An empirical evaluation of instantaneous and one-zero sampling of chimpanzee behavior

The behavior category in progress at theend of every 15 seconds of observation of chimpanzee behavior was recorded (instantaneous sampling) as was the occurrence or nonoccurrence of all defined categoriesduring every 15 second observation interval (one-zero sampling). The scores obtained using the above procedures were then correlated with the percent of net observation time, hourly rate, and mean bout duration of the behavior categories. One-zero sampling scores correlated very strongly with percent of net observation time and moderately with hourly rate and mean bout duration. Instantaneous sampling scores correlated very strongly with percent of net observation time and moderately with hourly rate and mean bout duration.     

The plant beneficial effects of Metarhizium species correlate with their association with roots

Metarhizium species have recently been found to be plant rhizosphere associates as well as insect pathogens. Because of their abundance, rhizospheric Metarhizium could have enormous environmental impact, with co-evolutionary implications. Here, we tested the hypothesis that some Metarhizium spp. are multifactorial plant growth promoters. In two consecutive years, corn seeds were treated with entomopathogenic Metarhizium spp. and field tested at the Beltsville Facility in Maryland. Seed treatments included application of green fluorescent protein (GFP)-tagged strains of Metarhizium brunneum, Metarhizium anisopliae, Metarhizium robertsii, and M. robertsii gene disruption mutants that were either avirulent (Δmcl1), unable to adhere to plant roots (Δmad2), or poorly utilized root exudates (Δmrt). Relative to seeds treated with heat-killed conidia, M. brunneum, M. anisopliae, and M. robertsii significantly increased leaf collar formation (by 15, 14, and 13 %), stalk length (by 16, 10, and 10 %), average ear biomass (by 61, 56, and 36 %), and average stalk and foliage biomass (by 46, 36, and 33 %). Their major impact on corn yield was during early vegetative growth by allowing the plants to establish earlier and thereby potentially outpacing ambient biotic and abiotic stressors. Δmcl1 colonized roots and promoted plant growth to a similar extent as the parent wild type, showing that Metarhizium populations are plant growth promoters irrespective of their role as insect pathogens. In contrast, rhizospheric populations and growth promotion by Δmrt were significantly reduced, and Δmad2 failed to colonize roots or impact plant growth, suggesting that colonization of the root is a prerequisite for most, if not all, of the beneficial effects of Metarhizium.     

Effect of dietary fatty acids differing by chain lengths and omega series on the growth and lipid composition of turbot Scophthalmus maximus L.

1. A previous paper (Gatesoupe et al., 1977) showed that turbot had a specific requirement for omega 3HPUFA since equivalent dietary amounts of 18:3 omega 3 or omega 3HPUFA (0.55% of the diet) did not lead to the same growth performances. 2. In the present paper, we demonstrated that fish given a high level of dietary 18:3 omega 3 (3.7% of the diet), without omega 3HPUFA, presented better growth than those offered a lower level of 18:3 omega 3, and almost the same performances as fish receiving 0.57% omega 3HPUFA. 3. This suggested that turbot, like trout, might be able to use the 18:3 omega 3 as a precursor of the omega 3 series. Furthermore, according to the present relatively short-term experiment, elongation-desaturation reactions of the omega 3FA did not appear to be reduced with low dietary omega 3FA levels. 4. On the other hand, these types of reactions seemed to be totally missing with the 18:2 omega 6. Thus, it may be assumed that there was no direct relationship between growth and omega 3 elongating-desaturating activities, and that omega 3 lowering fish body content was not the cause, or at least not the only cause, of poor growth in long-term experiments.