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Emma L. Locke*, Cecil Stushnoff, Joyce C. Pennycooke, and Michelle Jones

Salinity, drought and temperature frequently limit crop productivity. Transgenic Petunia ×hybrida cv. Mitchell with altered endogenous raffinose family oligosaccharides (RFO) due to over-expression (sense) or under-expression (antisense) of the tomato α-galactosidase gene show that antisense increases in RFO are associated with greater tolerance to freezing stress (Pennycooke et al., 2003). Because vegetative propagules of these antisense lines rooted and established more quickly than their sense counterparts, we hypothesized that antisense lines would also respond to salinity and wilting stress. Salinity treatment plants were exposed to 50-200 mm NaCl graduated 25 mm every 3 days and held at 200 mm for 13 days. Dry-down treatments were watered to pot capacity, then not watered until the onset of wilting. This was repeated in cycles for 26 days. Data were collected on plant growth, root/shoot ratios, and leaf water potential. Fresh and dry weights in four of the six antisense lines exceeded the wild type and sense lines. Osmotic potential for salinity and dry-down plants was 160% to 220% higher than control plants. Pearson correlations revealed that higher osmotic potential was partially associated with higher fresh weight (r = 0.7214, P = 0.02) and root/shoot ratios (r = -0.7414, P = 0.02) in salinity stressed plants. In the dry-down drought stressed plants, osmotic potential was not associated with fresh weight (r = 0.3364, ns) nor root/shoot ratio (r = -0.0431, ns). Salinity stress reduced root mass compared to control and dry down plants. Sense plants grew slowly and were highly variable.

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Manfredo J. Seufferheld, Cecil Stushnoff, John Fitzpatrick, and Philip L. Forsline

Cryopreservation of woody-plant, dormant buds may provide cost-effective, long-term, back-up conservation of germplasm for vegetatively propagated crops that are presently maintained as trees in field gene banks. Dormant buds can be recovered quickly by grafting to dwarfing rootstocks, thus producing flowers for breeding purposes, with minimum potential for inducing somaclonal variants. These attributes are essential to preserve the clonal integrity of unique gene combinations such as those found in tree fruit crops. Previous research has shown that dormant buds from cold-hardy apples can be recovered from storage in liquid nitrogen (LN) with high survival rates (80% to 100%) using controlled desiccation and slow freezing before immersing in LN. On the other hand, dormant buds from cold-tender taxa and buds collected at less than optimal stages for desiccation and freezing have much lower (0% to 50%) survival rates. We increased survival of cold-tender taxa by using a modified vitrification procedure. Dormant apple buds from tender and hardy cultivars were perfused with modified PVS [15% (w/v) ethylene glycol, 15% (w/v) propylene glycol, 7% (w/v) DMSO, and 15% (w/v) glycerol in 0.5 m sorbitol]. Toxicity from the PVS was reduced by dilution soaking in 1 m sorbitol, 0.2 m raffinose, and 15 mm CaCl2 before and after quench-freezing and slow-freezing cryopreservation. Up to 100% of some cold-tender taxa survived. In addition, xylem ray parenchyma tissues that supercool and are normally killed at about -40C with the desiccation protocol survived this vitrification procedure.

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Erik J. Landry and David J. Wolyn

concentrations ( Livingston, 1996 ; Patton et al., 2007a , 2007b ). Compounds such as proline, simple sugars, certain proteins, and oligosaccharides such as raffinose and fructan ( Alden and Hermann, 1971 ) are osmolites with cryoprotective properties. Proline

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Mahmoud Panjtandoust and David J. Wolyn

on most dates ( Fig. 6D ). JG did not differ from UC and GM on most sampling dates. Sucrose levels of rhizomes were three to five times those in storage roots in both years. Raffinose. In 2012, rhizome raffinose concentrations decreased from the first

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Yosef Burger and Arthur A. Schaffer

appears to be controlled by the metabolism of carbohydrates in the fruit sink itself ( Hubbard et al., 1989 ; Lester et al., 2001 , Schaffer et al., 1996 , 2000 ). Sucrose and the galactosyl–sucrose oligosaccharides, raffinose and stachyose, are

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Samson Zeray Tesfay, Sakhile Mathe, Albert T. Modi, and Tafadzwanashe Mabhaudhi

in between subsequent harvests. Table 1. Water-soluble nonstructural carbohydrates accumulation by African and exotic leafy vegetables across different weeks after transplanting (WAT). Exceptionally, raffinose, a sugar alcohol was only detected for

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Penelope F. Measham, Audrey G. Quentin, and Nicholas MacNair

., 2012 ; Marquat et al., 1999 ). A pivotal paper ( Marquat et al., 1999 ) showed that the sucrose stored in buds of peach ( Prunus persica ) was used during dormancy release to synthesize the sorbitol and raffinose that are required for bud burst

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Bing Liu, Hong Zhou, Sha Cao, Yi-ping Xia, and Rajeev Arora

, raffinose, kestose, galactose, etc.) during seasonal acclimation and deacclimation ( Pagter et al., 2008 , 2011 ). In all these studies, loss of TSS was positively correlated with deacclimation. Our data reinforce previous observations and indicate a

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Mengmeng Gu, Curt R. Rom, James A. Robbins, and Derrick M. Oosterhuis

, galactose, glucose, mannose, maltose, trehalose, sucrose, and raffinose), organic acids (shikimic acid, malic acid, quinic acid, citric acid, salicylic acid, and succinic acid), polyols (arabitol, myoinositol, mannitol, and xylitol), and mineral nutrients (P

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Ken Takahata and Hiroyuki Miura

of raffinose was added as an internal standard to each thawed sample that was then neutralized with a 1% sodium hydroxide solution and filtered through a membrane filter (0.45 μm). The filtrate was used for the sugar analyses. Another series of thawed