RESEARCH ON THE WATER REGIME OF TOMATOES CULTIVATED IN SOLARIUMS|
Mihai JURIAN, Marcel DÎRJA, Viorel BUDIU, Beata JURIAN, Alexandru Silviu APAHIDEAN, Maria APAHIDEAN, Ioan PAVEN
University of Agricultural Sciences and Veterinary Medicine, 3-5 Mănăştur Street, Cluj-Napoca, România.(contact e-mail: firstname.lastname@example.org)
The rational application of the irrigation is extremely important for the obtaining of high crops, of superior quality, economically justified. Applying too high water quantities through irrigations has, besides the negative effects on plants and soil, dezastrous effects on the economic efficiency of the agricultural exploitation. In an age when in some areas of the Earth, millions of people die every year due to the lock of water or to its low quality, when wars are declared over water, when the water from the civilized areas gets more and more expensive, the irrigations applied wrongly become an unallowed water waste. Of course, applying too small water quantities through irrigation has also negative effects on cultivated plants and, automatically, on crops, thus affecting the economic efficiency of the agricultural exploitation.
Material and methods
Our experiment was made in the solarium from the University of Agricultural Sciences and Veterinary Medicine Cluj - Napoca, in 2003. The experiment was bifactorial, i.e., the influence of two factors being followed, with the following gradients. By having combined these, there resulted six experimental variants, as it follows (table 1):
Table 1. Experimental variants
|Watering method||Time of watering||Variants' name|
|Trickle irrigation||90 % from A.H.I.|
70 % from A.H.I.
50 % from A.H.I.
|Irrigation through drains||90 % from A.H.I.|
70 % from A.H.I.
50 % from A.H.I.
The water consumption of a crop, based on the evaporation at ground level and on the perspiration of the plants is called evapoperspiration (EP).
For determining the EP were used the direct method based on the water balance in the soil:
Ri + Pv + Sm + Af = Rf + REP, where:
Ri - the initial stock of water in the soil (in the beginning of the vegetation period)
Pv - precipitation during the vegetation period (in our case, having crop placed in protected areas, where the water coming from precipitation doesn't reach, Pv = 0)
Sm - irrigation norm (the sum of the wetting norms)
Af - the contribution of the freatic waters to the existing water (in our case, the freatic water are found at a depth higher then 5 m, so Af = 0)
Rf - the final water stock in the soil (at the end of the vegetation period)
REP - real evapoperspiration
Results and discussion
Thus, by utilizing the formula presented in the " material and method" subchapter, we have computed the total water consumption for each variant. The results obtained are shown in Table 2.
Table 2. Water consumption for the experimental variants
The production results obtained with each of the six experimental variants can be followed in Table 3.
Table 3. Average fruit yield per variants and replicas (t/ha)
| ||I||II||III|| |
Knowing the water consumption of the crops and the obtained yields, by comparing these, we obtained the water capitalization coefficients (Wcc, which shows the water quantity (m3) consumed by the plants to produce 1 kilogram of fruits.
Wcc= water consumption (m3/ha) / average yield (kg/ha)
Table 4 contains our results regarding the water capitalization coefficients.
Table 4. Water capitalization coefficients
|1||P90||7848.5 ||63900 ||0.1228 |
The irrigation of the tomatoes in solariums by furrow leads to the wasting of too big water quantities due to the need of applying high irrigation norms. This irrigation method is totally unrecomandable for this culture, given the fact that the obtained yields are inferior to those obtained in the case of the variants irrigated by dripping.
The irrigation by dripping can lead to the obtaining of superior yields than those obtained in the case of furrow irrigation, while using same low quantities of water. This can be explained by maintaining at the level of the plants' roots a constant humidity, due to the reduction of water losses through infiltration and evaporation.
The water capitalization coefficients show that the experimental variants irrigated by dripping use the water better than those irrigated by furrows. The water capitalization coefficients were bigger in the case of furrow irrigation, showing that the use of this irrigation method applied to the tomatoes in solariums is a total waste of water, without even having the benefice of obtaining higher crops then in the case of dripping irrigation.
Thus, we solidly recommend you to avoid using furrow irrigation for the tomatoes in solariums and to replace it with dripping irrigation, which is more favorable both to the plants and to the producer.