The response of two Bactrocera species (Diptera: Tephritidae) to fruit volatiles

Waqar Jaleel,Yurong He,Lihua Lü 한국응용곤충학회 2019 Journal of Asia-Pacific Entomology Vol.22 No.3

Bactrocera dorsalis and B. correcta are serious pests of agricultural fruit crops. Both species are widely distributed in tropical and subtropical countries, especially in Asia. For integrated management of both Bactrocera species, understanding their olfactory behavior is vital for designing reliable control strategies. In this study, the response of female B. dorsalis and B. correcta adults to three main volatile components of fruits was evaluated using the Ytube olfactometer. Our results showed that at higher concentrations all volatile components, except α-humulene and its combination with β-caryophyllene, attracted significantly more B. dorsalis than the untreated arm. For B. correcta, all the volatile components attracted significantly more females in the treated arm than the untreated arm. However, at 5% and 1% concentration, all the volatile components had similar attraction for B. dorsalis females. In the case of female B. correcta, the percentage of attraction was similar for all the individual volatile chemicals and their respective mixtures at 10% concentration. While, at 5% and 1% concentrations, the percentage of attraction was significantly higher for a mixture of β-caryophyllene and α-humulene than that of individual volatile components and all possible mixture of two and three volatile components. Based on the olfactometer results, this study concluded that 3-carene and the mixture of β-caryophyllene and α-humulene are strong attractants for female flies of B. dorsalis and B. correcta, respectively. This study might be helpful for the bait application against the female adults of B. dorsalis and B. correcta in farms and orchards.

Effect of Laser Power on Anisotropic Microstructure and Mechanical Behavior of Biomedical Ti-35Nb-15Zr (at%) Alloy Fabricated by Laser Powder Bed Fusion

Jun Zhou,Yurong Wang,Geng Zhi,Lugui He 대한금속·재료학회 2024 METALS AND MATERIALS International Vol.30 No.1

In this study, the anisotropy of Ti-35Nb-15Zr (at%) fabricated in situ using laser powder bed fusion (LPBF) was investigated for the first time. The effects of varying laser powers on the anisotropic microstructure and mechanical properties were investigated. The equiaxed grains growing in the horizontal section were finer than the β-columnar grains growing in the vertical section, and the grain size increased from 8.8 to 10.47 μm as the laser power increased. The difference in microstructure generally resulted in higher nanohardness in the horizontal Sect. (7.12, 6.70, and 6.49 GPa at 250, 275, and 300 W laser power, respectively) than in the vertical Sect. (5.41, 5.56, and 5.38 GPa at 250, 275, and 300 W laser power, respectively). The yield strength (1223.48 ± 27.67 MPa) and ductility (6.77 ± 0.48%) of the samples were both higher in the horizontal direction. The Young’s modulus of the samples in the horizontal direction, which reached as low as 72.82 ± 0.77 GPa, were lower than those in the vertical section, with a minimum of 77.59 ± 1.89 GPa. With increasing laser power, the yield strength in the horizontal direction, Young’s modulus, and yield strength in the vertical direction increased, whereas the yield strength in the vertical direction decreased. In particular, the Ti-35Nb-15Zr alloy exhibited better cellular activity than cast Ti6Al4V. All samples formed dense, bone-like apatite layers on the surface in different directions, demonstrating the great potential of the LPBF Ti-35Nb-15Zr alloy as an implant.

Feeding behavior of the notorious invasive Mealybug, Phenacoccus solenopsis to exotic weeds using EPG

Wang Qianjin,Qi Guojun,He Yurong,Lyu Lihua 한국응용곤충학회 2023 Journal of Asia-Pacific Entomology Vol.26 No.2

The cotton mealybug, Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) is notorious for causing severe economic losses to a wide range of crop species. It is noteworthy that this mealybug performed different host preference and fitness within their host range. In order to determine the preference of P. solenopsis between economic plants and weeds, the feeding behavior of cotton mealybug on three widespread exotic weeds belong to Asteraceae family (Bidens pilosa L., Wedelia trilobata and Ambrosia artemisiifolia.) were determined and compared with cotton Gossypium hirsutum L. using electrical penetration graph (EPG). Compared with G. hirsutum, cotton mealybug took the shortest time for trying/detecting on leaf surface and spend the longest duration times for ingestion from phloem bundle tissues feeding on A. artemisiifolia. Results showed that A. artemisiifolia was the most adaptable host for cotton mealybug, B. pilosa and W. trilobata were less suitable ones, implying these plants vulnerable to damage by this mealybug. This consequence gave more evidence for the feeding harm of P. solenopsis and might provide a scientific basis for explain if exotic weeds play an important role in the regional dispersal, and exist as transfer host for pest divert to farmland during uncultivated season.

