The experiment was conducted to evaluate the effect of different irrgation managements during poinsettia cultivation. The existing systems of calculationg evaporative demand and thus irrigation frequency are usually based on growing media moisture sensors or climatic sensors (temperature, relative humidity and solar radiation). Poinsettia ‘Primero Red' was grown in pots (1,2 dm3) in greenhouse and irrigated using drippers, according to three different levels: I - irrigation at 40% ±2, (v/v) of water content in growing medium, II - automatically controlled irrigation according to continuous readings of plant weight (all plants placed on special balance connected with irrigation controller) III - irrigation at 72% ±2, (v/v) of water content. The water content in growng media in each treatments was controlled using capacitance probes ECH2O-10 (Decagon Devices, USA). The obtained results showed that irrigation control system based on continuous readings of specially designed balance connected to the computer gave very good results in poinsettia cultivation. Plant in this treatment had the best plant shape and the highest bract area. Moderate water deficit (irrigation at 40% of water content in growing medium) resulted in significant reduction in transpiration and stomatal conductance and thus reduced plant growth and quality. ...
The increasing role of perennials in ornamental nurseries requires the elaboration of efficient and accurate irrigation control of this specific group of plants. The experiment was conducted in 2015 in Research Institute of Horticulture, in Skierniewice. The aim of the study was to determine the water requirements and designate the specific evapotranspiration crop coefficient Kc of several perennials, commonly grown in Polish ornamental nurseries. Water requirements of perennials were evaluated using weighing lysimeters. At the same time the recorded climate parameters allowed to calculate the potential evapotranspiration (ET0). Lysimeter measurements and meteorological data allowed determine specific to each species crop coefficient (Kc). The Kc values were determined by dividing ETc by ET0. The obtained results showed that irrespectively of plant growth phase there is strong correlation between climate parameters and real crop evapotranspiration (ETc) of six evaluated perennials: Anemone hupehensis 'Prinz Heinrich', Echinacea purpurea ‘Guava Ice', Hemerocallis, ‘Sandra Elisabeth', Salvia nemorosa ‘Mainacht' and Veronica spicata ‘Royal Candles Glory'. The Kc coefficients of all species were changed during the growth season and increased according to plant development and percentage of ground coverage of soil in the lysimeter by leaves. The strong, positive correlation was shown for daily and hourly ...
Poland has one of the smallest fresh water resources in Europe. Due to variability of Polish climate, irrigation became an indispensable element of intensive horticultural production. Recent study has shown that Polish farmers do not use any criteria to estimate plant water requirements for controlling irrigation, which leads to waste of water and energy. This is because userfriendly technologies enabling rational use of water resources are not easily available. The objective of the project is to develop an effective system for control of irrigation in ornamental nurseries, based on measurements of plant parameters, soil conditions and climatic data. To realize this approache the crop coefficient (k) for several important nursery species should be determined. Also the method of restricted irrigation (Regulated Deficit Irrigation - RDI) to control plant shape and plant quality will be tested on several important nursery cultivars. Additionally quantitative and qualitative evaluation of drainage water originated from container ornamental nurseries will be performed. The technology developed within the project will become the key element of the strategy of rational plant irrigation in ornamental nurseries. This is novel, hitherto not implemented approach to the problem of rational irrigation water use in plant production ...