Microemulsion Formulations Of Rotenone And Their Effectiveness Against The Diamondback Moth (Lepidoptera: Yponomeutidae)

Oil-in-water (O/W) microemulsions were prepared by the titration method through phase diagram study. The mixture consisted of surfactant, oil (as carrier), and water. The surfactants were Agnique PG 8107-U, Agnique PG 9116, and Tween 20 while the oils were Agnique BL 7001, Agnique BL 7002, and xylene. The potential of plant-derived insecticide rotenone (Derris elliptica) microemulsion formulations and their effectiveness against crucifer insect pest namely diamondback moth, Plutella xylostella were investigated in laboratory. The objectives of this study were, therefore, to formulate rotenone as microemulsion formulations through phase diagram study, to characterize the formulations, and to determine their LC50 on diamondback moth by bioassay study.Twelve phase diagrams of ternary systems were constructed and isotropic region were established. The systems having wider isotropic region were selected and they were Agnique 8107-U/Agnique BL 7001/water, Agnique 9116/Agnique BL 7001/water, Tween 20/Agnique BL 7001/water, Agnique PG 8107-U/Agnique BL 7002/water, Tween 20/Agnique BL 7002/water and Tween 20/Edenor ME/water systems. From these phase diagrams, 13 microemulsion solutions were derived. These microemulsion solutions were further evaluated for miscibility, surface tension, and particle size analysis. The phase diagram systems containing Tween 20 as the surfactant showed the greater ability to produce a wider isotropic (microemulsion) region compared to others. The miscibility test showed all surfactants mixed readily with water. In interaction with the all oil phases, Tween 20 showed better miscibility compared with Agnique PG 8107-U and Agnique PG 9116 which produce double layers isotropic emulsion in absence of water. The width of isotropic/transparent region in phase diagrams constructed measured in decreasing order were; Tween 20/Agnique BL 7002/ water > Tween 20/Agnique BL 7001/water > Tween 20/Edenor ME/water > Agnique PG 9116/Agnique BL 7001/water > Agnique PG 8107-U/Agnique BL 7001/water > Agnique PG 8107-U/Agnique BL 7002/water > Tween 20/xylene/water > Agnique PG 9116/Agnique BL 7002/water > Agnique PG 9116/xylene/water > Agnique PG 8107-U/xylene/water > Agnique PG 8107-U/Edenor ME/water > Agnique PG 9116/Edenor ME/water.Three phase diagram systems representing the best microemulsifiable characterization properties and solubility with rotenone were Tween 20/Agnique BL 7001/water, Tween 20/Agnique BL 7002/water and Tween 20/Edenor ME/water systems. Six points in the isotropic regions of the selected phase diagrams were utilized to prepare the microemulsion and coded as M1 to M13. The microemulsions were then subjected to the determination of their surface tensions and particle sizes. The surface tension values of the selected microemulsions were low and their values in decreasing order were; M9 (27.3 mN/m) > M13 (26.9 mN/m) > M2 (26.8 mN/m) > M4 (26.4 mN/m) > M11 (22.8 mN/m) > M7 (22.7 mN/m). The particle size of the microemulsion in decreasing order were; M4 (207.57 nm) > M13 (83.31 nm) > M2 (68.7 nm) > M11 (49.03 nm) > M9 (35.86 nm) > M7 (20.63 nm). The selected microemusions were used to prepare the rotenone microemulsion formulations. The formulations were then evaluated for their toxicity in comparison with the standard commercial EC formulation (Saphyr®) against the early third instar larvae of the diamondback moth by leaf-dipped bioassay in the laboratory. The mortality of the larvae was recorded at 72 and 96 hours following treatment and data were subjected to the Probit analysis to establish the LC50 and LC95. Based on LC50 values, the toxicity of formulations for 72 hours after treatment in decreasing order were M11 (204.82 ppm) > M7 (139.71 ppm) > M13 (129.89 ppm) > M4 (122.8 ppm) > M2 (116.94 ppm) > M9 (96.09 ppm) > Saphyr® (96.05 ppm) while for 96 hours after treatment, the toxicity in decreasing order were M11 (166.63 ppm) > M7 (119.58 ppm) > M13 (105.82 ppm) > M2 (105.22 ppm) > M4 (97.67 ppm) > M9 (87.22 ppm) > Saphyr® (76.86 ppm). The toxicity study indicated that the rotenone microemulsion formulations especially M9 were comparable to commercial rotenone, Saphyr®

