Use Efficiency Of Rice Research Articles

An integrated transcriptome and physiological analysis of nitrogen use efficiency in rice (Oryza sativa L. ssp. indica) under drought stress

An integrated transcriptome and physiological analysis of nitrogen use efficiency in rice (Oryza sativa L. ssp. indica) under drought stress

Contrasting Alleles of OsNRT1.1b Fostering Potential in Improving Nitrogen Use Efficiency in Rice.

Nitrogen use efficiency (NUE) is important for the growth and development of rice and is significant in reducing the costs of rice production. OsNRT1.1b is involved in nitrate assimilation, and the alleles at position 21,759,092 on chromosome 10 clearly separate indica (Pathum Thani 1 (PTT1) and Homcholasit (HCS)) and japonica (Azucena and Leum Pua (LP)) rice varieties. Rice morphological and physiological traits were collected at three nitrogen levels (N0 = 0 kg ha-1, N7 = 43.75 kg ha-1, and N14 = 87.5 kg ha-1). Leaf and tiller numbers in PTT1 and HCS at N7 and N14 were two to three times higher than those at N0. At harvest, the biomass yield in PTT1 was the highest, while the total grain number in HCS was the maximum. The leaf widths and total chlorophyll contents (SPAD units) of Azucena and LP increased with nitrogen application as well as photosynthetic pigment parameters; for example, plant senescence reflectance indices (PSRIs), structure-insensitive pigment indices (SIPIs), and modified chlorophyll absorption ratio indices (MCARIs) were highly related in the japonica varieties. PTT1 and HCS, both carrying the A allele at OsNRT1.1b, had better NUE than Azucena and LP with the G allele. HCS, overall, had better NUE than PTT1. The translation to grain yield of assimilates was remarkable in PTT1 and HCS compared with Azucena and LP. In addition, HCS converted biomass for a 75% higher yield than PTT1. The ability of HCS to produce high yields was achieved even at N7 nitrogen fertilization, manifesting efficient use of nitrogen.

Water Use Efficiency in Rice Under Alternative Wetting and Drying Technique Using Energy Balance Model with UAV Information and AquaCrop in Lambayeque, Peru

In the context of global warming, rising air temperatures are increasing evapotranspiration (ETc) in all agricultural crops, including rice, a staple food worldwide. Simultaneously, the occurrence of droughts is reducing water availability, affecting traditional irrigation methods for rice cultivation (flood irrigation). The objective of this study was to determine ETc (water use) and yield performance in rice crop under different irrigation regimes: treatments with continuous flood irrigation (CF) and irrigations with alternating wetting and drying (AWD5, AWD10, and AWD20) in an experimental area in INIA–Vista Florida. Water balance, rice physiological data, and yield were measured in the field, and local weather data and thermal and multispectral images were collected with a meteorological station and a UAV (a total of 13 flights). ETc values obtained by applying the METRICTM (Mapping Evapotranspiration at High Resolution using Internalized Calibration) energy balance model ranged from 2.4 to 8.9 mm d−1 for the AWD and CF irrigation regimes. In addition, ETc was estimated by a water balance using the AquaCrop model, previously parameterized with RGB image data and field weather data, soil, irrigation water, and crops, obtaining values between 4.3 and 7.1 mm d−1 for the AWD and CF irrigation regimes. The results indicated that AWD irrigation allows for water savings of 27 to 28%, although it entails a yield reduction of from 2 to 15%, which translates into an increase in water use efficiency (WUE) of from 18 to 36%, allowing for optimizing water use and improving irrigation management.

