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INCREASING WATER PRODUCTIVITY THROUGH APPLYINGTROPICAL PERENNIAL RICE CROPPING SYSTEM (SALIBUTECHNOLOGY) IN CDZ, MYANMARAUGMENTER LA PRODUCTIVITÉ DE L’EAU À TRAVERSL’APPLICATION TROPICALE VIVACE DE RIZICULTURE SYSTÈME(SALIBU TECHNOLOGY) DANS CDZ, MYANMAR
Kazumi Yamaoka1, Khin Mar Htay2, Erdiman3 and Resfa Fitri4

ABSTRACT
Rice is grown as a monocarpic annual plant. However, in tropical areas it can survive
as a perennial plant so that it can continue to produce ratoon crop grains over thegenerations. It is known that Japonica and Javanica in Oryza sativa subspecies has
stronger characteristics as a perennial plant than Indica in the same subspecies andAfrican varieties in the Oryza glaberrima species. Ratooning is a method of harvestinga crop which leaves the roots and the lower parts of the plant to grow the ratoon or the
stubble crop. Ratooning is regarded as an established farming system in some crops
like sugarcane, banana and sorghum with a reasonable yield while rice ratooning isregarded as just supplementary crop because of its low yield in general ranging 20 to
50% of its main crop.
The Central Dry Zone (CDZ) covers more than 54,000km 2, encompassing 58
townships and approximately 36% of Myanmar’s population. Dry spells during the rainyseason in CDZ are frequent, but their intensities vary geographically and over time.
Substantial amount of rice production is generated in irrigated paddy fields along theedges of CDZ. However, water use efficiency of the irrigated rice production remains
low and is expected to become worse along with in climate change. More rice crop per
drop water, i.e. increase of water productivity, is an essential issue of this region.
Tropical perennial rice cropping system (SALIBU technology) is suggested for solving
this issue.
This ratooning system developed in West Sumatra in Indonesia allows to harvest ricegrain 3.5 to 4 times annually and realizes a higher yield of ratoon crop as well as main
crop under the tropical or sub-tropical, winterless climate as well as the condition ofirrigable paddies throughout the year but lesser volume of water per one crop season
whether by surface or groundwater. The benefits of rice ratooning extend to not only
shortening the period for crop maturity but also saving various resources such as water,
labour, seed and topsoil as well as their associated costs owing to the omissible sowing
and land preparation and the shortened period for growing. This technology is not wellknown among scientists; however, the government of Indonesia has started a programto spread this farming system to all over the county since January 2017.

1 Senior Researcher, Japan International Research Center for Agricultural Sciences (JIRCAS), 1-1 Ohwashi,
Tsukuba, Ibaraki-ken, 305-8686 Japan, E-mail: kyamaoka@affrc.go.jp / kaz59@fmail.plala.or.jp
2 Deputy Director, Department of Agricultural Research (DAR), Ministry of Agriculture, Livestock and
Irrigation, Yezin, Naypyitaw, Myanmar, Email: khinmarhtay2007@gmail.com
3 Visiting Research Fellow, Faculty of Economics and Management, Bogor Agricultural University (IPB-FEM),
Jl. Kamper, IPB Dramage Campus, Bogor, West Java, Indonesia, Email: erdimantanjung@gmail.com
4 Lecturer, Faculty of Economics and Management, Bogor Agricultural University, Jl. Kamper, IPB Dramage
Campus, Bogor, West Java, Indonesia, Email: rfitri2@gmail.com

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`JIRCAS, DAR in Myanmar and IPB-FEM in Indonesia have started a researchcollaboration on “Improvement of irrigation water productivity for paddy rice production
by means of SALIBU ratoon technology in CDZ, Myanmar.” A preliminary study under
the pot cultivation proved that a popular local variety namely Thee Htat Yin performedin yield 9.1 t/ha by ratoon crop while 5.3 t/ha by main crop. It also shows that the ratoon
scores much higher number of tillers, panicle per hill and biomass weight than main
crop while the number of spikelet per panicle, weight of 1000 grains and percentage offilled grains are lower.
The research project has released field experiments in the test fields of DAR for more
precise study on the Tropical Perennial Rice cropping system and its water productivity.
This system may contribute to realizing a New Green Revolution in terms of bothincreasing production and saving global resources.
Keywords: Ratoon Crop, Perennial Rice, Field Capacity, Water Productivity, Triangle
Research Cooperation

