Loading...
Thesis
Browse
130 results
Search Results
ThesisItem Embargo Effect of different paired row arrangement on growth, yield and quality of kharif maize (Zea mays L.)(Punjab Agricultural University, 2024) Ashesh, Ayush; Dr. Harpreet SinghThe present study entitled “Effect of different paired row arrangement on growth, yield and quality of kharif maize (Zea mays L.)” was conducted at Regional Research Station (RRS), Gurdaspur and Punjab Agricultural University (PAU), Ludhiana during kharif 2022. The soil of Regional Research Station, Gurdaspur and Punjab Agricultural University, Ludhiana was clayey loam and sandy loam respectively and pH of soil at both the locations is neutral. The research was conducted in Randomized complete block design having twelve treatments and three replications. The hybrid variety used during research was PMH-13. The treatment comprise of 9 paired rows and 3 conventional methods at standard spacing of 60 cm x 20 cm. The paired rows are at different spacing where intra-paired rows are 20, 30 and 40 cm with inter-paired row distance of 60, 80 and 100 cm. Plant height significantly varied with planting population and paired spacing. The treatment with 20 cm intra-row spacing and 60 cm inter-row spacing consistently resulted in taller plants at various stages of growth. The treatment with 40 cm intra-row spacing and 100 cm inter-row spacing, which had the lowest population, exhibited significantly thicker stem girth. Days to reach tasseling and silking stages were not affected by different paired row arrangements and population densities. Leaf area index (LAI) was highest in the treatment with 20 cm intrarow spacing and 60 cm inter-row spacing, and a population of 125,000 plants ha-1. Photosynthetically active radiation (PAR) levels were significantly higher in the treatment with 20 cm intra-row spacing and 60 cm inter-row spacing, attributed to early and complete ground cover. Yield attributes like cob weight was not influenced by the treatments. However, cob length, cob girth, number of grains, and test weight were maximized in the treatment with 40 cm intra-row spacing and 100 cm inter-row spacing, with the lowest population. The highest grain yields were achieved with 20 cm intra-row spacing and 60 cm inter-row spacing, and a population of 125,000 plants ha-1. Similar yields were obtained with 40 cm intra-row spacing and 60 cm inter-row spacing, with a population of 100,000 plants ha-1. Nutrient and protein content in the plant were not significantly affected by the treatments. Stover yield was also higher in the treatment with 20 cm intra-row spacing and 60 cm inter-row spacing. Nitrogen, phosphorus, and potassium uptake were significantly higher for 20 cm intra-row spacing and 60 cm inter-row spacing due to increased dry matter accumulation. From economic perspective, the treatment with 40 cm intra-row spacing and 60 cm inter-row spacing was the most cost-effective option, with lower cultivation costs and higher net income at both the locations (PAU, Ludhiana and RRS, Gurdaspur).ThesisItem Restricted Management of nutrients and crop residue in rice-potatowheat cropping system(Punjab Agricultural University, 2024) Rose Maria Paul; Manhas, Surjeet SinghThe present study entitled “Management of nutrients and crop residue in rice-potato-wheat cropping system” was conducted at Students’ Research Farm, Department of Agronomy, Punjab Agricultural University, Ludhiana during 2022-23. The research was conducted in a split plot design having three main plot treatments and four subplot treatments with three replications. The main plot treatments included rice + wheat + potato residue + FYM @ 12.5 t ha-1, rice residue + FYM @ 25 t ha-1 and without residue + FYM @ 50 t ha-1. The subplot treatments included 75% RDN & P, 75% RDN, 50% RDN & P and 50% RDN. The growth parameters of wheat such as plant height, dry matter accumulation and the number of tillers m-2 were significantly higher with treatment without residue + FYM @ 50 t ha-1 than the rice + wheat + potato residue + FYM @ 12.5 t ha-1. The treatment 75% RDN & P resulted significantly higher growth parameters than 50% RDN but at par with 75% RDN and 50% RDN & P. Similarly, the yield attributes such as number of spikes, spike length, number of spikelets spike -1 and number of grains spike-1 were significantly more with without residue + FYM @ 50 t ha-1. 