Identification of Cordyceps javanica and its effectiveness in Controlling Bagworm, Pteroma pendula JOANNIS (LEPIDOPTERA: PSYCHIDAE)

The application of biological control agents as one of the control methods to suppress the infestation of bagworm in Malaysia has developed steadily with the inundation release of formulated entomopathogenic microbes to the outbreak area. In this study, we isolated and identified the entomopathogenic fungi (EPF) from the dead larvae of the bagworm, Pteroma pendula. Mycoses dead bodies of P. pendula were collected from two locations in Kemayan, Pahang, Malaysia. Morphological characterization of EPF was carried out by observing the macroscopic and microscopic growth on Potato Dextrose Agar (PDA) plates using a compound microscope. It was observed that white colonies on PDA changed into purple or pink shades after sporulation. The colony is slow-growing with floccose mycelium, which produces conidiophores with three to four phialides. The conidia were cylindrical to fusiform, smoothwalled and formed in chains on mononematous conidiophores. All the isolates were observed to be similar to Cordyceps fumosorosea features. Molecular identification using universal primer (ITS4 and ITS5) has identified that the isolates were Cordyceps javanica and Parahevansia koratensis. Bioassays of identified isolates were carried out against the second instar larvae of Pteroma pendula showed that C. javanica isolates BSB01 achieved LT50 - 6.76 days and recorded the shortest lethal time compared to the other isolates

The insect pest management strategies and their influence on the emergence rate of elaeidobius kamerunicus faust (Coleoptera: Curculionidae) from the post-anthesising male inflorescence of oil palm, Elaeis guineensis

Elaeidobius kamerunicus is the main pollinating insect of oil palm, Elaeis guineensis in Malaysia. Elaiedobius kamerunicus feeds and breeds on the oil palms' male inflorescences. The weevil presence is vital for the successful pollination of oil palm, thus ensuring satisfactory fruit bunch production. MPOB recently reported that the declining quality of oil palm fruit bunch, mainly due to insufficient pollination, had affected the national average oil extraction rate. In part, this scenario was caused by the declining pollinator population. As such, the factors affecting the pollinators' population need to be investigated. One of the critical criteria in estimating the population of E. kamerunicus in the field is to measure the emergence rate of the new adult E. kamerunicus from the post-anthesis male inflorescence (PAMI). The study to investigate the rate of E. kamerunicus adult emergence and their sex ratio was conducted for four months at nine oil palm estates in Malaysia by using PAMI samples that were brought to the laboratory and observed for two weeks. The results have shown that the number of adult weevils that emerged from PAMI was about 36-47 individuals, and the female-to-male ratio for the emerged progenies was 2.33-4.46: 1. Indiscriminate application of broad-spectrum pyrethroid insecticide, cypermethrin has negatively influenced the weevil emergence rate in the field. Whereas, minimal impact on the emergence rate was observed in areas applied with biopesticide. This study showed that the application of cypermethrin could threaten the future population of the pollinating weevil in the field. As such, the excessive application of such insecticides in the field is discouraged and should be replaced by biopesticides to complement other Integrated Pest Management (IPM) strategies. In addition, further investigation is needed to understand how the gender ratio of the progeny could affect the future population of E. kamerunicus

Effects of neem oil, Azadirachta indica a. juss on growth and survival of bagworm, Metisa plana (lepidoptera: psychidae) larvae

Bagworm, Metisa plana Walker (Lepidoptera: Psychidae) is a major leaf-defoliating insect pest that has gained national attention due to the severe damage and loss to oil palm crops, notably in Peninsular Malaysia. The plant-derived insecticide neem, Azadirachta indica A. Juss provides a sustainable alternative as a biological control tool. This study was aimed to evaluate the growth and survival of M. plana after exposed to different concentrations of neem oil (75, 37.50, 18.75, 9.38, 4.69, and 2.35 mg/L) under laboratory conditions with distilled water used as control treatment. The bioassays of the neem extract were assessed using a leaf-dipping technique on fourth and fifth instar larvae stages of M. plana collected from Tapah, Perak, Malaysia. Observations were made during three exposure intervals: 1, 2, and 3 days after treatment (DAT). Higher concentrations of the neem oil had significantly increased the bagworm larval mortality at 3 DAT (ranging from 30% to 97.67%) and inhibited larvae growth which survived to adulthood. The highest % mortality was 96.67% and 83% for the fourth and fifth instar larvae after 3 DAT at a concentration of 75 mg/L, respectively. The lethal concentration, LC50 within 3 DAT indicated a value of 3.59 and 6.15 mg/L for the fourth and fifth instar larvae, respectively. The findings demonstrated that neem oil as an insect growth regulator exhibited inhibitory properties against the growth and survival of the bagworm larvae, resulting in a notable increase in mortality. Therefore, neem possesses the potential to be utilized as a substitute biopesticide for M. plana, which requires more field investigations

