Multiple-cropping practices in Asia and the Far East

Agriculture and Environment, 2 (1975) 219--228 © Elsevier Scientific Publishing Company, Amsterdam -- Printed in The Netherlands

M U L T I P L E - C R O P P I N G P R A C T I C E S IN A S I A A N D T H E F A R E A S T W.C. BEETS

Chibero College of Agriculture, Norton (Rhodesia) (Received June 26th, 1975) ABSTRACT Beets, W.C., 1975. Multiple-cropping practices in Asia and the Far East. Agric. Environm., 2: 219--228. Research on multiple-cropping practices in the tropics has somewhat been neglected as a result of the influence of monocropping oriented research in the Western world. However, recently, interest in this field has increased. In areas with labour surpluses due to overpopulation, under-employment, and a low degree of mechanization, multiple cropping practices are desirable and can increase total production substantially. The cropping system should be adapted to the local agro-climate. An example of a cropping system is given for tropical areas in Asia with one pronounced rainy season. Suggestions are given for fertility maintenance and chemical fertilizer applications. The economics of the system is discussed based on a trial in Thailand, the author's suggested system in Indonesia, and work in Taiwan. Multiple cropping systems can be of great help to make better and more intensive use of available resources. INTRODUCTION Multiple c r o p p i n g in essence represents a p h i l o s o p h y o f m a x i m u m c r o p p r o d u c t i o n per unit o f land t h r o u g h p r o d u c i n g several crops within one c a l e n d a r year, or o t h e r relevant time span, with m i n i m u m o f soil deterioration and m a x i m u m use o f fertilizer and o t h e r inputs. Multiple c r o p p i n g has been practised for centuries in s o m e parts of the world, e.g. s y s t e m s o f three crops a y e a r were practised in China during the Ching D y n a s t y (1684). In the Western world, where the m a j o r part o f adv a n c e d scientific agricultural t e c h n i q u e s were developed, little a t t e n t i o n has been given t o multiple c r o p p i n g since research in these c o u n t r i e s has been f o c u s s e d on systems t h a t have m e c h a n i z a t i o n as one of their m a j o r factors. A pre-requisite for m e c h a n i z a t i o n is a s y s t e m o f m o n o - c u l t u r e s . Multiple c r o p p i n g s y s t e m s d o n o t o f t e n allow a high degree o f m e c h a n i z a tion, since access to the field f o r o p e r a t i o n s such as weeding, fertilizer applic a t i o n and harvesting is very limited. T h e degree o f m e c h a n i z a t i o n in Asia and the Far East is still very low, f o r such reasons as an a b u n d a n c e o f l a b o u r and a lack of capital. In m a n y c o u n t r i e s in Asia and the Far East the population is very dense. Bangladesh has 563 persons per k m 2 S o u t h K o r e a has 342, a n d m a n y regions in these c o u n t r i e s have a p o p u l a t i o n d e n s i t y as high

220 as 800 p e r s o n s p e r square k i l o m e t r e ( P r o d u c t i o n Y e a r B o o k , F A O , 1972). This m e a n s t h a t o n e ha o f arable land has to s u p p o r t u p t o 8 p e o p l e a n d the average f a r m size is 0.3 to 0.6 ha. In these c i r c u m s t a n c e s , a very intensive u t i l i z a t i o n o f available land using the f a c t o r s o f p r o d u c t i o n in the given p r o p o r t i o n , i.e. m u c h l a b o u r and scarce capital, is o f p r i m e i m p o r t a n c e . Multiple c r o p p i n g s y s t e m s can be of great h e l p t o m a k e b e t t e r a n d m o r e intensive use o f available resources in c o u n t r i e s in Asia a n d the F a r East. I t has b e e n a v e r y distinctive f e a t u r e o f agricultural d e v e l o p m e n t in T a i w a n t h r o u g h o u t the years. H o w e v e r , in o t h e r c o u n t r i e s these studies were somew h a t p u s h e d b a c k by the i n t e r e s t in the green r e v o l u t i o n : t h o u g h interest in this field has r e c e n t l y increased again, e.g. at the I n t e r n a t i o n a l Rice R e s e a r c h I n s t i t u t e at Los Banos in t h e Philippines a n d the Kasetsart University, Thailand. THE DIFFERENT SYSTEMS

Mixed or inter-cropping With this s y s t e m , m o r e t h a n one c r o p is p l a n t e d on the s a m e p l o t o f land. T h e d i f f e r e n t c r o p s are p l a n t e d at the s a m e t i m e or w i t h a s h o r t interval. This m i x i n g o f d i f f e r e n t crops can be d o n e in an o r g a n i z e d m a n n e r , w i t h a f i x e d p a t t e r n o f spacing a n d n u m b e r o f plants per area, or in an u n o r g a n i z e d m a n ner. We will o n l y be c o n c e r n e d w i t h the first. M e c h a n i z a t i o n is v e r y difficult. This f o r m of agriculture is m a i n l y f o u n d in d e v e l o p i n g countries.

