Carbon isotope discrimination and water use efficiency in interspecific Prunus hybrids subjected to drought stress

In C3 plants, carbon isotope composition (δ13C) is influenced by isotopic effects during diffusion from the atmosphere to the chloroplasts and carboxylation reactions. This work aimed to demonstrate if δ13C of leaf soluble carbohydrates (δ13Cleaves) and of dry matter from new-growth shoots (δ13Cshoots) of Prunus plants subjected to a period of water deficit was related to water use efficiency (WUE). For this purpose, three interspecific Prunus hybrids rootstocks (6–5, 7-7 and G × N) were gradually subjected to drought and then rewatered. Soil water content (SWC) decreased from 26.1 to 9.4% after 70 days of water shortage, when plants reached values of predawn leaf water potential (LWP) ranging from −3.12 to −4.00 MPa. Gas exchange, particularly net photosynthetic and transpiration rates, differed among the three hybrids, leading to different values of WUE. After 70 days of drought, a significant δ13C increase of 5.86, 4.28 and 4.99‰ was observed in 6–5, 7-7 and G × N, respectively. Significant correlations between δ13C and other parameters (substomatal CO2/atmospheric CO2 ratio, stomatal conductance and stem water potential) were found in all hybrids. The rewatering phase caused a recovery of the physiological status of the plants. The isotope composition of δ13Cshoots was correlated with the average WUE measured during the whole experiment. δ13Cleaves and δ13Cshoots were positively related (r = 0.87; p < 0.001). The isotopic signature was a reliable screening tool to identify Prunus genotypes tolerant to drought stress. The results suggest the possibility of using δ13C as an integrated indicator of level of drought stress in plants subjected to prolonged stress conditions

A regional audit system for stillbirth: A way to better understand the phenomenon

Background: Implementation of high-quality national audits for perinatal mortality are needed to improve the registration of all perinatal deaths and the identification of the causes of death. This study aims to evaluate the implementation of a Regional Audit System for Stillbirth in Emilia-Romagna Region, Italy. Methods: For each stillbirth ( 65 22 weeks of gestation, 65 500 g) occurred between January 1, 2014 to December 1, 2016 (n = 332), the same diagnostic workup was performed and a clinical record with data about mother and stillborn was completed. Every case was discussed in a multidisciplinary local audit to assess both the cause of death (ReCoDe classification) and the quality of care. Data were reviewed by the Regional Audit Group. Stillbirth rates, causes of death and the quality of care were established for each case. Results: Total stillbirth rate was 3.09 per 1000 births (332/107,528). Late stillbirth rate was 2.3 per 1000 (251/107,087). Sixteen stillbirths were not registered by the Regional Birth Register. The most prevalent cause of death was placental disorder (33.3%), followed by fetal (17.6%), cord (14.2%) and maternal disorders (7.6%). Unexplained cases were 14%. Compared to local audits, the regional group attributed different causes of death in 17% of cases. At multivariate analysis, infections were associated with early stillbirths (OR 3.38, CI95% 1.62-7.03) and intrapartum cases (OR 6.64, CI95% 2.61-17.02). Placental disorders were related to growth restriction (OR 1.89, CI95% 1.06-3.36) and were more frequent before term (OR 1.86, CI95% 1.11-3.15). Stillbirths judged possibly/probably preventable with a different management (10.9%) occurred more frequently in non-Italian women and were mainly related to maternal disorders (OR 6.64, CI95% 2.61-17.02). Conclusions: Regional Audit System for Stillbirth improves the registration of stillbirth and allows to define the causes of death. Moreover, sub-optimal care was recognized, allowing to identify populations which could benefit from preventive measures

Sedazione nello studio odontoiatrico: Questi i consigli clinici e quanto prevede la normativa

Odontoiatria3

Influence of water deficit and rewatering on the components of the ascorbate-glutathione cycle in four interspecific Prunus hybrids

