Thermal biology of Tuta absoluta: demographic parameters and facultative diapause

Journal of Pest Science - The South American tomato pinworm, Tuta absoluta, (SATP) is now a devastating pest worldwide of crops in the family Solanaceae. Most prior studies of SATP’s thermal...     

Molecular marker-based genetic linkage map of a diploid banana population (Musa acuminata Colla)

A well-saturated genetic linkage map is valuable for fundamental and applied genetic research. Genetic linkage maps of two half-sib diploid banana populations were constructed using allele-specific-polymerase chain reactions (AS-PCRs), diversity array technology (DArT), and simple sequence repeat (SSR) markers. Molecular maps were produced for each parent using the pseudo-testcross mapping strategy. The first maternal map (6142-1, 81 individuals) consisted of 231 markers divided as followed: 121 DArT, 106 SSR and 4 AS-PCR markers in 15 linkage groups (LGs) covering 670?cM. The second maternal map (6142-1-S, 58 individuals) contained a total of 152 markers including 71 DArTs, 79 SSRs, and 2 AS-PCRs mapped to 16 LGs that spanned 698?cM. The combined paternal map (139 individuals) comprised 316 markers (196 DArTs, 117 SSRs and 3 AS-PCRs) distributed over 15 LGs with a total map length of 1,004?cM. While distorted segregation of some markers was observed in all maps, this was much more frequent for the male parent. Homology between maps was assessed using common markers. While there was generally good congruity with regard to marker order across maps, incongruity in other cases may reflect chromosomal rearrangement events such as inversions, translocations, or deletions. The new banana map can provide a better understanding of the Musa genome and could be used for the identification of economically important traits and improvement of breeding strategies.     

Evidence of genotype–diet interactions in the response of rainbow trout (Oncorhynchus mykiss) clones to a diet with or without fishmeal at early growth

This study examined the genetic variability and genotype × diet interactions during early growth (initial mean body weight 1.2 g) among seven heterozygous clones of rainbow trout, Oncorhynchus mykiss. The clones were hand-fed a diet containing either fishmeal or plant proteins during a 49-day trial divided into two periods (P1, 26 days, and P2, 23 days). Weight, variation of weight within clone, feed intake, feed efficiency and mortality were calculated for both periods.There was a highly significant effect of diet and of clone for all traits at both periods, except for feed efficiency and mortality at P1. Highly significant interactions between diet and clone were also recorded for all these traits, except for mortality at P1. The occurrence of genotype × diet interactions when feeding juvenile rainbow trout with an all plant-protein diet indicates that a highly performing genotype on a fishmeal diet may perform poorly when fed a plant-protein diet. Interactions were found for the two major determinants of growth, i.e. feed intake and feed efficiency, showing that the dietary response differs according to the genotype. Monitoring of the within-clone variability of weight showed that a plant-based diet is likely to enhance the overall phenotypic variance in a population, whatever its initial genetic variability.     

GRIP deuterium excess reveals rapid and orbital-scale changes in Greenland moisture origin

The Northern Hemisphere hydrological cycle is a key factor coupling ice sheets, ocean circulation, and polar amplification of climate change. Here we present a Northern Hemisphere deuterium excess profile covering one climatic cycle, constructed with the use of delta18O and deltaD Greenland Ice Core Project (GRIP) records. Past changes in Greenland source and site temperatures are quantified with precipitation seasonality taken into account. The imprint of obliquity is evidenced in the site-to-source temperature gradient at orbital scale. At the millennial time scale, GRIP source temperature changes reflect southward shifts of the geographical locations of moisture sources during cold events, and these rapid shifts are associated with large-scale changes in atmospheric circulation.