RÉSUMÉ ET CONCLUSIONS
Le riz est cultivé comme plante annuelle monocarpique. Toutefois, dans les régions
tropicales il peut survivre comme une plante vivace, afin qu’elle puisse continuer à
produire des céréales de culture de repousses au fil des générations. On sait que
Japonica et Javanica chez Oryza sativa sous-espèce possède des caractéristiques
plus forts comme une plante vivace que Indica de la même sous-espèce et variétésafricaines dans les espèces du genre Oryza glaberrima. Coupes successives est une
méthode de récolte d’une culture qui laisse les racines et les parties inférieures de laplante de croître les repousses ou que la récolte de chaume. Coupes successives est
considéré comme un système d’agriculture établie dans certaines cultures comme lacanne à sucre, banane et le sorgho avec un rendement raisonnable, tandis que le riz
coupes successives est considéré comme une récolte supplémentaire juste à causede son faible rendement en général allant de 20 à 50 % de sa récolte principale.
La Zone sèche centrale (CDZ) couvre plus de 54 000 km 2, englobant des 58 cantons
et environ 36 % de la population du Myanmar. Des périodes de sécheresse au coursde la saison des pluies en CDZ sont fréquentes, mais leurs intensités varient dans letemps et géographiquement. Une quantité substantielle de la production de riz est
générée dans les rizières irriguées le long des bords des CDZ. Toutefois, de l’efficacitéde la production de riz irrigué reste faible et devrait s’aggraver le long avec dans lechangement climatique. Plus de riz récolte par goutte d’eau, c'est-à-dire augmentationde la productivité de l’eau, est un point essentiel de cette région. Tropicale vivace
riziculture de système (Sassi technology) est suggérée pour résoudre cette question.
Ce système bien développé dans l’ouest de Sumatra en Indonésie permet de récolter
du grain de riz 3.5 à 4 fois par an et réalise un rendement supérieur de repousses
comme culture principale sous le tropical ou subtropical, climat winterless ainsi quel’état des rizières irrigables tout au long de l’année, mais moins de volume d’eau parune saison de récolte, que ce soit en surface ou souterraines. Les avantages du riz
coupes successives vont non seulement raccourcir la période de maturité des culturesmais aussi sauver diverses ressources comme l’eau, du travail, semences et terre
végétale ainsi que les coûts y afférents en raison de la préparation facultatifs de semis
et de la terre et la période raccourcie pour la culture. Cette technologie n’est pas bien
connue chez les scientifiques, cependant, le gouvernement indonésien a commencé
un programme visant à répandre ce système d’élevage à travers le comté depuis
janvier 2017.
JIRCAS, DAR au Myanmar et IPB-FEM en Indonésie ont commencé une collaborationde recherche sur « L’amélioration de la productivité de l’eau d’irrigation pour la2

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production de riz paddy au moyen de la technologie de repousses Sassi dans CDZ,
Myanmar. » Une étude préliminaire en vertu de la culture de pot s’est avéré qu’unevariété populaire locale à savoir Thee Htat Yin interprété avec un rendement 9.1 t/ha
par repousses tandis que 5,3 t/ha en culture principale. Il montre aussi que les scoresde repousses beaucoup plus grand nombre de talles, panicule par hill et la biomassede poids que la culture principale tandis que le nombre d’épillets par panicule, poidsde 1000 grains et le pourcentage de grains remplis sont plus faibles.
Le projet de recherche a publié des expériences sur le terrain dans les domaines del’essai de DAR pour une étude plus précise sur la tropicale vivace riziculture systèmeet la productivité de l’eau. Ce système peut contribuer à la réalisation d’une nouvellerévolution verte en termes d’augmentation de la production et économie desressources mondiales.
Mots clés: Repousses Crop, riz vivace, capacité au champ, la productivité de l’eau,
Triangle recherche coopération

1.

Introduction

Rice is one of the world’s three major crops, cultivated in 162.3 million hectares,
produced for 738.1 million tons as paddy, and grown as a monocarpic annual plant.
Production and consumption of rice is dominated in Asia; however, rice becomes more
popular in the rest of the world recently and especially the consumption (domestic
supply) of rice in Sub-Saharan Africa has drastically increased in the last decade (20032013) by 9.8 million ton while its domestic production has done by 6.8 million ton. Many
counties in this region are boosting the domestic rice production as one of major
national economic issues because the rapid increase of the gap between domestic
production and consumption, i.e. import of rice from Asian countries, forces thecountries spend the precious foreign currency wastefully. Rice is believed to be a
promising food crop to feed the next generation.
To achieve the target 2.1 of Sustainable Development Goals, describing that by 2030
end hunger and ensure access by all people, in particular the poor and people invulnerable situations…, we must concentrate our efforts on Sub-Saharan Africa andSouth Asia where the target of eradication of hunger in Millennium Development Goals
was not attained. FAO’s report “How to Feed the World in 2050” said in 2009 that by
2050 the world’s population will reach 9.1 billion, 34 percent higher than today and foodproduction (without food used for biofuels) must increase by 70 percent due toaccelerated urbanization and higher income level of people. FAO also expects that
globally 90 percent (80 percent in developing countries) of the growth in crop production
will come from intensification, in particular higher yields and increased cropping
intensity. It means that in developing country only 20 percent will come from expansionof arable land but the rate of growth in yields of the major cereal crops in the world has
been steadily declining, it dropped from 3.2 percent per year in 1960 to 1.5 percent in2000. The challenge for technology is to reverse this decline at a global level.
On the other hand, agricultural production and distribution of food has been a major
contributor to greenhouse gas emissions. The large increase in the use of nitrogen
fertilizer to produce crops like corn, while it has happened hand in hand with Green
Revolution since 1940’s, has dramatically increased the emissions of nitrous oxide, apowerful greenhouse gas. The gasoline and diesel fuel that is consumed by tractors
and trucks is also a large source of carbon dioxide emissions. Additionally, resources
such as land, water, fossil oil and minerals available in the world are limited. We needmuch more food production in the future but at the same time we must reduce in using
various resources relating the food production in terms of saving both carbon emission
and use of resources.

