Harvesting and Threshing Losses of Paddy In Several Types of Agro- Ecosystems in Indonesia

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1 Harvesting and Threshing Losses of Paddy In Several Types of Agro- Ecosystems in Indonesia Resa Setia Adiandri, Nikmatul Hidayah, Sigit Nugraha Indonesian Center for Agricultural Postharvest Research and Development (ICAPRD) Indonesian Agricultural Agency for Research and Development (IAARD) Jl. Tentara Pelajar 12. Bogor Indonesia setia_resa17@yahoo.com (corresponding author) Keywords: Paddy. harvesting losses. threshing losses. agro-ecosystem Abstract This study was conducted to determine the level of harvesting and threshing losses of paddy in several types of agro-ecosystems in Indonesia. Harvesting losses is a combination of losses at harvest time. and losses during temporary accumulation. Performance of harvesting losses was conducted through measurement of harvesting losses using nine boards method. The main principle of harvesting losses measurement using nine boards method is to calculate the number of paddy grains that fall and accommodated on nine boards during cutting process of paddy. and the amount of paddy grains that fall during temporary accumulation before threshing process. Measurement of harvesting and threshing losses of paddy were conducted in several types of agro-ecosystems from six locations in Indonesia. namely the tidal land (South Sumatra). the rain-fed land (East Java). the technical irrigated land (South Sulawesi. Central Java and Yogyakarta). and non-technical irrigated land (West Java). The result showed that the highest harvesting losses was showed on non-technical irrigated land in West Java (3.19%). while the lowest harvesting losses was showed on the rainfed land in South Sulawesi (0.61%). On the other hand. the highest threshing losses showed on tidal land in South Sumatra (1.42%). while the lowest threshing losses of paddy indicated by the technical irrigated land in Central Java (0.42%). INTRODUCTION Paddy is the most important and extensively grown food crop in the World. It is the staple food of more than 60 percent of the world population. It is mainly produced and consumed in the Asian region including Indonesia. In Indonesia. paddy is grown in several types of agro-ecosystem. Agro-ecosystem is a group of the region which almost has the same physical state of the environment in which the variability of plants and animals can be expected not significantly different (Amien I. 1997). There are several types of agro-ecosystem such as the tidal land. the rain-fed land. the technical irrigated land. and non-technical irrigated land. The tidal land is located in a zone/area around the beach which is characterized by the direct influence of the ebb and flow runoff water from sea water or even just affect the water surface. Most types of soil in tidal land are peat soils and acid sulfate soil. Both types of land is marginal ecosystems. The rain-fed land is land which is that its water sources for rice planting depend only on the rainfall. Thus. in the rain-fed land with short rainfall. the rice planting can be done only once a year. then the land is left fallow. The technical irrigated land is land that has irrigation networks where channel provider is separated from exhaust thus water supply and distributtion can fully regulated and measured easily. Non technical irrigated land is land 571

