F. Alam
Soil Science Division, Bangladesh Agricultural Research Institute, Joydebpur, Gazipur, Bangladesh
M. I. A. Howlader
Soil Science Division, Bangladesh Agricultural Research Institute, Joydebpur, Gazipur, Bangladesh.
M. A. H. Bhuiyan
Soil Science Division, Bangladesh Agricultural Research Institute, Joydebpur, Gazipur, Bangladesh.
Bio-fertilizer, Vermicompost, Groundnut, Nutrient, Chemical fertilizer
RARS, Rahmatpur, southwestern region of Barisal
Crop-Soil-Water Management
Bio fertilizer, Gardenpea, Vermicompost and vermiculture
A field experiment was carried out at RARS, Rahmatpur, southwestern region of Barisal (22.42o N latitude, 90.23o E longitude and above 4 m elevation from sea level) belongs to the Barisal series of non–calcareous Grey Floodplain Soils (AEZ-13) on 02 November 2015 and 30 November 2016 during rabi season. The experiment was laid out in Randomized Complete Block Design (RCBD) with four replications. There were nine treatments viz. T1: Control (non-inoculated and non-fertilized), T2: Vermicompost (VC) @ 2.5 t ha-1, T3: VC @ 5 t ha-1, T4: VC @ 2.5 t ha-1 + IPNS based NPKSZnB, T5: VC @ 5 t ha-1 + IPNS based NPKSZnB, T6: VC @ 2.5 t ha-1 + Bradyrhizobium inoculant + IPNS based PKSZnB, T7: VC @ 5 t ha-1 + Bradyrhizobium inoculant + IPNS based PKSZnB, T8: 100% NPKSZnB, T9: Bradyrhizobium inoculant + 100% PKSZnB. The tested crop was groundnut (cv. BARI Chinabadam-8). Peat based rhizobial inoculum (Bradyrhizobium strain BARI RAh-892) was used containing 108 cells g-1 inoculum was used at the rate of 1.5 kg ha-1. Groundnut seeds were mixed thoroughly with the inoculum before sowing. The unit plots measured 2 m × 3 m. Seeds were used at the rate of 75 kg ha-1. Nitrogen, phosphorus, potassium, sulphur, zinc and boron were used in the form of urea, TSP, MoP, gypsum, zinc sulphate and boric acid, respectively. All P, K, S, Zn, B, vermicompost and 1/3rd urea-N were applied at the time of final land preparation and the remaining 2/3rd urea-N was applied in two equal installments at 30 and 50 days of sowing. All the intercultural operations such as irrigation, weeding, insect control etc. were done as and when necessary. Vermicompost was prepared in net house of Soil Science Division and used in the plot mixed with soil. Nodules were collected by carefully uprooting five sample plants selected randomly from each unit plot at the 50 percent flowering stage. Nodules were separated from the roots, counted and then oven-dried and weighed. Data on yield and yield components were recorded at maturity. The crop was harvested on 08 May 2016 and 30 May 2017. The initial soil samples at a depth of 0-15 cm from the experimental fields were collected and analyzed following standard methods. The vermicompost used in this experiment were also analyzed. Data on yield and yield contributing characters were recorded and statistical analyses were conducted using standard statistical procedures (Gomez and Gomez 1984) implemented in Statistix 10. The data were examined by analysis of variance (ANOVA). Differences between the treatments were determined by ANOVA, and Fisher’s protected least significant difference (LSD) was calculated at the 0.05 probability level for treatment mean comparisons.
Methods of chemical analysis:
Soil pH was measured by a combined glass calomel electrode (Jackson, 1958). Organic carbon was determined by wet oxidation method (Walkley and Black). Total N was determined by modified Kjeldahl method. Calcium, K and Mg were determined by NH4OAc extraction method. Copper, Fe, Mn and Zn were determined by DTPA extraction followed by AAS reading. Boron was determined by CaCl2 extraction method. Phosphorus was determined by Bray and Kurtz method (Acid soils) and Modified Olsen method (Neutral + Calcareous soils). Sulphur was determined by CaH4(PO4)2.H2O extraction followed by turbidimetric turbidity method with BaCl2..
Annual Research Report 2016-2017, Soil Science Division, Bangladesh Agricultural Research Institute, Joydebpur, Gazipur, Bangladesh.
Report/Proceedings