Submitted to: Journal of Genetics and Breeding
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/31/2001
Publication Date: 1/31/2001
Citation: Ledbetter, C.A., Palmquist, D.E. Evaluation of advanced almond (Prunus amygdalus Batsch) selections relative to the commercial almond cultivars Mission, Nonpareil and Padre. II. Vegetative and carpological characteristics
Interpretive Summary: California's 1.1 billion dollar almond industry is dependent upon bees to cross-pollenize the 450,000+ acres of trees each year. Climatic factors can cause problems with bees and affect the annual yield of almonds. The use of specific almond varieties to optimize cross-pollenization can benefit in boosting annual nut yield. Almond selections from a breeding program have been evaluated for their specific capacity to match bloom periods and become effective pollenizers for important almond varieties. Several almond selections were identified that effectively pollenize the important Nonpareil variety. The development and utilization of new and efficient pollenizers for Nonpareil will ensure that yield will not be limited by problems during the bloom period.
Technical Abstract: Multivariate studies compared vegetative and carpological variables of almond (Prunus amygdalus Batsch) cultivars Mission, Nonpareil and Padre with 24 almond accessions from a breeding program. K-means cluster analysis indicated that eight of the 12 evaluated vegetative variables, and 23 of the 27 evaluated carpological variables contributed significantly (p = 0.05) to the variability within the almond collection. Highest F-ratios of the vegetative variables were obtained for maximum leaf blade width (p = 0.01) and leaf luminosity (p = 0.01). Pellicle luminosity (p= 0.01) and kernel length: thickness ratio (p = 0.01) were the two carpological variables with the highest numeric F-ratios. Multivariate analysis of variance (MANOVA) of both the vegetative and carpological variables reinforced the K-means cluster analysis showing that the almond collection could be divided into four specific clusters based on either the significant vegetative or carpological characters. Placement of Mission and Padre kernels in the same marketing class was confirmed though K-means cluster analysis. Eight of the advanced almond selections clustered with Nonpareil based on variability expressed in carpological characters.