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Background and aim: Despite the fact that bowel ultrasound (US) has recently been proved to be useful in the assessment of bowel diseases, uncertainty persists as to its diagnostic role [...]

Various diseases and conditions can cause bony defects in the maxillofacial region. Since microvascular bone graft transfers were introduced in 1970, new possibilities in reconstructive surgery have arisen. Various methods of treatment have been described for severely atrophic mandibles. These methods are: (1) the placement of four endosteal implants of short length, (2) the placement of a trans-mandibular implant (3) the placement of endosteal implants in combination with vertical distraction osteogenesis or (4) the placement of endosteal implants in combination with an onlay or interpositional bone graft. The patient was operated on to harvest bone for dental implant insertion at the Galeazzi Institute (Milan, Italy) in August 2016. He presented high resorption of edentulous mandible. Bone from the anterior approach was harvested started with a saw, and then a chisel and mallet were used. After 6 months removal of the screws of synthesis (1 fractured is left in place). Insertion of endosseous implants After 3 months loading with mixed prosthesis (bar + overdenture) with locator. Several Authors have reported pain on walking, weakness of the abdominal wall, frank herniation, and disturbances of gait. A few other approaches have been suggested to reduce impairments at the donor site such as taking only the inner cortex, which will reduce the amount of bone available and its implantability. Others have suggested leaving the iliac crest and harvesting the underlying bone. It is concluded that in treatment combining an onlay graft and simultaneous implant placement in the extremely resorbed mandible, considerable graft resorption must be anticipated. [ABSTRACT FROM AUTHOR]

Patients and methods A longitudinal study was carried out in 255 children from 10 centres in nine developing countries over 5 years to assess the musculoskeletal outcome of children on episodic factor replacement. Outcome was documented by assessment of the annual joint bleeding rate ( AJBR), WFH clinical and Pettersson radiological joint scores as well as the FISH score for activities. Of the 203 patients for whom data was available at the end of 5 years, 164 who had received only episodic treatment are included in this report. Results The median age at the beginning of the study was 10 years ( IQR 7-12). The median clotting factor concentrate ( CFC) usage was 662 IU kg−1 year−1 ( IQ range: 280-1437). The median AJBR was 10 ( IQ range: 5-17). The median AJBR was higher in the older children with the median being 5 for the 5 year old child, while it was 9 for the 10 year old and 11 for children older than 15. Given the episodic nature of the replacement therapy, those with a higher AJBR used significantly greater annual CFC doses ( P < 0.001); The median change in WFH clinical score and Pettersson radiological score over the 5 years was 0.4/year for each, while the FISH deteriorated at a rate of 0.2/year with poor correlation of these changes with CFC dose. WFH and FISH scores were significantly worse in those with an AJBR of >3 per year ( P = 0.001). The change in the Pettersson score was significantly more in those with an AJBR of >5 per year ( P = 0.020). Significant changes in FISH scores were only noted after 10 years of age. Conclusion Episodic CFC replacement over a large range of doses does not alter the natural course of bleeding in haemophilia or the musculoskeletal deterioration and should not be recommended as a long term option for treatment. Prophylaxis is the only way to preserve musculoskeletal function in haemophilia. [ABSTRACT FROM AUTHOR]

The ability to predict upcoming structured events based on long-term knowledge and contextual priors is a fundamental principle of human cognition. Tonal music triggers predictive processes based on structural properties of harmony, i.e., regularities defining the arrangement of chords into well-formed musical sequences. While the neural architecture of structure-based predictions during music perception is well described, little is known about the neural networks for analogous predictions in musical actions and how they relate to auditory perception. To fill this gap, expert pianists were presented with harmonically congruent or incongruent chord progressions, either as musical actions (photos of a hand playing chords) that they were required to watch and imitate without sound, or in an auditory format that they listened to without playing. By combining task-based functional magnetic resonance imaging (fMRI) with functional connectivity at rest, we identified distinct sub-regions in right inferior frontal gyrus (rIFG) interconnected with parietal and temporal areas for processing action and audio sequences, respectively. We argue that the differential contribution of parietal and temporal areas is tied to motoric and auditory long-term representations of harmonic regularities that dynamically interact with computations in rIFG. Parsing of the structural dependencies in rIFG is co-determined by both stimulus- or task-demands. In line with contemporary models of prefrontal cortex organization and dual stream models of visual-spatial and auditory processing, we show that the processing of musical harmony is a network capacity with dissociated dorsal and ventral motor and auditory circuits, which both provide the infrastructure for predictive mechanisms optimising action and perception performance. [ABSTRACT FROM AUTHOR]

Background and Aim: Despite the usefulness of bowel US in intestinal diseases, barium enteroclysis (BE) remains the gold standard technique for assessing patients with CD involving the ileum/jejunum. A novel [...]

