Moderate Infestation Research Articles

Distribution and Impact of Parthenium (Parthenium hysterophorus L.) on Weed Species Diversity in Maize Fields in Western Gojjam Zone, Amhara National Regional State, Ethiopia

An investigative weed flora survey was conducted in parthenium-infested maize fields in West Gojjam Zone in 2019/2020. The objective was to investigate the distribution and impact of parthenium on species diversity. A survey was conducted on 90 fields using 2 m × 2 m (4 m2) quadrats (totally 270). A total of 110 weed species belonging to 27 families were identified out of these families. Asteraceae with 26 species (23.36%) and Poaceae with 18 species (16.36%) were abundant. The highest importance value (IV) was recorded by Ageratum conyzoides, Amaranthus hybridus, and Bidens pilosa, with 28.05, 19.18, and 13.16%, respectively, in no parthenium infestation level. The highest IV of 27.08, 17.71, and 16.44%, respectively, was shown by Ageratum conyzoides, Bidens pilosa, and Galinsoga parviflora with 27.08, 17.71, and 16.44%, respectively, in very low parthenium infestation level. Ageratum conyzoides (29.38%), Bidens pilosa (24.10%), and Parthenium hysterophorus (22.68%) had the highest IV in low parthenium infestation level. Parthenium hysterophorus (91.32%), Ageratum conyzoides (17.19%), and Echinochloa colona (16.34%) had high IV in moderate parthenium infestation level. It is concluded that Ageratum conyzoides, Bidens pilosa, Echinochloa colona, and Galinsoga parviflora were competitive over parthenium based on importance value, and this indicates to suggest parthenium as a biological management option.

Estimation of liana infestation above canopy in Bukit Bakar recreational park, Kelantan using an unmanned aerial vehicle

A study on lianas estimation has been conducted in 1 ha plot at Bukit Bakar Recreational Park, Machang, Kelantan. Liana infestation on tree crowns was assessed from above by using an unmanned aerial vehicle (UAV), DJI Phantom-4 Pro which was manually piloted. Liana load carried by trees were determined by calculating the percentage liana cover (%LC) and measuring crown occupancy index (COI). Collection of image data by UAV had been captured and geo-tagged with GPS location. The value of crown occupancy index (COI) depends on the accuracy of the percentage liana cover (%LC). Fourteen host trees infested by lianas were identified. The value COI of 14 lianas-infested trees were in the range between 0 – 2, indicating low and moderate infestation. One point was recorded with very low liana load, nine points with moderate liana and four points with low liana load on tree crowns with 0.76% to 29.9% of liana cover respectively. The moderate and lower values obtained was probably due to the lesser of anthropogenic disturbance and natural disturbance that occurred after 40 years of selective management system logging. The liana infestation was distributed homogeneously. The lower liana COI obtained, indicates the ongoing progress of forest succession in Bukit Bakar that gradually hindered liana proliferation within the proximity. This method could promote the local authority in forestry management particularly in managing the tree crown occupancy of liana in the logged-over forest.

Lithium chloride outperformed oxalic acid sublimation in a preliminary experiment for Varroa mite control in pre-wintering honey bee colonies.

Since lithium salts were demonstrated to be very effective for the potential control of Varroa destructor, a highly detrimental parasite of honey bee (Apis mellifera), no studies have been reported on their comparison with any commonly used varroicides in commercial bee colonies. In this study we compared the effectiveness of lithium chloride to that of oxalic acid, a widely used miticide. The results of the present study confirm that lithium has superior efficacy to oxalic acid sublimation both as a main or a supplementary pre-wintering treatment at moderate infestation levels, restricted to certain pre-wintering conditions. Considering its easy implementation in apicultural practice and its twofold mode of action, trickling would be the preferred way of administration after the use of lithium salts as varroicides is authorised.