2 which obtain water supply from natural irrigation systems that managed by the community or village around the irrigation area. Each agro-ecosystems has different characteristics in terms of soil fertility. water availability and management techniques which may affect the productivity and quality of paddy and level of paddy loss. Related to the level of paddy loss. there are several factors that can also affect the level of paddy loss such as method of postharvest handling. the culture of a particular region. varieties. threshing instrument. season. tools and methods of measurement used. The loss of paddy can occur in every stage of postharvest activities. The highest percentage loss occurs at the stage of harvesting and threshing paddy are estimated to be greater than 9% (BPS. 1996). Study conducted by the International Rice Research Institute (IRRI) reported that the expected rate of postharvest loss of 5-16% occurs during harvesting. threshing and cleaning. while 5-21% occur in the post-harvest process of drying. storage and milling (Ditjen P2HP. 2007). Ananto et al. (2003) reported that the level of rice yield losses during postharvest handling reaches 20-21%. on harvesting about 9% and on threshing about 5%. Harvesting systems were highly correlated with social factors and local culture which affects at a later stage threshing activities and yield loss factor. Harvesting paddy by individual system with number of harvesters can cause a lot of spilled grain. But the harvesting rice with a group or team system easily controlled. so as to reduce the level of paddy loss. Rice threshing is generally done in two ways that are manually or mechanically by pedal threser or power threser. Manual threser provide greater potential loss. It is due to inadvertent harvester in doing threshing and because of narrow pedestal so many grains are throw out of the pedestal. Nugraha et al. (2007). had been doing research to get rate of postharvest rice yield loss in three agro-ecosystems. The results showed that the cumulative yield loss of postharvest handling on irrigated land ecosystems was 13.35%. on rain-fed land was 10.39% and loss on tidal land ecosystems was 15.26%. The loss occurs at harvest stage. rice gathering. transporting rice. threshing delay. thresing. drying. storage and milling grain. Nugraha et al. (2007) reported that agro-ecosystems has influence on culture. behavior and way of harvesting rice. In irrigated ecosystems. tidal energy harvester is more aggressive in harvesting to get results as much as possible. while at the rainfed ecosystem energy harvesters more careful in cutting the rice. so that the shock can be reduced when cutting In recent years. several new varieties and rice postharvest technology innovation have been developed so that repeated measurements is necessary to determine the level of post-harvest rice yield loss. In addition. erratic climatic conditions also become one of the factors needed consideration of these measurement. These measurements is expected to provide latest data of postharvest rice loss to update the old measurement data which is allegedly irrelevant. Relevant data of loss measurement will provide decisive policy-making accuracy of national food stocks. national rice production. balance of trade and balance of exports and imports rice. The objective of this research was to determine the level of harvesting and threshing loss of paddy in several types of agro-ecosystems in Indonesia. Performance of harvesting losses was measured using nine boards method. and observations of threshing loss was calculated based on general guidance of postharvest losses measurement (Badan Litbang. 2011). This method was known as the best losses measurement method and proved closed to real measurement with directly collect paddy from the farmer land after harvesting process (Nugraha et al. 2011). 572

3 MATERIAL AND METHOD Study Area This study was conducted in 2012 in several types of agro-ecosystems from six locations in Indonesia. namely the tidal land (South Sumatra). the rain-fed land (East Java). the technical irrigated land (South Sulawesi. Central Java and Yogyakarta). and nontechnical irrigated land (West Java). Harvesting Losses Measurement General procedures in the measurement of harvesting losses using nine boards method are: 1) making of harvest tile plot sized 5m x 5m in paddy fields that ready for harvest; 2) put the observation boards on the harvest tile plot randomly; 3) the process of harvesting/cutting of paddy; 4) Stacking pieces of paddies on a pedestal of temporary stacking; 5) counting grains of paddy scattered on board observations; and 6) calculation of paddy left on a pedestal of temporary stacking (after pieces of paddies were threshed). Measurement of harvesting losses was begun in cutting process of paddy until temporary stacking. so that percentage of harvesting losses consist of value of losses in harvesting time and value of losses in temporary stacking that stated into weight percentage (equation 1). SP = SSP + SPS (1) Annotation : SP = Harvesting Losses SSP = Losses of Harvest time (cutting process of paddy) SPS = Losses of Temporary Stacking Measurement of losses in harvest time was done refers to general guidance of losses measurement method of paddy postharvest using nine boards method. Boards were used in this measurement had length 40 cm. widht 14 cm and thickness 3 cm. Its surface was coated with gunny to accomodate paddy scaterred during cutting process (Figure 1). The boards randomly put on the tile plot sized 5 m x 5 m which ready to be harvested (Figure 2). The amount of paddies on these nine observation boards were taken and calculated to be converted with conversion table of harvesting losses (Table 1). In special case if amount of paddies are not provided on the table. the losses value is determined with interpolation method using scale/number on the table. Formula of the losses of harvest time was shown on Equation 2. Measurement of temporary stacking was done by putting amount of pieces of paddies on pedestal directly at harvest time. After harvesting finished. calculating amount of good paddies scattered on pedestal were done. multiplied with weight of one harvest dry paddy (GKP). Weight of one harvest dry paddy was assumed equal with g. Formula of the losses of temporary stacking was shown on equation

