Md. Jewel Alam*
Department of Entomology, Bangladesh Agricultural University, Mymensingh, Bangladesh
Most. Khairun Nahar
Department of Agronomy, Bangladesh Agricultural University, Mymensingh, Bangladesh
Sowing dates, Rhopalosiphum maidis, Maize infestation, Morpho-physiological characters, Yield attributes.
Entomology Field Laboratory under Department of Entomology, Bangladesh Agricultural University (BAU), Mymensingh
Pest Management
2.1 Location of experimental site and experimental duration The research experiment was conducted on maize at Entomology Field Laboratory under Department of Entomology, Bangladesh Agricultural University (BAU), Mymensingh during Rabi season of 2016-17 in order to know the best sowing date of maize production instead of low aphid infestation where, maximum yield will be produced. The research site was situated at 24.75 N latitude and 0.50 E longitudes at an average altitude of 18m above the mean sea level. The site of experiment belongs to the Sonatola series of the dark grey floodplain soil type under Old Brahmaputra Floodplain Agro-Ecological Zone (AEZ-9) (Alam et al., 2019a, b; 2020a, b). 2.2 Soil properties Initial soil samples were collected randomly from each replication of respective experimental field using shovel from 0 to 15cm before application of FYM and chemical fertilizers. Then the collected samples were air dried, grounded and made fine. Finally, analysis was done through using Soil Kit-Box method. The field was a medium high land with well drained silty-loam texture. 2.3 Weather data The condition of climate in Bangladesh was moderately cold and high humid with frequent wind during maize cultivation. Monthly mean weather data was recorded during the crop growing season from July 2016 to June 2017. The mean maximum temperature 300C and minimum temperature 180C were recorded. Maximum temperature ranged from 25.50C to 300C. The minimum temperature ranged from 180C to 23.40C. Similarly, relative humidity ranged from 75% to 87%. The highest rainfall (522.7mm) and the lowest rainfall (0.00mm) were recorded. The maximum sunshine of 204.8hrs and the minimum sunshine of 84.70hrs were recorded in the time of crop season. The detail information of weather data were depicted in Table 2 (Alam et al., 2020a). 2.4 Experimental design, materials and treatments details The experiment was laid out in randomized complete block design (RCBD) having three replications. Total number of experimental plots was 27. Maize var. BARI Hybrid Butta-09 variety was used as experimental crop. The experiment consisted of nine (09) dates of sowing were scheduled as treatments viz. 3rd & 4th week of October, 1st, 2nd, 3rd & 4th week of November and 1st, 2nd & 3rd week of December of Rabi season, 2016-17. The details of nine sowing dates are depicted in the Table 3. 2.5 Plot size, design and crop sowing The crop was sown according to nine mentioned sowing dates as treatments wise in the experimental fields with a plot size of 10m2 (4m×2.5m), spacing of 60×30cm between row to row and plant to plant, respectively, and the distance was 70cm between the two plots. Five (05) plants were taken from each plot as sample. Seed sowing was done using manual practice after final land preparation. Seeds were treated with Bavistin@2g/kg of seeds one day prior of sowing. Before sowing, seeds were soaked in water over night for easy germinating in every mentioned sowing time. 2.6 Crop husbandry The land was ploughed through six (06) cross ploughing using mini power tiller to bring the soil under good tilth 15 days prior of seed sowing. The FYM@ 8kg/plot area (10m2) was applied in all experimental plots and it was uniformly incorporated into the soil during the first land preparation. Besides, the others fertilizers were used properly. Before final ploughing, all fertilizers were applied during land preparation except urea and Muriate of Potash (MOP). One-fourth of urea and MOP were applied at the time of final land preparation. The nitrogen, phosphorus, potassium, sulphur, mangnishium, zinc and boron fertilizers were applied in form of urea, triple super phosphate, muriate of potash, gypsum, magnesium sulphate, zinc sulphate and boric acid at the rate of 250, 80, 120, 45, 8, 3 and 2.4 kg ha-1, respectively (FRG, 2012, Alam, et al., 2019b, 2020a, b). The seed rate of maize was 20kg per hectare. The seed of maize (BARI Hybride Butta-09) was sown according to experimental scheduled sowing dates in line with raise. Remaining urea and MOP were applied three equal installments at pre-vegetative stage, full vegetative stage and early corn formation stage. Firsthand weeding and earthing up were done at 45 days after sowing (DAS). After that secondhand weeding were performed at 75DAS. Irrigation and other intercultural operation were done properly as and when necessary for better growth and development of maize. Harvesting was carried out in 145 days after respective tested sowing manually.
Sustainability in Food and Agriculture (SFNA) 1(2) (2020) 87-94
Journal