CHAPTER 5 THE DOUBLE CROPPING PROGRAMME

The AREP double cropping programme aims to make optimum use of land that remains without a crop in autumn and early spring, after the main crops, rice and maize, have been harvested and before the main summer crops are planted. It permits the production of an extra crop of cereals by planting spring barley, winter wheat or potato crops prior to main crops of rice and maize. The western plains of the country, which include the regions below the 40-degree latitude, are the target areas of the double cropping programme. This zone has favourable climatic conditions for double cropping. The programme has the support of FAO and UNDP.

The viability of the double cropping programme, initiated in 1997 following the catastrophic years of 1995 and 1996, is now well established and a substantial increase in the food grain availability has been achieved. The programme has reduced substantially the need for food aid. In addition, the programme provides food during the lean period from June to September when food shortages are most acute. The double crops are not subject to flooding, which generally occurs in the case of the main summer crops during the months of July and August.

The initial stages of the double cropping programme had spring barley and then winter wheat as the double crops. Subsequently potatoes were also introduced as a double crop in spring, before the main summer cropping season.

Figure 4 Production of double crops - wheat and barley

The double cropping programme started in 1997 with 47 000 ha. Since then additional areas have been brought under double crops each year. The area under the double cropping programme amounted to 191 540 ha in 2001 (Table 10).

The contribution of double cropped wheat and barley during recent years rose from 46 930 tonnes in 1996/97 to 204 125 tonnes in 1998/99, followed, however, by lower production levels of 147 891 and 79 020 tonnes during 1999/2000 and 2000/01 respectively, owing to a severe drought (Table 11). The production of double crop potatoes also is given in Table 11. The production registered an increase from 170 423 (cereal equivalent) tonnes in 1998/99 to 224 015 tonnes in 1999/2000, then it fell sharply to 92 951 tonnes in 2000/01.

The production of double crop wheat and barley in the different regions is shown in Table 12.

The lower production of double cropped wheat and barley in 1999/2000 is accounted for by the substitution of part of the area under these crops with double crop potatoes. In 2000 there was an unprecedented drought.

The production of double crop potato by province during in 1998/99 and 1999/2000 is given in Table 13.

Figure 5 Production of double crop potato (cereal equivalent)

The productivity of double crops is shown in Table 14. Under optimum climatic and crop management conditions, yields up to four t/ha can be achieved for wheat and barley. The low yields are attributable mainly to the weather conditions and the insufficient use of inputs, mainly fertilizers.

The present yields of double cropped potatoes are around 10 tonnes per hectare and could be raised to 20 tonnes per hectare with the support of adequate agricultural inputs and improved agricultural, soil and crop management practices. In controlled experimental plots, yields up to 40 tonnes per hectare have been obtained.

Fertilizer requirements

Fertilizers are a key input for crop production, especially in intensive, high production systems with low soil fertility levels, but they are in short supply. Hence, considerable emphasis has been given to organic manure production.

The successful implementation of the double cropping programme is dependent on a higher use of inputs. The main crops of rice and maize require much higher rates of fertilizers to achieve the same yield levels after spring/winter crops that have not received adequate nutrient applications.

The input requirements for double crops form a relatively small proportion of the overall requirements for DPR Korean agriculture. Compared with a total of some 158 000 tonnes of plant nutrients during year 2000/01, which is considered to be sub-optimal, the requirements for the double crops work out at 30 400 tonnes of nutrients. However, in view of the substantial overall deficit in fertilizer availability and the preference given to the main crops, the availability of fertilizers for the double crops would be inadequate if it were not for the support the programme receives through the international agencies.

Constraints

In view of the short time between the harvest of the first crop and the planting of the second crop, double cropping puts a heavy demand on labour and agricultural mechanization.

The prevalent cereal-cereal rotation in the double cropping system represents a greater risk from pests and diseases. Outbreaks of armyworms starting from wheat and barley fields could pose a serious threat to the main maize crop, requiring plant protection measures. Similarly, spring potatoes as a double crop suffer from the incidence of blight and pest infestations such as Epilachna beetle, which may lead to a greater incidence of the same in the main potato crop.