4 SSP = (2) SPS = (3) Bg t = (4) Annotation : Bs k = weight of losses from conversion table of losses in harvest time Bg t = The number of paddy scattered during temporary stacking (kg) which converted into 1 ha Bt = The number of paddy scattered on pedestal of temporary stacking G = mean of weight were accounted from weight of 1000 of paddy at harvest s moisture content which converted into kilogram Note : if weight measurement of 1000 paddy wasnot done can be assumed that weight of one paddy = g A u = the tile plot area Bg p = The number of paddy resulted from harvesting (A u ) on tile plot (kg) converted into kg/ha = kg x /A u Threshing Losses Measurement Observations of threshing losses calculated based on general guidance of postharvest losses measurement (Badan Litbang. 2011). with losses criteria consist of the amount of paddy that was thrown out of a pedestal used by farmers which was small in size (T1). the paddy could not be threshed and still attached to the paddy straw (T2). and the paddy was carried along with impurities such as leaves. panicles and paddy straw (T3). The calculation of T1. T2 and T3 if not possible to be weighed. weighing calculation is done by counting the number of good grain then multiplied by the weight every single paddy (0.022 g). The layout of the losses measurement of paddy threshing displayed on Figure 3 and threshing losses calculation method was shown in Equation 5. Threshing Loss = (5) Annotation : A = Threshing machine (gebot) B = Farmer s pedestal threshing C = Pedestal threshing for losses obervation T 1 = The number of paddy scattered outside farmer s pedestal T 2 = The number of paddy still attached on paddy straw because it can not be threshed T 3 = The number of paddy was carried along with impurities of paddy B0 = The weight of paddy resulted from threshing process (kg) BT1 = The weight of paddy scattered outside farmer s pedestal (T1 x 0.022g) BT2 = The weight of paddy still attached on paddy straw because it can not be threshed (T2 x 0.022g) BT3 = The weight of paddy was carried along with impurities (T3 x 0.022g) 574

5 RESULT AND DISCUSSION Performance of Postharvest Handling in Some Provinces Activities of paddy postharvest handling are different for some area. This difference is directly or indirectly affect the loss rate of paddy. The perfomance of postharvest handling in some province are presented in Table 2. Table 2 showed several of postharvest activities in some province such as harvesting. temporary stacking. threshing. drying and milling. Harvesting system in some area such as South Sumatera. Yogyakarta. Central Java. and East Java were conducted by a group/team with a total membership of people using sickle by upper cutting. Meanwhile in South Sulawesi and and West Java. the harvesting system done by bottom cutting. Step of temporary stacking was not done by all region. for example in Yogyakarta and Central Java. In this area. the paddy which has been harvested packed directly into the sack without temporary stacking so that loss of temporary stacking while harvesting process can be avoided. For the threshing process. most of the region already used the machine thresher except in West Java which still use manual thresher. For the drying and milling stages there were no distinction between one area to another. The farmers still utilize the sun drying to dry their paddy where the milling process were two phase without separator. Measurement of Harvesting Losses There are many factors influence the harvesting losses : 1) aging of paddy. when it is harvested before the optimum aging will result in bad quality of grain. especially in content of immature and chalky grains are very high. whereas when harvest is done after the optimum aging causing high loss because the paddy in the panicle is begin brittle. so that it can thresh easily in the cutting process. 2) the system of harvesting that be referred by farmer. in the independent system there s no limitation in the number of people for harvesting so that causing in high loss. whereas on the group system. there is limitation in the number of people for harvesting between people. so that it can more pressing the loss value. 3) system. tools and harvesting method. which is using of tools and methods to cut paddy. There are three ways to cut paddy. that is upper cutting. center cutting and bottom cutting. Those factors will affect on the result of harvesting loss and temporary stacking. Two components as principle observation in the measurement of harvesting losses are 1) the number of paddy that down on the cutting process which can be accommodated on the nine boards. and 2) the number of paddy that down on the temporary stacking before threshing process. Measurement of harvest losses of paddy were conducted in several types of agro-ecosystems from six locations. namely the tidal land swamp (South Sumatra). the rain-fed land (East Java). the technical irrigated land (South Sulawesi. Central Java and Yogyakarta). and non-technical irrigated land (West Java). The observation result in the production rate. temporary stacking losses. and harvesting losses with nine boards method are presented in Table 3. Table 3 showed that grain production turned out to be highly variable between the measured region. South Sumatra and East Java. where the samples were taken at tidal land and rainfed land. rice production per hectare respectively 5200 kg per hectare and 5494 kg per hectare. While for the technical irrigated and nontechnical irrigated land from four other provinces. namely Yogyakarta. Central Java. West Java and South Sulawesi which are the granary rice. its rice production between kg/ha. 575

