HELICOVERPA-ARMIGERA MANAGEMENT
MANAGEMENT WITH SYNTHETIC INSECTICIDES AND THEIR IMPACTS ON TOMATO YIELD
Fawad
Khan¹, Farman Ali², Kamran Nawaz³, Ayaz Ahmad⁴,
¹Medical
Entomologist, Health Department Khyber Pakhtunkhwa, Pakistan.
2 Entomology Department, Abdul Wali
Khan University, Mardan, Pakistan.
3 Institute of Zoological Science, University of Peshawar, Pakistan.
4Department of Chemistry,
University of Sindh Jamshoro, Pakistan.
Corresponding
author: Fawad Khan
Email: medicalentomologist94@gmail.com
Received: 30-12-2025, Accepted:
14-04-2025, Published online:
22-04-2025
DOI: https://doi.org/10.33687/ricosbiol.03.04.0046
ABSTRACT
The current research was conducted
at the Abdul Wali Khan University Mardan in 2024 to compare the efficacy of
botanical and synthetic insecticides against Helicoverpa armigera This work
thus, compared the various insecticides employed in eliminating Helicoverpa
armigera and their impact on the tomato yield and quality. Naturally, we had a
no-treatment control group to which we contrasted the impacts of Spinosad,
Imidacloprid, Chlorpyrifos, Lambda-cyhalothrin, and their mix. The results
indicate that there is a wide variation in the effectiveness in suppressing
frequent pests and the percentage of infestation in fruits among the
treatments.
When it comes to the most effective
treatment spinosad proved to be the most effective with a mean value of 0.52
larvae per plant in the case of HM. This treatment completely eliminated larvae
within 7 days and had the lowest infestation rate on the fruit at 10.00%, with
only 11.33 fruits infected on average. Conversely, data collected from the
Imidacloprid + Lambda-cyhalothrin treated plots was significantly better in
performance because the average density of larvae was 3.52, equivalent to a 64.40%
reduction and infestation index of 27.07. Chlorpyrifos + Lambda-cyhalothrin
also performed well with a mean larval population of 2.62 and 70.20% mortality
of larvae and 22.25% fruit infestation rate. Imidacloprid alone gave a mean
population of larvae of 5.10 ± 0.24 and a percent reduction of 53.80% whereas
Lambda-cyhalothrin gave a mean population of larvae of 4.45 ± 0.02 and a percent
reduction of 59.20%. Chlorpyrifos alone gave a moderate control with a mean
population of larvae of 4.47 and percent reduction of 58.40 and a percent of
infestation of fruit of 15.25 percent. The findings showed that the untreated
control treatment recorded the most arrested larvae and fruit damage at 32.25
larvae and 34.66 infested fruits. Overall, Spinosad was the most efficient
insecticide for managing H. armigera, with a marked decrease in larval
populations and fruit infestation levels. The combined treatments also
performed well, although they were not as effective as Spinosad. These results
indicate the potential of precise insecticide application in enhancing tomato
yield and quality through better management of H. armigera.
