Impaginato 71 Adv. Hort. Sci., 2018 32(1): 71-78 DOI: 10.13128/ahs-21208 Phytochemical composition and insecticidal potentials of some plant aqueous extracts in suppressing Podagrica spp. (Coleoptera: Chrysomelidae) infestation on Okra (Abelmoschus esculentus L. Moench) J.M. Adesina1, 2 (*), Y. Rajashekar 2 1 Department of Crop, Soil and Pest Management Technology, Rufus Giwa Polytechnic, P.M.B. 1019, Owo, Ondo State, Nigeria. 2 Insect Chemical Ecology Laboratory, Institute of Bioresources and Sustainable Development, Department of Biotechnology, Government of India, Takyelpat, Imphal 795001, Manipur, India. Key words: Bryscocarpus coccineus, Calotrophus procera, Canarium schwein- furthii, insecticidal activity, phytochemical screening. Abstract: Foliar application of 25% w/v crude aqueous extracts of Calotrophus pro- cera (Aiton) W.T. Aiton, Canarium schweinfurthii (Engl.) and Bryscocarpus coc- cineus (Schum. & Thonn.) were evaluated for their insecticidal activity in reducing Podagrica infestation on okra. Results showed that the plants extracts significantly suppress Podagrica spp. infestation and protect okra plant from severe leaves defoliation, with C. schweinfurthii (21.67 and 20.14) and B. coccineus (23.07 and 24.55) showing promising insecticidal activity for both cropping seasons. The yield attributes from okra sprayed with Lambda cyhalothrin did not differ significantly compared to those sprayed with botanical insecticide despite having highest yield attributes. Qualitative phytochemical screening revealed the presence of Triterpenoids, Steroids, Flavonoids, Phlobatanins, Saponins, Tannins, Cardiac gly- coside and Anthraquinones. Alkaloids and Anthraquinones were not detected in C. procera and C. schweinfurthii while Triterpenoids and Phlobatanins were absent in C. schweinfurthii. The presence of these phytochemicals indicates that the plants possess insecticidal properties responsible for significant reduction in Podagrica spp. infestation, severity of leaves damaged and improved okra yields. Performance of the treatments is rated in the following order: Lambda cyhalothrin > B. coccineus > C. schweinfurthii > C. procera, with B. coccineus and C. schwein- furthii having similar treatment means in all the parameters evaluated. In light of the foregoing, crude extracts of B. coccineus and C. schweinfurthii could be utilized as suitable alternative to synthetic insecticide in sustainable okra production. 1. Introduction Okra (Abelmoschus esculentus L. Moench) is an important fruit veg- (*) Corresponding author: moboladesina@yahoo.com Citation: ADESINA J.M., RAJASHEKAR Y., 2018 - Phytochemical composition and insecticidal potentials of some plant aqueous extracts in sup- pressing Podagrica spp. (Coleoptera: Chysomelidae) infestation on Okra (Abelmoschus esculentus L. Moench) - Adv. Hort. Sci., 32(1): 71- 78 Copyright: © 2018 Adesina J.M., Rajashekar Y. This is an open access, peer reviewed article published by Firenze University Press (http://www.fupress.net/index.php/ahs/) and distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Data Availability Statement: All relevant data are within the paper and its Supporting Information files. Competing Interests: The authors declare no competing interests. Received for publication 8 September 2017 Accepted for publication 12 January 2018 AHS Advances in Horticultural Science Adv. Hort. Sci., 2018 32(1): 71-78 72 etable crop in the diets of most people in the tropics and subtropical countries. It is grown mainly for its freshly immature pods and ranks fourth worldwide after pepper, tomato and onion on the basis of land area, production and value. Despite the great demand for okra due to its nutri- tional and economic importance, okra production is being hampered by array of insect pest infestation r e s u l t i n g i n p o o r y i e l d a n d l o w m a r k e t v a l u e . D i f f e r e n t g r o w t h s t a g e s o f o k r a a r e g e n e r a l l y attacked by different insect pests (Adesina and Afolabi, 2014; Kedar et al., 2014) and Podagrica species (Coleoptera: Chrysomelidae) is one of the most prevalent and damaging insect pests consid- ered as major constraint