Relay Cropping S o m e w e e k s or m o n t h s b e f o r e a c r o p is harvested, a s e c o n d c r o p is p l a n t e d in b e t w e e n the r o w s of the first. This is o f t e n p r a c t i s e d in regions of s h o r t d u r a t i o n of rainfall. M e c h a n i z a t i o n is difficult. This f o r m o f m u l t i p l e c r o p p i n g is wide s p r e a d in T a i w a n a n d r a t h e r s o p h i s t i c a t e d s y s t e m s have been developed.

Multiple Cropping More t h a n one c r o p on the s a m e piece o f land, b u t n o t s i m u l t a n e o u s l y , in one c a l e n d e r year. M e c h a n i z a t i o n is possible a n d this f o r m o f agriculture can be f o u n d in m a n y countries.

Combinations It is m o r e c o m m o n to see the d i f f e r e n t f o r m s in c o m b i n a t i o n r a t h e r t h a n on t h e i r own. Especially a c o m b i n a t i o n o f m i x e d a n d relay c r o p p i n g is v e r y c o m m o n . An e x a m p l e is s h o w n in Figure 1. Maize is r e l a y - c r o p p e d w i t h a m i x t u r e o f cassava a n d c o w p e a s .

221

Figure 1. A very intensive cropping system. The tops of the maize are fed to cattle. Cassava and cowpeas are then planted between the maize. CROP PHYSIOLOGY AND AGhONOMY T h e agro-ecological c o n d i t i o n s in a m u l t i p l e c r o p p i n g s y s t e m are v e r y diff e r e n t f r o m c o n d i t i o n s in a m o n o c u l t u r e . Multiple c r o p p i n g s o m e w h a t resembles the n a t u r a l c o n d i t i o n s . A g r i c u l t u r e can be d e s c r i b e d as a " s y s t e m w h e r e m a n o n l y p e r m i t s n a t u r e to grow w h a t he w a n t s t o be g r o w n " . T h e c o n c e p t o f o n l y p e r m i t t i n g o n e p l a n t at t h e s a m e t i m e was a p p r e c i a t e d v e r y early in h i s t o r y , a n d t o g e t h e r w i t h the n e e d o f m e c h a n i z a t i o n , this t e n d e d to f a v o u r the d e v e l o p m e n t o f s y s t e m s o f m o n o c u l t u r e . H o w e v e r , m o n o c u l t u r e has m a n y disadvantages s o m e o f w h i c h can be s u m m a r i z e d as follows: - - In the beginning o f the growing p e r i o d t h e light s u p p l y e x c e e d s the requirem e n t s . Later, v e r y o f t e n , n o t e n o u g h light is available since o v e r s h a d i n g t a k e s place a n d plants c o m p e t e f o r light. - - T h e n u t r i e n t s a n d soil m o i s t u r e r e q u i r e m e n t s are in p e a k s and t h e soil is o f t e n n o t c a p a b l e of s u p p l y i n g the e n o r m o u s q u a n t i t i e s o f n u t r i e n t s a n d m o i s t u r e n e e d e d during t h e high r e q u i r e m e n t periods such as tillering a n d panicle initiation of cereals. - - Because o f o p e n spaces in the beginning o f the growing period, w e e d c o n t r o l is c o s t l y , a n d soil erosion a n d soil n i t r o g e n losses are c o m m o n . - - P l a n t p o p u l a t i o n s are always k e p t high w h i c h results in v e r y intensive con-

