| In this study, a new auto-irrigating cultivation system was developed usingporous ceramic pipes with the negative pressure. The ceramic pipe can irrigate,warm soil and supply nutrients simultaneously. The concept of new cultivationmethod-Real-fertirrigation has been discussed. And then, the developed auto-controlling irrigation system was applied to study the effect of soil moistures onplant growth, yields, physical and chemical properties and transit injury ofstra~berIy fruits. The main results are summarized as following:1.In this study, a new auto-controlling irrigation cultivation system usingporous ceramic pipes with the negative pressure was successfully developed. Thesystem made it possible to keep soil moisture at a suitable level for growth anddevelopment of plant in all the time. It was considered that the developed systemhas the function of "recognizing" the soil moisture and the function of adjustingirrigation rate by itself in relation to the soil moisture. Both simulating results ofthe finite element method and the observed results show that the soil watercontent in the new system could always be maintained at suitable value(0.40?.41) for the growth of lettuce throughout the experiment, while the soilwater content in the surface irrigation fluctuated widely from 0.36 to 0.45. Thegrowth and yields of lettuce cultivated in the new system were significantlybetter than that in the usual soil culture with the surface irrigation.2.A new irrigating and soil-warming cultivation system using porous ceramicpipes was developed. There was only one porous ceramic pipeline that was usedsimultaneously as an irrigating pipe and as a warming pipe in this developedsystem. The average soil temperatures for daytime and night in the warmingtreatment were 20.6, 15.30C, which were 4.8 and 4?0 higher than those in the3no-warming treatment. The average soil temperatures for the day and the night inthe cooling treatment were 1.4 and 2.l~ lower than that in the no-warmingtreatment. The cultivation experiment with lettuce verified that this system waspractical for irrigating and warming soil simultaneously. Because the irrigatingwas also from the heating pipe, the problem of the soil drying around the heatingpipe was overcome. The required temperature (y) was obeyed to the powerfunction of the air temperature (x) Y=59. 5X0 ~. The warming-irrigation systemalso attained the maximum yield as compared with those of others.3.In this cultivation system, the nutrient can be auto-supplied to root systemcontinuously and timely, when necessary. The ceramic pipe can not only supplynutrients to soil but also remove excessive nutrients from soil. It indicates thatthe ceramic pipe can control soil nutrients to some extent. The component andcontent of soil solution in developed system were stable as in soilless culture;moreover, p11 and EC of soil solution were also stable although withoutadjustment during cultivation, which result from the cushioning ability of soil.Therefore, the developed cultivation system was a real fertirrigation system.4.The effects of soil moisture on the plant growth, yields, physical andchemical properties of strawberry fruit were carried out by use of the new auto-irrigation system. It was showed that plant height, number of leaves, fruit weight,fruit diameter, fruit number and yields gradually decreased with the decreasingof soil moisture. The yields in high, middle, low and extreme low treatmentswere 720.3, 743.8, 587.0 and 380.9g. respectively. The Deficit Irrigationdecreased water content of fruit, increased fruit hardness, soluble solid content,titratable acidity, soluble solid-acid ratio and the content of ascorbic acid. Thesoluble solid-acid ratios in four treatments were 13.12, 15.20, 16.80 and 1...
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