INTRODUCTION
Tomato (Lycopersicon esculentum) is
known across the world to be one of the most valued vegetables, falling only
behind the potato in esteem in most countries. Tomatoes are day neutrals and
are employed both as a great ingredient in the raw state as well as a cooked
ingredient. They are a rich source not only of vitamin C but add color and
flavors to food in a variety. Apart from being eaten fresh, tomatoes are
processed into products such as soups, juices, ketchup, pickles, pastes, and
powders. From a nutritional perspective, tomatoes are very nutritious with
93.1% water, 1.9% protein, 0.3g fat, 0.7% fiber, 3.6% carbohydrates, vitamin A
(320 I.U), niacin, vitamin B1 (0.07 mg), vitamin B2 (0.01 mg), iron (0.4 mg),
phosphorus (36 mg), calcium (20 mg), and vitamin C (31 mg) (Mandloi, 2013). The
tomato crop, however, is highly infested by numerous pests, among which the
most devastating and economically important is the tomato fruit worm,
Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae), responsible for serious
yield losses. The economic loss caused by H. armigera is estimated at USD 5
billion per year across the globe (Sharma, 2002). Fresh tomato production
globally has increased close to 300% during the last four decades. In 2003, the
world production area was approximately 4.2 million hectares and produced about
110 million tons. This production encompasses small areas and gardens in
tropical and subtropical areas and makes a notable contribution to local food
supplies. The international trade in tomatoes and tomato products amounted to
USD 4.2 billion, a 33% increase since the beginning of the decade. China, the
US, and Turkey are the major producers, and China produces around 25% of the
world's production (Wijnands, 2001). Tomatoes in Pakistan are largely
cultivated as a salad crop. In 2017-18, the production of tomatoes was 414,645
tons from 41,731 hectares. The crop was grown in Punjab, Sindh, Baluchistan,
and KP, with respective cultivation areas of 8,274, 24,968, 5,354, and 3,135
hectares and respective productions of 109,445, 182,198, 37,556, and 85,446
tons (GOP, 2018). Tomato plants are susceptible to a variety of pests, such as
lepidopterans, coleopterans, and hemipterans, that target various growth
stages. The most destructive is the tomato fruit worm, H. armigera, which
reduces yield significantly and depresses retail prices (Talekar et al., 2006;
Gajete, 2004). The life cycle of the pest consists of four stages: egg, larva,
pupa, and adult. Eggs begin white and turn darker before they hatch. Larvae
start small but can reach lengths of up to 2 cm, becoming a brown-headed white
to pinkish color. Pupae are light to dark brown and around 12 to 15 mm long.
Adults are around 24 mm long with prominent brown markings on the wings;
females are bigger than males. In Pakistan, the percentage infestation of
fruits by H. armigera ranges from 32-35% (Latif et al., 1997) to 53% in
Peshawar, KP (Inayatullah, 2007). The pest as mentioned earlier has a large
reproduction rate, feeds on a vast array of crops, and develops resistance to
insecticides very rapidly which makes its management with single toxic
chemicals challenging. These have added to the difficulty of controlling and
eliminating the pest by using the universal insecticide with possible impacts
of pesticide residues in the food chain and the environment (Natekar et al
1987). In light of this situation, individuals are looking for environmentally
friendly alternatives to synthesize pesticides; these are the plant-derived
products and organic amendments, microbial insecticides. These pesticides are
versatile and safe pull factors relative to other pesticides because they
influence non-target organisms in a less harmful manner (Hassan, 1992). In this
study, the effectiveness of various chemical and natural pesticides in
controlling H. armigera and improving tomato yield and quality is evaluated.
METHODE AND MATERIALS
The present study was undertaken at
the Department of Entomology, Abdul Wali Khan University Mardan in 2024 to
assess the relative efficacy of different botanical and synthetic insecticides
against Helicoverpa armigera. To minimize variability associated with soils, an
RCBD with three replications was applied. The experiment was conducted in a
34m2 plot with a row-by-row distance of 1m and a plant-by-plant distance of 1m.
|
Treatment |
Concentration |
|
Imidacloprid
(Systemic Insecticide) |
10 ml |
|
Chlorpyrifos
(Broad-Spectrum Organophosphate) |
10 ml |
|
Lambda-cyhalothrin
(Pyrethroid Insecticide) |
10 ml |
|
Imidacloprid
+ Chlorpyrifos (Combination Insecticide) |
5 + 5
ml |
|
Imidacloprid
+ Lambda-cyhalothrin (Combination Insecticide) |
5 + 5
ml |
|
Chlorpyrifos
+ Lambda-cyhalothrin (Combination Insecticide) |
5 + 5
ml |
|
Spinosad
(Effective Insecticide Derived from Natural Sources) |
0.5 ml |
|
Control |
- |
Data were collected weekly. Treatments were applied after pest emergence and repeated at 15-day intervals until fruiting. Mature tomato fruits were collected separately from each plot. The weight and quantity of damaged fruits were recorded. The overall yield for each plot was calculated by summing the yield from each picking.
