A look at irrigation
Writers:
-Moisiadis Konstantinos (KUKOS-MOISIADIS AGRICULTURAL FOODS)
-Moisiadis Stavros (Irrigation Sector Manager, MOISIADIS GROUP).
In general, irrigation is the process of delivering water to crops through pipes, sprinklers, canals, sprinklers, pumps, and other man-made materials. Simply put, it is a system of advanced water delivery to crops so that they do not rely solely on rainfall.
It is necessary to meet the water requirements of crops and growth in general. It is an ideal solvent
Water and crops
Trees and plants, like all living organisms, need water in order to live and grow; its importance is readily apparent from the fact that the water content of plant tissues is very high. Leaves and fleshy fruits contain up to 95% water by weight. Water and mineral nutrients are supplied through the root system and transported to the aboveground.
Water is supplied to the soil by rainfall, snowmelt and irrigation. Water requirements vary depending on the plant species, soil and climatic conditions and other factors. When rainfall does not meet the needs, they are met by irrigation.
Irrigation
Irrigation in the general sense is the process of supplying water to crops.
The most common ways of irrigation are the following:
1. Drip irrigation. This method obviously has many disadvantages such as unnecessary waste of water, leaching of nutrients and their discharge into groundwater, soil suffocation and insufficient root oxygenation, weed growth, increased costs and many more.
2.Basin irrigation: A basin is constructed with walls about 30-50 cm high of an area equal to the projection of the crown of the tree (or plant) and water is piped there. This method also has most of the above disadvantages.
3. Sprinkler irrigation: Water is piped into the field under pressure and sprayed by special nozzles (injectors) over the entire surface of the soil (or a large part of it). The disadvantages here are the same as above, plus the fungal diseases that can result from the presence of moisture in the foliage.
4. Irrigation with microsprayers : Here the water sprayer (sprinkler) is placed on the ground, near the trunk or at some height above the ground and the irrigated area/sprayer covers an area about as large as the crown projection (which is usually the same as the root projection underground. It can also be used for frost protection if the sprayers are placed above the crown (tree crops). This irrigation method achieves some water savings compared to the above mentioned methods and more efficient use of water, better yields and money savings.
5. Drip irrigation. Suitable for precision systems, drip irrigation is based on the irrigation of the plant/tree/pruning system and not just the irrigation of the soil. The water is transported to the field by pipes and delivered to each plant/tree on the line in the form of drips. The advantages of this system are many and will be mentioned in a new article (it eliminates the above disadvantages).
(See here the advantages of drip irrigation)
The data in the country
All the above ways are – more or less – familiar to the modern Greek producer. What is not known and often the producer hesitates to make the decision to change the way he irrigates is the information, the details and the possible failure of a poorly designed and incorrectly planned irrigation system.
At MOISIADIS we operate with a high level of expertise and professionalism and create solutions, not simple installations.
Finally, the root system of plants in order to function smoothly needs energy which comes from respiration and for this reason it must have oxygen at its disposal. Plants and trees are very susceptible to suffocation when they have foliage and the temperature is high. Water is transported from the root system to all parts of the tree due to the difference in osmotic pressure. It is lost mainly due to transpiration through leaf stomata and evaporation. This process is influenced by the plant species and the prevailing environmental conditions.
In the conditions of our country, where we are facing problems of water scarcity and unsuccessful irrigation, stress phenomena are often observed. Plant/tree stress occurs in every growing season for many factors (e.g. extreme temperatures, drought or excessive rain, salinity, heavy metals, root system anoxia, pest and disease attacks, herbicide contact on leaves, excessive weed germination, etc.).
Plant stress and losses
We will only briefly discuss water stress under conditions of water shortage.
Water shortage is the most limiting factor in plant growth, reducing the quantity and quality of production. It is indicative that in cases of intense water requirement of fruit trees at the stage of cell elongation and under conditions of high temperature and radiation, the fruit cannot reach its final size resulting in reduced “tonnage” and quality.
Physiologically, the stresses caused by water deficiency involve a reduction in the rate of cell growth, cell wall synthesis, protein, protochlorophyll, nitrogen and secondary metabolism enzymes (nitrate reductase). This is followed by a decrease in photosynthetic activity and an increase in ageing and apoptosis hormones (ethylene and ABA) resulting in ageing, necrosis and apoptosis of various organs.