Rice Biomass Yield Research Articles

Effect of Irrigation Management and Transplanting Date on the Rice Production and Water Productivity

ABSTRACT Water supply via irrigation and other water sources during the rice-growing season is vital for obtaining reasonable yield. The present study was carried out to investigate the dual-interacted effects of different irrigation intervals and transplanting dates on the yield, yield components, and water productivity of rice (Hashemi cultivar). The study was conducted in a three replicated randomized complete block design (RCBD) with the split-plot arrangement in two growing seasons (spring and summer) of 2016 and 2017 at Rice Research Institute of Iran, Rasht. The main factor was irrigation at four levels (full flooding, 5-, 10-, and 15-day irrigation intervals), and the second factor was three transplanting dates (April 21st, May 11th, and May 31st). The productivity of irrigation water (WPI) and irrigation water + precipitation (WPI+R) was reported in terms of grain yield and biomass. The highest paddy yield was observed in flooding treatment (4271 kg per hectare) and the irrigation intervals of 5, 10, and 15 days with 3844, 3196, and 3264 kg/ha were in the next rank, respectively. According to the biomass yield, 15-day irrigation interval and flooding irrigation had the highest and lowest water irrigation productivity, respectively. In the study of different transplanting dates, the highest paddy yield (3795 and 3820 kg/ha, respectively) was observed on the May 11th, and May 31st transplanting dates, and the highest water productivity based on paddy and biomass yield was obtained in the April 21st transplanting date. Regarding grain and biomass yield of rice, water productivity, and water use, the five-day irrigation treatment resulted in the best crop grain and biomass yield on April 21st transplanting date.

Wheat Straw Burial Enhances the Root Physiology, Productivity, and Water Utilization Efficiency of Rice under Alternative Wetting and Drying Irrigation

This study evaluated whether the straw burial and alternative wetting and drying (AWD) irrigation could improve the root activity, yield, and water utilization efficiency (WUE) of rice. Accordingly, we conducted a field experiment with three straw burial levels, i.e., with no straw burial (NSB), low straw burial 300 kg.ha−1 (LSB), and dense straw burial 800 kg.ha−1 (DSB), and three irrigation regimes, i.e., alternate wetting/moderate drying (AWMD), alternate wetting/severe drying (AWSD), and alternate wetting/critical drying (AWCD). Results showed that straw burial improved the root activity, rice yield, and WUE under AWD regimes. The combination AWMD×DSB resulted in the greatest values of total dry mass (1764.7 g/m2) and water use (853.1 mm). Conversely, the treatment AWCD × NSB led to the lowest values of total biomass (583.3 g/m2) and water use (321.8 mm). Root dry weight density (1.11 g cm−3) and root active absorption area (31.6 m2 plant−1) were higher in the treatment AWMD × DSB than root dry weight density (0.41 g cm−3) and root active absorption area (21.2 m2 plant−1) were in the treatment AWCD×NSB. The former combined treatment increased root oxidation ability (55.5 mg g−1 FWh−1), the root surface phosphatase activity (1.67 mg g−1 FWh−1) and nitrate reductase activity of root (14.4 μg g−1 h−1) while the latter considerably reduced the values of root oxidation ability (21.4 mg g−1 FWh−1), the root surface phosphatase activity (0.87 mg g−1 FWh−1) and nitrate reductase activity of root (5.8 μg g−1 h−1). The following conclusions can be drawn with regard to water use and biomass yield. (i) The reduction in water consumption was greater than the reduction in yield in the case of AWSD. (ii) The decline in water consumption was less than the decline in biomass yield in the case of AWCD. (iii) The increase in in water consumption was greater than the increase in biomass yield in the case of AWMD. Therefore, the indicators of WUE were recorded in the following order: AWSD > AWMD > AWCD. This study recommends AWD irrigation to improve the root growth traits that contribute to the greater biomass yield of rice. It also suggests that farmers should implement AWD irrigation after leaving wheat straw residues in the field, and followed by deep tillage, to mitigate the negative effect of drought stress caused by AWD irrigation, preserving plant growth without large biomass losses, and thus, addressing the constrains of straw residues and sustaining rice production under limited freshwater resources.

