The response of two strawberry cultivars (‘Elsanta', ‘Sonata') to drought was examined by evaluating the yield and selected morphological and physiological parameters. Plants were subjected to two different water regimes: optimal irrigation (control), and reduced irrigation (water potential in the growing medium was maintained at a level -30 kPa, stress treatment). Genotypes differed in their response to water deficiency. Cultivar ‘Sonata' presented high rates of net photosynthesis with high value of water use efficiency (a ratio of photosynthetic rate to transpiration rate) under water shortage conditions. Drought stress reduced leaf area in all cultivars, but root development was retarded only in ‘Elsanta'. Under water deficiency conditions reduction of yield was higher for ‘Elsanta'. ‘Sonata' appeared to be more drought resistant which was reflected by both growth and yield parameters.
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Quantity, intensity and seasonal distribution of precipitation have an indu-bitable impact on soil moisture. Precipitation water could be used by plants only when percolates into soil and is retained as capillary water. In case of excessive amount or intensity of rain, part of water percolates below the root system level or runs off at soil surface. During two years of experiment (2009-2010) quantity and intensity of precipitation were observed and analyzed. Daily and weekly measure-ments of soil water content were done to assess the impact of intensity and quantity of precipitation on soil moisture changes in apple orchard. Total rainfalls for years 2009 and 2010 were higher from the multi-year average. Also, the temporal distribution of precipitation differed within and between the analyzed years, how-ever, the amount of rainfall collected during the vegetative period (May-September) constituted more than 50% of the total yearly precipitation. The results showed low efficiency of small rains. On average, during the vegetative period, minimal precipitation necessary to keep the soil water content at a stable level was 13-14 mm during a week. Efficiency of precipitation depended on the soil surface maintaining system. In case of soil maintained as a chemical fallow the highest efficiency was ...
The response of three strawberry cultivars (‘Elsanta', ‘Elkat', ‘Grandaro-sa') to drought was examined by evaluating the yield and selected morphological and physiological parameters. Plants were subjected to two different water regimes: optimal irrigation (control), and reduced irrigation (water potential in the growing medium was maintained at a level -30 kPa, stress treatment). Genotypes differed in their response to water deficiency. Under water shortage conditions, the rate of CO2 assimilation and efficiency of photosynthetic apparatus (expressed by chlorophyll fluorescence parameters) were the highest in ‘Elsanta'. On the other hand, the severe inhibition of photosynthesis was observed in ‘Elkat', which corresponded to the reduced biomass production. Taking all data into consideration it was concluded that cultivar ‘Elsanta' appeared to be more drought resistant which was reflected by enhanced physiological and yield parameters. ...
The objective of the study was to examine the influence of supplemental lighting with sodium light and LED on leaf gas exchange and growth of tomato transplants. During cultivation period (September - October) the transplants received supplemental artificial lighting provided by standard high-pressure sodium lamps (HPS) or high-power solid-state lighting modules with red, blue and far-red LEDs. Quantum irradiance in both combinations was maintained at the same level. The third group of plants (control combination) was grown under the natural light (without supplemental lighting). The following measurements were taken: leaf gas exchange (net photosynthesis and transpiration rate) and selected morphological parameters (fresh weight of plant organs, leaf surface area, plant height). The results showed that supplemental illumination using LED or HPS light sources affected growth and physiological responses of tomato plants. The higher rates of leaf gas exchange were found in the plants supplementary lighted (compared to the control ones). Supplemental lighting also resulted in enhanced plant growth, however no significant differences were found between the plants lighted with HPS or LED. The obtained results showed that HPS lamps can be replaced by LEDs in greenhouse lighting systems for tomato transplant production during periods with insufficient natural light. ...
Fifty research tasks are conducted within 2008 - 2014 Multi-Year Pro-gramme. One of them (2.2) is: Optimization of irrigation of fruit crops in Poland considering weather condition and soil water resources in major fruit production regions. The aim of this task is to develop internet service of irrigation recom-mendations and to develop and implement with the use of Internet simple methods of water requirement calculation for fruit crops. The test version of the service was launched in 2012. The web address of the service, which is located on a server belonging to Research Institute of Horticulture is: http://www.nawadnianie.inhort.pl. It is also possible to access the service from the main web site of the Institute: http://www.inhort.pl using "Serwis Nawodnieniowy" link. The web service contains current and historical meteorological data measured by several weather stations belonging to the Institute. Climatic water balance is also calculated. The web also contains glossary and scientific literature on irrigation and water management. Software applications for calculation of plant water needs and irrigation rates are important elements of the service. Using these calculators it is possible to determine evapotranspiration and plant water requirements computed with the use of measured weather parameters. They are designated for users who ...
