EPN was recovered in strawberry areas in Sagada and Besao. This could be due to the fact that strawberry was newly introduced in these two municipalities and therefore the population of insect pests associated with strawberry which are the hosts of EPNs is still very low.

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0 5 10 15 20

Recoveryfrequency(%)

Crops Sabangan

0 5 10 15 20

Recover frequency (%)

Crops

Bauko

0 5 10 15 20

Recovery frequency (%)

Crops

Bontoc

0 5 10 15 20

Recovery frequency (%)

Crops

Sagada

Figure 11. Recovery frequency of positive samples for EPN by crops in vegetable and strawberry growing areas in Mt. Province, (a) Sabangan, (b) Bauko, (c) Bontoc, (d) Sagada and (e) Besao

02 46 108 1214 1618 20

Recovery frequency (%)

Crops

Besao

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On the other hand, regardless of municipality, positive samples for EPNs were significantly affected by crops (Figure 12). The highest recovery frequency was obtained from potato with 47.37%, followed by cabbage (13.16 %), garden pea and beans (7.89%), chinese cabbage and pechay (5.26 %), and carrots, banana, peper, zuccini, and broccoli (2.63 %). According to Garcia del Pino and Palomo (1996a) and Mracek and Webster (1993) habitat preference is related to insect host distribution. Since farmers have been planting potato,cabbage garden pea and beans for quite a long time , the insect pests associated with these crops have already increased their populations ; thus favoring the growth and development of their associated EPNs .

Figure 12. Recovery frequency (%) of positive soil samples for EPNs as influenced by crops

0 10 20 30 40 50

Recovery frequency (%)

Crops

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SUMMARY, CONCLUSION AND RECOMMENDATION

Summary

A survey was conducted in five vegetable and strawberry growing municipalities of Mt. Province from January to March 2011 to determine the distribution of entomopathogenic nematodes (EPNs) and how they are influenced by soil pH, texture and vegetation. Soil samples were brought to the STVRDC Laboratory, Benguet State University, La Trinidad, Benguet for nematode and soil analyses.

EPNs were recovered from 38 samples out of 174 soil samples collected (21.84%) and 19 out of 32 sites sampled (59.38%). Although not significantly different, the highest recovery frequency was recorded in Sabangan followed by Besao, Bauko, Bontoc and Sagada with 46.15%, 24.44%, 22.73%, 15.38% and 10.81%, respectively.

Regardless of municipality, most of the EPNs were detected in pH ranging from 4.00- 5.99. On the other hand, higher number of positive samples were collected from silt loam (89.47%), followed by loam (7.89%) and sandy loam (2.63%) soil. No EPNs were recovered from clay loam, light clay and heavy clay loam.

The presence of EPNs was also influenced by crops. The highest recovery was obtained from potato with 47.37% followed by cabbage (13.16%), garden pa and beans (7.89%), Chinese cabbage and pechay (5.26), and carrots, banana, pepper, zucchini and broccoli (2.63%).

The present study reported for the first time the occurrence of EPNs in Mt.

Province.

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Conclusion

Results of the investigation showed that soil pH, soil texture and crops influenced the recovery frequency of EPNs. Slightly acidic and silty loam soil favored the growth and development of most vegetables including potato. Higher recovery frequency of EPNs in the above mentioned pH range and soil texture could also be related to the insect or nematode populations feeding on these crops which serve as host for EPNs.

Recommendation

Additional surveys are recommended taking into account other factors like soil moisture, temperature, season including altitude.

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APPENDICES

Appendix Table 1. Locality, crop, pH, soil texture and presence of EPN in soil samples collected from Bauko, Mountain Province