Effects of neem oil, Azadirachta indica A. juss on growth and survival of bagworm, Metisa plana (LEPIDOPTERA: PSYCHIDAE) LARVAE

Bagworm, Metisa plana Walker (Lepidoptera: Psychidae) is a major leaf-defoliating insect pest that has gained national attention due to the severe damage and loss to oil palm crops, notably in Peninsular Malaysia. The plant-derived insecticide neem, Azadirachta indica A. Juss provides a sustainable alternative as a biological control tool. This study was aimed to evaluate the growth and survival of M. plana after exposed to different concentrations of neem oil (75, 37.50, 18.75, 9.38, 4.69, and 2.35 mg/L) under laboratory conditions with distilled water used as control treatment. The bioassays of the neem extract were assessed using a leaf-dipping technique on fourth and fifth instar larvae stages of M. plana collected from Tapah, Perak, Malaysia. Observations were made during three exposure intervals: 1, 2, and 3 days after treatment (DAT). Higher concentrations of the neem oil had significantly increased the bagworm larval mortality at 3 DAT (ranging from 30% to 97.67%) and inhibited larvae growth which survived to adulthood. The highest % mortality was 96.67% and 83% for the fourth and fifth instar larvae after 3 DAT at a concentration of 75 mg/L, respectively. The lethal concentration, LC50 within 3 DAT indicated a value of 3.59 and 6.15 mg/L for the fourth and fifth instar larvae, respectively. The findings demonstrated that neem oil as an insect growth regulator exhibited inhibitory properties against the growth and survival of the bagworm larvae, resulting in a notable increase in mortality. Therefore, neem possesses the potential to be utilized as a substitute biopesticide for M. plana, which requires more field investigations

Quad trap: an alternative approach to increase trapping efficiency of the male bagworm, Metisa Plana Walker

Mass trapping plays an important role in insect pest management strategies by effectively monitoring and controlling the pest population. Various trap designs have been developed to optimise these traps' capture efficiency and reliability. This study compares two trap designs, the Mono trap and the Quad trap, for controlling the male of bagworm in oil palm plantations. The Mono trap is made from a one-unit white transparent plastic bag with two wooden poles, while the Quad trap is a four-unit white transparent plastic bag connected with raffia rope and tied between two oil palm trunks. There is a significant difference in the mean number of male moths captured between the two traps (P-value = 0.0028), where Quad trap captured more male moth (594.2) than Mono trap (68.4). The results show that the Quad trap is significantly more efficient in terms of male moth capture, increasing the number of male moths caught (m2) by 54% and reducing half installation time from 6 minutes to 3 minutes. The cost per unit trap is significantly cheaper at RM10.05 per set compared to the Mono trap (RM25.40). The Quad trap offers an alternative method of male moth control, making it easy to set up, affordable price, and requires no heavy lifting equipment. Thus, mass trapping of male moth bagworms using a Quad trap could complement other insect pest management components more effectively

Observation and trapping of insects visiting male and female inflorescences of oil palm

The African oil palm, Elaeis guineensis, relies heavily on entomophily. The absence of insect pollinators will cause inadequate fruit setting and in extreme situations, triggering bunch failure, especially in young palms. Fruit bunches of high quality are produced with adequate pollination, ensuring a high rate of oil extraction. The presence of the oil palm pollinating weevil, Elaeidobius kamerunicus in both sexes of the oil palm inflorescence is well-documented. However, reports on the presence of other insects, which may provide complementary pollination services, are still lacking. In addition, the presence of native oil palm pollinators in Sarawak was not recorded before the introduction of the weevil in the early 1980s. As such, this study investigates the presence of insect visitors and activity on sixteen male and female oil palm inflorescences at MPOB Sessang Research Station, Sarawak, Malaysia. The male inflorescences attracted more insect visitors than the female, as 87.6% of the insects were captured on the male inflorescences. From a total of 16 insect morphospecies identified, the two most abundant species caught were E. kamerunicus and Pyroderces sp. In addition, a host of other insect species were also observed, frequenting both sexes of the inflorescences. These insects may serve their respective ecological functions on oil palm inflorescences. Here, the presence of one of the native oil palm pollinators, Pyroderces sp. in Sarawak was confirmed, which has not been previously reported

