Behaviour of inter crop-growth stages scatterograms for NOAA/AVHRR vegetation indices

The effect of weed interference on corn yield and the critical period for weed control (CPWC) were determined in Germany and Benin. Treatments with weed control starting at different crop growth stages and continuously kept weed-free until harvest represented the “weed-infested interval.” Treatments that were kept weed-free from sowing until different crop growth stages represented the “weed-free interval.” Michaelis–Menten, Gompertz, logistic and log–logistic models were employed to model the weed interference on yield. Cross-validation revealed that the log–logistic model fitted the weed-infested interval data equally well as the logistic and slightly better than the Gompertz model fitted the weed-free interval. For Benin, economic calculations considered yield revenue and cost increase due to mechanical weeding operations. Weeding once at the ten-leaf stage of corn resulted already profitable in three out of four cases. One additional weeding operation may optimize and assure profit. Economic calculations for Germany determined a CPWC starting earlier than the four-leaf stage, challenging the decade-long propagated CPWC for corn. Differences between Germany and Benin are probably due to the higher yields and high costs in Germany. This study provides a straightforward method to implement economic data in the determination of the CPWC for chemical and nonchemical weed control strategies.

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TIME SERIES ANALYSIS OF REMOTE SENSING OBSERVATIONS FOR CITRUS CROP GROWTH STAGE AND EVAPOTRANSPIRATION ESTIMATION

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprsarchives-xli-b8-1037-2016 ◽

2016 ◽

Vol XLI-B8 ◽

pp. 1037-1042 ◽

Cited By ~ 1

Author(s):

S. A. Sawant ◽

M. Chakraborty ◽

S. Suradhaniwar ◽

J. Adinarayana ◽

S. S. Durbha

Keyword(s):

Remote Sensing ◽

Time Series ◽

Growth Stage ◽

Crop Growth ◽

Water Requirement ◽

Growth Stages ◽

Crop Water ◽

Horticultural Crops ◽

Crop Growth Stages ◽

Crop Growth Stage

Satellite based earth observation (EO) platforms have proved capability to spatio-temporally monitor changes on the earth's surface. Long term satellite missions have provided huge repository of optical remote sensing datasets, and United States Geological Survey (USGS) Landsat program is one of the oldest sources of optical EO datasets. This historical and near real time EO archive is a rich source of information to understand the seasonal changes in the horticultural crops. Citrus (Mandarin / Nagpur Orange) is one of the major horticultural crops cultivated in central India. Erratic behaviour of rainfall and dependency on groundwater for irrigation has wide impact on the citrus crop yield. Also, wide variations are reported in temperature and relative humidity causing early fruit onset and increase in crop water requirement. Therefore, there is need to study the crop growth stages and crop evapotranspiration at spatio-temporal scale for managing the scarce resources. In this study, an attempt has been made to understand the citrus crop growth stages using Normalized Difference Time Series (NDVI) time series data obtained from Landsat archives (<a href="http://earthexplorer.usgs.gov/"target="_blank">http://earthexplorer.usgs.gov/</a>). Total 388 Landsat 4, 5, 7 and 8 scenes (from year 1990 to Aug. 2015) for Worldwide Reference System (WRS) 2, path 145 and row 45 were selected to understand seasonal variations in citrus crop growth. Considering Landsat 30 meter spatial resolution to obtain homogeneous pixels with crop cover orchards larger than 2 hectare area was selected. To consider change in wavelength bandwidth (radiometric resolution) with Landsat sensors (i.e. 4, 5, 7 and 8) NDVI has been selected to obtain continuous sensor independent time series. The obtained crop growth stage information has been used to estimate citrus basal crop coefficient information (Kcb). Satellite based Kcb estimates were used with proximal agrometeorological sensing system observed relevant weather parameters for crop ET estimation. The results show that time series EO based crop growth stage estimates provide better information about geographically separated citrus orchards. Attempts are being made to estimate regional variations in citrus crop water requirement for effective irrigation planning. In future high resolution Sentinel 2 observations from European Space Agency (ESA) will be used to fill the time gaps and to get better understanding about citrus crop canopy parameters.