222 tact between individual plants. Hence certain crop pests and diseases can spread very quickly, and a high population of crop destructing pest and disease species can build up very rapidly. Unlike in monocropping, in the case of mixed cropping, the soil is uncovered for only a short period after planting. The light requirements of the different crops make higher photo-synthetic activity possible at one given time, and the soil nutrients, especially the supplied fertilizers, are better used, since the requirements of the different plants grown are n o t the same and do n o t occur at the same time. The spreading of pests and diseases is also reduced since each crop forms a barrier. From the above, it can be u n d e r s t o o d that it is of prime importance to find the right combination of crops, and to plant them in such a way and at such a time that the combination of plants can make m a x i m u m use of the available inputs. In terms o f agronomy the following factors have t o be considered: -- Type of crop (legumes or non-leguminous) -- Spacings, grouping and plant populations of the different crops*. -- Time o f planting and growing periods of crops and varieties. Therefore, the following suggestions can be made: An ideal combination is a legume and a plant with high nutrient requirements such as, for example, maize inter-planted with ground-nuts or cassava inter-planted with soyabeans. For the wet tropics with one p r o n o u n c e d rainy season, the following combination of mixed cropping and relay cropping is suggested (see Fig. 4). At the start of the rains (in this example in November), strips of maize and upland rice are sown. After maturing of the crops their places are taken by cassava or sorghum, groundnuts or soya-beans. The spacing of the maize or sorghum is 200 × 25 cm and 200 X 50 cm for cassava. The spacing of rice, groundnuts or soya-beans should be 25 X 25 cm, which will result in 8 rows of rice or groundnuts between 2 rows of maize or cassava. FERTILIZER REQUIREMENTS AND SOIL FERTILITY The need for crop rotation has somewhat been changed since the introduction of inorganic fertilizers. Chemical fertilizers, even though t hey contain no organic matter, are an i m p o r t a n t means of adding organic m a t t e r to the soil by producing more abundant crop residues and roots. However, this applies only where ab u n dant fertilizers are available and are applied in a wellbalanced scientifically supported manner. In Asia, where a growing shortage of the c o m m o d i t y exists, the need for conventional crop rotation is still obvious. A deep-rooted legume such as soya-beans, and a surface feeder such as maize, is an ideal combination for mixed cropping for the following reasons: - - T h e n u t r i e n t a n d soil m o i s t u r e r e q u i r e m e n t s o f t h e t w o crops are n o t t h e same a n d do n o t o c c u r at t h e same time. * In figure 2 and 3 maize is inter-planted with cassava; in Figure 2 in-between the rows of maize and in figure 3 within the rows.

223

Figure 2. I n d o n e s i a n Agricultural E x t e n s i o n S t a f f s h o w i n g a m i x e d c r o p p i n g s y s t e m in o n e of the m o s t densely p o p u l a t e d areas of Java (near Madiun).

Figure 3. Cassava relay, p l a n t e d w i t h i n t h e maize rows.

r

r

r

r

r

r

r

r

M

r

r

r

r

r

r

r

r

M

I',!

r

r

r

r

r

r

r

r

H

Dec.

~,~.

r

r

r

r

r

r

r

r

M

Jan.

.~;

r

r

r

r

r

r

r

r

M

r

r

r

r

r

r

r

r

Feb.

C

g

g

g

g

g

g

g

g

C

Yar.

g

g

g

g

g

g

g

g

Apr.

C

g

g

g

g

~

g

g

g

C

g

g

g

g

g

g

g

g

~ay.

C

g

g

g

~

~g

g

g

g

C

Jun.

g

g

g

g

g

g

Jul.

C

C

Aug.

T h e g r o w i n g p e r i o d f o r t h e d i f f e r e n t c r o p s a r e : M a i z e = 9 0 d a y s ; U p l a n d rice = 1 2 0 d a y s ; g r o u n d n u t s Cassava = 8--12 months.

C

C

Oct.

= 130 days;

5ep.

rainy season a

a M = M a i z e ; C = C a s s a v a ( 5 0 c m i n t e r v a l ) ; r = rice ( 2 5 c m i n t e r v a l ) ; g = g r o u n d n u t s ( 2 5 c m i n t e r v a l ) .

M

M

Nov.

A combination of mixed cropping and relay cropping for the wet tropics, with one pronounced

Figure 4

C

C

;':v

bO bD

225 Soya-beans will be able to use nutrients that cannot be used by maize and which may be leached out in the case of monocropped maize. -- The soya-beans quickly establish a soil cover which is beneficial to the maize, and for the general soil conservation. The soil preparation suggested for the cropping pattern given in Table I is a ploughing to a depth of 20 cms and leveling by hoe prior to planting. Only minimum tillage to enable planting of the second crops (cassava, groundnuts) is necessary. In this context it must be stated that frequent stirring of soil, due to cultivation, leads to quick oxidation of organic matter. In view of the shortage of fertilizers, it is difficult to advise on fertilizer application. However, a minimum of N: P2Os : K~O = 100:65:40 kg/ha can be advised. The nitrogen (in the form of urea or sulphate of ammonia) is given in five split applications of 20 kg/ha. The first three applications will be broadcasted and equally divided between the maize and the rice. Time of application is at planting time, when the maize is at knee height, and at the silking stage of the maize. The remaining two applications are given to the cassava, 3 and 6 months after planting. Thirty five kg P2Os is broadcasted and incorporated into the soil with the last soil cultivation, 30 kg is stripped along the rows of maize. All potash is incorporated into the soil with the last soil cultivation. This practice is advised, since splitting of nitrogenous fertilizers is almost always beneficial in the tropics, and phosphate requirements of maize are high in the early growing stage. The secondary crops are not given any fertilizers except for N top-dressing of the cassava. It is expected that these crops can benefit from the fertilizer residues of the first planted crops. With the now c o m m o n practice of planting one crop, leaving the land fallow and burning off the weeds before cultivation for the next crop, a great part of the fertilizer residues are taken up by the weeds and are lost when the weeds are burnt. -

