Rice phenology and growth simulation using CERES-Rice model under the agro-climate of upper Brahmaputra valley of Assam

Crop growth simulation models, properly validated against experimental data have the potential for facilitating strategic decision making in agriculture. Such validated models can also make use of the information generated for site specific experiments and trials to other sites and for different time durations. For proper calibration and evaluation of crop simulation models, there is a need for collection of a comprehensive minimum set of data on soil, weather and crop management in all agronomic experiments. Keeping this in view, data from seven field experiments conducted at Jorhat (26° 47' N, 94°12' E; 87 m amsl) during 1998-2005 for long duration rice cultivar Ranjit grown under rainfed conditions were collected. Genetic coefficients required for running the CERES-Rice v4.5 model were derived and the performance of the model under the climate of upper Brahmaputra valley was evaluated. These results indicate that the CERES Rice v4.5 model is capable of estimating growth stages and grain yield of rice cultivar Ranjit in the climatic conditions of upper Brahmaputra valley with reasonable accuracy. Hence, the model have the potential for its use as a tool in making various strategic and tactical decisions related to agricultural planning in the state.

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Validation of CERES-Rice v3.5 under the climate of Andhra Pradesh state, India

MAUSAM ◽

10.54302/mausam.v52i3.1725 ◽

2022 ◽

Vol 52 (3) ◽

pp. 551-560

Author(s):

S. A. SASEENDRAN ◽

D. RAJI REDDY ◽

L. S. RATHORE ◽

S. B. S. NARASIMHA RAO ◽

S. V. SINGH

Keyword(s):

Grain Yield ◽

Andhra Pradesh ◽

Field Experiments ◽

Simulation Models ◽

Climatic Conditions ◽

Strategic Decision ◽

Average Error ◽

Crop Varieties ◽

Agricultural Planning ◽

Tactical Decisions

Crop growth simulation models, properly validated against experimental data have the potential for tactical and strategic decision making in agriculture. Such validated models can also take the information generated through site specific experiments and trials to other sites and years. For proper calibration and evaluation of crop simulation models, there is a need for collection of a comprehensive minimum set of data on soil, weather and crop management in all agronomic experiments. Keeping this in view, field experiments were conducted at Rajendranagar (17°19' N, 78°23' E; 542.3 m amsl) during 1994-97 for three popular varieties of rice viz. Sambamasuri, Rajavadlu and Tellahamsa under irrigated conditions and data collected. Genetic coefficients required for running the CERES-Rice v3.5 model were calculated and the performance of the model under the climate of the area was evaluated. The results of the study show that the model simulations of date of flowering for Sambamasuri, Rajavadlu and Tellahamsa were within an average error of 6.2, 5.7 and 6.7 days respectively. Similar errors in predictions of physiological maturity dates were 7.6, 6.7 and 7.2 days. The error in grain yield predictions by the model averaged at 7.9%, 8.3%, and 5.7% respectively for the three crop varieties. These results indicate that the CERES Rice v3.5 model is capable of prediction of grain yield and phenological development of the crop in the climatic conditions of Andhra Pradesh with reasonable accuracy and hence, the model have the potential for its use as a tool in making various strategic and tactical decisions related to agricultural planning in the state.

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Simulating winter wheat shoot apex phenology

The Journal of Agricultural Science ◽

10.1017/s0021859600071483 ◽

1992 ◽

Vol 119 (1) ◽

pp. 1-12 ◽

Cited By ~ 45

Author(s):

G. S. McMaster ◽

W. W. Wilhelm ◽

J. A. Morgan

Keyword(s):

