Wetland Rice Cultivation Research Articles

Improving Nitrogen Fertilizer Management for Yield and N Use Efficiency in Wetland Rice Cultivation in Bangladesh

Improving Nitrogen Fertilizer Management for Yield and N Use Efficiency in Wetland Rice Cultivation in Bangladesh

Energy Utilization and Greenhouse Gas (GHG) Emissions of Tillage Operation in Wetland Rice Cultivation

In Malaysia, wetland rice is cultivated over two cropping seasons: the main season, from June to November, and the off-season, from January to June. The aim of this study was to investigate tillage operations in rice production in relation to actual field operations and under real field conditions for two rice cultivation seasons. The results showed that 80.7%, 17%, and 2.3% of the total time was spent on the actual operation, turning time, and reversing time, respectively. The results also showed that the mean effective field capacity, field efficiency, and fuel consumption were 1.2 ha/h, 80%, and 7.6 L/ha, respectively. The distribution of energy used in the first, second, and third tillage passes amounted to 37%, 33%, and 30% of the total energy, respectively. Fuel, machinery, and total GHG emissions were 62.4, 7.6, and 70 kg CO2eq/ha, respectively. Fuel represented the highest contributor of energy expenditure and GHG emissions. The distributions of GHG emissions in the first, second, and third tillage passes were 37%, 32%, and 31% of the total GHG emissions. The results reveal that carrying out minimum-tillage operations led to a reduction in environmental impacts.

Detection of Sedge Weeds Infestation in Wetland Rice Cultivation Using Hyperspectral Images and Artificial Intelligence: A Review

Sedge is one type of weed that can infest the rice field, as well as broadleaf and grasses. If sedges are not appropriately controlled, severe yield loss will occur due to increased competition with cultivated rice for light, space, nutrients, and water. Both sedges and grasses are monocots and have similar narrowed leaf characteristics, but most sedge stems have triangular prismatic shapes in cross sections, which differ them from grasses. Event sedges and grasses differ in morphology, but differentiating them in rice fields is challenging due to the large rice field area and high green color similarity. In addition, climate change makes it more challenging as the distribution of sedge weed infestation is influenced by surrounding abiotic factors, which lead to changes in weed control management. With advanced drone technology, agriculture officers or scientists can save time and labor in distributing weed surveys in rice fields. Using hyperspectral sensors on drones can increase classification accuracy and differentiation between weed species. The spectral signature of sedge weed species captured by the hyperspectral drone can generate weed maps in rice fields to give the sedge percentage distribution and location of sedge patch growth. Researchers can propose proper countermeasures to control the sedge weed problem with this information. This review summarizes the advances in our understanding of the hyperspectral reflectance of weedy sedges in rice fields. It also discusses how they interact with climate change and phenological stages to predict sedge invasions.

Forest conversion to agricultural lands: impact on soil physical characteristics

Forest conversion to other land uses, particularly for agriculture, has been prevalent worldwide, with Indonesia being particularly affected. The removal of forest cover, which exposes the organic matter to more severe climatic conditions, leads to a deterioration in the physical characteristics of the soil. This paper investigates the alterations in various soil physical properties when forests are converted into agricultural land uses, including fallow areas with shrubs, wetland rice cultivation, cacao plantations, durian plantations, and avocado plantations. Both undisturbed and disturbed soil samples from each land use were analyzed to assess hydraulic conductivity, bulk density, and soil organic carbon (C) content. With the exception of wetland rice, all land uses exhibited a sandy loam texture. The forests contained the highest amount of SOC (4.70%), while the other samples contained less than half (2.01%) of this quantity.