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And note that hunger can persist in the midst of adequate aggregate supplies becauseof lacking income opportunities for the poor and the absence of effective social safety
nets. Growth originating in agriculture, in particular the smallholder sector, is at least
twice as effective in benefiting the poorest as growth from non-agriculture sectors. The
report said that this is not surprising since 75 percent of the poor in developing countries
live in rural areas and their incomes are directly or indirectly linked to agriculture. The
fight against hunger also requires targeted and deliberate action. Increase of theincome of farmers, especially small holders, should be directly targeted to achieve thesecond goal of SDGs, i.e. “End hunger.”
This report also argues that the required increase in food production can be achieved
if the necessary investment is undertaken and policies conducive to agricultural
production are put in place. The required increase in developing countries is about 50
percent over current investment levels. These figures are totals for public and private
investment, i.e. investments by farmers. So, it is essential for us to increase the incomeof farmers, even poor small holders, to ensure their investment for more foodproduction.
We must tackle with the multi-faceted challenges such as for technology to increase inyields, for saving both carbon emission and use of resources, and for directly increasing
income of small holder farmers in terms of both ending hunger and ensuring theirinvestment.

2.

Review of Studies on Rice Ratooning

Rice is cultivated as a monocarpic annual plant in conventional farming systems.
However, in fact, in tropical areas it can survive as a perennial plant so that it cancontinue to produce ratoon crop grains over the generations. It is known that Japonica
and Javanica in Oryza sativa subspecies has stronger characteristics as a perennial
plant than Indica in the same subspecies and African varieties in the Oryza glaberrima
species (Sakagami et al., 1999a and 1999b). Ratooning is a method of harvesting acrop which leaves the roots and the lower parts of the plant to grow the ratoon or the
stubble crop. Ratooning is regarded as an established farming system in some crops
like sugarcane, banana and sorghum with a reasonable yield while rice ratooning isregarded as just supplementary crop because of its low yield in general ranging 20 to
50% of its main crop (Krishnamurthy, 1988).
Rice ratooning has often been a subject of researches since 1950’s and been analysedfrom various aspects such as morphology, physiology, ratoon development earliness,varietal potentiality, capacity of making tillers, growth duration of main crop, plant height,
land preparation and spacing for main crop, timing of harvest of main crop, cuttingheight of the stubble, fertilizer management, water management, temperature and lightintensity. The authors had made excerpts of F.C.Oad et al. (2002) reviewed well onrice ratooning, as follows.
2.1

Morphology, physiology and ratoon development earlinessOad et al. (2002) said such as, "Usually plant height (Balasubramanian et al., 1970) is
lower and effective tillers are fewer in the ratoon crop than the main crop (Bahar and
De Datta, 1977). Stem thickness is correlated with higher carbohydrate content in the
stubbles, which results in more vigorous regeneration of ratoon tillers and grain yield(Palchamy and Purushothaman, 1988). Cultivars and practices, including cutting height
and fertilizer management, which provide a large quantity of reserves at harvest, may
be advantageous for rice ratooning (Ichii, 1984). High cutting of main crop stubbles
helps increase of the amount of Total Carbohydrate Content (TAC) in the stubbles andratoon growth of rice depends upon the amount of TAC in the stem base, which results
in producing many tillers (Ichii and Ogaya, 1985). Several studies showed that ratoon
tiller development depends upon the carbohydrates that remain in the stubbles and4

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root after the main crop is harvested (Cuevas Perez, 1980; Ichii and Sumi, 1983; andSamson, 1980).” It implies that cultivation trials using Carbon tracer with different
cutting heights for ratooning may be useful.
And said such as, "The ratoon tiller regeneration and growth depends on the buds thatremained on the stubbles and exist in various stages of development (Nair and
Sahadevan, 1961). In Kagi Ban2 cultivar, the C:N ratio was 17.0 in tillers from upper
nodes, 13.88 in those from the base and 10.80 from those below the soil, and the tillers
from the upper nodes with high C:N matured faster like old seedlings and were shorterin culm than those tillers emerging from the lower nodes which behaved like young
seedlings (Iso, 1954). Early tiller regeneration may encourage tillering by providing
nutrients to the developing buds (Chauhan et al., 1985).” It implies that the relation
between the growth speed of ratoon tiller and the node of which the tiller regenerates
must be studied precisely.
2.2

Varietal potentiality, tillering capacity and main crop growth duration

Oad et al. (2002) said such as, "The prospect of successful ratoon cultivation depends
largely on ratooning of a variety. Ratooning ability has been found to be a varietal
character (Bahar, 1976, Balasubramanian et al., 1970, Bahar and De Datta, 1977;
Haque, 1975; Nadal and Carangal, 1979). Further, Nadal and Carangal (1979)
identified three rice selections without standing tillering capacities and high ratoon
yields under varying soil moisture regimes. Haque (1975) found out that IR2061- U23,
IR2145-20-4 and IR1924-36-22 possessed high ratooning ability. In India, C3810,
Ratna, CR20-66, and CR156-5021-207 showed superiority in ratooning and yield ability(Das and Ahmed, 1982). The hybrid Zaishelgyou produced the highest main and ratoon
crop yields resulting in a significantly higher total yield (11.0 t/ha).” It implies that the
ratooning performance depends largely on varieties.
And said such as, "Tillering ability is probably the most important genetic factor affecting
ratoon performance of grasses. In ratoon crop the effective tillers are fewer comparedto the main crop, however, the actual number of tillers may be higher in the ratoon cropthan in the main crop (Balusubramanian et al., 1970). Varietal differences exist withrespect to emergence of ratoon tillers from different nodes of the stubbles. The tillers
may emerge from all nodes of the stubbles or from only the lower nodes or from any
specific node number. Many findings suggested that ratoon crop is better if the main
crop stubble is cut with 2-3 nodes left.” It implies that the difference of variety may
strongly affect tillering ability and the node number from which the tillers emerge
resulting in ratooning performance.
And said such as, "Main crop growth duration has been reported to influence ratooning
ability (Bardhan Roy et al., 1982; Cuevas Perez, 1980) Growth duration and grain yield
was correlated strongly. Varieties with longer growth duration tended to have stronger
ratooning ability. However, very early maturing cultivars were recommended for ratoon
crops in temperate areas because they do not require early seeding and allow afavourable growth period for the ratoon crop. Zandstra and Samson (1979) foundsignificant correlation between ratoon crop yield and ratoon crop duration (r = 0.71) andbetween ratoon crop duration and main crop duration (r = 0.65).” It implies that
prolonging ratoon crop duration may become a key technology for its high yield.
2.3

