Trop. Agr. Develop. 6（3 1）：38 － 46，2019

Information

A Special Transplanting Method, Cut-Stem Transplant (A Sit Phyat), Practiced in Deep-Water Areas of Bago Region in

Yu MON 1, Yoshinori YAMAMOTO 2, *, and Mie Mie AUNG 1

1 Yezin Agricultural University, Yezin, Naypyitaw District, Myanmar 2 Faculty of Agriculture, Kochi University, Nankoku, Kochi 783-8502, Japan

Abstract Of the 7,000,000ha of cultivated rice in Myanmar, submerged and deep- water areas account for 13.5% of the total area. Therefore, for cultivating submersion resistant varieties, the use of deep water- adapted cultural practices and/or the construction of drainage and flood protection infrastructures need to be undertaken to provide greater resilience from flooding especially in the delta region (Ayeyarwaddy, Bago and Yangon). The use of the cut-stem transplant method of rice production is practiced in Zee Pin and Ywa Houng villages (deep-water areas) situated in the Thanatpin Township, Bago Region. The method originated in Zee Pin village and was discovered accidentally when farmers observed root outgrowth from stem cuttings. At present, it is also practiced in Ywa Houng village in the Thanatpin Township. The seeds of the deep-water rice variety, Pawsan, are directly seeded in May after the start of the monsoon, and the elongated stems are cut at about 30cm above the soil surface in September when the seasonal water starts to recede. The stem-cut seedlings are about 100cm long and then, are brought by boat to the field where they are to be transplanted. Transplanting is done by women using wooden forks (Kauk Side Doke), placed between the first and second elongated internodes, to place the cuttings. Harvesting occurs around mid-December. Although the farmers believe that the yield from such a method is superior to the direct seeding method, further investigations are required to gain a clearer understanding of the benefits of the former method. Key words: Bago region, Cut-stem transplant, Deep-water area, Myanmar, Pawsan, Rice cultivation

ecosystem in Myanmar (Table1). Introduction In contrast to this five-zone classification, Matsuda Rice is grown on over 7,000,000 ha in Myanmar, (2009) classified the rice-growing areas in Myanmar into which represents more than half of the available arable four agro-ecological zones. These are the ‘Delta Zone’, land. The rice ecosystems here include lowland (rain- such as occurring in the Ayeyarwady, Yangon and Bago fed and irrigated), submerged, deep-water, upland or regions, the ‘Coastal Zone’, the ‘Central Dry Zone’ and Taungya (upland field with slopes), and sea water intru- finally, the ‘Mountainous Zone’. This categorization is sion areas (Rice Division, 2016). Kyaw et al (1977) sub- based on soil topography, annual rainfall, agricultural sequently classified the deep-water areas in Myanmar land use and administrative boundaries. The author into shallow-water, medium deep-water and deep-water described how high-yielding varieties (HYVs) replaced areas as follows. The shallow water area is one with less local varieties after the introduction of the Green than 50cm in depth, while medium depth is 50-200cm Revolution technology in the mid-1970s’ to early 1980s’. and the deep-water area is over 200cm in depth. In terms Although HYVs replaced almost half of the paddy fields of the production areas of the rice ecosystems of Myan- in the delta region, the remaining zones were still be- mar, lowland accounts for 68% of the monsoon-cultivated ing cultivated, using local varieties. The replacement areas while submerged and deep-water areas occupy by HYVs is not possible throughout the complete delta 13.5%, with -prone areas making up a further region because some places are affected by floods, and 12.9% and the remainder (5.6%) being occupied by an up- so intermediate-type varieties are impossible to grow. land ecosystem, Taungya and salt water intrusion areas Owing to rainfall and resultant flooding patterns, (Rice Division, 2016). The importance of the submerged drainage and flood protection infrastructures had to be and deep-water areas is obvious when it is considered installed in the delta region (GRiSP, 2013). The Myanmar that the two make up the second largest rice-growing government is using the following methods to protect crops from flood damage; construction, rehabilitation,

