Aphis gossypii

The objective of this research was to identify colour and size of sticky trap as well as the proper time to trap winged imago of Aphis gossypii Glover. The experiment was arranged in a factorial completely randomized design (FCRD) consisted of 2 treatments and 12 replications. First treatment was size of sticky trap (2 levels) and the second treatment was colour of sticky trap (5 levels). The 5 colours of the sticky traps were yellow, orange, green, blue and red. Sizes of the sticky trap were large size (2.480 cm 2) and small size (610 cm 2). The results showed that trap colour, trap size, and their interaction significantly affected the result trapped winged imagoes of A. gossypii. Time of trapping also significantly affected the result. Yellow was the most preferred colour by the aphid A. gossypii compared to other colours. The least preferred colours were red and blue. The big sticky trap could catch more winged A. gossypii imagoes than the small trap. Evening trapping could catch more winged A. gossypii imagoes compared to that of morning trapping. ABSTRAK Penelitian ini bertujuan mengetahui warna-warna, ukuran dan waktu dalam memerangkap imago kutudaun Aphis gossypii Glover bersayap. Penelitian ini menggunakan Rancangan Acak Lengkap Faktorial (RALF) yang terdiri dari 2 ukuran dan 5 perlakuan warna masing-masing kombinasi perlakuan diulang 12 kali. Warna sticky traps yang digunakan ialah warna kuning, orange, hijau, biru dan merah. Ukuran sticky traps yang digunakan ialah ukuran besar luasnya 2.480 cm 2 dan ukuran kecil luasnya 610 cm 2. Hasil penelitian menunjukkan bahwa warna, ukuran dan variasi keduanya serta waktu pengamatan berpengaruh nyata dalam menangkap imago kutudaun A. gossypii. Warna kuning merupakan warna yang paling disukai kutudaun A. gossypii diantara warna-warna yang lain. Warna yang paling tidak disukai oleh kutudaun ialah warna merah dan biru. Sticky traps berukuran besar menangkap imago kutudaun A. gossypii bersayap lebih banyak

Abacá mosaic virus (AbaMV) is related to members of the sugarcane mosaic virus subgroup of the genus Potyvirus. The ∼2 kb 3′ terminal region of the viral genome was sequenced and, in all areas analysed, found to be most similar to Sugarcane mosaic virus (SCMV) and distinct from Johnsongrass mosaic virus (JGMV), Maize dwarf mosaic virus (MDMV) and Sorghum mosaic virus (SrMV). Cladograms of the 3′ terminal region of the Nib protein, the coat protein core and the 3′ untranslated region showed that AbaMV clustered with SCMV, which was a distinct clade and separate from JGMV, MDMV and SrMV The N-terminal region of the AbaMV coat protein had a unique amino acid repeat motif different from those previously published for other strains of SCMV The first experimental transmission of AbaMV from abacá (Musa textilis) to banana (Musa sp.), using the aphid vectors Rhopalosiphum maidis and Aphis gossypii, is reported. Polyclonal antisera for the detection of AbaMV in western blot assays and ELISA were prepared from recombinant coat protein expressed in E. coli. A reverse transcriptase PCR diagnostic assay, with microtitre plate colourimetric detection, was developed to discriminate between AbaMV and Banana bract mosaic virus, another Musa-infecting potyvirus. Sequence data, host reactions and serological relationships indicate that AbaMV should be considered a distinct strain of SCMV, and the strain designation SCMV-Ab is suggested.

— A field study was conducted at plant protection department, college of Agriculture/University of Baghdad to determine castor oil plant pestsRicinuscommunis, for the period between 2/9/2014 to 17/6/2015. Results showed that castor oil plant (Ricinuscommunis) was infested by the castor oil plant leaf minor Lirimoyzatrifolii and cotton aphidAphis gossypii.The highest population densities of the leaf minor at western side were 6.8 insect/leaf and the lowest were 0.6/leaf dated in 30/4,7/5 and17/6 , respectively.Whereas,the highest population densities at northern side were 5.6 insect /leaf recored in 9/9 while The lowest population densities of the leaf minor at northern side were 0.3 insect/leaf dated in 10/6,17/6 and 30/4 respectively. The highest population densities of the leaf minor at southern side were7.5 and the lowest were0.3insect/leaf dated in 3/6 , 2/1 respectively. At eastern side, the highest densities were 5.6 insect/leaf dated in2/9 and the lowest were 0 in 10/6 respectively. For cotton aphid, the highest population densities were for the northern side with4.2 cm2/leaf discdated in 2/9and the lowest were 0 cm2/leaf disc dated in12/4 and 30/4. Whereas they were 4.8cm2/leaf disc in 19/11 and 0cm2/leaf disc in 30/1and 30/4 for western as highest and lowest densities respectively the highest population densities for the eastern sides were 3.6 in 19/11 while the lowest population density were 0.3 in 23/1 ,30/1 , 22/2 ,23/4 and 7/5 ,the highest population densities for the southeren side were 7cm2/leaf discin 23/4 while the lowest population density were 0.2 in 9/9 respectively. The highest incidence was for the parasite Pediobiusmetalicus. While, the hymenopteran Neochrysochairsformosa, Digylphuscrassinervis and Pediobiusmetalicus were reported to parastize on castor oil leaf minor.