6 Paddy losses that occurs in harvesting is influenced by many varieties of rice planted. harvesting. crop moisture levels. systems. ways and tool of harvesting and soil conditions that are being harvested. On the tidal swamp land (South Sumatra). farmers do harvest by center cutting then threshing using a threshing machine (power thresher). Potential harvesting losses probably occurs during cutting because of sickle shock so that the grain detached and fell to the ground. The paddy losses also may occur when the temporary stacking where a lot of grain is separated from its panicle. Harvesting losses in this land was about 1.48%. This rate is higher than the national harvesting losses rate is about 1.20% (BPS. 2008). Potential harvesting losses on this land probably occurs during temporary stacking where a lot of grain is separated from its panicle. The result of harvesting losses from technical irrigated land in Central Java and South Sulawesi showed quite low value and were below the national harvesting losses rate between 0.61 to 0.72% in the same variety of paddy that is Ciherang. The low harvesting losses that occurred in the technical irrigated land from the both provinces were also heavily influenced by the condition of the plant at the time of measurement. where the rice plants harvested in good health and have reached the optimum harvest time shown by average harvested moisture content of 24.5% (Damardjati. 1981). The results of harvesting losses measurements performed on non-technical Irrigated land from Garut District. West Java indicated that harvesting losses was still quite high (3.19%). it was higher than the national harvesting losses rate 1.2% (BPS. 2008). The high of harvesting losses mainly due to the magnitude of the losses on temporary stacking. The amount of grain loss during temporary stacking reached grams. equivalent to kg/ha of dry grain harvest. This suggests that grain loss due to errors harvester behavior itself which was about 3% of the real production to be obtained by farmers. Efforts to reduce harvesting losses can be done by changing the manner and behavior of the usual harvest way by reducing temporary stacking of paddy after harvest. This can be done when harvesting is done by upper cutting and then put the pieces of paddy directly into sacks that have been provided as practiced by farmers in Yogyakarta and Central Java. The use of sacks can reduce both the harvesting losses. and transporting losses before threshing process. Measurement of Threshing Losses Development of new variety of paddy recently caused many problems in the postharvest technology especially in the harvesting loss. For the hard-threshing paddy varieties. the grain is very difficult to be threshed so that it becomes a limited factor for its development widely. Observations of threshing losses calculated based on general guidance of postharvest losses measurement (Badan Litbang. 2011). with losses criteria consist of the number of paddy that was thrown out of a pedestal used by farmers which was small in size (T1). the number of paddy could not be threshed and still attached to the paddy straw (T2). and the number of paddy was carried along with impurities such as leaves. panicles and paddy straw (T3). If the calculation of T1. T2 and T3. is not possible to be weighed. weighing calculation is done by counting the number of good grain then multiplied by the weight every single paddy (0.022 g). Good threshing process is when all the pithy grain detached from its panicle. The size bundle of paddy and slam frequency affect the release rate of grain from the panicle (Nugraha et al. 1999b; Setyono et al. 1993b). The ratio between rice and paddy. and the threshing losses from many types of Agro-ecosystem are presented in Table 4. The ratio between rice and paddy is determined by harvesting method/cutting method of paddy. When threshing process using manual method (called Gebot). or using threshing machine with hold-in model. cutting process will be done with bottom cutting method which 576