75% RDN & P had the highest results for yield attributes of wheat but was at par with 75% RDN and 50% RDN & P. The grain yield and harvest index of wheat were significantly higher with without residue + FYM @ 50 t ha-1. Furthermore, there was a 14.25% and 11.1% increase in grain yield over the rice + wheat + potato residue+ FYM @ 12.5 t ha-1 and rice residue + FYM @ 25 t ha-1 treatments respectively. However, the treatments had non-significant on quality parameters of wheat. The NPK uptake by grains was significantly more with treatment without residue + FYM @ 50 t ha-1 compared to rice + wheat + potato residue + FYM @ 12.5 t ha-1. Additionally, the grain NPK uptake was significantly higher with 75% RDN & P compared to 50% RDN but at par with 75% RDN and 50% RDN & P. The micronutrient content in grain and straw such as Fe, Zn, Mn and Cu was significantly higher as a result of the treatment without residue + FYM @ 50 t ha-1. However, the different levels of nutrient application had a non-significant effect on micronutrient content in grains. Furthermore, the soil parameters such as pH, EC and organic C were also unaffected by the treatments however, there was an increment in the organic C over the initial years. The soil available NPK was significantly higher with the treatment without residue + FYM @ 50 t ha-1 compared to rice + wheat + potato residue + FYM @ 12.5 t ha-1 whereas only soil N & P was significantly affected by the fertilizer treatments 75% RDN & P. Additionally, the soil micronutrients such as Fe, Zn, Mn and Cu was significantly more with without residue + FYM @ 50 t ha-1 compared to rice + wheat + potato residue + FYM @ 12.5 t ha-1. Potato crop, treatment without residue + 100 RDF + FYM @ 50 t ha-1 demonstrated the highest growth parameters such as plant height, DMA, number of haulms plant-1 and yield and the yield attributing factors like the number of tubers plant-1 and tuber weight and protein and starch content but the difference were non-significant compared to other treatments. Similarly, the treatments had a non-significant effect on the rice. Nevertheless, the treatment without residue + FYM @ 50 t ha-1 demonstrated higher results for growth parameters and yield and yield attributing characters of rice.ThesisItem Embargo Optimizing sub-surface drip fertigation system for better productivity and resource use efficiency of cotton-wheat cropping system(Punjab Agricultural University, 2024) Vaddula Yamini; Kulvir SinghSustainability concerns have loomed over cotton-wheat cropping system (CWCS) as conventional irrigation and fertilization methods have been resulting in huge wastage of water besides leaching of nutrients. This has stimulated an interest in sub-surface drip fertigation (SSDF), which could serve as transformative solution offering precise nutrient and water delivery to the crop. Therefore, a two-year field study was conducted during 2021-22 and 2022-23 at PAU, Regional Research Station, Faridkot to optimize lateral depth, emitter spacing and fertigation scheduling for sub-surface drip fertigated cotton-wheat cropping system. Experiment was laid out in a Split-Plot Design with a combination of lateral depths (25 ± 2.5 cm and 30 ± 2.5 cm) and emitter spacings (30 and 40 cm) in main plots and fertigation schedules [100% N (112.5 kg ha-1) and 125% N in 10 and 14 equal splits (cotton); 80 and 100% NP (100:50 kg NP ha-1) in 08 & 10 equal splits (wheat)] in sub plots. Two additional control treatments i.e., (surface flood irrigation with 100% RDF through manual broadcasting of fertilizers and SSDF at 20 ± 2.5 cm depth, 20 cm emitter spacing, and 100% RD N for cotton, and 80% RD NP for wheat) were also studied. Placing sub-surface drip laterals at 25 ± 2.5 cm and emitter spacing of 30 cm increased seed cotton yield by 15.4 and 8.7 per cent, and wheat grain yield by 7.7 and 