In 1997 the Interdisciplinary Centre for Mathematical and Computational Modelling (ICM), University of Warsaw launched the Internet weather service which delivers numerical weather forecasts for individual consumers and has become a basis for several weather-related scientific projects. The project "Op-erational decision-making based on atmospheric conditions" (PROZA) (started in September 2009) utilizes data obtained from weather service provided by ICM. The Research Institute of Horticulture is one of the partners in the project. The institute participates in task 3 of the project: "Application of numerical weather forecasts in forestry and fruit farming". In the frame of this task, an Internet platform for forecasting of spring frosts and fruit crop water needs was developed. https://prognozy.projekt-proza.pl/. A user (after logging in) has access to the following information (forecast is prepared for 3 days): ETo, precipitation, climatic water balance and water requirements of major fruit crops. Data on amount of (easily) available water in root zone are also available. The information provided by the service make controlling of irrigation easier and thus improve agricultural water use efficiency. The estimation of forecasting quality showed that the accuracy of forecast was high proving its practical value for fruit growers. ...
Fruit crops have high water requirements. As sweet water is becoming scarce and expensive resource, development and improvement of irrigation tech-nologies, and introduction of new water saving practices (e.g. mulching to limit evaporation losses) is necessary. Relatively little research has been conducted to determine different re-sponses to unfavorable environmental conditions among various cultivars of fruit crops. Thus, studies have been undertaken at the Research Institute of Pomology and Floriculture to examine the influence of environmental stresses (mainly water deficiency) on plant life (growth, physiology and productivity). These researches are subjected to detailed assessment of genotypic differences in drought tolerance of various crop species. The obtained results are important not only for fruit growers, but also for plant breeders, as the enhanced resistance to stresses has become an important criterion in modern breeding programs. Balanced nutrition is essential for the health of plants. Modern practices allow farmers to apply fertilizers with water through drip irrigation systems (fer-tigation). Together with modern methods of nutrition diagnostics, fertigation has become a suitable tool for optimizing fruit crop fertilization. A new approach into sustainable water and nutrient management strategy should be a combination of modern irrigation and soil water monitoring techniques, elements ...
The usefulness of estimating hourly reference evapotranspiration for assessing the water requirements of plants over a 24 hour period was determined in the study. The values of hourly (ET0,h) and daily (ET0,d) evapotranspiration were calculated using the Penman-Monteith (PM) model. The daily ET0 was calculated automatically by the meteorological station, and the evapotranspiration values for individual hours were calculated using spreadsheet software. To verify the values of evapotranspiration calculated with these two approaches in relation to the actual water needs of grass, lysimetric measurements were performed. Additionally, substrate moisture content and temperature were measured using capacitance probes. The values of evapotranspiration estimated with the hourly PM model were higher than those determined with the daily model. An accuracy of the hourly model in relation to the data measured with a weighing lysimeter depended largely on the quality of the reproduction of meteorological parameters at the site of the crop. Observed underestimation of the actual daily evapotranspiration was presumably due to the use of air temperature values in the calculations (measured at a height of 2 m by the weather station). During strong solar radiation the air temperature was much lower than the temperature of the upper layer of the substrate ...
Spring frosts can cause very significant losses on fruit farms. The most common method of active protection against frost is sprinkling. The aim of this study was to assess the effectiveness of a sprinkling system used to protect apple trees against the effects of a spring frost. The experiment was conducted on the Mączewscy Fruit Farm. The orchard in which the observations were made is equipped with a system of sprinklers. When the temperature readings showed values close to zero, the sprinkler system was activated. Due to a limited water supply, one row of sprinklers had not been activated, and thus some of the trees were not sprayed at all. The assessment of fruit yield carried out in the autumn of 2015 demonstrated high effectiveness of the sprinkling used to protect apple trees against the spring frost. The frost had damaged most of the flowers of the unprotected trees, which resulted in a decrease in yield of as much as 85 - 93%. ...