Winter Wheat ◽

Great Plains ◽

Shoot Apex ◽

Cultural Practices ◽

Seedling Emergence ◽

Simulation Models ◽

Climatic Conditions ◽

Growth Stages ◽

Developmental Sequence ◽

Wheat Shoot

SummarySimulation models are heuristic tools for integrating diverse processes and help to increase our understanding of complex processes and systems. Models that predict crop development can serve as decision-support tools in crop management. This paper describes a phenology simulation model for the winter wheat shoot apex and reports validation and sensitivity analysis results.The complete developmental sequence of the winter wheat shoot apex is quantitatively outlined and correlated with commonly recognised phenological growth stages. The phyllochron is used to measure the thermal time between most phenological growth stages, thereby increasing the flexibility over the growing degree-day (GDD) and photothermal approaches. Nineteen site-years covering a range of climatic conditions, cultural practices and cultivars across the Central Great Plains, USA, are used to validate the model.Validation results show that the predicted phyllochron (108 GDD) agrees well with the observed phyllochron (107 GDD) for ten cultivars. Mean seedling emergence is predicted to within 2 days in almost all of the 19 site-years. The ability of the model to predict growth stages accurately increased successively from jointing to heading to maturity. Maturity is generally predicted to within 5 days of the observed day.After validation, recalibration of the phyllochron estimates between growth stages are provided, and corrections for mesic and xeric conditions are suggested. Further validation of the entire developmental sequence of the shoot apex is recommended.

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Characterization of rice cultivar response to florpyrauxifen-benzyl

Weed Technology ◽

10.1017/wet.2020.80 ◽

2020 ◽

pp. 1-11

Author(s):

Hannah E. Wright ◽

Jason K. Norsworthy ◽

Trenton L. Roberts ◽

Robert Scott ◽

Jarrod Hardke ◽

...

Keyword(s):

Field Experiments ◽

Rice Cultivar ◽

Growth Chamber ◽

Yield Response ◽

Growth Stages ◽

Research Station ◽

Rice Cultivars ◽

Visible Injury ◽

Pine Tree ◽

Temperature Regimes

Abstract Many factors such as environment, herbicide rate, growth stage at application, and days between sequential applications can influence the response of a crop to herbicides. Florpyrauxifen-benzyl is a new broad-spectrum, POST herbicide that was commercialized for use in U.S. rice production in 2018. Field experiments were conducted in 2018 at the Pine Tree Research Station (PTRS) near Colt, AR, and the Rice Research and Extension Center (RREC), near Stuttgart, AR, to evaluate crop injury and yield response of three rice cultivars to sequential applications of florpyrauxifen-benzyl. Greenhouse and growth chamber experiments were conducted at the Altheimer Laboratory in Fayetteville, AR, to evaluate cultivar responses when florpyrauxifen-benzyl was applied at 30 or 60 g ae ha−1 to rice exposed to different temperature regimes or at various growth stages. Three rice cultivars were used in all experiments: long-grain variety ‘CL111’, medium-grain variety ‘CL272’, and long-grain hybrid cultivar ‘CLXL745’. CL111 exhibited sufficient tolerance to florpyrauxifen-benzyl with only 10% visible injury and no effect on yield. CL272 showed 15% injury 3 wk after the second application in the field experiment when applications were made 14 d apart. Additionally, 12% injury was observed in greenhouse studies when florpyrauxifen-benzyl was applied at 30 g ae ha−1, averaged over various growth stages at application. Florpyrauxifen-benzyl did not reduce the yield of CL272 in field experiments, indicating that CL272 can recover from florpyrauxifen-benzyl injury. As much as 64% injury was observed for CLXL745 at 3 wk after application (WAA) when sequential herbicide applications were made 4 d apart. High levels of injury occurred in the growth chamber and greenhouse studies for this cultivar as well. Sequential applications of florpyrauxifen-benzyl reduced yields of CLXL745 in nearly all treatments. Data from these experiments suggest that CL272 and CLXL745 are sensitive to sequential applications of florpyrauxifen-benzyl. Growers must follow the prescribed guidelines for using florpyrauxifen-benzyl in these cultivars and others like it.

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Effect of Flood Timing on Red Rice (Oryzaspp.) Control with Imazethapyr Applied at Different Dry-Seeded Rice Growth Stages

Weed Technology ◽

10.1614/wt-04-181 ◽

2005 ◽

Vol 19 (2) ◽

pp. 476-480 ◽

Cited By ~ 20

Author(s):

Luis A. Avila ◽

Scott A. Senseman ◽

Garry N. McCauley ◽

James M. Chandler ◽

John H. O'Barr

Keyword(s):