In an attempt to clarify the potential role of endophytic fungi in integrated pest management, the compatibility of an endophytic isolate of Lecanicillium lecanii (Zimmermann) Gams & Zare (Hyphomycetes) with nine insecticides used against Aphis gossypii Glover (Homoptera : Aphididae) was examined both in vitro over 14 days and in planta. In the laboratory, most insecticides partially or completely inhibited the germination of conidia and growth of hyphae in nutrient-rich conditions. Endosulfan completely inhibited the germination of conidia and hyphal growth. In contrast, all insecticides were compatible with L. lecanii in planta, and the fungus was readily recovered from inoculated, colonized leaves. These data support the hypothesis that endophytic L. lecanii will be unaffected by insecticides and could be integrated in the management of pests in cotton.

Aphidius colemani Viereck is among the main natural enemies used for biological control of Aphis gossypii Glover. The objective of the present study was to evaluate the development of A. colemani and the alterations caused by the parasitism in the host A. gossypii in different temperatures and to estimate the thermal requirements of the parasitoid. The experiments were carried out in controlled environmental chambers at 16, 19, 22, 25, 28 and 31 ± 1ºC, 70 ± 10% RH, and 12h photophase. Second-instar nymphs of A. gossypii were parasitized once and kept individually in glass tubes (2.5 cm x 8.5 cm), containing leaf disc of cucumber (2 cm) and 1% water/agar solution. The development time of A. colemani, from oviposition to mummies (11.9, 9.8, 7.7, 6.4 and 6.4 days) and from oviposition to adult (19.4, 16.2, 12.6, 10.5 and 10.7 days) decreased with the increase of the temperature from 16ºC to 25ºC. The rates of mummies and the emergence of the parasitoid, and its longevity also decreased with the increase of the temperature. Mummies were not produced at 31ºC. The lower temperature threshold of A. colemani was 5.94ºC and its thermal constant was 200 degrees-day. The alterations caused by the parasitoid in the A. gossypii host were minimized at 31ºC, where 98% of the host did not show symptoms of parasitism and produced nymphs. The temperature of 22ºC was optimal for the development time of A. colemani.

A lectin was purified from the leaves of Allium altaicum and corresponding gene was cloned. The lectin namely Allium altaicum agglutinin (AAA) was ~24 kDa homodimeric protein and similar to a typical garlic leaf lectin. It was synthesized as 177 amino acid residues pre-proprotein, which consisted of 28 and 43 amino acid long N and C-terminal signal peptides, respectively. The plant expressed this protein more in scapes and flowers in comparison to the bulbs and leaves. Hemagglutination activity (with rabbit erythrocytes) was 1,428 fold higher as compared to Allium sativum leaf agglutinin (ASAL) although, the insecticidal activity against cotton aphid (Aphis gossypii) was relatively low. Glycan array revealed that AAA had higher affinity towards GlcAb1-3Galb as compared to ASAL. Homology analysis showed 57–94% similarity with other Allium lectins. The mature protein was expressed in E. coli as a fusion with SUMO peptide in soluble and biologically active form. Recombinant protein retained high hemagglutination activity.

The study of intraspecific variation with respect to host plant utilization in polyphagous insects is crucial for understanding evolutionary patterns of insect-plant interactions. Aphis gossypii (Glover) is a cosmopolitan and extremely polyphagous aphid species. If host plant species or families constitute selective regimes to these aphids, genetic differentiation and host associated adaptation may occur. In this study, we describe the genetic structure of A. gossypii collected in six localities in Tunisia on different vegetable crops, on citrus trees and on Hibiscus. The aim was to determine if the aphid populations are structured in relation to the host plants and if such differentiation is consistent among localities. The genetic variability of A. gossypii samples was examined at eight microsatellite loci. We identified only 11 multilocus genotypes among 559 individuals. Significant deviations from Hardy-Weinberg equilibrium, linkage disequilibria and absence of recombinant genot...

