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ThesisItem Restricted Weather based forewarning of wheat diseases using artificial neural networks under Punjab conditions(Punjab Agricultural University, 2023) Shubham Anand; Sandhu, Sarabjot KaurThe field experiments were carried out at the Research Experiment Farm, Department of Climate Change and Agricultural Meteorology, Punjab Agricultural University, Ludhiana and Regional Research Station, Gurdaspur during rabi seasons of 2021-22 and 2022-23. The experiment was laid out in Split Plot Design with three wheat varieties viz., PBW 725, HD 2967 and HD 3086 sown on different dates (14th-15th October, 8th-9th November and 3rd-4th December) with two microclimate modification levels M1 (recommended irrigation) and M2 (additional water sprays) with four replications. The micrometeorological parameters viz., photosynthetically active radiation (PAR) and relative humidity within crop canopy were recorded at different phenological stages. Weekly observations on severity of yellow rust, brown rust, foliar blight and incidence of Karnal bunt at harvest were determined under different treatments. Among the three different sowing dates, the yellow rust severity in variety HD 2967 was reported to be highest (56.14%, 56.17%) at Ludhiana and Gurdaspur (56.75%, 58.42%) in early sowing under M2 than other treatments during rabi 2021-22 and 2022-33, respectively. The brown rust severity was higher (65.44%, 68.21%) at Ludhiana and Gurdaspur (61.76%, 63.5%) in early sowing under M2 than other treatments during rabi 2021-22 and 2022-33, respectively. It was observed that early date of sowing (15th October) recorded higher foliar blight severity (28.52%, 29.35%) at Ludhiana and Gurdaspur (21.69%, 30.65%) in variety HD 3086 in M2 than other treatments during rabi 2021-22 and 2022-23. The Karnal bunt disease incidence was relatively higher at Ludhiana (17.9% and 11.6%) and Gurdaspur (21.4% and 15.9%) in variety PBW 725 under M2 during normal sowing than other treatments during both the years of study, respectively. From correlation coefficient and regression analysis, it was concluded that temperature (maximum and minimum), sunshine hours and rainfall were observed as key parameters in spread of wheat diseases. Grain yield during rabi 2021-22 and rabi 2022-23 were higher in early sowing (43.3q/ha, 48.1 q/ha) at Ludhiana and Gurdaspur (44.5 q/ha, 50.8 q/ha) than other dates of sowing during both the years under study. In variety x microclimate modification levels treatments, grain yield was higher (43.1q/ha, 47.2q/ha) at Ludhiana and Gurdaspur (44.0 q/ha, 50.2 q/ha) in variety PBW 725 under M1 than other treatments during both years under study. Early date of sowing recorded more yield losses followed by late and normal sowing and losses were more at Gurdaspur as compared to Ludhiana. Average yield losses during rabi 2022-23 were higher i.e. 5.6% and 7.1% as compared to 1.6% and 2.3% during rabi 2021-22 at Ludhiana and Gurdaspur, respectively. From in vitro study, it was observed that urediniospore germination of pathotypes of Puccinia striiformis and Puccinia triticina was maximum at 15°C and 20°C, respectively at pH 7.0 and 1250 lux light intensity. So, if high temperatures along with sunny days prevail rust can flourish in wheat fields. The random forest regression (RF) for February month, support vector regression (SVR) for March month, SVR and BLASSO for 15 February to 15 March period and random forest for overall period surpassed the performance than other models for forewarning of Karnal bunt. From the CART analysis, it can be inferred that maximum yellow rust severity can occur if >9.2 sunshine hours/day and >9.1oC minimum temperature occurs or, dew point temperature is >14oC and mean temperature is <15oC or dew point temperature is < 14oC and humid thermal index is <2.4.ThesisItem Open Access Optimizing productivity of maize under emission based climate scenarios by mid and end of 21st century in Punjab(Punjab Agricultural University, Ludhiana, 2022) Kothiyal, Shivani; Sidhu, Prabhjyot KaurThe study was conducted to analyse the maize yield and phenology under the future scenarios at different zones in Punjab. The CERES-Maize model was used to