Identification of Cotton Root Rot by Multifeature Selection from Sentinel-2 Images Using Random Forest

Cotton root rot is a destructive cotton disease and significantly affects cotton quality and yield, and accurate identification of its distribution within fields is critical for cotton growers to control the disease effectively. In this study, Sentinel-2 images were used to explore the feasibility of creating classification maps and prescription maps for site-specific fungicide application. Eight cotton fields with different levels of root rot were selected and random forest (RF) was used to identify the optimal spectral indices and texture features of the Sentinel-2 images. Five optimal spectral indices (plant senescence reflectance index (PSRI), normalized difference vegetation index (NDVI), normalized difference water index (NDWI1), moisture stressed index (MSI), and renormalized difference vegetation index (RDVI)) and seven optimal texture features (Contrast 1, Dissimilarity 1, Entory 2, Mean 1, Variance 1, Homogeneity 1, and Second moment 2) were identified. Three binary logistic regression (BLR) models, including a spectral model, a texture model, and a spectral-texture model, were constructed for cotton root rot classification and prescription map creation. The results were compared with classification maps and prescription maps based on airborne imagery. Accuracy assessment showed that the accuracies of the classification maps for the spectral, texture, and spectral-texture models were 92.95%, 84.81%, and 91.87%, respectively, and the accuracies of the prescription maps for the three respective models were 90.83%, 87.14%, and 91.40%. These results confirmed that it was feasible to identify cotton root rot and create prescription maps using different features of Sentinel-2 imagery. The addition of texture features had little effect on the overall accuracy, but it could improve the ability to identify root rot areas. The producer’s accuracy (PA) for infested cotton in the classification maps for the texture model and the spectral-texture model was 2.82% and 1.07% higher, respectively, than that of the spectral model, and the PA for treatment zones in the prescription maps for the two respective models was 8.6% and 8.22% higher than that of the spectral model. Results based on the eight cotton fields showed that the spectral model was appropriate for the cotton fields with relatively severe infestation and the spectral-texture model was more appropriate for the cotton fields with low or moderate infestation.

Seasonal and spatial patterns of mudblister worm Polydora websteri infestation of farmed oysters in the northern Gulf of Mexico

Mudblister worms Polydora websteri bore holes into oyster shells, and oysters respond by secreting extra layers of shell, creating a mudblister. When shucked, mudblisters can burst and release anoxic mud. Thus, infestation devalues oysters, particularly on the half-shell market. This study quantified oyster condition index and worm abundances over 2 full growing seasons at commercial oyster farms on the US Gulf of Mexico coast, and our results indicate that oyster growth rate, manipulated through ploidy and stocking densities, had little effect on worm infestation. Larval spionid worms were found year-round. Larval abundances were slightly higher within than away from farms, and larval size distributions were skewed toward smaller larvae within the farms, suggesting that farms may be a source of larvae. Triploid oysters had higher or comparable condition index values to diploids, but during summer months, when worm infestation was high, worm infestation was not correlated with condition index. Previously infested shells deployed at farms became more infested than uninfested shells at moderate infestation levels, but re-infestation was influenced more by farm location than by previous infestation condition. Higher infestation at a farm with more variable salinity as well as higher infestation in 2017 when salinity was lower suggest that salinity may be a potential driver of mudblister worm infestation. Results indicate that oyster farmers on this coast should use desiccation to treat oysters for mudblister worms frequently during the summer, but that manipulating stocking density or ploidy is unlikely to be effective in preventing mudblister worm infestation.

Effects of Resident Education and Self-Implementation of Integrated Pest Management Strategy for Eliminating Bed Bug Infestation in Ahvaz City, Southwestern Iran.

Background:Bed bugs as blood-sucking insects have become a public health problem in urban communities throughout the world. The objective of this study was to determine the effects of resident education and self-implementation of Integrated Pest Management (IPM) strategy for eliminating bed bug infestation in infected apartments in Ahvaz City, Iran.Methods:This interventional study was conducted in seventy apartments infested with bed bug (Cimex lectularius) in Ahvaz City, southwest Iran, during a 6-month period. The bed bug infestations reported to Health centers were inspected visually and confirmed by medical entomology experts. Then, the heads of the households were received techniques/tools of the IPM program and trained by medical entomology experts before self-implementation of control methods. Finally, the infected apartments were inspected by the experts at 1, 3, and 6 months after intervention and data were recorded in a checklist.Results:From the seventy infected apartments, 57%, 28% and 15% were considered as low, moderate, and high level infestation respectively. The bed bug infestation was eliminated from 53 apartments (76%) after one month and it reached to 62 apartments (88%) by the end of third month. Finally, after six months of applying IPM program, bed bugs infestation was eliminated from all infected apartments (100%). Residents expressed their 100% satisfaction with applying the bed bug IPM strategy.Conclusion:Training residents to implement the IPM program can reduce pest control costs, the volume of pesticides consumed, and human exposure to chemical pesticides, resulting in increased human and environmental health and safety.