-

ECONOMICS As mentioned before, the main feature of multiple cropping is optimum utilization of input resources. The main consideration are: -- Availability of soils and soil conservation. Climate. Risks involved in growing crops. Labour, capital and facilities available. Most forms of multiple cropping should only be practised in a region where labour is a b u n d a n t and the degree of mechanization is low (mostly due to scarcity of capital). An abundance of labour is the result of a dense population, which also results in a scarcity of agricultural land. In the areas described above, the factor "labour costs" is not an u n i m p o r t a n t factor in economical calculations, -

-

-

-

-

-

226 since the people involved would not be able to earn an income from any other source than from farming. In Thailand, a mixed cropping trial with maize interplanted with soya-beans was carried out in 1972 (Kasetsart University, D e p a r t m e n t of Agriculture, 1972 Annual Report). The objective of the e x p e r i m e n t was to compare the yield of maize, at varying plant populations when inter-cropped with soyabeans, with that o f maize planted as a monoculture. Maize and soya-beans were planted (a) at the same time and (b) soya-beans 8 days ahead of maize. The maize planted as a m o n o c u l t u r e was spaced 75 X 25 cm. (53 333 plants/ ha). The mixed cropping had rows of maize spaced 150 cm apart and 2 rows of soya-beans between the rows of maize. The in-row spacing was varied from 16.6 cm to 8.33 cm to obtain plant populations of 40 000--80 000 plants/ha. The results o f the trial are summarized in Figure 4. The maize planted as a m o n o c u l t u r e yielded 4 202 kg/ha of dry grain (maize planted 8 days later than soya-beans). At the prevailing local m arket price (US $ 0.06 per kg), this had a value o f US $ 252.12. When maize and soya-beans were planted in a mixed cropping system and the plant population of maize 53 333 plants/ha, the yield of maize was 3 310 kg/ha and soya-beans 617 kg/ha (maize planted 8 days later than soyabeans). The combined value was US $ 328.17 per ha. (Market value o f soyabeans US $ 0.21 per kilo.) This was 130% of the value o f the m o n o c r o p p e d maize. For the cropping pattern given in Table I, the following yields per ha per year can be e x p e c t e d in Indonesia (Beets and Brink, 1974.). Maize 0.7 metric tons/ha, rice 1.5 metric tons/ha, groundnuts 0.5 metric tons/ha, cassava 5 metric tons/ha. The total value of this produce at the local m arket price (maize 35 Rp/kg, rice 70 Rp/kg, groundnuts 85 Rp/kg, cassava Wlonocropping c~ 4 0 0 0

g

3 000

Mixed croppfng

21

o

2 ooo

c~

I 000 +-'- +-- +

40 000

+

53 333

÷

+

÷

+

÷~

66'600

~

Mixed cropping

80'000

Maize p o p u l a t i o n ( p l a n t s / h a )

Figure 4. Comparison of yields of monocropped maize and maize grown at 4 populations mixed with soya-beans planted at different dates. (--) Maize, same day of planting; ( I l I I ) Maize, planted 8 days later than soya-beans; (. . . . ) Soya-beans, same day of planting; (++++) Soya-beans planted 8 days ahead of maize.