analyse the yield trend and observe the deviation of yield and phenological stages of two cultivars PMH1 and PMH2 during the mid-century (2021-50) and end-century (2066-95) from the baseline period (2010-2020). The CERES-Maize model was calibrated for the crop data collected under the mandatory trial of the “All India Co-ordinated Research Project on Agrometeorology” during 2018 and validated for the same trial during 2019. The calibration and validation results showed the simulated model results to be close to the observed with a low NRMSE (%) for both the cultivars PMH1 (1, 0.8, 3, 11.7) and PMH2 (0.9, 0.7, 2, 9) for anthesis, maturity, grain yield and LAI, respectively. The yield and LAI showed a polynomial relationship with the sowing window (20th May to 30th June) in Punjab with high grain yield peaks/ LAI during 20 May to 7 June as 5200-6000 kg ha-1/ 2.9-3.2 and 4200-5400 kg ha-1/ 2.8-3.0 respectively for varieties PMH1 and PMH2, respectively. The calibrated and validated model was used to study the future maize yield trend, deviation of yield and phenology from the baseline and optimization practices to avoid the negative effects. The maize yield and phenology of both the cultivars was analysed under the four scenarios RCP2.6, RCP4.5, RCP6.0 and RCP8.5 using the weather data of four GCMs (CSIRO-Mk-3-6-0, FIO-ESM, IPSL-CM5A-MR and Ensemble). The simulated maize yield trend for the current sowing dates showed a strong deviation at agroclimatic zone II (upto 94% and 77%), III (95% and 90%), IV (92% and 88%) and V (92% and 90%) for PMH1 and PMH2, respectively while the maturity for all the zones shortened by 25 days during the end-century under RCP8.5. The optimized sowing window (10th May to 14th July) was evaluated and the results showed the late dates of sowing to perform well at agroclimatic zone II and III while early sowing dates at V (Faridkot).The optimization of nitrogen doses (lower: 65kg ha-1; higher: 185 kg ha-1) showed slight yield increment at higher doses for agroclimatic zone II, III and V (Faridkot). Amongst the four GCMs, the FIO-ESM model overestimated the yield while the CSIRO-Mk-3-6-0 under estimated the yield. The optimization practices if used efficiently can help avoid climate change impact on maize crop in Punjab but only during mid-century under all the scenarios while under RCP8.5 during end-century no yield increment was observed.ThesisItem Open Access Spatio-temporal variability in evapotranspiration and its prediction under future climate change scenarios in Trans-gangetic plains(Punjab Agricultural University, Ludhiana, 2021) Sukhbeer Kaur; Kingra, P. K.The study entitled, “Spatio-temporal variability in evapotranspiration and its prediction under future climate change scenarios in Trans-gangetic plains” was conducted at the Department of Climate Change and Agricultural Meteorology, Punjab Agricultural University, Ludhiana. Reference evapotranspiration (ETO) for different districts of transgangetic plains was estimated by using Hargreaves-Samani method for the period 19702019 and for mid (2040-2060) and end-century (2075-2095) annually as well as for kharif and rabi season, which was used to estimate crop evapotranspiration (ETc), irrigation requirements (IR) and water productivity (WPET) for rice, wheat, maize and cotton crops. Annual ETO increased @ 1.23 mm/year during 1970-2019, @ 2.25 mm/year during midcentury and @ 2.10 mm/year during end-century for RCP 8.5. ETo increased @ 1.16 and 0.34 mm/year in kharif and @ 1.12 and 1.54 mm/year in rabi season during mid- and endcentury for RCP 8.5. Crop evapotranspiration increased significantly @ 0.61, 0.28, 0.74 and 0.49 mm/year during 1970-2019 for rice, wheat, cotton and maize respectively. For midcentury, crop evapotranspiration increased significantly under all the climate change scenarios being highest for RCP 8.5 @ 0.66, 0.63, 0.97 and 0.44 mm/year for rice, wheat, cotton and maize, respectively, during mid-century. However, for end-century, significant decrease was observed in ETc for RCP 2.6 for all crops. Similarly, irrigation requirements increased @ 0.48, 0.55, 0.72 and 0.28 mm/year for rice, wheat, cotton and maize, respectively, under RCP 8.5 during mid-century, but decreased significantly