Evaluation of a plant-based food supplement to control flea populations in dogs: A prospective double-blind randomized study

A prospective double-blind randomized placebo-controlled study evaluated the tolerance and efficacy of the biological plant-based food supplement Bioticks® (extracts of thyme, rosemary, melissa, fenugreek, absinthe and lemongrass) as a flea-control product. Twelve dogs were used as placebo controls (group A). Ten dogs under similar housing conditions received the same food daily but supplemented with Bioticks® (group B). Flea counts were performed on D0 and 14, then 1, 2, 3, 4 and 5 months after the beginning of the study. No flea treatment was given or environmental modifications made during the 6 months prior to beginning and throughout the duration of the study. Efficacy was calculated according to Abbott's formula. No adverse event was recorded. At inclusion, dogs in groups A and B hosted a mean ± standard deviation of 7.9 ± 3.3 and 9.5 ± 3.6 fleas, respectively. The mean flea population in group A steadily increased until 4 months after D0 (21.5 ± 4.9 fleas/dog). Meanwhile, the mean flea population in group B dogs remained stable for the first month but then steadily decreased to reach an average of 3.1 ± 1.7 fleas/dog at D0+5 months. The percentage efficacy in the treated group as compared to the non-treated group was 33%, 51%, 71%, 80% and 82% at 1, 2, 3, 4 and 5 months, respectively.Bioticks® was shown to be safe and effectively limited the flea population in dogs with a moderate flea infestation in conditions that were highly favourable to flea development. This is the first study to evaluate a plant-based product as an oral supplement for flea control.

Histopathology of the gill of Vaname Shrimp (Litopenaeus vannamei) infested by protozoan ectoparasite

The aim of this study were to determine the changes of vaname gill which infested by ectoparasites and the correlation between the degree of ectoparasite infestation. The results showed that ectoparasites were found in the gill of vaname shrimp were Zoothamnium sp. and Epistylis sp… The degree infestation of the infested gills showed moderate infestations for Zoothamnium sp.; moderate and mild infestations for Epistylis sp. Histopathology analysis found haemorrhagi and hyperplasia. The correlation between the degree of ectoparasite infestation and the changes of vaname gill histopathology infested by ectoparasite showed a positive correlation (r = 0.926), which means that the high degree of the infestation, the higher histopathological changes.

Encephalic Babesiosis in Dogs: Clinical, Epidemiological and Pathological Aspects

Background: Babesiosis is a hemolytic disease caused by protozoa of the genus Babesia spp. responsible for causing anemia, fever and splenomegaly in several animal species. The Cerebral involvement of Babesiosis in dogs manifests itself in a hyperacute manner with neurological disorders such as motor incoordination, nystagmus, anisocoria and convulsions. In Brazil there still are no studies which describe the pathological aspects of cerebral Babesiosis in dogs together with information relating to its clinical aspects and epidemiology. Therefore, this work had as an objective to describe seven cases of canine Cerebral Babesiosis, emphasizing its epidemiological, clinical and pathological aspects.Materials, Methods & Results: Were identified all the records of the necropsies performed in dogs at Animal Pathology Laboratory of the Federal University of Campina Grande (LPA/HV/UFCG), Patos Campus, Paraíba, Northeast of Brazil. In The period from January 2003 to December 2017. Later, were sellected all the cases of cerebral Babesiosis. Were included in the study the cases in which was possible to detect structures that were morphologically compatible with Babesia spp. trophozoites, intra-erythrocyte in vessels, associated to the presence of lesions in the CNS. For the microscopical description all the histological slides of the cases were revised, in addition to new slides were made with the fragments stored in parafin blocks or with the material fixed in a 10% formalin solution. The clinical course of the animals studied was hyperacute. In 4 cases, there was sudden death within 24 hours, from the appearance of the first symptoms and case 7 presented an evolution of approximately 12 hours. The main clinical symptoms described were vocalization, anorexia/hyporexia, jaundice and decubitus. Additionally, the most consistente macroscopical findings observed during the necropsy were a diffuse orange-coloured liver and splenomegaly. The most consistent alterations in the canine cerebral Babesiosis were hypertrophy of the endothelial cells, monocytic leukostasis, non-supurative meningitis, in addition to congestion, thrombosis, hemorrhage, vasculitis and perivascular cuffs.Discussion: In all the dogs of the present study, it was possible the detection of structures morphologically compatible with Babesia spp. trophozoites, as well as structural alterations and layout of the parasited erythrocytes, and the reduction of the eosinophilia, sweeling and formation of clusters in contact with the endothelium. The high parasite load in the sections of the brain was not a very precise criterium to explain the death of the animals, since only 1 case presented high concentrations of parasited erythrocytes. The other cases with discreet and moderate parasitic infestation were fatal probably due to the antigens liberated by the agent which culminate in systemic responses, suggesting a high pathogenicity of the hemoparasite. It’s necessary to include hyperacute diseases in the differential diagnosis, mainly in puppies, as infectious canine hepatitis, however jaundice in these cases is rarely observed, additionally, at necropsy, there is a predominance of petechiae and ecchymosis in the mucous membranes of the intestine and stomach. More extensive hemorrhage is observed in the subcutaneous tissue, kidneys, lungs, heart, and histopathological visualization of liver necrosis with intranuclear basophilic or amphophilic body inclusions in hepatocytes, Kupffer cells or endothelial cells.