The use of living mulches to reduce the density of silverleaf whitefly, Bemisia argentifolii Bellows and Perring, and melon aphid, Aphis gossypii Glover, and the conveyances of aphid-transmitted virus, papaya ringspot virus-watermelon strain (PRSV-W), and squash silverleaf disorder on zucchini, Cucurbita pepo L. was evaluated during 1995 and 1996 in Oahu, Hawaii. Living mulches used were buckwheat (Fagopyrum esculentum Moench)

Laboratory experiments were conducted to determine the functional and numerical responses of fourth instar larvae, adult male, and adult female ladybird beetles, Anegleis cardoni Weise (Cole-optera: Coccinellidae), to different densities of aphids, Aphis gossypii Glover (Hemiptera: Aphididae), on the bottle gourd, Lagenaria vulgaris Seringe (Cucurbitales: Cucurbitaceae). The results revealed a density dependent, Type II functional response of A. cardoni. Prey consumption increased curvilinearly with an increase in prey density for all three predatory stages. Numerical responses revealed significant increases in oviposition with increases in prey density. The food exploitation efficiency and the efficiency of conversion of ingested food decreased with increases in prey density. The attack rate was highest for adult females, followed by fourth instar larvae and adult males. Prey consumption was highest and handling time lowest in fourth instar larvae, followed by adult females and males. Therefore, fourth instar larvae of A. cardoni may be considered the most efficient predatory stage in aphid management strategies.

Controlled release (CR) formulations of azadirachtin-A, a bioactive constituent derived from the seed of Azadirachta indica A. Juss (Meliaceae), have been prepared using commercially available polyvinyl chloride, polyethylene glycol (PEG) and laboratory synthesized poly ethylene glycol–based amphiphilic copolymers. Copolymers of polyethylene glycol and various dimethyl esters, which self assemble into nano micellar aggregates in aqueous media, have been synthesized. The kinetics of azadirachtin-A, release in water from the different formulations was studied. Release from the commercial polyethylene glycol (PEG) formulation was faster than the other CR formulations. The rate of release of encapsulated azadirachtin-A from nano micellar aggregates is reduced by increasing the molecular weight of PEG. The diffusion exponent (n value) of azadirachtin-A, in water ranged from 0.47 to 1.18 in the tested formulations. The release was diffusion controlled with a half release time (t1/2) of 3.05 to 42.80 days in water from different matrices. The results suggest that depending upon the polymer matrix used, the application rate of azadirachtin-A can be optimized to achieve insect control at the desired level and period.

Summary The seasonal flight pattern of aphid population and aphid infestation of tobacco plots were studied in sites of Southern (Mercato S. Severino and Scafati, Salerno province), Central (Lanciano, Chieti province) and Northern (Bovolone, Verona province) Italy in the year 2000, with the support of the E.U. Tobacco Research Fund and the Italian Ministry of Agriculture (Tob-Res-Info 96/T/18 project). Flight monitoring was carried out by means of Moericke yellow traps, while aphid infestation was assessed on a 0-5 point scale by observations on untreated tobacco plots. A total of 9,154 alatae were trapped and 66 species determined. At the Scafati station about 40% of the whole captures were collected, followed by Mercato S. Severino (31%), Bovolone (21%) and Lanciano (9%). The identified species were 55 at Scafati, 39 at Mercato S. Severino, 38 at Bovolone and 23 at Lanciano. Aphis was the most conspicuous group, with over 60% of total captures. Aphis gossypii Glover and Aphis faba...

The intrinsic rate of increase of a parasitoid related to its hosts play an important role in biological control programs. In this work, fertility of the parasitoid Aphidius colemani Viereck was evaluated on Aphis gossypii Glover by means of a fertility life table. To determine the immature mortality, the development time and the sex ratio, 12 mated females of A. colemani (24h old), and 240 nymphs of A. gossypii (3 days old) were used. To evaluate fertility 15 mated females (24h old) were used. For each parasitoid female, 300 nymphs were offered in the 1st day, 250 nymphs in the 2nd day, 200 nymphs in the 3rd day, 150 nymphs in the 4th day, 100 nymphs in the 5th day and 50 nymphs in the other days. Immature mortality of A. colemani was 22.1%, development time of males and females were 12.0 and 11.8 days, respectively, and sex ratio was 0.6. The females of A. colemani laid 420 eggs and had longevity of 5.9 days. The net reproduction rate (Ro) was 194.81 females and the intrinsic rate of increase (rm) was 0.384 females/females/day. The finite rate of increase (l) was 1.48 females/day, the mean length of a generation (T) was 13.74 days and the time to duplication the population (TD) was 12.60 days. The parasitoid A. colemani had a great potential of population growth on A. gossypii as a host and could be an effective biological control agent of this aphid.

... 1 ; Suhail, Anjum 1 ; Gogi, M. Dildar 1 ; Yaseen, M. 2 ; Asghar, M. 1 ; Tayyib, M. 1 ; Karar, Haider 1 ; Hafeez, Faisal 1 ; Ullah, Unsar Naeem 1. Source: International Journal of Pest Management, Volume 55, Number 1, January 2009 , pp. 1-10(10). Publisher: Taylor and Francis Ltd. ...