Communicated by K. Irie the operation and maintenance of embankments, dikes, Received Apr. 20, 2018 polders, drainage channels and sluice gates along the Accepted Jul. 11, 2018 main river system in the delta region (MOALI, 2016). * Corresponding author [email protected] However, there are still deep-water areas here not ame- Mon et al.: A special rice transplant method 39

Table 1. The cultivated area in 7 ecosystems in relation to and adapted method in accordance with flood conditions water conditions in Myanmar in 2015-16. in the Bago region. The cut-stem transplant method of Ecosystem type Rice cultivated area (ha) deep-water rice is practiced here. Usually, transplanting Lowland 4,279,087 is done with intact seedlings (seedlings with attached Submerged 533,857 roots) which are considered to be very important to Deep-water 306,134 absorb water and the necessary nutrients from the soil Drought prone 802,248 before seedling establishment (Yamamoto et al., 1978). Taungya 189,774 However, this transplant method is applied to seedlings Upland 97,495 without root growth. The purpose of this survey was to Sea water intrusion 10,046 Total area 6,218,641 examine the efficacy of the cut-stem transplant method [Source] Rice Division 2016 (A Sit Phyat) of rice growing practiced in the deep-water area of Thanatpin Township, Bago Region in Myanmar. nable to such methods. Thus, although the rice varieties Methods mostly grown in the monsoon season are HYVs such as Manawthukha, Sinthukha, Ayeyarmin, Shwewahhtun, Research sites Sinthwelatt and Kyawzeya, local varieties belonging to The research was conducted in the villages of Ngasein, Meedon and Hnankar are still being grown Zee Pin and Ywa Houng in the Thanatpin Township (Rice Division, 2016). (TS) located in the Bago Region. These two villages There are several conventional rice crop establish- are situated about 10km south and 21km south east of ment methods practiced throughout the world, the most Thanatpin, respectively (Fig. 1). commonly of which are direct seeded and transplanted rice. However, there are some locally-used crop estab- Interview methods and the collection of meteoro- lishment methods that are dependent on the peculiarities logical data of the local land situation and weather conditions. Dry Three farmers who had extensive experience in the seeding is fairly common, but transplanting or double cut-stem transplant method were questioned to explore transplanting is sometimes practiced in deep-water the history of this method in Zee Pin village in May 2017. areas (De Datta, 1981). Double and triple transplanting In Ywa Houng village, interviews with farmers were con- are practiced in the flooded areas of Indonesia (Noorsy- ducted in three phases to develop a clear understand- amsi et al., 1984), (Puckridge, 1988) and ing of this particular method, in the period August to (Singh et al., 2004). Likewise, there is a locally applied December 2016. In total, nine farmers were interviewed

