NITIDÚLIDOS (COLEOPTERA: NITIDULIDAE) EN CAMPOS DE FRESA FRAGARIA VESCA LINNAEUS EN LAS LOCALIDADES DE AUCALLAMA, HUARAL Y SUPE, BARRANCA EN LIMA, PERÚ

En el cultivo de fresa con tecnología tradicional, los nitidúlidos causan una merma mínima en postcosecha al estar asociados a frutos sobremaduros. Los nitidúlidos fueron colectados durante diciembre 2018 y enero 2019, en campos del distrito de Aucallama (Huaral) y Supe (Barranca), Perú. Se registraron y determinaron un total de 54 individuos, 2 subfamilias, dos géneros y dos especies. La especie con mayor incidencia fue Lobiopa insularis (Castelnau, 1840), con el 81% de especímenes colectados. Las otras especies registradas fueron: Carpophilus hemipterus, Carpophilus sp.1 y Carpophilus sp.2.

Emigration Effects Induced by Radio Frequency Treatment to Dates Infested by Carpophilus hemipterus

The dried fruit beetle (Carpophilus hemipterus) is considered a key pest of dates, infesting fruits both in the field and during storage. Control measures against the species rely on the use of chemicals or heat treatments based on sunlight, hot air or radio frequency (RF) applications. Previous investigations that have aimed to define control procedures for a total disinfestation using RF treatments with different exposure durations have shown the typical behavior of adults in some trials, which, under the influence of temperature increases, started to escape from infested fruits. We focused on the application of different RF voltage-time combinations to induce the emigration of C. hemipterus adults from dates in order to produce a complete disinfestation. The results showed that the application of 2500 V RF for 8–10 min to infested dates resulted in nearly 100% of adults escaping from fruits, thereby cleaning the commodity with low or no mortality inside and outside the dates. These achievements provide a new strategy for controlling key insect pests of dates that could be applied at an industrial scale, allowing for the quick disinfestation of fruits without affecting the fruit with harmful substances, such as residues from chemical treatments, and without unwanted side effects on date quality.

Fecundity and survival of Carpophilus hemipterus (Linnaeus, 1758) (Coleoptera: Nitidulidae) on alternative hosts

The tendency of the dried fruit beetle Carpophilus hemipterus (Linnaeus, 1758) (Coleoptera: Nitidulidae) to occur as pests in stores and fields has necessitated investigations on its fecundity and survival on some alternative food hosts such as groundnut, cocoa, cowpea and rice. Two copulating pairs of the adult beetle were introduced on fifty grammes of each food substrate in a no choice test at 28 oC +/- 3 oC and relative humidity of 75% +/- 5%. The number of eggs laid, emerged larvae, and enclosed adults were recorded. Weight loss of the food substrates was also recorded. Analysis of variance was performed on the data generated. Kaplan Meier analysis was carried out to determine the beetle survival rate on each host. Fewer eggs were deposited on rice compared to the other hosts; however, there was no significant difference (p > 0.05) between the percentage hatchability of the beetle on all the food hosts. As evidenced by the larvae emergence data, cocoa (4.28%) and groundnut (5.42%) suffered significantly higher (p < 0.05) levels of damage. However, based on the Kaplan Meier survival index (Px), it was noted that the adult enclosion and survival of the beetle was lowest on cocoa (0.27) and highest in cowpea (0.64). General Linear Model (GLM) revealed highly significant influence (p < 0.0001) of food substrate (S) on the fecundity of C. hemipterus (F3,320 = 464.099) and its larvae development (F3,199 = 345.042). It also showed the effect of Period (P) on number of eggs (F3,320 = 320.932) and larvae development (F3,199 = 188.167) to be highly significant (p < 0.001). Likewise, there was significant impact (p < 0.0001) of the interaction of food substrate x duration (S x D) on the oviposition of C. hemipterus (F9,199 = 5.167) and larvae development (F9,199 = 13.403). The ability of C. hemipterus to survive on less preferred food hosts is highlighted in this study.

JENIS DAN POPULASI SERANGGA HAMA PADA BERAS DI GUDANG TRADISIONAL DAN MODERN DI PROVINSI GORONTALO

ABSTRACT The quality and quantity of rice as a source of food for most of Indonesian people are closely connected with the activity of insect pests in Warehouse. This study aims to determine the species and insect pests populations on Rice at Traditional and Modern Warehouse in Province of Gorontalo. The study used a survey method shelter/rice warehouse in Mootilango district, Boliohuto District, and Tolangohula district, Gorontalo province. Sampling was conducted in a purposive sampling is to take a sample of the suspected rice pests. Sampling was carried out 4 times with a time interval of 2 weeks. The research found six species of insect pests on rice commodities in Gorontalo regency consisting of 5 species of the order Coleoptera and 1 type of the order Lepidoptera. The results show that the identification of insect pests found are Sitophilus oryzae (Coleoptera; Curculionidae), Tribolium castaneum (Coleoptera: Tenebrionidae), Carpophilus hemipterus (Coleoptera: Nitidulidae) Oryzaephilus sp. (Coleoptera; Silvanidae), Ahasverus sp. (Coleoptera; Cucujidae), Corcyra cephalonica (Lepidoptera; Pyralidae). Average highest pest insect populations, respectively S. oryzae (54.60 individuals), Tribolium sp. (13.85 individuals), Oryzaephilus sp. (4.52 individuals), Ahasverus sp. (3.42 individuals), Corcyra sp. (2.42 individuals) and C. hemipterus (6.94 individuals), while the highest populations of insect pests found in traditional 16.40 modern warehouses 12.34 individual Keywords : insect pests, rice, traditional and modern werehouse