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Irrigation of field peas (Pisum sativum): response to timing at different crop growth stages

The Journal of Agricultural Science ◽

10.1017/s0021859699006516 ◽

1999 ◽

Vol 132 (4) ◽

pp. 417-424 ◽

Cited By ~ 1

Author(s):

C. M. KNOTT

Keyword(s):

Pisum Sativum ◽

Vegetative Growth ◽

Growth Stage ◽

Crop Growth ◽

Yield Response ◽

Growth Stages ◽

Field Peas ◽

Crop Growth Stages ◽

Different Growth Stages

The response of two cultivars of dry harvest field peas (Pisum sativum), Solara and Bohatyr, to irrigation at different growth stages was studied on light soils overlying sand in Nottinghamshire, England in 1990, when the spring was particularly dry, in 1991 which had a dry spring and summer and in contrast, 1992, when rainfall was greater compared with the long-term (40 year) mean.Solara, short haulmed and semi-leafless was more sensitive to drought than the tall conventional-leaved cultivar Bohatyr and gave a greater yield response to irrigation, particularly at the vegetative growth stage in the first two dry years 1990 and 1991, of 108% and 55% respectively, compared with unirrigated plots. Bohatyr was less sensitive to the timing of single applications.In all years, peas irrigated throughout on several occasions produced the highest yields, but this was the least efficient use of water.

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Estimation of Rice Yield Loss Using a Simple Linear Regression Model for Bacterial Blight Disease

Bangladesh Rice Journal ◽

10.3329/brj.v23i1.46083 ◽

2020 ◽

Vol 23 (1) ◽

pp. 73-79

Author(s):

T H Ansari ◽

M Ahmed ◽

S Akter ◽

M S Mian ◽

M A Latif ◽

...

Keyword(s):

Bacterial Blight ◽

Yield Loss ◽

Rice Variety ◽

Severity Index ◽

Susceptible Variety ◽

Crop Growth ◽

Grain Weight ◽

Growth Stages ◽

Crop Growth Stages ◽

1000 Grain Weight

Field experiment was carried out in hot and humid summer (Transplanted Aus) season to realize the yield loss of a susceptible rice variety Purbachi inoculated with bacterial blight (BB). Treatments consist of BB inoculations at different crop growth stages like maximum tillering (MT), panicle initiation (PI), booting (Bt), flowering and heading stages differently including a control (no BB inoculation). Disease severity index (DSI) was measured at 14 days after inoculation (DAI) and harvest. Data on 1000-grain-weight and yield was recorded at harvest. Significant variation on DSI was observed among different BB inoculated crop growth stages. MT, PI and Boot stage inoculations showed similar (DSI 7.1-8.0) but higher DSI than flowering and heading stages inoculation (3.2-5.3) even control (0.00) at 14 DAI. However, all the treatments showed similar DSI 9.0 at harvest. Bacterial blight can affect the grain weight to some extent although it was insignificant among the treatments (0.1-4.5%). DSI showed negative correlation with 1000-grain weight (r=-0.77*) and similarly with the yield (r=-0.97**). The yield ranged from 2.4-3.4 t/ha among the treatments. The yield loss was observed 5.8-30.4% in the BB inoculated treatments. MT, PI and Boot stages inoculation affected the yield much resulting 21-30.4% yield loss. It could be concluded that a susceptible variety can be affected with significant yield loss up to 30.4% with severe outbreak of B B. A simple regression equation = 4.09-0.211X( = Yield, X = BB severity score) is suggested for the prediction of yield loss in susceptible variety in summer season. Bangladesh Rice j. 2019, 23(1): 73-79

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Diquat residues in lentil following preharvest treatment

Canadian Journal of Plant Science ◽

10.4141/cjps91-057 ◽

1991 ◽

Vol 71 (2) ◽

pp. 413-418

Author(s):

Allan Cessna

Keyword(s):