Timing of harvest of main crop and cutting height of the stubble

Oad et al. (2002) said such as, "The best time to harvest the main crop for raising agood ratoon crop is when culms are still green (Parago, 1963b). The best time toharvest the main crop for maximum ratoon yield is before the crop is fully matured(Nagai, 1958; Balsubramanian et al., 1970). Optimum cutting height should be 30-40
cm above grounds (Zhang Jing Guo, 1991). Haque, (1975) and Reddy et al., (1979)
proposed that harvesting at 30, 35, 40, and 45 days after main crop flowering did not5

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significantly affect ratoon yields, however, Mahadevppa et al., (1988) mentioned that
because senescence is a varietal character, the time of main crop harvest might
depend upon the variety and location.” It implies that harvest of main crop in the timingof physiological maturity when its roots and stems are still vital is better for ratooning.
And said such as, "Cutting height determines the origin of the ratoon tiller and growthduration of ratoon crop (Sun Xiaohui et al., 1988). The effect of cutting height on ratoon
vigour varied. Some cultivars ratooned from high node, others produced basal ratoon
that are unaffected by cutting height (Volkova and Smetanin, 1971). Bardhan Roy andMondal (1982) reported that cutting height did not significantly affect ratooning ability,
reproductive tillers and ratoon yields. In the Philippines ground level cutting was
suggested to prevent growth of unproductive tillers (Parago, 1963). It was reported thatin the Philippines wet season rain fall is heavy, and cutting close to the ground level
may risk a high tiller mortality rate and poor ratoon crop stand density (Zandstra andSamson, 1979; Samson, 1980; Chauhan et al., 1985). In Cambodia, plant cut at
15 cm gave higher yields than plants cut at ground level (Szokolay, 1956). However,Iso (1954) recommended that main crop cutting should leave 1.25 cm of the stubble
above the water level. Submerged stubble may rot and tall stubbles may put forth vary
weak tillers. Andrade et al., (1985) evaluated 10 irrigated rice cultivars at 10, 20 and 30
cm cutting heights. They observed that 30 cm cutting height gave the best results
including plant height in all cultivars. Hsieh et al., (1959) recorded a rate of tillering of
89.1, 80.6 and 71.9% at 24, 15 and 6 cm cutting height respectively. Reddy and Pawar(1959) conducted studies at Karnataka and noted that cuttings 8, 13 and 18 cm did notaffect ratoon yields. In Japan ratoon stand varied with cutting height but these did notaffect grain yield (Ishikawa, 1964).” It implies that the relations between cutting height
and the node number emerging tillers, ratooning ability, number of effective tillers andyield of ratoon crop are varied. However, those studies did not apply two steps cutting
but only once and maintain stems of stubbles as cut until harvest.
2.4

Water management and fertilizer management

Oad et al. (2002) said such as, "Water management before and after main crop harvest
affected ratooning ability (Votong, 1975; Hague, 1975). To promote ratooning, the fieldshould be moist but not flooded for weeks at the end of the main crop ripening. Draining
the field several days after harvest also encourages ratooning. Irrigation water must be
kept shallow in the early ratooning stages. It is essential to have irrigation immediately
after the first fertilizer application. Fields drained during harvest of the main crop to
promote tillering of ground level cuttings had more weeds. Furthermore, ground level
cutting with continuous 5-7 cm flooding produced very few ratoons and increased
percentage of missing hills. Such a problem was not observed with 15 cm or higher
cutting height (Bahar and De Datta, 1977). Ichii (1983) reported that water management
did not affect percentage of ratoon tillers or a ratoon height irrespective of height of
cutting. Draining the main crop at harvest is generally suggested to promote ratooning
and prevent death of hills due to flooding. However, under rain fed situation wherewater must be retained as much as possible, the main crop should be cut at 15 cm
higher to reduce the number of missing hills in the ratoon crop (Zandstra and Samson,1979). If flooded water is not maintained, main crop grain that fell to the ground during
mechanical harvest will germinate and compete with the ratoon crop for light andnutrients (Mengal and Wilson, 1981). Many hills died when the crop was cut at groundlevel and water remained 5 cm deep (Ichii and Ogaya, 1985).” It implies that watercondition in several key stages of growth of main crop and ratoon crop is crucially
important such as; irrigation for main crop and ratoon crop is necessary in general andkeeping soil moisture without flooded water in some period before and after its harvest
is highly recommended, however, it brings more weeding works and the stubbles withvery short length submerged by flooded water may cause more missing hills.
And said such as, "Soil fertility may directly or indirectly affect ratoon crop growth andyield (Plucknett et al., 1978). At IRRI, Philippines grain yield significantly increased as6

