Author:
Grishin A P,Grishin A A,Grishin V A,Semenova N A
Abstract
Abstract
It is shown that in earlier studies, the results of which were reported in the article "Digital wireless mini-sensor of plant thermoregulation", the presence of three phases of the thermoregulation process was experimentally revealed, and the task of further research aimed at theoretical and experimental confirmation of the hypothesis was set that the maximum productivity of the plant is ensured at the optimum air temperature and the maximum consumption of the nutrient solution. A number of statements, which do not require proof, are presented about the relationship between photosynthesis and air temperature and their effect on productivity. The article sets the task of developing a universal algorithm for maintaining the air temperature. Thermoregulation processes of plants were chosen as the object of research. These included the temperature of the leaf surface, the temperature difference between the leaf surface and the ambient air, and the flow rate of water for cooling evaporation. Two plant samples were chosen as the subject of research: salad variety "Red Dubolistny" and tomato variety "Fighter" (Buyan). The change in the mass of water in the container was measured using an ML-A01 balance with a measurement accuracy of 0.01 g, and the temperature was measured with an infrared IR thermometer Kelvin IKS 4-20 / 5. Data were recorded at 5-minute intervals and repeated three times over a short period of time. The plants were placed in containers with an airtight lid, which contains an oil seal for the plant stem. Moreover, the roots were placed under a lid with an aqueous nutrient solution. At the boundary of phase 2, there is a zone of maximum consumption of nutrient solution through plants, while the temperature is optimal, which corresponds to the maximum rate of photosynthesis. Further, the object of research was the process of forming a productive mass in a plant, depending on the air temperature. The weight of the plant was measured separately, on more accurate scales of the ML-A01 brand with a measurement limit of 100 g and a graduation of 0.01 g, twice a day: in the morning and in the evening. Next, weight gain dependence graph on the air temperature was built and the trend was found in the form of a second-order polynomial, which had a maximum. Its coordinates are 29.29 Co and 0.75 g of green weight gain. The maximum increase is provided at an air temperature corresponding to the boundary of phases 2 and 3. From previous studies, we found this value, it was 29.36 Co, that is it differs by 0.2%.