Peanut shell biochar’s effect on soil physicochemical properties and salt concentration in highly saline-sodic paddy fields in northeast China

Soil salinization is a major ecological threat to crop growth and production. Biochar addition can alleviate the negative impacts of saline-sodic stress in crops. Here, a two-year field experiment was conducted in a highly saline-sodic paddy field to evaluate the response of soil physico-chemical properties, ionic concentration, and rice yield to biochar applications. The soil was amended with peanut shell biochar as follows: zero biochar (B0), 33.75 t ha−1 (B1), 67.5 t ha−1 (B2), and 101.25 t ha−1 (B3). Biochar significantly reduced soil bulk density (BD), while it markedly increased total porosity (TP) and saturated hydraulic conductivity (Ks). Furthermore, biochar markedly decreased the Na+ concentration, Na+/K+ ratio, Na+/Ca2+ ratio, HCO3-, and CO32- while it increased the concentrations of K+, Ca2+, and Mg2+. Biochar significantly decreased the electrical conductivity of soil saturation extract (ECe). The exchangeable sodium percentage (ESP) of B1, B2, and B3 were 53.6%, 62.3%, and 71.0% lower, respectively, than that of B0, and the corresponding decrease in sodium adsorption ratio (SARe) was 51.2%, 58.1%, and 60.5%. Biochar had no effect on the soil pH but significantly increased the soil cation exchange capacity (CEC). The rice biomass yield, grain yield, and harvest index significantly increased after biochar application.

Different soil potassium fractions and their contribution towards its uptake under long-term rice-rice cropping system in an Inceptisol of subtropical eastern India

A pot culture experiment was conducted by taking soils from a long term fertilizer experimental field to evaluate the contribution of different K fractions towards rice biomass yield and potassium uptake in different long term fertilizer management practices. Twelve different soils were taken for pot culture and graded dose of potassium @ 0, 20, 40, 60, 80 and 100 kg K2O ha-1 was applied. Rice variety Lalat was grown as test crop. The forms of potassium were determined in the surface soil of 0-15 cm after maturity of crop. The result shows that water soluble form of K is the major contributor to biomass yield in soils taken from100% PK, 100% NPKZn, 100% NPKZnB,100% NPKZnS,100% NPK lime and control treated plots of the main field where as exchangeable K is dominant form of K in 100% NPK and 150% NPK. Ammonium acetate K contributes to yield in NPKFYM lime treatment. The nitric acid extractable K is a major contributor to yield in 100% NPKFYM,100% N or100% NP treatment. The water soluble form of K is the major source towards uptake in 150% NPK, NPKFYM lime ,100% NPKZnB, or control. Ammonium acetate K becomes the main source by applying 100% PK,100% NPK,100% NPKZn,100% NPKZnSor 100% NPKlime whereas exchangeable K becomes major contributor by100%N,or 100% NP application and 1 N HNO3 extractable K is the main source of K uptake in NPKFYM treatment. Therefore due importance of different form of potassium should be given in soil test value for better fertilizer management.

Effect of Silicon Application on Growth and Biomass Yield of Rice Under Salinity Stress

Effect of Silicon Application on Growth and Biomass Yield of Rice Under Salinity Stress

Biomass yield of rice (Oryza sativa) cultivars as affected by applied silicate in an Inceptisol

West Bengal is the largest rice (Oryza sativa L) producing state of India. In spite of leading the world in rice production, India lags behind in terms of rice productivity. In view of limited information, a pot experiment was conducted at ICAR-IARI, New Delhi during kharif, 2018-19 to evaluate the response of important rice cultivars to applied silicate. The experiment was conducted with four rice cultivars (one indigenous aromatic and rest three HYVs) and three doses of sodium metasilicate (0, 250 and 500 mg/kg) using an alluvial Inceptisol collected from West Bengal. Results indicated that the grain and straw yield was increased up to 40.7 and 18.1%, respectively, due to application of silicate. Rice cultivars, on the basis of grain yield, can be arranged in the order: Khitish (20.8 g/ pot)> Satabdi (17.6 g/pot) > IR-36 (15.4 g/pot) >Badshabhog (3.72 g/pot). The highest and the lowest straw yield was recorded with Badshabhog (70.1 g/pot) and IR-36 (14.6 g/pot), respectively. Rice cultivars showed differential responses in terms of yield to applied silicate. It can be concluded that application of sodium metasilicate can be one of the effective options for enhancing rice yield in the alluvial Inceptisol of West Bengal.

