Emerging New Crop Pests: Ecological Modelling and Analysis of the South American Potato Psyllid Russelliana solanicola (Hemiptera: Psylloidea) and Its Wild Relatives

© 2017 Syfert et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

Translocation of newly-assimilated carbon in the vegetative shoot of olive

Measurements of phloem transport within vegetative shoots of three-year old olive (Olea europaea L.) plants grown in containers were made using (CO2)-C-11. The short-lived C-11 isotope has a half-life of 20.4 min and allows in vivo monitoring of newly-assimilated carbon. Fully-expanded leaves differing in their position along the shoot (node 1, 2, 3 and 4 from the apex) were pulse-labelled with (CO2)-C-11 in an assimilation cuvette connected to a semi-closed gas exchange system at 25 degreesC, photosynthetically active radiation at 400 mumol m(-2) s(-1), and CO2 of 380 mul l(-1). Labelling started about 4 h after the beginning of the photoperiod and leaves were actively photosynthesizing. There were clear differences in the patterns of export out of the labelled leaf depending on leaf position. No evidence of short-term export was found when the youngest fully-expanded leaf was labelled. Labelling the second youngest leaf resulted in a strong tracer pulse in the portion of the stem immediately proximal to the petiole of the labelled leaf, but no activity a further 5 cm below; only a very small amount of radioactivity was detected in the acropetal direction. When the 4(th) youngest leaf was labelled, the radioactive signal was strong in both detectors placed basipetally, but not in the acropetal direction. Flows of newly-assimilated carbon showed typical diurnal courses, with an increase in the exported radioactivity in the afternoon (12 h after the beginning of the photoperiod)

Mitochondrial DNA diversity of the Asian moon scallop, Amusium pleuronectes (Pectinidae), in Thailand

Sequence variation of the mitochondrial DNA 16S rRNA region of the Asian moon scallop, Amusium pleuronectes, was surveyed in seven populations along the coast of Thailand. A total of 16 unique haplotypes were detected among 174 individuals with a total 27 variable sites out of 534 bp sequenced. The mitochondrial haplotypes grouped into two distinct arrays (estimated to differ by about 2.62% to 2.99% nucleotide divergence) that characterized samples collected from the Gulf of Thailand versus the Andaman Sea. Low levels of intrapopulation variation were observed, while in contrast, significant divergence was observed between populations from the Gulf of Thailand and Andaman Sea. Results of AMOVA reveal a high F ST value (0.765) and showed that the majority of the total genetic variance (76.03%) occurred among groups (i.e., Andaman Sea and the Gulf of Thailand) and little among populations within the group (0.52%) and within populations (23.45%). The genetic differentiation between the populations recorded in the present study is similar to that observed in a variety of marine species in the Indo-Pacific. The implications of the findings for management of A. pleuronectes genetic resources in Thailand are discussed. </div