In climatic conditions of Poland rainfall constitutes the main source of water for vegetation. Total amount of rainfall, its intensity and distribution influence soil moisture which has a major impact on plants' growth and development. Great variability and contrasts of rainfall are one of the main characteristics of Polish climate. The aim of the following investigations was to precisely analyze the spatial changeability of rainfall in Central Poland. Data concerning rainfall were collected during the vegetative season of April - October 2010 in 34 meteorological stations scattered in orchards all over Central Poland (the area between Skierniewice and Góra Kalwaria), and were the basis for the evaluation. Analysis of the data confirms the observation which states that there is a great spatial variability of sum of precipitation, its maximum amount and intensity as well as the longitude of dry and rain spells. Significant differences were observed between the stations located very close to each other - a few kilometers apart. In order to work out e.g. a reliable climatic water balance the rainfall must be measured directly on the investigated object.
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The experiment concerning irrigation controlling of gerbera cultivated in containers was done in 2012. Usually gerbera plants cultivated for cut flower production are irrigated using drippers. Correct adjustment of plant fertigation of plants grown in pots (volume and frequency of application) strongly influenced physical and chemical paramertes of growing media, plant productivity, flower quality. The systems controlling irrigation should also have the possiblity to prevent excessive leaching of nutrient solution during the period when plants requirements decreased due to unfavorable weather conditions. The aim of the experiment was to compare the effects of three methods of controlling irrigation on growth and flowering of gerbera ‘Surabaja' cultivated in containers (2 dm-3). The water consumption and leaching in each irragation treatment was also evaluated. Irrigation control systems were as follows: I - con-trol (irrigation 3 times a day, irrespectively of weather conditions, II - automatically controlled irrigation, according to water sensor readings in growing medium), III - automatically controlled irrigation according continuous readings of plant weight (all plants placed on special balance connected with irrigation controller). The aim of the experiment was to evaluate the precise control of irrigation of gerbera plants using specially designed balance, according to plant requirements and environment ...
Progress which can be observed in measuring instruments, calculation techniques, and it in general has considerably influenced the accuracy of mea-surements and as such has proved to be useful in weather forecasting. Agriculture seems to be the most dependent on weather conditions, therefore agrometeorolog-ical forecasting plays an important role in the whole system of decision making re-lated to agriculture and plant protection. A high level of verifiability of weather forecasting is the basic and required condition. The aim of the presented analyses was estimation of the quality of forecasting worked out with mesoscale numerical models. The accuracy of the forecasts (maximum, minimum and mean temperature, rainfall) was compared with the data obtained by automatic meteorological stations for Skierniewice (51º 57' N, 20º08' E), Biała Rządowa (51º 15' N, 18º 27' E) and Białousy (53º 24' N, 23º 13' E). The quality of forecasting was evaluated for the three stations using numerical models: UM and COAMPS. The forecasts were worked out at ICM of Warsaw University. Additionally, another forecast for Skierniewice prepared by Meteoblue from Switzerland, where NOAA/NCEP GFA model was used. The presented evaluation of the forecast of temperature and rain-fall showed a significant space and time diversity between the ...
Fruit production plays an important role in both national agriculture and economy. In order to keep the present supply markets, which means the actual production level, we have to ensure the high quality of fruit offered to customers. In our climate soil drought is one of the crucial factor significantly controlling the quantity and quality of the fruit crop. Therefore irrigation of orchards and small fruit plantations has become an indispensable element of fruit production. The de-velopment of irrigation itself is controlled by the shortages of water. It is important to optimize the ways of using our moderate water resources in the process of orchard development. It should be related to not only modern and economical irrigation systems but also with the introduction of rational criteria of irrigation to orchard farms. However, new technologies cannot find their way to predominantly small farms and the lack of reliable information makes the whole situations even worse. The information needed should be collected through surveys conducted during national conferences and fairs. The aim of the investigations was to estimate the area of irrigated orchard and plantations, collecting the information about the technological ideas and practical usage of irrigation criteria as well as the ...