SAMPLE

# LOCALITY CROP

AVERAGE SOIL pH

SOIL TEXTURE

PRESENCE OF EPNs

1 Monamon radish 4.67 Silt loam -

2 Monamon carrots 5.69 Silt loam -

3 Monamon radish 4.94 Silt loam -

4 Monamon potato 4.77 Silt loam -

5 Monamon carrot 5.51 Silt loam +

6 Monamon radish 5.95 Silt loam -

7 Monamon radish 6.79 Loam -

8 Monamon carrots 4.84 Loam -

9 Monamon potato 5.34 Silt loam +

10 Monamon potato 5.66 Silt loam +

11 Monamon, site 1 potato 5.34 Silt loam +

12 Monamon cabbage 5.91 Silt loam -

13 Monamon radish 5.31 Loam -

14 Monamon cabbage 5.56 Loam -

15 Monamon radish 6.69 Loam -

16 Monamon potato 5.13 Silt loam -

17 Monamon potato 5.76 Silt loam -

18 Monamon potato 5.5 Silt loam +

19 Monamon potato 5.45 Silt loam +

20 Monamon potato 5.66 Silt loam -

21 Sinto cabbage 6.26 Silt loam -

22 Sinto cabbage 6.07 Silt loam +

23 Sinto garden pea 5.48 Silt loam -

24 Sinto garden pea 6.41 Silt loam +

25 Sinto Proper garden pea 4.71 Silt loam +

26 Sinto proper potato 5.56 Loam -

27 Sinto proper potato 6.00 Silt loam -

28 Sinto Proper potato 5.67 Silt loam +

29 Sinto Proper potato 5.96 Silt loam -

30 Sinto Proper potato 5.94 Silt loam -

31 Sinto proper potato 5.83 Silt loam +

32 Sinto proper cabbage 6.02 Silt loam -

33 Sinto proper cabbage 5.93 Loam -

34 Buga Sinto potato 4.47 Silt loam +

35 Buga Sinto potato 5.84 Silt loam -

36 Buga Sinto potato 5.49 Silt loam +

37 Buga Sinto corn 7.02 Silt loam -

38 Buga Sinto potato 5.89 Silt loam -

(31)

Appendix Table 1. Continued…

SAMPLE

# LOCALITY CROP

AVERAGE SOIL pH

SOIL TEXTURE

PRESENCE OF EPNs

39 Sadsadan beans 5.36 Silt loam -

40 Sadsadan beans 4.37 Loam -

41 Sadsadan beans 6.02 Silt loam -

42 Sadsadan potato 5.24 Silt loam -

43 Sadsadan garden pea 6.26 Silt loam -

44 Sadsadan potato 5.08 Silt loam -

45 Sadsadan potato 4.79 Silt loam -

46 Sadsadan potato 4.86 Silt loam -

47 Sadsadan cabbage 5.05 Silt loam -

48 Mabaay garden pea 4.66 Silt loam -

49 Mabaay garden pea 4.78 Loam -

50 Mabaay potato 5.48 Loam -

51 Mabaay camote 5.70 Silt loam -

52 Mabaay garden pea 4.59 Silt loam -

53 Mabaay garden pea 4.83 Loam -

54 Mabaay carrots 5.73 Silt loam -

55 Mabaay camote 5.49 Silt loam -

56 Mabaay carrots 5.52 Silt loam -

57 Mabaay camote 5.63 Silt loam -

58 Mabaay garden pea 4.84 Loam -

59 Mabaay garden pea 4.68 Silt loam -

60 Mabaay garden pea 5.42 Silt loam -

61 Baayan chinese cabbage 5.09 Silt loam +

62 Baayan chinese cabbage 5.37 Silt loam +

63 Leseb cabbage 3.77 Silt loam -

64 Leseb cabage 4.39 Silt loam -

65 Leseb cabbage 4.69 Silt loam -

66 Leseb cabbage 4.64 Silt loam -

(32)

Appendix Table 1a. Pearson Chi-Square Test Analysis of Independence for EPN presence and soil pH (Bauko, Mountain Province)

SOIL pH PRESENCE OF EPNs

TOTAL

(-) (+)

3 (3.00-3.99) 1 0 1

4 (4.00-4.99) 16 2 18

5 (5.00-5.99) 26 11 37

6 (6.00-6.99) 7 2 9

7 (7.00-7.99) 1 0 1

Total 51 15 66

Pearson chi2 (4) = 3.0056 Pr = 0.557; X2(.05,4)= 9.48 NS- not significant

Appendix Table 1b. Pearson Chi-Square Test Analysis of Independence for EPN presence and soil texture (Bauko, Mountain Province)

SOIL TEXTURE PRESENCE OF EPNs

TOTAL

(-) (+)

Loam 13 0 13

Silt loam 38 15 53

Total 51 15 66

Pearson chi2 (4) = 4.7614 Pr = 0.029; X2(.05,4)= 3.841 S-significant

(33)

Appendix Table 2. Locality, crop, pH, soil texture and presence of EPN in soil samples collected from Sabangan, Mountain Province