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N rate increased. N level was optimal at 60 kg/ha (Bahar and De Datta, 1977). Postharvest nitrogen application to main crop consistently increased ratoon crop yield.
Besides amount of applied N, application method in the main crops affects the ratoon
crop (Quddus, 1981; Samson, 1980). Palchamy and Purushothaman (1988) reported
that N split application at maximum tillering and at panicle initiation increased the ratoon
crop grain yield up to 86.6% of the main crop. Lack of acceptance of rice ratooning bycommercial farmers has been attributed to low yields, lack of good ratooning varieties,
uneven maturity, disease and insect problem, lack of location-specific cultural practices,
inferior grain quality and lack of assured return from investment (Chauhan et al., 1985).”
It implies that fertilization to both main crop and ratoon crop is important for a higher
yield of ratoon crop and rice ratooning for commercial farming is a big challenge.

3.

An Encounter with New Rice Ratoon Cropping System

There are so many arguments on rice ratoon crop but no article affirmed that the yieldof rice ratoon crop could be equivalent to or more than that of main crop. Lower yieldof rice ratoon crop has been a common sense and brought researchers to haveassumption that perennial cultivation of rice must be a useless attempt. So, rice ratoon
crop has always been treated as one-generation supplementary crop with nosuccessors. The common sense and assumption also have made researchers ignore
the study on saving irrigation water for rice ratoon cropping system while farmers may
reduce their use of irrigation water because the ratooning makes shorter period of
cultivation and omissible water use for seedling nursery, puddling and transplanting.
On the contrary, the new rice ratoon cropping system with special stubble treatment
developed in West Sumatra in Indonesia, namely Tropical Perennial Rice Cropping
System (SALIBU technology), allows to harvest rice grain 3.5 to 4 times annually andrealizes an equivalent or a higher yield of ratoon crop grain than main crop under thetropical or sub-tropical, winterless climate. It requires the condition of irrigable paddies
throughout the year as well but lesser volume of water per one crop season whether
by surface or groundwater. Introduction of this technology to rice farming small holders
must allow to solve the multi-faceted challenges described in “1. Introduction.” Thebenefits of rice ratooning extend to not only shortening the period for crop maturity andallowing farmers to harvest and sell more annually but also saving various resources
such as water, labour, seed and topsoil as well as their associated costs owing to theomissible sowing and land preparation and the shortened period for growing. This
technology is not well known among scientists; however, the government of Indonesia
has started a program to spread this farming system to 10,000 ha of paddy fields allover the county since January 2017.
In January 2014, chance brought the first author of this paper to visit the rice paddy
fields under the SALIBU technology and to meet Mr. Erdiman who was the inventor ofthis technology. The visit to Tanah Datar sub-district in West Sumatra province was apart of the author’s field survey on WUAs (Water Users’ Associations) and theirperformances because the author was an expert on irrigation and water resourcesmanagement. The author made interviews to village people and Mr. Erdiman explainedof the essence of this technology. The author was greatly interested in the focus of his
attention and the mechanisms of increasing yield of ratoon crop grain. The wonder wasthat farmers, mostly women, actually enjoyed the technology and made a success of
ratoon rice cultivation under this technology. The author felt then the great potential ofthis technology’s impacts on our future society but at the same time supposed that
other scientists such as agronomists must put this technology out into the world.
In June 2016, two years and half after the visit to Tanah Datar, the author discovered
the SALIBU technology was still in the position of a local technology and not yet wellintroduced to researchers nor overseas.

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4.

Collaborative Research Plan

The Central Dry Zone (CDZ) covers more than 54,000km 2, encompassing 58
townships and approximately 36% of Myanmar’s population. Dry spells during the rainyseason in CDZ are frequent, but their intensities vary geographically and over time.
Substantial amount of rice production is generated in irrigated paddy fields along theedges of CDZ. However, water use efficiency of the irrigated rice production remains
low and is expected to become worse along with in climate change. More rice crop per
drop water, i.e. increase of water productivity, is an essential issue of this region.
The author believes that the Tropical Perennial Rice Cropping System (SALIBU
technology) must solve this issue because farmers can reduce their use of irrigationwater per harvest under this system. First, this system makes the period of cultivation
shorter by 20-35 days (from 120-140 days in conventional to 90-105 days under
SALIBU technology), and it doesn’t require the irrigation water for puddling andtransplanting. It means the increase of water productivity. We should identify suitable
rice species for this technology and develop a cropping system under the climate, soil,
water and labour conditions in CDZ. In this regard JIRCAS (Japan International
Research Center for Agricultural Sciences), DAR (Department of Agricultural Research,
Ministry of Agriculture, Livestock and Irrigation) in Myanmar and IPB-FEM (Faculty of
Economy and Management, Bogor Agricultural University) in Indonesia have started a
research collaboration on “Improvement of irrigation water productivity for paddy riceproduction by means of SALIBU ratoon technology in CDZ, Myanmar” since 2016
under the JIRCAS’s research project on “Development of Agricultural Technologies for
Reducing Greenhouse Gas Emissions and Climate-related Risks in Developing
Countries.”
Objectives of the research collaboration are to verify improvement of irrigation waterproductivity for paddy rice production to cope with the impact of climate change bymeans of SALIBU ratoon technology in CDZ, Myanmar. The suggested research planis given in Table1.
Table 1. Collaborative Research Plan (2016-2020)
Year
2016
2017

