RNA-seq analysis of two genealogically linked South African Diuraphis noxia biotypes

RNA was extracted from all instar (insect developmental) stages for both D. noxia biotypes SA1 and SAM with the purpose to capture as many expressed transcripts as possible. South African D. noxia biotype SA1 is known to be the least virulent aphid, while its offspring, the South African D. noxia biotype SAM is the most virulent. The overall purpose of the experiment was to establish a baseline availability of transcripts to the aphids as well as help improve on current genome assemblies. Three biological replicates of 100 aphids each was collected from both biotypes SA1 and SAM that were respectively reared on preference host cultivars. Whole aphids were flash frozen in liquid nitrogen, ground to a powder with micro pistils and RNA was extracted making use of a Qiagen RNeasy kit. Library preparation for sequencing was performed using an Illumina TruSeq Stranded mRNA LT Sample Prep Kit following the TruSeq Stranded mRNA Sample Preparation Guide, Part # 15031047 Rev. E protocol. The replicate samples from the SAM biotype yielded between 120 – 140 million 100bp PE reads and the replicate samples from the SA1 biotype yielded between 113 – 137 million 100bp PE reads (with a Q20 phred score above 98% for all replicates) after sequencing on the NovaSeq6000 system. De novoassembly was performed making use of the Trinity package. Overall design: Assessing and comparing transcripts produced from 2 genealogically linked Diuraphis noxia biotypes that greatly differ in their virulence to resistant wheat cultivars. 3 individual replicates from each biotype (SA1 and SAM) were collected (total of 6 samples) each consisting of 100 aphids of varying instar growth stages.