to cultivation of okra which defoliate or damage the plant leaves and flowers; thereby results in reduction of the photosynthetic capability of the crop (Odebiyi, 1980). The insects equally act as vectors in transmitting mosaic viral dis- eases and ultimately reduce yield (Fasunwon and Banjo, 2010), mainly if control measures are not undertaken. Important yield losses of 20-50% are reported in Nigerian and Ghana (Obeng-Ofori and Sackey, 2003; Ahmed et al., 2007; Fajinmi and Fajinmi, 2010). Currently, synthetic insecticide is being used across the globe to control agriculturally important insect pests due to their quick action and lasting effect (Alao et al., 2011). The failure of synthetic insecti- cides to ensure total insect pest control due to devel- opment of resistant and resurgence and couple with increasing concern over environmental pollution, car- cinogenic effect and destruction of beneficiary insects (Isman, 2008), level of pesticide residues in food had compelled the scientific community to explore the abandoned and neglected traditional and indigenous products that are cheap, environmental safe and easily biodegradable products as alterna- tives to synthetic insecticides for tackling agricultural insect pests (Antonio, 2009; Alao et al., 2011; Aetiba and Osekre, 2016). Presently, in many parts of the world, attention has been focused on the utilization of plant products that possess both medicinal and aromatic properties which are abound in various agro-ecological zones of the world as novel chemotherapeutants in plant pro- tection (Dubey et al., 2010). The popularity of botani- cal pesticides is once again increasing and some plant products either in crude form or by processing into different formulations are being used globally as green pesticides (Dubey et al., 2008). The shortcomings associated with the use of syn- thetic chemicals, necessitated the idea of developing effective, cheap and easily biodegradable alternative products. Therefore, this study aims to screen and r e p o r t t h e e f f i c a c y o f a q u e o u s e x t r a c t s o f Calotrophus procera (Ait.) Ait., Canarium schwein- furthii (Engl.) and Bryscocarpus coccineus (Shum and Thonn.) in suppressing flea beetles Podagrica spp. (Coleoptera: Chrysomelidae) infestation on okra. 2. Materials and Methods Experimental location, designs and treatments The study was carried out on 168 m2 area of land manually cleared and prepared at the Teaching and Research Farm, Rufus Giwa Polytechnic (RUGIPO), Owo, Ondo State located in South Western Nigeria and lies on latitude 7° 12’ N and longitude 7° 35’ E. T h e e x p e r i m e n t w a s l a i d o u t i n a R a n d o m i z e d Complete Block Design (RCBD) with three replica- tions. The experimental land was divided into 4 blocks of 4x4 m to produce a total of 12 plots. The plot size was 2x1.5 m with 0.5 m between plots and 1x1 m between blocks to prevent pesticide drift and inter-plot interference, respectively. An early maturity okra cultivar (NH-47) obtained from Ondo state Agricultural Development Project (ADP), Akure, Ondo State, Nigeria was sown with two to three seeds per hole at a depth of 2-3 cm and spaced 50x60 cm and later thinned to one plant per stand. Weeding was carried out manually as at when due to ensure clean plots free from weed competi- tion. The treatments applied were 25% w/v B. coccineus, C. schweinfurthii, C. procera and 0.8 L/ha synthetic i n s e c t i c i d e ( L a m b d a c y h a l o t h r i n ) a s c o n t r o l . Application of treatments commenced four weeks after planting (WAP) with a 2-litre capacity hand-held sprayer. The spraying was carried out weekly till fruit- ing early in the morning to avoid photo decomposi- tion and drifting of the extracts. Synthetic insecticide was applied every two weeks. Collection and preparation of plant extracts Leaves of B. coccineus and C. schweinfurthii were collected from Owo, Ondo state, Nigeria and C. procera were collected from Ogbagi Akoko Ondo State, Nigeria (7° 35’ N, 5° 43’ E) at full blooming and 25 kg were weighed separately using electronic bal- ance (Table 1). Thereafter, the weighed plants were washed with water