| The effects of root-divided fertilization on growth,development and yield in cucumber were investigated and the growth characters or cultivating effects on seed germination,seedling growth,low temperature inducement and heating integration for greenhouse saving energy in cucumber were simulated,by root-divided fertilization,measurement of theoretical value of base temperature of seed germination,simulation of seedling growth and low temperature inducement and heating integration for greenhouse saving energy in intellectualized growth cabin,with morden protected equipment and computer simulation technology,based on the hypothesis of optimal nutrient absorption in root-divided fertilization.The results of this study indicated as followings:1.In the treatment of standard solution +1/2 standard solution for each half of root zone in cucumber cultivar "Jinlvluyou" where total quantity of fertilizer was reduced by 25%,there was no significant reduction in total plant fresh weight and fruit yield,and there was significant reduction by 8.7%and 10.5%in total plant dry weight and fruit dry weight,respectively.In the treatment of 2 standard solution +water and that of 1.5 standard solution +0.5 standard solution in cucumber cultivar "Zhongnong 203" where the total quantity of fertilizer was constant,total plant fresh weight,fruit fresh weight,total plant dry weight and fruit dry weight were significantly increased by 23.2%and 16.6%,34.2%and 27.1%,10.4%and 5.6%,22.9% and 21.0%,respectively.Except in the treatment of massive element+trace element,there was no significant influence on leaf number and plant height in the other treatments.2.The operation to measure base temperature of cucumber seed germination was simple and the result was accurate by slow germination method designed independently under alternate temperature between day and night in an intellectualized growth cabin;the average measured base temperatures for cutivar 'zhongnong203' and 'chiyu401' were 10.48℃and 10.57℃;the effective accumulated temperatures at 70%germination rate were 686.95℃*h and 704.85℃*h; and the functions between germination rate and effective accumulated temperature were y=99.130/(1+1.704*exp(1-5.653x)) and y=95.460/(1+0.939*exp(1-4.267x)),respectively.3.The simulated experiment of seedling growth showed that the fresh plant weight,dry plant weight,plant height and leave number of cucumber seedling were significantly decreased by temperature reduction.;there was significant difference in plant height and leave number between different cultivars;the relations that LnDW(dry weight,DW) and relative growth rate (RGR) against days of seedling growth at different stages could be simulated by a quadratic function and liner function,respectively.Based on above,the CUSSIM model of cucumber seedling was established with POWERSIM software.4.The experiment of seedling inducement indicated that in comparison to control leaf numbers were significantly decreased,female flower numbers were significantly increased whereas there were no significant difference in plant height in the treatments 22/19℃and 25/19℃;both plant height and leaf number were significantly reduced while there was no significant influence in flower number in treatment 32/19℃;fruit yields were significantly increased by 6.1%,13.9%and 8.3%in treatments of 22/19℃,25/19℃and 32/19℃,respectively.5.In low night temperature treatment the blooming date of the first female flower was significantly advanced and the node of the first female flower was significantly lowered;the double effect of hign difference between day and night temperature and low night temperature significantly improved accumulation of total plant dry matter and fraction of dry matter allocated to the fruits,therefore increased the fruit yield with the constant daily sum temperature. The purpose of saving energy in greenhouse cultivation would be reached by optimal heating integration between day and night temperature with morden greenhouse when the sum temperature was constant.
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