The phenology of two local peach genotypes was studied to verify whether peaches can be produced in the Tanzanian uplands. Observations were conducted on trees of one early- and one late-ripening peach genotype in 2010 and 2011. Temperature trends were reconstructed and three chilling estimation models were tested. The two peach genotypes differed for timing of flower and leaf bud-break. Common symptoms of insufficient chilling (presence of numerous stages at a specific date and about 20% of undeveloped flower buds) were observed in the late genotype. Both Utah and Dynamic models indicated low chilling accumulation, lower than the Mean Temperature model in most cases. This is inconsistent with the actual phenology, suggesting that (1) both models show some limitations under our conditions, (2) the two genotypes partly adapted to the local climate, and (3) mechanisms other than chilling (seasonal rainfall fluctuations) play a role in rest control. [ABSTRACT FROM PUBLISHER]

Background: Multiple lines of evidence support that the Hedgehog (Hh) signalling has a role in the maintenance and progression of different human cancers. Therefore, inhibition of the Hh pathway represents a valid anticancer therapeutic approach for renal cell carcinoma (RCC) patients. NVP-LDE225 is a Smoothened (Smo) antagonist that induces dose-related inhibition of Hh and Smo-dependent tumour growth.Methods: We assayed the effects of NVP-LDE225 alone or in combination with everolimus or sunitinib on the growth and invasion of human RCC models both in vitro and in vivo. To this aim, we used a panel of human RCC models, comprising cells with acquired resistance to sunitinib - a multiple tyrosine kinase inhibitor approved as a first-line treatment for RCC. Results: NVP-LDE225 cooperated with either everolimus or sunitinib to inhibit proliferation, migration, and invasion of RCC cells even in sunitinib-resistant (SuR) cells. Some major transducers involved in tumour cell motility, including paxillin, were also efficiently inhibited by the combination therapy, as demonstrated by western blot and confocal microscopy assays. Moreover, these combined treatments inhibited tumour growth and increased animal survival in nude mice xenografted with SuR RCC cells. Finally, lung micrometastasis formation was reduced when mice were treated with NVP-LDE225 plus everolimus or sunitinib, as evidenced by artificial metastatic assays. Conclusions: Hedgehog inhibition by NVP-LDE225 plus sunitinib or everolimus bolsters antitumour activity by interfering with tumour growth and metastatic spread, even in SuR cells. Thus, this new evidence puts forward a new promising therapeutic approach for RCC patients. [ABSTRACT FROM AUTHOR]

Background:Cetuximab is the only targeted agent approved for the treatment of head and neck squamous cell carcinomas (HNSCC), but low response rates and disease progression are frequently reported. As the phosphoinositide 3-kinase (PI3K) and the mammalian target of rapamycin (mTOR) pathways have an important role in the pathogenesis of HNSCC, we investigated their involvement in cetuximab resistance.Methods:Different human squamous cancer cell lines sensitive or resistant to cetuximab were tested for the dual PI3K/mTOR inhibitor PF-05212384 (PKI-587), alone and in combination, both in vitro and in vivo.Results:Treatment with PKI-587 enhances sensitivity to cetuximab in vitro, even in the condition of epidermal growth factor receptor (EGFR) resistance. The combination of the two drugs inhibits cells survival, impairs the activation of signalling pathways and induces apoptosis. Interestingly, although significant inhibition of proliferation is observed in all cell lines treated with PKI-587 in combination with cetuximab, activation of apoptosis is evident in sensitive but not in resistant cell lines, in which autophagy is pre-eminent. In nude mice xenografted with resistant Kyse30 cells, the combined treatment significantly reduces tumour growth and prolongs mice survival.Conclusions:Phosphoinositide 3-kinase/mammalian target of rapamycin inhibition has an important role in the rescue of cetuximab resistance. Different mechanisms of cell death are induced by combined treatment depending on basal anti-EGFR responsiveness. [ABSTRACT FROM AUTHOR]