Shola tree regeneration is lower under Lantana camara L. thickets in the upper Nilgiris plateau, India

Lantana camara is a dominant invasive shrub in many protected areas of India including the Nilgiri Biosphere Reserve (NBR). We conducted a study to assess the regeneration potential of endemic native (shola) trees under different levels of Lantana infestation in the upper plateau of NBR. A total of 61 plots in a total area of 0.73ha were sampled, out of which 0.57ha was in Lantana dominated sites and 0.16ha in undisturbed shola forests. The plots were classified as per the level of Lantana infestation (intensive, moderate, and low infestation). We found that regeneration of shola trees, including endemics decreased with increasing intensity of Lantana invasion. No regeneration occurred in the intensively infested plots whereas regeneration was high in undisturbed shola forests.

34. Anatomical Pathology And Histopathological Changes Of Ascaridia Galli In Layer Chicken

This study aimed to determine the anatomical pathology and histopathological, and their relationship of the ascaridiosis caused by Ascaridia galli worms infection that have been found in layer chickens after necropsy, thus facilitating the diagnosis, treatment, and prevention of ascaridiosis. This study used 1 dead chicken from the Lambaro traditional market, Ingin Jaya District, Aceh Besar Regency. The sample was taken to the Pathology Laboratory, Faculty of Veterinary Medicine, Syiah Kuala University for dissected and observed in anatomical pathology changes, then histopathological preparations were made to observe histopathological changes. Data were obtained then analyzed descriptively and presented in the form of images. The results of anatomical pathology examination in chickens infected with ascaridiosis were found the Ascaridia galli worms infestation in the intestinal lumen with moderate infestation rates and focal area of hemorrhage in the intestinal mucosa. Then, histopathological examination were found desquamation of villous epithelium, hemorrhage in the intestinal mucosa, inflammatory cell infiltration, and proliferation of cryptic cells caused by A. galli worms infection. Based on the results of the examination concluded that there is an association between anatomical and histopathological pathology findings, namely hemorrhage in the intestine.

Economic Benefits of Controlling Red Rice: A Case Study of the United States

Red rice (O. sativa) is one the most prevalent and damaging weed problems in direct seeding rice systems worldwide and can cause significant losses in rice productivity and quality. Red rice has been a problem in the United States for decades, and it is a growing problem in Asia, where 90 percent of the global rice production occurs. Unlike for other crops, where genetically engineered (GE) herbicide tolerant varieties are available, to date, Clearfield (CL) and Provisia rice are the only technologies available to selectively control red rice using chemical herbicides in commercial rice fields. We develop a counterfactual scenario without CL rice and ascertain the yield and quality losses due to red rice infestation in the Mid-South of the United States. Our findings suggest that even with the higher costs of CL rice, relative to non-CL rice, that the returns are $0.15, $0.36, and $0.54 more for every dollar invested than non-CL rice with a light, moderate, and heavy initial red rice infestation rate, respectively. These results imply that the higher upfront costs for CL rice are offset by more than proportional higher profits relative to their non-CL rice counterparts.

