Potential use of the scheduler plant stress monitor in soybean

• Published in: Soil technology Vol. 6; no. 2; pp. 137 - 144
• Main Authors: Anda, A., Ligetvári, F.
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 1993; Amsterdam Elsevier; New York, NY
• Subjects: Agricultural and forest climatology and meteorology. Irrigation. Drainage; Agronomy. Soil science and plant productions; air temperature; Biological and medical sciences; crop yield; evapotranspiration; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; Glycine max; humidity; infrared thermometer; irrigation scheduling; Irrigation. Drainage; leaf area index; measurement; meteorological parameters; monitoring; phenology; plant temperature; seasonal variation; solar radiation; temperature; thermometers; water stress; water use efficiency; Hungary; Europe; Irrigation; Climate; Irrigation management; Water deficit; Environmental factor; Instrumentation; Water use efficiency; Glycine max; Forecasting; Water stress; Lysimeter; Grain legume; Leguminosae; Dicotyledones; Angiospermae; Evapotranspiration; Spermatophyta; Yield
• ISSN: 0933-3630
• DOI: 10.1016/0933-3630(93)90002-V

Much of work relating plant temperature to plant water stress has been done in arid regions. In 1989–1990, investigations were carried out verifying the validity of the Scheduler Plant Stress Monitor made by the Standard Oil Engineering Materials Company of the United States, in irrigation timing, under Hungary's changeable weather conditions. Three different water treatments were used: 1. ⊎ natural rainfall only (control), 2. ⊎ lysimeter study, where the water supply is in accordance with the water demand of plants, 3. ⊎ irrigation according to the instructions of the Scheduler. The monitor compares plant and air temperature differences to calculate stress index and irrigation timing. The measured indices were corrected for wind speed. Taking the varied water levels into account, the highest grain yield occurred in canopies watered by using the Scheduler instructions. In 1989, the yield increase was more moderate (16.5%) than that of the yield surplus in dry 1990 (38.1%), comparing to the results of non-irrigated control. The water-use efficiency in plant stands grown by the Scheduler control fell between the results of non-irrigated control and lysimeter study, independent of weather conditions. Use of the Scheduler may be recommended mainly in arid growing seasons, where yield increase is high enough to compensate for the additional cost of irrigation water. In Hungary, where the weather is very changeable it cannot be stated with complete confidence that the Scheduler is always an effective tool in irrigation planning. To clarify this problem further work is needed.