Dry matter yield, persistence and three parameters of nutritive value were determined in two perennial ryegrass (Lolium perenne L.) genotypes either infected with a lolitrem B-free fungal endophyte or not infected, over a fouryear period at two different locations in north-west Spain. The endophyte did not influence the productivity or persistence of perennial ryegrass in the four years of study. Insufficiently stressful conditions could explain these results. The nutritive value of the plants was not influenced by endophyte infection, except for organic matter digestibility and water-soluble carbohydrates on some occasions (P

Ergovaline concentrations in two perennial ryegrass genotypes (EI 19 and EI24) infected with one lolitrem B-free fungal endophyte were determined over a 3-year period at two different locations in north-west Spain. There was a significant sampling date effect over 3 years and two locations (P < 0.05). The mean ergovaline concentrations ranged from 0.06 ppm in early spring to 0.57 ppm in June. EI19 genotype had significantly (P < 0.05) higher ergovaline concentrations (0.37 ppm, SE = 0.09) than EI24 genotype (0.33 ppm, SE = 0.08) only at one location in year 2000. Under north-west Spanish conditions, ergovaline levels obtained in this study were not so high to reach values potentially toxic for animals. The results presented in this paper suggest that agriculturally useful ryegrass endophyte associations can be developed free from lolitrem B, and which do not accumulate excessive concentrations of ergovaline.

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National Laboratory-Numerous studies have demonstrated the importance of the leading edge vortex (LEV) in enhancing lift production during hovering flight for a hummingbird. Almost all of these experiments have been performed under laminar inflow conditions without the presence of transient flow phenomena (e.g. gust). And yet, real-life ornithopters in the field have to routinely tackle gust and directional changes in the wind. In this talk, preliminary results from an investigation of the flow field modulation around a hummingbird wing under well-controlled gusty conditions are presented. Using a 2-degree of freedom robotic hummingbird model wing mounted on a translation stage, conditions replicating a gust impacting a wing are created at the NMSU water channel facility. Phase-locked PIV velocity measurements were obtained around the wing in the presence of gusts varying from 5-30% of the mean tangential wing velocity. These measurements, in combination with force and moment measurements from a six-axis load cell, are used to understand transient flow phenomena induced by the gust, and their effect on the net thrust and lift forces on the robot's wings over a range of Reynolds number (1400