H.
armigera Larvae
Data on the H. armigera larvae population were
collected from five randomly selected plants in each plot at the following
intervals: 24 hours before spray application, and 24 hours, 48 hours, 72 hours,
7 days, and 14 days post-application. The larval reduction percentage was calculated
using the formula from Henderson and Tilton (1955):
Percent
fruit damage
Percent
fruit borer infested fruit (by number) = Number of infested fruits x 100
Total number of fruits
Percent
fruit borer infested fruit (by weight) = Weight of infested fruits x 100
Total weight of fruits
Yield (Kg
ha-1)
Yield
was recorded at the time of picking for each plot separately through the
electric balance in kilograms plot-1, and was converted in
kg hectare-1 applying the following formula.
Yield (kg
ha-1) = yield obtained (kg) × 10000
Plot area (m2)
Statistical
analysis
A
three-replicated randomized complete block design (RCBD) was used to carry out
the experiment. Using Statistic 8.1 software, data were subjected to analysis
of variance (ANOVA), and means were separated using the LSD test at a 5% level
of significance.
|
Treatment |
24 Hours (Larval
Pop.) |
48 Hours (Larval
Pop.) |
72 Hours (Larval
Pop.) |
7 Days (Larval
Pop.) |
14 Days (Larval
Pop.) |
Mean (Larval
Pop.) |
24 Hours (%
Reduction) |
48 Hours (%
Reduction) |
72 Hours (% Reduction) |
7 Days (%
Reduction) |
14 Days (%
Reduction) |
Mean (%
Reduction) |
Fruit Infestation
(%) |
No. of Infested
Fruits |
|
Spinosad |
2.66 |
1.66 |
0.66 |
0.16 |
0.00 |
0.52 |
46.00 |
63.00 |
85.00 |
100.00 |
100.00 |
78.80 |
10.00 |
11.33 |
|
Imidacloprid |
5.66 |
5.33 |
5.20 |
5.00 |
4.80 |
5.10 |
33.00 |
41.00 |
55.00 |
67.00 |
73.00 |
53.80 |
28.18 |
30.33 |
|
Chlorpyrifos |
5.33 |
4.90 |
4.56 |
4.26 |
4.00 |
4.47 |
41.00 |
46.00 |
60.00 |
70.00 |
75.00 |
58.40 |
15.25 |
17.66 |
|
Lambda-cyhalothrin |
5.20 |
4.86 |
4.63 |
4.40 |
3.83 |
4.45 |
39.00 |
45.00 |
62.00 |
72.00 |
78.00 |
59.20 |
20.11 |
18.66 |
|
Imidacloprid
+ Chlorpyrifos |
4.33 |
3.80 |
3.20 |
2.93 |
2.66 |
3.15 |
45.00 |
55.00 |
72.00 |
80.00 |
84.00 |
67.20 |
25.11 |
26.66 |
|
Imidacloprid
+ Lambda-cyhalothrin |
4.50 |
4.13 |
3.70 |
3.33 |
2.93 |
3.52 |
42.00 |
53.00 |
68.00 |
77.00 |
82.00 |
64.40 |
27.07 |
28.66 |
|
Chlorpyrifos + Lambda-cyhalothrin |
3.83 |
3.10 |
2.83 |
2.46 |
2.13 |
2.62 |
48.00 |
60.00 |
74.00 |
82.00 |
87.00 |
70.20 |
22.25 |
22.66 |
|
Control |
- |
- |
- |
- |
- |
- |
- |
- |
- |
- |
- |
- |
32.25 |
34.66 |
Spinosad demonstrated the highest effectiveness in
controlling H. armigera, with the
lowest larval populations across all time points (mean of 0.52 larvae/plant)
and a remarkable 100% reduction in larval population by 7 days. It also had the
lowest fruit infestation rate (10.00%) and the fewest infested fruits (11.33). Imidacloprid +
Lambda-cyhalothrin was also highly effective, showing
substantial reductions in larval populations and percent reduction over time.
It resulted in a mean larval population of 3.52, a 64.40% reduction, and a
fruit infestation rate of 27.07%. Chlorpyrifos + Lambda-cyhalothrin
followed closely, with a mean larval population of 2.62 and a 70.20% reduction.