SAMPLE

# LOCALITY CROP

AVERAGE SOIL PH

SOIL TEXTURE

PRESENCE OF EPNs

1 Sabangan Zucini 3.49 Silt loam +

2 Sabangan Zucini 5.67 Silt loam -

3 Capinitan Cabbage 4.08 Silt loam +

4 Capinitan Cabbage 4.03 Silt loam +

5 Capinitan Cabbage 5.19 Silt loam -

6 Busa Capinitan Potato 5.10 Loam -

7 Busa Capinitan Broccoli 5.90 Silt loam -

8 Busa Capinitan Potato 5.10 Silt loam +

9 Busa Capinitan Broccoli 5.95 Silt loam +

10 Busa Capinitan Potato 5.45 Silt loam -

11 Kamatagan Beans 5.28 Loam +

12 Kamatagan Zucini 6.28 Loam -

13 Pengew Sabangan Zucini 3.63 Silt loam -

Appendix Table 2a. Pearson Chi-Square Test Analysis of Independence for EPN presence and soil Ph (Sabangan, Mountain Province)

SOIL PH PRESENCE OF EPNs

TOTAL

(-) (+)

3 (3.00-3.99) 1 1 2

4 (4.00-4.99) 0 2 2

5 (5.00-5.99) 5 3 8

6 (6.00-6.99) 1 0 1

Total 6 7 13

Pearson chi2 (4) = 3.4435 Pr = 0.328; X2(.05,3)= 7.815 NS- not significant

Appendix Table 2b. Pearson Chi-Square Test Analysis of independence for EPN presence and soil texture (Sabangan, Mountain Province)

SOIL TEXTURE PRESENCE OF EPNs

TOTAL

(-) (+)

Loam 2 1 3

Silt loam 5 5 10

Total 7 6 13

Pearson chi2 (4) = 0.2579 Pr = 0.612; X2(.05,1)= 3.841 S-significant

(34)

Appendix Table 3. Locality, crop, pH, soil texture and presence of EPN in soil samples collected from Bontoc, Mountain Province

SAMPLE

# LOCALITY CROP

AVERAGE SOIL pH

SOIL TEXTURE

PRESENCE OF EPNs

1 Lanao Eggplant 5.66 Silt loam -

2 Lanao Onion 4.605 Sandy loam -

3 Lanao Tomato 4.935 Sandy loam -

4 Lanao Petchay 3.775 Sandy loam -

5 Lanao Camote 4.4 Silt loam -

6 Lanao Beans S 4.205 Silt loam +

7 Lanao Petchay 5.46 Sandy loam -

8 Lanao Petchay 5.195 Sandy loam -

9 Lanao Petchay 5.42 Sandy loam -

10 Lanao Petchay 4.15 Silt loam -

11 Lanao Camote 5.375 Sandy loam -

12 Lanao Beans 4.565 Sandy loam -

13 Lanao Banana 5.8 Sandy loam +

Appendix Table 3a. Pearson Chi-Square Test Analysis of Independence for EPN presence and soil pH (Bontoc, Mountain Province)

SOIL PH PRESENCE OF EPNs

TOTAL

(-) (+)

3 (3.00-3.99) 1 0 1

4 (4.00-4.99) 5 1 6

5 (5.00-5.99) 5 1 6

Total 11 2 13

Pearson chi2 (4) = 0.1970 Pr = 0.906; X2(.05,2)= 5.991 NS- not significant

Appendix Table 3b. Pearson Chi-Square Test Analysis of Independence for EPN presence and soil texture (Bontoc, Mountain Province)

SOIL TEXTURE PRESENCE OF EPNs

TOTAL

(-) (+)

Loam 8 1 9

Silt loam 3 1 4

Total 11 2 13

Pearson chi2 (4) = 0.4104 Pr = 0.522; X2(.05,2)= 3.841 NS-not significant

(35)

Appendix Table 4. Locality, crop, pH, soil texture and presence of EPN in soil samples collected from Sagada, Mountain Province