Fig. 1. Map of the study site. 40 Trop. Agr. Develop. 63（1）2019 about their reasons for using this method, what was Characteristics of water condition for rice cultivation in involved in land preparation, the raising of seedlings, the the research sites effects of changing water depths in the fields, cultivation The average rainfall distribution of Thanatpin for methods and resultant yields in comparison to other rice the ten-year period from 2007-2016 is shown in Fig. establishment methods. 2. Total annual rainfall here was around 3,300mm per To describe the rice-growing environment in the annum. Generally, rainfall starts in May with the onset research sites the following parameters were used. The of the monsoon. The intense rainfall months are June, rainfall (mm) and rainy days in a 10-years average, last July and August and generally, flooding occurs at that year’s (2015) and the current year’s (2016) rain falls that time. Of these months, July has the most intense rainfall occurred in the Thanatpin Township area, with data from and rainy days. After August, the rainfall decreases the Thanatpin Township Agriculture Office were used. and generally, finishes by November. According to the Moreover, information on the area of rice cultivated in results obtained in interviews, the field water in Ywa each ecosystem in the Thanatpin area was sourced from Houng is around 11cm at the beginning of June and the said office data. around 120cm from July to August. The water starts to recede in September when it is around 60-70cm in depth. Results However, the deepest water in Zee Pin village is about Rice cultivation in relation to water depth in the 150cm. Thus, deep-water areas in Thanatpin can be clas- research sites sified as medium-deep areas under the Kyaw et al (1977) Bago is situated at latitude 17o20’N and longitude classification as previously mentioned. 96o28’52”E and is 18m above sea level, 68km from Yangon (Fig 1). Thanatpin is situated at 17o12’42”N and The history of the cut-stem transplant method in Zee Pin 96o18’11”E and is 9m above sea level situated beside village the Bago-Sittaung canal (Fig 1). These two are lowland The cut-stem transplant method started in the areas and are included in the Sittaung delta region. 1960s’ at Zee Pin village and was first used by U (Mr.) Here, flooding occurs frequently during the monsoon Ba Chaw of the Mon tribe. In 1962, an 8-km length of season. Owing to overflow water from the Bago-Sittaung embankment was constructed from Pyon Pauk vil- canal, most of the rice fields in Thanatpin are flooded lage, through A Paing village and on to Nivan village as well. As a percentage of the area of rice cultivated (Fig. 3), to protect the area from overflow water from here (60,000ha), submerged and deep-water areas oc- the Bago-Sittaung canal. However, the water became cupy 44% of the cultivated area (Thanatpin Township trapped inside the embankment due to poor drainage Agricultural Office, 2016). The areas of rice cultivation management, resulting in some lower fields being sub- in Zee Pin and Ywa Houng villages are also flooded with ject to deep-water flooding. Zee Pin village was located deep-water. Therefore, deep-water rice varieties such as in this lower area and the seasonal field water depths Yoesein, Yoedayar and Pawsan are grown in Ywa Houng at present. 900 800 Average annual Rice cultivation in Bago region 700 rainfall ) 3,300mm The area under rice cultivation in the Bago region m 600 was 1,119,272ha in 2015-16. This included moderate wa- 500 ter areas (72.46%), submerged areas (7.7%), deep-water 400 areas (11.72%), drought-prone areas (7.83%) and upland Rainfall ( m 300 areas (0.28%) (Rice Division, 2016). The deep-water area 200 occupied 11.7% of total cultivated area. Therefore, it was 100 0 t necessary to consider three main factors to assure effi- r s e July May Jun e tober April cient rice production in this region, namely the effective- nuary Marc h Aug u cember J a O c p tem b e r ness of varieties adapted to deep-water conditions, the February D e Novem b Months S e use of specific cultural practices that provide resilience to flooded conditions and the implementation of drain- Fig. 2. Average rainfall distribution for the Thanatpin Township in Bago Region, Myanmar for ten years age or flood protection measures. (2007-2016). [Source] Thanatpin Township Office. Mon et al.: A special rice transplant method 41

Fig. 3. Embankment through Zee Pin to Nivan village in Bago Region, Myanmar.

