A new spontaneous mutation of the pear variety Dr. Jules Guyot, named `IGE 2002', was selected from a pear growing area in Catalonia. The clone was established in vitro from a 40-year-old tree, a highly recalcitrant material unable to root by cuttings. An in vitro micropropagation protocol, with an average multiplication rate of 5, a 90% rooting, and an acclimation of 79% of the plantlets, was defined. Self-rooted plants were grown in two experimental stations, covering two distinct fruit growing areas. The main agronomic characteristics of the clone `IGE 2002' were evaluated during six seasons, 1997 to 2002. Blooming and harvest period were at a similar time than `Dr. Jules Guyot'. Soluble solids concentration and acidity are also similar to `Dr. Jules Guyot'. However, at the same harvest time, a lower fruit firmness of `IGE 2002' in comparison to `Dr. Jules Guyot' indicated an advanced ripening. In addition, a finer flesh texture of `IGE 2002' than `Dr. Jules Guyot', distinguished the former from the later variety. Important differences between both plot sites were found on cumulative fruit yield, fruit size, and fruit size distribution, of `IGE2002' grown on its own roots. However, the site did not affect the fruit quality parameters. Superior fruit yields were associated with higher vigor and yield efficiency of the self-rooted variety.
Almond (Prunus amygdalus Batsch.) blooming date is determined by the temperatures during the dormancy period, from the onset of endodormancy to just before blooming. In this work we have developed a model, based on several years data, to estimate the mean transition date from endodormancy to ecodormancy in 44 almond cultivars covering the whole range of almond bloom, through the significance of correlation coefficients between the temperatures occurring during dormancy and the date of full bloom. The estimation of this date for each cultivar has allowed the calculation of its chill and heat requirements. It was found that most cultivars have chilling requirements between 400 and 600 chill units, whereas the span of heat requirements was wider, from 5500 to 9300 growing degree hours Celsius. Some cultivars show high chilling requirements and low heat requirements whereas others show opposite requirements. These differences confirm the wide almond adaptability to different climatic conditions and offer the possibility of being utilized in breeding programs. The good fit shown by the application of this model in the prediction of bloom time may sustain its application in chilling and heat requirement estimation in other fruit species if blooming dates and climatic data for several years are available.
The almond ( Prunus amygdalus Batsch) breeding program of the Centro de Investigación y Tecnología Agroalimentaria of Aragón aims to develop new self-compatible and late-blooming cultivars to solve the main problem detected in Spanish almond
, 2006 ; Yao, 2012a ). Each branchlet can have from 20 to over 100 flowers depending on the cultivar. Branchlet growth, flower initiation, blooming, fruit setting, and fruitlet growth occur simultaneously. Because of the high nutrient competition
for regulating the flowering of sacred lotus have not been established. During the growing season, sacred lotus produces foliage leaves regularly at every node. The number of blooming flowers is generally much smaller than the number of foliage leaves
States Department of Agriculture Plant Genetic Resources Unit (USDA-PGRU, Geneva, NY, USA), include three trees previously characterized as early-blooming (including two extreme early-blooming) and three characterized as extreme late-blooming according to