The activities of ascorbate peroxidase (APX, EC 1.11.1.11), monodehydroascorbate reductase (MDHAR, EC 1.6.5.4), dehydroascorbate reductase (DHAR, EC 1.8.5.1) and glutathione reductase (GR, EC 1.6.4.2), as well as the levels of ascorbate pool, glutathione pool and H2O2 were studied in plants of four interspecific Prunus hybrids subjected to water deficit and shade conditions. After 70 days of water shortage, plants were subjected to a rewatering treatment. During water recovery, leaves fully exposed to sunlight and leaves in shade conditions of about 30% of environmental irradiance were sampled. After 70 days without irrigation, mean pre-dawn leaf water potential of all the hybrids fell from 0.34 to 3.30 MPa and marked decreases in net photosynthesis and transpiration occurred. The activities of APX, MDHAR, DHAR and GR increased in relation to the severity of drought stress in all the clones studied. Generally, APX, MDHAR, DHAR and GR were down-regulated during the rewatering phase and their activities decreased faster in shaded leaves than in non-shaded leaves. The levels of total ascorbate, total glutathione and H2O2 were directly related to the increase of drought stress and subsequently decreased during rewatering. This response could limit cellular damage caused by active oxygen species during periods of water deficit. The ability of Prunus hybrids to regulate the enzymatic antioxidant system during different water and irradiance conditions might be an important attribute linked to drought tolerance

Effetti della micorrizazione sulla qualità di piante di pesco: i risultati del progetto SITINPLANT

INPRES

Preliminary results on the behaviour of two micropropagated and grafted apricot cultivars

The responses of ‘Flopria’ apricot to the propagation techniques of micropropagation (M) and graft (G) were compared through the assessment of some vegetative and reproductive traits. Both the M and G trees were planted (5×3 m distance) in 2011 at a private farm in southern Italy and trained to open vase. At 2 and 4 years after planting, the trunk diameter, tree height, number of floral buds, flowers, fruit-set and the presence of spiny spurs were recorded. At 2015 harvest, fruit size, °Brix and fruit firmness were determined. Trunk diameter and fruit quality traits did not differ between treatments, while the numbers of floral buds, flowers and fruit-set of M trees were on average ~65% of those of G trees. Tree height and the presence of spiny spurs on basal branches were higher in M trees. The paper discusses the overall higher presence of juvenile traits in M trees compared to G trees

LIFE AgroClimaWater project: environmental impact and water use of sustainable fruit orchards in Mediterranean area

Climate change is gradually affecting regional and global food production. Warming temperatures and intensity of extreme weather events may lead to significant reductions in crop yields. The LIFE AgroClimaWater project provides adaptation management strategies to increase water productivity in fruit orchards, reducing pollution and resource use. The increase of water use efficiency was achieved through a sustainable irrigation strategy based on the integration of the daily soil water balance with soil moisture measurements (from 0 to 90 cm depth). The monitoring of the soil profile contributes to optimize irrigation volumes, avoiding nutrient loss and percolation in the deep layers. The experimental sites of fruit orchards have been divided into two plots: one managed with sustainable practices (no-tillage, supply of organic fertilisers, mulching of pruning residues, cover crops and guided irrigation, controlled water stress) and another one conventionally managed (weeding, distribution of mineral fertilizers, empirical irrigation). Effectiveness of good agricultural practices (GAPs) applied in sustainable plots was assessed by performance indicators as Water Use Efficiency (WUE), Water Footprint (WF), Nutrient Use Efficiency (NUE) that were compared to conventionally managed plots. Results revealed that the sustainable irrigation strategy leads to a more than 30.0% decrease in the WF, a more than 20.0% increase in the WUE and a nitrogen use efficiency (NUEN) greater than 1.5 times in the sustainable orchards compared to that conventional ones. Moreover, the sustainable management has a beneficial effect on natural resources (soil and water) conservation and restoration, implementing the water productivity of the agro-ecosystem and highlighting the mitigation role of agro-ecosystems