Involvement of plasma membrane H+-ATPase in the nitrate-nutrition uptake and utilization in indica rice

Utilization of nitrogen by crops is essential for sustainable agriculture. The transport of nitrate (NO3−) across the plasma membrane is a critical gateway for N uptake and subsequent utilization. This process requires proton (H+) coupled cotransport, which is driven by proton motive force, provided by plasma membrane (PM) H+-ATPase. In this report, two indica rice varieties [Meixiangzhan 2 (MXZ) and Jifengyou 1002 (JFY)] in South China were selected and cultivated in hydroponic solution with 0.5 mM or 2.0 mM NO3− as the N source. The JFY exhibited stronger growth with higher biomass than MXZ under both 0.5 mM and 2.0 mM NO3−. PM H+-ATPase activity of JFY roots was significantly higher than that of MXZ. The higher PM H+-ATPase activity in JFY was consistent with a higher abundance of PM H+-ATPase protein and higher transcription levels of OSAs, such as OSA2, OSA7 and OSA8 in roots, OSA3, OSA7 and OSA8 in leaves. The expression of nitrate transporters (OsNRT1;1b, OsNRT2.1, OsNRT2.2, and OsNAR2.1) were also higher in roots or shoots of JFY than those in MXZ. Under 0.5 mM and 2.0 mM NO3−, the NO3− absorption and translocation rate, nitrate content, as well as nitrate reductase (NR) activity were all significantly higher in JFY, as compared to those in MXZ. Taken together, in JFY and MXZ, a higher level of PM H+-ATPase protein and higher activity coupled with greater efficiency in nitrate uptake, translocation and assimilation, suggesting the existence of a close correlation between PM H+-ATPase and nitrate utilization in indica rice. PM H+-ATPase may one of the elite genes that can contribute to nitrate use efficiency in rice.

Impact of nitrogen and potassium management on growth, nutrient uptake and nutrient use efficiency of rice under semi dry condition

The current study was aimed to search effect of nitrogen doses and time of application on performance of semi dry rice. The field experiment was conducted at College of Agriculture,(V. C. Farm), Mandya, University of Agricultural Sciences, Bengaluru during kharif 2019 and 2020, which comes under Southern Dry Zone of Karnataka (Zone-VI) to study the response of semi dry rice on growth and nutrient use efficiency under two doses of nitrogen and potassium doses (100% RDNK, 125%RDNK) as main treatments and seven time of application as sub treatments.The result revealed that higher SPAD meter reading (37.77) and nutrient uptake (77.90, 27.98 and 24.14 kg ha-1)was seen in 125% RDNK and higher nitrogen and potassium use efficiency was observed in 100%RDNK (49.30, and 98.59 kg kg-1 nutrient applied respectively). Where as in split application, higher SPAD meter reading (38.90), nutrient uptake (81.82, 29.57 and 25.35kg ha-1)and nutrient use efficiency (49.86, 11.33 and 99.73 kg kg-1 nutrient applied respectively) was recorded in N at 4 splits as, 25% each at sowing, early tillering, tillering and panicle initiation, K at 2 splits (50% at basal and 50% at panicle initiation) compared to rest of the application. Hence application of application of 125% RDNK, N at 4 splits as, 25% each at sowing, early tillering, tillering and panicle initiation, K at 2 splits (50% at basal and 50% at panicle initiation) is the appropriate time for rice production Southern Dry Zone of Karnataka.

Optimization of phosphorus and potassium use efficiency of rice (Oryza sativa L) under different flood depths within the Everglades Agricultural Area

Rice cultivation in South Florida, especially within crop rotation systems, presents a promising avenue for mitigating phosphorus (P) levels in drainage water by optimizing nutrient absorption across varying flooding conditions. This study aimed to assess the impacts of different flooding depths on rice growth and nutrient efficiency while exploring the interrelationships among these factors. Conducted over a two-year period, the field study involved planting a single rice variety (Diamond: 95 kg ha−1, long-grain, short-season) at four distinct flooding depths (5, 10, 15, and 20 cm) without fertilizer application. Results revealed minimal effects of flooding depths on root and shoot length or dry matter accumulation. Additionally, concentrations of total P and potassium (K) in both shoot and root tissues remained consistent across the different flooding depths. Despite the absence of P and K fertilizer inputs, no significant changes were observed in P use efficiency (PUE), K use efficiency (KUE), or water use efficiency (WUE). Cultivating rice under optimal flood depths of 5 cm within the Everglades Agricultural Area (EAA) demonstrated potential for conserving water and essential nutrients such as P and K. These findings highlight the feasibility of rice cultivation in fertile soils as a means to decrease nutrient (P and K) concentrations in drainage water, thereby promoting sustainable agricultural practices in the region.

