Presented by: Academy of Agricultural Sciences Presented at: CNRRI Workshop, Hangzhou Date: 2/28/10

1. Current State of Rice Production and Research in DPR Korea Academy of Agricultural Sciences

2. 1. General Information

3. 1.1 Geography Location: Northeast of Asian Continent (between latitudes 43° to 38° north, and longitudes 124°10′47″ to 131°52′40″ east) Borders: Shared with PR of China and the Russian Federation, and surrounded by seas 80% of the territory : covered with mountains

4. 1.1 Geography Plains: mainly in the west and south Mountains: mainly in the north and east East seacoast: deep, not many indentations West seacoast: not deep, but big differences in tides (between high tide and ebb tide)

5. 1.2. Climate DPR Korea: typical temperate zone, with distinct changes of 4 seasons Annual average temperature: 8-12 ℃ Annual precipitation: 600-1400 ㎜ Hottest season : August with ave. temp. 23℃ Coldest season: January with ave. temp. -5 ～ -7℃ Rainy season: July and August

6. 1.3 Rice-Based Cropping System Main cropping season: May to September Prevailing system: rice mono-cropping For double cropping: wheat-rice, barley-rice and potato-rice systems

7. ● Rice is the main staple food. ● Decline in rice yield is largely due to unavailability of high yielding, and disease- and pest-resistant rice varieties, also low inputs such as fertilizers and chemicals and frequent natural calamities, including severe high and low temperatures, and flooding and drought. ● There are options to increase rice production such as integrated crop management, higher inputs, post-harvest technology, and sustainable farming methods, but the most urgent need is for availability of high-yielding rice varieties with resistance and tolerance to biotic and abiotic stresses that are able to increase rice yield per unit area.

8. 2. Progress of Rice Research in DPR Korea

9. 2.1. Outline of Rice Research Institute Mission: With the mandate of breeding high-and-stable yielding rice varieties by means of “green revolution” to meet the demands of the advancing agriculture, especially rice production. Being the primary rice breeding institution in the country, RRI is responsible for development and release of new rice varieties suitable to all rice-growing areas in the country. Structure: Research units and laboratories; namely plant breeding units (mainly for conventional rice breeding ), hybrid rice breeding unit, elite lines’ performance screening unit, unit for basic research, and biotechnology laboratory, and so on.

10. △ Major goals: - To develop hybrid rice with high yielding potential ( BT-type japonica intersubspeicfic hybrid rice with yield advantage of more than 30% over inbred rice, stable sterility, and good grain quality) - To develop a rice variety with long growth duration and high- yielding potential (by utilization of induced mutation, distant crossing and intersubspecific crossing , and wide hybridization with wild species such as Oryza rufipogon) - To develop early rice varieties suitable to second cropping - To develop a new rice variety suitable to organic farming with no or low input of chemical fertilizers.

12. 1.3 . Progress in Rice Researc h RRI has released over 150 rice varieties List of typical rice varieties released Years Variety Breeding method 1960s Rs No. 25 Introduction 1970s Py No. 15 Wide crossing 1980s Py No. 21 Japonica-indica crossing Py No. 33 Japonica-indica crossing O C No. 13 Anther culture 1990s Py No. 44, 45 Crossing Shc No. 9 Mutation Pd No. 9 Protoplast culture Pd No. 3 Anther culture 2000s No.11, 15 Backcrossing No. 7, 18, 19, 20 Japonica crossing

15. 3. Progress in Rice Cultivation

22. Yield components according to planting density of rice Planting density (hills / m ²) No. of panicles / m ² Ripened grains / panicle Ripened grains / m ² 24.2 363 74.8 27,154 30.3 366 75.9 27,839 36.4 395 69.8 27,571

23. Dry weight of rice plant according to width of row (g / m ²) Row width (cm) Tillering stage Heading stage Ripening stage 20 179 669 1,349 25 208 697 1,429 30 205 705 1,389

24. Yield rate (%) according to planting density (m ²) of rice

25. Growth rate of rice plant according to width of row (g / m ²/day) Row width (cm) Tillering stage Heading stage 20 3.6 15.8 25 4.2 17.0 30 4.1 15.9

26. Rice yield components according to width of row Row width (cm) No. of panicles / m ² No. of ripened grains / panicle No. of ripened grains /m² 20 260 97.9 25 420 25 275 93.9 25 850 30 276 92.7 25 610

27. Rice yield (m 2 ) rate in % according to width of row

28. No. of tillers and panicles of rice plants according to N fertilization time N fertilization time No. of tillers/m ² No. of panicles/m ² Rate of productive tillers (%) At transplanting time 368 233 61.3 17 days after transplanting 363 225 61.8 50 days before heading 432 236 48.8 40 days before heading 326 252 77.3 25 days before heading 290 262 87.1

29. Chlorophyll content (mg/fresh weight g) of rice plant according to N fertilization time

30. Yield components of rice plant according to N fertilizing time N fertilization time No of panicles / m ² Grains / panicle Ripening rate (%) At transplanting time 233 83.5 84.4 17 days after transplanting 224 79.4 82.0 50 days before heading 236 83.3 83.3 40 days before heading 252 89.6 82.4 25 days before heading 262 93.4 81.3

31. Yield rate (%) according to N fertilization time

35. 4. Production constraints During recent years, rice production has declined because of a substantial decrease in rice yields. The main constraints to sustainable rice production in the country are: ● Limited arable land ● Changeable and adverse natural climate conditions (critical high and low temperatures, drought and floods, etc.) ● Soils with low fertility ● Lack of production inputs ● Weeds, insects, and diseases, especially bacterial blight and blast ● Lack of rice germplasm to develop better new rice varieties ● Insufficient instruments for monitoring and research ( experimental equipment and facilities, etc.)

36. 4.3 Options to address constraints ● Make up for the limited arable land by increasing yield per unit area or by multiple-cropping ● Fertilization of soils by putting more organic materials (barnyard manure or compost, crop residues and green manure) into the soil ● Increasing inputs to agriculture (including fertilizer, herbicides, insecticides, fuel and farm machines, etc.) ● Development new rice varieties with higher yield potential and resistance or tolerance to stresses by combining conventional breeding with advanced techniques, especially biotechnology ● Collection and application of new rice germplasm through exchange, and acquisition of more knowledge and experience on rice breeding and cultivation through frequent international workshops, seminars and training courses, and so on ● Improvement of rice cultivation technique for achieving maximum yield

37. Thank You for Your Attention