increased. The cultivated varieties at that time were Ta Yar 2 mutant could now be cultivated and it was possible Taung Po (floating rice) in the deepest-water areas and to apply urea fertilizers. Hence, the yield of summer rice Pawsan and Shwe War Gyi in the medium deep-water was 5-5.8 t/ha while Myanmar’s average paddy yield in areas. As a result of this new flooding regime, the nurs- 1995 was only 3.08 t/ha (DAP, 2012). Therefore, the ery fields of Pawsan and Shwe War Gyi were damaged. farmers gained more profit from summer rice. However, Most of the seedlings from these areas died and a small as there was an overlap of the monsoon rice season and number of seedlings from shallow places were lodged. the summer rice cultivation one through November A farmer, disappointed by the damage to his nursery and December, farmers abandoned growing the former field, cut the elongated stems and threw these on the which was harvested from late November to December, fields. Afterwards, it was observed that the stem cuttings the time when field preparation for summer rice had to established root systems and from this, the method was start. initiated. Not only was there transplanting, but also the stem cuttings were spread on the muddy soil without Adoption and implementation in Ywa Houng village transplanting. In such cases, some farmers realized The cut-stem transplant method has disseminated that due to birds perching on the stem cuttings, those from Zee Pin village to Ywa Houng village, at least since dipped into the mud and which enhanced rooting. The 2012. This method was started in damaged fields sub- maximum area where the cut-stem transplant method ject to direct seeding in 2012. At that time, about 2% of was practiced was 10ha. Sometimes, this method was the total cultivated area was tested with the cut-stem used to substitute for the damaged direct-seeded fields. transplant method with the rest remaining under the Transplanting was done in October after the water re- direct-seeding method. The yield of the cut-stem trans- ceded by using wooden forks (Figs. 4F, G, H). The yield planted fields was higher than that of the direct-seeded of the cut-stem transplant method averaged between 1.3 fields and the cultivated area using this method was to 1.5 t/ha. then increased to 5% in 2013. In 2014, again another 5% The flood depths increased throughout the late of the fields were cultivated with the cut-stem transplant 1960s’, forcing the farmers to sow summer rice in 1982 method while 1% used normal transplanting because and whose area expanded gradually. In 1995, a summer- the seedlings, established in the shallow-water area, did rice project was commenced by the government, which not lodge and did not produce additional node due to was able to supply sufficient water for summer rice comparatively less flooding during the nursery period in cultivation. HYVs such as Manawthukha, Sinthukha and that year. Therefore, the stems of the seedlings could 42 Trop. Agr. Develop. 63（1）2019

(A) (F)

(B) (G)

(C) (H)

(D) (I)

(E) ( J )