under RCP 2.6 during end century for all crops. Crop water productivity also increased significantly during 1970-2019 @ 0.04, 0.15 and 0.10 kg/ha/mm/year for rice, wheat and maize respectively. Both crop yield and water productivity were observed to decrease during mid-century and end-century with highest decrease under RCP 8.5 for all the crops. The study concluded that crop yield as well as water productivity will be severely affected due to climate change during mid and end-century.ThesisItem Open Access Impact of western disturbances on wheat (Triticum aestivum L.) crop in Punjab(Punjab Agricultural University, Ludhiana, 2020) Satinder Kaur; Gill, K.K.The present study entitled “Impact of western disturbances on wheat (Triticum aestivum L.) crop in Punjab” was carried out using and analyzing historical data, conducting field experiment and validating data using SPSS software. Data pertaining to historical weather parameters were studied for different districts of Punjab- Amritsar, Ludhiana, Bathinda, Ballowal, Faridkot and Patiala which showed that on an average for all the districts under study maximum onset and withdrawal of monsoon was observed in October and May, respectively. Further, total number of western disturbances was observed maximum in Day 1, followed by Day 2 and decreases subsequently. In addition to this it was also found that western disturbances was higher in January, February and March in comparison to other months of the growing season mostly in all the districts. Field experiment was conducted for two consecutive years during the rabi seasons of 2017-18 and 2018-19 at three locations, namely, Ballowal Saunkri, Ludhiana and Faridkot. The experiment was replicated thrice in a factorial split plot design with nine combinations of dates of sowing (25th October, 15th November and 5th December) and three varieties (WH1105, Unnat PBW550 and PBW590) in the main plots and two levels of irrigation (recommended and recommended± forecast based) in the subplots. Crop phenology was observed by visual observations. Micrometeorological parameters were recorded within the crop canopy at different phenological stages while biometric observations were recorded at 20 days interval. The results revealed that crop growth, yield and yield attributing characters were found highest under 15th November sowing at all the locations. Cultivar PBW590 found out to be poor performer when compared to other two varieties. Regression equations among different weather parameters and green yield of wheat were developed using SPSS software for different districts of Punjab in which R2 value ranged from 82.9 in Ludhiana to 99.9 in Bathinda. Further calibration and validation of data resulted in minimal error.ThesisItem Restricted Impacts of climate change on spatio-temporal variability in cropping patterns over trans-gangatic plains(Punjab Agricultural University, Ludhiana, 2018) Baljeet Kaur; Som Pal SinghIn the present study, analysis of spatial and temporal variation in climatic parameters and cropping patterns in trans-gangetic plains was carried out. The historical climatic data and data pertaining to area and productivity of wheat, rice and maize crops for the period 1971-72 to 2015-16 were employed for the investigation. The climatic data was analysed on the basis of decades, years and season using Mann Kendall and Sen’s slope statistics to examine the variability and trends over the study area. Spatial and temporal interpolations using Inverse Distance Weighted (IDW) method were used to develop the gradient of the data. Relative change in area of wheat, rice and maize was determined decade-wise. Step-wise regression was used to study the impact of climate change on wheat, rice and maize productivity. Under future climatic scenario RCP8.5, InfoCrop model was evaluated to project the wheat, rice and maize yields. During rabi season, higher rate of maximum and minimum temperature was observed for Haryana and central zone of Punjab. No trend was observed in rainfall in trans-gangetic plains. Rate of increase in maximum temperature was 0.063 oC for Haryana, 0.04 oC for northern Rajasthan and 0.049 oC for Delhi. Rate of increase in minimum temperature was 0.031oC for Punjab and 0.045 oC for