Predicting anthesis date of perennial ryegrass (Lolium perenne L.) with growing degree‐days at heading

The agronomic significance of heading date in crop species is well documented; however, the date of anthesis is often less emphasized even though it has important applications for seed quality and yield. Moreover, the relationship between heading and anthesis is not well defined. We propose that growing degree‐days to heading can be used as a good predictor of anthesis date. Using a broad range of 520 diploid perennial ryegrass accessions, anthesis was found to be highly correlated with growing degree‐days to heading, and growing degree‐days to heading could be used to predict anthesis date in historical data sets collected over many years. The ability to adequately predict anthesis will allow seed‐producing farmers to improve seed quality by identifying times when high disease pressure will coincide with anthesis, thus allowing control measures to be applied.     

Stones and Organic Mulches Improve the Quercus Ilex L. Afforestation Success Under Mediterranean Climatic Conditions

This work studies the influence of two mulching treatments on soil properties and the field performance of afforested holm‐oak seedlings (Quercus ilex L. subsp. ballota (Desf.) Samp.) nine years after outplanting. Mulching treatments composed of stones, forest debris, and an untreated control were randomly applied to 180 seedlings (n = 60) in January 2001 at the bed level (1 × 1 m) in an abandoned agricultural field in SE Spain. Survival, growth measured by means of leaf area, and nutrient concentrations in leaves and soil were measured. Both mulches provided higher survival and greater leaf‐area growth than the control, but did not differ in leaf‐nutrient concentration. Most of the analysed soil variables were not affected by the mulching treatments at the end of the study period, and, therefore, the soil properties changes by mulching might be slower than expected under semi‐arid conditions. Copyright © 2013 John Wiley & Sons, Ltd.