Fig. 4. Transplanting and growth of the Pawsan rice variety following the cut-stem transplant method. (A) seedling establishment at one month after seeding, (B) growth of seedlings in increasing water depths, (C) lodged seedlings in the nursery field before transplanting, (D) the cutting of the seedllings and removal of the dead leaves, (E) stem-cut seedlings brought by boat to the transplanting field, (F) the wooden fork used for transplanting, (G) holdings of the seedlings between the blades, (H) placing the blade between the first and second elongated internodes, (I) the cut-stem rice seedlings growing under receding water and (J) stem-cut transplanted fields at the harvesting stage. Mon et al.: A special rice transplant method 43 not be cut and hence, they were transplanted, using the seedlings are cut about 30cm above the soil surface and normal method. However, the monsoon finished early transplanted (Fig. 4D). Depending on the depth of the in 2014 and the yield of the cut-stem transplanted fields flooding, time for transplanting will vary from the end of decreased due to insufficient moisture during the grain- August to September. The water depth at transplanting filling period. Therefore, the area of these fields was is usually about 60cm (Fig. 4G). According to the Myan- reduced to 3% in 2015 while 1% was again planted with mar ethnic culture, the men usually cut the stem and the the normal-transplanting method, with the remainder women transplant them. In this way, men and women being direct-seeded fields. In contrast, the rainfall was share the work load of the transplanting process. The sufficient for the cut-stem transplant method in 2015, elongated stems are cut and the dead leaves removed and the cultivated area was increased again, that year (Fig. 4D). Then, the cuttings are brought to the field by to 7%. In 2016, normal transplanting in the shallow-water boat and placed near the women doing the transplanting area was about 3% with the rest being direct-seeded (Fig. 4E), who use wooden or iron forks to transplant fields. Moreover, the area using the cut-stem transplant them because the water is too deep to do this by hand. method decreased to 2% in 2017 because the drainage Farmers say that transplanting with iron forks spread system had improved and there was less damage from from Thaton, Kyeik Hto and Bilin TS situated in the flooding. Not only was the cut-stem transplanted area Mon State. Transplanting labourers travelled to Kyeik reduced that year, but the normal-transplanting area was Hto, which borders Thanatpin and learned and applied also reduced to 2% as well. Transplanting costs had be- methods used in Thanatpin. Transplanting with forks come higher so, limiting the ability of poorer farmers to was also practiced in Malaysia (Nozaki et al., 1978). The apply either of the transplanting methods. In addition to transplanting forks is locally made and consists of iron this, the sale price of alternated crops such as legumes or wooden blades attached to a wooden stick. Each blade increased. As the farmers wished to cultivate these, the is 22cm long and the wooden stick is 75cm long (Fig. direct-seeded area was increased. 4F). Women hold the cuttings with the left hand and Although the direct-seeding method area could transplant with their right one by placing the mid por- be harvested earlier than the rice from the cut-stem tion of the lowest (first) and second nodes between the transplant method and would thus favor alternate crop blades (Figs. 4G, H) and insert the cuttings to a depth of cultivation, the yield of direct-seeded fields was less than 4 to 8cm with a space of about 23cm × 23cm. Normally, the latter due to weed infestation and its vulnerability the time required to transplant one seedling by women to lodging. Also, although the harvesting time and the is about 3 seconds, and hence, 178 working hours are yield of normal transplanting are comparable to those necessary to complete a ha. Although the seedlings of the cut-stem transplant method, the profit is less due grow under deep-water conditions with the upper leaf on to slightly higher transplanting costs for the normal the water surface just after transplanting, the plants are method. In addition, the viability of normal transplanted erect one week after that, and the field starts to green crops would not be assured if flooding damage occurred (Fig. 4I). The farmers prefer a prolonged nursery period after transplanting because the transplanting time in this because as the seedling ages, it can become more resis- method is earlier than that for the cut-stem transplant tant to flood damage and a greater number of nodes and method. For these reasons, the farmers who cultivate internodes are produced. As a result, the seedlings can in deeper-water areas are still applying the cut-stem bear more tillers due to an increased number of nodes. transplant method at present. At harvest, the plants are more resistant to lodging (Fig. 4J) than direct seeded ones as the stem-cuttings The cultural practices attached to the cut-stem transplant have been inserted into the soil at depths of 4 to 8cm, method which favor deeper rooting in it. For this method, the field is roughly plowed in May Discussion after the start of the monsoon. Dry seeds of Pawsan are seeded in a dry field at a rate of 162 kg/ha in a nursery Characteristics of the cut-stem transplant method field. One month after seeding (Fig. 4A) before flooding Generally, in rice transplanting, seedlings that have occurs, urea fertilizers are applied at a rate of 25 kg/ha. been raised for 15-40 days in nursery are used (Rice Pawsan responds to flooding by the elongation of its stem Knowledge Bank, 2017). The seedlings raised here for a (Fig. 4B). However, the elongated plants tend to lodge long period, i.e. thirty days or more, usually, show more after the flood water recedes (Fig. 4C). Therefore, the severe transplanting damage due to root breakage with 44 Trop. Agr. Develop. 