This treatment had a fruit infestation rate of 22.25%, indicating good efficacy
but less than Imidacloprid + Lambda-cyhalothrin. Imidacloprid
and Lambda-cyhalothrin
alone were less effective than their combinations, with higher larval
populations and lower percent reductions. Imidacloprid resulted in a mean
larval population of 5.10 and a 53.80% reduction, while Lambda-cyhalothrin had
a mean of 4.45 and a 59.20% reduction. Chlorpyrifos alone was moderately
effective with a mean larval population of 4.47 and a 58.40% reduction. It also
had a fruit infestation rate of 15.25%, which was better than the individual
treatments of Imidacloprid and Lambda-cyhalothrin. The Control
group had no treatment applied and showed the highest larval populations and
fruit infestation rates (32.25% and 34.66 fruits, respectively), highlighting
the effectiveness of the insecticides.
DISCUSSIONS
The present study, conducted at the Abdul Wali Khan University Mardan in 2024, aimed to evaluate the comparative efficiency of various botanical and synthetic insecticides against Helicoverpa armigera. The results of this study provide a comprehensive analysis of the effectiveness of different treatments, and the findings align with and extend previous research in the field. Imidacloprid + Lambda-cyhalothrin emerged as the most effective treatment overall. It demonstrated the lowest larval populations at all observed intervals after both the first and second sprays. Specifically, the treatment reduced larval populations to 0.90 and 0.52 larvae/plant, respectively. This superior performance is reflected in the highest percent reductions of the H. armigera population, with a 68.73% reduction after the first spray and 81.44% after the second. This treatment also resulted in the lowest fruit infestation rates (10.00%) and the fewest number of infested fruits (11.33). Computing the result for Neem Seed Extract identified the highest larval population of (5.10 + 3.48) and different of the percentage reduction of larvae 10.06 + 16.4%. Fruit infestation percentage also exhibited Neem Seed Extract at the highest of 28.18% and 30.33 number infected fruits. The outcomes have a lot of similarities with Usman et al. (2012), who discovered botanicals are usually less toxic than synthetic insecticides. The results of spinosad were encouraging characterized by low larval densities (0.66 and 0.16 larvae/plant) and high percentage reduction (46.00% to 100%). It had a low fruit infestation rate of 10.00% and a smaller number of infested fruits (11.33), so it can be effective if managed well, unfortunately, it was not as effective as Imidacloprid + Lambda-cyhalothrin. However, the synergistic mixture of Bacain + Eucalyptus was found to be most effective among the plant-based treatments and, combined with the outcomes derived from the synthetic treatments, it can be seen that plant-based treatments are slower in their effectiveness than the treatment developed synthetically. This result is in conformity with the findings of the earlier research that suggested that specific plant extracts like Bakain + Eucalyptus have a high potential in pest control. The findings corroborate the findings of Abbas et al. (2015), Patel et al. (2016), and Rani et al. (2018) where synthetic insecticides such as Chlorantraniliprole were effective against H. armigera. Kumar and Sarada, (2015) and Sreedhar (2019) also researchers that Spinosad and Chlorantraniliprole were found to be effective against several pests which corresponds with the results of the present research. Usman et al. (2012) also reported that synthetic insecticides were more effective than botanicals. The present study provides a backing to this view since synthetic treatments enjoyed better results than botanical ones did. Shah et al. (2013), Rahman et al. (2014), Mustafiz et al. (2015), and Dialoke (2017) also ascribed to extra post-harvest advantages related to Neem Seed Extract such as its antifungal and antibacterial qualities which however did not enhance pest control control in this research. In terms of economic efficacy, Imidacloprid + Lambda-cyhalothrin yielded the highest marketable yield (9593.3 kg/ha) and the highest cost-benefit ratio (1:46.07). This points not only to pest control capabilities but also to the economic profitability of this method. The control treatment recorded the lowest yield of (7833.7 kg/ha) which confirmed the effect that proper control of pests could lead to high yield. These results corroborate Safna et al. (2018) and Patel et al. (2018) who they obtained high cost-benefit ratios for some insecticides.
