유해영

7.2. Fertilizers Nutrients are essential to the rice plant because of necessity to complete its life cycle. The soil commonly does not provide sufficient nutrients needed by the plant. Hence, fertilizers are applied by farmers. Fertilizers contain important nutrients needed by the plant. Fertilizers containing nitrogen, phosphorus, and potassium are usually applied to the field.

7.1. Nutrients needed by rice plants There are 16 essential elements for rice plants. The major elements are carbon, hydrogen, oxygen, nitrogen, phosphorus, potassium, calcium, magnesium, and sulfur. The minor elements are iron, manganese, copper, zinc, molybdenum, boron, and chlorine. Among them, nitrogen, phosphorus, and potassium are needded in large amounts. 원 가운데 벼그림

6.6.3. Marking the field The surface of the field should be fully drained before marking the field. The farmer has to pass the wooden marker along the second base line. After finishing to mark one side of the field, the farmer has to pass the wooden marker across the field.

6.6.2. Establishing base lines Establish the two base lines. The first base line should be parallel to one of the border levees. The second base line should be perpendicular to the first base line, making a right angle between the two base lines. The right angle may be made by comparing with the corner of a book.

6.11. Replanting missing hills After transplanting, extra seedlings are placed along the alleyways of the field to be used for replanting. Replant missing and dead hills within one week after transplanting. Delay will result in less tillers, uneven crop maturity, and ultimately reduced yield.

6.10. Cutting leaves before transplanting The unbalance between transpiration from leaves and water absorption from roots may be occurred when tall seedlings with long leaves are transplanted. The unbalance can delay rooting. Long and droopy leaves of tall seedlings may reach to muddy water. This gives the chance to infect the plants with diseases. Cutting the leaves of tall seedling can preven..

6.9. Seedlings per hill The number of seedlings per hill depends on the methods of raising seedlings, planting spaces, planting times, planting seasons, and soil fertilities. Commonly 2-4 seedlings per hill are transplanted for wetbed or drybed seedlings. For about 10 days old infant seedlings, 4-8 seedlings per hill are transplanted. 2-4 seedlings per hill 4-8 seedlings per hill for about 20 d..

6.8. Depth of transplanting The proper depth of planting for about 10 days old infant seedlings is around 1.5 cm. For about 20 days old seedlings raised on wetbed or drybed , the proper depth of planting is 1.5 to 3.0 cm. The deep planting depth than 3 cm delays tillering and planting recovery. 그림 속 숫자 지울 것 For about 20 day old seedlings : 3 cm For about 10 old seedlings : 1.5 c..

6.7. Spacing of transplanting The commonly practiced is the square method ranging from 18² centimeters to 25² centimeters. some innovative farmers transplant seedlings at wider rows with closer distance between hills. Proper spacing depends on varieties, soil fertility, seasons, and the farmer's experiences.

6.6.4. Planting the seedlings Seedling bundles are distributed through out the field before transplanting. At the first base line, line the farmers up facing the field. The farmers have to plant the seedlings at the intersections of the lines, moving forward so that the markings will not be wiped out.