63（1）2019 the uprooting of more mature ones. The quality of the reported on transplanting seedlings by catching them root system of the seedlings at the transplanting time between the toes and thus placing them in deep-water plays an important role in reducing the transplanting areas, in the so-called “Waju” of Gifu Prefecture, used in damage, promoting seedling establishment and early previous times in Japan, again because the water depth growth in older seedlings (Datta, 1981). The cut-stem exceeded effective arm-length planting. transplant method, described in this paper, is very dif- As for the characteristics of the varieties adapted ferent from normal transplanting in that it uses very old well to this transplant method, tillering and rooting seedlings raised for 3-4 months, with these transplanted abilities from the elongated internodes and late matur- without a root system. They elongate the internodes dis- ing traits which never differentiate young panicles dur- tance in response to the rising water during the nursery ing the long nursery period (3-4 months) (Salam et al., period, attaining a length of about 1.5m. As previously 2004) are required to secure the yield. In regard to tiller- described, the stem is cut at about 30cm above the soil ing from elongated internodes, floating rice has a trait surface for transplanting. Transplanting of long and to produce tillers from the elongated nodes, especially aged seedlings raised for a long period in nurseries when the water is receding (Vergara et al., 1976; Suge, has also been reported in Indonesia (Noorsyamsi et al., 1994), although these tillers never emerge from these 1984), Vietnam (Puckridge, 1988) and India (Singh et nodes in normal rice varieties (Ogo, 1980; Hoshikawa, al., 2004) as double or triple transplanting in flooded 1989). The tillering ability of the elongated nodes of areas. However, seedlings used for such transplanting normal rice varieties needs to be determined. The are uprooted, that is, having roots. Therefore, the cut- preferred varieties such as Pawsan, Yoedayar, Yoesein stem transplant method is different from these methods and so on in Thanapin TS for this transplant method are although the seedlings age and length are almost the photoperiod sensitive local varieties of deep-water rice same. that flower at the end of October until the second week In this method, adventitious roots from the of November. elongated nodes, inserted in the soil play a role in establishing the seedlings and support their growth The advantages and disadvantages of the cut-stem afterwards. Generally rooting occurs from un-elongated transplant method nodes positioned on the lower parts in the soil and the Farmers believe that the yield of Pawsan follow- roots do not emerge from elongated nodes, although ing the cut-stem transplant method is higher than that these have rooting zones as well (Hoshikawa, 1989). for direct seeding plants (3-4 t/ha vs 1.3 to 1.6 t/ha) However, rooting from these nodes has been reported because this method prevents weed competition. Also, if the rice is grown under submerged conditions (Nitta this method is resistant to lodging because the plants et al., 1998). In the case of floating rice, rooting from the are placed at a depth of 4 to 8cm in the soil. Therefore, elongated nodes is commonly observed (Vergara et al., the root will attach firmly there and make the plants re- 1976; Inoue and Mochizuki, 1980; Nitta et al., 1999) as sistant to lodging (Fig. 4J). In addition, the nursery stock is rooting from internodes (Nitta et al., 1999). It was the for the cut-stem transplant material is seeded at the observation of the rooting from the elongated nodes by beginning of the monsoon season and the cuttings are farmers that resulted in the development of this specific transplanted after the water has commenced receding. transplant method in Zee Pin village, Thanatpin TS, Bago The seedlings are about 3 to 4 months old and very tall Region in Myanmar. when flooding occurs. Hence, the cuttings can survive It seems that a water depth of about 60cm (without the early seasonal flooding and any delayed flooding a flow) at transplanting with water gradually receding, (Salam et al., 2004), which can occur after the transplant- is necessary to ensure that the long seedlings, without ing of normal seedlings. Moreover, it appears to have roots, do not suffer dried-up leaves and stems, and that greater resistance to some pest infestations due to this conditions exist to promote growth. If there is a fast prolonged seedling period. Additionally, the harvesting flow of water, the transplanted seedlings, without roots, of the cut-stem transplanted plants is one week later than may easily float away. Moreover, with a depth of water the direct-seeded ones, which can be significant in the greater than about 60cm, it is impossible for farmers to avoidance of late