Elements of eating morality according to Bediuzzaman Said Nursi’s views: a complementary to the basic concept of food in Islam

The issue of food wastage is considered as a problematic global issue stemmed from lack appreciation of food values gifted to mankind. Learning and taking lessons from historical events are crucial to establish a better future mainly to find solutions in solving arising contemporary issues. The view from Bediuzzaman Said Nursi who is one of the prominent Muslim thinkers (1877-1960), is chosen as a role model to understand the elements of eating morality. His work, Risale-I nur (Flashes of Collection) will be used as the main source of reference. Meanwhile, other Islamic sources derived from Quranic verses, academic journals, book, and reliable websites are used as supportive references. The result of the discussion signifies Bediuzzaman Said Nursi's view on the elements of eating morality are capable to complement the basic concept of food in Islam and it is still relevant to be adopted in facing rapid phases of urbanization process and modernization challenges which lead to morality declination among human beings

The insect pest management strategies and their influence on the emergence rate of Elaeidobius kamerunicus Faust (Coleoptera: Curculionidae) from the post-anthesising male inflorescence of oil palm, Elaeis guineensis

Elaeidobius kamerunicus is the main pollinating insect of oil palm, Elaeis guineensis in Malaysia. Elaiedobius kamerunicus feeds and breeds on the oil palms' male inflorescences. The weevil presence is vital for the successful pollination of oil palm, thus ensuring satisfactory fruit bunch production. MPOB recently reported that the declining quality of oil palm fruit bunch, mainly due to insufficient pollination, had affected the national average oil extraction rate. In part, this scenario was caused by the declining pollinator population. As such, the factors affecting the pollinators' population need to be investigated. One of the critical criteria in estimating the population of E. kamerunicus in the field is to measure the emergence rate of the new adult E. kamerunicus from the post-anthesis male inflorescence (PAMI). The study to investigate the rate of E. kamerunicus adult emergence and their sex ratio was conducted for four months at nine oil palm estates in Malaysia by using PAMI samples that were brought to the laboratory and observed for two weeks. The results have shown that the number of adult weevils that emerged from PAMI was about 36-47 individuals, and the female-to-male ratio for the emerged progenies was 2.33-4.46: 1. Indiscriminate application of broad-spectrum pyrethroid insecticide, cypermethrin has negatively influenced the weevil emergence rate in the field. Whereas, minimal impact on the emergence rate was observed in areas applied with biopesticide. This study showed that the application of cypermethrin could threaten the future population of the pollinating weevil in the field. As such, the excessive application of such insecticides in the field is discouraged and should be replaced by biopesticides to complement other Integrated Pest Management (IPM) strategies. In addition, further investigation is needed to understand how the gender ratio of the progeny could affect the future population of E. kamerunicus

Identification of Cordyceps javanica and its effectiveness in controlling bagworm, Pteroma pendula Joannis (Lepidoptera: Psychidae)

The application of biological control agents as one of the control methods to suppress the infestation of bagworm in Malaysia has developed steadily with the inundation release of formulated entomopathogenic microbes to the outbreak area. In this study, we isolated and identified the entomopathogenic fungi (EPF) from the dead larvae of the bagworm, Pteroma pendula. Mycoses dead bodies of P. pendula were collected from two locations in Kemayan, Pahang, Malaysia. Morphological characterization of EPF was carried out by observing the macroscopic and microscopic growth on Potato Dextrose Agar (PDA) plates using a compound microscope. It was observed that white colonies on PDA changed into purple or pink shades after sporulation. The colony is slow-growing with floccose mycelium, which produces conidiophores with three to four phialides. The conidia were cylindrical to fusiform, smoothwalled and formed in chains on mononematous conidiophores. All the isolates were observed to be similar to Cordyceps fumosorosea features. Molecular identification using universal primer (ITS4 and ITS5) has identified that the isolates were Cordyceps javanica and Parahevansia koratensis. Bioassays of identified isolates were carried out against the second instar larvae of Pteroma pendula showed that C. javanica isolates BSB01 achieved LT50 - 6.76 days and recorded the shortest lethal time compared to the other isolates