Key Words ◽

Spectrophotometric Determination ◽

Analytical Method ◽

Lens Culinaris ◽

Growth Stage ◽

Crop Growth ◽

Growth Stages ◽

Limit Of Quantification ◽

Crop Growth Stages

In a 2-yr study, residues of diquat were spectrophotometrically determined in lentil (Lens culinaris Medik.) seed and straw/chaff following preharvest treatment using 0.56 kg ha−1 at three crop growth stages. Diquat residues ranged from 12.9 to 17.3 mg kg−1 in the lentil straw/chaff one day after application and decreased to 1.1 to 6.0 mg kg−1 2 wk later. Diquat residues in the seed were in the order of 0.05 mg kg−1 or less regardless of time of sampling after spraying or growth stage of the crop at application. The limit of quantification of the analytical method was 0.04 mg kg−1, and recoveries of diquat from fortified seed and straw were in the order of 70%. Key words: Diquat, lentil, residues, spectrophotometric determination

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TIME SERIES ANALYSIS OF REMOTE SENSING OBSERVATIONS FOR CITRUS CROP GROWTH STAGE AND EVAPOTRANSPIRATION ESTIMATION

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-archives-xli-b8-1037-2016 ◽

2016 ◽

Vol XLI-B8 ◽

pp. 1037-1042 ◽

Cited By ~ 1

Author(s):

S. A. Sawant ◽

M. Chakraborty ◽

S. Suradhaniwar ◽

J. Adinarayana ◽

S. S. Durbha

Keyword(s):

Remote Sensing ◽

Time Series ◽

Growth Stage ◽

Crop Growth ◽

Water Requirement ◽

Growth Stages ◽

Crop Water ◽

Horticultural Crops ◽

Crop Growth Stages ◽

Crop Growth Stage

Satellite based earth observation (EO) platforms have proved capability to spatio-temporally monitor changes on the earth's surface. Long term satellite missions have provided huge repository of optical remote sensing datasets, and United States Geological Survey (USGS) Landsat program is one of the oldest sources of optical EO datasets. This historical and near real time EO archive is a rich source of information to understand the seasonal changes in the horticultural crops. Citrus (Mandarin / Nagpur Orange) is one of the major horticultural crops cultivated in central India. Erratic behaviour of rainfall and dependency on groundwater for irrigation has wide impact on the citrus crop yield. Also, wide variations are reported in temperature and relative humidity causing early fruit onset and increase in crop water requirement. Therefore, there is need to study the crop growth stages and crop evapotranspiration at spatio-temporal scale for managing the scarce resources. In this study, an attempt has been made to understand the citrus crop growth stages using Normalized Difference Time Series (NDVI) time series data obtained from Landsat archives (<a href="http://earthexplorer.usgs.gov/"target="_blank">http://earthexplorer.usgs.gov/</a>). Total 388 Landsat 4, 5, 7 and 8 scenes (from year 1990 to Aug. 2015) for Worldwide Reference System (WRS) 2, path 145 and row 45 were selected to understand seasonal variations in citrus crop growth. Considering Landsat 30 meter spatial resolution to obtain homogeneous pixels with crop cover orchards larger than 2 hectare area was selected. To consider change in wavelength bandwidth (radiometric resolution) with Landsat sensors (i.e. 4, 5, 7 and 8) NDVI has been selected to obtain continuous sensor independent time series. The obtained crop growth stage information has been used to estimate citrus basal crop coefficient information (Kcb). Satellite based Kcb estimates were used with proximal agrometeorological sensing system observed relevant weather parameters for crop ET estimation. The results show that time series EO based crop growth stage estimates provide better information about geographically separated citrus orchards. Attempts are being made to estimate regional variations in citrus crop water requirement for effective irrigation planning. In future high resolution Sentinel 2 observations from European Space Agency (ESA) will be used to fill the time gaps and to get better understanding about citrus crop canopy parameters.