Long-term impact of pulses crop rotation on soil fungal diversity in aerobic and wetland rice cultivation

Pulse crop rotation in rice cultivation is a widely accepted agronomic practice. Depending upon the water regime, rice cultivation has been classified into wetland and aerobic practices. However, no studies have been conducted so far to understand the impact of pulse crop rotation and rice mono-cropping on fungal diversity, particularly in aerobic soil. A targeted metagenomic study was conducted to compare the effects of crop rotations (rice-rice and rice-pulse) on fungal diversity in wetland and aerobic rice soils. Out of 445 OTUs, 41.80% was unknown and 58.20% were assigned to six phyla, namely Ascomycota (56.57%), Basidiomycota (1.32%), Zygomycota (0.22%), Chytridiomycota (0.04%), Glomeromycota (0.03%), and Blastocladiomycota (0.02%). Functional trait analysis found wetland rice-pulse rotation increased symbiotrophs (36.7%) and saprotrophs (62.1%) population, whereas higher pathotrophs were found in aerobic rice–rice (62.8%) and rice-pulse (61.4%) cropping system. Certain soil nutrients played a major role in shaping the fungal community; Ca had significant (p < 0.05) positive impact on saprotroph, symbiotroph and endophytes, whereas Cu had significant (p < 0.05) negative impact on pathotrophs. This study showed that rice-pulse crop rotation could enhance the saprophytic and symbiotic fungal diversity in wetland and reduce the population of pathogens in aerobic rice cultivation.

Rice Farming and the Origins of Cooperative Behaviour

Abstract This paper provides novel evidence for links between historic farming practices and current norms of cooperative behaviour. We hypothesise that the cooperation required in wetland rice farming gives rise to strong cultural norms of cooperativeness. We compare participants from prefecture cities that predominately practice wetland rice cultivation to those from non-rice regions. A public goods game with and without punishment is the main measure for cooperative behaviour. Results indicate a strong and robust positive effect of wetland rice farming on cooperative behaviour and pro-social punishment. Complementary, consistent evidence from a natural field experiment and a survey further enriches our data.

Mitigation Option for GHG Emission from Wetland Rice Cultivation

The study on the effect of soil amendments and fertilizers on the mitigation of CH4 and N2O emission from rice field was conducted in the Wetland farm of Tamil Nadu Agricultural University farm, Coimbatore, Tamil Nadu, India during rabi season. The results showed that the use of Gypsum and Fly Ash along with recommended dose of fertilizer reduced the emission of methane whereas urea with neem treatment reduced the N2O emission from the conventional water logged rice field. Methane emission was found to peak during the panicle initiation stage while nitrous oxide emission was noted only during the maturity stage. The application of Fly Ash along with gypsum had cut down the methane emission to a greater extent at all the stages. Nitrous oxide emission was reduced with the application of slow release N fertilizer (neem treated urea).

Selection of Sub1 Locus for Submergence-Tolerant Introgression in a Backcrossing of South Sumatra Rice based on SSR Markers

The development of a new submergence-tolerant variety is one ideal solution to reduce submergence stress impact caused by the unpredictable occurrence of flooding in the South Sumatra riparian wetland rice cultivation area. The Sub1 gene for submergence tolerance was introgressed into South Sumatra riparian wetland rice from the donor parent FR13A using marker-assisted backcrossing. This study involves a backcrossing between Pelita Rampak and BC1F1 Pelita Rampak, FR13A-derived Sub1 breeding lines. The main objective of this study was to introgress the Sub1 gene in BC2F1 using marker-assisted selection (MAS). The introgression of the Sub1 gene in the backcrossed lines was confirmed by the tightly linked markers RM219 and RM23915. The segregation ratio of RM219 was a good fit to the expected 1:1 Mendelian single-gene model (DF = 1.0, p ≤ 0.05). In the background study, out of 237 SSR markers unlinked to the target loci, 84 were found to be polymorphic between the two parents and were used for background selection among the selected progeny. Recurrent parent genome recovery in the backcrossed lines ranged from 57.1% to 72.6%. Improvements in the tiller number, percentage of filled grain, productive tiller number and percentage of tiller number were found on these backcrossed lines. The five best backcrossed lines were selected based on SSR markers, submergence tolerance, phenotypic study and agronomic performance.

