Search results for "DEFICIT"

Plant Response to Saline-Water Irrigation in a Sicilian Vineyard

2012

This chapter presents results of a 3-year field investigation in a vineyard located in Sicily (Mazara del Vallo, Trapani) within the framework of the Project “Evolution of cropping systems as affected by climate change” (CLIMESCO). Soil-plant responses to two saline irrigation waters were determined by measuring soil hydrological characteristics, soil salinity, crop transpiration and stomatal conductance in field plots of a Sicilian vineyard. The results proved that crop transpiration (T r) and stomatal conductance (G s) were significantly affected by soil salinity conditions, expressed by electrical conductivity of soil saturation extract (ECe). Significant reductions in T r and G s were f…

Sensory Processing in Children with Autism Spectrum Disorder and/or Attention Deficit Hyperactivity Disorder in the Home and Classroom Contexts.

2017

Children with neurodevelopmental disorders often show impairments in sensory processing (SP) and higher functions. The main objective of this study was to compare SP, praxis and social participation (SOC) in four groups of children: ASD Group (n = 21), ADHD Group (n = 21), ASD+ADHD Group (n = 21), and Comparison Group (n = 27). Participants were the parents and teachers of these children who were 5-8 years old (M = 6.32). They completed the Sensory Processing Measure (SPM) to evaluate the sensory profile, praxis and SOC of the children in both the home and classroom contexts. In the home context, the most affected was the ASD+ADHD group. The ADHD group obtained higher scores than the ASD gr…

RISPOSTA AL DEFICIT IDRICO CONTROLLATO DELL’OLIVO IN IMPIANTI SUPERINTENSIVI

2011

Responses of apple to partial root-zone drying. A review.

2013

Partial root-zone drying (PRD) is a relatively recent strategy aiming at substantial reduction of irrigation volume. It consists of the alternate irrigation of one portion of the root-zone with volumes reduced to about 40-50% of conventional water. PRD is based on the ability of roots in drying soil to produce hormonal signals, like abscissic acid (ABA), responsible for partial stomatal closure. In turn, partial stomatal closure would improve water use efficiency and increase fruit yield per unit of irrigation water. This technique has been tested on a number of fruit crops, including apple. In addition to climatic conditions, which mainly affect atmospheric water demand, soil properties an…

INFLUENCE OF BIOTIC AND ABIOTIC FACTORS ON QUALITY AND SECONDARY METABOLITES OF ‘VALENCIA’ ORANGE FRUITS

2014

Agro-hydrological models and field measurements to assess the water status of a citrus orchard irrigated with micro-sprinkler and subsurface drip sys…

2021

Compared to the micro-sprinkler irrigation, traditionally used in citrus orchards, subsurface drip systems (SDS) allow increasing the water use efficiency (WUE); when coupled with water-saving strategies, like regulated deficit irrigation (RDI), further increase of WUE are possible. Combining measurements of soil water content (SWC) and weather data with measurements of midday stem water potential (MSWP) makes it possible to identify irrigation scheduling parameters for the RDI. However, measurements of MSWP are destructive and time-consuming, and also require skilled operators. For all these reasons, the use of the agro-hydrological models, such as the FAO-56 model, can be considered a sur…

Relationship between tree water status and physiology, yield, and fruit quality in the table olive (Olea europaea sativa L.) cultivar ‘Nocellara del …

2012

Although the olive (Olea europaea sativa l.) is considered a xerophytic species, long periods of water stress and high temperatures during summer months can greatly affect plant physiology and productivity. In recent years, the use of plant-based water status indicators have become popular in the study of plant-water relationships and in the design of irrigation programs, particularly midday stem water potential (ψstem). The current trend in the irrigation of olive trees is in the development of Deficit Irrigation (DI) systems whereby the water is applied at a rate which is lower than evapotranspiration needs, resulting in only very small reductions in yield. Rather than working towards min…

Effetti di differenti metodi irrigui e volumi di adacquamento sullo stato idrico e sullo sviluppo vegetativo estivo di piante di agrumi

2020

Negli ultimi decenni, per massimizzare l’efficienza d’uso della risorsa idrica in agricoltura, si è cercato di migliorare le performance degli impianti di distribuzione oltre che implementare strategie di gestione che prevedano l’applicazione di condizioni di deficit idrico (DI) durante specifiche fasi del ciclo fenologico delle colture. Per l’applicazione di tali strategie è necessaria la conoscenza specifica del sistema suolo-pianta-atmosfera, in modo da evitare effetti negativi sullo sviluppo vegetativo e di conseguenza sulle produzioni. Obiettivo del lavoro è stato quello di valutare gli effetti di differenti modalità di distribuzione dell’acqua irrigua e volumi di adacquamento sullo st…

Implementing a cyber-physical system to monitor soil water status and environmental variables for irrigation scheduling

2018

The most advanced research on irrigation at farm scale, following the paradigm “more crop per drop”, has been aimed at the definition of strategies of precision irrigation, in order to optimize crop water productivity and to maximize the economic benefits without affecting environmental quality.Water saving management strategies, such as regulated deficit irrigation (RDI), can be effectively applied if supported by the real time control of soil/plant water status allowing the identification of appropriate irrigation scheduling parameters (irrigation timing and doses). This challenge can be achieved by integrating sensing technologies, internet of things and cloud computing supported with co…

Identifying the threshold of soil water content for the precise irrigation scheduling of a Citrus orchard under subsurface drip irrigation

2019

Proper irrigation scheduling requires the knowledge of the soil-plant-atmosphere system, including the relationships existing between its various components. During the last decade, the monitoring of soil water content (SWC) has been considered a standard way to determine when crops need to be irrigated. However, under drip irrigation systems in which laterals are laid on the soil surface or buried at a certain depth, the gradients of soil water content are rather high and therefore the threshold of SWC below which crop water stress occurs should account for the position of the sensors; the threshold, in fact, depends on the specific crop system, as well as on the relative position of the m…