Highlights: [•] All low-vigor rootstocks reduced vegetative growth compared to GF677. [•] Trees on IS5/29 offered best compromise of growth reduction, fruit size and yields. [•] Trees on IS5/23 exhibited greatest growth reductions and yield efficiency. [•] Postharvest water deficit induced greatest yield reductions in trees on GF677. [•] Trees on Castore and Polluce showed lowest sensitivity to postharvest water deficit. [ABSTRACT FROM AUTHOR]

Background:We aimed to study key signalling proteins involved in angiogenesis and proliferation on the response to inhibitors of tyrosine kinases and mammalian target of rapamycin in first- and in second-line treatment of renal cell carcinoma (RCC).Methods:In a panel of human RCC tumours, in vitro and in nude mice, we evaluated the effect of sunitinib, sorafenib and everolimus, alone and in sequence, on tumour growth and expression of signalling proteins involved in proliferation and resistance to treatment.Results:We demonstrated that, as single agents, sunitinib, sorafenib and everolimus share similar activity in inhibiting cell proliferation, signal transduction and vascular endothelial growth factor (VEGF) secretion in different RCC models, both in vitro and in tumour xenografts. Pre-treatment with sunitinib reduced the response to subsequent sunitinib and sorafenib but not to everolimus. Inability by sunitinib to persistently inhibit HIF-1, VEGF and pMAPK anticipated treatment resistance in xenografted tumours. After first-line sunitinib, second-line treatment with everolimus was more effective than either sorafenib or rechallenge with sunitinib in interfering with signalling proteins, VEGF and interleukin-8, translating into a significant advantage in tumour growth inhibition and mice survival.Conclusion:We demonstrated that a panel of angiogenic and signalling proteins can correlate with the onset of resistance to sunitinib and the activity of everolimus in second line. [ABSTRACT FROM AUTHOR]

Increasing irrigation efficiency is a major goal for fruit production in dry Mediterranean environments. The present study was conducted in three consecutive years (2007–09) under typical Mediterranean conditions and tested the effect of partial rootzone drying (PRD) on yield and fruit quality of two apple cultivars: Gala, with fruit maturing in summer and Fuji, with fruit maturing in autumn. Three irrigation treatments were imposed: conventional irrigation (CI), PRD (0·50 of CI water on one side of the rootzone, which was alternated periodically) and continuous deficit irrigation (DI, 0·50 of CI water on both sides of the rootzone). During the 2008 and 2009 irrigation seasons, DI reduced tree water status, and to some extent soil moisture, compared with CI and PRD. In all the years and both cultivars, DI reduced crop load by 11 and 5% over CI and PRD, respectively. In cvar Fuji, DI reduced production per tree by 9% and yield efficiency by 16% compared with CI. In all years for cvar Gala and in 2 of the 3 years for cvar Fuji, PRD and DI increased fruit soluble solid content by 5–6%, whereas PRD improved peel colour only in cvar Fuji and in 2 of the 3 years. In cvar Gala, DI fruit showed 27% more sorbitol and 55% more sucrose than PRD fruit. In both cultivars, PRD determined greater marketable yield and profit than DI. Irrigation water productivity (IWP) was increased by both PRD and DI, and in Fuji, PRD induced 18% greater IWP than DI. The different responses of the two cultivars to irrigation treatments can be attributed to differences in canopy size, crop load and mostly to the different timing of fruit growth. In particular, undergoing fast fruit growth during the irrigation period seems to induce permanent yield reductions in DI (but not PRD) trees of cvar Fuji, whereas water deficit during late fruit growth and lower crop load may have cancelled the negative effect of DI in the smaller trees of cvar Gala. [ABSTRACT FROM PUBLISHER]