3.7 per cent, respectively as compared with the deeper lateral placement (30 ± 2.5 cm) and wider emitter spacing (40 cm). Among fertigation levels, application of 125% N in 14 equal splits recorded 18.6 per cent higher SCY (3432.2 kg ha-1) over 100% N delivered in 10 equal splits (2895.1 kg ha-1). The productivity of CWCS under SSDF was improved by 18.6 per cent, when cotton and wheat were fertigated with 125% N in 14 equal splits and 100% NP in 10 equal splits, respectively in comparison to 100% N applied in 10 equal splits (cotton) and 80% NP application in 08 equal splits (wheat). Sub-surface drip fertigation with 125% N in 14 equal splits improved net returns by 49.7-54.2 per cent, besides saving 57.4-58.8 per cent of irrigation water relative to surface flood irrigation in cotton. Whereas, fertigation with 100% NP in 10 equal splits improved net returns by 21.6-16.2 per cent, additionally saving irrigation water by 45.9-47.7 per cent as compared with surface flood irrigation in wheat. Furthermore, lateral placement (25 ± 2.5 cm), emitter spacing (30 cm), and higher fertigation level [125% N in 14 equal splits (cotton) and (100% NP in 10 equal splits (wheat)] improved crop, irrigation and total water productivity indices by 1.3, 3.1, and 2.1 folds, respectively as compared with surface flood, accentuating the inefficient use of applied water by surface flood method of irrigation. These findings elucidated that SSDF with lateral placement of 25 ± 2.5 cm, emitter spacing of 30 cm, and N fertigation of 125% N (140 kg N ha-1) in 14 equal splits (cotton); 100% NP (125: 62.5 kg NP ha-1) in 10 equal splits (wheat) could be a novel and sustainable water-savvy concept in improving the growth and productivity of cotton-wheat cropping system in North-Western India.ThesisItem Embargo Effect of irrigation scheduling on yield, quality and water productivity of direct seeded and transplanted canola quality oilseed rape (Brassica napus L.)(Punjab Agricultural University, 2023) Jashanpreet Kaur; Sardana, VirenderA field experiment was conducted during rabi 2022-23 at the Punjab Agricultural University, Ludhiana to study the effect of sowing and transplanting dates, and irrigation scheduling on growth, yield, quality of oil and seed meal and water productivity of canola oilseed rape (Brassica napus L.). The experiment was laid out in split plot design in three replications with six combinations of three dates (10 October, 30 October and 20 November) and two methods of crop establishment (direct sowing and transplanting) in main plots and four irrigation schedules (IW:CPE 0.8, 1.0, 1.2 and irrigation based on crop growth stages) in sub plots. Soil of the experimental field was sandy loam. Canola oilseed rape variety GSC 7 was sown/transplanted at 45 cm × 10-12 cm spacing. Thirty days old seedlings were used for transplanting. Results revealed that with delay in sowing/transplanting from 10 October to 30 October to 20 November, number of days required for emergence and initiation of flowering significantly increased and for physiological maturity decreased. Delay in sowing/transplanting caused significant reduction in plant height, dry matter accumulation (DMA) and PAR (photosynthetically active radiation) interception at different growth stages, main shoot length, primary branches and siliquae plant-1, seeds siliqua-1 and 1000 seed weight. Crop sown/transplanted on 10 October produced 16.8%, 18.4%, 15.0% and 18.5% higher seed, stover, oil and protein yield than 30 October sown/transplanted crop which in turn significantly out yielded 20 November sown/transplanted crop by 60.0%, 30.2%, 62.9%, 66.1% for seed, stover, oil and protein yields, respectively. Crop sown/transplanted on 20 November contained significantly lower oleic and linolenic acid in oil and significantly higher glucosinolates in defatted seed meal as compared to 10 and 30 October sowing/transplanting dates. Real-, apparent- and total- water productivity decreased with delay in sowing/transplanting. Transplanted crop took significantly less number of days for initiation of flowering and physiological maturity, attained