Aerobic Rice Research Articles

Generation Mean Analysis in Physio-morphic Traits of Aerobic Rice in Assam, India

An experiment was carried out to study the genetic architecture of few physio-morphic quantitative traits of rice under aerobic condition. Generation mean analysis was carried out in three selected crosses viz.Banglami/Luit, Koimurali/Luit and Guni/Gopinath, involving six generations (P­1, P2, F1, F2, BC1 and BC2) at the experimental farm of SCS college of Agriculture, Assam Agricultural University, Dhubri, Assam, India during 2017 and 2018. The individual scaling tests were used to test the adequacy of additive dominance model. The gene effects were estimated using three parameter models (joint scaling test) suggested by Cavalli (1952) and six parameter model suggested by Haymen (1958). The analysis of variance among different generations of different crosses revealed significant variation for most of the characters indicating considerable variability in the material studied. All the characters except height growth rate in cross II, recorded significance for at least one of the four individual scaling tests in all the 3 crosses. Estimation of different gene effects and their interactions were done in OPSTAT software. Significant positive additive effects were recorded for plant height and height growth rate for in all the three crosses. Preponderance of dominance effect in the expression of height growth rate, spikelet fertility, grain yield, harvest index, root weight and root shoot ratio was evident from the significant positive dominance (h) effect in all the three crosses. With respect to interaction effects, all the characters except height growth rate in cross II, exhibited significant interaction effect for one or more epistatic interactions i.e.[i], [j] or [l] in all the three crosses studied. It is evident that for all the yield and other adaptive traits, additive, dominance and interaction effects were present indicating the complex inheritance of the traits under aerobic condition. Hence, focus should be on improving individual characters separately based on the nature of gene action.

Soil test crop response nutrient prescription equations for improving soil health and yield sustainability—a long-term study under Alfisols of southern India

IntroductionEnhancing soil health and nutrient levels through fertilizers boosts agricultural productivity and global food security. However, careful fertilizer use is essential to prevent environmental damage and improve crop yields. The soil test crop response (STCR) is a scientific approach to fertilizer recommendation that ensures efficient use, supporting higher crop production while protecting the environment and preserving resources.MethodologyA long-term field experiment on the STCR approach was initiated in 2017 at the Zonal Agriculture Research Station, University of Agricultural Sciences, Bangalore, India. The experiment aimed to study the impact of STCR-based nutrient prescription along with farmyard manure (FYM) for a targeted yield of soybean (Glycine max), sunflower (Helianthus annuus), dry chili (Capsicum annuum), aerobic rice (Oryza sativa L.), foxtail millet (Setaria italica), okra (Abelmoschus esculentus), and kodo millet (Paspalum scrobiculatum) on yield and changes in soil health in comparison with other approaches of fertilizer recommendation.ResultsThe results showed a significant and positive impact of the integrated use of fertilizer with FYM based on the STCR approach on the productivity of all the crops and soil fertility. Significantly higher yields of soybean (23.91 q ha−1), sunflower (27.13 q ha−1), dry chili (16.67 q ha−1), aerobic rice (65.46 q ha−1), foxtail millet (14.07 q ha−1), okra (26.82 t ha−1), and kodo millet (17.10 q ha−1) were observed in the STCR NPK + FYM approach at yield level 1 compared to the general recommended dose and soil fertility rating approach. This approach outperformed the standard recommendations, enhancing nutrient uptake and efficiency across various crops. Utilizing the principal component analysis, the soil quality index effectively reflected the impact of nutrient management on soil properties, with the STCR NPK + FYM treatment at yield level 1 showing the highest correlation with improved soil physical and chemical parameters.DiscussionThe STCR approach led to improved yield, nutrient uptake, utilization efficiency, and soil health, thanks to a balanced fertilization strategy. This strategy was informed by soil tests and included factors like crop-induced nutrient depletion, baseline soil fertility, the efficiency of inherent and added nutrients through fertilizers and farmyard manure, and the success of yield-targeting techniques in meeting the nutritional needs of crops.