to remove dirt or other contami- nants and each of the plant materials was pounded separately in a mortar into a fine soft paste form. The Adesina and Rajashekar - Plant aqueous extracts against Podagrica spp. 73 paste (crushed plant leaves) was then put into a 10- litre plastic bucket and the appropriate volume of distilled water added to make a 25% w/v crude aque- ous extract solution (25% w/v represents an extract made with 25 g of crushed plant leaves per every 100 ml of water). The pastes were soaked overnight (approximately 14 hours) in a covered bucket with occasional stirring and filtered using muslin cloth with the filtrates stored in a 10 L keg in a cool dry place till use. Phytochemical screening The qualitative phytochemical tests were per- formed on the crude aqueous extract to detect the presence of bioactive secondary metabolites in test- ed plant materials using standard laboratory meth- ods following the procedure described by Odebiyi and Sofowora, 1978; Sofowora, 1982; Williamson et al., 1996; Banso and Ngbede, 2006; Ngbede et al., 2008. Data collection and statistical analysis All data were collected from five plants randomly tagged per treatment in the two middle rows of each plot. Leaves damage index was determined by visual counting of the number of holes caused by the insect feeding activities. While insect count for estimation of the population densities of P. uniformis and P. sjostedti was made 4 WAP between the hours 6-7 AM when the insects are still inactive through visual counting. The fruits were harvested two months after planting (MAP), when the fruits were still fresh at the interval of 4 days. Weighing balance was used to determine the weight of the fruits and the fruits length measured using ruler. Data collected were analyzed by analysis of variance (ANOVA) using Gester Version 1.2, insect count were subjected to square root (y =√) transformation before analysis to normalize the data. Significant treatment means were compared using Tukey test at 5% probability. 3. Results Podagrica spp. population before application of some plant aqueous extracts Table 2 shows Podagrica spp. population on okra before the application of the aqueous plant extracts treatments. The results showed that the insect popu- lations were not significantly different. The popula- tion ranges between 4.07-4.93/plant for 2015 crop- ping season and 4.10-4.98/plant for 2016 cropping season. Toxicity effect of some plant aqueous extracts in sup- pressing Podagrica spp. infestation The utilization of plant aqueous extracts to sup- press Podagrica spp. infestation on okra was present- ed in Tables 3 and 4 for 2015 and 2016 cropping sea- son, respectively. Application of the various treat- Scientific name Common name Family Part used Calotropis procera Giant swallow wort or Milkweed Asclepiadaceae leaves Canarium schweinfurthii African elemi or canarium Burseraceae leaves Byrsocarpus coccineus Short-pod Connaraceae leaves Table 1 - Plant materials used for the experiment Table 2 - Podagrica spp. population before application of some plant aqueous extracts Treatments Insect population 2015 2016 C. procera 4.07±0.77 a 4.98±0.15 a C. schweinfurthii 4.08±0.66 a 4.46±0.34 a B. coccineus 4.27±0.38 a 4.10±0.07 a Lambda cyhalothrin 4.93±0.66 a 4.47±0.28 a Treatments with the same letter in column are not statistically significant different from each other. Treatments 4 WAP 5 WAP 6 WAP 7 WAP 8 WAP 9 WAP 3 DAS 7 DAS 3 DAS 7 DAS 3 DAS 7 DAS 3 DAS 7 DAS 3 DAS 7 DAS 3 DAS 7 DAS C. procera 2.93±1.86 a 0.33±0.31 ab 0.80±0.60 ab 0.87±1.17 a 1.80±1.51 a 3.27±1.36 b 1.33±1.03 a 0.67±0.12 a 0.20±0.20 b 0.60±0.35 a 0.33±0.31 a 0.80±0.31 ab C. schweinfurthii 1.13±1.14 ab 0.07±0.12 c 0.27±0.23 c 0.07±0.12 b 0.37±0.35 b 1.13±0.70 a 0.27±0.35 ab 0.20±0.35 a 0.00 0.53±0.61 a 0.18±0.12 a 0.73±0.51 ab B. coccineus 1.40±1.22 ab 0.6±0.87 a 1.0±1.40 a 0.40±0.53 a 0.22±0.06 b 0.47±0.53 a 0.4±0.69 ab 0.80±1.22 a 0.82±1.05 a 0.6±0.53 a 0.8±1.22 a 0.93±0.52 a Lambda cyhalothrin 0.13±0.23 c 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00a 0.00 Table 3 - Toxicity effect some plant aqueous extracts in suppressing Podagrica spp. infestation 2015 