Evaluation of Quality of Trichogramma chilonis Ishii from Different Production Units in India (original) (raw)
Related papers
Effects of Parasitoid and Host Egg Age on Parasitism by Trichogramma Chilonis (Ishii)
ird.sut.ac.th, 2002
Ishii (Hymenoptera: Trichogrammatidae) as influenced by host egg age and age of the female parasitoid was evaluated under the laboratory conditions. An experiment conducted to see the effect of host egg age on parasitism by T. chilonis did not reveal an overall treatment effect (F = 0.95). This implies that T. chilonis does not discriminate between host ages of less than one day. The developmental period of T. chilonis inside the host eggs remains almost the same in both the experiments i.e. 11 days. A second experiment on investigating the effect of parasitoid age on parasitism showed that T. chilonis laid significantly the highest average numbers of eggs at 80.6 + 1.5 and 69.4 + 6.3% during the first 8 and 24 h of its age respectively. Later, the parasitization decreased to 35% by the end of day 4. Thus, for the highest yield of parasitoid production, it is important to use younger Trichogramma for parasitization.
The study was conducted on the biological parameters of Trichogramma chilonis Ishii (Trichogrammatidae: Hymenoptera) feeding on grain moth, Sitotroga cereallela eggs at three constant temperatures and five different ages of host eggs at Insect Pest Management Programme, National Agricultural Research Centre, (NARC) Islamabad. The results revealed that maximum rate of parasitism was 95.70 ± 1.94 at 28 ± 1 °C while minimum was 61.30 ± 1.70 at 32 ± 1 °C. Maximum adult emergence and female ratio from parasitized eggs were 96.30% with 59.2± 5.83 female ratio at 28 ±1 °C while minimum was 51.10% with female ratio of 58.1 at 32±1 °C. The maximum developmental duration (9.6 ± 0.32 days) and adult longevity (4.3 ± 0.38 days) was at 24 ±1 °C while minimum was 7.4 ±0.36 and 2.0 ±0.56 days at 32 ± 1 °C. The results indicate that temperature has a significant effect on the biological parameters of Trichogramma and with increasing temperature developmental duration decreased. Similarly effect of host eggs age indicates that maximum parasitism and adult emergence were 97.40 ± 0.84% and 98.20 ± 0.94% on 2h old eggs while minimum parasitism was 24.6 ± 4.92% and adult emergence was 21.5 ± 1.33% from 72h old eggs. Adult longevity and female ratio was not significantly different at different ages of host eggs. Thus out of three tested temperatures, 28 ±1 °C was more suitable for mass rearing of Trichogramma and feeding 2-12h old eggs for maximum parasitism and adult emergence from parasitized eggs under laboratory condition of 28 ±1 °C.
Journal of Biological Control, 2012
Trichogrammatids are efficient egg parasitoids in rice agroecosystem and two species of Trichogramma viz., Trichogramma chilonis Ishii and T. japonicum Ashmead were reported from several species of rice stem borers and other lepiodpterous pests. Physicochemical variations between the cultivars of crops often interfere with the efficiency of the Trichogramma spp. The response of T. chilonis and T. japonicum to the variations in the volatile profile of rice cultivars was investigated. The results indicated that the parasitization efficiency of both T. chilonis and T. japonicum was influenced by the volatiles of rice cultivars. While in some cultivars, such as Kadamba, MTU-1010, KMT 148, KCP-1, the response of T. chilonis was very high, in some of the cultivars like CTH-1, MTU 1010, VTT-5204, the response by T. japonicum was high. The highest overall response of 83.89 % was recorded in the variety Kadamba by T. chilonis . Volatile profile of the cultivars indicated the presence of 9,12...
