scholarly journals The occurrence of fungal and insect pests in riparian stands of the central Hron and Slatina rivers

2012 ◽  
Vol 52 (No. 1) ◽  
pp. 22-29 ◽  
Author(s):  
J. Kodrík ◽  
M. Kodrík ◽  
P. Hlaváč

The paper deals with the occurrence of fungi and rusts, viruses and insects on main woody species in riparian stands along the middle courses of the Slatina and Hron rivers in Slovakiain 2002–2004. Forty fungal species, rusts and viruses and 79 insect species were found. The highest number of fungi occurred on the branches and twigs of poplar where Cryptodiaporthe populea (Sacc.) Butin and Phellinus igniarius (L.) Quél. had the highest representation and so the influence on the health condition. Melampsora alliipopulina Kleb., Poplar mosaic carlavirus, Venturia po-pulina (Vuill.) Fabr. and Venturia tremulae Aderh dominated on the leaves. The most frequently present fungus on the aspen was Armillaria sp., Phellinus igniarius (L.) Quél., on the alder a new hybrid from the genus Phytophthora – alder Phytophthora, Valsa oxystoma Rehm., Inonotus radiatus (Sowerby) P. Karst. and Inonotus obliquus (Fr.) Pilát. From the insect species Melasoma vigintipunctata Scop. and Phyllodecta vitellinae L. caused total defoliation on willows. The highest occurrence on the black poplar was on the leaf stalks represented by Pemphigus spirothecae Pass. species, on the alder it was Cryptorrhinchidius lapathi L. on the twigs and Agelastica alni L. on the leaves.

2019 ◽  
Vol 56 (Special) ◽  
pp. 143-155
Author(s):  
SD Mohapatra ◽  
R Tripathi ◽  
Anjani Kumar ◽  
Suchismita Kar ◽  
Minati Mohapatra ◽  
...  

The insect problem is accentuated in intensive rice cropping where the insects occur throughout the year in overlapping generations. Over 800 insect species damaging rice in one way or another, although the majority of them do very little damage. In India, about a dozen of insect species are of major importance but the economic damage caused by these species varies greatly from field to field and from year to year. Insect pests cause about 10-15 per cent yield losses. Farmers lose an estimated average of 37% of their rice crop to insect pests and diseases every year. This review focuses on precision farming tools being used in rice pest and diseases management viz., forecasting model for real-time pest-advisory services, hyper-spectral remote sensing in pest damage assessment, computer-based decision support system, disruptive technologies (mobile apps).


2016 ◽  
Vol 31 (1-2) ◽  
pp. 9-18 ◽  
Author(s):  
Zlatko Korunic

Despite numerous advantages of diatomaceous earth (DE), its use for direct mixing with grains to control stored-product insects remains limited because of some very serious obstacles and disadvantages. The main obstacles preventing a wider use of DEs for mixing with grain, such as health concerns, the reduction in bulk density, differences in insect species tolerance to the same DE formulation, the effects of grain moisture and temperature on the effectiveness against insects, the influence of various commodities on DE efficacy, the use of DEs in some other fields, and possible solutions for overcoming DE limitations during direct mixing with grains are described in this manuscript. The same attempts have been made to discover new ways of increasing significantly the effectiveness against insects when much lower concentrations are used for direct mixing with grains. If these newer enhanced formulations can respond to the existing limitations of diatomaceous earth, a wider utilization of diatomaceous earth may be expected to control stored-product insect pests.


2020 ◽  
Vol 15 (2) ◽  
pp. 41-57
Author(s):  
Fatma Acheuk ◽  
◽  
Kemais Abdellaoui ◽  
Wassima Lakhdari ◽  
Nora Chahbar ◽  
...  

The insecticidal potential of the Saharan plant Cotula cinerea, was evaluated on two insect species namely Aphis fabae and Tribolium castaneum by topical application (contact toxicity) and repellency test. A crude ethanolic extract of aerial part of the plant was prepared and tested in the laboratory on adults of both species. For contact toxicity, five doses were tested on each of the two species 1.56, 3.12, 6.25, 12.5 and 25 mg/ml for A. fabae and 25, 50, 250, 350 and 500 µg/insect for T. castaneum. The repellency of the extract was studied at the dose 500 μg/insect for T. castaneum and 25 µg/ml for A. fabae. Results showed that the repellency of the extract increased with exposure time and the highest rates were observed after 4 h of exposure (72.33 ± 22% for T. castaneum and 87 ± 3.6% for A. fabae). For insecticidal activity, at the highest doses (25 mg/ml and 500 µg/ml), 100% mortality is obtained 72 h after treatment for A. fabae and after 48 h for T. castaneum. The extract of this plant was found to be more toxic against T. castaneum adults. LD50 calculated 24 h after treatment for the two species is estimated at 1.7 mg/ml for A. fabae and at 30.3 µg/insect for T. castaneum. The extract of this plant inhibited the activity of acetylcholinesterase (AChE) in both insect species. This result suggests that this plant has a neurotoxic effect on A. fabae and T. castaneum. The results of phytochemical study showed that the plant is mainly rich in flavonoids, gallic tannins, alkaloids, saponosides and glucosides. The insecticidal effect obtained in this study could be due to the synergetic action of all constituents of the extract. Results suggest the possibility of using the extracts of this plant in integrated pest management to replace the chemical insecticides.