Biochar-based fertilizer: Supercharging root membrane potential and biomass yield of rice

Biochar-based compound fertilizers (BCF) and amendments have proven to enhance crop yields and modify soil properties (pH, nutrients, organic matter, structure etc.) and are now in commercial production in China. While there is a good understanding of the changes in soil properties following biochar addition, the interactions within the rhizosphere remain largely unstudied, with benefits to yield observed beyond the changes in soil properties alone. We investigated the rhizosphere interactions following the addition of an activated wheat straw BCF at an application rates of 0.25% (g·g−1 soil), which could potentially explain the increase of plant biomass (by 67%), herbage N (by 40%) and P (by 46%) uptake in the rice plants grown in the BCF-treated soil, compared to the rice plants grown in the soil with conventional fertilizer alone. Examination of the roots revealed that micron and submicron-sized biochar were embedded in the plaque layer. BCF increased soil Eh by 85 mV and increased the potential difference between the rhizosphere soil and the root membrane by 65 mV. This increased potential difference lowered the free energy required for root nutrient accumulation, potentially explaining greater plant nutrient content and biomass. We also demonstrate an increased abundance of plant-growth promoting bacteria and fungi in the rhizosphere. We suggest that the redox properties of the biochar cause major changes in electron status of rhizosphere soils that drive the observed agronomic benefits.

Impact of Microwave Soil Heating on the Yield and Nutritive Value of Rice Crop

Microwave (MW) soil heating has been shown to deplete the soil weed seedbank and increase crop productivity. However, the impact of MW soil heating on the nutritive value of crops is unknown. In this study, two field trials were conducted to evaluate the effect of pre-sowing MW soil treatment with a duration of 60 s and an untreated control, which were assigned in a randomized complete block design with five replicates at two locations, on the yield and nitrogen (N) accumulation pattern of rice crops. At Jerilderie site, soil heating at up to 70–75 °C significantly (p ˂ 0.09) increased the rice biomass yield by 43.03% compared with rice biomass yield in untreated soils, while at Dookie site no significant increase in biomass yield was detected. Dry matter digestibility (DMD), ash, and N% did not change, whereas the N accumulation in dry biomass was significantly (p ˂ 0.09) higher at both sites (8.2% at Dookie and 43.4% at Jerilderie) and N use efficiency (10–40%) increased in response to MW soil treatment. The current study suggests that MW soil treatment can potentially enhance the crop productivity and N accumulation in dry biomass under field conditions. Future research is needed to understand the impact of MW soil heating on the productivity and nutritive value of different fodder crops under field conditions.

Evaluation of Rice Straw Yield, Fibre Composition and Collection Under Mediterranean Conditions

Abstract Rice straw remains almost unutilised in the majority of cases and is usually burned. Data on rice residue production under European conditions are extremely limited. A detailed assessment of rice biomass yield, partitioning and straw collection was carried out in Spain. Eleven commercial rice varieties were evaluated in 2015, and two baling trials were performed in 2014 and 2015. The average straw yield was 9.7 t·ha−1. Straw yield, biomass partitioning indices and fibre composition varied significantly according to rice variety. Straw to grain ratio and harvest index were 1.00 and 0.50 on average for rough grain, and 1.25 and 0.41 for husked grain. Biomass partitioning indices significantly correlated with grain yield. Mean content of cellulose, hemicellulose, lignin and ash of rice straw was 32.5%, 19.8%, 6.5% and 13.7%, respectively. Straw amount of less than 3.0 t·ha−1 can be collected during the baling trials. Rice straw could represent an eco-friendly source of lignocellulosic biomass in Europe, however, in order to achieve this, baling machine improvements and special crop management should be carried out.