The potential of dual-wavelength terrestrial lidar in early detection of Ips typographus (L.) infestation – Leaf water content as a proxy

Climate change is causing novel forest stress around the world due to changes in environmental conditions. Forest pest insects, such as Ips typographus (L.), are spreading toward the northern latitudes and are now able to produce more generations in their current range; this has increased forest disturbances. Timely information on tree decline is critical in allowing forest managers to plan effective countermeasures and to forecast potential infestation areas. Field-based infestation surveys of bark beetles have traditionally involved visual estimates of entrance holes, resin flow, and maternal-gallery densities; such estimates are prone to error and bias. Thus, objective and automated methods for estimating tree infestation status are required.In this study, we investigated the feasibility of dual-wavelength terrestrial lidar in the estimation and detection of I. typographus infestation symptoms. In addition, we examined the relationship between leaf water content (measured as gravimetric water content and equivalent water thickness) and infestation severity. Using two terrestrial lidar systems (operating at 905 nm and 1550 nm), we measured 29 mature Norway spruce (Picea abies [L.] Karst.) trees that exhibited low or moderate infestation symptoms. We calculated single and dual-wavelength lidar intensity metrics from stem and crown points to test these metrics' ability to discriminate I. typographus infestation levels using regressions and linear discriminant analyses.Across the various I. typographus infestation levels, we found significant differences (p < 0.05) in gravimetric water content, but not in equivalent water thickness due to the latter statistic's high correlation with leaf density. The results show correlations between the lidar intensity metrics and several infestation symptoms: defoliation, discoloration and resin flow. The intensity metrics explain 50% of the variation in the infestation severity (as determined in the field based on canopy and stem symptoms). The overall accuracy with three infestation classes (no, low, or moderate) was 66%, but the overall accuracy with two infestation classes (not infested, or infested) was 90%. The classifiers combine lidar intensity metrics from the stem and the canopy to allow for the detection of bark-beetle infestations in the early, so called green-attack stage. The intensity metrics explain part of the variations in tree-level gravimetric water content and equivalent water thickness, with adjusted R2 values of 0.48 and 0.68, respectively. Terrestrial dual-wavelength lidar shows potential for providing objective tree-decline measurements at tree level: this method can be further used to enhance forest inventories and automate tree-vigor data collection, which has traditionally required expert knowledge.

Characteristics of brown leaf rust virulence on winter durum wheat varieties in the Rostov region

The purpose of this work was to characterize the virulence of the P. triticina population on durum wheat in the Rostov region and to assess the leaf rust resistance in the promising winter durum wheat varieties selected by the “ARC “Donskoy”. The joint studies were conducted in the laboratories of FSBSI “Agricultural Research Center “Donskoy” and FSBSI All-Russian Research Institute of Plant Protection. The samples of pathogen populations were collected on durum wheat varieties “Donchanka”, “Lazurit”, “Donskoy Yantar” and “Prikumskaya 142” and propagated on the susceptible soft and durum wheat varieties in the laboratory. There were studied 64 mono pustular isolate. The studied isolates were avirulent to the Thatcher lines with the genes Lr2a, Lr2b, Lr2c, Lr9, Lr15, Lr16, Lr19, Lr20 and Lr24 and were virulent to Lr3a, Lr3bg, Lr3ka, Lr10, Lr11, Lr14a, Lr14b, Lr18, Lr26, Lr30 и Lr44. All samples of populations propagated on durum wheat were characterized by avirulence to the TcLr17 line, and those propagated on soft wheat were mainly characterized by virulence. In general, the conducted analysis revealed significant differences in the composition of pathogen populations on durum and soft wheat. The isolates from durum wheat had a significantly smaller number of virulence alleles, compared with the isolates from soft wheat. In addition, there were observed differences in the latent period of isolates developing on soft and durum wheat (it was less on soft wheat). In 2015-2017 there were studied 17 varieties of winter durum wheat in the laboratory and field conditions. The variety “Arena” and line KS-586/13 were characterized with a high level of resistance in the field (0-5% of infestation) and laboratory conditions (score 0-2). There were identified the weakly susceptible varieties “Yubilyarka”, “Lazurit”, “Kurant”, “Aksinit”. A moderate infestation throughout all years of study was established on the varieties “Yakhont”, “Terra”, “Diona”, “Kristella”, “Agat Donskoy” (10-20%). The variety “Donchanka” (50-60% in 2015-2016; 40-50% in 2017) belongs to the susceptible group. The varieties “Donskoy Yantar”, “Gelios”, “Yantarina” and “Amazonka” were of medium susceptibility (20-40%).