WAP = Weeks after planting; DAS = Days after spray. Treatments with the same letters in columns are not statistically significant different from each other. Adv. Hort. Sci., 2018 32(1): 71-78 74 ments resulted in significant reduction in the insect population, while synthetic insecticides completely suppressed the insect pest infestation. The results clearly indicate that insect population reduced in rela- tion to the number of spraying regimes, with the exception of okra plants sprayed with C. procera aque- ous extract, which slightly increased or resurgence at 6 WAP for both seasons and 3 days after spraying (DAS) at 7 WAP in 2015 cropping season only. In 2015 non- significant difference was observed at 3 DAS and 7 DAS in all the treatments at 7, 8 and 9 WAP, while in 2016 non-significant difference was recorded 7 DAS at 6, 8 and 9 WAP in 2016 cropping season, respectively. The insecticidal activity of the aqueous plant extracts treatments is rated in the following decreas- ing order: B. coccineus > C. schweinfurthii > C. pro- cera, with B. coccineus and C. schweinfurthii having similar treatment means which is not significantly dif- ferent in most instances but significantly differ com- pared to C. procera in both seasons. Toxicity effect of some plant aqueous extracts on okra yield attributes The yield of okra plant in response to various plant aqueous extracts evaluated in reducing Podagrica spp. infestation was presented in Table 5. From the results, fruit weight and fruit diameter were not sig- nificantly different in both cropping seasons for all t h e t r e a t m e n t s s p r a y e d o n t h e o k r a a g a i n s t Podagrica spp. infestation. Also non-significant dif- ference equally observed between okra plants sprayed with B. coccineus and C. schweinfurthii com- pared to Lambda cyhalothrin for number of harvest- ed fruit and fruit lengths for both seasons except for C. schweinfurthii in 2015 season. Although, there was significant difference in the number of harvest- ed fruits and fruit lengths between okra sprayed with B . c o c c i n e u s , C . s c h w e i n f u r t h i i a n d L a m b d a cyhalothrin compared to C. procera in both seasons. The yield attribute performance of the treatments is rated in the following decreasing order: Lambda cyhalothrin > B. coccineus > C. schweinfurthii > C. procera, with B. coccineus and C. schweinfurthii hav- ing similar treatment means. Effects of plants aqueous extracts on severity of leaves damage on Okra by Podagrica spp. The utilization of plants aqueous extract on severity of leaves damage on Okra (A. esculentus L.) by Podagrica spp. was presented in Table 6. Significant Table 5 - Toxicity effect some plant aqueous extracts okra yield attributes Treatments 4 WAP 5 WAP 6 WAP 7WAP 8 WAP 9 WAP 3 DAS 7 DAS 3 DAS 7 DAS 3 DAS 7 DAS 3 DAS 7 DAS 3 DAS 7 DAS 3 DAS 7 DAS C. procera 2.05±0.62 a 0.73±0.31 a 0.98±0.56 a 0.53±1.04 a 1.18±1.51 a 1.02±0.16 a 0.88±1.06 a 0.63±0.14 b 0.42±0.20 b 0.6±0.35 a 0.55±0.24 a 0.56±0.31 a C. schweinfurthii 1.89±0.14 ab 0.28±1.52 b 0.67±0.23 a 0.18±0.32 a 0.37±0.35 ab 0.63±1.08 a 0.41±0.05 ab 0.4±0.33 a 0.20±0.07 b 0.53±0.61 a 0.17±0.16 b 0.41±1.61 a B. coccineus 1.44±0.21 ab 0.92±0.87 a 0.82±1.03 a 0.46±1.07 a 0.08±0.11 b 0.82±0.12 a 0.2±0.09 ab 0.87±0.22 a 1.0±0.35 a 0.6±0.53 a 0.46±1.42 a 0.57±0.25 a Lambda cyhalothrin 0.10±0.23 c 0.22±1.61 b 0.00 0.00 0.00 0.00 0.00 0.00a 0.00 12:00 0.00 0.00 WAP = Weeks after Planting; DAS = Days after spray. Treatments with the same letters in columns are not statistically significant different from each other. Table 4 - Toxicity effect some plant aqueous extracts in suppressing Podagrica spp. infestation 2016 Parameters C. procera C. schweinfurthii B. coccineus Lambda cyhalothrin 2015 2016 2015 2016 2015 2016 2015 2016 Number of pod 3.75±1.13 b 3.98 ±0.19 b 4.69±1.59 a 4.51±1.79 a 4.75±1.79 a 4.93±2.41 a 5.12±0.84 a 5.45±1.79 a Fruit length 3.02±0.88 ab 3.47±1.66 ab 3.93±2.71 ab 4.00±1.34 a 4.12±1.76 a 4.70±0.28 a 4.83±2.02 a 4.67±1.17 a Fruit weight 0.08±0.06 a 0.05±0.02 a 0.05±0.03 a 0.09±0.11 a 0.05±0.06 a 0.07±0.12 a 0.04±0.03 a 0.06±0.02 a Diameter 5.51±1.89 a 4.80±0.43 a 4.9±1.45 a 4.64±0.93 a 4.44±1.72 a 4.03±1.06 a 4.72±0.69 a 4.46±0.82 a Severity of leaf damage C. procera C. schweinfurthii B. coccineus Lambda cyhalothrin 2015 2016 2015 2016 2015 2016 2015 2016 4 WAP 3.47±1.08 e 4.51±0.71 e 4.73±0.43 e 4.02±0.66 b 3.40 ±1.83 c 3.27±1.10 d 1.67±0.76 a 1.44 ±0.83 a 5 WAP 6.27±0.73 e 8.12±2.46 e 5.82±1.18 e 6.83±0.37 b 4.00±1.95 c 4.17±1.38 d 3.20 ±1.51 a 4.27 ±0.73 a 6 WAP 12.23±1.09 d 12. 