2018

2019

2020

Annual plan
Collecting basic data on irrigated paddy rice production and preparing forpreliminary demonstration of SALIBU ratoon technology in test fields
Equipping water measures for data collection in test fields and carrying out
the first experimental study on improving irrigation water productivity forpaddy rice production by means of SALIBU ratoon technology
Elucidating general trend on the balance of between effects of SALIBU ratoon
technology for increasing production and saving irrigation water use throughpreliminarily comparative studies in test fields
Elucidating precise characteristics on the balance of between effects of
SALIBU ratoon technology for increasing production and saving irrigationwater use through fully comparative studies in test fields and drafting amanual for adopting technology
Verifying the contents of the manual on improvement of irrigation waterproductivity for paddy rice production by means of SALIBU ratoon technology
in farmers’ fields and modifying the manual for its finalization

5.

Design of Study and Results of Preliminary Tests

5.1

Tropical perennial rice cropping system (SALIBU technology)

SALIBU technology was progressively developed since 2007 when Mr. Erdiman, whois the inventor of the technology, visited Matur village located in a suburb of Bukittinggi,

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West Sumatra. His wife had been born in this village and he was a staff of West
Sumatra office, Assessment Institute for Agricultural Technology (BPTP), Indonesia atthat time. The village is in an elevation of 1,100 meters and the high-altitude brings acool climate for its equatorial topography. Rice ratoon crop farming was traditionallycommon here because farmers planted only two cold-tolerant varieties, i.e. Kurik
Kusuik and Lumut Kurik Kusuik, which needed about 145 days from sowing toharvesting and they wanted to have another earlier opportunity of harvest by ratoon
crop to secure foods in case of a poor harvest.
The farmers had been adopting a rice ratoon crop farming practise recommended by
IRRI (International Rice Research Institute), which required cutting rice stubbles at 1520 cm height above ground surface. However, they had two complains about thisfarming practise; i) Ununiformed maturity forcing them to harvest the rice twice or threetimes, and ii) Badly low yield compared to main crop. They asked Mr. Erdiman to solvethese problems and he found a solution in 2010 after repeated observation and trial
and error to ratoon crop; he got an inspiration and conceived an idea of cutting the rice
stubbles at the lowest height above ground surface and keeping soil moisture in thefield capacity condition. His trial made much better results on the both problems thanthe practise recommended by IRRI. He named the new rice ratoon crop farming system
as SALIBU technology because the local farmers called ratoon SALIBU. He continued
the growing tests on rice ratoon crop and the extension of the technology to farmers inMatur and in Parabek village located in 5km away from Bukittinggi.
He must bear the cost for the test and the extension to farmers because Research andDevelopment Department, Ministry of Agriculture, Indonesia terminated the budget forrice ratoon research by 2010. However, in 2012 West Sumatra office, BPTP
acknowledged SALIBU technology as a new technology to support its development
and appropriated a budget for it while other offices of BPTP didn’t. He stayed in a hotel
nearby villages during critical periods while he went by car from his house in Padang
to the villages.
The recommended procedure of Tropical perennial rice cropping system is given in
Table 2 including a rotational 10 steps.
Table 2. Recommended Procedure of Tropical perennial rice cropping system (SALIBU
technology)
No
1
2
3

4

5
6
7
8
9

Cultivation techniques
Carefully levelling paddy fields for main crop and transplanting seedlings in a
locally conventional way or Indonesian “Legowo” system is recommended
Fertilizing an a locally conventional way but additionally the 1st fertilizing for
ratooning 7-14 days before harvest
Stopping irrigation 14 days before harvesting, and keeping the soil moisture infield capacity condition (humid as much as possible) until 14 days after
harvesting to stimulate the growth of buds and tillers
Harvesting the main crop 7 days earlier than conventional harvest timing, under
the physiological maturity not harvest maturity, to keep the lower part of
stubbles fresh for vital ratooning
If the soil becomes too dry, flooding for 1-2 days, then draining until the soil ishumid.
Cutting-off lower part of stubbles 7 days after harvesting at 3-5 cm height above
ground surface
Starting shallow irrigation when the height of tillers reached 5-7 cm
Moving (separation and addition) of part of stubbles, inserting floating stubbles
into the soil, the first weeding and the 2nd fertilizing 15-22 days after cutting-off
Stopping irrigation 29 days after cutting-off, and keeping the soil moisture infield capacity condition (humid) for 15 days

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10
11
12
13

Resuming irrigation 44 days after cutting-off
The 3rd fertilizing and the 2nd weeding 44-49 days after cutting-off
The 1st fertilizing for ratooning 7-14 days before harvest
Repeating steps from 3 to 12 (rotational 10 steps) for next generations of
SALIBU ratoon crop