SAMPLE

# LOCALITY CROP

AVERAGE SOIL pH

SOIL TEXTURE

PRESENCE OF EPNs

1 Sagada Cabbage 4.49 Silt loam -

2 Sagada Onion 5.15 Silt loam -

3 Dugo Sagada Banana 5.04 Silt loam -

4 Batnong Cabbage 4.68 Silt loam -

5 Liang Sagada Pepper 5.17 Silt loam -

6 Liang Sagada Pepper 4.96 Silt loam +

7 Engan Beans 4.17 Silt loam -

8 Engan Beans 4.58 Silt loam -

9 Nalabasan Sagada Cabbage 4.86 Loam -

10 Nalabasan Sagada Cabbage 4.80 Loam -

11 Nalabasan Sagada camote 4.59 Silt loam -

12 Bayuan Cabbage 3.90 Silt loam -

13 Bayuan Petchay 4.67 Silt loam -

14 Bayuan Cabbage 4.23 Silt loam -

15 Bayuan Cabbage 1.88 Silt loam -

16 Malba,Bayuan Pepper 4.84 Silt loam -

17 Malba,Bayuan Cabbage 4.14 Silt loam -

18 Malba,Bayuan Pepper 4.06 Silt loam -

19 Tobeng Cabbage 4.70 Silt loam +

20 Tobeng tegyab Cabbage 4.09 Silt loam -

21 Madongo Beans 4.03 Silt loam +

22 Madongo Beans 4.42 Silt loam -

23 Madongo Cabbage 4.45 Silt loam -

24 Madongo Beans 4.28 Silt loam -

25 Madongo Beans 4.34 Silt loam -

26 Madongo Cabbage 4.19 Silt loam +

27 Madongo Cabbage 4.33 Silt loam -

28 Petaad Ambasing Pepper 3.97 Silt loam -

29 Petaad Ambasing Strawberry 4.15 Silt loam -

30 Petaad Ambasing Strawberry 4.22 Silt loam -

31 Petaad Ambasing Strawberry 4.25 Silt loam -

32 Legleg Ambasing Tomato 5.37 Silt loam -

33 Legleg Ambasing Beans 3.94 Silt loam -

34 Legleg Ambasing Eggplant 4.24 Silt loam -

35 Legleg Ambasing Chinese cabbage 5.53 Loam -

36 Legleg Ambasing Pepper 4.41 Silt loam -

37 Ambasing Beans 4.25 Silt loam -

(36)

Appendix Table 4a. Pearson Chi-Square Test Analysis of Independence for EPN presence and soil pH (Sagada, Mountain Province)

SOIL PH PRESENCE OF EPNs

TOTAL

(-) (+)

1 (1.00-1.99) 1 0 1

3 (3.00-3.99) 3 0 3

4 (4.00-4.99) 24 4 28

5 (5.00-5.99) 5 0 5

Total 33 4 37

Pearson chi2 (4) = 1.4416 Pr = 0.696; X2(.05, 3) = 7.815 S-significant

Appendix Table 4b. Pearson Chi-Square Test Analysis of Independence for EPN presence and soil texture (Sagada, Mountain Province)

SOIL TEXTURE PRESENCE OF EPNs

TOTAL

(-) (+)

Loam 3 0 3

Silt loam 30 4 34

Total 33 4 37

Pearson chi2 (4) = 0.3957 Pr = 0.529; X2(.05, 1) = 3.841 NS- not significant

(37)

Appendix Table 5. Locality, crop, pH, soil texture and presence of EPN in soil samples collected from Besao, Mountain Province

SAMPLE

# LOCALITY CROP

AVERAGE SOIL pH

SOIL TEXTURE

PRESENCE OF EPNS

1 Besao proper Beans 6.43 Loam -

2 Besao proper Beans 5.14 Silt loam -

3 Banao Potato 4.97 Silt loam -

4 Banao Beans 4.51 Silt loam -

5 Banao, site 3 Potato 5.48 Silt loam -

6 Banao Strawberry 4.15 Silt loam -

7 Banao, site 3 Potato 4.84 Silt loam +

8 Banao, site 3 Potato 5.00 Silt loam -

9 Banao Potato 5.44 Silt loam -

10 Banao Citrus 5.56 Loam -

11 Banao, site 3 Potato 4.65 Silt loam +

12 Banao, site 3 Potato 5.12 Silt loam -

13 Banao, site 2 Potato 4.57 Silt loam -

14 Banao, site 2 Cabbage 4.00 Silt loam -

15 Banao, site 2 Potato 4.35 Silt loam +

16 Banao, site 2 Potato 4.36 Silt loam -

17 Banao, site 2 Potato 4.50 Silt loam +

18 Banao, site 2 Cabbage 3.9 Silt loam -

19 Banao, site 2 Potato 4.36 Silt loam +

20 Banao, site 2 Cabbage 4.46 Silt loam +

21 Banao, site 2 Cabbage 4.52 Silt loam -

22 Banao, site 2 Cabbage 3.97 Silt loam -

23 Banao, site 2 Cabbage 4.33 Silt loam -

24 Banao Potato 4.66 Silt loam +

25 Banao, site 1 Cabbage 4.86 Silt loam -

26 Banao, site 1 Petchay 5.71 Loam +

27 Banao, site 1 Cabbage 4.99 Silt loam -

28 Banao Cabbage 5.61 Silt loam -

29 Banao, site 1 Petchay 5.22 Silt loam -

30 Amdakig, site 3 Cabbage 4.31 Silt loam -

31 Amdakig, site 3 Potato 4.75 Silt loam +

32 Amdakig, site 3 Cabbage 4.85 Silt loam -

33 Banguitan Beans 6.94 Loam -

34 Banguitan Garden pea 7.23 Loam +

35 Suquib Pepper 5.77 Silt loam -

36 Suquib Cabbage 5.03 Silt loam -

37 Suquib Pepper 5.36 Silt loam -

38 Suquib Pepper 5.70 Silt loam -

39 Suquib Petchay 4.48 Silt loam +

40 Suquib Camote 5.67 Silt loam -

41 Suquib Cabbage 4.68 Silt loam -

(38)

