Transpiration and calcium accumulation in apricot fruit

The seasonal variation of transpiration rate and accumulation of calcium (Ca) in fruit of apricot (Prunus armeniaca L.) are presented. Midday transpiration rate (open system ADC-LCA4) was higher just after fruit-set peaking at about 0.5 mmol m-2 s-1; thereafter it declined and reached the lowest value three weeks later. In parallel, Ca was linearly accumulated within the early four weeks of fruit development reaching 80% of the final content. Afterwards it slowly increased and reached about 6 mg per fruit at harvest time. Results suggest that transpiration decline can be held to account for the early cessation of Ca import into the fruit. Opportunities for field manipulation to increase fruit Ca content are discussed

Sustainable apricot orchard management to improve soil fertility and water use efficiency

This 4-year on-farm study reports the effects of different agricultural practices on yield and carbon input in an apricot orchard grown in Mediterranean area. Groups of plants under local orchard management (LOM) practices (i.e., soil tillage, removing of pruning residues, mineral fertilisers) were compared with plots under sustainable orchard management (SOM) actions (i.e., cover crop, no-tillage, compost application, mulching of pruning residues). In the SOM blocks, fertilization was based on plant demand and soil availability and irrigation volumes were calculated on the evapotranspiration values basis, while in the LOM plots fertilization and irrigation were empirically managed. Results show that yield was enhanced by 28% by SOM. In comparison with LOM plots, changed practices increased the amount of N, P, K annually incorporated into soil thus increasing their reservoir in the soil. The study demonstrates that appropriate crop management can increase the mean annual carbon soil inputs from about 1.5 t ha-1 to 9.0 t ha-1 per year

Integration of the regulated deficit irrigation strategy in a sustainable orchard management system

Irrigation in arid regions requires special attention to optimize the management of all components of the orchard system in order to increase water use efficiency and reduce environmental impacts (e.g. soil salinization, degradation of ground and surface waters). This six-year study reports the comparison of some orchard practices (soil and irrigation management, plant nutrition) routinely adopted by local farmers (conventional, C) with those interventions having the potential to save water and maximize water use efficiency in a peach orchard and therefore defined as sustainable (S). Due to the relative approach (C versus S) used in this study, classical statistical comparison of results could not be made. The S system included the application of regulated deficit irrigation (RDI) with specific crop coefficients to calculate the plant water requirement. The S system on average saved 1450 m3 ha-1 of water per year without affecting yield or fruit quality. The concept of economic water productivity (EWP) is discussed. We conclude that addressing some practices currently adopted by farmers could increase sustainability of irrigation and enhance (EWP) in peach tree orchards

Development of guide lines for the calculation of carbon footprint of peaches and apricots produced in Metapontino area (Basilicata): the project IQuaSoPO

The present study is conducted in the framework of the project IQuaSoPO. financed by the regional funds for rural development of Basilicata Region (Italy). It is a three year project which aims to transfer good sustainable practices to local fruit producers. One of the main expected results of the project is to develop guidelines for the calculation of carbon footprint of peaches and apricots, in a life cycle perspective, referred to the productive and geographical specificities of Metapontino area. These guidelines will be used by the local producer to easily assess and communicate the environmental sustainability of their products, which, in this way, will gain added value on the market. Three experimental fields for the production of peaches and apricots in the area of Metaponto are involved in the transfer of knowledge process, about carbon management and water management sustainable practices, which can influence the entity of GHG emissions, by favouring the accumulation of important amounts of carbon and nitrogen in soil and in the perennial parts of peach tree (trunks, branches, roots). Examples of these sustainable management practices are: reduced tillage, soil grass cover, recycling of pruned materials within the field, deficit controlled irrigation, use of compost. In the framework of this study, the three pilot sites are used for inventory data collection, calculation of the carbon footprint, and development of the guidelines. The whole life cycle of the orchards is considered from the tree nursery stage (one or two years), through the establishment, the young, mature and decay stages, and the final destruction, for an average of 15 years. All the agricultural operations have been included in the accounting, in terms of energy consumption and machinery utilization: soil tillage, thinning, pruning, mulching, harvesting, fertilization, plant protection, irrigation, harvesting. Moreover, the life cycle of all the constituent materials of the orchard’s plant and cover structure has been considered (steel wire, cement and aluminum poles, cement blocks, irrigation pipes and water distribution final devices), as well as all the productive inputs’ life cycle (pests and fertilizers). Not just the production phase of the nitrogen fertilizers has been considered, but also the N2O emissions derived from their use. Two different functional units have been used: one kg of peaches/apricot produced and one hectare of cultivated field. The most innovative part of the present study consists in the integration of GHG fluxes occurring within soil-tree-atmosphere system, into the carbon footprint assessment: our aim is to estimate the soil carbon content change, in the considered time boundaries of the study (medium term perspective), related to soil respiration, plant growing, green and brown pruning decomposition, organic compost utilization, cover crop, through sampling activities at field, and using formulas from literature and different models recently emerging in the international scientific community. The guidelines for the carbon footprint calculation along the peach and apricots productive chain in Metapontino region are developed in accordance to the recently published standard ISO 14067; an innovative label for c-footprint communication could be introduced in order to improve the competitiveness of this products on national and international markets

Does dye infusion indicate xylem functionality in kiwifruit?

This study was undertaken to establish whether the rate of uptake of an aqueous solution by the fruitstalks of detached Actinidia deliciosa fruits (‘Hayward’) correlates with fruit xylem functionality assessed by dye infusion. Fruits were collected from the orchard, pre-dawn and 65 days after bloom. In the laboratory the fruitstalks were re-cut under water and their outsides lightly smeared with Vaseline before placing their cut ends in small, pre-weighed (W1) (mg) vials of dye solution. Fruits were allowed to take up dye solution for ~100 min (T) under uniform aerial conditions. Fruits were then sliced 1/5 way up from the stalk end and the fraction (F) (%) of stained bundles was determined. The residual dye solution was weighed (W2) (mg) and the solution uptake rate (U) (mg/min) determined per unit of fruit surface area (S) as U=(W1-W2)/(S×T). Analysis reveals that F is linearly related to U (R2 = 0.81). The suitability of the stain infusion technique for assessing xylem functionality is discussed