Combination of Polymer-Coated Urea and Rapid-Release Urea Increases Grain Yield and Nitrogen Use Efficiency of Rice by Improving Root and Shoot Activities

The use of polymer-coated urea (PCU) can improve nitrogen use efficiency (NUE), compared to the application of rapid-release urea (RU). However, the effect of PCU-based nitrogen management on grain yield and the NUE of rice and its underlying mechanism remain unclear. A japonica rice cultivar Jinxiangyu 1 was grown in the field with four treatments including N omission (0N), split application of RU (Control), one-time application of 100% PCU (T1), and one-time application of 70% PCU + 30% RU (T2). Results showed that, compared to the control, the grain yield was significantly increased in the T2 treatment, while it was comparable in the T1 treatment. This was mainly due to increased total spikelets in the T2 treatment. Root oxidation activity (ROA) and root zeatin (Z) + zeatin riboside (ZR) content during booting were the distinct advantages of the T2 treatment, compared to either the control or T1 treatment, exhibiting significant or highly significant correlations with leaf photosynthesis. This process contributed significantly to total spikelets and total N uptake. Additionally, the T2 treatment absorbed more N than the control without reducing the internal N use efficiency (IEN), primarily due to its unchanged harvest index (HI) driven by comparable non-structural carbohydrate remobilization. In conclusion, combining PCU with RU can enhance the coordination of root and shoot traits during booting while maintaining a competitive HI at maturity, thereby significantly improving grain yield and achieving a balance in N uptake and utilization.

Diurnal and Seasonal Variations of Water Use Efficiency of Rice–Wheat Rotation Cropland in the Jianghuai River Basin of China

ABSTRACTRice–wheat rotation cropland is one of the most important agroecosystems in South China, the escalation of conflict between food demand augment and water supply shortage increased with climate change. Water use efficiency plays a more significant role in optimising water and carbon management. Thus, the diurnal and seasonal variations of water use efficiency were assessed by the 3‐year eddy covariance observations in the Shouxian National Observatory, a typical rice–wheat rotation station. The results revealed a ‘U’‐shaped diurnal pattern of water use efficiency for winter wheat (Triticum aestivum L.) and rice (Oryza sativa L.). Seasonal water use efficiency had two peaks with the highest in the winter wheat‐growing season. The average water use efficiency for the rice–wheat rotation cropland was 2.85 g C kg−1 H2O over the whole year with 2.62 and 3.11 g C kg−1 H2O for winter wheat and rice, respectively. However, gross primary productivity and evapotranspiration of rice were higher than those of winter wheat. Temperature, photosynthetically active radiation were the principal impact factors of water use efficiency in the rice‐growing season. Comparatively, soil water and vapour pressure deficit dominated the water use efficiency changes in the winter wheat‐growing season. Our analyses can help understand the water use requirements for carbon assimilation on rice–wheat rotation cropland on the field scale.

Assessing Yield, Quality and Nutrient Use Efficiency of Rice (Oryza sativa L.) with Agronomic Iron Bio-fortification

Assessing Yield, Quality and Nutrient Use Efficiency of Rice (Oryza sativa L.) with Agronomic Iron Bio-fortification

Nano fertilizers and its effect on nutrient use efficiency in rice

Nano fertilizers and its effect on nutrient use efficiency in rice

Energy Use Efficiency of late Sown Short Duration Rice Varieties Under Different Nitrogen Management Practices

