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Papers by sheeja raj

Agricultural Reviews, Jul 14, 2022

Millets are the traditional staple food of dry land regions and have the potential to contribute ... more Millets are the traditional staple food of dry land regions and have the potential to contribute substantially for food, fodder and the nutritional security. The millets are relatively poor competitors against weeds especially during the early growth stages due to their slow initial growth and wider spacing. Yield loss due to weeds in millets varies from 5 to 94 per cent depending on climatic, edaphic and biotic factors. Weeds compete with crops for nutrients, soil moisture, sunlight and space when they are limiting, resulting in reduction in yield, quality and increased cost of production. The objective of this paper is to review the research that have been conducted pertaining to various aspects of weed management in millets. The literature suggests that instead of relying on any single method of weed control, all the feasible methods are to be integrated for the effective and sustainable management of weeds in millets. Integrated weed management can effectively overcome the problems of weed shift and development of resistance in weeds and reduce the weed seed bank and manage the weeds below the economic threshold level to avoid any economic loss.

Journal of Crop and Weed, 2018

Field experiment was conducted at Coconut Research Balaramapuram, during Kharif 2017 to study the... more Field experiment was conducted at Coconut Research Balaramapuram, during Kharif 2017 to study the effect of nutrient levels and schedule of nutrient application on the yield and economics of upland rice intercropped in coconut. The experiment was conducted in RBD with four different nutrient levels and four different schedules of nutrient application. Nutrient levels significantly influenced the grain and straw yield, net returns and B: C ratio and the highest grain yield, straw yield, net returns and B: C ratio were recorded with the application of NPK @ 90:30:45 kg ha-1. Nutrient schedules also have significant effect on grain yield, net returns and B: C ratio. Among the schedule of nutrient application, N applied in three splits (15 days after sowing (DAS), active tillering and panicle initiation stage), P as basal and K in two equal splits (15 DAS and panicle initiation stage) along with foliar application of 0.2 per cent zinc sulphate and 0.04 per cent sodium borate recorded the highest grain yield, net returns and B:C ratio. Interaction between nutrient levels and schedule of nutrient application was also found significant. NPK @ 90:30:45 kg ha-1 , applied as N in three equal splits (15 DAS, active tillering and panicle initiation stage), P as basal and K in two equal splits (15 DAS and panicle initiation stage) along with foliar application of 0.2 per cent zinc sulphate and 0.04 per cent sodium borate at 45 DAS recorded higher grain yield, net returns and B:C ratio and can be recommended for upland rice raised as intercrop in coconut.

Agricultural Reviews, Nov 7, 2022

Carbon sequestration plays a significant part in alleviating climate change by changing over clim... more Carbon sequestration plays a significant part in alleviating climate change by changing over climatic carbon as plant biomass and soil organic carbon. Since trees can hold greater carbon in their biomass than other plant types, perennial plantations have a vital function in mitigating the advers ities in c limate. Coc onut is a perennial palm with a life time of around 50-60 years has the capability to store carbon for a long time, especially in the stem. Due to the increased availability of space and solar radiation reaching the understorey, the carbon sequestration capacity of coconut plantations can be considerably increased. As a result, intercropping or agroforestry in coconut lands is important not only for food and economic security but also for carbon sequestration. On an average carbon sequestration potential of coconut trees range between 37 kg tree-1 yr-1 (dwarf variety) up to 56 kg tree-1 yr-1 (tall variety). After 20 years of establishment, monoculture coconut land can be transformed into perennial mixed cropping or agroforestry system that can sequester more carbon.

Indian Journal of Weed science, 2023

Agricultural Reviews

Melochia corchorifolia L. commonly known as ‘Chocolate weed’ is an annual herbaceous troublesome ... more Melochia corchorifolia L. commonly known as ‘Chocolate weed’ is an annual herbaceous troublesome weed found in cultivated land across the world. ‘Eradication by Utilization’ could be employed as an effective means of managing Melochia corchorifolia. Plant extracts of Melochia corchorifolia can be utilized for the control of the storage pest, Callosobruchus maculatus. Active fraction of the plant extract along with neem oil and karanj oil could be used to prepare botanical pesticides. Several phytochemicals having pharmacological properties have been identified from the plant extracts of Melochia corchorifolia. Being a good source of minerals and nutrients, the fresh leaves are used as food and folk medicine in various parts of the world.

