Rice can't grow well in cold waterlogged paddy field due to low temperature. Activity of rice root isn't also high and the growth is late, so the maturing rate is so low that the harvest isn't high.
Realizing characteristics of the soil as this and solving the required cultivation technical problems have an importance signification to raise the crops per ha and solve the food problem of people.
We made clear the characteristics of paddy rice in the cold waterlogged soil and studied the reasonable cultivation methods such as the rice-transplanting period, number of plant per pyong, water management and application method of fertilizer which are arisen for application of big seedling cultivation technique on the wide ridge.
First of all, we cleared up the characteristics of the field-forming characteristics of paddy rice.
Temperature of the soil was as low as 2~4℃ than that in common soil and rooting was late more than 4 days. After rice-trans planting, rice's height is short and tillering was also late.
And ear number per pyong and kernel number per ear, maturing rate were low. so the yield per ha was down more than 1.5t.
Also, we cleared up the effectiveness of big seedling cultivation technique application on the wide ridge in the soil.
Introducing the wide ridge culture in the soil made that soil's temperature was high and tillering speed was also quick after rice-trans planting, As a result, rice's growth was improved.
Reasonable depth in the wide ridge is 20cm in the soil.
Wide ridge culture increases soil temperature to a certain degree. But transplantation in May gives stress to the rice growth due to the influence of low temperature.
Thus it is of also important to choose suitable seedlings for cold waterlogged soil.
Wide ridge culture makes it possible to activate root and increase dry weight compared to common seedling.
As for wide ridge culture, transplanting time of big seedling is between June. 15-20 with more than 8 leaves.
60-70 plants per pyong is the most favorable while corrugation irrigation alone is needed after establishing.
The overall result showed that big seedling transplanting on wide ridge is able to shorten establishing period and provide favorable conditions to increase rice yield.