Soil greenhouse gas emissions under enhanced efficiency and urea nitrogen fertilizer from Australian irrigated aerobic rice production

AbstractAerobic rice production offers a promising solution to improve water use efficiency and reduce methane (CH4) emissions by minimizing water inundation. However, alternate water‐saving methods for rice cultivation can lead to “trade‐off” emissions of nitrous oxide (N2O). A field experiment was conducted over one season measuring soil‐derived greenhouse gas emissions in irrigated aerobic rice (Oryza sativa L.) under different N fertilizer management at a rate of 220 kg N ha−1, including a nil treatment (“control”); slow release (180 days) polymer‐coated urea (“N180”); banded urea applied upfront (“urea”); and three applications of broadcast urea (“urea‐split”). The N180 treatment reduced soil N2O emissions compared with urea (p < 0.001), with mean cumulative N2O emissions of 4.36 ± 1.07 kg N ha−1 and 27.9 ± 5.70 kg N ha−1, respectively. Soil N2O fluxes were high, reaching up to 1916 and 2900 µg N m2 h−1 after urea application and irrigation/rain events, and were similar to other irrigated crops grown on heavy textured soils. Fertilizer N management had no effect on soil CH4 emissions, which were negligible across all treatments ranging from 1.28 to 2.75 kg C ha−1 over the growing season. Cumulative soil carbon dioxide emissions ranged from 1936 to 3071 kg C ha−1 and were greatest in N180. This case study provides the first evidence in Australia that enhanced efficiency nitrogen fertilizer can substantially reduce N2O emissions from soils in an aerobic rice system. Our findings reinforce the CH4 mitigation potential of water saving rice approaches and demonstrate the need to consider N fertilizer management to control N2O emissions.

Eco-friendly green synthesised nano iron particles from weed leaf extract: a potential nutritional source for enhancing the germination and yield of aerobic rice

Eco-friendly green synthesised nano iron particles from weed leaf extract: a potential nutritional source for enhancing the germination and yield of aerobic rice

Effect of Different Fertilizers and Approaches on Nutrient Use Efficiency and Economics of Aerobic Rice Under Rice-Cowpea Cropping Sequence in Ecological Conditions of Karnataka, India

At the University of Agricultural Sciences, GKVK, Bengaluru, a field experiment was conducted in 2015-16 and 2016-17 to examine the impact of fertigation on the yield, nutrient usage efficiency, and economics of aerobic rice in an aerobic rice–cowpea cropping sequence. In a randomized block design, hybrid rice was tested in aerobic conditions with 16 treatments that were reproduced three times. The results indicated that significantly higher grain (62.98 q ha-1) and straw (85.26 q ha-1) yield of rice was recorded in 100% STCR dose through WSF at 8 DI. Similarly higher NRn (3.50 kg q-1) and NRp (0.86 kg q-1) of grain production in 100% STCR dose with WSF at 8 DI on contrary, higher NRk of 2.27 kg q-1 was noticed in 100% STCR with WSF at 4 DI. While higher AUE-N (32.51 kg kg-1), AUE-P (65.02 kg kg-1) and AUE-K (65.02 kg kg-1) were recorded in 30% RDF with WSF at 8 DI. The higher ACRE-N (78.60 %) was recorded with 100% RDF with WSF at 8 DI and higher ACRE-P (44.40%) was recorded with 30% RDF with WSF at 8 DI. Notably higher ACRE-K (132.51%) was recorded in 30% STCR with WSF at 8 DI. However, supplement of 30% STCR dose with WSF at 8 DI obtained notably higher IUE-N (35.05 kg kg-1), IUE-P (163.27 kg kg-1) and IUE-K ( 60.11 kg kg-1). Significantly higher PFP-N, P and K (261.23, 522.46 and 522.46, respectively) were recorded in 30% RDF with WSF at 8 DI. Among all treatments, 100% RDF through CF at 4 DI found significantly higher B: C ratio (2.74) during both years of pooled data.

