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In this study, we first construct an age-stage, two-sex life table for onion maggot, Delia antiqua, grown on three host plants: onion, scallion, and garlic. We found that onion is the optimal host for this species and populations grown on onion have maximum fecundity, longest adult longevity and reproduction period, and the shortest immature developmental time. In contrast, the fecundity on other hosts was lower, particularly on garlic, but these crops can also serve as important secondary hosts for this pest. These data will be useful to the growers to develop specific integrated management programs for each of hosts. We also compared the demographic analyses of using individually-reared and group-reared methods. These two methods provided similar accurate outcomes for estimating insect population dynamics for this species. However, for gregarious species, using the individually-reared method to construct insect life tables produces inaccurate results, and researchers must use group-reared method for life table calculations. When studying large groups of insect, group-reared demographic analysis for age-stage, two-sex life table can also simplify statistical analysis, save considerable labor, and reduce experimental errors.

Male and macropterous female of Ctenothrips smilax Bhatti, 1976 are first described and illustrated, together with brachypterous female which has already been reported by Bhatti in 1976. The species was firstly reported from China. All specimens are deposited in the Entomological Museum of Northwest A&F University (NWAFU).

Four species of the genus Ophthalmothrips Hood are recorded from Mainland China, including the descriptions of one new species. O. yunnanensis sp. nov. (Yunnan). Illustrations of the new species and a key to all species of genus Ophthalmothrips from Mainland China are provided, along with a checklist of the known species of the genus.

The genus Semelaspidus MacGillivray, 1921 is reviewed, and one new species, Semelaspidus multiporus sp. nov., from China, is described. In addition, photographs and illustrations of the new species, and a key to all species of the genus are provided.

Biotransformation enzymes are found in insect antennae and play a critical role in degrading xenobiotics and odorants. In Cydia pomonella, we identified 26 biotransformation enzymes. Among these enzymes, twelve carboxylesterases (CXEs), two aldehyde oxidases (AOXs) and six alcohol dehydrogenases (ADs) were predominantly expressed in antennae. Each of the CpomCXEs presents a conserved catalytic triad "Ser-His-Glu", which is the structural characteristic of known insect CXEs. CpomAOXs present two redox centers, a FAD-binding domain and a molybdenum cofactor/substrate-binding domain. The antennal CpomADs are from two protein families, short-chain dehydrogenases/reducetases (SDRs) and medium-chain dehydrogenases/reducetases (MDRs). Putative catalytic active domain and cofactor binding domain were found in these CpomADs. Potential functions of these enzymes were determined by phylogenetic analysis. The results showed that these enzymes share close relationship with odorant degrading enzymes (ODEs) and resistance-associated enzymes of other insect species. Because of commonly observed roles of insect antennal biotransformation enzymes, we suggest antennal biotransformation enzymes presented here are candidate that involved in degradation of odorants and xenobiotics within antennae of C. pomonella.

Ribosomal protein genes have become widely used as markers for phylogenetic studies and comparative genomics, but they have not been available in fish. We have cloned and sequenced a complete set of all 47 60S ribosomal protein cDNAs from channel catfish (Ictalurus punctatus), of which 43 included the complete protein encoding regions. Most ribosomal protein mRNAs in channel catfish are highly similar to their mammalian counterparts. However, L4, L14, and L29 are significantly shorter in channel catfish than in mammals due to deletions in the 3' end of the gene. Two distantly related L5 cDNAs, L5a and L5b, were found in channel catfish. L5a is more similar to L5 in other vertebrates, while L5b showed significant levels of divergence, suggesting independent evolution of the two L5-encoding genes. The 47 ribosomal protein genes are generally highly expressed and together account for 11-14% of overall gene expression, depending on the tissues. Expression levels were highly variable both within a single tissue among different ribosomal protein genes, and among tissues with regard to a single ribosomal protein gene. Strong tissue preference expression was also observed for some ribosomal proteins. This set of ribosomal protein gene sequences represents one of the most complete sets from any single organism and will aid in fish phylogenetic and comparative genomic studies.