Indian Journal of Weed Science

Agricultural Reviews

Carbon sequestration plays a significant part in alleviating climate change by changing over clim... more Carbon sequestration plays a significant part in alleviating climate change by changing over climatic carbon as plant biomass and soil organic carbon. Since trees can hold greater carbon in their biomass than other plant types, perennial plantations have a vital function in mitigating the adversities in climate. Coconut is a perennial palm with a life time of around 50-60 years has the capability to store carbon for a long time, especially in the stem. Due to the increased availability of space and solar radiation reaching the understorey, the carbon sequestration capacity of coconut plantations can be considerably increased. As a result, intercropping or agroforestry in coconut lands is important not only for food and economic security but also for carbon sequestration. On an average carbon sequestration potential of coconut trees range between 37 kg tree-1 yr-1 (dwarf variety) up to 56 kg tree-1yr-1 (tall variety). After 20 years of establishment, monoculture coconut land can be t...

Agricultural Reviews

Millets are the traditional staple food of dry land regions and have the potential to contribute ... more Millets are the traditional staple food of dry land regions and have the potential to contribute substantially for food, fodder and the nutritional security. The millets are relatively poor competitors against weeds especially during the early growth stages due to their slow initial growth and wider spacing. Yield loss due to weeds in millets varies from 5 to 94 per cent depending on climatic, edaphic and biotic factors. Weeds compete with crops for nutrients, soil moisture, sunlight and space when they are limiting, resulting in reduction in yield, quality and increased cost of production. The objective of this paper is to review the research that have been conducted pertaining to various aspects of weed management in millets. The literature suggests that instead of relying on any single method of weed control, all the feasible methods are to be integrated for the effective and sustainable management of weeds in millets. Integrated weed management can effectively overcome the probl...

Agricultural Science Digest - A Research Journal

Background: Weeds are the major biological constraint in okra due to its slow initial growth and ... more Background: Weeds are the major biological constraint in okra due to its slow initial growth and wider row spacing. Due to severe crop weed competition, weeds removed considerable amount of nutrients from the soil. Competition exists between the crop and weed for nutrients results in nutrient deficiencies in crop. Hence the present experiment is formulated to assess the effect of stale seedbed, mulching and mechanical weeding on nutrient availability, nutrient uptake by crop and weed in okra. Methods: Experiment was conducted at Coconut Research Station, Balaramapuram, Thiruvananthapuram, Kerala during Rabi 2020-21. Design adopted for the study was RBD with two factors. The first factor was seedbed preparation (S) and the second factor was weed management (W). Stale seedbed (S1) and normal seedbed (S2) were the two different seedbed preparation methods and dried banana leaf mulch @10 t ha-1 alone (W1), dried banana leaf mulch @10 t ha-1 fb wheel hoe weeding at 30 and 45 DAS (W2), dr...

Journal of Crop and Weed, 2020

The site was located at 8°22'52" North latitude and 77°1' 47" East longitude and at an altitude o... more The site was located at 8°22'52" North latitude and 77°1' 47" East longitude and at an altitude of 9 m above mean sea level. A warm humid climate prevailed over the experimental site. The data on daily weather parameters like mean temperature, relative humidity (RH), rainfall and evaporation were noted from the Class B Agromet observatory attached to the site. The rainfall received during the crop season was 952.3 mm. The soil texture was sandy loam with acidic pH (4.6). The soil had medium organic carbon (0.79%), N (301.50 kg ha-1), P (21.10 kg ha-1) and low K (93.07 kg ha-1) status.

Journal of Applied and Natural Science, 2018

Micronutrients, though needed in smaller amounts, play a major role in the production and product... more Micronutrients, though needed in smaller amounts, play a major role in the production and productivity of rice. Zn is the fourth most deficient nutrient element in Indian soils and its deficiency causes severe yield reduction in rice. Application of Zn either as foliar spray or soil application caused significant improvement in growth and yield attributes and yield of rice. Similar to that of Zn, B nutrition also caused significant improvement in growth and yield attributes and yield of rice. The review elaborates the effect of Zn and B nutrition on the growth, physiological parameters, yield attributes, yield and quality of rice.

