Journal of Applied Entomologist

Assemblage of spiders diversity - an agent of biological control of agricultural pests

2023-01-03T16:16:11+00:00

Arachnids provide an important service by keeping insect populations under control. Spiders are acting as an agent of biological control of insects; without them many insects would have reached high level of pest proportions. This present investigation was aimed to attain the diversity of spider fauna of cultivated croplands of Swamimalai Region of Cauvery Delta, Tamil Nadu. The data on diversity of spiders was investigated by hand picking method. The spotted spider specimens were photographed and left in the same environment without disturbing it. A total of 31 species of spiders under 13 genera were recorded in buildings, wooded areas and cultivated regions. Spiders are normally built nests on their living habits for dwelling as well as catching prey which are trapped in their nests. This is only the baseline study but it needs a long-term inventory which will fulfill the lacunae of spider diversity in the study area.

Insect pests of important fruit crops and their recent management strategies in emerging horticulture hub of Andhra Pradesh-Ananthapuramu

2022-11-18T05:41:14+00:00

The ‘Mission Horticulture Hub’ envisaged by Andhra Pradesh government to develop the Ananthapuramu district with a semi-arid climate registering an annual rainfall of less than 500 mm is catching up among the farmers despite the adverse climatic conditions and groundnut being its principal crop. Farmers keen on shifting from groundnut cultivation to raising fruit gardens as it is proving remunerative. Mango plantations are spread over 40,000 hectares, sweet oranges 40,000 hectares, banana 10,000 hectares, pomegranate 10,000 hectares, grape 500 hectares and vegetables in 30,000 hectares apart from sapota, guava and papaya in considerable extent. For efficient fruit production, the insect-pest poses a major challenge. Citrus, Pomegranate, Guava and Banana receive more attention.

Efficiency of entomopathogenic nematode and certain bio-agents as biological control against the tow-spotted spider mite, Tetranychus urticae Koch

2023-02-05T19:33:57+00:00

The objective of this study was to assess the efficiency of biocontrol agents such as entomopathogenic nematodes (EPNs) Heterorhabditis bacteriophora and Steinernema carpocapsae to Abamectin against the two-spotted spider mite Tetranychus urticae under laboratory settings. The mortality percentages of H. bacteriophora were 13.33 to 26.66% and 10 to 23.33% when using 2000 and 1000 juveniles, respectively. Moreover, mortality percentages from 6.6 to 26.66% for S. capocapsae were identical for both two levels. In contrast to Abamectin, Bioarc (Bacillus megaterium), Biozeid (Trichodema album), and Baroque agents were tested against T. urticae under greenhouse conditions. Bioarc had the highest mean reduction (96.28%) compared to Abamectin (99.16%), although Biozeid and Baroque were approximately equivalent in terms of mortality reduction (95.48% and 95.2%, respectively).

Foraging and pollination effectiveness of Apis mellifera (Hymenoptera: Apidae) on Vigna unguiculata (L.) Walp. 1843 (Fabaceae) in Yaounde-Cameroon

2023-02-15T18:10:17+00:00

Experiments were made in Yaoundé to determine the effects of Apis mellifera visit on the pollination and the productivity of cowpea, Vigna unguiculata. Two treatments for each experiment were used on 40 randomly-selected plants each. These included Autonomous Self-Pollination (ASP) with flowers from which insects visit, with airborne pollen flow excluded (treatments 1 and 3), flowers that received a single bee visit (SBV) of A. mellifera (treatments 2 and 4). This honey bee mainly foraged for nectar and pollen resources. The mean foraging speed was 11.55 flowers/min and the duration of visits was 10.94 sec to collect nectar and pollen. All flowers produced pod with or without insect visits. Apis melliferai was effective pollinator, and of course their visits increased pod production (fruiting rate), number of seeds (number of seeds/pod) and normal seed (percentage of normal seed). Apis mellifera foraging resulted in a significant increment of the fruiting rate by 31.18 %, as well as the number of seeds/pod by 29.97 % and the percentage of normal seeds by 15.46 % in the two years in Yaounde. Conservation of A. mellifera colonies close to V. unguiculata fields could be recommended to increase pod and seed production in the region.

Evaluation of larvicidal, pupicidal and adulticidal activities of three plants against filarial vector Culex quinquefasciatus Say (Diptera: Culicidae)

2023-03-03T15:29:32+00:00

Mosquitoes are the most annoying creatures on the planet, causing the spread of deadly diseases such as malaria, filariasis, dengue fever, yellow fever, and Japanese encephalitis. The major purpose of the present finding is to evaluate the mosquito larvicidal activity of the flowers of Senna sophera L. and the leaves of Mammea americana and Dieffenbachia seguine against Culex quinquefasciatus. The fresh plant parts of three plants were collected and tested at different concentrations. All the graded concentrations of three plant parts, i.e., 0.5 ml, 0.6 ml, 0.7 ml, 0.8 ml, 0.9 ml, and 1 ml, showed significant larval mortality. The lowest LC₅₀ value calculated was 0.45 ml, 0.53 ml, and 0.68 ml of flower extract of S. sophera and crude leaf extract of M. americana and D. seguine, respectively. The crude extracts of both leaves and flowers also showed pupicidal and adulticidal activity with LC₅₀ values of 5.83 ml, 6.67 ml, and 5.68 ml; 2.81 ml, 2.34 ml, and 1.14 ml, respectively. The qualitative phytochemical tests are done in the laboratory. The result of phytochemical analysis indicates the presence of secondary metabolites such as saponin, alkaloid, glycoside, carbohydrate, and protein in the crude extract of the tested plant parts of three plants. The dead larvae were also examined under a compound microscope to determine the possible reason for their deaths. The results support the idea that the tested plant extracts can be used for the control of larval and adult life forms of Culex quinquifasciatus.

Contribution to the study of the Pyraustinae Meyrick, 1890 (Lepidoptera, Crambidae) on the Arabian Peninsula: a new species of Psammotis Hübner, 1825 from Saudi-Arabia and new distributional data on four described species

2023-02-20T19:42:14+00:00

Taxonomic and faunistic results on six genera of the Pyraustinae (Lepidoptera, Crambidae) are presented on the basis of material collected in SW Saudi Arabia (Hejaz, Asir and Fayfa mountains) and in Dhofar, the south-western province of Oman. A new species of the genus Psammotis Hübner, 1825, Psammotis rubrilinearis sp. nov. is described. The adults, the male and female genitalia and the tympanal organs are described and figured. The new species is placed closed to Psammotis pulveralis (Hübner, 1796), Psammotis roseus Maes, 2014 and Psammotis rubrivena (Warren, 1892) on the basis of shared character states in the male and female genitalia. The differential character states in wing maculation and morphology are listed. The presence of the genus Psammotis Hübner, 1825 is reported as new to the entomofauna of the Arabian Peninsula. New distributional records are given for four described species of the subfamily. The presence of Achyra nudalis (Hübner, 1796) in Saudi-Arabia is re-confirmed. Palepicorsia ustrinalis (Christoph, 1877) and Uresiphita gilvata (Fabricius, 1794) are reported as new for Oman. Pioneabathra olesialis (Walker, 1859) is reported as new for Saudi-Arabia. The current taxonomic status of the Arabian populations of Pioneabathra olesialis (Walker, 1859) is reconfirmed by means of DNA-Barcoding. The male and female genitalia of Achyra nudalis (Hübner, 1796) and Pioneabathra olesialis (Walker, 1859) and the male genitalia of Palepicorsia ustrinalis (Christoph, 1877) are figured.