Conservation Agriculture With Optimum Fertilizer Nitrogen Rate Reduces GWP for Rice Cultivation in Floodplain Soils

Wetland rice cultivation contributes significantly to global warming potential (GWP), an effect which is largely attributed to emissions of methane (CH4). Emerging technologies for wetland rice production such as conservation agriculture (CA) may mitigate greenhouse gas (GHG) emissions, but the effects are not well defined. Investigations were carried out in an irrigated rice (Boro rice) field in the fifth crop after conversion of conventional tillage (CT) to strip tillage (ST). Two crop residue levels (low versus high, LR versus HR) and three nitrogen (N) application rates (N1 = 108, N2 = 144, and N3 = 180 kg N ha−1) were laid out in a split-plot experiment with three replicates. Yield-scaled GHG emissions and GWP were estimated to evaluate the impacts of CA on mitigating CH4 and N2O emissions in the rice paddy field. There was a 55% higher N2O emission in ST with HR coupled with N3 than that in CT with LR coupled with N1. The N2O emission factors ranged from 0.43 to 0.75% in ST and 0.45 to 0.59% in CT, irrespective of the residue level and N rate. By contrast, CH4 emissions were significantly lower in CA than in the conventional practices (CT plus LR). The ST with LR in N2 reduced the GWP by 39% over the GWP in CT with HR in N1 and 16% over the conventional practices. Based on our investigation of the combination of tillage, residue, and N rate treatments, the adoption of CA with high and low residue levels reduced the GWP by 10 and 16%, respectively, because of lower CH4 and N2O emissions than the current management practices. The relatively high N2O emission factors suggest that mitigation of this GHG in wetland rice systems needs greater attention.

Diagnosis and management of green algae in low land paddy fields of Cauvery delta zone, Tamil Nadu

Rice is a prime food crop for Asian countries. Wet land rice cultivation contributes maximum grain yield than dry land rice. Cauvery delta is a predominant area for rice cultivation in Tamil Nadu. Green algae growth during Kuruvai (June -August) season is a serious problem in wet land rice. These algae growth create anaerobic condition and prevent rice root respiration. The entire rice root was uprooted and floated on the stagnated water during initial stage. There is no preliminary study for green algae control in rice field. Soil and water samples were collected and analyzed for the nature of occurrence. Laboratory and field experiments were conducted to find out the remedial measures. The results of soil and water sample analysis showed that use of bore well water and dumping of phosphatic fertilizers leads to salt accumulation which favours the green algal growth. The results of the laboratory experiment revealed that the CuSO4 londox power, propiconazole and hexaconazole showed moderate inhibition on 5th day after treatment. The findings from field experiment indicated that use of conoweeder, alternate wetting and drying and CuSo4 drenching @ of 2.5 kg/ha when green algae appearance has just noticed or 5.0 kg/ha when severe growth occurred was effective in managing the green algae. Among all measures, alternate wetting and drying is the best management practices. CuSO4 drenching reduces around 70% of the growth. Even though CuSO4 react negatively with algae growth, soil pH changes and salt concentration play a major role on the CuSO4 action towards green algae. In order to maintain soil health condition, biofertilizer application, crop rotation, green manure trampling to be practised to recover the soil from alkaline pH, removal of accumulated salt and to control the algae growth using CuSO4.

Rice Farming and the Origins of Cooperative Behavior

This paper provides novel evidence for links between historic farming practices and current norms of cooperation. We hypothesize that the cooperation required in wetland rice farming gives rise to strong cultural norms of cooperativeness. We compare participants from prefecture cities that predominately practice wetland rice cultivation, to those from non-rice regions. A public goods game with and without punishment is the main measure for cooperativeness. Results indicate a strong and robust positive effect of wetland rice farming on cooperation and pro-social punishment. Complementary, consistent evidence from a natural field experiment and a survey further enriches our data.

Modelling the diffusion and exchange of ammoniacal nitrogen following deep placement of urea supergranules in wetland rice cultivation