International Journal of Chemical Studies, 2021

A study was conducted to determine the soil quality and changes in the fertility status of soils ... more A study was conducted to determine the soil quality and changes in the fertility status of soils after 2018 flood in Agro-ecological unit (AEU) 9 in Pathanamthitta district of Kerala and GIS maps were generated. A survey was conducted in the study area and seventy five geo referenced soil samples were collected from flood affected panchayaths. The samples were analysed for pH, organic carbon, N, P, K, Ca, Mg, S and micronutrients and GIS based thematic maps were prepared. The results of the study revealed that pH of soil falls into very strongly acidic, strongly acidic and moderately acidic categories after flood. Organic carbon and available K were increased and available P slightly decreased after the floods and widespread deficiency of available nitrogen were observed. Calcium and magnesium status also low in post flood soils. Among the micronutrients boron was highly deficient. The results outline the need for regular liming to control soil acidity and to alleviate Ca deficiency. The soils should be supplemented with Mg and B in addition to recommended dose of N, P and K fertilizers. Soil quality index of the postflood soils of AEU 9 was calculated from eight parameters of minimum data set viz., organic carbon, bulk density, available K, available B, available S, sand percent and manganese. Majority of the soils had high soil quality index of more than 70.

Agricultural Reviews, May 4, 2022

Weeds are the major biological constraint in oilseed crops. Yield loss in oilseeds vary from 20 t... more Weeds are the major biological constraint in oilseed crops. Yield loss in oilseeds vary from 20 to 77 per cent, depending on the crop, intensity of weed infestation, duration of crop competition, soil and climatic factors. Weed interference, not only reduces the seed yield, but also reduces the oil yield and quality. Critical period of weed control in oilseeds are generally from 15 to 45 DAS. Weed removal during the critical period is essential to reduce the yield loss. Hike in wage rate and phytotoxicity of herbicides calls for an integrated approach for weed management in oilseeds. Instead of relying on a single method, a holistic approach which involves the adoption of cultural/mechanical/biological/chemical methods is essential to keep the weeds below the threshold level for higher yield, productivity and net returns in oilseed crops.

Journal of Crop and Weed, 2018

Bioassay tests were carried out at Department of Agronomy, College of Agriculture Vellayani durin... more Bioassay tests were carried out at Department of Agronomy, College of Agriculture Vellayani during 2014 and field experiments were carried out during kharif 2014 and rabi 2014-15 in farmers field at Kalliyoor Panchayat of Thiruvananthapuram district, Kerala. Response of three test crops, maize, cucumber and sunflower to penoxsulam + cyhalofop butyl revealed that maize was the most sensitive indicator plant and fresh shoot weight of maize was the most susceptible parameter to detect the phytotoxic residue of this herbicide in soil. Bioassay with maize plant in post experiment soil during both the seasons revealed that post emergence application of penoxsulam + cyhalofop even at a concentration of 135 g ha-1 did not cause any growth inhibition in fresh shoot and dry weight, shoot length and root length inferring that, the herbicide penoxsulam + cyhalofop butyl 6 % OD (oil dispersion) did not leave any phytotoxic residue in soil and is environmentally safe.