Grain Yield ◽

Field Experiments ◽

Rice Cultivar ◽

Growth Stages ◽

Rice Grain ◽

Red Rice ◽

Cultivated Rice ◽

Leaf Stage ◽

Rice Growth ◽

Herbicide Treatment

Field experiments were conducted in 2002 and 2003 in Beaumont, TX, to evaluate the effect of flood timing on red rice control with imazethapyr applied at different cultivated rice growth stages. Treatments included flood establishment at 1, 7, 14, and 21 d after postemergence (POST) herbicide treatment (DAT). Imazethapyr was applied preemergence at 70 g ai/ha followed by 70 g/ ha POST when imidazolinone-tolerant rice cultivar ‘CL-161’ had three- to four-leaf stage (EPOST) or five-leaf stage (LPOST). Flood needed to be established within 14 DAT to achieve at least 95% red rice control when imazethapyr was applied EPOST. However, flood needed to be established within 7 DAT to provide at least 95% red rice control when imazethapyr was applied LPOST. Delaying the flood up to 21 DAT reduced rice grain yield for both application timings.

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Effect of increasing doses of nitrogen and sulphur on chemical composition of plants, yields and seed quality in winter rape

Plant Soil and Environment ◽

10.17221/4197-pse ◽

2011 ◽

Vol 48 (No. 1) ◽

pp. 1-6

Author(s):

L. Hřivna ◽

R. Richter ◽

T. Lošák ◽

J. Hlušek

Keyword(s):

Field Experiments ◽

Seed Quality ◽

Synergetic Effect ◽

Climatic Conditions ◽

Individual Growth ◽

Growth Stages ◽

Winter Rape ◽

Seed Yields ◽

Positive Effect ◽

Number Of Branches

In 1999, the effect of increasing levels of nitrogen at the initial (13.9 mg.kg–1) and increased (40 mg.kg–1) level of watersoluble sulphur (Swat) was studied in winter rape (cv. Lirajet) grown in pots. A synergetic effect of nitrogen on concentrations of Ca and Mg was demonstrated in the growth stages DC 20–29 and 31–39. Levels of P and K were balanced. In variants with a low content of Swat in soil to 40 mg.kg–1 of soil S concentration increased. With the increasing dose of N the content of S decreased from 1.00% to 0.78% and from 0.68% to 0.38% in DC 20–29 and DC 31–39, respectively. An increased level of S in soil changed the ratio N/S. In variants with a natural (i.e. low) content of S in soil, this ratio widened with the increasing dose of N from 8.06 to 25.15 while in variants with an increased level of S in soil it ranged from 3.24 to 5.85 in the growth stage DC 20–29. Increasing doses of N widened the ratio N/P regardless to concentration of S in plants. In individual growth stages the ratio P/S was markedly narrowed by changing contents of S in soil. The highest yields were obtained in the variant with an optimum concentration of all elements in plants and S contents above 0.6% and/or about 0.4% in growth stages DC 20–29 and DC 31–39, respectively. The obtained yields demonstrated a highly significant effect of N and S on seed yields. At a low concentration of sulphur in plants the yield of seed increased only to the dose N3(i.e. 0.9 g N per pot); thereafter, it gradually decreased. An increased level of S in soil showed a positive effect on seed yields. Higher doses of N widened the ratio straw/seeds from 2.46 to 7.69; at higher levels of S in soil, an opposite trend was observed. In variants with a low content of S the number of branches and pods increased proportionally with increasing doses of N. On the other hand, increased levels of S reduced the number of branches and pods. At a low level of S in soil the total weight of seeds per pod decreased with the increased supply of N from 69.9 mg to 20.4 mg. At increased levels of S the weight of seeds per pod increased from 61.9 mg to 79.8 mg. Results of field experiments in four different localities corroborated a positive effect of S (in interaction with N) on its concentration in plants. The seed yield was significantly increased. In 2000, results from all localities were markedly influenced by climatic conditions; however average results of all experiments showed that S increased seed yields depending on the dose of N by 2.5 and 5.9%. An optimum nutrition of plants with all elements (including S) results in improved utilisation and increased yields.