Impact of Lygus hesperus (Hemiptera: Miridae) Feeding and Oviposition on Lettuce

The western tarnished plant bug, Lygus hesperus Knight (Hemiptera: Miridae), is an important insect pest of lettuce, Lactuca sativa L. in the central coast region of California. However, little is documented on the injury symptoms relative to levels of L. hesperus infestation on lettuce. Experiments were conducted in which lettuce plants were exposed to 0, 1, 3, 5, and 10 L. hesperus adults for 2 and 7 days. The major injury symptom observed was lesions on the midrib of the leaves, and under low to moderate infestation (e.g., one to five adults per plant) after 2 days of exposure these lesions were not significantly different from the insect-free control. Under heavy infestation (e.g., 10 adults per plant), however, lesions developed rather quickly after 2 days of exposure. The number of lesions was positively associated with numbers of feeding sites and eggs. When heavy infestation lasted for a week, most of the plants died. At low to moderate infestation, more lesions developed compared with the insect-free control. After a weeklong exposure, an increase in number of lesions was negatively associated with plant height. The results emphasize the need for regular scouting to facilitate immediate management decisions and actions to reduce losses from L. hesperus feeding and oviposition injury in lettuce.

Geostatistical Analysis of Spatial Distribution of Endoclita signifer Larvae on Eucalyptus

Endoclita signifer is a native wood borer species adapted to infest Eucalyptus in Guangxi of China. To better understand its spatial distribution in Eucalyptus forests, geostatistical approach was employed to analyze survey data of small scale (plantation level) and large scale (provincial level). The small scale results showed that the spatial distribution pattern was clumped regardless of infestation level. But the distance of spatial dependence was different with different infestation levels. These distances were 20.0 m, 40.3 m and 69.4 m for light, moderate and severe infestation levels, respectively. This indicated that as infestation level increased, the spatial distribution was less clumped. At the large scale level, the spatial distribution pattern was random when infestation was light. At the moderate and severe infestation level, the distribution pattern was clumped. The distance of spatial dependence was 43.6 km, 15.5 km and 12.47 km for light, moderate and severe infestation, respectively. This trend was opposite to that of the small scale. The large scale survey results reflected the occurrence of E. signifer in Guangxi province. Eucalyptus trees are cultivated in every county of Guangxi. Plantations with light infestation were scattered in a random pattern across the province. Moderate and severe infested plantations were mainly distributed in the central and southern areas of the province where Eucalyptus cultivation has longer history compared to other areas. Furthermore, the distance of spatial dependence was 17.4 km and 21.3 km for the 2nd generation forests (ratoon) and the 1st generation forests (established via seedlings), respectively. The observed spatial distribution patterns of E. signifer larvae seemed closely related to its biology and its successful adaptation to attack exotic Eucalyptus. These results provide fundamental knowledge for forecasting and evaluating E. signifer infestation and damage of Eucalyptus forests.

A survey of potato growers in Bangladesh: production and challenges

The study was conducted in the 20 upazila of 10 selected major potato growing districts of Bangladesh to find out the present potato cultivation status, challenges, diversity of pests and their risks management options among the farmers. The data were collected through interview of 500 potato farmers considering 25 potato farmers from each upazila. Infections of diseases were reported to be the major problems followed by lower market price of the produced potato. Other major problems faced during potato cultivation were insect pest attack and weed attack. The BARI Alu-7 (Diamant) was most susceptible potato variety to insect pests and diseases, whereas the Lal-pakhri was the least susceptible to pests. Most of the fields (98.50%) were infested by cutworm. Among these pests, cutworm and aphid were identified as major pests and caused high and moderate infestations respectively. Others were identified as minor pests of potato with low infestations. Potato tuber worm was found as the key pest in storage condition. Rat was reported as the most infesting vertebrate storage pests. Currently cutworm and aphid were more damaging insect pest of potato in field condition than previous infestation, and potato tuber worm was more damaging insect pest in storage. Insecticide spray is the most favorable pest control method among the potato growers. Only a little portion of farmers have knowledge about integrated pest management (IPM) practices. So, it is expected the proper awareness program and planning will be taken to handle such challenges.Res. Agric., Livest. Fish.5(2): 165-174, August 2018