Background:Targeting the mammalian target of rapamycin by everolimus is a successful approach for renal cell carcinoma (RCC) therapy. The Toll-like receptor 9 agonist immune modulatory oligonucleotide (IMO) exhibits direct antitumour and antiangiogenic activity and cooperates with both epidermal growth factor receptor (EGFR) and vascular endothelial growth factor (VEGF) inhibitors.Methods:We tested the combination of IMO and everolimus on models of human RCC with different Von-Hippel Lindau (VHL) gene status, both in vitro and in nude mice. We studied their direct antiangiogenic effects on human umbilical vein endothelial cells.Results:Both IMO and everolimus inhibited in vitro growth and survival of RCC cell lines, and their combination produced a synergistic inhibitory effect. Moreover, everolimus plus IMO interfered with EGFR-dependent signaling and reduced VEGF secretion in both VHL wild-type and mutant cells. In RCC tumour xenografts, IMO plus everolimus caused a potent and long-lasting cooperative antitumour activity, with reduction of tumour growth, prolongation of mice survival and inhibition of signal transduction. Furthermore, IMO and everolimus impaired the main endothelial cell functions.Conclusion:A combined treatment with everolimus and IMO is effective in VHL wild-type and mutant models of RCC by interfering with tumour growth and angiogenesis, thus representing a potentially effective, rationale-based combination to be translated in the clinical setting. [ABSTRACT FROM AUTHOR]

Background:Anti-epidermal growth factor receptor (EGFR) monoclonal antibodies are restricted to KRAS wild-type (WT) metastatic colorectal cancers (mCRCs), usually identified by direct sequencing, that may yield false negative results because of genetic heterogeneity within the tumour. We evaluated the efficiency of high-resolution melting analysis (HRMA) in identifying KRAS-mutant (MUT) tumours.Methods:We considered 50 mCRC patients scored as KRAS-WT by direct sequencing and treated with cetuximab-containing chemotherapy, and tested the correlations between HRMA findings and response rate (RR), progression-free (PFS) and overall survival (OS).Results:Aberrant melting curves were detected in four (8%) cases; gene cloning confirmed these mutations. Response rate (RR) of HRMA KRAS-WT patients was 28.3%. There was no response in HRMA KRAS-MUT patients. Disease control rate (responsive plus stable disease) was 58.7% in HRMA KRAS-WT patients and 25% in HRMA KRAS-MUT patients. There was no correlation between HRMA KRAS status and RR (P=0.287) or disease control (P=0.219). Median PFS (4.8 vs 2.3 months; hazard ratio (HR)=0.29, P=0.02) and OS (11.0 vs 2.7 months; HR=0.11, P=0.03) were significantly longer for the HRMA KRAS-WT than for HRMA KRAS-MUT patients.Conclusions:High-resolution melting analysis identified 8% more KRAS-MUT patients not responding to cetuximab-containing regimens, suggesting that HRMA may be more effective than direct sequencing in selecting patients for anti-EGFR antibodies. [ABSTRACT FROM AUTHOR]

The effects of partial rootzone drying (PRD) and rootstock vigour on dry matter accumulation and partitioning among leaves, shoots, fruits, frame and roots of apple trees (Malus domestica Borkh. cvar Pink Lady) were investigated in 2005 near Caltavuturo, in Sicily. In a first field trial, trees on MM.106 rootstock were subjected to: conventional irrigation (CI), maintaining soil moisture above 0·80 of field capacity; PRD irrigation, where alternating sides of the rootzone received 0·50 of the CI irrigation water; and continuous deficit irrigation (DI), where 0·50 of the CI water was equally applied to both sides of the rootzone. In a second trial, trees on M.9 or MM.106 were subjected to CI and PRD irrigation. In trial 1, dry matter accumulation was markedly reduced by DI irrigation and to a lesser extent by PRD; PRD trees partitioned 20% less to leaves, 31% less to fruits and 24% more to woody components than CI trees; DI trees partitioned 14% less to current shoots and 18% more to fruits than CI and had the highest fruit:leaf ratio. In trial 2, there was no interaction between rootstock and irrigation treatments. MM.106 induced greater leaf, shoot, frame and root dry weights (DWs) than M.9, resulting in more vegetative growth and larger trees. PRD reduced leaf, shoot, frame and fruit DWs, while root DWs were similar to CI, and thus PRD trees were 18% smaller than CI trees. Neither rootstock nor irrigation affected dry matter partitioning among organs or root:canopy ratio, whereas PRD trees or trees on MM.106 showed better water use efficiency than CI and M.9, respectively. The results show that PRD trees did not activate drought tolerance strategies in terms of dry matter allocation that could improve acquisition of water resources, regardless of rootstock. PRD irrigation increased above-ground dry matter partitioning towards woody components at the expense of leaves and fruits. [ABSTRACT FROM PUBLISHER]

