Nutrient Uptake of Maize and Its Associated Weeds As Influenced by Sequential Application of Herbicides

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1 Available online at wwwijpabcom DOI: ISSN: Int J Pure App Biosci 5 (): 9-5 (2) Research Article Nutrient Uptake of Maize and Its Associated Weeds As Influenced by Sequential Application of Herbicides Shaik Nazreen *, D Subramanyam, N Sunitha 2 and V Umamahesh 3 Department of Agronomy, SV Agricultural College, Tirupati, ANGRAU, Department of Agronomy, Regional Agricultural Research Station, Tirupati, ANGRAU 3 Department of Crop Physiology, SV Agricultural College, Tirupati, ANGRAU, 5 52 *Corresponding Author nazreennaz5@gmailcom Received: 22 Revised: 2 Accepted: 22 ABSTRACT An experiment was carried out during the kharif season of 2 at Tiruapti with weed management practices to study the nutrient depletion patterns by kharif maize ( Zea mays L) and associated weeds Amongst the weed management practices, nutrient depletion by weeds was minimum under hand weeding and maximum (322 kg N, 3 kg P 2 O 5 and kg K 2 O/ha) in weedy condition, whereas total nutrient uptake by kharif maize was maximum ( kg N, 35 kg, P 2 O 5 and 9 kg K 2 O/ha) under the treatment pre-emergence application of alachlor g/ha fb post-emergence 5 g/ha + tembotrione g/ha followed by hand-weeding (53 kg N, 22 kg P 2 O 5 and 82 kg, K 2 O/ha) The nutrient uptake by crop in weedy condition was least Chemical weeding checked nutrient drain by weeds significantly compared with weedy check The reduction in yield due to weeds in unweeded check was 532 per cent Key words: Maize, Nutrient uptake, Pre-emergence, Post-emergence, Weed management practices INTRODUCTION Maize (Zea mays L) is the most widely cultivated cereal crop after rice and wheat in India Maize is predominantly a rainy season (Kharif) crop that constitutes 85% of total maize area in the country The area under maize cultivation is 98 m ha in 2-5 with productivity, 23 t/ha (wwwindiastatcom) Maize is sensitive to weeds which occur at 25 to 3 days of crop and severe competition for valuable resources like soil, water, nutrients, solar radiation, thus lowering the productivity of maize Nutrients are inputs and their drain through weeds can be checked by weed management approach Weed management in maize needs concentrated efforts to provide weed free environment to the crop At present pre-emergence herbicides especially Atrazine used continuously for control of weeds in maize Cite this article: Nazreen, S, Subramanyam, D, Sunitha, N and Umamahesh,V, Nutrient Uptake of Maize and Its Associated Weeds As Influenced by Sequential Application Of Herbicides, Int J Pure App Biosci 5(): 9-5 (2) doi: Copyright Nov-Dec, 2; IJPAB 9