season rain that sometimes coincides transplant the seedlings by hand. To overcome this, they with the harvesting of the latter plant. developed a specific tool for transplanting called the Thus, farmers use this method in fields with the “transplanting fork” (Figs. 4F, G, H). Suge (1987) has greatest water depth or as a substitute for the direct- Mon et al.: A special rice transplant method 45 seeded fields subject to damage by flooding, pests and/ prevailing conditions of deep water at transplanting time or weed infestations. Not only is greater damage likely in this area, and the labour involved in uprooting large during the growing season avoided, but this method is seedlings. also used in the seasons when the nursery field is dam- The cutting has to produce roots and tillers from aged by flooding and the seedlings are lodged. the elongated nodes under deep-water conditions after In addition, the labour force, required for the cut- transplanting to secure seedling establishment, subse- stem transplant method, is less than that for normal quent growth and a final yield. The varieties adapted transplanting because it is not necessary to uproot the to these areas that use this transplanting method, are seedlings from the soil. Only the elongated stems are varieties such as Pawsan, Yoedayar, Yoesein and so on cut above the soil surface. Besides that, the labourers’ which have all these traits as well as late-maturing one. transplanting is not required to bend as they use these In regard to the environmental conditions that wooden forks to transplant. pertain after transplanting of these specific seedlings, it Although this method can increase the yield, the is important that they are maintained immediately after cultivation cost is higher than that for the direct-seeding transplanting under deep water of about 60 cm without a method, and so preventing the use of this method by strong current, to avoid the drying up of the leaves and poor farmers. In addition, the transplanted plots are not stems before seedling establishment or the drift of the productive for the 4 to 4.5 months before transplanting. cuttings. Afterwards, the water should recede gradually Moreover, this method does not favor following crops so that there is enough water in the soil after flowering such as legumes or summer-rice cultivation, as the to promote subsequent growth and yield. harvesting time is one week later than that for the direct- The cut-stem transplant method has advantages seeding method. The yield will be reduced as well if the such as less transplanting time and reduced costs, com- monsoon finishes early and there is not sufficient mois- pared with the normal transplanting methods and allows ture for grain-filling to occur, resulting in a subsequent the production of a higher stable yield compared with reduction in the yield. Therefore, this method would not the direct-seeding method. However, it also has disad- be viable in areas where moisture retention is poor after vantages such as a greater working load and a later har- the monsoon retreats. vesting time compared with the direct-seeding method and these disadvantages make it difficult for farmers to Application of the cut-stem transplant method in plant other crops after the harvesting of rice. Myanmar’s current rice production This research demonstrates the possibility that this The cut-stem transplant method is applied in me- specific method may become redundant through the dium deep-water areas in Thanatpin TS. As described development of infrastructures in the irrigation system earlier, if the rice field is damaged and the rice plants but also due to the labor shortage and the opportunity are lodged, this method is a suitable way to exploit and costs involved in forgoing the income from succeeding salvage production from these fields. Nevertheless, if crops, even though it is a method very well adapted to flooding can be prevented through infrastructure such deep-water areas in Myanmar. as the construction of embankments or drainage chan- Acknowledgements nels, this method would not be required. However, time and precious investment are required for this to provide The authors wish to thank the Japan International protection from flooding in Myanmar. Therefore, this Cooperation Agency (JICA) for providing supporting method is essential to ensure maximum rice production funds for the interviews, central to this paper. in medium deep-water areas, for the foreseeable future. References Conclusion De Datta, S. K. 1981. Principles and Practices of Rice Production. The cut-stem transplant method used in the Bago John Wiley & Sons, Inc (New York) p. 246. Department of Agricultural Planning (DAP) 2012. Myanmar Region in Myanmar provides a very specific method, in Agriculture at a Glance, Ministry of Agriculture, Livestock that long seedlings with elongated internodes, which and Irrigation (Nay Pyi Taw) p. 34. have been raised for 3-4 months, are transplanted after Global Rice Science Partnership (GRiSP) 2013. Rice Almanac, 4th edition. International Rice Research Institute (Los Baños) pp. their stems have been cut at about 30cm from the soil 141-144. surface. The background to the development of this Hoshikawa, K. 1989. The Growing Rice Plant. Nosan Gyoson specific transplanting method is closely related to the Bunka Kyoukai (Tokyo) pp. 149-205. 46 Trop. Agr. Develop. 63（1）2019

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