significantly more plant height, DMA and PAR interception at different growth stages and SPAD values up to 80 DAS/DAT, number of siliquae plant-1 and seeds siliqua-1 and seed oil content than direct sown crop. Transplanted crop produced 12.2%, 13.3%, 11.9% and 17.4% higher seed, stover, oil and protein yields than direct sown crop. Apparent- and total- water productivity of direct sown crop was significantly higher than transplanted crop. Application of irrigations at IW:CPE 1.2 resulted in significantly higher plant height, DMA and PAR interception, SPAD values at different growth stages, siliquae plant-1 and seeds siliqua-1 than other irrigation treatments. Irrigations at IW:CPE 1.2 resulted in significantly higher seed protein but lower proline content and total sugars than other irrigation treatments. Irrigations at IW:CPE 1.2 resulted in significantly higher seed yield as compared to the IW:CPE 0.8. Application of irrigations at IW:CPE 1.2 resulted in significantly higher oleic, linoleic and linolenic acid in oil and significantly lower glucosinolates in defatted meal as compared to other irrigation treatments. Irrigations at IW:CPE 0.8 resulted in significantly higher apparent- and total- water productivity. Seed and oil yield of crop transplanted on 30 October was at par with direct sown crop on 10 October. Crop transplanted on 30 October and 20 November produced significantly higher seed yield and oil yield than its direct sowing.ThesisItem Restricted Growth, water productivity and root architecture of rice-wheat cropping system under different methods of irrigation(Punjab Agricultural University, 2023) Navdeep Singh; Brar, Ajmer SinghA study entitled “Growth, water productivity and root architecture of rice-wheat cropping system under different methods of irrigation” was conducted during kharif and rabi, 2020 at the research farm of Department of Agronomy, Punjab Agricultural University, Ludhiana, Punjab. Soil was loamy sand in texture. Experiment was carried out in a randomized complete block design (RCBD) with 14 treatments with two methods of irrigation [surface drip (SD) and subsurface drip (SSD)] having two methods of sowing [direct seeded (DSR) and transplanted rice (PTR), followed by wheat in these plots] and three levels of irrigation (140%, 160%, 180% ETc in rice and 60%, 80% and 100% ETc in wheat) and 2 control (flood DSR followed by wheat with PAU recommendation and flood PTR followed by wheat with PAU recommendation). The grain yield of rice was statistically similar between DSR control and 180% ETc irrigated with either SSD or SD, established as DSR or PTR. DSR with 180% ETc in SSD saved 26% irrigation water as compared to DSR flood, 33% water as compared to PTR flood and 1.8% water in comparison to SSD PTR 180% ETc. Grain yield of wheat irrigated with 80% ETc was statistically at par with 100% ETc but it saved 17.1% water as compared to 100% ETc and 42% in comparison to flood. Root characteristics were not statistically affected with irrigation methods, establishment methods and irrigation levels in rice and wheat. System productivity was statistically at par between 180% ETc rice-100% ETc wheat and 160% ETc rice- 80 ETc wheat.ThesisItem Open Access Effect of agronomic manipulations on crop productivity and weed dynamics in poplar (Populus deltoides Bartr.) based agroforestry system(Punjab Agricultural University, Ludhiana, 2022) Parija, Bhadra; Navneet KaurPresent study entitled “Effect of agronomic manipulations on crop productivity and weed dynamics in poplar (Populus deltoides Bartr.) based agroforestry system” was carried out at Punjab Agricultural University, Ludhiana and KVK, Roopnagar (Experiment I) during 2017- 18 and 2018-19. Experiment I consisted of crop establishment methods of wheat viz. two methods of sowing (line sowing and broadcasting) and two seed rates (100 kg/ha and 125 kg/ha) along with five weed control treatments viz. carfentrazone 20 g/ha, pinoxaden 50 g/ha, clodinafop+metribuzin 270 g/ha, weed free check and weedy check in factorial RBD with 3 replications. The age of the poplar tree was 4 years in Ludhiana with 