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Comparative study of amaranth species (Amaranthus spp.) in the temperate continental climate of Russian Federation

Acta agriculturae Slovenica ◽

10.14720/aas.2020.115.1.1281 ◽

2020 ◽

Vol 115 (1) ◽

pp. 15

Author(s):

Oksana DMITRIEVA ◽

Semen IVANOV

Keyword(s):

Field Experiments ◽

Common Species ◽

Climatic Conditions ◽

Annual Rainfall ◽

Growth Stages ◽

Volga River ◽

Green Mass ◽

Amaranth Species ◽

Chuvash Republic ◽

Continental Climate

Field experiments were carried out in the Chuvash Republic, which is located in the center of the European part of Russia on the banks of the Volga River and has a moderately continental climate with warm summers, cold winters, well-defined transitional seasons and average annual rainfall of 500 mm. There are many cultural and wild species of amaranth in nature, differing in morphological and biological features. The objects of research were four common species of amaranth (Amaranthus spp.): A. cruentus L., A. caudatus L., A. hybridus L., A. spinosus L.. Particular attention in the experiment was paid to the morphological and biological characteristics of plants according to the growth stages during growing season and the formation of the yield of green mass and grain during 3 years of research. As a result of the experiment, the possibility of cultivating a heat-loving amaranth culture in the climatic conditions of the Chuvash Republic was proved and adaptive species for growing green mass (A.cruentus and A.caudatus) and for grain (A.cruentus) were identified.

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Comparative study of amaranth species (Amaranthus spp.) in the temperate continental climate of Russian Federation

Acta agriculturae Slovenica ◽

10.14720/aas.2020.115.1.2 ◽

2020 ◽

Vol 115 (1) ◽

pp. 15

Author(s):

Oksana DMITRIEVA ◽

Semen IVANOV

Keyword(s):

Field Experiments ◽

Common Species ◽

Climatic Conditions ◽

Annual Rainfall ◽

Growth Stages ◽

Volga River ◽

Green Mass ◽

Amaranth Species ◽

Chuvash Republic ◽

Continental Climate

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Effect of Temperature on Sowing Dates of Wheat under Arid and Semi-Arid Climatic Regions and Impact Quantification of Climate Change through Mechanistic Modeling with Evidence from Field

Atmosphere ◽

10.3390/atmos12070927 ◽

2021 ◽

Vol 12 (7) ◽

pp. 927

Author(s):

Jamshad Hussain ◽

Tasneem Khaliq ◽

Muhammad Habib ur Rahman ◽

Asmat Ullah ◽

Ishfaq Ahmed ◽

...

Keyword(s):

Climate Change ◽

Grain Yield ◽

Arid Region ◽

Field Experiments ◽

Climatic Conditions ◽

Seasonal Temperature ◽

Sowing Dates ◽

Rcp 8.5 ◽

Semi Arid Region ◽

Semi Arid

Rising temperature from climate change is the most threatening factor worldwide for crop production. Sustainable wheat production is a challenge due to climate change and variability, which is ultimately a serious threat to food security in Pakistan. A series of field experiments were conducted during seasons 2013–2014 and 2014–2015 in the semi-arid (Faisalabad) and arid (Layyah) regions of Punjab-Pakistan. Three spring wheat genotypes were evaluated under eleven sowing dates from 16 October to 16 March, with an interval of 14–16 days in the two regions. Data for the model calibration and evaluation were collected from field experiments following the standard procedures and protocols. The grain yield under future climate scenarios was simulated by using a well-calibrated CERES-wheat model included in DSSAT v4.7. Future (2051–2100) and baseline (1980–2015) climatic data were simulated using 29 global circulation models (GCMs) under representative concentration pathway (RCP) 8.5. These GCMs were distributed among five quadrants of climatic conditions (Hot/Wet, Hot/Dry, Cool/Dry, Cool/Wet, and Middle) by a stretched distribution approach based on temperature and rainfall change. A maximum of ten GCMs predicted the chances of Middle climatic conditions during the second half of the century (2051–2100). The average temperature during the wheat season in a semi-arid region and arid region would increase by 3.52 °C and 3.84 °C, respectively, under Middle climatic conditions using the RCP 8.5 scenario during the second half-century. The simulated grain yield was reduced by 23.5% in the semi-arid region and 35.45% in the arid region under Middle climatic conditions (scenario). Mean seasonal temperature (MST) of sowing dates ranged from 16 to 27.3 °C, while the mean temperature from the heading to maturity (MTHM) stage was varying between 12.9 to 30.4 °C. Coefficients of determination (R2) between wheat morphology parameters and temperature were highly significant, with a range of 0.84–0.96. Impacts of temperature on wheat sown on 15 March were found to be as severe as to exterminate the crop before heading. The spikes and spikelets were not formed under a mean seasonal temperature higher than 25.5 °C. In a nutshell, elevated temperature (3–4 °C) till the end-century can reduce grain yield by about 30% in semi-arid and arid regions of Pakistan. These findings are crucial for growers and especially for policymakers to decide on sustainable wheat production for food security in the region.