The procedure is a prototype and to be appropriately modified per variety, soil type andclimate condition. The most critical steps are 3, 4 and 6 followed by 8, 11 and 12. Notethat in 8th step “moving” means digging a small number of tillers with roots in a larger
stubble out of soil by hand and replanting it to a poor stubble to avoid unevenness ofgrowth, and “inserting” means pushing tillers and roots sprouted from a higher node
into the soil by toe to avoid naked roots in the air. The cutting-off is always done bypower grass mower. Knapsack power mowers with two blades are recommended.
5.2

Application of SALIBU technology to test fields in DAR

A comparative study onrice ratooning is designed
Legendas Figure 1 and the
ratooning is conducted
Salibuper the procedure aboveIRRI
mentioned with variety
Manawthukha. Figure 2
Conventional
shows
more
specificmanual for the cultivation
Ｌ２ Legowo 2:1
of main and ratoon crop.
Sowing was done on 7
Ｌ４ Legowo 4:1
January, 2017 and seedC Conventionallings were transplanted on
30 January, 2017 to theOuter Levee
test field allocated in DAR.
Inner Levee
The study compares; a)
SALIBU ratooning, b)
0.5m wide gap
Ratooning with cutting off
the stubbles at 25cm
height above ground Figure 1. Field design for comparative study on ratooning
surface (IRRI), and c)
Non-ratooning conventional transplanting (control). It also compares; d) Indonesian
Legowo 2:1 system for transplanting, e) Legowo 4:1 system, and f) Locally conventionaltransplanting.
The collaborative research project has decided to conduct field experiments in the test
fields of DAR for more precise study on this technology and its water productivity.
Another comparative study is designed as Figure 3 to compare water productivity
between a) SALIBU ratooning with recommended water management, SALIBU
ratooning with AWD, and c) Non-ratooning conventional transplanting (control). It also
compares water productivity between varieties. Sowing and transplanting will be donein July, 2017.
Besides these field studies a preliminary study under the open-air pot (8ft x 6ft)
cultivation proved that a popular local variety in CDZ namely Thee Htat Yin performedin yield 9.1 t/ha by ratoon crop while 5.3 t/ha by main crop under the tropical perennial
rice cropping system (SALIBU technology) as given in Table 3. The main crop was
harvested on 11 November 2016 and cut off stubbles on 17 November, 2016 for
SALIBU ratooning. The 1st generation of SALIBU ratoon crop was harvested on 22
February, 2017, 103 days after the harvest of main crop. It showed that the ratoon
scores much higher number of tillers, panicle per hill and biomass weight than main10

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23rd International Congress on Irrigation and Drainage
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Variety: Manawthukha
0

SowingN--P62.5-125(kg/ha)K-- (--)

2nd Fertilizing for Main Crop

N
50

P
--

K
21 (31)

3rd Fertilizing for Main Crop

N
50

P
--

K
21 (31)

flowering

4th Fertilizing for Main Crop
Flowering

N
25

P
--

K
21 (--)

7-14BH

1st Fertilizing for SALIBU1Main crop (Mother plant)

23
23AS

Transplanting
10-14

10-14AT15
25-30AT
Just before

7-14
7BC
0
7
7AC

8

15AC

29AC

7

= Cutting for SALIBU1 (3-5 cm above the ground surface)
Starting irrigation (2-3 cm in depth)2) Inserting 3) WeedingN404) 2nd Fertilizing for SALIBU1

P
31-62.5

Keep the soil moisture in the field capacity condition

5

Starting irrigation (5-10 cm in depth)N
3rd Fertilizing for SALIBU160
2nd Weeding

49AC
7-14BHK
26

Stopping irrigation

15
44AC

P
--

K
36

N
P
K
25
31-62.5-Keep the soil moisture in the field capacity condition
1st Fertilizing for SALIBU2

7-14
7BC

Harvesting for SALIBU2 (Physiological maturity)
70

N: Nitrogen
P: Phosphate
K: Potassium
AS: After Sowing
AT: After Transplanting
BH: Before Harvest
BC: Before Cutting
AC: After Cutting

Timing for normal harvesting (Harvest maturity)

1) Moving
7

22AC

N
P
K
25
31-62.5-Keep the soil moisture in the field capacity condition

Note

Harvesting for SALIBU1 (Physiological maturity)
7

SALIBU (1st generation)

1st Fertilizing for Main Crop

Timing for normal harvesting (Harvest maturity)= Cutting for SALIBU2 (3-5 cm above the ground surface)

Figure 2. Manual for cultivation of main and ratoon crop
crop while the number of
spikelet per panicle, weight of1000 grains and percentage offilled grains are lower.
The 2nd generation of SALIBU
ratoon crop was harvested inearly June 2017. It is also
around 103 days after the
harvest of the 1st generation of
SALIBU ratoon crop. The
preliminary test results were
given in Table 4. Those
preliminary tests in DAR,
Myanmar show that the yields of
SALIBU ratoon crop are higher
than that of main crop and theduration of growth of SALIBU
ratoon crop are shorter than thatof main crop by about 10 days.