2019 ◽  
Vol 30 (2) ◽  
pp. 106-112
Author(s):  
T. M. Kolombar

Annually in the world, insect pests kill 10–15 % of the crop yield, which in the face of increasing humanity creates a global problem for food security. For the territory of Ukraine in some years, the loss of wheat yields reach 25 % and, in the face of this tendency, real risks to the security of the state are created. Considering that the agrarian trend of the state development has been increasing in recent years, the development of grain-adapted to the ecological and climatic conditions of Ukraine is a priority direction of the development of domestic agriculture. And the development of new environmentally friendly methods of controlling pests of wheat using parasitic organisms will become a fundamentally new and pressing issue in the development of organic production in the country. The general list of pest species that can cause serious wheat yield and forage reduction in Ukraine includes more than 230 names, but only 18 species are able toentail the biggest losses. Among them belong to the order Coleoptera. One insect species is usually a host of several species of mites, nematodes and up to ten species of gregarines and microsporidia. Unfortunately, the taxonomic composition of parasites of phytophagous pets of wheat in Ukraine has not been thoroughly investigated. We studied the interrelation between parasites of 4 phytophagous insects of wheat as well as of 14 insect species found in granaries. The study of the species composition of parasitic organisms of wheat and grain pests is based on the study of the elementary part of the consortium ecosystem, where they act as second order consortia. Phytophagous parasites of wheat and collar pests of cereals, as second-order consorts, have been fragmented worldwide. The purpose of this work is to determine the species composition of gregarine as a component of wheat consortium for their further use in the creation of integrated methods of protection of wheat and products of its processing. As a result, 28 species of gregarines were registered, which belong to seven families (Didymophyidae, Ophryocystidae, Hirmocystidae, Lipotrophidae, Stylocephalidae, Actinocephalidae and Gregarinidae). On the average, 1–2 species of gregarines parasitize in one pest species. 7–10 species of parasites were identified in some insects of the family Tenebrionidae (Tenebrio molitor Linnaeus, 1758 and Tribolium confusum Jacquelin du Val, 1863). Each presented parasite is characteristic of 1–2 species of pests, but there are species of gregarines that infect up to four species of model species, such as Gregarina cuneata Stein, 1848. The largest number of individuals who are infested with gregarines belong to such families as Tenebrionidae and Dermestidae (38,6 % and 36,0 % of the total number of species, respectively). On pests – phytophages parasitizes about 8 species of gregarine families Stylocephalidae, Gregarinidae, Actinocephalidae. For barns pests are recorded barnacles of all 7 families.


1978 ◽  
Vol 9 (5) ◽  
pp. 204-208 ◽  
Author(s):  
M Bengston

Though most of the important insect pests of stored grain occur in Australia, and conditions are ideal for their development, insect control since the introduction of malathion has been so effective that Australian Federal legislation now requires that grain for export must be totally insect-free. The appearance of resistance to malathion in 1968 and its subsequent development in most grain-insect species, however, emphasises the need for alternative safe and effective grain protectants.


2019 ◽  
Vol 41 (4) ◽  
Author(s):  
Nguyen Thi Oanh ◽  
Nguyen Kim Bup ◽  
Khuat Dang Long

 The eulophid wasp, Anselmella malacia Xiao & Huang, 2006 (Hymenoptera: Eulophidae), is reared from fruits of the water apple, Syzygium samarangense, and is reported as an important phytophagous developing as seed-eaters of Syzygium species in Malaysia. Analysing specimens of pest insects infested inside of pear-shaped fruits of the cultivated water apple, S. samarangense, in Dong Thap Province, South Vietnam, a total of four insect species were recorded as the important pests for fruits of six varieties of the cultivated water apples. The hymenoteran wasp, A. malacia, is recorded for the first time from Vietnam. Further evidence is needed to prove A. malacia being an invasive pest in Vietnam. The associated hymenopteran parasitoid assemblage with the fruit infested insect pests is also provided. 


2020 ◽  
Author(s):  
Haibo Bao ◽  
Haoli Gao ◽  
Jianhua Zhang ◽  
Haiyan Lu ◽  
Na Yu ◽  
...  