A considerable proportion of the double-cropped area is in the rainfed zones. Irrigation is needed, but this depends on the power supply, which is a scarce resource.

Barley is the preferred crop for spring in most situations. Spring barley often runs the risk of late maturity due to the short season and lack of short duration varieties, which may eventually lead to premature harvests or even ploughing in of the crop.

In addition to the natural constraints such as adverse weather and poor soils, double cropping suffers from a number of physical constraints such as a shortage of inputs, especially fertilizers, insufficient irrigation, inadequate mechanization and plant protection measures and a lack of varieties with short LGP.

On some of the farms visited during the monitoring of the programmes, the irrigation pumps required replacement and repair. Lack of fuel was another bottleneck in the operation of the irrigation pumps. In general, the available agricultural machinery was old, inadequate and required renovation.

On most of the cooperative farms, a substantial area of additional land suitable for winter wheat/barley cropping is available and could be brought under winter cropping, provided that the needed resources such as tractors, tractor tyres and spare parts for the existing tractors, fuel, fertilizer, pesticide and labour are made available as required.

Efficiency

Of the three double crops i.e. winter wheat, spring barley and spring potatoes, winter wheat is considered the most reliable, since it has sufficient time to become established and is better able to deal with harsh winter and drought situations. It normally matures on time. There is also a dietary preference for wheat. Winter wheat yields are normally higher than those of spring barley.

Although the productivity of potatoes is higher, it is a relatively new dietary innovation and it is also subject to weather uncertainties (drought) and low yields due to early harvest.

The main crops, rice and maize, have an advantage over double crops in terms of yield, response to inputs and dietary preference. Returns from fertilizer use are higher with main crops compared with double crops. The late planting of main crops in double cropped areas can commonly result in a yield reduction of one t/ha at the same fertilization level. But despite the fact that the economic returns from fertilizer use on the main crops are higher in comparison to the returns from double crops, the double crops improve food security through additional food grain availability and also ensure supplies during the lean period.

There is scope for some rationalization of the overall strategy of input allocation. The experience gained so far suggests the following preferential sequence for the application of input resources:

i. Main crop rice
ii. Main crop maize
iii. Winter wheat
iv. Spring barley
v. Spring potato

It is suggested that, while main crop rice and maize should receive preference, winter wheat should receive its fertilizer requirement. Spring barley, in the light of the various risk factors mentioned earlier, may receive only the minimum basal rate instead of the full recommended rate.

With higher application rates and an improved quality of organic manures, the requirements for fertilizer application on potatoes could be reduced to some extent (only P as basal dose and a lower level of N application as top-dressing). The inputs saved by this measure could then be diverted for application to the main crops.

In view of the limited availability of fertilizers, their application might be focused on those provinces and areas that are better able to ensure the efficiency of the fertilizer use. It would also be prudent not to spread too thinly the relatively small input assistance received. Accordingly, the FAO-supported projects might be further concentrated in a few potential double-cropping provinces such as South and North Hwanghae and South and North Pyongan.

Support might be provided to improve the quality of the FYM by providing better methods of decomposition (use of EM), construction of lined pits and providing shades on top of the pits.

In the main lowland rice fields, where double cereal/potato cropping is not followed, green manuring would reduce the need for N fertilizers and would also add organic matter. Assistance in the selection of green manure crops and providing seeds of suitable green manure crops should be considered.

Prospects

Table 15 shows the gap between the present level of production and potential production from the present area. It is estimated at 240 tonnes annually. This excludes a possible additional area under double cropping if adequate resources become available. The government's overall objective is to extend the area under the programme to about 300 000 ha from the level of around 191 500 ha in 2000/01.

Almost five years' experience with double cropping in DPR Korea has provided valuable information concerning its strengths, weaknesses and potential. This could form the basis of a new, refined strategy aimed at a better and more effective utilization of available resources. Experience suggests that there is scope for reallocation of the scarce input resources between the various crops constituting the double cropping programme.