Research on Crops, 2015

The field experiments were conducted during kharif and rabi 2014 to study the efficacy of pre-mix... more The field experiments were conducted during kharif and rabi 2014 to study the efficacy of pre-mix herbicide mixture penoxsulam+cyhalofop butyl for weed control in direct seeded puddled rice. The experiment was laid out in randomized block design with eight treatments and three replications. The treatments comprised four different doses of penoxsulam+cyhalofop butyl 6% OD viz., 120, 125, 130 and 135 g a. i./ha, bispyribac sodium 10% SE 25 g a. i./ha, penoxsulam 24 SC 22.5 g a. i./ha, hand weeding twice and weedy check. On 30 days after sowing (DAS) weed flora comprised sedges (53.91%), broad leaf weeds (37.88%) and grasses (8. 2%) and on 60 DAS weed flora constituted sedges (53.15%), broad leaf weeds (BLW) (34.66%) and grasses (12.19%). The dominant weed species present in the experimental field were Schoenoplectus juncoides (Roxb.) Palla, Cyperus iria L. and Cyperus difformis L. among sedges; Isachne miliaceae Roth among grasses and Ludwigia perennis, Limnocharis flava (L.) Buch., Marsilea quadrifoliata L. and Bergia carpensis L. among broad leaf weeds. Pre-mix herbicide mixture, penoxsulam+cyhalofop butyl was found to be effective in reducing the density and dry weight of weeds at 30, 45 and 60 DAS. Among the doses, higher doses of penoxsulam+cyhalofop butyl (130 and 135 g a. i./ha) were found to be more effective in reducing the dry weight with a weed control efficiency of 97.34 and 98.31%, respectively. Higher growth and better expression of yield attributes were registered for these treatments. Adoption of weed control measures enhanced the grain yield from 4.26 to 8.46 t/ha. All the tested doses of penoxsulam+cyhalofop butyl recorded higher grain yield compared to hand weeding, penoxsulam and bispyribac sodium applied alone. Application of penoxsulam +cyhalofop butyl at its higher dose (135 g a. i./ha) recorded the highest grain yield which was on a par with its lower dose 130 g a. i./ha. The highest gross returns and B: C ratio were also recorded by these treatments. Bispyribac sodium was found to be less effective in reducing the density and dry weight of sedges resulting in lesser yield and B: C ratio compared to penoxsulam in the present study. Hand weeding recorded the lowest gross returns and B: C ratio among the weed control treatments. The study concludes that better broad spectrum control of weeds can be achieved by the post-emergence application of herbicide mixture penoxsulam+cyhalofop butyl on 15 DAS. The selection of herbicide and dose should depend on the target weed species in an area.

Madras agricultural journal, 2012

The Indian Journal of Agricultural Sciences, 2013

Journal of Crop and Weed, 2020

Field experiment was carried out to study the effect of stale seed bed and weed management practi... more Field experiment was carried out to study the effect of stale seed bed and weed management practices on nutrient uptake by weeds, nutrient uptake and green pod yield of bush type vegetable cowpea during Kharif season 2019 at Coconut Research Station, Balaramapuram. The experimental was conducted in randomized block design with two factors viz., factor A-seed bed preparation with two treatments and factor B-weed management practices with eight treatments in three replications. Stale seed bed recorded the lowest total weed dry weight, NPK uptake by weeds and the highest NPK uptake by crop and green pod yield. Among the weed management practices, dried banana leaf mulch @ 10 t ha-1 fb quizalofop-p-ethyl @ 50 g ha-1 on 25 DAS recorded the lowest total weed dry weight, NPK uptake by weeds and the highest total N and P uptake by crop and green pod yield (7589.0 kg ha-1). Pre emergence diclosulam @ 12.5 g ha-1 fb hand weeding at 25 DAS recorded the highest K uptake by crop. Interaction effect revealed that the stale seed bed + dried banana leaf mulch @ 10 t ha-1 fb quizalofop-p ethyl @ 50 g ha-1 on 25 DAS recorded the highest N and P uptake by crop, number of pods per plant, pod weight and green pod yield. The lowest weed dry weight and the lowest NPK uptake by weeds was registered in stale seed bed + pre emergence application of diclosulam @ 12.5 g ha-1 fb hand weeding at 25 DAS.

Journal of Applied and Natural Science, 2018

Field experiment was conducted at Coconut Research Balaramapuram, during Kharif 2017 to study the... more Field experiment was conducted at Coconut Research Balaramapuram, during Kharif 2017 to study the effect of nutrient levels and schedule of application on the quality parameters of upland rice intercropped in coconut. The experiment was conducted in randomized block design (RBD) with four different nutrient levels and four different schedules of nutrient application. Quality parameters like crude protein and starch content were significantly influenced by nutrient levels. The crude protein content was found to increase with increase in N level, however starch content was found to increase up to 70 kg N and 35 kg K ha-1 and after that a decline in trend was observed. The highest crude protein content (8.38 per cent) was recorded with highest nutrient level, NPK @ 120:30:60 kg ha-1. However, lower nutrient level, NPK @ 70:30:35 kg ha-1 recorded higher starch content (85.03 per cent). Among the schedule of nutrient application, N applied in three equal splits (15 days after sowing (...