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INTEGRATION OF HUMAN PARTICIPATORY SENSING AND ARCHIVES OF REMOTE SENSING OBSERVATIONS FOR FIELD LEVEL CROP PHENOLOGY ESTIMATION

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-archives-xlii-4-547-2018 ◽

2018 ◽

Vol XLII-4 ◽

pp. 547-550

Author(s):

S. A. Sawant ◽

J. D. Mohite ◽

S. Pappula

Keyword(s):

Remote Sensing ◽

Time Series ◽

Vegetation Indices ◽

Crop Growth ◽

Growth Stages ◽

Growth Monitoring ◽

Specific Information ◽

Crop Phenology ◽

Field Level ◽

Sentinel 2

<p><strong>Abstract.</strong> The rise in global population has increased food and water demand thereby causing excessive pressure on existing resources. In developing countries with fragmented land holdings there exists constant pressure on available water and land resources. Obtaining field scale crop specific information is challenging task. Advent of open freely available multi-temporal remote sensing observations with improved radiometric resolution the possibilities for near real / real time applications has increased. In this study and an attempt has been made to establish operational model for field level crop growth monitoring using integrated approach of crowd sourcing and time series of remote sensing observations. The time series of Sentinel 2 (A and B) satellite has been used to estimate crop growth related components such as vegetation indices and crop growth stage and crop phenology. In initial stage high valued cereal crop Wheat has been selected. The field level information (i.e. 108 Wheat fields) collected using mobile based agro-advisory platform mKRISHI&reg; has been used to extract time series of Sentinel 2 observations (44 scenes for year 2016 and 2018). The moving average has been used for filling gaps in the time series of vegetation indices. The BFAST and GreenBrown package in R were used for detecting breaks in vegetation index time series and estimating crop growth stages. Analysis shows that the estimated crop phenology parameters were in better agreement with the field observations. In future more crops from different agro-climatic conditions will be considered for providing field level crop management advisory.</p>

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Dry Matter Production and Partitioning in Different Plant Parts of Rice Cultivars under Irrigation Regimes and Systems of Cultivation

Indian Journal of Agricultural Research ◽

10.18805/ijare.a-5316 ◽

2021 ◽

Author(s):

G.V. Venkataravana Nayaka ◽

G. Prabhakara Reddy ◽

R. Mahender Kumar

Keyword(s):

Dry Matter ◽

Crop Growth ◽

Dry Matter Production ◽

Growth Stages ◽

Rice Cultivars ◽

Wetting And Drying ◽

Alternate Wetting And Drying ◽

Irrigation Regimes ◽

Matter Production ◽

Crop Growth Stages

Background: Growth and yield characteristics of genotypes depend on genetic and environmental factors. Among the different production factors, varietal selection at any location plays an important role. Proper crop management depends on the growth characteristics of various varieties to get maximum benefit from new genetic material. Among the different water- saving irrigation methods in rice, the most widely adopted is alternate wetting and drying (AWD). Many of the rice cultivars vary in their performance under different systems of cultivation.Methods: A field experiment was conducted on a clay loam soil at Indian Institute of Rice Research (IIRR) Rajendranagar, Hyderabad, Telangana during the kharif seasons of 2017 and 2018. to study the “productivity and water use efficiency of rice cultivars under different irrigation regimes and systems of cultivation” The treatments consisted of two irrigation regimes Alternate wetting and drying and Saturation as main plot treatments, three establishment methods System of Rice Intensification (SRI), Drum Seeding (DS) and Normal transplanting (NTP) as sub plot treatments and four Cultivars namely DRR Dhan 42, DRR Dhan 43, MTU-1010 and NLR-34449 as sub-sub plot treatments summing up to 24 treatment combinations laid out in split-split plot design with three replications.Result: At 60, 90 DAS/DAT and harvest significantly dry matter production (DMP) was recorded with DRR Dhan 43 cultivar (607, 4320 and 11548 kg ha-1 respectively in pooled means of both 2017 and 2018) than other cultivars. Whereas MTU-1010 and NLR-34449 recorded on par dry matter production values at all the crop growth stages during both the years of study. However, DRR Dhan 42 produced the lowest dry matter production compared to other genotypes. DRR Dhan 43 recorded higher dry matter accumulation (g m-2) in root, stem and leaves at all the crop growth stages, during both the years of the study over other cultivars. Alternative wetting and drying method of irrigation recorded significantly higher DMP at all the growth stages of rice (60, 90 DAS/DAT and at harvest) except at 30 DAS/DAT during both 2017 and 2018 as compared to saturation. SRI recorded significantly higher DMP as compared to normal transplanting; however, it was comparably at par with drum seeding at all the growth stages.

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