Background: Overexpression of ErbB2 receptor in breast cancer is associated with disease progression and poor prognosis. Trastuzumab, the only humanised anti-ErbB2 antibody currently used in breast cancer, has proven to be effective; however, a relevant problem for clinical practice is that a high fraction of breast cancer patients shows primary or acquired resistance to trastuzumab treatment.Methods: We tested on trastuzumab-resistant cells two novel human anti-tumour immunoconjugates engineered in our laboratory by fusion of a human anti-ErbB2 scFv, termed Erbicin, with either a human RNase or the Fc region of a human IgG1. Both Erbicin-derived immunoagents (EDIAs) are selectively cytotoxic for ErbB2-positive cancer cells in vitro and vivo, target an ErbB2 epitope different from that recognised by trastuzumab and do not show cardiotoxic effects.Results: We report that EDIAs are active also on trastuzumab-resistant tumour cells both in vitro and in vivo, most likely because of the different epitope recognised, as EDIAs, unlike trastuzumab, were found to be able to inhibit the signalling pathway downstream of ErbB2.Conclusion: These results suggest that EDIAs are immunoagents that could not only fulfil the therapeutic need of patients ineligible to trastuzumab treatment due to cardiac dysfunction but also prove to be useful for breast cancer patients unresponsive to trastuzumab treatment. [ABSTRACT FROM AUTHOR]

We investigated the antitumour effect and ability to overcome the resistance to anti-EGFR drugs of enzastaurin, an inhibitor of VEGFR-dependent PKCbeta signalling. Enzastaurin was evaluated alone and in combination with the EGFR inhibitor gefitinib, on growth and signalling protein expression in human cancer cells sensitive and resistant to anti-EGFR drugs, both in vitro and in nude mice. We demonstrated the marked inhibitory activity of enzastaurin against GEO colon and PC3 prostate cancer cells and their gefitinib-resistant counterparts GEO-GR and PC3-GR, accompanied by inhibition of pAkt and its effector pp70S6K, pGSK3beta and VEGF expression and secretion. Moreover, enzastaurin showed a cooperative effect with gefitinib in parental and in gefitinib-resistant cells. Remarkably, these results were confirmed in vivo, where enzastaurin showed antitumour activity and cooperativity with gefitinib in mice grafted with GEO and GEO-GR tumours, incrementing their median survival and inhibiting the aforesaid protein expression and secretion in tumour specimens. In conclusion, enzastaurin by interfering with signalling proteins implicated in EGFR drug resistance markedly cooperates with gefitinib in sensitive and gefitinib-resistant tumours, thus overcoming and reverting such resistance and providing a rational basis for its development in patients resistant to anti-EGFR drugs. [ABSTRACT FROM AUTHOR]

Inhibition of a single transduction pathway is often inefficient due to activation of alternative signalling. The mammalian target of rapamycin (mTOR) is a key intracellular kinase integrating proliferation, survival and angiogenic pathways and has been implicated in the resistance to EGFR inhibitors. Thus, mTOR blockade is pursued to interfere at multiple levels with tumour growth. We used everolimus (RAD001) to inhibit mTOR, alone or in combination with anti-EGFR drugs gefitinib or cetuximab, on human cancer cell lines sensitive and resistant to EGFR inhibitors, both in vitro and in vivo. We demonstrated that everolimus is active against EGFR-resistant cancer cell lines and partially restores the ability of EGFR inhibitors to inhibit growth and survival. Everolimus reduces the expression of EGFR-related signalling effectors and VEGF production, inhibiting proliferation and capillary tube formation of endothelial cells, both alone and in combination with gefitinib. Finally, combination of everolimus and gefitinib inhibits growth of GEO and GEO-GR (gefitinib resistant) colon cancer xenografts, activation of signalling proteins and VEGF secretion. Targeting mTOR pathway with everolimus overcomes resistance to EGFR inhibitors and produces a cooperative effect with EGFR inhibitors, providing a valid therapeutic strategy to be tested in a clinical setting. [ABSTRACT FROM AUTHOR]