Agricultural Reviews, Jul 14, 2022

Millets are the traditional staple food of dry land regions and have the potential to contribute ... more Millets are the traditional staple food of dry land regions and have the potential to contribute substantially for food, fodder and the nutritional security. The millets are relatively poor competitors against weeds especially during the early growth stages due to their slow initial growth and wider spacing. Yield loss due to weeds in millets varies from 5 to 94 per cent depending on climatic, edaphic and biotic factors. Weeds compete with crops for nutrients, soil moisture, sunlight and space when they are limiting, resulting in reduction in yield, quality and increased cost of production. The objective of this paper is to review the research that have been conducted pertaining to various aspects of weed management in millets. The literature suggests that instead of relying on any single method of weed control, all the feasible methods are to be integrated for the effective and sustainable management of weeds in millets. Integrated weed management can effectively overcome the problems of weed shift and development of resistance in weeds and reduce the weed seed bank and manage the weeds below the economic threshold level to avoid any economic loss.

Journal of Crop and Weed, 2018

Field experiment was conducted at Coconut Research Balaramapuram, during Kharif 2017 to study the... more Field experiment was conducted at Coconut Research Balaramapuram, during Kharif 2017 to study the effect of nutrient levels and schedule of nutrient application on the yield and economics of upland rice intercropped in coconut. The experiment was conducted in RBD with four different nutrient levels and four different schedules of nutrient application. Nutrient levels significantly influenced the grain and straw yield, net returns and B: C ratio and the highest grain yield, straw yield, net returns and B: C ratio were recorded with the application of NPK @ 90:30:45 kg ha-1. Nutrient schedules also have significant effect on grain yield, net returns and B: C ratio. Among the schedule of nutrient application, N applied in three splits (15 days after sowing (DAS), active tillering and panicle initiation stage), P as basal and K in two equal splits (15 DAS and panicle initiation stage) along with foliar application of 0.2 per cent zinc sulphate and 0.04 per cent sodium borate recorded the highest grain yield, net returns and B:C ratio. Interaction between nutrient levels and schedule of nutrient application was also found significant. NPK @ 90:30:45 kg ha-1 , applied as N in three equal splits (15 DAS, active tillering and panicle initiation stage), P as basal and K in two equal splits (15 DAS and panicle initiation stage) along with foliar application of 0.2 per cent zinc sulphate and 0.04 per cent sodium borate at 45 DAS recorded higher grain yield, net returns and B:C ratio and can be recommended for upland rice raised as intercrop in coconut.

Agricultural Reviews, Nov 7, 2022

Carbon sequestration plays a significant part in alleviating climate change by changing over clim... more Carbon sequestration plays a significant part in alleviating climate change by changing over climatic carbon as plant biomass and soil organic carbon. Since trees can hold greater carbon in their biomass than other plant types, perennial plantations have a vital function in mitigating the advers ities in c limate. Coc onut is a perennial palm with a life time of around 50-60 years has the capability to store carbon for a long time, especially in the stem. Due to the increased availability of space and solar radiation reaching the understorey, the carbon sequestration capacity of coconut plantations can be considerably increased. As a result, intercropping or agroforestry in coconut lands is important not only for food and economic security but also for carbon sequestration. On an average carbon sequestration potential of coconut trees range between 37 kg tree-1 yr-1 (dwarf variety) up to 56 kg tree-1 yr-1 (tall variety). After 20 years of establishment, monoculture coconut land can be transformed into perennial mixed cropping or agroforestry system that can sequester more carbon.

Indian Journal of Weed science, 2023

Agricultural Reviews

Melochia corchorifolia L. commonly known as ‘Chocolate weed’ is an annual herbaceous troublesome ... more Melochia corchorifolia L. commonly known as ‘Chocolate weed’ is an annual herbaceous troublesome weed found in cultivated land across the world. ‘Eradication by Utilization’ could be employed as an effective means of managing Melochia corchorifolia. Plant extracts of Melochia corchorifolia can be utilized for the control of the storage pest, Callosobruchus maculatus. Active fraction of the plant extract along with neem oil and karanj oil could be used to prepare botanical pesticides. Several phytochemicals having pharmacological properties have been identified from the plant extracts of Melochia corchorifolia. Being a good source of minerals and nutrients, the fresh leaves are used as food and folk medicine in various parts of the world.

