Effects of Insecticides on Blooming Grain Sorghum on Sorghum Midge and Sugarcane Aphid Control, 2014

The sugarcane aphid, Melanaphis sacchari (Zehntner) (Hemiptera: Aphididae) (SCA), has become a major pest of grain sorghum since its appearance in the USA. Several grain sorghum parental lines are moderately resistant to the SCA. However, the molecular and genetic mechanisms underlying this resistance are poorly understood, which has constrained breeding for improved resistance. RNA-Seq was used to conduct transcriptomics analysis on a moderately resistant genotype (TAM428) and a susceptible genotype (Tx2737) to elucidate the molecular mechanisms underlying resistance. Differential expression analysis revealed differences in transcriptomic profile between the two genotypes at multiple time points after infestation by SCA. Six gene clusters had differential expression during SCA infestation. Gene ontology enrichment and cluster analysis of genes differentially expressed after SCA infestation revealed consistent upregulation of genes controlling protein and lipid binding, cellular catabolic processes, transcription initiation, and autophagy in the resistant genotype. Genes regulating responses to external stimuli and stress, cell communication, and transferase activities, were all upregulated in later stages of infestation. On the other hand, expression of genes controlling cell cycle and nuclear division were reduced after SCA infestation in the resistant genotype. These results indicate that different classes of genes, including stress response genes and transcription factors, are responsible for countering the physiological effects of SCA infestation in resistant sorghum plants.

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Greenhouse Evaluation of Insecticides for Control of Yellow Sugarcane Aphid and Greenbug on Sorghum Seedlings, 1994

Arthropod Management Tests ◽

10.1093/amt/20.1.230 ◽

1995 ◽

Vol 20 (1) ◽

pp. 230-230

Author(s):

R. M. Anderson ◽

G. L. Teetes

Keyword(s):

Grain Sorghum ◽

Hollow Cone ◽

Soil Mixture ◽

Insecticide Application ◽

Sugarcane Aphid ◽

Greenhouse Evaluation ◽

Seedling Plant ◽

Plant Emergence ◽

Spray Volume ◽

Pre Treatment

Abstract Foliar treatments of 2 organophosphates and imidachloprid (Confidor) were evaluated for yellow sugarcane aphid (YSA) and greenbug (GB) control in a research greenhouse at Texas A&M University. Hybrid grain sorghum seedlings (ATx399 × RTx430) were grown in 110-mm germination pots containing a prepared soil mixture composed of peat, vermiculite, and periite in a 2:1:1 ratio, respectively. Four days after plant emergence and 3 d prior to insecticide applications, each seedling plant was infested with 10-20 YSA or GB. There were 5 singleseedling replications for each treatment. Insecticides were applied by using a CO2-pressurized backpack sprayer, through TX-3 hollow-cone nozzles at 35 psi, producing a finished spray volume of 5.6 gpa. Pre-treatment counts of YSA and GB were made the day of insecticide application; post-treatment counts of aphids were made 1, 2, and 3 DAT. Percent control was calculated by using Abbott’s (1925) formula. Data were statistically analyzed by using ANOVA and LSD.

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Evaluation of Insecticides for Control of the Sugarcane Aphid in Grain Sorghum, 2014: Table 1

Arthropod Management Tests ◽

10.1093/amt/tsv130 ◽

2015 ◽

Vol 40 (1) ◽

pp. F5 ◽

Cited By ~ 2

Author(s):

J. M. Beuzelin ◽

D. M. May

Keyword(s):

Grain Sorghum ◽

Sugarcane Aphid

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Differences in Microbiota Between Two Multilocus Lineages of the Sugarcane Aphid (Melanaphis sacchari) in the Continental United States

Annals of the Entomological Society of America ◽

10.1093/aesa/saaa003 ◽

2020 ◽

Vol 113 (4) ◽

pp. 257-265 ◽

Cited By ~ 3

Author(s):

Jocelyn R Holt ◽

Alex Styer ◽

Jennifer A White ◽

J Scott Armstrong ◽

Samuel Nibouche ◽

...

