Blueberry fruit were harvested at commercial maturity from variety trials and shipped overnight to UC Davis. Fruit quality was evaluated upon receipt and after 6 and 20 days of cold storage at 0.5 °C in air shelf life. Firmness, external color, soluble solids, and titratable acidity were measured. Sensory evaluations were conducted by trained tasters to rate the blueberries for crispness, mealiness, sweetness, tartness, blueberry flavor, and off-flavors at harvest and again after 21 days of storage. Many of the blueberries increased in firmness during cold storage. Firmness at harvest tended to be softer in `Santa Fe' and `Jewel' and firmer in `Star'. Sensory data also found `Sharpblue' and `Southmoon' to be more firm; however the objective measurements did not agree. Overall, `Saphire' was low in sugars and acids, and `Jewell' and `Star' were high in acids. `Misty' and `Sharpblue' were consistently high in sugars and acids. Overall objective fruit quality ratings were highest for `Misty', `Sharpblue', and `Southmoon', and lowest for `Santa Fe'. Blueberry flavor was rated highest in `Jewell', `Star', and `Sharpblue', and lowest in `Santa Fe', `Saphire', `Misty', and `Emerald'. These data indicate that blueberry flavor may be closely tied to acid content, as most of the high-flavor varieties had high acid and many of the low-flavor varieties had low acid. Over 3 years, the varieties consistently rated highest for overall objective quality were `Misty' and `Southmoon'. `Star' was rated high for overall quality in 2 years and moderate in 1. `Jewell', `Star', and `Sharpblue' were rated highest in flavor. `Santa Fe' was ranked low in flavor quality in 2 out of 3 years. Selection of variety appears to have a strong influence on the sensory quality of the blueberries marketed.
Elizabeth Mitcham, William Biasi, Mark Gaskell, Ben Faber, and Ramiro Lobo
Deborah Pagliaccia, Georgios Vidalakis, Greg W. Douhan, Ramiro Lobo, and Gary Tanizaki
Hylocereus (Berger) Britton and Rose and Selenicereus (Berger) Britton and Rose are two genera of vine cacti, commonly named pitahaya, that produce fruit that are gaining in popularity as an exotic fruit in many countries. There has also been an increasing interest in these fruits because they can be grown in areas that are prone to drought and heat where other fruit production is not possible. However, there is significant taxonomic confusion regarding species within these genera as well as some uncertainty among named varieties. Amplified fragment length polymorphism (AFLP) was used to genotype a large pitahaya collection to determine if there was redundancy in some of the commonly named varieties as well as to assess the overall diversity of the collection. A total of 51 markers were scored from 230 accessions. Seven distinct clades were found with 126 putative clones but only three clades had high bootstrap (greater than 80%) support and one had moderate support (60%). Some of the differently named varieties were identical based on our analysis, but there was also genotypic diversity within putatively named varieties. The results of this study will help growers and researchers to choose genetically distinct accessions from the germplasm collection to investigate how different accessions perform in their growing regions.