LegendW1: SALIBU
W2: SAIBU+AWD
W3: Conventional
V1: Variety 1
V2: Variety 2
V3: Variety 3

Figure 3. Test design for comparative study onwater productivity11

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23rd International Congress on Irrigation and Drainage
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Table 3. Preliminary test results of open-air pot (8ft x 6ft) cultivation (Main crop and 1st
generation of SALIBU ratoon crop)
Item
Date of sowing
Date of transplanting
Date of flowering
Date of harvesting
Plant height (cm)
Panicle length (cm)
No. of effective tillers
No. of Spikelet / panicle
No. of panicle / hill
1000 grain weight (g)Fill grain (%)
Biomass weight / hill (g)Harvest index
Yield (t/ha)

Main crop
19 Jul. 2016
9 Aug. 2016
5 Oct. 2016
11 Nov. 2016
92.70
22.95
10.00
126.94
9.78
21.68
81.94
22.41
0.49
5.28

SALIBU 1st generation(Cutting) 17 Nov. 201620 Jan. 201722 Feb 2017
68.20
19.89
38.60
92.37
36.00
18.92
60.15
73.74
0.51
9.09

Table 4. Preliminary test results of open-air pot (8ft x 6ft) cultivation (2nd generation of
SALIBU ratoon crop)Item
Pl. height (cm)Pa. length (cm)
Effective tillers
Spikelet / panicle
Panicle / hill
1000 grain weight (g)Fill grain (%)
Biomass wt. / hill (g)Harvest index
Yield (t/ha)

Plot1
88.00
26.70
22.00
100.00
22.00
19.00
77.90
82.80
0.55
10.78

Plot2
94.00
23.10
12.00
83.00
12.00
21.00
65.00
40.70
0.48
4.69

Plot3
103.00
25.50
15.00
73.00
15.00
20.30
58.60
40.70
0.47
4.49

Plot4
99.00
25.90
15.00
115.00
15.99
19.60
70.40
51.60
0.60
7.37

Plot5
75.00
18.20
40.00
86.00
40.00
19.00
65.79
76.70
0.35
8.36

Ave.
91.80
23.88
20.80
91.40
20.80
19.78
67.56
58.50
0.49
6.74

Figure 4. A preliminary study for the 2nd generation of SALIBU under
the pot cultivation with the local variety namely Thee Htat Yin
The site for demonstration of rice ratooning cultivation in various stages under thistechnology has also been developed in DAR. This is a preparation work for rapid
extension activity of the technology to farmers. Another possibility of this technology is
proposed by scientists in DAR. They want to apply the new rice ratooning system tothe seed propagation. The system may allow the conditions for producing more purified
seed in a simpler field settings.

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6.

Field Survey in West Sumatra Province

The authors of this paper together with Dean and professors in IPB-FEM visited Tabek,
Pariangan, and Tigo Bahea, Sungai, Tarab in Tanah Datar sub-district in West Sumatra
province and made an interview to farmers in the villages on 20 and 21 May 2017. The
first author collected following information through the interview to the leader of a
farmers’ group in Tabek, Pariangan;• 460 farmers organize 14 groups in the village on the land basis• Women organize 7 women farmers’ groups• SALIBU technology is applied by 100% of farmers of the village• His group consist of 52 farmers, and men/women is about 50:50• Women are engaged in transplanting, weeding, fertilizing and post-harvest
processing• Men are engaged in land preparation, paddling and levelling, cleaning ditches,
harvesting, and cutting off (trimming) for SALIBU ratooning• Water management is done by each land owner• Free charge of irrigation and no water shortage all the year around• Ratoon cropping was started in 2006 and SALIBU technology in 2011
The leader felt after introducing SALIBU technology in 2011;• Water consumption was reduced• Labours and carefulness for water management were maintained• Land levelling should be more carefully than conventional• Market price of SALIBU rice has been same as conventional one• Yield per acre was slightly increased (6t/ha → 7-8t/ha)• Total annual costs were reduced
They had already enjoyed almost same yield in ratoon rice cultivation as main crop
since 2006, however, they were not satisfied because;• Cutting off was manual, done by hand
• Uneven growth between shoots forced them harvest twice for the same plant
The first author also discovered through the interview in Tigo Bahea, Sungai, Tarabthat there were different stages of growth of paddy rice among farmers in a village aswell as there were different stages of that among plots of one farmer. The former may
contribute to diversification of risk of pest and disease and the latter must contribute toincrease the opportunity of income. And group activity such as harvest are maintainedin the village. So, each farmer of the village can get cash income around 8 times in ayear and enjoy more dispersive group activities. This increase of opportunity of income
and the increase of annual income must strongly encourage farmers to invest more tofarming.

7.

Conclusion and recommendations

The new rice ratoon cropping system with special stubble treatment developed in West
Sumatra in Indonesia, namely Tropical Perennial Rice Cropping System (SALIBU
technology), allows to harvest rice grain 3.5 to 4 times annually and realizes anequivalent or a higher yield of ratoon crop grain than main crop. The benefits of riceratooning under SALIBU technology extend to not only shortening the period for plant
growth and allowing farmers to harvest and sell more annually but also saving various
resources such as water, labour, seed and topsoil as well as their associated costs
owing to the omissible sowing and land preparation. The collaboration study started toproof that it needs lesser volume of irrigation water per one crop season. It means theincrease of water productivity. Introduction of this technology to rice farming small
holders must allow to solve the multi-faceted challenges such as increasing yields,saving both carbon emission and use of resources, directly increasing annual incomeof small holder farmers, ending hunger and ensuring their investment to farming. So,
researchers are recommended to conduct study on this ratooning technology fromvarious aspects.

1323rd International Congress on Irrigation and Drainage
8-14 October 2017, Mexico City, Mexico

Q. 60
R60.1.??

`REFERENCES
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