M. Rahman
Pulses Research Centre, BARI, Ishurdi, Pubna, Bangladesh
M.A.H. Bhuyin
Pulses Research Centre, BARI, Ishurdi, Pubna, Bangladesh
M.E. Ali
Pulses Research Centre, BARI, Ishurdi, Pubna, Bangladesh
M.A. Hossain
Pulses Research Centre, BARI, Ishurdi, Pubna, Bangladesh
Pulse, Lentil, Grain yield, Mungbean, Soil salinity
Soil Science Division, BARI, Joydebpur, Gazipur, Bangladesh
Crop-Soil-Water Management
Mungbean, Soil salinity
The experiment was carried out during rabi season from March, 2017 to May, 2017 in the net house of Soil Science Division, BARI, Joydebpur, Gazipur (230 59'378'' N latitude, 900 24'886'' E longitude and 8.4 m elevation). Seeds of mungbean (BARI Mung-6) were collected from Pulses Research Centre, BARI, Gazipur. The silted (sandy clay loam) soils were collected from the bank of Turag river at Kodda, Gazipur mixed with cowdung at 5:1 ratio and was used as the potting media. Each pot (28 cm in diameter and 23 cm in height) was filled with approximately 8-kg soil leaving upper 3 inches of pot was vacant to facilitate watering. The pH of cowdung was 6.7 and the nutrient contents were: organic matter 14.1%, N 0.8%, P 1.26%, K 0.88%, Ca 1.55%, Mg 0.82%, S 0.62%, Fe 0.25% and Mn 0.112%. The physical and chemical properties of the soil are presented in Table 1. The soil contained 12 AM (100-1 g soil) spores of indigenous mixed AM fungal species and the experiment was conducted under u nsterilized soil condition. Soil pH was measured by a combined glass calomel electrode (Jackson, 1958). Organic carbon was determined by Wet Oxidation Method (Walkley and Black, 1934). Total N was determined by modified Kjeldahl method (Jackson, 1962). Calcium, K and Mg were determined by NH4OAc extraction method (Black, 1965). 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 Modified Olsen method (Neutral + Calcareous soils) according to Olsen et al. (1954). Sulphur was determined by CaH4(PO4)2.H2O extraction followed by turbidimetric turbidity method with BaCl2. Fertilizer application: Chemical fertilizers @ 22.56 kg N ha-1 from urea, 24.45 kg P ha-1 from TSP, 34.27 kg K ha-1 from MoP, 7.95 kg S ha-1 from gypsum, 2.23 kg Zn ha-1 from ZnSO4, 0.81 kg B ha-1 from Boric acid and 0.34 kg Mo ha-1 from Na2MoO4.2H2O were applied (BARC, 2012). Half of urea-N and all other fertilizers were applied as basal during final land preparation and remaining half amount of urea-N were applied after 10 days after sowing. Preparation of salinity solution and mycorrhizal inoculum: Different concentrations of salinity were prepared according to New South Walles (NSW) Department of Primary Industries 2005, Australia and applied three times during the experimentation period. First before sowing of mungbean seed, next after 25 DAS and then after 35 DAS. The arbuscular mycorrhizal inoculum was prepared from the roots and rhizosphere soils of Sorghum. Mycorrhizal species was originally isolated from different AEZ region, using the wet sieving and decanting method. The spores were left to multiply for 6 months on sorghum plants using unsterilized soil, collected from the same site, in the net house of Soil Science Division, BARI. Plants were irrigated with tap water as needed. A mixture of infected sorghum root and soil which contained spores was used as mycorrhizal inoculum. The soil based AM fungal inoculum containing 150 g of rhizosphere soil (approximate 275 ± 20 spores/100 g soil) and infected sorghum root fragments with a minimum infection level was inoculated to each mycorrhizal pot. The mycorrhizal inoculum were first placed in each pot at 3-5 cm depth and was covered with a thin soil layer of 1 cm immediately prior to the seed sowing of mungbean to facilitate fungal colonization of plant roots. The germination test was carried out according to ISTA rules (ISTA, 1976). For each treatment, 25 seeds were put into Petri dishes. The Petri dishes were put on a laboratory table at room temperature (25 ± 2oC). After 3 days, normal, abnormal and diseased seeds were counted. Germination of mungbean seed in the laboratory table was 84%. Ten seeds were sown in each pot. After 4, 6, 8 and 10 days germinated seeds were observed and counted. Germination percentage was calculated by the following formula: Germination (%) = (Number of germinated seeds in each pot) / (Total number of seeds sown in each pot) x 100. Assessment of root colonization infection: The percentage of AM infection was estimated by root slide technique (Read et al., 1976). One hundred root segments were examined for each sample. The stained root pieces were mounted in acidic glycerol on slides and the cover slip was placed and slightly pressed. The roots were observed under microscope. A root segment was considered as positively infected, if it showed mycelium, vesicles and arbuscules or any other combination of these structural characteristics of AM infection. The presence or absence of infection in the root pieces was recorded and the percent infection was calculated as follows: % root colonization = (Number of AM positive segments)/(Total number of segments scored) x 100. Statistical analysis: Data were statistically analyzed using Analysis of Variance (ANOVA) following CropStat package while the all pair comparisons were done by Statistix 10.
Annual Research Report-2016-2017, Pulses Research Centre, BARI, Ishurdi, Pubna, Bangladesh
Report/Proceedings