Walking patterns of Trichogramma chilonis and Trichogrammatoidea bactrae upon vegetable leaf surfaces

Desen WANG,Xiaofang HE,Chengyin ZHAO,Yurong He,Lihua LU,Yongli LUO,Hualong QIU 한국곤충학회 2020 Entomological Research Vol.50 No.1

Trichogramma chilonis Ishii (Hymenoptera: Trichogrammatidae) and Trichogrammatoidea bactrae Nagaraja (Hymenoptera: Trichogrammatidae) are egg parasitoids of the diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae). We observed and recorded the walking patterns of T. chilonis and T. bactrae females on leaves of Raphanus sativus L., Brassica juncea (L.) Czern. et Coss., Brassica campestris L. ssp. chinensis var. utilis Tsen et Lee, and Brassica oleracea L. Our analysis indicated that Trichogramma females spent more time and moved more slowly on R. sativus leaf surface, compared with the other vegetable leaf surfaces. In addition, Trichogramma females were more likely to walk in straight line on B. oleracea leaf surfaces than R. sativus, B. juncea, and B. campestris leaf surface. Compared to T. bactrae females, T. chilonis females spent significantly less time on the leaf surface, and the walking path of T. chilonis was less affected by leaf surface characters (e.g., trichomes, wrinkle, and waxes). During the period of residence on the leaf surface, parasitoid females spent more than 87.8% of their time moving. This study demonstrates that vegetable leaf surface can influence Trichogramma’s walking pattern while they are foraging for hosts.

Effects of soil-treatment with fungal biopesticides on pupation behaviors, emergence success and fitness of tea geometrid, Ectropis grisescens (Lepidoptera: Geometridae)

TaoMa,Huifang Wang,Shiping Liang,Qiang Xiao,Panrong Cao,Xuan Chen,Ying Niu,Yurong He,Zhaohui Sun,XiujunWen,Cai Wang 한국응용곤충학회 2019 Journal of Asia-Pacific Entomology Vol.22 No.1

Ectropisgrisescens Warren (Lepidoptera: Geometridae) is one of the most severe defoliating pests of tea plants. Synthetic pesticides have been widely applied to control this pest in tea plantations, but pesticide residues may decrease the quality and safety of tea products. In the present study, we hypothesized that soil treatment with the two commercial biopesticides (Shuiguxin ® ) based on Metarhizium anisopliae (Metchnikoff) Sorokin and Beauveria bassiana (Balsamo) could reduce the survivorship and fitness of E. grisescens. Wandering larvae of E. grisescens were allowed to pupate in soil treated with each biopesticide, and the concentrations of M. anisopliae (Shuiguxin ® ) and B. bassiana (Shuiguxin ® ) that produced the 50% mortality values (LC 50 ) were 2.9 × 10 6 and 1.6 × 10 7 conidia/g soil, respectively. Artificial burying the pupae using soil treated with M. anisopliae (Shuiguxin ® ) and B. bassiana (Shuiguxin ® ) (1 × 10 8 or 1 × 10 9 conidia/g soil for both biopesticides) also significantly reduced emergence success of E. grisescens. In addition, choice tests showed that soil treated with the high concentration of M. anisopliae (Shuiguxin ® ) or B. bassiana (Shuiguxin ® ) had repellent effects on pupating E. grisescens. However, sublethal concentrations (LC 25 and LC 50 ) of both biopesticides did not significantly affect fecundity, fertility and longevity of post-emerged adults. Our study showed that soil treatment with the two commercial biopesticides caused direct mortality of pupating E. grisescens, but may not effectively suppress E. grisescens populations at sublethal concentrations. The realistic application of the fungal dosage in fields should be determined in future studies

Effects of three different cultivars of cruciferous plants on the age‐stage, two‐sex life table traits of Plutella xylostella (L.) (Lepidoptera: Plutellidae)

Waqar Jaleel,Shafqat SAEED,Qamar Saeed,Muhammad Nadir NAQQASH,Muhammad Umair SIAL,Qurat Ul AINE,Lei YANYUAN,Zhao RUI,Yurong HE,Lihua LU 한국곤충학회 2019 Entomological Research Vol.49 No.4

Plutella xylostella is an important pest of cruciferous crops worldwide. However, information regarding the age‐stage, two‐sex life parameters of P. xylostella, which is vital for designing more effective control methods, is currently lacking. The present study reports age‐stage, two‐sex life table parameters for P. xylostella on napa cabbage (Brassica oleracea var. napa), white cabbage (B. oleracea var. capitata), and cauliflower (B. oleracea var. botrytis) under laboratory conditions at 25 ± 2°C, 50–60% relative humidity, and a 16‐h light : 8‐h dark photoperiod. The time for development from an egg to a male or female adult P. xylostella on white cabbage (mean [± SE] 41.15 ± 0.54 and 39.50 ± 0.54 days, respectively) was significantly longer than that on cauliflower and napa cabbage. Furthermore, P. xylostella fecundity on cauliflower (261.90 ± 4.53 eggs female) was significantly highest than on napa cabbage and white cabbage. Intrinsic rate of increase (r) and finite rate of increase (λ) were highest on cauliflower 0.182 day−1 and 1.199 day−1 respectively as comparison to napa cabbage and white cabbage. The highest gross reproductive rate (GRR) and net reproductive rates (R0) of P. xylostella 65.87 and 52.58 respectively on cauliflower then those of other hosts. The findings of the present study indicate that cauliflower is the most suitable cultivar (host) for the development of P. xylostella. Based on these findings, crops like cauliflower can be used as trap crops when napa cabbage and white cabbage are the main crops.