Appendix Table 1. Continued…

SAMPLE

# LOCALITY CROP

AVERAGE SOIL pH

SOIL TEXTURE

PRESENCE OF EPNs

42 Suquib Cabbage 5.31 Silt loam -

43 Suquib Cabbage 4.73 Silt loam -

44 Suquib Cabbage 4.51 Silt loam -

45 Suquib Pepper 5.31 Silt loam -

Appendix Table 5a. Pearson Chi-Square Test Analysis of Independence for EPN presence and soil pH (Besao, Mountain Province)

SOIL PH PRESENCE OF EPNs

TOTAL

(-) (+)

3 (3.00-3.99) 2 0 2

4 (4.00-4.99) 15 9 24

5 (5.00-5.99) 15 1 16

6 (6.00-6.99) 2 0 2

7 (7.00-7.99) 0 1 1

Total 11 15 45

Pearson chi2 (4) = 9.4677 Pr = 0.050; X2(.05,3)= 9.48 S-significant

Appendix Table 5b. Pearson Chi-Square Test Analysis of Independence for EPN presence and soil texture (Besao, Mountain Province)

SOIL TEXTURE PRESENCE OF EPNs

TOTAL

(-) (+)

Loam 3 2 5

Silt loam 31 9 40

Total 34 1 45

Pearson chi2 (4) = 0.7370 Pr = 0.391; X2(.05, 1) = 3.841 NS- not significant

(39)

Appendix Table 6. T-test for equivalence of EPN presence and soil ph VARIABLE OBSER-

VATION

MEAN STD.

ERR

STD.

DEV.

95%

CONF.

INTERVA L

(-) 5 5.312 2.548094 5.69771

2

-1.762644 12.38664

(+) 5 4.522 2.190145 4.89731

3

1.558817 10.60282 Combined 10 4.917 1.589377 5.02605 1.32158 8.51242

Difference 0.789999

9

3.359988 -

6988691

8.568691

Diff=mean (epn_) – mean (epn) t=0.2351 t (.05, 8) = 1.860 Ho: diff=0 Satterthwaite’s degrees of freedom=7.82343

NS-Not significant

Appendix Table 7. T-test for equivalence of EPN presence and soil texture VARIABLE OBSER-

VATIO N

MEAN STD.

ERR

STD.

DEV.

95%

CONF.

INTERVAL

(-) 7 11.65286 8.502528 22.49557 -1.762644 12.38664 (+) 7 3.118572 2.747365 7.268844 -1.558817 10.60282 Combined 14 7.385714 4.452583 16.66004 1.32158 8.51242 Difference 8.53428

6

8.935378 -10.93 8.568691

Diff=mean (var2) – mean (var3) t=0.9551 t (.05, 12) = 1.782 Ho: ff=0 degrees of freedom=12

NS- Not significant

Appendix Table 8. T-test for equivalence of EPN presence and crops VARIABLE OBSER-

VATIO N

MEAN STD.

ERR

STD.

DEV.

95%

CONF.

INTERVA L

(-) 12 5.41 1.826214 6.326191 1.39053 9.42947

(+) 12 1.77 0.776657

6

2.690421 0.0605882 3.579412 Combined 24 3.59 1.042005 5.10476 1.434449 5.745551

Difference 3.64 1.984504 -

0.4756086

7.755609

Diff=mean (var2) – mean (var3) t=1.8342 t (05, 12) = 1.717 Significant

Pigura

Figure 1. Sampling sites in Bauko, Mt. Province: (A) Buga, Mt. Data, (B) Sintu proper, (C)  Sintu, (D) Monamon
Figure 2. Sampling sites in Sabangan, Mt. Province: (A) Pengew, (B) Capinitan
Figure 3. Sampling sites in Lanao, Bontoc, Mt. Province: (A) site 1, (B) site 2
Figure 4. Sampling sites in Sagada, Mt. Province: (A) Nalabasan, Poblacion, (B)  Madongo, (C) Petaad, Ambasing, (D) Legleg, Ambasing
+7

Mga Sanggunian

NAUUGNAY NA DOKUMENTO

Table 5 shows the moisture content of the meat samples obtained from the rabbits given talinum which has the highest percentage of 77.16 and the meat samples from the rabbits given