Impact of Conservation Tillage and Nitrogen Management on Soil Temperature and Soil Moisture in Aerobic Rice

This study investigates the impact of different tillage practices, namely Conventional Tillage (CT) (T1), Minimum Tillage with residue retention (MT) (T2) and Zero Tillage (ZT) (T3) and nitrogen fertilizer schedules 100% RDN (N1) (120 kg ha-1), 100% RDN + foliar spray of nano urea 2.5 ml l-1 at active tillering and panicle initiation stage (N2), 100% RDN + foliar spray of nano DAP 2.5 ml l-1 at active tillering and panicle initiation stage (N3), 75% RDN + Nano urea 2.5 ml l-1 at active tillering and panicle initiation stage (N4), 75 % RDN + Nano DAP 2.5 ml l-1 at active tillering and panicle initiation stage (N5) on soil temperature, moisture and their interaction in aerobic rice cultivation. Soil temperature was measured using digital thermometer and soil moisture was determined by Owen drying method. Results revealed that soil temperature and soil moisture was significantly influenced by tillage practices and Nitrogen fertilizer schedules showed no significant effect on soil temperature and soil moisture. Zero tillage (T3) consistently recording the lowest soil temperatures compared to T1 and T2 in both years. During rabi 2022-2023, T3 recorded 18.23°C in the 1st week, significantly lower than T1 (19.32°C). This trend persisted in the rabi 2023-2024, with T3 recording 27.1°C in the 19th week, significantly lower than T1 (28.61°C). In terms of soil moisture, zero tillage (T3) also consistently resulted in the highest moisture levels. During rabi 2022-2023 season, T3 recorded 18.93% soil moisture in the 1st week, significantly higher than T1 (18.11%). This pattern continued in the rabi 2023-2024, with T3 maintaining significantly higher moisture levels in most weeks. Zero tillage is effective in reducing soil temperature and enhancing soil moisture retention. Minimum tillage with residue retention performing similar to zero tillage.

Evaluating the Performance of Rice in Different Intercropping Systems under Aerobic Rice Cultivation

Evaluating the Performance of Rice in Different Intercropping Systems under Aerobic Rice Cultivation

Influence of nano fertilizers on productivity and profitability of aerobic rice in Eastern dry zone of Karnataka

Influence of nano fertilizers on productivity and profitability of aerobic rice in Eastern dry zone of Karnataka

Impact of ready-mix herbicides on weed growth and yield of aerobic rice under trickle irrigation

Impact of ready-mix herbicides on weed growth and yield of aerobic rice under trickle irrigation

Nitrogen Uptake and Use Efficiency of Aerobic Rice as Affected by Different Nitrogen Management: A Review

Nitrogen Uptake and Use Efficiency of Aerobic Rice as Affected by Different Nitrogen Management: A Review

Understanding the leaf rolling of paddy and exploring its management options under aerobic rice

Rice is a staple food in the diets of more than half of the world's population. With India's irregular rainfall patterns and continual environmental anomalies, particularly in Kerala, the identification of climate-smart management practices which can withstand drought is critical. In this context, atrial was conducted in the experimental plots to evolve effective water and nutrient management practices under aerobic rice in lateritic soils of Kerala. However, during the experiment in a few treatments, rolling of leaves was observed, and when explored for the reasons, it was due to soil moisture deficit and plant water stress. When compared to other crop species, rice is highly vulnerable to water deficit. In this regard, an attempt has been made to study the leaf rolling pattern in aerobic rice and how this can be managed with a few soil amendments so that rice productivity can be sustained. The results showed that plant growth parameters, relative water content (RWC), membrane leakage (ML) and spectral signatures were significantly affected by the leaf rolling. It was found that leaf rolling affected plants have less RWC and higher ML and are under drought stress. Pearson correlation analysis showed a strong positive correlation (P < 0.05) of key spectral indices with other physiological traits such as RWC and negatively correlated with ML. Moisture absorbent media such as cocopeat, compost, saw dust and vermiculite were attempted as management strategies to overcome this stress. Results showed that among the absorbents attmepted, cocopeat was found to be better in managing the stress. These results suggest that for aerobic rice under lateritic soil, moisture absorbent media such as cocopeat, has to be incorporated so that it can reduce the rate of leaf rolling thereby sustaining the paddy yield.

