Showing 9 results for Askari Seyahooei
Volume 6, Issue 2 (6-2017)
Abstract
Bactrocera zonata (Saunders) (Diptera: Tephritidae), an extremely aggressive species infesting some of the main commercial fruit and vegetables, has been subjected to a diverse array of control approaches. In the current study, performance of various Methyl Eugenol (ME) dispensers in combination with an organophosphate insecticide, Malathion, were evaluated against B. zonata in two consecutive years (2006-2007). Treatments efficacy was studied in various months using the criterion of trapped B. zonata flies. ANOVA revealed a significant difference among various application methods in both fruit infestation rate and capture of B. zonata flies. So that impregnation of chipboard block in ME caused the lowest B. zonata infestation and the highest B. zonata capturing values in both years. Population fluctuation study revealed a major peak for B. zonata in September i.e., mango ripening time. According to our results, it could be suggested that chipboard dispenser is the best application method as attractant in bait trap which exhibits more potent and longer lasting activity.
Volume 8, Issue 1 (1-2019)
Abstract
Health and environmental side effects of chemical insecticides and development of resistant population of Helicoverpa armigera Hubner (Lepidoptera: Noctuidae) to pesticides have resulted in increasing demands for non-chemical control approaches against this pest. In this research, the efficacy of two biological control agents were studied under field condition. Treatments consisted of releasing Habrobracon hebetor (Say) (Hymenoptera: Braconidae), Trichogramma evanescence Westwood (Hymenoptera: Trichogrammatidae) and combination of H. hebetor + T. evanescence (HABROBRACON-TRICO). The results revealed significant differences in the number of infested tomato fruits among treatments and harvesting times. The infested fruits was the lowest (2.68 ± 0.14%) in plots treated by HABROBRACON-TRICO. Moreover, the highest (3.36 ± 0.50%) and the lowest (2.88 ± 0.22%) damaged fruits was recorded in the second and fourth harvesting times, respectively. There was significant interaction between harvesting times and treatments. Regarding the tomato yield in treatments, findings revealed significant difference among treatments in both main harvesting times. However, there was no significant differences in total yield in treatments. It could be concluded that biological control agents can be used as a promising alternative for synthetic insecticides in control of H. armigera in tomato farms without significant crop losses.
Volume 9, Issue 2 (2-2020)
Abstract
Despite successful lime witches'-broom (LWB) phytoplasma transmission by Hishimonus phycitis to the lime trees and Bakraee seedlings, there is no published document regarding LWB transmission by H. phycitis to lime seedlings. To study the possibility of vector-based transmission to lime seedlings, the feral leafhoppers were collected in LWB-infected lime orchards and caged on one-year old Mexican lime seedlings. Six months after inoculation, 50% of inoculated seedlings showed typical symptoms of LWB and were strongly positive in PCR assays. To our knowledge, this is the first report of transmission of Ca. P. aurantifolia to Mexican lime seedlings by H. phycitis under greenhouse condition.
Volume 10, Issue 4 (11-2021)
Abstract
Habrobracon hebetor Say (Hymenoptera: Braconidae) is an ectoparasitoid wasp in the family Braconidae and is widely used in biological pest control. Little information is available on the genetic diversity of geographically isolated populations of H. hebetor. In the present study, we assess the genetic structure and diversity of geographically distinct populations of H. hebetor collected from different regions of Iran. To this end, 19 populations of H. hebetor (Dehloran, Hamadan, Minab, Rudan, Ahvaz, Sari, Semnan, Bandar Lengeh, Haji Abbad, Jiroft, Shiraz, Sarpol-e Zahab, Gorgan, Isfahan, Urmia, Kahurestan, Taziyan, Isin, and Sarkhun) were collected from natural niches. For each population, we sequenced a ~660 base pair fragment of Cytochrome Oxidase subunit I (COI) successfully. Analysis of molecular variance revealed sharp differentiation among H. hebetor populations. Populations from Ahvaz, Dehloran, Jiroft and Minab were the most genetically diverged. A Mantel test showed significant positive correlation between genetic and geographic distances (r = 0.47, P < 0.001). The phylogenetic analysis clustered the populations into two major groups (A and B) (100); the major part was assigned to group A. Group B mainly included the populations from southern Iran. Based on these results, we conclude that H. hebetor in Iran is comprised of many diverse populations. These may be successfully applied in innundative release programs.
Volume 10, Issue 4 (11-2021)
Abstract
Tomato leafminer moth Tuta absoluta (Meyrick) is an important pest of the tomato plant. Light traps can play an influential role in reducing the pest population. Different light colors, three trap sizes, and three installation heights were evaluated under laboratory conditions. The light colors were white, yellow, green, red, blue, and blacklight blue (BLB). The traps, transparent containers of three sizes were 8.5, 10.5, and 14.5 cm in diameter and 15, 19, and 26 cm in height, respectively. The trap installation heights were 50, 75, and 100 cm above the plants’ canopy. The BLB color proved significantly more attractive to T. absoluta, followed by yellow and white colors. The light traps captured more males than females and more mated females than virgin ones. Both of the larger traps (10.5 cm d × 19 cm h and 14.5 cm d × 26 cm h), and higher installed ones (100 cm and 75 cm above the plants), captured a significantly higher number of moths compared to the smaller trap size and lower installation height. Accordingly, for mass trapping of moths, light traps with BLB source of light, with 10.5 cm in diameters and 19 cm in height, and installation at 75 cm above the canopy is recommended in greenhouses.