27 058

14 819

12 868

50 0 0 5

Rice--rice

Rice--rice--vegetables

Rice--vegetables-rice--vegetables

Gross returns (A)

Rice--rice~oya-beans

Cropping p a t t e r n

585

1 443

1 001

474

8 727

8 545

6 401

5 251

P r o d u c t i o n costs Seed Fertilizers

11 867

10 4 3 3

7 835

6 457

Labour

3 543

2 846

2 243

2 391

Animal/ machinery

1 185

1 133

813

693

Pesticides

Net r e t u r n s f r o m m u l t i p l e c r o p p i n g in T a i w a n ( U n i t : N T S / h a / y e a r ; US $ I = N T $ 4 0 )

T A B L E II

165

233

289

172

Others

26 072

24 736

18 532

15 4 3 8

(B)

Total

23 9 3 3

18 132

16 287

11 620

Net returns (A B)

206.0

156.0

140.2

100.0

Index

b~ --3

228 10 R p / k g ) w o u l d be R p 2 2 2 000 p e r ha. (1 US $ = 415 Rp.). T h e average yield o f m a i z e in I n d o n e s i a is 0.9 m e t r i c t o n / h a . With the p r e s e n t s y s t e m , a p p r o x i m a t e l y 3 yields o f m o n o c r o p p e d m a i z e can be e x p e c t e d in 2 years. T h e r e t u r n o f this land is t h e n 1.35 m e t r i c t o n s o f maize, with a value o f 47 250 R p / h a per year. T h e o u t - p u t increase f r o m Rp. 47 2 5 0 to 222 0 0 0 is, o f course, n o t o n l y a result of the p r o p o s e d m u l t i p l e c r o p p i n g practice, b u t also o f b e t t e r fertilizer use and o t h e r i m p r o v e d practices. It s h o w s which i m p r o v e m e n t s can be o b t a i n e d b y relatively simple and n o n capital intensive measures. In T a i w a n , w h e r e v e r y s o p h i s t i c a t e d s y s t e m s o f m u l t i p l e c r o p p i n g were d e v e l o p e d , it has b e e n p r o v e d t h a t m u l t i p l e c r o p p i n g s y s t e m s have assured an a d e q u a t e increased r e t u r n t o p r o d u c e r s . T h e f o l l o w i n g table f r o m a " R e p o r t on E c o n o m i c S u r v e y o f L a n d Utilization a n d C r o p P r o d u c t i o n in T a i w a n " , 1965, p r o v e s this (see T a b l e II). Considering the t w o c r o p c o m b i n a t i o n s o f rice--rice a n d r i c e - - v e g e t a b l e s - rice--vegetables, o n e sees t h a t , while p r o d u c t i o n costs increased f r o m N T $ 1 5 4 3 8 t o N T $ 26 072 gross r e t u r n s increased f r o m N T $ 27 0 5 8 t o N T $ 50 005 and n e t r e t u r n s f r o m N T $ 1 1 6 2 0 to N T $ 23 933. In o t h e r w o r d s , costs p e r u n i t of land w e r e higher in t h e v e r y intensive s y s t e m , b u t gross r e t u r n s are even higher; while n e t r e t u r n s are also increased (84.8% and 106%, r e s p e c t i v e l y ) , costs increased b y o n l y 68%. L a b o u r , w h i c h is the highest single p r o d u c t i o n c o s t c o m p o n e n t increased b y 83.8%. H o w ever, if one assumes t h a t the w h o l e or m a j o r p a r t o f the l a b o u r is p r o v i d e d b y the f a r m f a m i l y , as is the n o r m a l case in T a i w a n , t h e cash o u t f l o w f o r l a b o u r w o u l d be v e r y low or nil. T h e i n t e n s i t y o f land use increased b y a p p r o x i m a t e l y 100%, a n d the aggregate n e t p r o f i t f o r the y e a r o b v i o u s l y e x c e e d s t h a t o b t a i n e d f r o m a n y single crop. REFERENCES Aiyer, A.K.Y.N., 1949. Mixed cropping in India. Indian J. Agric. Sci., pp. 439--543. Beets, W. and Brink, H., 1974. Final report FAO Fertilizer Programme East Java, Indonesia, (unpublished). Food and Fertilizer Technology Center for the Asian and Pacific Region, 1974. Multiple Cropping systems in Taiwan. Taipei, 78 pp. Indian Society of Agronomy, December 1973, Multiple Cropping. International Rice Research Institute (Los Banos) Annual report, 1973. Multiple Cropping. pp. 15--34. Kasetsart University, Department of Agriculture 1972 Annual Report, Corn and Sorghum Programme (Multiple Cropping). Ogunfowora, O. and Norman, D.W., 1974. An optimization model for evaluating the stability of sole cropping and mixed cropping systems under changing resource and technology levels. Semaru Res. Bull. (Ibadan, Nigeria), 11 p. Production Year Book, 1972. FAO, Rome, Vol. 26. Russell, E.W., 1961. Soil Conditions and Plant Growth. Longmans, London, pp. 545--550. Ward, R.G., 1965. Land Use and Population in Fiji. Overseas Research Publication, London.