IoT-Integrated drip irrigation and fertigation for improving root and physiological metrics in aerobic rice

IoT-Integrated drip irrigation and fertigation for improving root and physiological metrics in aerobic rice

Root parameters and water productivity of rice and wheat in a rice‒wheat cropping system as influenced by enriched compost and crop establishment methods

Food security worldwide is largely dependent on the rice–wheat cropping sequence (RWCS) Hence, a field study was carried out during 2018–19 and 2019–20 at ICAR-IARI, New Delhi, to determine the effect of various enriched organic sources and crop establishment methods on the root parameters, water productivity and yield of rice, its carryover effect on the succeeding wheat crop and the overall efficiency of system. A split plot design was used which involved two main plot treatments, viz., aerobic rice (AR) and conventional transplanted (CT) rice, and five subplot treatments, viz., T1: control (without fertilizer), T2: 100 % RDF (100 % fertilization by using inorganic sources), T3: 50 % phosphorus was applied by using P-enriched compost + 50 % P was applied by using DAP, T4: 50 % N was applied by using N-enriched compost + 50 % nitrogen was applied by using DAP and urea, and T5: 100 % organic fertilizer was applied (100 % fertilization by using N-enriched compost and P-enriched compost). After rice, wheat was grown in all the plots under uniform management practices. Among the nutrient sources, T4 had greater effects on root activity, system economic water productivity and system water productivity than did the other treatments. CT rice can be recommended under irrigated conditions with the integration of enriched compost and inorganic fertilizers. However, under rainfed conditions with less available water, aerobic rice can also be produced by combining enriched compost and inorganic fertilizer.

Water-fertilizer regulation drives microorganisms to promote iron, nitrogen and manganese cycling: A solution for arsenic and cadmium pollution in paddy soils

The co-contamination of arsenic (As) and cadmium (Cd) in rice fields presents a global imperative for resolution. However, understanding the complex microbially driven geochemical processes and network connectivity crucial for As and Cd bioavailability under the frequent redox transitions in rice fields remains limited. Here, we conducted a series of microcosm experiments, using flooding and drainage, alongside fertilization treatments to emulate different redox environment in paddy soils. Soil As significantly reduced in drained conditions following applications of biochar or calcium-magnesium-phosphate (CMP) fertilizers by 26.3 % and 31.2 %, respectively, with concurrent decreases in Cd levels. Utilizing geochemical models, we identified the primary redox cycles dynamically altering during flooding (Fe and S cycles) and drainage (Fe, Mn, and N cycles). PLS-SEM elucidated 76 % and 61 % of the variation in Cd and As through Mn and N cycles. Functional genes implicated in multi-element cycles were analyzed, revealing a significantly higher abundance of assimilatory N reduction genes (nasA, nirA/B, narB) in drained soil, whereas an increase in ammonia-oxidizing genes (amoA/B) and a decrease in nitrate reduction to ammonium genes were observed after CMP fertilizer application. Biochar application led to significant enrichment of the substrate-binding protein of the Mn transport gene (mntC). Moreover, Fe transport genes were enriched after biochar or CMP application compared to drained soils. Among 40 high-quality metagenome-assembled genomes (MAGs), microbial predictors associated with low Cd and As contents across different treatments were examined. Bradyrhizobacea harbored abundant Mn and FeIII transport genes, while Nitrososphaeraceae carried nitrification-related genes. Two MAGs affiliated with Caulobacteraceae, carrying diverse Fe transport genes, were enriched in biochar-applied soils. Therefore, applying CMP fertilizer or biochar in aerobic rice fields can synergistically reduce the bioavailability of Cd and As by specifically enhancing the circulation of essential elements.