Deep placement of urea in the form of supergranules is often recommended in transplanted rice cultivation as a means of avoiding nitrogen loss in the environment. As ammoniacal nitrogen produced by urea hydrolysis just after deep application is chemically stable in the anaerobic layer of the paddy soil, it is relevant to study the diffusion–exchange phenomenon affecting this ammoniacal-N. More precisely, numerical calculus was called on to solve the nonlinear diffusion–exchange equation, admitting spherical symmetry in this context. The adsorption isotherm for ammoniacal-N intervening in this equation was a Freundlich isotherm. Experiments performed in the laboratory (untransplanted situation) and in the field (transplanted situation) enabled the monitoring of the time course of ammoniacal-N concentration in the central position. The tortuosity factor was evaluated at 0.80 in the paddy soil. In the field, the diffusion–exchange phase was clearly separated from the ammonia assimilation phase. The limit between the two was evaluated in six replicates. The first-order mechanism of ammonia disappearance is interpreted as the indication of a tight physiological regulation at the carbon–nitrogen interface acting within roots pushed to their limit in growth and assimilative capacity. This limit is here reported at 12 mM ammonia, attained 39 d after point application. This delay is enhanced when the tortuosity factor is reduced. Similar modelling in the context of cylindrical symmetry can be an option to study new urea fertilizers in the form of urea rods.

PERSEPSI PETANI TERHADAP SISTEM PERTANIAN ORGANIK DAN ANORGANIK DALAM BUDIDAYA PADI SAWAH

The purposes of this research were to determine the performance of organic and anorganic farming systems in wetland rice cultivation, rice farmers’ perception, the related factors to farmers' perception, the differences in rice farmers’ perceptions, and the constraints faced in that applications in Pajaresuk and Pujodadi Village. The data collection was conducted in November - December 2017. The research method used was census. The number of organic and anorganic rice farmers sampled were 35 farmers. The data was analyzed by descriptive analysis, Spearman rank correlation and the Mann-Whitney test. The results of this research show that the performance of organic and anorganic rice farming were land processing, seeding, planting, pest and disease controlling, fertilizating, irrigating, and harvesting. The differences performance of organic and anorganic rice farming were in seeding, pests and diseases controlling, and fertilizing. The rice farmers' perception to organic farming systems was quite good. The related factors to farmers' perception were social interaction, community support, and farmers' interests. There were no significant differences between organic farmers’ perceptions and the anorganic farmers’ perceptions. The constraint faced in the application of organic farming system was the difficulty of maintenance in cultivation, while in the application of anorganic farming systemwas the high costs, but the selling price was relatively low. Key words: anorganic rice, organic rice, perception

Integrated Effects of Poultry Manure and Chemical Fertilizer on Yield, Nutrient Balance and Economics of Wetland Rice Culture

Field trials were conducted for two years to evaluate the integrated effect of poultry manure (PM) and chemical fertilizers on yield, nutrient balance and economics of rice at BRRI, Gazipur (AEZ-28 and land type- High Land) during Boro 2009 to T. Aman 2010. Eight treatment combinations, where PM @ 1, 2, 3 t ha-1 with IPNS (Integrated plant nutrient system) based dose and PM @ 1, 2, 3 t ha-1 with 50% STB (soil test based) dose along with a control and 100% STB chemical fertilizer were tested. Immediate effects of manure and fertilizer were evaluated in Boro season and residual effects were observed in the following T. Aman season. Application of PM @ 2 t ha-1 with IPNS based chemical fertilizer or PM @ 3 t ha-1 with 50% STB dose gave higher grain yield in Boro season. Some residual effects in the succeeding T. Aman rice were observed where PM was used @ 3 t ha-1. The highest net return was obtained with 3 t PM ha-1 with 50% STB dose. A positive nutrient balance of phosphorus and sulfur were observed in PM and chemical fertilizer treated plots.&#x0D; Bangladesh Rice j. 2018, 22(2): 71-77

Efisiensi Produksi Usahatani Padi Sawah Kelompok Subak dan Non Subak di Kabupaten Kolaka