Indian Journal of Weed Science

Agricultural Reviews

Carbon sequestration plays a significant part in alleviating climate change by changing over clim... more Carbon sequestration plays a significant part in alleviating climate change by changing over climatic carbon as plant biomass and soil organic carbon. Since trees can hold greater carbon in their biomass than other plant types, perennial plantations have a vital function in mitigating the adversities in climate. Coconut is a perennial palm with a life time of around 50-60 years has the capability to store carbon for a long time, especially in the stem. Due to the increased availability of space and solar radiation reaching the understorey, the carbon sequestration capacity of coconut plantations can be considerably increased. As a result, intercropping or agroforestry in coconut lands is important not only for food and economic security but also for carbon sequestration. On an average carbon sequestration potential of coconut trees range between 37 kg tree-1 yr-1 (dwarf variety) up to 56 kg tree-1yr-1 (tall variety). After 20 years of establishment, monoculture coconut land can be t...

Agricultural Reviews

Millets are the traditional staple food of dry land regions and have the potential to contribute ... more Millets are the traditional staple food of dry land regions and have the potential to contribute substantially for food, fodder and the nutritional security. The millets are relatively poor competitors against weeds especially during the early growth stages due to their slow initial growth and wider spacing. Yield loss due to weeds in millets varies from 5 to 94 per cent depending on climatic, edaphic and biotic factors. Weeds compete with crops for nutrients, soil moisture, sunlight and space when they are limiting, resulting in reduction in yield, quality and increased cost of production. The objective of this paper is to review the research that have been conducted pertaining to various aspects of weed management in millets. The literature suggests that instead of relying on any single method of weed control, all the feasible methods are to be integrated for the effective and sustainable management of weeds in millets. Integrated weed management can effectively overcome the probl...

Agricultural Science Digest - A Research Journal

Background: Weeds are the major biological constraint in okra due to its slow initial growth and ... more Background: Weeds are the major biological constraint in okra due to its slow initial growth and wider row spacing. Due to severe crop weed competition, weeds removed considerable amount of nutrients from the soil. Competition exists between the crop and weed for nutrients results in nutrient deficiencies in crop. Hence the present experiment is formulated to assess the effect of stale seedbed, mulching and mechanical weeding on nutrient availability, nutrient uptake by crop and weed in okra. Methods: Experiment was conducted at Coconut Research Station, Balaramapuram, Thiruvananthapuram, Kerala during Rabi 2020-21. Design adopted for the study was RBD with two factors. The first factor was seedbed preparation (S) and the second factor was weed management (W). Stale seedbed (S1) and normal seedbed (S2) were the two different seedbed preparation methods and dried banana leaf mulch @10 t ha-1 alone (W1), dried banana leaf mulch @10 t ha-1 fb wheel hoe weeding at 30 and 45 DAS (W2), dr...

Journal of Crop and Weed, 2020

The site was located at 8°22'52" North latitude and 77°1' 47" East longitude and at an altitude o... more The site was located at 8°22'52" North latitude and 77°1' 47" East longitude and at an altitude of 9 m above mean sea level. A warm humid climate prevailed over the experimental site. The data on daily weather parameters like mean temperature, relative humidity (RH), rainfall and evaporation were noted from the Class B Agromet observatory attached to the site. The rainfall received during the crop season was 952.3 mm. The soil texture was sandy loam with acidic pH (4.6). The soil had medium organic carbon (0.79%), N (301.50 kg ha-1), P (21.10 kg ha-1) and low K (93.07 kg ha-1) status.

Journal of Applied and Natural Science, 2018

Micronutrients, though needed in smaller amounts, play a major role in the production and product... more Micronutrients, though needed in smaller amounts, play a major role in the production and productivity of rice. Zn is the fourth most deficient nutrient element in Indian soils and its deficiency causes severe yield reduction in rice. Application of Zn either as foliar spray or soil application caused significant improvement in growth and yield attributes and yield of rice. Similar to that of Zn, B nutrition also caused significant improvement in growth and yield attributes and yield of rice. The review elaborates the effect of Zn and B nutrition on the growth, physiological parameters, yield attributes, yield and quality of rice.