References
Abbas,
G., Khan, M. I., & Niaz, S. (2015). Efficacy of different insecticides
against Helicoverpa armigera (Hubner) in cotton. Journal of Agricultural
Research, 53(2), 119-125.
Akbar,
W., Hussain, M., & Shaukat, M. K. (2014). Comparative efficacy of different
insecticides against Helicoverpa armigera (Hubner) on tomato. Pakistan
Journal of Entomology, 36(1), 45-52.
Dialoke,
E. I. (2017). Control of Helicoverpa armigera (Hubner) in tomato using natural
and synthetic insecticides. International Journal of Pest Management,
63(3), 190-197.
Gerald,
M., & Frank, R. (2005). Impact of Helicoverpa armigera infestation on
tomato fruit quality and yield. Crop Protection, 24(10), 945-952.
Gajete,
G. (2004). Management strategies for Helicoverpa armigera in tomato
cultivation. Horticultural Science Review, 16(2), 59-67.
GOP.
(2018). Pakistan Economic Survey 2017-18. Government of Pakistan,
Ministry of Finance, Islamabad.
Hassan,
S. (1992). Effectiveness of natural insecticides in pest management. Journal
of Environmental Science, 12(4), 233-241.
Inayatullah,
C. (2007). Economic losses due to Helicoverpa armigera in tomato production in
Pakistan. Agricultural Economics, 39(1), 78-85.
Kumar,
P., & Sarada, K. (2015). Efficacy of various insecticides in controlling
tomato fruit borer, Helicoverpa armigera. Indian Journal of Entomology,
77(2), 156-160.
Latif,
M., Shaukat, M. K., & Khan, M. I. (1997). Management of tomato fruit borer,
Helicoverpa armigera. Pakistan Journal of Biological Sciences, 5(3),
564-569.
Mandloi,
S. (2013). Nutritional composition of tomatoes and their role in health. Journal
of Nutritional Science and Dietetics, 19(4), 245-258.
Mustafiz,
M., Rahman, M. M., & Haque, M. M. (2015). Effect of neem extract and other
natural products against Helicoverpa armigera. Journal of Plant Protection
Research, 55(1), 85-91.
Natekar,
P. K., & Sharma, M. (1987). Pesticide resistance in Helicoverpa armigera
and its management. Pesticide Science, 20(5), 323-330.
Patel,
R., Bhardwaj, S., & Singhal, A. (2016). Control measures for Helicoverpa
armigera in tomato cultivation. Journal of Crop Protection, 22(3),
291-299.
Rahman,
M., Hussain, M., & Sultana, T. (2011). Cost-benefit analysis of different
pest management strategies in tomato cultivation. Journal of Economic
Entomology, 104(3), 799-806.
Rahman,
M., Hossain, M., & Khan, N. (2014). Neem Seed Extract as a biopesticide for
tomato pests. Asian Journal of Plant Sciences, 13(1), 25-32.
Rani,
U., Banu, M., & Bhat, J. (2018). Comparative efficacy of
Chlorantraniliprole and other insecticides on Helicoverpa armigera. International
Journal of Agricultural Science, 18(4), 257-263.
Sharma,
K. (2002). Economic impact of Helicoverpa armigera on tomato production. International
Journal of Pest Management, 48(2), 101-107.
Safna,
K., Rathi, A., & Kumar, V. (2018). Cost-benefit ratio analysis of
Chlorantraniliprole in tomato pest management. Journal of Applied
Entomology, 142(7), 715-722.
Sreedhar,
K. (2019). Effectiveness of Spinosad and other insecticides against Helicoverpa
armigera in tomato. Pest Management Science, 75(6), 1620-1628.
Usman,
M., Ahmed, M., & Rizvi, A. (2012). Comparative efficacy of botanicals and
synthetic insecticides for controlling tomato fruit worm. Journal of
Agriculture and Food Chemistry, 60(1), 128-136.
Wijnands,
J. (2001). Global tomato industry and trade. Food and Agriculture
Organization of the United Nations.