85±2.03 d 9.50±1.76 d 8.91±1.92 b 10.53±1.68 b 11.48±2.06 c 4.07 ±0.69 a 4.23 ±1.09 a 7 WAP 19.93±1.93 c 20.14±1.17 c 11.97±0.86 c 13.25±1.81 ab 16.27 ±2.68 ab 17.04±1.39 b 4.07 ±0.39 a 4.93 ±2.93 a 8 WAP 29.60±1.55 b 26.92±2.41 b 15.53±1.78 b 17.09±2.01 a 20.67±2.61 a 19.85±2.14 ab 4.80 ±1.70 a 5.60 ±1.55 a 9 WAP 32.20±0.66 a 33.32±1.82 a 21.67±2.90 a 20.14±1.26 a 23.07±1.32 a 24.55±2.82 a 5.20 ±1.30 a 6.33 ±1.75 a Table 6 - Effects of plants aqueous extracts on severity of leaves damage on Okra by Podagrica spp. Treatments with the same letters in columns are not statistically significant different from each other. Treatments with the same letters in columns are not statistically significant different from each other. Adesina and Rajashekar - Plant aqueous extracts against Podagrica spp. 75 difference was not recorded between okra plant sprayed with the extracts at 4, 5, 6, 8 and 9 WAP. However, there was significant difference in the severity of leaves recorded at 7 WAP. Significant dif- ference was also recorded between C. procera and chemical insect controlled okra but C. schweinfurthii and B. coccineus were not statistically significant from each other. The highest severity was recorded at 9 WAP followed by 7 WAP which could be due to lack of rainfall in these periods. Severity of leaves damage by Podagrica spp. is presented in Table 6. The least percentage leaves defoliation was observed from the plants treated with synthetic insecticide and C. procera treated plant recorded highest percentage of defoliation among the botanical insecticides. C. schweinfurthii and B. coccineus showed significantly promising e f f e c t i n r e d u c i n g s e v e r i t y o f l e a v e s d a m a g e . However, all botanical treated okra plants prevented the leaves from being severely defoliated as all the plants suffered below 33.32% defoliation at 9 WAP. In general term, leaves damage increased with the increasing age of okra plants. Phytochemical screening The result of phytochemical screening of crude leaf extracts revealed the presence of Triterpenoids, S t e r o i d s , F l a v o n o i d s , P h l o b a t a n i n s , S a p o n i n s , Tannins, Cardiac glycoside and Anthraquinones in the plants (Table 7). Alkaloids and Anthraquinones were not detected in both C. procera and C. schweinfurthii while Triterpenoids and Phlobatanins were absent in C. schweinfurthii. The presence of these bioactive compounds in the plant materials is an indication that it may have some insecticidal potential against agriculturally important insect pest. 4. Discussion and Conclusions Plants are rich sources of natural substances that can be utilized in the development of environmental- ly safe methods for insect pests control as veritable alternative to synthetic insecticide (Sadek, 2003). Moreover, growing awareness of health and environ- mental issues accompanied by the intensive use of chemical inputs has led to increased concerns and the need for alternate forms of crop protection in the world (Adesina, 2013). The crude aqueous extracts evaluated in this study have been reported to contain insecticidal, termitici- dal, antifeedant, ovacidal and larvacidal properties (Ahmed, 1993; Shaaya et al., 1977; David, 1989; Jahan et al., 1991; Abayeh et al., 1999; Abbassi et al., 2003; Umsalama et al., 2006; Bakavathiappan et al., 2012; Katunku et al., 2014; Nagawa et al., 2015; Okoli et al., 2016). The result of the study showed that the crude plant extracts were able to reduce insect popu- lation, but not significantly, compared to the synthet- ic insecticide, but were able to show some suppress- ing effect on the rate of feeding of the insects as the severity of the leaves damaged by the insects was not enough to cause significant reduction in yield