12.4 m height and 15.8 cm diameter at breast height (dbh) while at Roopnagar the age of the plantation was 3 years with an average 9.3 m height and 12.1 cm dbh during 2018-19. Experiment II consisted of planting geometry viz. two poplar spacings (8m×2.5m and 7m×3m, paired at 2.5m) and two potato planting geometry (65cm×18.5cm and 75cm×15cm) in main plots and weed control treatments (atrazine 0.250 kg/ha, metribuzin 0.350 kg/ha, paraquat 0.300 kg/ha, clodinafop+metribuzin 0.270 kg/ha, weed free check and weedy check) in sub-plots with three replications in split-plot design. The age of the poplar here was 6 years old with 19.6 m height and 26.5 cm DBH during 2018-19. The results of experiment I revealed that line sown wheat (38.0-42.8 q/ha) with higher seed rate of 125 kg/ha (37.3-41.5 q/ha) under weed free check (40.2-45.4 q/ha) had higher yield advantages with a greater number of effective tillers, spike length, grains/ear and 1000-grain weight in comparison to broadcasted with lower seed rate wheat crop under the rest weed control treatments and it was statistically at par with clodinafop+metribuzin 270 g/ha (36.5-41.3 q/ha) applied treatments. The application of clodinafop+metribuzin 270 g/ha effectively reduced the weed count and biomass. In experiment II, poplar spacing of 8m×2.5m (263.5-272.0 q/ha) and potato planting geometry of 75cm×15cm (256.6-262.1 q/ha) recorded significantly higher potato tuber yield. Among the weed control treatments weed free check (294.9-302.9 q/ha) was at par with clodinafop+metribuzin 0.270 kg/ha (289.4-293.2 q/ha) in terms of potato tuber no., weight/hill and yield. These treatments have exhibited a higher weed smothering effect thereby subsequently reduced the weed seed bank and seed recruitment in both the experiments. All the herbicides used in both the experiments temporarily reduced the microbial population and their activity upto 90 days of application and then it recovered till harvesting of the intercrops.ThesisItem Open Access In-situ rice residue management and its effect on growth and tuber yield of potato (Solanum tuberosum L.)(Punjab Agricultural University, Ludhiana, 2021) Jasneen Kaur; Harmeet SinghThe present investigation entitled “In-situ rice residue management and its effect on growth and tuber yield of potato (Solanum tuberosum L.)” was carried simultaneously out at two different locations viz. Students’ Research Farm, Department of Agronomy, Punjab Agricultural University, Ludhiana and Krishi Vigyan Kendra, Moga during autumn season of 2019-20. Soil of the experimental field at PAU, Ludhiana was sandy loam in texture with average bulk density of 1.45 g cm-3, normal in reaction (pH 7.40) and electrical conductivity (0.224 ds m-1), low in organic carbon (0.36 per cent) and low in available soil nitrogen (169.4 kg ha-1) and medium in available soil phosphorous (19.6 kg ha-1) and available soil potassium (206.4 kg ha1 ). While at Moga, soil was clay loam in texture with average bulk density of 1.37 g cm-3, normal in reaction (pH 8.1) and electrical conductivity (0.416 ds m-1), medium in organic carbon (0.51 per cent), low in available soil nitrogen (244.6 kg ha-1), high in available soil phosphorous (25.2 kg ha-1) and medium in available soil potassium (286.9 kg ha-1). Present field experiment laid out in strip plot design comprised of twelve treatments which included two straw load treatments which consisted of control (no loose straw) and 7 tonnes/ha straw load in vertical plots and three machinery operations which included harvesting by combine fitted with SMS + Mulcher + Reversible Mould Board Plough + Rotavator, harvesting by combine fitted with SMS + Reversible Mould Board Plough + Rotavator, harvesting by combine fitted with SMS + Disc Harrow + Rotavator and two depth of ploughing (shallow and deep) in horizontal plots with four replications. The results revealed that significantly higher number of plants emerged with straw load of 7 tonnes/ha, harvesting by combine fitted with SMS + Mulcher + Reversible Mould Board Plough + Rotavator machinery operation and deep ploughing treatment. At 70 DAP and