One of the major causes of low nitrogen use efficiency in rice is the application of fertilizer nitrogen (N) more than crop requirement at times when it is not required by plant during late sown conditions. This experiment was conducted at Rajendranagar farm of ICAR-Indian Institute of Rice Research, Hyderabad during kharif2021. The experiment was laid out in split plot design with three replications. Main plots consisted of three short duration rice varieties DRR Dhan-44, MTU 1010, MTU 1156 and four nitrogen management practices (sub-plots) recommended dose of nitrogen (RDN) @ 120 kg N ha-1, Silicon coated urea (SCU) @ 90 kg ha-1, Leaf Colour Chart based N application (LCC)@105 kg N ha-1, Soil test crop response based N application (STCR) @ 114.5 kg N ha-1. Among the varieties highest energy input (13.22 GJ ha-1) was recorded in DRR Dhan-44 but energy output (172.6 GJ ha-1) and energy use efficiency (10.26 GJ ha-1) were recorded in MTU 1156. Among the N management practices highest energy input (13.94 GJ ha-1) was recorded in RDN@ 120 kg N ha-1 and energy use efficiency (10.38 GJ ha-1) was recorded with Leaf colour chart based N application@105 kg Nha-1

Effect of irrigation interval on water consumption, water use efficiency, growth and yield of rice in two area of Sulaymani governorate

The different of locations (which has different in soil and water quality) and irrigation interval has an important influence on water use efficiency and rice crop yield to determine the effects of different irrigation water management on yield and water use efficiency of rice (Oryza sativa L.) in two different locations soils and water quality, the two-field experiments were conducted on silty clay loam and silty clay soil, in earthen and western Suleimani province of Kurdistan-Iraq The experiment was a complete randomized design with a factorial arrangement of treatments with three replications. The main treatment was Irrigation interval (full irrigation (D1), one day (D2), two days (D3), and three-day irrigation (D4)) The depth irrigation were 939, 811, 726 and 681 mm, respectively for qaragol, while for chalax the depth irrigation were 980, 821, 749 and 722 mm respectively. The sub- treatment was, Qaragol (L1) and chalax (L2) locations respectively, the results showed that the effects of irrigation interval and locations and their interaction on rice grain yield and water use efficiency were significant at 5%. The highest grain yield (6263 Kg ha-1) belonged to the (L2) location and the lowest grain yield (5823.3 Kg ha-1) belonged to (L1) in Qaragol location. And the highest water use efficiency 8.547 in Qaragol location belongs to the (D4) and the lowest water use efficiency 6.387 increasing of water use efficiency (D1 vs. D4) caused a 29.5% improvement in water use efficiency. The irrigation schedule can be planned to save water without considerable reduction of crop yield

Effects of Deep Placement of Fertilizer on Growth, Productivity, and Fertilizer Use Efficiency of Rice in Cool Climatic Region

Effects of Deep Placement of Fertilizer on Growth, Productivity, and Fertilizer Use Efficiency of Rice in Cool Climatic Region

Rational Utilization of Sediment Resources Improves Rice Yield and Nitrogen Use Efficiency under Salt Stress

Soil salinization negatively affects rice growth and yield; however, how different sludge sources regulate rice growth and yield under salt stress was rarely investigated. This study evaluated the performance of two salt-tolerant rice cultivars, Chaoyou 1000 and Longliangyou 506, grown in two sediment sources, pond sediment (PS) and river sludge (RS), under salt stress (56 ds m−1 brine irrigation) with conventional soil (CS) used as the control. The results showed that the rice yield under the PS and RS treatments was enhanced by 51.0% and 43.6% as compared with CS, respectively, owing to an improvement in spikelet per panicle, 1000-grain weight, dry matter accumulation, and the chlorophyll content in both rice cultivars. Compared with CS, the total nitrogen accumulation, nitrogen grain production efficiency, nitrogen harvest index, and nitrogen partial productivity under the PS and RS treatments were increased by 18.9–28.9%, 17.0–20.6%, 7.2–16.6%, and 43.8–50.9%, respectively. Moreover, rice grown in PS and RS showed higher activities of nitrogen metabolism-related enzymes (nitrate reductase, glutamine synthetase, and glutamate synthetase) at the heading stage and higher K+ and K+/Na+ contents in the leaves. Overall, a balanced utilization of sediment resources (especially pond sediment) can effectively alleviate salt stress and improve the yield and nitrogen use efficiency in rice.

