Search results for " Prunus"

A simple, rapid extraction and assay procedure for the NAD+-dependent sorbitol dehydrogenase (SDH) in peach

1998

Sorbitol is the major photosynthetic product in peach. In sink tissues, sorbitol is converted to fructose via the NAD+-dependent sorbitol dehydrogenase (SDH). A new procedure is described that allows rapid, simple quantification of SDH activity in growing tissues. The procedure uses only 0.01 to 2.5 grams of fresh tissue per sample, such that a single shoot tip, a single root tip, or about 5 g of fruit flesh can be assayed for SDH activity. Storage of samples at 4 or -20 C° over night resulted in significant loss of enzyme activity. Thus, freshly harvested tissues were ground with sand in buffer at 2°C in a mortar and pestle, and the homogenate centrifuged @ 3000 ´ g to remove particulate m…

ADATTAMENTO ALLA GESTIONE BIOLOGICA DI CULTIVAR DI PESCO ( PRUNUS PERSICA L. BATSCH ) SICILIANE OTTENUTE ATTRAVERSO SELEZIONE MASSALE E INCROCIO.

2011

Roles of sorbitol and sucrose in growth and respiration of ‘Encore’ peach fruit in the three developmental stages

2002

In peach [Prunus persica (L.) Batsch (Peach Group)], both sorbitol and sucrose are utilized for source to sink carbon (C) transport, yet their specific functions in fruit growth and development remain unclear. Growth rate (GR), respiration rate (R), carbohydrate content, and the activities of sorbitol dehydrogenase (SDH), sorbitol oxidase (SOX), sucrose synthase (SS), acid invertase (AI), and neutral invertase (NI) were determined in ‘Encore’ peach fruit to study the specific functions of sorbitol and sucrose in each phase of fruit development (an early period of rapid cell division, a relatively inactive intermediate stage where endocarp (pit) hardening occurs, and a final swelling due to …

Contributo alla caratterizzazione morfologica del polline di Prunus avium L.

2012

Partitioning of Sorbitol and Sucrose Catabolism within Peach Fruit

2002

The peach (Prunus persica (L.) Batsch (Peach Group)) fruit is a sink organ comprised of different types of tissue, which undergoes three distinct developmental stages during the growth season. The objective of this study was to characterize the activity and partitioning of sorbitol and sucrose catabolism within 'Encore' peach fruit to determine whether the two forms of translocated carbon play different roles in the various fruit tissues and/or stages of development. Sorbitol catabolic activity was defined as the sum of NAD-dependent sorbitol dehydrogenase (SDH) and sorbitol oxidase (SOX) activities, whereas sucrose catabolic activity was defined as the sum of sucrose synthase (SS), soluble…

Effect of drought on sorbitol and sucrose metabolism in sinks and sources of peach

2000

In peach (Prunus persica [L.] Batsch.), sorbitol and sucrose are the two main forms of photosynthetic and translocated carbon and may have different functions depending on the organ of utilization and its developmental stage. The role and interaction of sorbitol and sucrose metabolism was studied in mature leaves (source) and shoot tips (sinks) of'Nemaguard' peach under drought stress. Plants were irrigated daily at rates of 100, 67, and 33% of evapotranspiration (ET). The relative elongation rate (RER) of growing shoots was measured daily. In mature leaves, water potential (ψ w ), osmotic potential (ψ s ), sorbitol-6-phosphate dehydrogenase (S6PDH, EC 1.1.1.200), and sucrose-phosphate synt…

Activities of Sucrose and Sorbitol Metabolizing Enzymes in Vegetative Sinks of Peach and Correlation with Sink Growth Rate

1999

Terminal portions of `Flordaguard' peach roots [Prunus persica (L.) Batsch] were divided into six segments and the activities of NAD+-dependent sorbitol dehydrogenase (SDH), sorbitol oxidase (SOX), sucrose synthase (SS), soluble acid invertase (AI), and soluble neutral invertase (NI) were measured in each segment 10, 15, and 20 days after seed germination. The same type of experiment was conducted with terminal portions of `Flordaguard' and `Nemaguard' peach shoots except that one of the six segments consisted of the leaflets surrounding the apex. Independent of the age of individual roots, activities of SDH and AI were consistently highest in the meristematic portion and decreased with tis…

Transport and partitioning of 13C-photoassimilate between peach fruiting shoots

2008

We used a non-intrusive method (13CO2 feeding) and a manipulative approach to see whether fruiting shoots in peach trees are autonomous or may import carbon from neighboring shoots under forced conditions, and whether the degree of autonomy is influenced by the source-sink relationship on the shoot. In three experiments, leaf to fruit ratio (L:F) of selected fruiting shoots was moderately (2005 and 2006) or strongly (extreme enforcing 2006) altered to either encourage or discourage movement of carbon from 13C-labeled sending shoots (SFS) to receiving fruiting shoots (RFS), both located on the same main scaffold of V-shaped peach trees. At stage I and III of fruit growth, fruit and shoot tip…

LOW VIGOR PEACH × ALMOND ROOTSTOCKS FOR INTENSIVE PEACH PLANTINGS IN MEDITERRANEAN ENVIRONMENTS

2014

A three-year trial was carried out to evaluate the vegetative and productive performance of five peach rootstocks of varied vigor. The study was conducted in south-western Sicily using 45 V-trained trees of 'Tropic Snow' peach planted in 2005 and grafted on GF677 and four low-vigor rootstocks selected at the Department of Agricultural, Food and Environmental Sciences, University of Pisa, namely IS5/8 (Polluce), IS5/19 (Castore), IS5/23, IS5/29. Trunk circumference, winter and summer pruning weight, number and mass of fruit were recorded from 2010 to 2012. All IS selections reduced trunk cross-sectional area (TCSA) and pruning weight compared to GF677 with IS5/23 inducing the highest reducti…

Carbohydrate Metabolism and Source-Sink Relationships in Peach

2011

A growing plant can be viewed as a collection of carbohydrate sinks competing with each other for the available photosynthate supplied by the exporting leaves. Differences in sink strength often result in changes in the ability of various organs to compete for the available food determining final tree growth. A series of experiments have been conducted in peach to study changes and regulation of carbohydrate metabolism in growing organs and get a better understanding of the link between carbohydrate metabolism, sink strength, carbon partitioning and overall tree growth. Along with sucrose, sorbitol represents the major photosynthetic product and the main form of translocated carbon in peach…