Effects of Acetamiprid at Low and Median Lethal Concentrations on the Development and Reproduction of the Soybean Aphid Aphis glycines

The soybean aphid Aphis glycines Matsumura (Hemiptera: Aphididae) is a major pest of soybean and poses a serious threat to soybean production. Studies on the effect of acetamiprid on the life table parameters of A. glycines, provide important information for the effective management of this pest. We found that exposure to acetamiprid at LC50 significantly extended the mean generation time, adult pre-reproductive period, and total pre-reproduction period compared with the control, whereas exposure to acetamiprid at LC30 significantly shortened these periods. Exposure to acetamiprid at both LC30 and LC50 significantly decreased the fecundity of the female adult, net reproductive rate, intrinsic rate of increase, and finite rate of increase compared with the control. The probability of attaining the adult stage was 0.51, 0.38, and 0.86 for a newly born nymph from the LC30 acetamiprid treatment group, LC50 acetamiprid treatment group, and control group, respectively. Acetamiprid at both LC50 and LC30 exerted stress effects on A. glycines, with the LC50 treatment significantly decreased the growth rate compared with the LC30 treatment. The present study provides reference data that could facilitate the exploration of the effects of acetamiprid on A. glycines in the field.

Effects of imidacloprid and thiamethoxam on the development and reproduction of the soybean aphid Aphis glycines

The soybean aphid Aphis glycines Matsumura (Hemiptera: Aphididae) is a primary pest of soybeans and poses a serious threat to soybean production. Our studies were conducted to understand the effects of different concentrations of insecticides (imidacloprid and thiamethoxam) on A. glycines and provided critical information for its effective management. Here, we found that the mean generation time and adult and total pre-nymphiposition periods of the LC50 imidacloprid- and thiamethoxam-treatment groups were significantly longer than those of the control group, although the adult pre-nymphiposition period in LC30 imidacloprid and thiamethoxam treatment groups was significantly shorter than that of the control group. Additionally, the mean fecundity per female adult, net reproductive rate, intrinsic rate of increase, and finite rate of increase of the LC30 imidacloprid-treatment group were significantly lower than those of the control group and higher than those of the LC50 imidacloprid-treatment group (P < 0.05). Moreover, both insecticides exerted stress effects on A. glycines, and specimens treated with the two insecticides at the LC50 showed a significant decrease in their growth rates relative to those treated with the insecticides at LC30. These results provide a reference for exploring the effects of imidacloprid and thiamethoxam on A. glycines population dynamics in the field and offer insight to agricultural producers on the potential of low-lethal concentrations of insecticides to stimulate insect reproduction during insecticide application.

Erratum to “Biology and the Statistic Demographic of Aphis glycines Matsumura (Hemiptera: Aphididae) on the Soybean with Plant Growth Promoting Rhizobacteria (PGPR) Treatment” [Jurnal Perlindungan Tanaman Indonesia, 24(1), 54‒60]

This is a correction to: Biology and the Statistic Demographic of Aphis glycines Matsumura (Hemiptera: Aphididae) on the Soybean with Plant Growth Promoting Rhizobacteria (PGPR) Treatment. Jurnal Perlindungan Tanaman Indonesia, 24(1), 54‒60. https://doi.org/10.22146/jpti.49846 In Author’s affiliation, typed as:Hermanu Triwidodo1)*, Anggun Agustini1), & Listihani1)1)Department of Plant Protection, Faculty of Agriculture, IPB UniversityJln. Kamper, Kampus IPB Dramaga, Bogor, West Java 16680 IndonesiaTherefore, the Author’s affiliation was corrected to:Hermanu Triwidodo1)*, Anggun Agustini1), & Listihani2)1)Department of Plant Protection, Faculty of Agriculture, IPB UniversityJln. Kamper, Kampus IPB Dramaga, Bogor, West Java 16680 Indonesia2)Faculty of Agriculture and Business, University of Mahasaraswati DenpasarJln. Kamboja No.11 A, Dangin Puri Kangin, Denpasar Utara, Bali 80233 Indonesia The editorial staff apologizes for the inconvenience. The online version of the corrected manuscript has been published in the open journal system of the Jurnal Perlindungan Tanaman Indonesia.

A Detailed Spatial Expression Analysis of Wing Phenotypes Reveals Novel Patterns of Odorant Binding Proteins in the Soybean Aphid, Aphis glycines