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Red Rice (Oryza sativa) Control in Drill-Seeded Rice (O. sativa)

Weed Science ◽

10.1017/s0043174500083120 ◽

1985 ◽

Vol 33 (5) ◽

pp. 703-707 ◽

Cited By ~ 8

Author(s):

Amadou Diarra ◽

Roy J. Smith ◽

Ronald E. Talbert

Keyword(s):

Oryza Sativa ◽

Grain Yield ◽

Field Experiments ◽

Growing Season ◽

Rice Cultivar ◽

Rice Grain ◽

Rice Seed ◽

Red Rice ◽

Culm Density ◽

High Yields

Field experiments were conducted to investigate methods of controlling red rice (Oryza sativaL. ♯ ORYSA) in drill-seeded rice (O. sativa). Treatments included the rice cultivar ‘Mars', coated with calcium peroxide (CaO2) at 40% (w/w) and a crop protectant, R-33865 (O,O-diethyl-O-phenyl phosphorothioate) at 0.5 and 1% (v/w). Molinate (S-ethyl hexahydro-1H-azepine-1-carbothioate) at 6.7 kg ai/ha was applied preplant incorporated (ppi). The land was flooded (2.5 to 5 cm deep) after seeding with rice (100 kg/ha, 2.5 cm deep), and the water was maintained throughout the growing season. CaO2, with or without molinate, increased rice grain yield 50% and increased rice culm density fivefold above untreated rice. Molinate applied ppi controlled 96% of the red rice. Rice seed coated with only CaO2or with CaO2plus R-33865 at 0.5%, each combined with ppi molinate, produced 5690 and 6030 kg/ha of grain, respectively. These high yields were associated with red rice control by molinate and good stands of rice provided by O2supplied by CaO2. R-33865 applied to rice seed at 1% (v/w) injured rice by reducing rice culm densities 41%, compared with rice without protectant.

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Improved Rice Technology Adoption: The Role of Spatially-Dependent Risk Preference

Agriculture ◽

10.3390/agriculture11080691 ◽

2021 ◽

Vol 11 (8) ◽

pp. 691

Author(s):

Omotuyole Isiaka Ambali ◽

Francisco Jose Areal ◽

Nikolaos Georgantzis

Keyword(s):

Field Experiments ◽

Climatic Factors ◽

Risk Preferences ◽

Risk Preference ◽

Probit Model ◽

Climatic Conditions ◽

High Yield ◽

Risk Attitudes ◽

Policy Action ◽

Rice Varieties

This study analyses farmers’ adoption of improved rice technology, taking into account farmers’ risk preferences; the unobserved spatial heterogeneity associated with farmers’ risk preferences; farmers’ household and farm characteristics; farm locations, farmers’ access to information, and their perceptions on the rice improved varieties (i.e., high yield varieties, HYV). The study used data obtained from field experiments and a survey conducted in 2016 in Nigeria. An instrumental-variable probit model was estimated to account for potential endogenous farmers’ risk preference in the adoption decision model. Results show that risk averse (risk avoidant) farmers are less likely to adopt HYV, with the spatial lags of farmers’ risk attitudes found to be a good instrument for spatially unobserved variables (e.g., environmental and climatic factors). We conclude that studies supporting policy action aiming at the diffusion of improved rice varieties need to collect information, if possible, on farmers’ risk attitudes, local environmental and climatic conditions (e.g., climatic, topographic, soil quality, pest incidence) in order to ease the design and evaluation of policy actions on the adoption of improved agricultural technology.

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