2 Thus, farmers are in need of post-emergence herbicides for effective control of weeds which occur at 25 to 3 days of crop The development of wide spectrum herbicide in the recent past has opened up excellent opportunities for chemical weed control A very few studies have been carried out to quantify the nutrient losses by weeds in winter maize Keeping this in view, present investigation was carried out to study the effect of pre, post, sequential and combination of pre- and post-emergence herbicides on nutrient losses in kharif maize MATERIALS AND METHODS A field experiment was conducted on maize during kharif, 2 at Wetland Farm of SV Agricultural College, Tirupati, Andhra Pradesh The experimental field was heavily infested with mixed flora of sedge, grasses and broad-leaved weeds, viz Digitaria sanguinalis L, Cyperus rotundus L, Boerhavia erecta L, Borreria hispida L, Trichodesma indicum L, Phyllanthus niruri L, Digera arvensis L, Commelina benghalensis L, Cleome viscose L, Euphorbia hirta L and Celosia argentea L The soil of the experimental field was sandy loam in texture, neutral in reaction (ph ), low in organic carbon (25 %), available N (2 kg) but medium in available phosphorus (255 kg) and available potassium (285 kg/ha) Ten treatments, viz pre-emergence application of alachlor g/ha (W ), post-emergence 5 g/ha (W 2 ), post-emergence application of tembotrione g/ha (W 3 ), post-emergence g/ha + tembotrione g/ha (W ), pre-emergence application of alachlor g/ha + postemergence 5 g/ha (W 5 ), pre-emergence application of alachlor g/ha + post-emergence application of tembotrione g/ha (W ), preemergence application of alachlor g/ha fb post-emergence application of halosulfuronmethyl 5 g/ha + tembotrione g/ha (W ), pre-emergence application of atrazine g/ha + post-emergence application of 2,-D sodium salt 8 g/ha (W 8 ), two hand weedings at 2 and DAS (W 9 ) and unweeded control (W ) These treatments were laid out in randomized block design at 5 % level of significance with three replications Recommended dose of 2 kg N, kg P 2 O 5 and 5 kg K 2 O/ha was applied to the crop Alachlor and atrazine as pre-emergence, 2,-D sodium salt, halosulfuron-methyl and tembotrione as post-emergence were applied as per treatment Herbicides were applied by using knap sack sprayer with flat fan nozzle Weed free treatment was achieved by repeated hand weedings Randomly five plants were selected from each plot and biometric observations of crop and weed parameters were recorded at periodic intervals Weed density and dry weight were recorded with a quadrate of 25 m 2 Nutrients were estimated using the standard procedures ie Micro kjeldhal method for Nitrogen, Vando molybdo phosphoric yellow colour method for Phosphorus and Flame photometer method for estimation of Potassium RESULTS AND DISCUSSIONS Nutrient uptake by crop All the weed management practices recorded significant increase in N, P and K uptake by crop (Table ) The highest nutrient uptake was obtained with pre-emergence application of alachlor g/ha fb post-emergence 5 g/ha + tembotrione g/ha, followed by with two hand weedings at 2 and DAS (Fig ) This might be due to higher crop dry matter accumulation and higher nutrient uptake in corresponding treatments because of reduced competition for nutrient uptake The nutrient uptake by crop and associated weeds follow an inverse relationship grown in a community These results are in accordance with the findings of Umesha et al 9 The lowest nutrient uptake ie nitrogen, phosphorus and potassium by crop was recorded with unweeded check due to poor dry matter production of crop and reduced nutrient uptake as a result of heavy weed competition These results are in conformity with the findings of Sinha et al Copyright Nov-Dec, 2; IJPAB 9

3 Table : Effect of sequential application of pre- and post-emergence herbicides on nutrient uptake of maize and its associated weeds Treatment Dose (g/ha) Time of application Dry matter production Nutrient uptake by crop Alachlor DAS Halosulfuron-methyl 5 2 DAS Tembotrione 2 DAS Halosulfuron-methyl + tembotrione (Tank mix) halosulfuron-methyl tembotrione halosulfuron-methyl+ tembotrione (Tank mix) Atrazine fb 2,-D Sodium salt 5+ 2 DAS DAS DAS Two hand weedings - +2 DAS DAS and DAS Dry weight of weeds (g/m 2 ) (8) (52) 3295 (55) Nutrient uptake by weeds N P K N P K Unweeded check CD(P=5) Figures in parenthesis indicates square root transformed ( X 5 3 ) values 8 (5) 3228 (53) (85) 8 (38) 58 (8) 8 (352) 2355 (535) Grain yield Net returns ( /ha) Benefitcost ratio Nitrogen Phosphorus kg ha - Treatments Fig : Uptake of nitrogen, phosphorus and potassium by maize as influenced by different weed management practices Nutrient uptake by weeds Uptake of N, P and K by weeds followed the trend of weed biomass Lower uptake of nitrogen, phosphorus and potassium by weeds at harvest was recorded with two hand weedings at 2 and DAS (Fig 2) due to effective control of all the categories of weeds, which inturn reduced the accumulation of dry matter in weeds Pre-emergence application of alachlor fb post-emergence application of halosulfuron-methyl + tembotrione was very effective in controlling all the categories of weeds during the entire crop growth period leading to reduced weed dry matter production These results are in accordance with the findings of Sanjay et at and Yakadri et al Heavy weed infestation in unweeded check resulted in increased uptake of nitrogen, phosphorus and potassium by weeds was 322, 3 and kg/ha, respectively Copyright Nov-Dec, 2; IJPAB 98