The implications of red rice on food security

Due to its genetic similarity with commercial rice, red rice is one the most damaging weeds in direct seeding rice systems. Using an integrated approach to estimate the economic, environmental, and food security impact of red rice infestation in the U.S. as an empirical case study, we find that losses under a moderate infestation scenario from 2002 to 2014 amount to 5.7 million tons or 6%, with an environmental cost of $457 million. The resulting production loss in the U.S. is enough to feed 12 million additional people a year. We extend these findings to selected Asian countries where adoption of direct rice seeding is increasing, and estimate that red rice can have significant impacts on global food security.

Impact of Biocide, Insecticides, Compost and Mineral Fertilizers Treatments on the Abundance of Parasitoid and Predator Insects in Rice Fields

The present study was designed to investigate the effect of rice straw compost, recommended mineral fertilizers, Organic Insecticides and chemical Insecticides on the abundance pattern of natural enemies in rice ecosystems. To maximize rice productivity, rice growers tend to use chemical fertilizers and pesticides particularly to control different pest species, regardless of damage levels. Accordingly, rice fauna of natural enemies is severely impaired, leading to unbalanced rice ecosystems. The current investigation was carried out at the experimental farm of Rice Research and Training Center (RRTC), Sakha, Kafr El-Sheikh during 2016 and 2017 rice seasons. Using both D–Vac machine and pit–fall traps, parasitoids and predator insects were surveyed. Twelve hymenopterous parasitoid species were surveyed. Most of the parasitoid species were found belonging to Mymaridae, Trichogrammatidae and Braconidae. Twenty insect predator species, related to 13 families and seven orders, were identified, most of which are belonging to Coleoptera and Hymenoptera. Also this study aimed to surveying natural enemies (parasitoids and predator insects) and the effect of compost as an organic fertilizer on population densities of such beneficial insects. Although the application of insecticides successfully controlled insect pests, these chemicals have almost eradicated (more than 90 % reduction) the natural enemies. Biocide applications, especially Achook (Neem) and Tracer, achieved a considerable insect pest control, with population reductions of 33.30-57.32 and 10-46.01%, respectively. Unfortunately, the evaluated biocides induced mortalities to the considered natural enemies, but with too much less levels than did the insecticides. The current results indicate that the biocides could be applied to control rice insects in case of moderate insect infestations, with taking into consideration that they are not completely safe to the beneficial insects.

Infestation and population dynamics of striped flea beetle Phyllotreta striolata Fabricius in cruciferous vegetables in Kashmir

Field surveys to study the infestation and population dynamics of the most abundant striped flea beetle, Phyllotreta striolata Fabricius, on two abundantly grown cruciferous crops viz., kale (Brassica oleraceae L. var.acephala) and turnip (Brassica rapa L.) revealed that these suffered with moderate and severe infestation, respectively. The maximum infestation was at cotyledonary stage as compared to true leaf stage. The pooled data of two year study revealed the maximum mean % infestation, severity, and number of flea beetle catches/sweep on turnip as compared with kale. Southern zone revealed the highest mean % infestation, severity and number of beetle catches/sweep followed by the Central and Northern zones. The extent of damage, severity and population build-up was more during 2012 compared to 2013. Emergence of the overwintering generation started from the second fortnight of March up to the end of May in kale while the subsequent generations started emerging at the beginning of June and the maximum trap catches were obtained during the second fortnight of July i.e. from 27th to 29th standard weeks and the minimum catches by the end of October. In turnip, the pest started its activity in the first week of August i.e. from 32nd standard week, immediately after sowing and remained active until end of October. Maximum catches of flea beetles were observed in the second fortnight of September i.e. in the 38th standard week and thereafter it decreased to its lowest during the end of October. The study further revealed that the temperature influenced the activity of the flea beetles significantly.