Promising physiological traits associated with nitrogen use efficiency in rice under reduced N application.

Higher grain yield in high-yielding rice varieties is mostly driven by nitrogen (N) fertilizer applied in abundant amounts leading to increased production cost and environmental pollution. This has fueled the studies on nitrogen use efficiency (NUE) to decrease the N fertilizer application in rice to the possible extent. NUE is a complex physiological trait controlled by multiple genes, but yet to be completely deciphered in rice. With an objective of identifying the promising physiological traits associated with NUE in rice, the performance of 14 rice genotypes was assessed at N0, N50, N100, and N150 for four (two wet and two dry) seasons using agro-morphological, grain yield, flag leaf traits, photosynthetic pigment content, flag leaf gas exchange traits, and chlorophyll fluorescence traits. Furthermore, the data were used to derive various NUE indices to identify the most appropriate indices useful to screen rice genotypes at N50. Results indicate that with the increase in N application, cumulative grain yield increased significantly up to N100 (5.02t ha-1); however, the increment in grain yield was marginal at N150 (5.09t ha-1). The mean reduction of grain yield was only 26.66% at N50 ranging from 15.0% to 34.2%. The significant finding of the study is the identification of flag leaf chlorophyll fluorescence traits (Fv/Fm, ΦPSII, ETR, and qP) and Ci associated with grain yield under N50, which can be used to screen N use efficient genotypes in rice under reduced N application. Out of nine NUE indices assessed, NUpE, NUtE, and NUEyield were able to delineate the high-yielding genotypes at N50 and were useful to screen rice under reduced N conditions. Birupa emerged as one of the high yielders under N50, even though it is a moderate yielder at N100 and infers the possibility of cultivating some of the released rice varieties under reduced N inputs. The study indicates the possibility of the existence of promising genetic variability for grain yield under reduced N, the potential of flag leaf chlorophyll fluorescence, and gas exchange traits as physiological markers and best suitable NUE indices to be deployed in rice breeding programs.

Productivity and nitrogen use efficiency of rice under conventional and organic nutrition

The current study demonstrates the influence of conventional and organic nutrient management practices on nitrogen use efficiency, growth, yield, and physiological and biochemical parameters in four rice varieties, namely, Jaiva, Ezhome 2, Jyothi and Uma. Growth parameters, grain yield per hill, and physiological and biochemical parameters were higher under conventional management for all rice varieties. Although the nitrogen use efficiency of each variety varied significantly with nutrient management practices, the variation was least in Jaiva (23.8%), which is the organic rice variety released by Kerala Agricultural University. The rice varieties Jaiva and Ezhome 2 showed consistency in the grain weight per panicle under both conventional (Jaiva- 4.57 g, Ezhome 2- 5.86 g) and organic (Jaiva, 4.24 g, Ezhome 2, 4.54 g) management. The soil nitrogen content at the tillering stage (0.66**) showed a significantly higher positive correlation with nitrogen use efficiency under organic management. The results of the study provide a better understanding of factors that can lead to a sustained yield in organic rice production in terms of nitrogen use efficiency.

