Effects of light-diffusing plastic film on lettuce production and quality attributes

In general, plants grown under diffuse light yield higher biomass than those grown under direct light as a result of a more uniform distribution of the light across the plant canopy. We compared the effects of a light-diffusing plastic film and a clear plastic film on growth of Batavia lettuce (Lactuca sativa L.) in two greenhouses during five growth periods. Lettuce grown under the light-diffusing film were smaller (up to 36%) than control plants grown under the clear film, due to the fewer leaves per plant (up to 22%) and lower mean values of individual leaf area (up to 29%). The photosynthetically active radiations use efficiency was sometimes lower (up to 23%) in lettuces grown under the light-diffusing film. The pigment contents tended to be lower in plants grown under the light-diffusing plastic. The total macroelement contents of the lettuces grown under the light-diffusing plastic were up to 10% higher than in the lettuces grown under clear plastic, mainly as a result of higher leaf K contents (up to 19% higher). In addition, use of the light-diffusing plastic tended to increase leaf nitrate contents (by up to 23%). The leaf solid soluble content and acidity values were higher in the lettuces grown under the light-diffusing plastic, while leaf pH values were lower than in the control plants. The findings showed that the light-diffusing plastic was detrimental to production of compact heads of lettuce, and to some quality parameters such as nitrate and pigment contents. Nevertheless, open-leaf cultivars would likely show a different response to the diffuse ligh

Atypical/Nor98 scrapie in the Basque Country: a case report of eight outbreaks

Abstract Background Since 2002, an active surveillance program for transmissible spongiform encephalopathy in small ruminants in European Union countries allowed identification of a considerable number of atypical cases with similarities to the previously identified atypical scrapie cases termed Nor98. Case presentation Here we report molecular and neuropathological features of eight atypical/Nor98 scrapie cases detected between 2002 and 2009. Significant features of the affected sheep included: their relatively high ages (mean age 7.9 years, range between 4.3 and 12.8), their breed (all Latxa) and their PRNP genotypes (AFRQ/ALRQ, ALRR/ALRQ, AFRQ/AFRQ, AFRQ/AHQ, ALRQ/ALRH, ALRQ/ALRQ). All the sheep were confirmed as atypical scrapie by immunohistochemistry and immunoblotting. Two cases presented more PrP immunolabelling in cerebral cortex than in cerebellum. Conclusions This work indicates that atypical scrapie constitutes the most common small ruminant transmissible spongiform encephalopathy form in Latxa sheep in the Spanish Basque Country. Moreover, a new genotype (ALRQ/ALRH) was found associated to atypical scrapie.</p