Impact of no-till and mulching on soil carbon sequestration under rice (Oryza sativa L.)-rapeseed (Brassica campestris L. var. rapeseed) cropping system in hilly agro-ecosystem of the Eastern Himalayas, India

Decline in soil organic carbon (SOC) and low biomass production in sloping uplands are of growing concern for sustainable agriculture worldwide. This concern is in general in the Eastern Himalayan regions (EHR) of India in particular. A field experiment was conducted with the objectives to generate additional biomass and sequester more C in coarse-textured sloping lands. This experiment is done for four consecutive years in the EHR, India. The rice (Oryza sativa L.)–rapeseed (Brassica campestris L. var. rapeseed) cropping system was practiced during the first two years (2012-13 to 2013-14) and rice–rapeseed–cowpea (Vigna unguiculata L.) system during the two following years (2014-15 to 2015-16) of the study under different tillage and mulch systems. The tillage system included: 1) CT-RI: conventional tillage (CT) with 100% residue incorporation (RI) and 2) NT-RR: no-till (NT) with 100% residue retention (RR). The mulches included 1) rice straw mulch (SM), 2) Gliricidia sp. mulch (GM), 3) brown manuring mulch (BM)–cowpea grown as intercrop with rice up to 40 days after sowing (DAS), killed with 2,4-D and 4) no mulch (NM). The cowpea, as a cover crop was introduced during 2014 and 2015 as pre-rainy season crop before the sowing of rice to generate additional biomass in the system. The four year total above ground biomass yield of rice and rapeseed didn’t vary significantly between CT-RI (31.93 and 17.40 Mg ha−1) and NT-RR (31.86 and 17.46 Mg ha−1), respectively. However, the total above ground biomass yield of cowpea was more under NT-RR (10.75 Mg ha−1) when compared to that under CT-RI (9.79 Mg ha−1). The amount of total biomass (above + below ground) and C added into the soil was more under NT-RR than that under the CT-RI. After 4 cropping cycles, the NT-RR had higher SOC concentration, pool (29.9 vs. 29.1 Mg ha−1), sequestration rate (450 vs. 265 kg ha-1 yr−1) and C retention efficiency (7.7 vs. 4.6%) than those under the CT-RI at 0–30 cm depth. The mulched plots produced more crop biomass (both above and below ground), recycled more C in soils with a trend of relatively more SOC pool (29.7–29.8 vs. 29.0 Mg ha−1), sequestration rate (391–428 vs. 221 kg ha-1 yr−1) and C retention efficiency (6.64–6.94% vs. 4.66%) than those of NM treatment. These results were seen despite difference among the mulch treatments (SM, GM and BM) which were statistically non-significant after 4 cropping cycles. Inclusion of cowpea as cover crop during pre-rainy season in the system doubled the rate of C sequestration (478 kg C ha-1 yr−1). Therefore, the data supports the recommendation of cultivation of the rice–rapeseed system under NT-RR along with cowpea intercropping up to 40 DAS (BM) in rice. Besides this, the inclusion of pre-rainy season cowpea before rice could generate additional biomass and enhance SOC sequestration on upland and sloping hills in the EHR of India and in similar conditions elsewhere.

A follow-up study for biomass yield QTLs in rice.

The biomass yield (plant weight) of rice fluctuates from year to year. In a previous study, we demonstrated that six quantitative trait loci (QTLs) contribute to the variation in the plant weight of recombinant inbred lines (RILs) of high-yielding Japanese rice cultivars. However, it remains unclear whether the effects of those QTLs are stable over multiple years. Therefore, we evaluated the effect of the alleles on the plant weight of RILs over multiple years, including a change of fertilization level (i.e., in different environments). Even though the biomass yields of all RILs fluctuated among environments, RILs that were selected on the basis of the genotypes of the detected QTLs had a stable rank order of plant weight that corresponded to their genotypes. This multiple-environment experiment reveals the highly significant contribution of both genotypic and environmental variances to the observed variance in plant weight. A marginally significant QTL–environment interaction was detected at only one of the six QTLs, with a subtle contribution. These results support the idea that the biomass yield of rice can be improved through QTL-based allele selection.

The dynamics of nitrogen derived from a chemical nitrogen fertilizer with treated swine slurry in paddy soil-plant systems