Effect of Nitrogen Fertilizers Applied through Nano Clay Polymer Composites on Nitrogen Use Efficiency of Rice

Nitrogen (N) is an essential nutrient for crop growth. However, excessive nitrogen fertilizer application leads to environmental losses. In this study, an attempt was made to reduce the nitrogen losses by loading of urea and urea ammonium nitrate (UAN) into Nano clay polymer composites (NCPCs) to act as slow release N fertilizers. To achieve the objectives of the present study, five N fertilizer treatments (T1-control, T2- N applied through urea, T3- N applied through UAN, T4- N applied through NCPC loaded with urea and T5- N applied through NCPC loaded with UAN) were assessed using three rice genotypes namely IR-64, Nagina 22 and MTU 1010. Results of the greenhouse study indicated that the UAN loaded NCPC treatment was more effective in terms of increasing the grain yield, nitrogen uptake, agronomic use efficiency and apparent nitrogen recovery by 36.9%, 51.0%, 64.2%, and 92.0% over urea, respectively. Amongst the genotypes, MTU 1010 was recorded with highest gran yield followed by IR-64 and Nagina-22.

Exploration of chlorophyll fluorescence characteristics gene regulatory in rice (Oryza sativa L.): a genome-wide association study.

Chlorophyll content and fluorescence parameters are crucial indicators to evaluate the light use efficiency in rice; however, the correlations among these parameters and the underlying genetic mechanisms remain poorly understood. Here, to clarify these issues, we conducted a genome-wide association study (GWAS) on 225 rice accessions. In the phenotypic and Mendelian randomization (MR) analysis, a weak negative correlation was observed between the chlorophyll content and actual quantum yield of photosystem II (). The phenotypic diversity observed in SPAD, , , and among accessions was affected by genetic background. Furthermore, the GWAS identified 78 SNPs and 17 candidate genes significantly associated with SPAD, , , , and . Combining GWAS on 225 rice accessions with transcriptome analysis of two varieties exhibiting distinct fluorescence characteristics revealed two potential candidate genes (Os03g0583000 from & traits and Os06g0587200 from trait), which are respectively associated with peroxisomes, and protein kinase catalytic domains might involve in regulating the chlorophyll content and chlorophyll fluorescence. This study provides novel insights into the correlation among chlorophyll content and fluorescence parameters and the genetic mechanisms in rice, and offers valuable information for the breeding of rice with enhanced photosynthetic efficiency.

CRISPR/Cas9-mediated elimination of OsHHO3, a transcriptional repressor of three AMMONIUM TRANSPORTER1 genes, improves nitrogen use efficiency in rice.

CRISPR/Cas9-mediated elimination of OsHHO3, a transcriptional repressor of three AMMONIUM TRANSPORTER1 genes, improves nitrogen use efficiency in rice.

A meta-QTL analysis highlights genomic hotspots associated with phosphorus use efficiency in rice (Oryza sativa L.).

Phosphorus use efficiency (PUE) is a complex trait, governed by many minor quantitative trait loci (QTLs) with small effects. Advances in molecular marker technology have led to the identification of QTLs underlying PUE. However, their practical use in breeding programs remains challenging due to the unstable effects in different genetic backgrounds and environments, interaction with soil status, and linkage drag. Here, we compiled PUE QTL information from 16 independent studies. A total of 192 QTLs were subjected to meta-QTL (MQTL) analysis and were projected into a high-density SNP consensus map. A total of 60 MQTLs, with significantly reduced number of initial QTLs and confidence intervals (CI), were identified across the rice genome. Candidate gene (CG) mining was carried out for the 38 MQTLs supported by multiple QTLs from at least two independent studies. Genes related to amino and organic acid transport and auxin response were found to be abundant in the MQTLs linked to PUE. CGs were cross validated using a root transcriptome database (RiceXPro) and haplotype analysis. This led to the identification of the eight CGs (OsARF8, OsSPX-MFS3, OsRING141, OsMIOX, HsfC2b, OsFER2, OsWRKY64, and OsYUCCA11) modulating PUE. Potential donors for superior PUE CG haplotypes were identified through haplotype analysis. The distribution of superior haplotypes varied among subspecies being mostly found in indica but were largely scarce in japonica. Our study offers an insight on the complex genetic networks that modulate PUE in rice. The MQTLs, CGs, and superior CG haplotypes identified in our study are useful in the combination of beneficial alleles for PUE in rice.