7 is 5-7 cm from end stem of paddy. On the other hand. when threshing process using through-in model. cutting process will be done with on top of cutting method which is 5-7 cm under the flag leave of paddy. The lower in cutting of paddy will affect on a higher ratio between rice and paddy. conversely the longer in cutting of paddy straw will result the lower value in the ratio of rice and paddy. In addition. ratio between rice and paddy also affected by the harvesting moisture content. content of good grain on the paddy panicle. and cleanness when doing threshing process. Table 4 shows that the ratio between rice and paddy in four provinces that represent several types of agro-ecosystems. namely South Sumatera (the tidal swamp land). East Java (the rain-fed land). Yogyakarta and Central Java (the technical irrigated land) higher than that produced by the other two provinces. namely South Sulawesi (the technical irrigated land) and West Java (the non-technical irrigated land). This happens because of differences in how to cut the paddy. Upper cutting way will result in a higher ratio than bottom cutting way. In South Sulawesi. harvesting done by bottom cutting since adapted to the threshing machine used while in West Java the threshing process still done manually. Performance of threshing losses in several types of agro-ecosystem from some location were still quite high such as in the non-technical irrigated land (West Java) about 1.28% and in the tidal swamp land (South Sumatera) reached 1.42%. Generally. the result can be concluded that the highest threshing losses showed on tidal land in South Sumatra (1.42%). while the lowest threshing losses of paddy indicated by the technical irrigated land in Central Java (0.42%). Nugraha et al. (2007) reported that threshing losses in the irrigated land was about 1.98%. in the rain-fed land was about 1.05% and in the tidal land was about 1.62%. Potential loss occurred in the number of grain thrown out from the pedestal while the threshing process. This is because of the pedestal that used for threshing process was relatively narrow which average size of 3 x 4 m or 4x4 m. while the size pedestal as SNI recommended is 8 mx 8 m. CONCLUSION Activities of paddy postharvest handling are different for some areas depends on the type of agro-ecosystems. Agro-ecosystems has effect on culture. behavior and way of harvesting paddy that can affect the value of post-harvest loss. including loss of harvesting and threshing. The research result showed that the highest harvesting losses was showed on the non-technical irrigated land in West Java (3.19%). while the lowest harvesting losses was showed on the rainfed land in South Sulawesi (0.61%). On the other hand. the highest threshing losses showed on tidal land in South Sumatra (1.42%). while the lowest threshing losses of paddy indicated at the technical irrigated land in Central Java (0.42%). Literature Cites Amien I Karakterisasi dan Analisis Agroekologi. Pusat Penelitian Tanah dan Agroklimat. Bogor. Ananto E. A. Setyono dan Sutrisno Panduan teknis penanganan panen dan pascapanen padi dalam sistem usahatani tanaman-ternak. Puslitbangtan. Bogor. Badan Litbang Pertanian Pedoman Umum Pengukuran Susut Pascapanen Padi Metode Sembilan Papan. Badan Penelitian dan pengembangan pertanian. Kementrian Pertanian. Biro Pusat Statistik Survei susut pascapanen MT1994/95 dan MT Kerjasama BPS. Ditjen Tanaman Pangan. Badan Pengendali Bimas. Bulog. Bappenas. IPB. dan Badan Litbang Pertanian. 577