Pemanfaatan kearifan lokal dalam pengelolaan usahatani merupakan salah satu solusi dalam upaya untuk meningkatkan efisiensi usahatani. Salah satu bentuk kearifan lokal dalam pengelolaan usahatani padi sawah adalah subak, yang sampai saat ini masih dipertahankan oleh sebagian masyarakat yang berasal dari Pulau Bali di daerah perantauan. Masyarakat yang menerapkan sistem subak tersebut meyakini bahwa pengelolaan usahataninya lebih efisien dengan menerapkan sistem subak. Penelitian ini bertujuan untuk mengetahui pendapatan kelompok subak dan non subak dan keterkaitan antara sosio-kultural subak dengan pendapatan usahatani padi sawah. Pengumpulan data dilakukan dengan metode observasi, wawancara, dan studi literatur terhadap sampel/responden penelitian. Responden penelitian berjumlah 60, ditentukan secara purposive dan random. Analisis yang digunakan adalah analisis deskriptif statistik. Hasil penelitian menunjukkan bahwa pendapatan petani kelompok subak lebih besar dibandingkan petani non subak dengan rata-rata pendapatan sebesar Rp 12.672.686,67 untuk kelompok subak dan Rp 10.198.529,41 untuk kelompok non subak. Tidak ada hubungan yang terpola antara sosio-kultural dengan jumlah pendapatan oleh masing-masing petani responden baik subak maupun non subak, akan tetapi ada kecenderungan jika nilai skor sosio-kultural tinggi maka pendapatan yang diperoleh petani juga tinggi.

Analysis of energy use and greenhouse gas emissions (GHG) of transplanting and broadcast seeding wetland rice cultivation

The analysis of energy and greenhouse gas emissions in this study was made in respect to both planting methods, transplanting and broadcast seeding methods to investigate the energy pattern of rice production in Malaysia. The field under transplanting method in the main season showed 8.72% lesser mean total energy input, 6.25% higher mean machinery energy, 55.06% lesser mean seed energy and 23.01% higher mean output energy than the field under broadcasting method. Fertilizer the highest contributor of energy inputs it contributed by 62% in both transplanting and broadcasting methods and fuel was the second-highest contributor. The share of direct and indirect energy in the fields under the transplanting method were 19% and 81% and in the fields under the broadcasting method were 17% and 83% respectively. While the share of renewable and non-renewable energy in the fields under the transplanting method were 7% and 93% and in the fields under the broadcasting method were 14% and 86% respectively. The harvesting operation has the highest mechanization index level (0.99) in both methods. While fertilizing and planting operation have the lowest mechanization index level. The mean energy ratio was 35.68% higher in transplanting than broadcasting (8.1 and 5.97). Fertilizer represents the highest contributor to the total GHG emissions in the two cultivation methods, transplanting and broadcasting and it represents 44% and 42% respectively. Among different types of chemical fertilizers, Nitrogen represents the higher contributor.

Rotary tillage effects on some selected physical properties of fine textured soil in wetland rice cultivation in Malaysia

The aim of this study was to investigate the effects of short-term repeated passes tillage operations on bulk density, soil penetration resistance, soil porosity and the moisture of a clay loam soil of Malaysia. A field experiment for three seasons was conducted at Sungai Burong Tanjung Karang Kuala Selangor, Malaysia to study treatments consisting of (I) no-tillage NT (II) first tillage FT (III) second tillage (ST), (IV) third tillage (TT) operations. The soil bulk density, soil penetrometer resistance, pore distribution, and moisture content characteristics were determined before and after for each of the three tillage. The penetration resistance was determined at the depths of 0–80 cm while the soil moisture was determined on the surface (0–20 cm). These properties were determined directly before and after tillage operations. All the tillage operations were significantly different in their effects on soil bulk density and soil penetration resistance. The soil bulk density decreased with the degree of soil manipulation after first and third tillage and increased after second tillage, with NT having the highest mean bulk density 1.04, 0.95 and 1.03 g/cm3 while TT having the least 0.84, 0.83 and 0.72 g/cm3 for 1st, 2nd and 3rd season respectively. The soil penetration resistance decreased due to tillage operation, with NT also having the highest resistance of 1.69 MPa and 1.44 Mpa in hardpan during 1st and 2nd season and the lowest PR was 0.09, 0.17 and 0.21 Mpa at TT in 1st, 2nd and 3rd season. Highest mean porosity was 0.68 in 2nd season at TT and the lowest mean porosity was 0.36 in 3rd season at NT. The lowest volumetric moisture content was at ST 0.26 and 0.27 in 1st and 2nd season at ST, and the highest was at TT 0.56, 0.57 and 0.68 at TT in 1st, 2nd and 3rd season respectively. The soil particle density was increased after three tillage operation. The highest increase (23.73%) was noted in FT 2nd season and the minimum was in TT in 1 st season (6.04%) while it decreased in ST during the three seasons.