A well-managed chemical nitrogen (N) fertilization practice combined with treated swine slurry (TSS) is necessary to improve sustainability and N use efficiency in rice farming. However, little is known about the fate of N derived from chemical N fertilizer with and without TSS in paddy soil-plant systems. The objectives of this study were (1) to estimate the contribution of applied N fertilizer to N turnover in rice paddy soil with different N fertilization practices that were manipulated by the quantity of treated swine slurry and chemical N fertilizer (i.e., HTSS+LAS, a high amount of TSS with a low amount of ammonium sulfate; LTSS+HAS, a low amount of TSS with a high amount of ammonium sulfate; AS, ammonium sulfate with phosphorus and potassium; C, the control) and (2) to compare the rice response to applied N derived from each N fertilization practice. Rice biomass yield, 15N recovery in both rice grain and stems, soil total N (TN), soil inorganic N, and soil 15N recovery were analyzed. Similar amounts of 15N uptake by rice in the TSS+AS plots were obtained, indicating that the effects of the different quantities of TSS on chemical fertilizer N recovery in rice during the experimental period were not significant. The soil 15N recoveries of HTSS+LAS, LTSS+HAS, and AS in each soil layer were not significantly different. For the HTSS+LAS, LTSS+HAS and AS applications, total 15N recoveries were 42%, 43% and 54%, respectively. Because the effects of reducing the use of chemical N fertilizer were attributed to enhancing soil quality and cost-effectiveness, HTSS+LAS could be an appropriate N fertilization practice for improving the long-term sustainability of paddy soil-plant systems. However, N losses, especially through the coupled nitrification-denitrification process, can diminish the benefits that HTSS+LAS offers.

Growth, yield components and grain yield response of rice to temperature and nitrogen levels

An experiment was carried out during the kharif season of year 2013 inside Temperature Gradient Tunnel (TGT) of Centre for Environment Science and Climate Resilient Agriculture (CESCRA), at IARI farm to study impact of elevated temperature on the growth and yield responses of rice crop under four N levels. Results showed that grain and biomass yield of rice had decreased significantly with rise in temperature inside the TGT. With recommended N dose, yield reduction of rice was 37 per cent with rise in temperature to 3.9ºC over ambient air condition but application of 125 per cent N can prevent the yield loss by 6per cent as compared to 100 per cent recommended N treatment. Yield parameters Spikelet sterility of rice did increase with increase in temperature.

Improvement of Rice Biomass Yield through QTL-Based Selection.

Biomass yield of rice (Oryza sativa L.) is an important breeding target, yet it is not easy to improve because the trait is complex and phenotyping is laborious. Using progeny derived from a cross between two high-yielding Japanese cultivars, we evaluated whether quantitative trait locus (QTL)-based selection can improve biomass yield. As a measure of biomass yield, we used plant weight (aboveground parts only), which included grain weight and stem and leaf weight. We measured these and related traits in recombinant inbred lines. Phenotypic values for these traits showed a continuous distribution with transgressive segregation, suggesting that selection can affect plant weight in the progeny. Four significant QTLs were mapped for plant weight, three for grain weight, and five for stem and leaf weight (at α = 0.05); some of them overlapped. Multiple regression analysis showed that about 43% of the phenotypic variance of plant weight was significantly explained (P < 0.0001) by six of the QTLs. From F2 plants derived from the same parental cross as the recombinant inbred lines, we divergently selected lines that carried alleles with positive or negative additive effects at these QTLs, and performed successive selfing. In the resulting F6 lines and parents, plant weight significantly differed among the genotypes (at α = 0.05). These results demonstrate that QTL-based selection is effective in improving rice biomass yield.

Effect of Fertilization on the Dynamics and Activity of Iron-Reducing Bacterial Populations in a West African Rice Paddy Soil Planted with Two Rice Varieties: Case Study of Kou Valley in Burkina Faso

Iron toxicity is a major stress to rice caused by a high concentration of reduced iron, in the soil in many lowlands worldwide. To reduce iron toxicity in the West African lowlands, an investigation was performed at the site of the University of Ouagadougou, in pots containing an iron toxic soil from the Kou Valley (West of Burkina Faso). The experiment objective was to study the effect of mineral fertilizer on Iron Reducing Bacteria (IRB) dynamics and activity during rice cultivation, iron accumulation in rice plant and rice biomass yield under iron toxicity conditions. BOUAKE-189 and ROK-5 rice varieties, sensitive and tolerant to iron toxicity, respectively, were used for the experiment. The pots were amended with chemical fertilizers (NPK + Urea and NPK + Urea + Ca + Mg + Zn complex). Control pots without fertilization were prepared similarly. The kinetics of IRB and ferrous iron content in soil near rice roots were monitored throughout the cultural cycle using MPN and colorimetric methods, respectively. The total iron content was evaluated in rice plant using spectrometric method. Data obtained were analyzed in relation to fertilization mode, rice growth stage and rice yield using the student’s t-test and XLSTAT 2014 statistical software. The experiment revealed that NPK + Urea and NPK + Urea + Ca + Mg + Zn fertilization, decreased significantly (p