Influence of microbial consortia mediated in-situ rice straw management options on yield, economics and energetics in rice-wheat cropping system

A field experiment was carried out during rainy and winter seasons of 2019–20 and 2020–21 at ICAR-IARI, New Delhi to study the effect of crop establishment methods and microbial consortia (Pusa decomposer) mediated in-situ rice straw management options on yield, economics and energetics of rice (Oryza sativa L) (cv. Pusa Basmati 1509) and wheat (Triticum aestivum L.) (cv. HD 2967). The experiment was laid out in split-plot design with three replications. The main plot consisted of two treatments viz., aerobic rice (AR) and conventional transplanted (CT) rice in wet season and seven sub-plot treatments viz. clean cultivation (removal of paddy straw), paddy straw incorporation (PSI), paddy straw mulching (PSM), PSI + Pusa decomposer (PD), PSM + PD, PSI + urea @ 20 kg/ha, PSI + PD + urea @ 10 kg/ha in dry season. In rice, results showed that grain yield (4.23 and 4.42 t/ha), net return (`69,470 and `71,682/ha) and energy output (157361 and 160950 MJ/ha) were significantly superior in CT rice than AR in main plots during both the years of experiment. However, sub-plot treatments showed a non-significant difference on these parameters. In wheat, among in-situ rice straw management options, paddy straw incorporation+ Pusa decomposer + urea @ 10 kg/ha treatment significantly resulted in higher grain yield (4.86 and 4.92 t/ha), net return (`62697 and `64801 /ha) and energy output (174951 and 176730 MJ/ha) compared to other treatments and control (clean cultivation). However, in main plots, statistically similar results were obtained with AR-wheat and CT-wheat. Thus, conventional rice transplanting resulted in significantly higher productivity and profitability over aerobic rice, however, AR consumed less energy (18.95%) and water (31.73%). Whereas, paddy straw incorporation+ Pusa decomposer + Urea @ 10 kg/ha was found effective in-situ rice management options with higher productivity and energy output compared to control.

Exploring drought mitigation options for improvement of physiology, yield and water use efficiency of aerobic rice (Oryza sativa)

An experiment was conducted during summer seasons of 2022 and 2023 in Wetland Farms at Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu to mitigate the ill effects of moisture stress during the flowering stage of rice (Oryza sativa L.) by moisture stress mitigating chemicals. The trial was laid out in split plot design (SPD) with 3 main plots and 4 sub-plots, and replicated thrice. In main plot, irrigation at IW/CPE ratio 1.0 from emergence to physiological maturity (M1); withholding irrigation (drought stress) for 8 days from heading stage (M2); and withholding irrigation (drought stress) for 12 days from heading stage (M3) and in sub-plot drought stress mitigating chemicals, viz. no spray (S1); salicylic acid spray @100 ppm (S2); sodium selenate @20 ppm (S3); and pink pigmented facultative methylotrophs (PPFM) @1% (S4) were tested. Results revealed that irrigation at IW/CPE 1.0 from crop emergence to physiological maturity along with foliar spray of selenium @20 ppm at heading stage had beneficial impact on growth, physiological parameters, yield attributes and yield. Drought stress given for 8 days from heading stage with selenium spray recorded lesser detrimental effect on growth characters, yield attributes and yield when compared to drought stress given for 12 days from heading stage in aerobic rice cultivation. The yield reduction in drought stress for 12 days from heading stage with selenium @20 ppm spray and drought stress for 8 days from heading stage with selenium @20 ppm spray were 23.6 and 16.5% respectively, when compared to irrigation at IW/ CPE ratio 1.0 from crop emergence to physiological maturity with selenium spray @20 ppm. Water use efficiency and water profitability also increased by the application of stress mitigating chemical of sodium @20 ppm. From this study, it is recommended that, in aerobic rice cultivation if there is any drought occurrence during heading stage of crop, the selenium application @20 ppm can withstand drought even up to 8 days from heading stage.