Indian Journal of Traditional Knowledge
Maize stem borer, Chilo partellus, is a serious pest of maize in India. Insecticides are not the right choice as larvae feed internally. Moreover, the indiscriminate use of pesticides increases the cost and accounts for health and environmental hazards. Adopting non-chemical methods such as biological control is an important strategy for effective suppression of the pest population. Biological control agents such as egg parasitoids, Trichogramma spp. (Hymenoptera: Trichogrammatidae) substantially reduce the pest population and are widely used against lepidopteran insect-pests. We studied the efficacy of egg parasitoid, T. chilonis against C. partellus in Kharif maize and recorded maximum egg parasitism by T. chilonis when released twice at higher rates (i.e. 1,25,000 and 1,00,000 parasitized eggs ha-1). However, treatments with low release rates (one and two releases @ 75,000 parasitized eggs ha-1 , one release @ 1,00,000 parasitized eggs ha-1) experienced significantly high plant damage and did not provide satisfactory monetary returns. In contrast, treatments with higher release rates (i.e. T. chilonis @ 1,25,000 parasitized eggs ha-1 at 7 and 14 DAG; T. chilonis @ 1,00,000 parasitized eggs ha-1 at 7 and 14 DAG) effectively suppressed plant infestation, dead heart formation and leaf injury by C. partellus. These treatments were statistically comparable with chemical control (dimethoate @ 660ml ha-1 at 7 DAG). It can be concluded that one release of T. chilonis is insufficient, and two releases are required for effective management of C. partellus. T. chilonis provides the best result when released twice @ 1,25,000 parasitized eggs ha-1 at 7 and 14 DAG (B:C ratio=1.42) which is at par with two releases @ 1,00,000 parasitized eggs ha-1 (B:C ratio=1.41). Although pesticide-treated plots (Dimethoate 30 EC @ 660 ml/ha at 7 DAG) provide a satisfactory monetary return, they are not environmentally compatible and ecologically viable for the long run.
Quality assessment of trichogramma parasitoids (Trichogramma spp.) from six Mexican insectaries
There are reports that Trichogramma spp. failed to control the target pest, and poor quality may explain these failures. The first goal of this study was to determine which way of reproduction was practiced by Trichogramma spp. colonies from Mexican insectaries, either sexual or asexual, and the second goal was to determine whether those Trichogramma spp. colonies meet the quality standards suggested by the International Organization for Biological Control/ European Community (IOBC/EC). In March 2010, a letter was sent to 27 Trichogramma spp. producers. Six insectaries agreed to participate and sent dead samples of its colonies, a total of 10 colonies. For statistical analysis these colonies were grouped by species, either Trichogramma pretiosum or T. fuentesi. None of the Trichogramma spp. colonies were infected by parthenogenetic-inducing Wolbachia, i.e., all colonies reproduced sexually. Therefore, quality standards for sexual species were used: sex ratio (proportion females) 0.5, embryonic mortality 20 %, and total fecundity 40 eggs. Among the 10 Trichogramma spp. colonies there was great uniformity in sex ratio, embryonic mortality and total fecundity, i.e., per species there were not statistical differences among colonies. In sex ratio (0.5520.038) and embryonic mortality (21 4.48 %) the nine colonies of T. pretiosum barely fulfilled the minimum standards suggested by the IOBC/EC. Using hind tibia length as a proxy of total fecundity, the fecundity (37.85 eggs) of nine colonies of T. pretiosum and two colonies of T. fuentesi fell slightly below the standard suggested by the IOBC/EC. In México only sexual species of Trichogramma Published as ARTICLE in Agrociencia 48: 321-329. 2014. 322 AGROCIENCIA, 1 de abril -15 de mayo, 2014 VOLUMEN 48, NÚMERO 3
Agrociencia 48: 321-329, 2014
Quality of mass-reared biological control agents is vital. There are reports that Trichogramma spp. failed to control the target pest, and poor quality may explain these failures. The first goal of this study was to determine which way of reproduction was practiced by Trichogramma spp. colonies from Mexican insectaries, either sexual or asexual, and the second goal was to determine whether those Trichogramma spp. colonies meet the quality standards suggested by the International Organization for Biological Control/European Community (IOBC/EC). In March 2010, a letter was sent to 27 Trichogramma spp. producers. Six insectaries agreed to participate and sent dead samples of its colonies, a total of 10 colonies. For statistical analysis, these colonies were grouped by species, either T. pretiosum or T. fuentesi. None of the Trichogramma colonies were infected by parthenogenetic-inducing Wolbachia, i.e., all colonies reproduced sexually; so, quality standards for sexual species were used: sex ratio (proportion females) ≥ 0.5, embryonic mortality ≤ 20 %, and total fecundity ≥ 40 eggs. Among the ten Trichogramma colonies, there was great uniformity in sex ratio, embryonic mortality and total fecundity, i.e., per species there were not statistical differences among colonies. In sex ratio (0.552 ± 0.038) and embryonic mortality (21 ± 4.48 %) the nine colonies of T. pretiosum barely fulfilled the minimum standards suggested by the IOBC/EC. Using hind tibia length as a proxy of total fecundity, the fecundity (37.85 eggs) of nine colonies of T. pretiosum and two colonies of T. fuentesi fell slightly below the standard suggested by the IOBC/EC. In México only sexual species of Trichogramma are mass-reared, but at low host densities asexual species (compared with sexual species) are more effective controlling the target pest. So, Mexican insectary personnel should also rear asexual species, and release one or the other depending of host density.