AbstractMethane emitted by insects is considered to be an important source of atmospheric methane. Here we report the stimulation of methane emission in Periplaneta americana, an insect species with abundant methanogens, by neonicotinoids, insecticides widely used to control insect pests. The application of cycloxaprid (CYC) and imidacloprid (IMI) caused foregut expansion in P. americana, and increased the methane production and emission. Antibiotics could mostly eliminate the stimulatory effects. In P. americana gut, hydrogen levels increased and pH values decreased, which could be significantly explained by the gut bacterium community change. The proportion of several bacterium genera increased in guts following CYC treatment, and four genera from five with increased proportions could generate hydrogen at anaerobic conditions. Hydrogen is a central intermediate in methanogenesis. Gut methanogens could use the increased hydrogen to produce more methane, especially at acidic conditions. Following neonicotinoid applications, all increased methanogens in both foregut and hindgut used hydrogen as electron donor to produce methane. Besides, the up-regulation of mcrA, encoding the enzyme that catalyzes the final step of methanogenesis, suggested an enhanced methane production ability in present methanogens. In the termite Coptotermes chaohuensis, another methanogen-abundant insect species, hydrogen levels in gut and methane emission significantly increased after neonicotinoid treatment, which was similar to the results in P. americana. In summary, neonicotinoids changed bacterium community in P. americana gut to generate more hydrogen, which then stimulate gut methanogens to produce and emit more methane. The finding raised a new concern over neonicotinoid applications, and might be a potential environmental risk associated with global warming.


2021 ◽  
Vol 58 (Special) ◽  
pp. 168-193
Author(s):  
SD Mohapatra ◽  
Amrita Banerjee ◽  
RK Senapati ◽  
G Prasanthi ◽  
Minati Mohapatra ◽  
...  

Insect pests and diseases are the major biotic constraints in rice production. According to the ecosystem, the incidence of insect pests and diseases vary. The degree of loss due to different biotic stresses differ widely depending upon the predominant factors of abundance of these pests in a particular year, season or locality. Though around 800 insect species damaging rice in one way or another, the majority of them do very little damage. In India, about a dozen of insect species are of major pest status. Farmers bear an estimated average of 37% losses in rice crop due to insect pests and diseases every year. This review focuses on status of insect pests and diseases, extent of losses, different tools used in pest monitoring and management in rice. Among the important pest management tools used in rice pest and diseases management are forecasting model for real-time pest-advisory services, light trap, hyper-spectral remote sensing, computer-based decision support system, disruptive technologies (mobile apps).


2013 ◽  
Vol 46 (3) ◽  
pp. 97-101 ◽  
Author(s):  
Samuel Adelani Babarinde ◽  
Grace Oluwakemi Babarinde ◽  
Adeola Foluso Odewole ◽  
Olubukola Omotoyosi Alagbe

Abstract A survey was carried out between March and August 2010 to identify insect pests of stored yam chips in Ogbomoso Metropolis, Nigeria. Dried yam chips were randomly obtained from old stocks in 6 local markets within the metropolis on monthly basis. There was a significant (P < 0.05) difference in insect abundance based on month of sampling and insect species. Dinoderus porcellus (Coleoptera: Bostrychidae) was the most abundant species. Other species encountered were Araecerus fasciculatus (Degeer) (Coleoptera: Anthribidae), Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae) and Tribolium castaneum Herbst (Coleoptera: Tenebrionidae). When chips were infested with Dinoderus porcellus and stored for 3 months, reconstituted thick paste (amala) was made from the flour and was evaluated for consumers’ acceptability. Sensory characteristics such as odour, colour, texture, appearance, taste and overall acceptability were significantly (P < 0.05) affected when compared with the paste prepared from the uninfested chips.


2010 ◽  
Vol 45 (Special Issue) ◽  
pp. S53-S62 ◽  
Author(s):  
Z. Laštůvka

Insect pests, as widely tolerant and adaptable organisms, may be less distinctly affected by climate change than other insect species. The changing climate may affect the occurrence and impact of the native pests both negatively and positively (increased importance of thermophilous and xerophilous species and decreased importance of psychrophilous ones, noxious abundances of several species also in higher altitudes, decrease of many pests by frost-free winters, low humidity, weather extremes, increased numbers of antagonists, and phenological discrepancy with the host plant). Expansions of new pests into the territory of the Czech Republic, caused by climate change, will be very limited. A small number of greenhouse pests may be expected to occur in outdoor conditions. Increased temperatures may cause a slight increase of non-indigenous invasive insect species and migratory pests. In Central Europe the climate change will intensify the effects of other factors. In the next 20–50 years, the changes in species composition and importance of insect pests of plants will be caused by factors in the following order: (l) introductions of non-indigenous species, (2) new approaches in pest control, (3–4) changes in crop cultivation and representation of crops, (3–4) climate change, (5) other causes (unexpected shifts of ranges, changes in food preferences of insect species, etc.).


Sign in / Sign up

Export Citation Format

Share Document