International Journal of Chemical Studies, 2021

A study was conducted to determine the soil quality and changes in the fertility status of soils ... more A study was conducted to determine the soil quality and changes in the fertility status of soils after 2018 flood in Agro-ecological unit (AEU) 9 in Pathanamthitta district of Kerala and GIS maps were generated. A survey was conducted in the study area and seventy five geo referenced soil samples were collected from flood affected panchayaths. The samples were analysed for pH, organic carbon, N, P, K, Ca, Mg, S and micronutrients and GIS based thematic maps were prepared. The results of the study revealed that pH of soil falls into very strongly acidic, strongly acidic and moderately acidic categories after flood. Organic carbon and available K were increased and available P slightly decreased after the floods and widespread deficiency of available nitrogen were observed. Calcium and magnesium status also low in post flood soils. Among the micronutrients boron was highly deficient. The results outline the need for regular liming to control soil acidity and to alleviate Ca deficiency. The soils should be supplemented with Mg and B in addition to recommended dose of N, P and K fertilizers. Soil quality index of the postflood soils of AEU 9 was calculated from eight parameters of minimum data set viz., organic carbon, bulk density, available K, available B, available S, sand percent and manganese. Majority of the soils had high soil quality index of more than 70.

Agricultural Reviews, May 4, 2022

Weeds are the major biological constraint in oilseed crops. Yield loss in oilseeds vary from 20 t... more Weeds are the major biological constraint in oilseed crops. Yield loss in oilseeds vary from 20 to 77 per cent, depending on the crop, intensity of weed infestation, duration of crop competition, soil and climatic factors. Weed interference, not only reduces the seed yield, but also reduces the oil yield and quality. Critical period of weed control in oilseeds are generally from 15 to 45 DAS. Weed removal during the critical period is essential to reduce the yield loss. Hike in wage rate and phytotoxicity of herbicides calls for an integrated approach for weed management in oilseeds. Instead of relying on a single method, a holistic approach which involves the adoption of cultural/mechanical/biological/chemical methods is essential to keep the weeds below the threshold level for higher yield, productivity and net returns in oilseed crops.

Journal of Crop and Weed, 2018

Bioassay tests were carried out at Department of Agronomy, College of Agriculture Vellayani durin... more Bioassay tests were carried out at Department of Agronomy, College of Agriculture Vellayani during 2014 and field experiments were carried out during kharif 2014 and rabi 2014-15 in farmers field at Kalliyoor Panchayat of Thiruvananthapuram district, Kerala. Response of three test crops, maize, cucumber and sunflower to penoxsulam + cyhalofop butyl revealed that maize was the most sensitive indicator plant and fresh shoot weight of maize was the most susceptible parameter to detect the phytotoxic residue of this herbicide in soil. Bioassay with maize plant in post experiment soil during both the seasons revealed that post emergence application of penoxsulam + cyhalofop even at a concentration of 135 g ha-1 did not cause any growth inhibition in fresh shoot and dry weight, shoot length and root length inferring that, the herbicide penoxsulam + cyhalofop butyl 6 % OD (oil dispersion) did not leave any phytotoxic residue in soil and is environmentally safe.