maturity, plant height, dry matter accumulation by haulms and tubers, Leaf Area Index were recorded significantly higher with 7 tonnes/ha straw load, harvesting by combine fitted with SMS + Mulcher + Reversible Mould Board Plough + Rotavator machinery operation and deep ploughing treatments. However, plant height, dry matter accumulation by haulms and tubers and Leaf Area Index were not significantly affected at 35 DAP among different treatments. The treatment where 7 tonnes/ha straw load was added produced tuber yield of 27.0 t/ha at Ludhiana which 7.1 per cent higher than control (no loose straw) and at Moga, the tuber yield was 23.5 t/ha which was 8.2 per cent higher than control (no loose straw) treatment. Among machinery operations, harvesting by combine fitted with SMS + Mulcher + Reversible Mould Board Plough + Rotavator machinery operation resulted in 10.9 and 15.6 per cent higher tuber yield at Ludhiana and Moga, respectively than harvesting by combine fitted with SMS + Disc harrow + Rotavator machinery operation. Deep ploughing recorded 12.2 and 7.3 per cent higher tuber yield at Ludhiana and Moga, respectively than shallow ploughing. Similar trend was found for other yield attributes (number of tubers per plant, tuber weight per plant and tuber grading) as for tuber yield was recorded at both the locations. Straw load, machinery operations and depth of ploughing treatments showed no significant influence on chlorophyll index, soil physical and chemical properties (soil pH, electrical conductivity, organic carbon, bulk density, soil strength and infiltration rate) after harvest of potato, available soil nitrogen, phosphorous and potassium at 35 DAP, 70 DAP and maturity. Quality parameters failed to show any significant improvement with incorporation of straw load, machinery operations and depth of ploughing treatment. Soil moisture content was found to be significantly affected under different treatments at both the locations at all the stages except at 35 DAP. However, soil temperature was found non-significant under different machinery operations at Ludhiana but was found significant at Moga except at 35 DAP. Higher gross returns, higher net returns with higher benefit cost ratio was obtained when straw load of 7 tonnes/ha was added, harvesting by combine fitted with SMS + Mulcher + Reversible Mould Board Plough + Rotavator machinery operation and deep ploughing treatment.ThesisItem Restricted Foliar nitrogen application under reduced sunlight intensity in rice (Oryza sativa L.)(Punjab Agricultural University, Ludhiana, 2021) Garima; Sandhu, Sandeep SinghThe study entitled, “Foliar nitrogen application under reduced sunlight intensity in rice (Oryza sativa L.)” was conducted at Department of Climate Change and Agricultural Meteorology, Punjab Agricultural University, Ludhiana and Krishi Vigyan Kendra, Bahowal, Hoshiarpur. The soil of experimental field was loamy sand in texture at both the locations, medium in organic carbon, available nitrogen, phosphorus and potassium at Ludhiana, high in organic carbon and available nitrogen and medium in available phosphorous and potassium at Hoshiarpur. The soil was normal in reaction at both the locations. The experiment was conducted in randomized block design with three replications. The 20 treatment combinations comprised of four levels of sunlight intensity (control, 50% reduction in sunlight light intensity from 15-45, 46-75 and 76-105 DAT) and five levels of foliar nitrogen application (control, spray of 3% urea before, midway, afterwards and midway-afterwards the reduction in sunlight intensity). Sunlight intensity was reduced by covering the plots from top (leaving the sides open) with green shade net capable of reducing 50% sunlight intensity. The shade net was placed with the help of GI pipe structures specially prepared for this purpose. Rice variety used in the experiment was PR 122. At harvest, the growth parameters like plant height was significantly increased when sunlight intensity was reduced from 46-75 DAT as compared to control and other parameters like number of tillers m-2 and dry matter accumulation