The wide range of insect niches has led to a rapid expansion of chemosensory gene families as well as their relatively independent evolution and a high variation. Previous studies have revealed some functions for odorant-binding proteins (OBPs) in processes beyond olfaction, such as gustation and reproduction. In this study, a comparative transcriptomic analysis strategy was applied for the soybean aphid, Aphis glycines, focusing on various functional tissues and organs of winged aphids, including the antenna, head, leg, wing, thorax, cauda, and cornicle. Detailed spatial OBP expression patterns in winged and wingless parthenogenetic aphids were detected by RT-qPCR. Twelve OBPs were identified, and three new OBPs in A. glycines are first reported. All OBPs showed comparatively higher expression in sensory organs and tissues, such as the antenna, head, or leg. Additionally, we found some novel expression patterns for aphid OBPs (Beckendorf et al., 2008). Five OBPs exhibited high-expression levels in the cauda and four in the cornicle (Biasio et al., 2015). Three genes (OBP2/3/15) were highly expressed in the wing (Calvello et al., 2003). Two (OBP3/15) were significantly more highly expressed in the wingless thorax than in the winged thorax with the wings removed, and these transcripts were significantly enriched in the removed wings. More details regarding OBP spatial expression were revealed under our strategy. These findings supported the existence of carrier transport functions other than for foreign chemicals and therefore broader ligand ranges of aphid OBPs. It is important for understanding how insect OBPs function in chemical perception as well as their other potential physiological functions.

BIOLOGI DAN STATISTIK DEMOGRAFI Aphis glycines PADA TANAMAN KEDELAI

Penelitian ini bertujuan untuk mempelajari dan mendapatkan informasi mengenai aspek biologi dan statistik demografi Aphis glycines pada tanaman kedelai. Penelitian dilaksanakan di Laboratorium Hama dan Rumah Kawat, Jurusan Hama dan Penyakit Tumbuhan, Fakultas Pertanian, Universitas Brawijaya, Malang pada bulan November 2019 sampai Maret 2020. Pengamatan biologi meliputi siklus hidup, lama hidup, dan keperidian A. glycines, digunakan dalam perhitungan data demografi. Parameter demografi meliputi laju reproduksi kotor (GRR), laju reproduksi bersih (R0), laju pertambahan instrinsik (rm), dan masa generasi (T). Hasil penelitian menunjukkan bahwa A. glycines mempunyai tahap perkembangan meliputi fase nimfa instar I sampai instar IV dengan rataan perkembangan berturut-turut berlangsung selama 1,000; 1,118; 1,068; 1,091 hari. Rataan siklus hidup A. glycines terjadi selama 4,352 hari dengan keperidian 50,363 individu/imago betina. Sedangkan rataan lama hidup A. glycines yaitu 12,843 hari. Nilai statistik demografi A. glycines pada tanaman kedelai diperoleh antara lain nilai GRR sebanyak 50,373 individu/generasi, nilai R0 sebanyak 35,681 individu/ induk/generasi, nilai rm sebanyak 0,285 individu/induk/hari, dan nilai T yaitu 12,557 hari.

Variation in Soybean Aphid (Hemiptera: Aphididae) Biotypes Within Fields

Soybean aphid (Aphis glycines Matsumura (Hemiptera: Aphididae)) has been a major pest of soybean in North America since its detection in this continent in 2000 and subsequent spread. Although several aphid resistance genes have been identified, at least four soybean aphid biotypes have been discovered, with three of them being virulent on soybean cultivars with certain soybean aphid resistance genes. These biotypes are known to vary across years and locations, but information on their variation within single fields is limited. An investigation was conducted to study the variation of soybean aphid biotypes within single townships and fields in Minnesota. Screening of 28 soybean aphid isolates collected from seven soybean fields (six soybean fields in Cairo and Wellington Townships of Renville County, MN and one field in Wilmar Township of Kandiyohi County, MN) revealed the existence of multiple known biotypes of soybean aphid within single fields of soybean. We found up to three biotypes of soybean aphid in a single field. Two biotypes were found in five fields while only one field had only a single biotype. Three isolates presented reactions on a panel of resistant and susceptible indicator lines that were different from known biotypes. These results highlight the importance of characterizing soybean aphid biotypes in small geographical areas and utilizing generated knowledge to develop soybean cultivars pyramided with multiple resistance genes. The outcome will be decreased use of insecticides, thereby improving economic and environmental sustainability of soybean production.

Effects of imidacloprid and thiamethoxam at LC30 and LC50 on the life table of soybean aphid Aphis glycines (Hemiptera: Aphididae)

The soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), is a main pests of soybean that poses a serious threat to its production. Studies were conducted to understand effects of the different concentrations of the insecticides (imidacloprid and thiamethoxam) on the life table of A. glycines to provide vital information for its effective management. We found that the mean generation time, adult and total pre-oviposition periods in A. glycines specimens exposed to LC50 imidacloprid and thiamethoxam were significantly longer than those in the control group. However, when exposed to LC30 imidacloprid and thiamethoxam, the adult pre-ovipositional period was significantly shorter than that in the control group. The mean fecundity per female adult, net reproductive rate, intrinsic rate of increase, and finite rate of increase were significantly decreased in individuals exposed to LC30 and LC50 concentrations of imidacloprid and thiamethoxam, respectively (P < 0.05). Both insecticides produce stress effects on A. glycines, and specimens treated with LC50 concentrations of the two insecticides exhibited a significant decrease in their growth rates than those treated with LC30 concentrations. This study provides data that can be used as a reference to predict the effect of imidacloprid and thiamethoxam on the population dynamics in the field, and agricultural producers could attach importance to prevent stimulation the reproduction made by low-lethal concentrations during actually applying pesticides.