FENOMENA BERBAGAI SIFAT FISIKA DAN KIMIA TANAH MENDUKUNG KETAHANAN TANAMAN PANGAN DI SUMATERA BARAT

The objective was to examine the phenomenon of physical and chemical properties of soil which is used as a center of agricultural cultivation in supporting food security in West Sumatra. The experiment was conducted by survey to various locations by taking composite soil samples in the field. Some types of soil taken include Histosol from Anai Padang Pariaman; Ultsiol from Lubuk Minturun; Inceptisol from Limau Manis and Siteba city of Padang; Andisol from Danau Kembar and Lembah gumanti Kab. Solok. The result was can be concluded that Ultisol Lubuk Minturun more potency for tropical fruits. Andisol in Lembah Gumanti and Danau Kembar Kab. Solok has decreased its chemical quality. It is necessary to increase soil pH to be suitable for the development of vegetable crops and food crops. The use of lime and organic matter in a proper fertilizing package can reduce the use of heavy fertilizer for vegetable crops and horticultura. Histosol utilization for wetland rice cultivation needs to be careful because the acidic pH and the number of organic acids are toxic. Inceptisol Limau Manis Padang has a neutral pH, and is very good for developing food cultivation in support of food security in West Sumatra.

Comparative field performances between conventional combine and mid-size combine in wetland rice cultivation

In paddy cultivation, harvesting is the most important operation, which needs suitable machinery. Thus, this study was carried out to compare field performances and energy and environmental effect between the conventional 5 m cutting width NEW HOLLAND CLAYSON 8080, 82 kW@2500 rpm combine harvester running on a total net area of 42.78 ha of plots for two rice (Oryza sativa L.) cultivation seasons and the new mid-size 2.7 m cutting width WORLD STAR WS7.0, 76 kW@2600 rpm combine harvester running on a total net area of 16.95 ha of plots for two rice cultivation seasons. The conventional combine as compared to mid-size combine showed 14.4% greater mean fuel consumptions (21.13 versus 18.46 l/ha), 31.1% greater mean effective field capacity (0.69 versus 0.53 ha/h), 5.23% greater cornering time (turning time) percentage of total time (8.28% versus 3.05%) and 1.41% greater reversing time percentage of total time (7.2% versus 5.79%) but 20.90% lesser mean operational speed (3.24 versus 4.10 km/h), 11.69% lesser effective time percentage of total time (60.0%versus 71.69%h/ha), 10.8% lesser mean field efficiency (64.3% versus 72.1%). In terms of total energy use the conventional combine showed 24.64% greater mean total energy use in the harvesting operation (1445.81 versus 1160.00 MJ/ha), 14.46% greater mean fuel energy (1010.014 versus 882.39 MJ/ha), 56.47% greater mean machinery energy (431.32 versus 275.65 MJ/ha) and 59.25% greater mean human energy (3.48 and 2.18 MJ/ha), this cause 26.12% greater mean total Green House Gas emission (GHG) than the mid-size combine. The results revealed that the mid-size combine is more suitable in conducting the harvest operation in rice field in Malaysia than the conventional combine.

Field evaluations of agrochemical toxicity to cyanobacteria in rice field ecosystem: a review

The adverse effects of chemical nitrogen fertilizers affecting soil fertility, water pollution and native microorganisms, particularly cyanobacteria, in wetland rice cultivation have drawn global attention towards the use of alternative sources like N2-fixing cyanobacteria as a biofertilizer for sustainable rice farming. Although chemical nitrogen fertilizers are extensively used for obtaining higher rice yield, they are likely to have a deleterious effect on the growth and N2-fixation of diazotrophs, including cyanobacteria. In addition, biocides (herbicides and insecticides) are widely being used in rice cultivation for optimizing crop yield, but these chemicals also affects non-target organisms adversely. There are several reports indicating impacts of these agrochemicals on cyanobacteria, but most such studies were carried out under laboratory conditions. This article reviews information from different field evaluations on the impact of agrochemicals on cyanobacteria along with rice crop in wetland rice field ecosystem.