Transgenic mannitol-producing (+mtlD) and wild-type (-mtlD) tobacco plants were exposed to water deficit, varying light intensities, low temperatures, and paraquat applications to test whether mannitol was involved in protection against abiotic stresses. In the water deficit experiment, -milD and +milD plants were fully irrigated [100% evapotranspiration (ET)] or received 25% ET for 40 d. Water deficit reduced the relative water content (RWC) of both types of plant, starting on day 22, and the total stem length (TSL) of -mtlD 25% ET plants after 11 d, whereas the TSL of +mtlD 25% ET plants was reduced only after 34 d. After 30 d of water deficit, a higher percentage of mature foliage was retained by +mitD 25% ET plants compared to -mitD 25% ET plants. The mannitol-1-phosphate dehydrogenase activity of +mtlD plants was not affected by water deficit. The photosynthetic rates of +mtlD and -mtlD plants were measured at PPFD levels ranging from 0 to >2,000 jimol m-2 s-1. No differences in quantum yield, saturation and compensation points, or dark respiration were observed between the +mtlD and -mtlD plants. Exposing the leaves of +mtlD and -mtlD plants to 0°C for 24 h caused significant injury to cell membranes and was similar in both types of plant. The application of 0.2 mM paraquat onto expanding -mtlD leaves produced a higher percentage of necrotic leaf area (4.3%) compared to +mtlD leaves (0.48%). The amount of mannitol produced by +mtlD plants could not provide significant osmotic protection, or increases in photosynthesis, whereas it may provide a specific system to protect cells from free radical-induced damage. [ABSTRACT FROM AUTHOR]

In this work quality of tree ripe and commercial ripe 'Fairtime' peach fruit was evaluated during fruit maturation and storage. Quality parameters and volatile fraction were monitored at intervals of 7-15 days from pit hardening until 10 days after commercial harvest and after 7, 17 and 24 days of refrigeration. In fruit on the tree, weight increased quadratically, diameter and peel color increased linearly, whereas flesh firmness decreased linearly. Soluble solids (SS) reached maximum levels at commercial harvest, whereas acidity started declining after commercial harvest. In the peel, esters and alcohols showed opposite trends. In the flesh, alcohols decreased quadratically and disappeared in tree ripe fruit. In refrigerated fruit, there were no significant weight changes, flesh firmness decreased linearly, SS reached a minimum around the 10th day, and acidity decreased quadratically. A three day harvest delay followed by two weeks of refrigeration may represent a chance to further extend marketing of optimum flavor 'Fairtime' peaches into late fall. [ABSTRACT FROM AUTHOR]

The aim of the study was to assess the toxicity and the clinical activity of biweekly oxaliplatin in combination with infusional 5-fluorouracil (5-FU) and folinic acid (FA) administered every 2 weeks (FOLFOX-4 regimen) in patients with advanced gastric cancer (AGC). A total of 61 previously untreated AGC patients were treated with oxaliplatin 85?mg?m-2 on day 1, FA 200?mg?m-2 as a 2?h infusion followed by bolus 5-FU 400?mg?m-2 and a 22?h infusion of 5-FU 600?mg?m-2, repeated for 2 consecutive days every 2 weeks. All patients were assessable for toxicity and response to treatment. Four (7%) complete responses and 19 partial responses were observed (overall response rate, 38%). Stable disease was observed in 22 (36%) patients, with progressive disease in the other six (10%) patients. Median time to progression (TTP) and median overall survival (OS) were 7.1 and 11.2 months, respectively. National Cancer Institute Common Toxicity Criteria grade 3 and 4 haematologic toxicities were neutropenia, anaemia and thrombocytopenia in 36, 10 and 5%of the patients, respectively. Grade 3 peripheral neuropathy was recorded in three (5%) patients. FOLFOX-4 is an active and well-tolerated chemotherapy. Response rate (RR), TTP and OS were comparable with those of other oxaliplatin-based regimens, suggesting a role for this combination in gastric cancer.British Journal of Cancer (2005) 92, 1644-1649. doi:10.1038/sj.bjc.6602573 www.bjcancer.com Published online 26 April 2005 [ABSTRACT FROM AUTHOR]