Volume 17, Issue 109 (March 2021)
Abstract
Green mold rot disease caused by Penicillium digitatum is the most economically important postharvest disease of lime fruit in all production areas. In this research, effects of essential oils (Cinnamomun verum, Eugenia caryophyllata, Thymus vulgaris, Zataria multiflora) for controlling green mold in Mexican lime (Citrus aurantifolia cv. Mexican lime) fruit were studied. Mexican limes were inoculated by Penicillium digitatum suspension and were immersed with the essential oils at three levels 0 (as control), 0.1 and 0.2% (v/v). Then, fruits were kept at 8±1oC and 90-95% relative humidity for 21 days. The results showed that the essential oils significantly affected fruit decay, weight loss, L*, a*, b*, total phenolic content and total antioxidant activity. After 21 days of storage, total phenolic content and total antioxidant activity of treated fruit with essential oils were higher compared with the control. In addition, essential oils were effective in decay and water loss control, and decreasing L* and b* compared with the control. The garden thyme essential oil at 0.2% decreased postharvest decay seven times lower than control but increased total phenolic compounds and antioxidant activity compared to the control 21 days after storage. Therefore, garden thyme essential oil has a strong effect on controlling green mold and maintaining quality of Mexican lime fruit.
Volume 19, Issue 123 (May 2022)
Abstract
Abstract
The use of natural ingredients such as edible coatings is considered as an environmental friendly way to control post-harvest fruit rot as well as delay fruit senescence. The aim of this study was to investigate the effects of edible coatings for controlling fruit rot caused by Penicillium digitatum and some qualitative characteristics of Mexican lime during storage. Mexican limes were inoculated with fungi suspension and were immersed in carboxymethyl cellulose (CMC), hydroxylpropyl methylcellulose (HPMC) and sodium alginate (ALG) coatings at four concentrations of 0 (control), 0.5, 1 and 1.5%. Then, Mexican lime fruit were stored at temperature of 8 ° C and relative humidity of 90-95% for 21 days. The results showed that edible coatings showed significant effects on fruit rot, weight loss, percentage of soluble solids, titratable acid, L *, a *, phenolic content and total antioxidant activity. Among the edible coatings, CMC at 1.5% reduced the fruit rot caused by green mold (77%) and reduced the weight loss (80%), TSS (5%) and increased the titratable acidity (33%) and total antioxidant activity (10%) compared to the control after 21 days of storage. Therefore, the use of edible coatings, especially 1.5% CMC, can maintain qualitative characteristics of Mexican lime and reduce the rot. Therefore, it can be used as an environmental friendly method to maintain fruit quality and reduce post-harvest waste.
Volume 20, Issue 5 (7-2018)
Abstract
Witches' broom disease of lime caused by 'Candidatus Phytoplasma aurantifolia' is considered as one of the most destructive disease of Mexican lime in southern Iran, Oman, and the United Arab Emirates. The causative phytoplasma is vectored by a leafhopper, Hishimonus phycitis (Distant, 1908). Six ISSR markers and mitochondorial Cytochrome c Oxidase I (COI) gene were used to unveil genetic variation of the leafhopper populations from thirteen different regions of Iran. Analysis of ISSR markers revealed that Forg (Fars) and Qale'e Qazi (Hormozgan) significantly diverged from the other populations. However, the COI sequences were highly conserved among all populations and resided all the populations in a single clade. Mantel test exhibited no correlation between genetic and geographical distances. Our results demonstrated genetic differentiations among the H. phycitis populations, which might have been induced by ecological or geographical isolation and may affect the vectoring capability of this insect.
Volume 22, Issue 3 (4-2020)
Abstract
Augmentative release of native natural enemies is a prominent strategy for suppression of crop pests. Intrinsic differences among populations of natural enemies may affect their efficiency in pest management programs. We characterized life history traits of 13 climatically and geographically isolated populations of Habrobracon hebetor Say (Hymenoptera: Braconidae) from different regions of Iran to assess their suitability for biological control of noctuid moths. All experiments were performed at 25±1°C, 65±5 RH and 16:8 (L:D) hours photoperiod regime. Ephestia kuehniella (Zeller) (Lepidoptera: Pyralidae) was used as a laboratory host. Our results revealed significant variation in female longevity, paralysis and parasitism rate, sex ratio, reproductive rate and host allocation among different H. hebetor populations tested. The highest number of offspring (124.2) and parasitized larvae (160.1) were observed in Bandar Lengeh and the lowest ones was observed in Urmia and Jiroft, respectively (3.4 and 9.3 for Urmia and 3.1 and 10.1 for Jiroft). Also, the wasps of Bandar Lengeh paralyzed more than 95% of the introduced host larvae. The longest female longevity and male production (21.3 days and 80.1, respectively) were in Bandar Abbas and Bandar Lengeh (21.3 days and 80, respectively), while the lowest ones were in Dehloran (12.9 days and 40.2, respectively). Gorgan population deployed the highest number of Ephestia kuehniella larvae in foraging behavior test. These results show considerable variation in the life history traits of various populations of H. hebetor, which may affect performance of these populations under field condition.