The microsprinkler irrigation system influences the growth, yield, and water productivity and nutrient uptake of aerobic rice under humid subtropical climatic conditions

The microsprinkler irrigation system influences the growth, yield, and water productivity and nutrient uptake of aerobic rice under humid subtropical climatic conditions

The Impact of Water-Saving Irrigation on Rice Growth and Comprehensive Evaluation of Irrigation Strategies

To explore the effects of different water-saving treatments on rice plant growth and select suitable water-saving irrigation strategies for aerobic rice varieties, we conducted relevant field experiments from June to October 2023 at Jiangsu Runguo Agricultural Development Co., Ltd., China, which is located in a north subtropical monsoon climate where the soil is alkaline sandy loam. Four water treatments were set up, including the control of local conventional irrigation (CK, without water stress), mild water-saving treatment (W1, 20% more water saved than CK), moderate water-saving treatment (W2, 30% more water saved than CK), and severe water-saving treatment (W3, 40% more water saved than CK). The experiment results showed that rice plant heights were inhibited and leaf chlorophyll contents increased under all water-saving treatments compared to CK. Among them, the MDA content in paddy leaves under the W1 treatment decreased, while the activities of SOD and POD were enhanced and the membrane lipid peroxidation capacity of rice was also enhanced. Meanwhile, the results showed that the rice yield and quality under the W1 treatment significantly improved. Based on those experiments, a comprehensive evaluation of rice plant height, chlorophyll content, grain yield, yield components, and rice quality was conducted using the TOPSIS entropy weight method. It was preliminarily concluded that the suitable irrigation scheme for south and central Jiangsu was 20% water-saving irrigation compared with CK. In summary, under the premise of maintaining the economic yield of rice cultivation, an appropriate water irrigation plan helped save water resources and promote rice growth.

Optimizing nitrogen and potassium for aerobic rice (Oryza sativa L.) in elevated -temperature environments

Optimizing nitrogen and potassium for aerobic rice (Oryza sativa L.) in elevated -temperature environments

Effect of Crop Establishment Methods and Weed Management Practices on Productivity and Bioenergetics of Rice

Background: SRI and aerobic rice are one of the techniques of growing rice under water scarcity areas where meeting water requirement is becoming a global threat. Weeds are another threat to yield of rice irrespective of different establishment methods. Until checked, it can decline rice yield and quality up to more than 70%. SRI and aerobic rice have different densities of weeds and integrated weed management can be applied to suppress the weeds. Considering the current scenario, research was conducted to investigate growth, yield and bioenergetics of rice under different establishment methods and weed management. Methods: The experiment entitled “Effect of crop establishment methods and weed management practices on productivity and bioenergetics of rice” was carried out in split plot design with main plots, viz., M1- aerobic rice (AR) and M2- system of rice intensification (SRI) and five subplots W1- pre-emergence (pendimethalin @1 kg a.i ha-1) fb post-emergence (bispyribac-sodium @20g a.i ha-1) (PE+POE), W2- pre-emergence (pendimethalin @1 kg a.i ha-1) fb cono weeding at 15, 30, and 45 DAT/ DAS (PE+CW), W3- weed free (WF), W4- weedy check (WC), W5- stale seedbed followed by post-emergence herbicide (bispyribac-sodium 10% SC 20 g a.i ha-1) (SSB+POE) in split plot design with three replications taking the variety ‘Pusa Basmati-1121’ as a test crop. Result: Among the establishment methods, SRI recorded significantly higher growth attributes like plant height and dry matter production and yield attributes like number of panicles per hill, panicle length, number of grains per panicle, test weight, grain yield, straw yield, biological yield, and harvest index. Among the weed management treatments, WF recorded significantly higher growth attributes like plant height, number of tillers per hill, dry matter production and yield attributes like number of panicles per hill, panicle length, number of grains per panicle, test weight, grain yield, straw yield, biological yield, and harvest index that was followed by treatment PE+CW. Maximum net return and B:C ratio was observed in the treatment combinations M2W2- SRI + (PE+CW). The maximum total energy input was found in the treatment combination M1W1- AR+ (PE+POE) and the maximum total energy output was found in the treatment combination M2W3- SRI + WF. The energy intensiveness was observed to be maximum in the treatment combination M1W4- AR + WC and the maximum energy efficiency index was observed in the treatment combination M2W3- SRI+WF.