The effects of M.9 and MM.106 rootstocks and in-row spacing (0.4, 0.7, and 1 m) on the vegetative behaviour of three-year-old apple (Malus domestica Borkh) trees were studied. Analysis of digital images was used to estimate canopy and root growth and conformation (shape and size), whereas dry-matter distribution was used to determine partitioning to various plant parts. Trees on less vigorous M.9 rootstocks showed reduced stem and root growth as they produced fewer and/or shorter shoots and fewer and/or shorter and thinner roots. Canopy spread area (CSA) and volume were similar for trees on both rootstocks and differences in stem length density (stem length per unit canopy volume; SLD) compensated for the difference in stem growth. For M.9 roots, the decrease in growth was reflected in the reduction in root spread area (RSA), which was not compensated for by the increase in root length density (root length per unit RSA; RLD). Trees on M.9 allocated more dry matter to above-ground structures, whereas trees on MM.106 partitioned more to roots. Leaf to root surface area ratio (L:R) was also greater for trees on M.9. Stems of trees grown 0.4 m apart weighed less because they were thinner, whereas the same trees produced fewer and/or shorter, but thicker roots, which resulted in similar root dry weights for trees at all spacings. Canopy height increased with spacing for trees on M.9, whereas it was negatively related to spacing for MM.106. CSA was rounder at the wider spacings and exceeded the allotted soil surface at the closest one. For three year old apple trees, optimum in-row spacing (no shoot overlap and full coverage of allotted space) was about 0.7 m for M.9 and 0.8 m for MM.106. RSA was also rounder at the larger spacings, but never filled the allotted space. Dry-matter distribution was significantly influenced by spacing, and root to shoot ratio (R:S) was highest at the widest spacing. The vegetative behaviour of young apple trees was influenced by both rootstock vigour and tree spacing. Also, trees on the M.9 rootstock reflected greater ability to compete for available resources and adapt to space confinement and, therefore, may represent a better option for cultivation of apple in the settings and at the planting densities considered. [ABSTRACT FROM AUTHOR]

Prunus ferganensis (Kost. & Riab) Kov. & Kost, a close relative of cultivated peach (Prunus persica (L.) Batsch.), is native to arid regions of central Asia. A distinguishing feature of P. ferganensis is its prominent, elongated, unbranched pattern of leaf venation. To determine whether the long-vein trait could be used as a marker in breeding for drought tolerance, we investigated the association between this trait and the leaf morphological and physiological parameters related to drought response in P. ferganensis, P. persica and two interspecific hybrids, one with the long-vein trait (BY94P7585) and one without (BY94P7589). The four genotypes were grafted onto “Guardian” peach rootstock and half of the plants were assigned to a drought treatment in which irrigation was limited to 25–50% of the evapotranspiration (ET) rate measured in the remaining well-watered plants, which were irrigated to runoff daily. The drought treatment reduced photosynthesis and leaf conductance by 49–83% and reduced total leaf area per plant by 17–24%, but generally did not affect mid-morning leaf water potential. Leaf gas exchange did not differ among genotypes in either treatment. Sorbitol accumulated in mature leaves in response to drought, but neither its amount nor its metabolism varied systematically with climatic adaptation among genotypes. Accumulation of transport sugars was highest in P. ferganensis, indicating that growth reduction may represent an important strategy for coping with drought in this species. Prunus ferganensis and the hybrids had higher ET than P. persica, and seemed to use water opportunistically, maintaining high gas exchange rates and consequently high ET when water was available, and avoiding low water potentials through stomatal closure as soil water declined. Leaf size (cm2 leaf−1) and specific leaf area (cm2 g−1 dry mass) were lower in P. ferganensis and the hybrids than in P. persica. We conclude that the long-vein trait is not a reliable marker for drought tolerance, but leaf traits of P. ferganensis such as size and specific leaf area may be useful in P. persica breeding programs targeting drought tolerance. [ABSTRACT FROM PUBLISHER]