4 Nitrogen Phosphorus kg ha - Fig 2: Uptake of nitrogen, phosphorus and potassium by weeds in maize as influenced by sequential application of herbicides It was concluded that all weed management practices were equally effective in controlling weeds and improving nutrient availability to maize crop Pre-emergence application of alachlor g/ha fb post-emergence 5 g/ha + tembotrione g/ha recorded maximum crop dry matter production and grain yield followed by two hand weedings Lower weed dry matter was achieved with hand weeding twice at 2 and DAS Because of higher cost of herbicides even though pre-emergence application of alachlor g/ha fb postemergence 5 g/ha + tembotrione g/ha recorded maximum net returns, pre-emergence application of atrazine g/ha fb postemergence application of 2,-D Sodium salt 8 g/ha obtained highest benefit-cost ratio SUMMARY A field experiment was conducted to study the nutrient uptake of maize and its associated weeds as influenced by sequential application of herbicides during kharif 2 at Tiruapti, Andhra Pradesh The highest total uptake of N ( kg), P (35 kg) and K (9 kg/ha) by crop was recorded with pre-emergence application of alachlor g/ha fb postemergence 5 g/ha + tembotrione g/ha (Tank mix), while lowest uptake of total N (83 kg), P ( kg) and K ( kg/ha) by weeds was recorded under two hand weedings The Treatments nutrient uptake by weeds in unweed check was 322 kg N, 3 kg P 2 O 5 and kg/ha of K 2 O Weed biomass was reduced significantly with two hand weedings at 2 and DAS It was concluded that the treatment with pre-emergence application of alachlor g/ha fb post-emergence application of halosulfuron-methyl 5 g/ha + tembotrione g/ha can keep the weed density and dry weight below the economic threshold level and increase the nutrient availability and productivity of maize under irrigated conditions REFERENCES Alok Malviya, Nupur Malviya, Bhuwan Singh and Ashok Singh, K Integrated weed management in maize (Zea mays) under rainfed conditions Indian Journal of Dryland Agricultural Research and Development 2(): -3 (22) 2 Birendra Kumar, Ranvir Kumar, Suman Kalyani and Mizzanul Haque Integrated weed management studies on weed flora and yield in kharif maize Trends in Biosciences (2): - (23) 3 Kamaiah, I, Aravinda Kumar, BN, Geeta, GS and Ramesh Babu Effect of tank mixture herbicides on phytotoxicity, soil dehydrogenase activity and nutrient uptake by weeds in maize (Zea mays L) Trends in Biosciences (): (2) Copyright Nov-Dec, 2; IJPAB 99

5 Mahadi, MA Growth, nutrient uptake and mays L) and weeds as influenced by yield of maize (Zea mays L) as influenced integrated weed management Indian by weed control and poultry Journal of Agronomy 5(): 33-3 manureinternational Journal of Science (25) and Nature 5(): 9-2 (2) 8 Sonawane, RK, Dandge, MS, Kamble, 5 ParamjeetKour, Anil Kumar, Sharma, AS and Shingrup, PV Effect of BC, RanjeetKour and Neetu herbicides on nutrient uptake and yield of SharmaNutrient uptake as influenced by kharif maize (Zea mays L) Bioinfolet weed management in winter maize + (A): 3-38 (2) potato intercropping system Indian 9 Umesha, C, Sridhara, S and Aswini Journal of Weed Science (): 33-3 Effect of pre and post emergent herbicides (2) on growth, yield parameters and weed Sanjey, DK, Shrivastava, GK, Singh, control efficiency in maize (Zea mays L) AP and Kolhe SS Weed population, Trends in Biosciences 8(): 28-2 nitrogen removal by weeds and crop yield (25) under maize+blackgram intercropping Yakadri, M, Leela Rani, P, Ram Prakash, system in Chhattisgarh plainsindian T, Madhavi, M and Mahesh, N Weed Journal of Weed Science 3(3&): 23- management in zero till-maizeindian 2 (2) Journal of Weed Science (3): 2-25 Sinha, SP, Prasad, SM and Singh, SJ (25) Nutrient utilization by winter maize (Zea Copyright Nov-Dec, 2; IJPAB 5