Research on Crops, 2015

The field experiments were conducted during kharif and rabi 2014 to study the efficacy of pre-mix... more The field experiments were conducted during kharif and rabi 2014 to study the efficacy of pre-mix herbicide mixture penoxsulam+cyhalofop butyl for weed control in direct seeded puddled rice. The experiment was laid out in randomized block design with eight treatments and three replications. The treatments comprised four different doses of penoxsulam+cyhalofop butyl 6% OD viz., 120, 125, 130 and 135 g a. i./ha, bispyribac sodium 10% SE 25 g a. i./ha, penoxsulam 24 SC 22.5 g a. i./ha, hand weeding twice and weedy check. On 30 days after sowing (DAS) weed flora comprised sedges (53.91%), broad leaf weeds (37.88%) and grasses (8. 2%) and on 60 DAS weed flora constituted sedges (53.15%), broad leaf weeds (BLW) (34.66%) and grasses (12.19%). The dominant weed species present in the experimental field were Schoenoplectus juncoides (Roxb.) Palla, Cyperus iria L. and Cyperus difformis L. among sedges; Isachne miliaceae Roth among grasses and Ludwigia perennis, Limnocharis flava (L.) Buch., Marsilea quadrifoliata L. and Bergia carpensis L. among broad leaf weeds. Pre-mix herbicide mixture, penoxsulam+cyhalofop butyl was found to be effective in reducing the density and dry weight of weeds at 30, 45 and 60 DAS. Among the doses, higher doses of penoxsulam+cyhalofop butyl (130 and 135 g a. i./ha) were found to be more effective in reducing the dry weight with a weed control efficiency of 97.34 and 98.31%, respectively. Higher growth and better expression of yield attributes were registered for these treatments. Adoption of weed control measures enhanced the grain yield from 4.26 to 8.46 t/ha. All the tested doses of penoxsulam+cyhalofop butyl recorded higher grain yield compared to hand weeding, penoxsulam and bispyribac sodium applied alone. Application of penoxsulam +cyhalofop butyl at its higher dose (135 g a. i./ha) recorded the highest grain yield which was on a par with its lower dose 130 g a. i./ha. The highest gross returns and B: C ratio were also recorded by these treatments. Bispyribac sodium was found to be less effective in reducing the density and dry weight of sedges resulting in lesser yield and B: C ratio compared to penoxsulam in the present study. Hand weeding recorded the lowest gross returns and B: C ratio among the weed control treatments. The study concludes that better broad spectrum control of weeds can be achieved by the post-emergence application of herbicide mixture penoxsulam+cyhalofop butyl on 15 DAS. The selection of herbicide and dose should depend on the target weed species in an area.

Madras agricultural journal, 2012

The Indian Journal of Agricultural Sciences, 2013

Journal of Crop and Weed, 2020

Field experiment was carried out to study the effect of stale seed bed and weed management practi... more Field experiment was carried out to study the effect of stale seed bed and weed management practices on nutrient uptake by weeds, nutrient uptake and green pod yield of bush type vegetable cowpea during Kharif season 2019 at Coconut Research Station, Balaramapuram. The experimental was conducted in randomized block design with two factors viz., factor A-seed bed preparation with two treatments and factor B-weed management practices with eight treatments in three replications. Stale seed bed recorded the lowest total weed dry weight, NPK uptake by weeds and the highest NPK uptake by crop and green pod yield. Among the weed management practices, dried banana leaf mulch @ 10 t ha-1 fb quizalofop-p-ethyl @ 50 g ha-1 on 25 DAS recorded the lowest total weed dry weight, NPK uptake by weeds and the highest total N and P uptake by crop and green pod yield (7589.0 kg ha-1). Pre emergence diclosulam @ 12.5 g ha-1 fb hand weeding at 25 DAS recorded the highest K uptake by crop. Interaction effect revealed that the stale seed bed + dried banana leaf mulch @ 10 t ha-1 fb quizalofop-p ethyl @ 50 g ha-1 on 25 DAS recorded the highest N and P uptake by crop, number of pods per plant, pod weight and green pod yield. The lowest weed dry weight and the lowest NPK uptake by weeds was registered in stale seed bed + pre emergence application of diclosulam @ 12.5 g ha-1 fb hand weeding at 25 DAS.

Journal of Applied and Natural Science, 2018

Field experiment was conducted at Coconut Research Balaramapuram, during Kharif 2017 to study the... more Field experiment was conducted at Coconut Research Balaramapuram, during Kharif 2017 to study the effect of nutrient levels and schedule of application on the quality parameters of upland rice intercropped in coconut. The experiment was conducted in randomized block design (RBD) with four different nutrient levels and four different schedules of nutrient application. Quality parameters like crude protein and starch content were significantly influenced by nutrient levels. The crude protein content was found to increase with increase in N level, however starch content was found to increase up to 70 kg N and 35 kg K ha-1 and after that a decline in trend was observed. The highest crude protein content (8.38 per cent) was recorded with highest nutrient level, NPK @ 120:30:60 kg ha-1. However, lower nutrient level, NPK @ 70:30:35 kg ha-1 recorded higher starch content (85.03 per cent). Among the schedule of nutrient application, N applied in three equal splits (15 days after sowing (...