Biological control (biocontrol) of crop pests is a sustainable alternative to the use of biodiversity and organismal health‐harming chemical pesticides. Aphids can be biologically controlled with parasitoid wasps; however, variable results of parasitoid‐based aphid biocontrol in greenhouses are reported. Aphids may display genetically encoded (endogenous) defences that increase aphid resistance against parasitoids as under high parasitoid pressure there will be selection for parasitoid‐resistant aphids, potentially affecting the success of parasitoid‐based aphid biocontrol in greenhouses. Additionally, aphids may carry secondary bacterial endosymbionts that protect them against parasitoids. We studied whether there is variation in either of these heritable elements in aphids in greenhouses of sweet pepper, an agro‐economically important crop in the Netherlands that is prone to aphid pests and where pest management heavily relies on biocontrol. We sampled aphid populations in organic (biocontrol only) and conventional (biocontrol and pesticides) sweet pepper greenhouses in the Netherlands during the 2019 crop growth season. We assessed the aphid microbiome through both diagnostic PCR and 16S rRNA sequencing and did not detect any secondary endosymbionts in the two most encountered aphid species, Myzus persicae and Aulacorthum solani. We also compared multiple aphid lines collected from different greenhouses for variation in levels of endogenous‐based resistance against the parasitoids commonly used as biocontrol agents. We found no differences in the levels of endogenous‐based resistance between different aphid lines. This study does not support the hypothesis that protective endosymbionts or the presence of endogenous resistant aphid lines affects the success of parasitoid‐based biocontrol of aphids in Dutch greenhouses. Future investigations will need to address what is causing the variable successes of aphid biocontrol and what (biological and management‐related) lessons can be learned for aphid control in other crops, and biocontrol in general.

1Nesidiocoris tenuis (Reuter) is an efficient predatory biological control agent used 2 throughout the Mediterranean Basin in tomato crops but regarded as a pest in 3 northern European countries. Belonging to the family Miridae, it is an economically 4 important insect yet very little is known in terms of genetic information -no published 5 genome, population studies, or RNA transcripts. It is a relatively small and long-lived 6 diploid insect, characteristics that complicate genome sequencing. Here, we 7 circumvent these issues by using a linked-read sequencing strategy on a single female 8 N. tenuis. From this, we assembled the 355 Mbp genome and delivered an ab initio, 9 homology-based, and evidence-based annotation. Along the way, the bacterial 10 "contamination" was removed from the assembly, which also revealed potential 11 symbionts. Additionally, bacterial lateral gene transfer (LGT) candidates were 12 detected in the N. tenuis genome. The complete gene set is composed of 24,688 13 genes; the associated proteins were compared to other hemipterans (Cimex 14 lectularis, Halyomorpha halys, and Acyrthosiphon pisum), resulting in an initial 15 assessment of unique and shared protein clusters. We visualised the genome using 16 various cytogenetic techniques, such as karyotyping, CGH and GISH, indicating a karyotype of 2n=32 with a male-heterogametic XX/XY system. Additional analyses 18 include the localization of 18S rDNA and unique satellite probes via FISH techniques. 19Finally, population genomics via pooled sequencing further showed the utility of this 20 genome. This is one of the first mirid genomes to be released and the first of a mirid 21 biological control agent, representing a step forward in integrating genome 22 sequencing strategies with biological control research. 23 Introduction 24Hemiptera is the fifth largest insect order and the most speciose hemimetabolous order 25 with over 82,000 described species (Panfilio and Angelini, 2018). While recent 26 sequencing projects have presented a variety of information about hemipteran 27 genomes, large families such as the plant bugs Miridae still lack genomic resources, 28 with the exception of transcriptomic resources for some members (Tian et al., 2015), 29 and the more recent genome of Apolygus lucorum, a mirid pest that has a publicly 30 available genome as of December 2019 (NCBI BioProject PRJNA526332). With the 31 exception of A. lucorum, the lack of genomic resources for Miridae is in spite of the 32 diverse life histories present, as it contains not only some of the most notorious 33 agricultural pests but also predators that are often used in biological control (van 34 Lenteren et al., 2018). In addition, Hemiptera are known for their intriguing karyotype 35 evolution involving holocentric (holokinetic) chromosomes but there is a lack of 36 cytogenetic information on Miridae. The absence of the ancestral TTAGGn telomeric 37 repeat have been reported for mirids Macrolophus spp., Deraeocoris spp., and 38

1Trichogramma brassicae (Bezdenko) are egg parasitoids that are used 2 throughout the world as biological control agents and in laboratories as model 3 species. Despite this ubiquity, few genetic resources exist beyond COI, ITS2, and 4 RAPD markers. Aided by a Wolbachia infection, a wild-caught strain from 5Germany was reared for low heterozygosity and sequenced in a hybrid de 6 novo strategy, after which several assembling strategies were evaluated. The 7 best assembly, derived from a DBG2OLC-based pipeline, yielded a genome of 8 235 Mbp made up of 1,572 contigs with an N50 of 556,663 bp. Following a 9 rigorous ab initio-, homology-, and evidence-based annotation, 16,905 genes 10 were annotated and functionally described. As an example of the utility of the 11 genome, a simple ortholog cluster analysis was performed with sister species T. 12

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