were significantly decreased at harvest when sunlight intensity was reduced from 46-75 DAT as compared to control at both the locations. Maximum reduction in the yield attributes like number of effective tillers m-2, panicle length and number of grains panicle-1 was also observed when there was reduction in sunlight intensity from 46-75 DAT as compared to full sunlight intensity at both the locations. Significantly lowest grain yield (48.70 and 53.44 q ha-1 at Ludhiana and Hoshiarpur, respectively) as compared to other levels of the treatment was recorded with the reduction in sunlight intensity during 46-75 DAT. Reduction in sunlight intensity during any period caused a significant increase in chlorophyll content and minimum cooking time of milled rice, while it significantly decreased the elongation ratio of milled rice as compared to control. All other quality parameters were observed to vary statistically non-significantly with the reduction in the sunlight intensity. The application of foliar nitrogen before the reduction in the sunlight intensity recorded the highest values of growth parameters, yield attributes, grain and biological yield, chlorophyll content and the minimum cooking time of rice.ThesisItem Open Access Effect of agronomic manipulations on crop productivity and weed dynamics in poplar (Populus deltoides Bartr.) based agroforestry system(Punjab Agricultural University, Ludhiana, 2022) Parija, Bhadra; Navneet KaurPresent study entitled “Effect of agronomic manipulations on crop productivity and weed dynamics in poplar (Populus deltoides Bartr.) based agroforestry system” was carried out at Punjab Agricultural University, Ludhiana and KVK, Roopnagar (Experiment I) during 2017- 18 and 2018-19. Experiment I consisted of crop establishment methods of wheat viz. two methods of sowing (line sowing and broadcasting) and two seed rates (100 kg/ha and 125 kg/ha) along with five weed control treatments viz. carfentrazone 20 g/ha, pinoxaden 50 g/ha, clodinafop+metribuzin 270 g/ha, weed free check and weedy check in factorial RBD with 3 replications. The age of the poplar tree was 4 years in Ludhiana with 12.4 m height and 15.8 cm diameter at breast height (dbh) while at Roopnagar the age of the plantation was 3 years with an average 9.3 m height and 12.1 cm dbh during 2018-19. Experiment II consisted of planting geometry viz. two poplar spacings (8m×2.5m and 7m×3m, paired at 2.5m) and two potato planting geometry (65cm×18.5cm and 75cm×15cm) in main plots and weed control treatments (atrazine 0.250 kg/ha, metribuzin 0.350 kg/ha, paraquat 0.300 kg/ha, clodinafop+metribuzin 0.270 kg/ha, weed free check and weedy check) in sub-plots with three replications in split-plot design. The age of the poplar here was 6 years old with 19.6 m height and 26.5 cm DBH during 2018-19. The results of experiment I revealed that line sown wheat (38.0-42.8 q/ha) with higher seed rate of 125 kg/ha (37.3-41.5 q/ha) under weed free check (40.2-45.4 q/ha) had higher yield advantages with a greater number of effective tillers, spike length, grains/ear and 1000-grain weight in comparison to broadcasted with lower seed rate wheat crop under the rest weed control treatments and it was statistically at par with clodinafop+metribuzin 270 g/ha (36.5-41.3 q/ha) applied treatments. The application of clodinafop+metribuzin 270 g/ha effectively reduced the weed count and biomass. In experiment II, poplar spacing of 8m×2.5m (263.5-272.0 q/ha) and potato planting geometry of 75cm×15cm (256.6-262.1 q/ha) recorded significantly higher potato tuber yield. Among the weed control treatments weed free check (294.9-302.9 q/ha) was at par with clodinafop+metribuzin 0.270 kg/ha (289.4-293.2 q/ha) in terms of potato tuber no., weight/hill and yield. These treatments have exhibited a higher weed smothering effect thereby subsequently reduced the weed seed bank and seed recruitment in both the experiments. All the herbicides used in both the experiments temporarily reduced the microbial population and their activity upto 90 days of application and then it recovered till harvesting of the intercrops.
