6 research outputs found
Molluscicidal and feeding deterrent activity of crude plant extracts on Pomacea maculate Perry
This study was focused on molluscicidal effect and feeding deterrent activity of saponin from five different plant materials; Andrographis paniculata, Entada spiralis, Ficus deltoidea, Furcraea selloa and Ipomoea batatas. Crude plant extracts were prepared from plant powders using methanol. The crude extracts were then tested on Pomacea maculata using five different concentrations (5, 10, 15, 20 and 25 ppm, respectively) against niclosamide (control). After 72 h of exposure, the highest percentage of mortality of 80% was achieved from 15 ppm of F. selloa. Two analyses were conducted to observe the feeding deterrent activity and after 24 h, both analyses demonstrated the feeding deterrent activity in both crude extracts (F. selloa and E. spiralis) similar in niclosamide
Preparation and characterization of neem oil nanoemulsion formulations against Sitophilus oryzae and Tribolium castaneum adults
This study aimed to improve the efficacy of azadirachtin (Azadirachta indica. A. Juss) against two serious pest species of stored products, Sitophilus oryzae (L.) and Tribolium castaneum (Herbst), through nano-emulsion formulations. Pseudoternary phase diagrams were constructed consisting of an emulsion system of an active ingredient (neem oil), surfactant (polysorbate or alkylpolyglucoside), and water. Isotropic regions were formed in the pseudoternary phase diagrams, and four formulations were selected from the isotropic regions and characterized according to particle size, particle aging, zeta potential, stability and thermostability, surface tension, viscosity, and pH. The selected formulations showed particle sizes of 208–507 nm in diameter. The result of contact toxicity demonstrated excellent mortality of S. oryzae and T. castaneum adults, with a mortality range of 85–100% and 74–100%, respectively, at a 1% azadirachtin concentration after only 2 days of exposure. Compared to non-formulated neem oil, the nano-emulsion formulations significantly increased the mortality of the tested species
Secondary poisoning in captive barn owls Tyto alba javanica from feeding with rats poisoned with chlorophacinone and bromadiolone
The potential secondary hazards of two anti-coagulant rodenticides commonly used in Malaysian oil palm plantations were evaluated through feeding trials with captive barn owls. A total of 12 adult barn owls (six pairs) were assigned to two rodenticide treatments and a control. The two treatments were rats fed with bromadiolone (0.005% a.i) and chlorophacinone (0.005% a.i) respectively. All rodenticide treated owls received four poisoned rats at Day 1, 3, 5 and 7 and a non-poisoned rat on each intervening day for 30 days. Each barn owl of the control group received a non-poisoned rat throughout the study. The reliability of a non-invasive technique such as an estimation of anti-coagulant rodenticide residue in regurgitated pellets and blood samples, were also evaluated. Barn owls showed behavioural aberrations such as coarse breathing, frequent closing of the eyes and reduced flying activity as early as Day 5 after consuming three poisoned rats. The weight recorded at Day 7 after treatment showed that all treated owls registered a reduction in weight. The owls in the control group on the contrary gained weight. Bromadiolone and chlorophacinone were found to have high degree of toxicity on captive barn owls. After feeding the birds with as few as four poisoned rats in a week the signs of toxicity in birds such as haemorrhages (beak) and haematoma (wing) were found. This finding is very crucial since barn owls have been reported to consume up to three rats per night and this would certainly increase their potential exposure to lethal secondary poisoning. The detection of residue in the pellets regurgitated by barn owls can be used to indicate exposure of the latter to both compounds. However, as the blood residue method is limited to the exposure duration of the compounds, this technique can only detect recent exposure to bromadiolone and chlorophacinone. The amount of residue detected in the pellet samples for chlorophacinone was 69.9 to 81.6 μg per day or equivalent to 17.2% to 27.4% of the compound consumed and corresponding value for bromadiolone was 27.2% to 34.5% (72.24 – 85.77 μg per day). This suggests that the amount of bromadiolone retained in the tissue of the rats was higher than that of chlorophacinone. Thus, barn owls face a greater potential for secondary poisoning from bromadiolone rather than chlorophacinone as can be deduced from this study
Solar heater system to disinfect seeds
A solar heater box for treatment of seeds which comprise of a layered reflective surface having a square-based pyramid frustum shape, wherein the inner layer and of the surface reflects and focuses radiant energy into a receiving platform, providing substantially uniform heating along the receiving platform, wherein the outer layer and of the solar heater is adapted to provide thermal insulation to the solar heater box
Relationship between Metisa plana and its parasitoids (braconidae and ichneumonidae) at different time-lags in oil palm plantation
Bagworm or Metisa plana, is the most important defoliator insect in the oil palm cultivation,
while parasitoids such as Braconidae and Ichneumonidae are the common main natural
enemies for bagworm. Although the relationship between natural enemies with its insect pest
has been broadly investigated, little is dedicated for assessing the delayed effects of the
bagworm population on parasitoids. In this study, the abundance relationship between
bagworm and its common parasitoids (Braconidae and Ichneumonidae) was assessed at
different time-lags under field condition. Bagworm censuses for instar stages first (L1) to seven
(L7) were conducted biweekly in an oil palm plantation belongs to TH Plantation Berhad in
Muadzam Shah, Pahang from July 2016 to July 2017, along with bagworm’s parasitoid from
Braconidae and Ichneumonidae family. The results revealed that Braconidae presence was
associated positively with bagworm at week 6 to 12, whereby the associations were stronger
for late instar stages. On the other hand, Ichneumonidae presence was positively related to
middle instar stages at early time-lag i.e. week 2 to 6. In other words, Ichneumonidae
population is expected to increase after 2 to 6 weeks given increasing population of bagworm,
while Braconidae population is likely to rise after 6 to 12 weeks of the increasing population
of bagworm