Loyolaia Ananthakrishnan, a newly recorded genus of the subfamily Idolothripinae, is reported from China, with Loyolaia wuyiensis sp. n. is described. A key to all known species of this genus is provided.

Background EST sequencing is one of the most efficient means for gene discovery and molecular marker development, and can be additionally utilized in both comparative genome analysis and evaluation of gene duplications. While much progress has been made in catfish genomics, large-scale EST resources have been lacking. The objectives of this project were to construct primary cDNA libraries, to conduct initial EST sequencing to generate catfish EST resources, and to obtain baseline information about highly expressed genes in various catfish organs to provide a guide for the production of normalized and subtracted cDNA libraries for large-scale transcriptome analysis in catfish. Results A total of 17 cDNA libraries were constructed including 12 from channel catfish (Ictalurus punctatus) and 5 from blue catfish (I. furcatus). A total of 31,215 ESTs, with average length of 778 bp, were generated including 20,451 from the channel catfish and 10,764 from blue catfish. Cluster analysis indicated that 73% of channel catfish and 67% of blue catfish ESTs were unique within the project. Over 53% and 50% of the channel catfish and blue catfish ESTs, respectively, had significant similarities to known genes. All ESTs have been deposited in GenBank. Evaluation of the catfish EST resources demonstrated their potential for molecular marker development, comparative genome analysis, and evaluation of ancient and recent gene duplications. Subtraction of abundantly expressed genes in a variety of catfish tissues, identified here, will allow the production of low-redundancy libraries for in-depth sequencing. Conclusion The sequencing of 31,215 ESTs from channel catfish and blue catfish has significantly increased the EST resources in catfish. The EST resources should provide the potential for microarray development, polymorphic marker identification, mapping, and comparative genome analysis.

Ribosomal protein (RP) genes have become widely used as markers for phylogenetic studies and comparative genomics. However, they have not been available for evolutionary studies in fish although teleosts are the largest group of vertebrates with more than 23,000 species. Using a transcriptomic approach, we have cloned and sequenced 32 40S RP complementary DNAs (cDNAs) from channel catfish (Ictalurus punctatus), making them one of the most complete sets of 40S RP gene sequences from a single organism. Most 40S RPs in channel catfish are highly similar to their orthologues in mammalian species, but S19, S21, and S25 are highly divergent. Only one type of cDNA was found for all RP genes except S26 and S27, for which two cDNAs were found in channel catfish. Alternatively spliced transcripts for the S3 and alternatively polyadenylated transcripts for S19 and S21 were found. The 32 40S RP genes are generally highly expressed and together they account for 5.33-11.42% of expression depending on the tissues. Expression levels of the RP genes were highly variable both within a single tissue among different RP genes and among tissues with regard to a single RP gene. Taken together, these data strongly suggest post-transcriptional regulation of RP gene expression, particularly in consideration of the stoichiometry of their representation in ribosomes.

Previous molecular genetic studies on channel catfish (Ictalurus punctatus) have focused on limited number of genes and gene products. Recent advancement of molecular techniques made high throughput analysis of transcriptomes possible. As part of our transcriptome analysis of channel catfish, we have analyzed 1909 expressed sequence tags (ESTs) derived from a skin library. Of the 1909 ESTs analyzed, 1376 (72.1%) ESTs representing 496 unique genes had homologies with other organisms while 478 (25.0%) ESTs had no significant homologies and were designated as unknown. The remaining 55 (2.9%) EST clones were eliminated because of their low quality or short sequences. Of the 496 unique genes, 327 (65.9%) genes were singletons while 169 (34.1%) genes represented by two or more ESTs. A total of 1007 (52.8%) ESTs representing 235 unique genes matched previously reported channel catfish ESTs while 847 (44.4%) ESTs representing 261 unique genes were newly identified from this research. Functional categorization of the channel catfish genes indicated that the largest group was ribosomal proteins with 65 unique genes represented by 500 clones. The most abundantly expressed gene, the calcium binding protein ictacalcin, accounted for almost 5% of overall expression, indicating its important function in the skin. Sequence analysis of ESTs revealed the presence of 89 microsatellite-containing genes that may be valuable for future mapping studies.