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

Toxicity Azadirachta indica and Piper Sarmentosum extract mixture formulations against Nilaparvata lugens (Hemiptera: Delphacidae) in paddy field

Infestation of Nilaparvata lugens on rice in Malaysia is not as heavy compared to other Asian countries, but still lower the rice yield production. Nilaparvata lugens is developing resistance against chemical pesticide, therefore an alternative approach such as the application of botanical pesticide is potential to control the N. lugens. The aims of this research were to determine the synergistic activity in combination of Azadirachta indica and Piper sarmentosum emulsion formulations extract against Nilaparvata lugens. Three formulations were developed were coded as F1, F2, and F3. The F1 was selected as the best formulation because it in range of good zeta potential value (-48.3 mV) and viscosity value (100.1 mPa/s), the lowest particle size (202.5 nm), remained homogenous for centrifugation and stability test, polydispersity index (PDI) value indicated it is in ideal monodisperse phase (0.359), low surface tension (31.3 mN/m) and low pH (3.65). The lethal concentration, LC50 and sub lethal, LC10 and LC25 were determined from nymph mortality bioassay test on third instar N. lugens nymphs. Mortality rate of F1 and F2 were 0.011 mg/l and F3 was 0.031 mg/l. The value of lethal and sublethal concentration were used in a test against female N. lugens to determine the effect of formulations on fecundity of N. lugens. There were significant differences between formulations on the number of eggs produced after treatments. The lowest egg produced from F1 with 128.11 number of eggs. It can be concluded that all formulations showed promising result in controlling N. lugens

First report of leaf blight on Parthenium hysterophorus caused by Nigrospora sphaerica in Malaysia

Weeds may act as inoculum reservoirs for fungal pathogens that could affect other economically important crops (Karimi et al. 2019). In February 2019, leaves of the ubiquitous invasive weed, Parthenium hysterophorus L. (parthenium weed) exhibiting symptom of blight were observed at Ladang Infoternak Sg. Siput (U), a state-owned livestock center in Perak, Malaysia. Symptoms appeared as irregularly shaped, brown-to-black necrotic lesions across the entire leaf visible from both surfaces, and frequently on the older leaves. The disease incidence was approximately 30% of 1,000 plants. Twenty symptomatic parthenium weed leaves were collected from several infested livestock feeding plots for pathogen isolation. The infected tissues were sectioned and surface-sterilized with 70% ethyl alcohol for 1 min, rinsed three times with sterile distilled water, transferred onto potato dextrose agar, and incubated at 25°C under continuous dark for 7 days. Microscopic observation revealed fungal colonies with similar characteristics. Mycelium was initially white and gradually changed to pale orange on the back of the plate but later turned black as sporulation began. Conidia were spherical or sub-spherical, single-celled, smooth-walled, 12 to 21 μm diameter (mean = 15.56 ± 0.42 μm, n= 30) and were borne on a hyaline vesicle. Based on morphological features, the fungus was preliminarily identified as Nigrospora sphaerica (Sacc) E. W. Mason (Wang et al. 2017). To confirm identity, molecular identification was conducted using isolate 1SS which was selected as a representative isolate from the 20 isolates obtained. Genomic DNA was extracted from mycelia using a SDS-based extraction method (Xia et al. 2019). Amplification of the rDNA internal transcribed spacer (ITS) region was conducted with universal primer ITS1/ITS4 (White et al. 1990; Úrbez-Torres et al. 2008). The amplicon served as a template for Sanger sequencing conducted at a commercial service provider (Apical Scientific, Malaysia). The generated sequence trace data was analyzed with BioEdit v7.2. From BLASTn analysis, the ITS sequence (GenBank accession number. MN339998) had at least 99% nucleotide identity to that of N. sphaerica (GenBank accession number. MK108917). Pathogenicity was confirmed by spraying the leaf surfaces of 12 healthy parthenium weed plants (2-months-old) with a conidial suspension (106 conidia per ml) collected from a 7 day-old culture. Another 12 plants served as a control treatment and received only sterile distilled water. Inoculation was done 2 h before sunset and the inoculated plants were covered with plastic bags for 24 h to promote conidial germination. All plants were maintained in a glasshouse (24 to 35°C) for the development of the disease. After 7 days, typical leaf blight symptoms developed on the inoculated plants consistent with the symptoms observed in the field. The pathogen was re-isolated from the diseased leaves and morphological identification revealed the same characteristics as the original isolate with 100% re-isolation frequency, thus, fulfilling Koch's postulates. All leaves of the control plants remained symptomless and the experiment was repeated twice. In Malaysia, the incidence of N. sphaerica as a plant pathogen has been recorded on several important crops such as watermelon and dragon fruit (Kee et al. 2019; Ismail and Abd Razak 2021). To our knowledge, this is the first report of leaf blight on P. hysterophorus caused by N. sphaerica from this country. This report justifies the significant potential of P. hysterophorus as an alternative weed host for the distribution of N. sphaerica