Keyword(s):

United States ◽

Microbial Community Composition ◽

Pcr Primers ◽

Grain Sorghum ◽

Aphid Species ◽

Invasive Pest ◽

Melanaphis Sacchari ◽

Sugarcane Aphid ◽

Bacterial Microbiota ◽

Host Associated Differentiation

Abstract The sugarcane aphid (SCA), Melanaphis Sacchari (Zehntner) (Hemiptera: Aphididae), has been considered an invasive pest of sugarcane in the continental United States since 1977. Then, in 2013, SCA abruptly became a serious pest of U.S. sorghum and is now a sorghum pest in 22 states across the continental United States. Changes in insect-associated microbial community composition are known to influence host-plant range in aphids. In this study, we assessed whether changes in microbiota composition may explain the SCA outbreak in U.S. sorghum. We characterized the SCA bacterial microbiota on sugarcane and grain sorghum in four U.S. states, using a metabarcoding approach. In addition, we used taxon-specific polymerase chain reaction (PCR) primers to screen for bacteria commonly reported in aphid species. As anticipated, all SCA harbored the primary aphid endosymbiont Buchnera aphidicola, an obligate mutualistic bacterial symbiont. Interestingly, none of the secondary symbionts, facultative bacteria typically associated with aphids (e.g., Arsenophonus, Hamiltonella, Regiella) were present in either the metabarcoding data or PCR screens (with the exception of Rickettsiella and Serratia, which were detected by metabarcoding at low abundances <1%). However, our metabarcoding detected bacteria not previously identified in aphids (Arcobacter, Bifidobacterium, Citrobacter). Lastly, we found microbial host-associated differentiation in aphids that seems to correspond to genetically distinct aphid lineages that prefer to feed on grain sorghum (MLL-F) versus sugarcane (MLL-D).

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Impact of Planting Date on Melanaphis sacchari (Hemiptera: Aphididae) Population Dynamics and Grain Sorghum Yield

Journal of Economic Entomology ◽

10.1093/jee/toz230 ◽

2019 ◽

Vol 112 (6) ◽

pp. 2731-2736 ◽

Cited By ~ 2

Author(s):

Nicholas J Seiter ◽

Anne D Miskelley ◽

Gus M Lorenz ◽

Neelendra K Joshi ◽

Glenn E Studebaker ◽

...

Keyword(s):

Population Dynamics ◽

Field Experiments ◽

The United States ◽

Grain Sorghum ◽

Planting Date ◽

Melanaphis Sacchari ◽

Planting Dates ◽

Sugarcane Aphid ◽

Aphid Feeding ◽

The Impact

Abstract The sugarcane aphid, Melanaphis sacchari (Zehntner) (Hemiptera: Aphididae), has become a major pest of grain sorghum, Sorghum bicolor (L.) Moench, in the United States in recent years. Feeding by large densities of sugarcane aphids causes severe damage, which can lead to a total loss of yield in extreme cases. Our objective was to determine the effect of grain sorghum planting date on sugarcane aphid population dynamics and their potential to reduce yields. We conducted field experiments from 2015 to 2017 in which an aphid-susceptible grain sorghum hybrid was planted at four different dates, which encompassed the typical range of planting dates used in Arkansas production systems. Plots were either protected from sugarcane aphid feeding using foliar insecticide sprays, or left untreated to allow natural populations of sugarcane aphids to colonize and reproduce freely. Planting date impacted both the magnitude and severity of sugarcane aphid infestations, with the highest population densities (and subsequent reductions in sorghum yield) generally occurring on plots that were planted in May or June. Sugarcane aphid feeding reduced yields in the untreated plots in two of the four planting date categories we tested. Earlier planting generally resulted in less sugarcane aphid damage and improved yields compared with later planting dates. While the effect of planting date on sugarcane aphid populations is likely to vary by region, sorghum producers should consider grain sorghum planting date as a potential cultural tactic to reduce the impact of sugarcane aphid.

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