Impact of elevated temperature on iron and zinc uptake in rice crop

Climate change associated with rise in temperature has adverse impact on global food production. Rice crop is also affected by this rise in atmospheric temperature. An experiment was conducted during the kharif season of year 2013 inside Temperature Gradient Tunnel (TGT) in IARI farm, to study impact of elevated temperature on uptake of iron (Fe) and zinc (Zn) in rice crop. There were 5 different temperature treatments inside the TGT. Two nitrogen (N) doses were applied in all 5 temperature treatments. Results showed that high temperature stress significantly reduced both grain and biomass yields of rice crop. Grain and biomass yield of rice reduced by 26.6% and 23.5% respectively in treatment with 100% recommended dose of nitrogen. Uptake of Fe and Zn decreased significantly with rise in temperature. Uptake of Fe and Zn in rice grains reduced by 41.5% and 27.3% respectively with rise in temperature by 3.9°C. Reduced yield at higher temperature has resulted in lower micronutrient uptake of the crop. Application of N dose, reduced the harmful effect of temperature rise to certain extent.

Organic Phosphorus Fractions in Organically Amended Paddy Soils in Continuously and Intermittently Flooded Conditions

Soil organic phosphorus (SOP) can greatly contribute to plant-available P and P nutrition. The study was conducted to determine the effects of organic amendments on organic P fractions and microbiological activities in paddy soils. Samples were collected at the Changshu Agro-ecological Experiment Station in Tahu Lake Basin, China, from an experiment that has been performed from 1999 to 2004, on a paddy soil (Gleysols). Treatments consisted of swine manure (SM), wheat straw (WS), swine manure plus wheat straw (SM + WS), and a control (chemical fertilization alone). Organic amendments markedly increased soil total organic phosphorus (TOP) and total organic carbon (TOC), especially in continuously flooded conditions. Based on the fractionation of SOP, organic amendments significantly increased soil labile organic phosphorus (LOP), moderately labile organic phosphorus (MLOP), and moderately stable organic phosphorus (MSOP) compared with the control. For SM and SM + WS treatments, LOP in continuously flooded soils decreased by 30.1 and 36.4%, respectively, compared to intermittently flooded soils. In organically amended soils, continuous flooding showed significantly lower microbial biomass phosphorus (MBP) and alkaline phosphatase activities (APA) than intermittent flooding. In intermittently flooded conditions, incorporating organic amendments into soil resulted in greater P uptake and biomass yield of rice than the control. In the intermittently flooded soils, APA (P < 0.05) and MBP (P < 0.01) were significantly and positively related to TOP, LOP, MLOP, and MSOP, whereas in continuously flooded soils, there was a significant (P < 0.05) negative relationship between MBP, TOP, and MSOP. Based on soil organic P fractions and soil enzymatic and microbiological activities, continuous flooding applied to paddy soils should be avoided, especially when swine manure is incorporated into paddy soil.

Mapping QTL for Biomass Yield and Its Components in Rice ( Oryza sativa L.)

Addicive effects, additive by additive epistatic effects, and their environmental interactions of QTLs are important genetic components of quantitative traits. Genetic architecture underlying rice biomass yield and its two component traits (straw yield and grain yield) were analyzed for a population of 125 DH lines from an inter-subspecific cross of IR64/Azucena. The mixed-model based composite interval mapping approach (MCIM) was used to detect QTLs, There were 12 QTLs detected with additive main effects, 27 QTLs involved in digenic interaction with aa and/or aae effects, and 18 QTLs affected by environments with ae and/or aae effects. It was revealed that epistatic effects and QE interaction effects existed on biomass yield and its component traits in rice. In addition, the genetic basis of relationships among these traits were investigated. Four QTLs and one pair of epistatic QTLs were detected to be responsible for the positive correlation between biomass yield and straw yield. Three QTLs might be responsible for the negative correlation between straw yield and grain yield. This result could partially explain the genetic basis of correlation among the three traits, and provide useful information for genetic improvement of these traits by marker-assisted selection.