8 Damardjati Damardjati DS. Suseno H. Wijandi S. Penentuan umur panen optimum padi sawah (Oryza sativa L.). Penelitian Pertanian. 1981; 1:19:26. Direktorat Jenderal P2HP Deptan Pedoman Teknis Penanganan Pascapanen dan Pemasaran Gabah. Direktorat Jenderal Penanganan Pemasaran Hasil Pertanian. Departemen Pertanian. Nugraha. S. A. Setyono dan Sutrisno Perbaikan penanganan pascapanen padi melalui penerapan teknologi perontokan. Simposium Penelitian tanaman pangan IV. Bogor November Nugraha. S. Thahir. R. dan Sudaryono Keragaan Kehilangan Hasil Pascapanen Padi Pada 3 (Tiga) Agroekosistem. Buletin Teknologi Pascapanen Pertanian Vol. 3. Hal : Nugraha. S Laporan Akhir Kegiatan (Pelaksanaan kegiatan penelitian). Penanganan Susut Pascapanen Padi Dalam Mendukung Peningkatan Produksi Beras Nasional (P2BN). Balai Besar Penelitian dan pengembangan Pascapanen Pertanian. Badan Penelitian dan pengembangan Pertanian. Kementrian Pertanian. Setyono. A. Sutrisno dan S. Nugraha Pengujian pemanenan padi system kelompok dengan memanfaatkan kelompok jasa pemanen dan jasa perontok. Penelitian Pertanian tanaman pangan. 578

9 Tables Table 1. Conversion table of losses measurement in harvest time using nine boards method. The number of paddy (grains) Losses The number of paddy (grains) Losses The number of paddy (grains) Losses The number of paddy (grains) Losses The number of paddy (grains) Losses (1) (2) (1) (2) (1) (2) (1) (2) (1) (2) Table 2. Performance of Postharvest Handling in Some Provinces. Postharvest activity South Sumatera Yogyakarta South Sulawesi Province of Center Java West Java East Java Harvesting Sickle. Upper cutting Sickle. Upper cutting Sickle. bottom cutting Sickle. Upper cutting Sickle. bottom cutting Sickle. Upper cutting Temporary Be present Packed directly Be present Packed directly Be present Be present Stacking into the sack into the sack Threshing Power thresher trough-in Power thresher through-in Pedal thresher hold-in Power thresher Through-in Manual method (called Gebot) Power thresher trough-in Drying Sun drying Sun drying Sun drying Sun drying Sun drying Sun drying Milling Two phase. without separator Two phase. without separator Two phase. without separator Two phase. without separator Two phase. without separator Two phase. without separator 579

10 Table 3. The observation result in the production rate. temporary stacking losses. and harvesting losses with nine boards method. Type Of Agroecosystem Production rate The weight of paddy from tile plot harvest (kg) The number of paddy on the board (grain) The weight of paddy in the temporary stacking process Harvesting Losses (%) The technical irrigated land (Yogyakarta) The non-technical irrigated land (West Java) The technical irrigated land (Central Java) The rain-fed land (East Java) The tidal swamp land (South Sumatera) The technical irrigated land (South Sulawesi) (118.54) (17.58) (62.64) (64.96) (54.72) (32.84) Note: (-) the temporary stacking process was not done in the harvesting process. the paddy directly packed into the sack after cutting process Table 4. The ratio between rice and paddy. and the threshing loss from many types of Agro-ecosystem. Type Of Agroecosystem The ratio between rice and paddy The number of paddy that was thrown out of a pedestal The number of paddy still attached to the paddy straw (kg/ha The number of paddy was carried along with impurities (kg/ha The threshing loss (%) The technical irrigated land (Yogyakarta) The non-technical irrigated land (West Java) The technical irrigated land (Central Java) The rain-fed land (East Java) The tidal swamp land (South Sumatera) The technical irrigated land (South Sulawesi)

11 Figures Figure 1. Observation board for measurement of harvesting losses Figure 2. Laying down method of observation s board on harvest tile plot for measurement of losses in harvest time (note: formation of boards can be altered; number one until nine were observations boards) 581

12 582 Figure 3. The layout of the losses measurement of paddy threshing.