compared to results obtained from okra plants sprayed with chemical. The target insects are notorious for leaves defolia- tion owing to their biting and chewing mouthparts resulting in reduction of photosynthetic ability of the infested plants which invariably affect the plant growth and yield (Dent, 1999). The aqueous extracts were not effective at first two weeks of application. Synthetic insecticide recorded a higher efficacy com- pared to aqueous extract. This might be as a result of active ingredients of aqueous extracts being easily volatilized especially in the sun, thereby leading to their limited efficacy (Ware, 2000) and the delayed effect of aqueous extracts is reported to be one of t h e m a j o r p r o b l e m s o f b o t a n i c a l i n s e c t i c i d e s (Oparaeke, 2006; Isman, 2008). Since the beetles live and feed on the vegetative parts, any chemical that shows a remarkable efficacy against them must have contact toxicity, repellent or anti-feeding action. Several authors have reported that, the deleterious effects of crude plant extracts on insects are manifested in several ways, including toxicity (Hiremath et al., 1997) and feeding inhibition (Klepzig and Schlyter, 1999; Wheeler and Isman, 2001). Thus, reducing the level of beetle infestation and increasing okra pod carrying capacity; this con- firmed the earlier report of Thirumalai et al. (2003)+ = Present, - = absent. Table 7 - Phytochemical screening of crude aqueous extract of C. procera, C. schweinfurthii and B. coccineus Chemical constituents Calotrophus procera Canarium schweinfurthii Bryscocarpus coccineus Alkaloids - - + Terpenoids + - + Flavonoids + + + Anthraquinones - - + Tannins + + + Phlobatanins + - + Saponins + + + Cardiac glycosides + + + Steroids + + + Adv. Hort. Sci., 2018 32(1): 71-78 76 who observed the effective reduction of mite popula- tion with application of neem seed kernel extract. The reduction in Podagrica beetle population and increase in yield caused by the plant extracts treat- ment was comparable with those caused by synthetic insecticide. This supports the findings of Katunku et al. (2014) and those of Yusuf and Mohammed (2009) who reported that C. schweinfurthii and Monordica balsamina powder treatments were as effective as and comparable to permethrin and pirimiphos methyl in suppressing C. maculatus population and growth in cowpea storage. The high rate of Podagrica spp. population reduc- tion on exposure to the aqueous extracts treatments may be attributed to the chemical composition of the products. Plant extracts often consist of complex mixtures of bioactive constituents which may act as antifeedants, disturb insect growth, development and inhibit oviposition (Gerard and Ruf, 1991; Emimal Victoria, 2010). Thus, suggesting that most of the secondary metabolites such as terpenoids and alkaloids can be used as active insecticidal com- pounds that could be an effective alternative to syn- thetic insecticides for insect pest management. The toxicity of alkaloids was reported by Abbassi et al. (2003) and David (1989) reported that tannic acid acts as toxin and feeding deterrent to insects. Bernhoft (2010) reported that saponnins is found to affect the respiratory system of insects and causes emetic effect due to their detergent action. In the same vein, Philip et al. (2009) reported that plant products have repellent properties and toxic effect on the heart muscles in insects. Frazier (1986) report- ed that antifeedants can be found amongst all major c l a s s e s o f s e c o n d a r y m e t a b o l i t e s ( a l k a l o i d s , flavonoids, terpenoids and phenolics). Plant metabo- lites may produce toxic effects if ingested leading to rejection of the host plant (Russel and Lane, 1993). The utilization of C. schweinfurthii and B. coccineus aqueous extracts had positive toxicity impact in decreasing the rate of Podagrica spp. infestation and also increased the yield of okra plant thus could serve as alternative to synthetic insecticide to protect okra plant against Podagrica spp. infestation to maximize the yield and income of the resource poor farmers. 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