Sri Lanka Journal of Food and Agriculture, 2015
Use of egg parasitoids is an effective option available for managing lepidopteran pest species through augmentation and release of the parasitoids, particularly the locally available species. As the local egg parasitoids in Sri Lanka are poorly studied, an investigation was conducted to identify the egg parasitoids associated with rice leaf folder (Cnaphalocrocis medinalis Guenee) and cabbage semilooper (Trichoplusia ni Hubner). The host eggs were collected in different geographical locations for different durations in rice (Oryza sativa L.) and cabbage (Brassica oleracea L.) fields. The eggs were incubated until the emergence of host larvae or the adult parasitoid. Emerged parasitoids were preserved in 70% ethanol and subsequently dissected for male genitalia and the permanent slides were prepared using Canada balsam as the mounting media. Identification of specimens was done using taxonomic keys and related literature. Identities were confirmed by the Natural History Museum, London. Two species namely, Trichogramma chilonis Ishhi and T. achaeae Nagaraja and Nagarkatti were found parasitizing T. ni at Dodangolla and Thalatuoya regions in Sri Lanka. The record of T. achaeae is the first country report and T. chilonis had been recorded previously in Sri Lanka. The morphology of male genitalia was described and compared with the original description. Trichogrammatoidea bactrae Nagaraja and T. nana Zehnter were found parasitizing C. medinalis eggs at six sampling sites. The male genitalia of these two species were characterized and compared with the original descriptions.
Trichogrammaegg parasitism ofHelicoverpa armigeraon pigeonpea and sorghum in southern India
Entomologia Experimentalis et Applicata, 1999
Trichogramma spp. (Hymenoptera: Trichogrammatidae) only rarely parasitize eggs of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) on pigeonpea (Cajanus cajan (L.) Millspaugh), while on other plants including sorghum (Sorghum bicolor (L.)) high parasitism levels of this host are found. In this study two strategies designed to increase the parasitoid activity on pigeonpea were tested in the field: intercropping pigeonpea with sorghum and mass-releasing T. chilonis Ishii. Neither strategy led to an increase in parasitism. On pigeonpea, H. armigera oviposited >74.8% of its eggs on calyxes and pods. Parasitism levels in host eggs collected from different plant structures varied significantly with 3.6, 0.3, and 40.7% of eggs on calyxes, pods, and leaves parasitized. Earlier studies have shown that calyxes and pods possess long glandular and non-glandular trichomes, and are covered by sticky trichome exudates which inhibit parasitoid searching behaviour. Parasitism levels between 27.9 and 100% were recorded from host eggs on the intercropped sorghum. Trichogramma chilonis was the dominant parasitoid species. The mean clutch size was 2.03, but up to six parasitoids emerged per egg. Progeny sex ratio (% females) decreased with clutch size, from 63.1% at a clutch size of one to 46.0% at a clutch size of five. Sticky trap catches showed that while the parasitoid population in sorghum increased when H. armigera started ovipositing, the population within pigeonpea did not benefit from either a high parasitoid population in sorghum or a high host egg density on pigeonpea. During one of five seasons studied, however, high parasitism levels (up to 73%) were recorded on pigeonpea. During this season, H. armigera oviposited on pigeonpea plants in the vegetative growth stage and a high proportion of eggs were collected from leaves. Parasitism levels were positively correlated with the percentage of eggs collected from leaves. This study shows that the parasitization efficiency of Trichogramma spp. on pigeonpea depends mainly on the location of the host eggs. This explains why parasitism levels of H. armigera eggs on pigeonpea did not increase when intercropped with sorghum or after mass-releasing T. chilonis.