Haryana. Area under wheat over TGP increased at the rate of 468 ha per decade significantly (R2 =0.92). It has increased by 24.68%, 80.93%, 9.39% and 39.80% in Punjab, Haryana, northern Rajasthan and TGP; respectively whereas area under wheat in Delhi decreased by 57.78% as compared with 1971-80. The analysis of area under rice and maize revealed that area under maize declined over the trans-gangetic plain region by 70.7% in 2016 compared with 1980. Per cent change in rice area was 157.6 in TGP. Wheat and maize productivity was affected negatively mostly by minimum temperature alone. Rice productivity showed positive relationship with increasing trends of temperature. Future projection of wheat, rice and maize showed that wheat productivity will decrease more in Punjab (R2=0.76) followed by Delhi (R2=0.72) and Haryana (R2=0.66). Decline in rice yield will be more in northern Rajasthan (R2=0.62) followed by Delhi (R2=0.58). More declines in maize will be in Haryana (R2= 0.77) under future climatic scenario.ThesisItem Restricted Assessment and management of climatic variability impact on evapotranspiration and water productivity of Maize (Zea mays L.) in Punjab(Punjab Agricultural University, Ludhiana, 2018) Harleen Kaur; Kingra, P.K.ABSTRACT The field experiment entitled, “Assessment and management of climatic variability impact on evapotranspiration and water productivity of maize (Zea mays L.) in Punjab” was carried out at the Research Farm of the Department of Climate Change and Agricultural Meteorology, Punjab Agricultural University, Ludhiana for two consecutive kharif seasons of 2016 and 2017. The field experiment comprising of 12 treatments was carried out in split plot design with 3 replications having three dates of sowing (D1-Third week of May, D2-Second week of June and D3- First week of July) in main plots and two irrigation levels i.e. irrigation at IW: CPE of 1.00 (I1) and 0.75 (I2) and two mulch levels viz. mulch @ 5 t ha-1 (M1) and no mulch (M2) in the sub-plots. The soil of the experimental site was loamy sand in texture with normal pH and electrical conductivity and low in organic carbon. PAR interception and relative humidity was highest in D2 as compared to D1 and D3 and among irrigation and mulch treatments in I2 and M1. The canopy temperature was highest in D3 as compared to D1 and D2 and among irrigation and mulch in I1 and M2 treatments at reproductive stage of crop. Higher plant height, dry matter and LAI was observed in the crop sown during second week of June and among irrigation and mulch treatments in I2 and M1. The total water use was more in D1 (540.5 and 477.5 mm) as compared to the D2 (493.3 and 399.0 mm) and D3 (415.1 and 316.3 mm) in 2016 and 2017, respectively. Among mulch and irrigation levels, the total water use was more in non-mulched crop (M2) and under IW/CPE=1.00 (I1).The yield attributing characters under D2 were statistically at par with D1 and significantly higher than D3 and among mulch and irrigation treatments in M1 and I2. During 2016, difference in grain yield under different dates of sowing was found to be non-significant. During 2017, the grain yield under D2 (52.37 q/ha) was at par with D1 (50.86 q/ha) but was significantly higher than D3 (41.04 q/ha). During 2017, among mulch levels, the grain yield was significantly higher in mulch applied crop (50.71 q/ha) as compared to non-mulched crop (46.14 q/ha). The water, heat and radiation use efficiency of maize was also found to be higher under D2, I2 and M1, during both the years. The priestley-taylor method gave higher ETo in all three dates of sowing and was closer to open-pan evaporation except in first date of sowing during 2016, in which ETo was higher in FAO-56 (602.4 mm). The crop coefficients calculated by Papadakis method were comparatively higher as compared to that calculated by other methods. Good agreement was observed between actual and simulated yield (R2=0.77 each) and water productivity (R2= 0.43 and 0.44) during both the crop growing seasons. Simulation results showed that water productivity of maize increased with increase in CO2 concentration and decreased with increase in temperature, but this decrease could be compensated by simultaneous increase in CO2 concentration.