The fall armyworm (Faw) spodoptera frugiperda: a review on biology, life history, invasion, dispersion and control

The fall armyworm (FAW) is a most devastating pest that has great threats to the food security of the world. There are various reasons that make this pest one of the world’s most invasive species including; they are polyphagous, have a high reproduc-tive rate and they can migrate long distance. We review FAW global life history, invasions and their management

In-vitro culture and developmental changes of yellow stem borer Scirpophaga incertulas Under Different microclimate conditions on the MR297 rice variety

Scirpophaga incertulas (Walker) (Lepidoptera: Crambidae), also called the Yellow Stem Borer, is a major prominent insect pest in rice production that results in substantial crop losses. Due to climate change, the infestation of S. incertulas has become more serious. This study was carried out between March and April 2022 to investigate the in-vitro culture and developmental changes of S. incertulas under different microclimates on the MR297 rice variety. The experiment was set up in a completely randomized design, and the data on the mean developmental stages of the lengths and widths were measured. A student's t-Test was used to compare the mean differences in lengths and widths of the developmental changes in instar larvae and pupae of S. incertulas in the two microclimate conditions. Multi-linear regression analysis was used to correlate the relationship between the microclimate factors and the developmental changes in S. incertulas on the MR297 rice variety. Data were analyzed using SPSS (version 20) and R studio (version 4.2.1) software. The correlation analysis of the data showed a positive relationship between the developmental changes in lengths and widths of S. incertulas for the laboratory and field microclimatic conditions using the MR297 rice variety. This study successfully examined the in-vitro culture and developmental changes of S. incertulas under different microclimates, from egg hatching to the adult's emergenc

In-vitro culture and developmental changes of yellow stem borer Scirpophaga incertulas Under Different microclimate conditions on the MR297 rice variety

Scirpophaga incertulas (Walker) (Lepidoptera: Crambidae), also called the Yellow Stem Borer, is a major prominent insect pest in rice production that results in substantial crop losses. Due to climate change, the infestation of S. incertulas has become more serious. This study was carried out between March and April 2022 to investigate the in-vitro culture and developmental changes of S. incertulas under different microclimates on the MR297 rice variety. The experiment was set up in a completely randomized design, and the data on the mean developmental stages of the lengths and widths were measured. A student's t-Test was used to compare the mean differences in lengths and widths of the developmental changes in instar larvae and pupae of S. incertulas in the two microclimate conditions. Multi-linear regression analysis was used to correlate the relationship between the microclimate factors and the developmental changes in S. incertulas on the MR297 rice variety. Data were analyzed using SPSS (version 20) and R studio (version 4.2.1) software. The correlation analysis of the data showed a positive relationship between the developmental changes in lengths and widths of S. incertulas for the laboratory and field microclimatic conditions using the MR297 rice variety. This study successfully examined the in-vitro culture and developmental changes of S. incertulas under different microclimates, from egg hatching to the adult's emergency

Efficacy of Phaleria macrocarpa crude extract to control black apple snail Pomacea maculata Perry

The highest saponin contents 82.3% to 82.4% were detected in fruits extract of Phaleria macrocarpa followed by 75.2% to 75.7%. in leaves extract. In terms of mortality, 100 % mortality was observed at 1000 and 750 ppm concentration of fruits and leaves extract after exposure of 48 hours. Similarly, in terms of leaves area and weight consumption, 1000, 750 and 500 ppm concentrations of both crude extracts were also not significantly different from positive control niclosamide

Weed Control Efficacy and Crop-Weed Selectivity of a New Bioherbicide WeedLock

Plant-based bioherbicides could be an effective alternative to current chemical herbicides for sustainable agriculture. Therefore, this research evaluated the weed control efficacy and crop-weed selectivity of the new plant-derived bioherbicide WeedLock compared to commercial herbicides in glasshouse and field conditions. In the glasshouse, the herbicides applied were WeedLock (672.75, 1345.50, 2691.00 L ha−1), glyphosate isopropyl-amine, and glufosinate-ammonium (1, 2, 4 L ha−1), over the untreated (control) on six weeds and four crops. In the field trial, typical weeds were allowed to grow at a uniform density across plots (2.5 × 2.5 m), and WeedLock (1345.50, 2691.00 L ha−1), glyphosate isopropyl-amine, and glufosinate-ammonium (2, 4 L ha−1) were applied along with untreated plot (control). A randomized complete block design was set with four replications for glasshouse and field experiments. WeedLock at 1345.50 L ha−1 showed efficacy similar to glyphosate isopropyl-amine and glufosinate-ammonium at 2 L ha−1 for Ageratum conyzoides L. in the glasshouse. Applied herbicides killed all tested crops except Zea mays L. at 1345.50 L ha−1 (WeedLock). WeedLock showed more than 50% efficacy at 35 days after spray, while 65% was produced by glyphosate isopropyl-amine and glufosinate-ammonium compared to the untreated plot (control). WeedLock has excellent potential to control weeds in both glasshouse and field conditions and showed a non-selective character