A field experiment was carried out in the micronutrient experimental field, Soil Science Division of the Bangladesh Agricultural Research Institute (BARI), Joydebpur, Gazipur on 09 December, 2019 with a view of study the effect of seed priming on yield and nutrient uptake of. cauliflower. The experiment was laid out in a randomized block design with three replications having plot size 3m×3m. Six different treatments viz. T1: Control (without priming), T2: Hydropriming (soaked with distilled water), T3: Seed soaked with 0.5% zinc, T4: Seed soaked with 0.01% boron, T5: Seed soaked with 0.05% zinc and 0.01% boron and T6: Seed soaked with sand matrix.
The tested variety was snow white. Healthy and equal sized thirty five days age seedlings of cauliflowers were transplanted in line with 50 cm line to line and 50 cm plant to plant spacing. N, P, K, S were supplied from urea, TSP, MoP and gypsum respectively. All PKS and 1/3 of N were supplied at the time of final land preparation. The remaining two third of N were applied as top dress at 30 and 60 days after transplanting. Irrigation was applied in three times. Other intercultural operations were done as and when necessary. The source of micro nutrient for boron and zinc were boric acid and zinc sulphate, respectively. The cauliflower was harvested on 18 to 27 February, 2020. Data on yield and yield contributing characters were recorded and analyzed statistically using Statistics-10 software. Significant differences were tested among treatments by one-way ANOVA and via Tukey HSD tests for multiple comparisons at a 5% significance level. Plants samples were collected from each plot for laboratory analysis.
Methods of chemical analysis of soil:
Initial soil samples collected from 0-15 cm depth prior to fertilizer application, were analyzed for all important soil parameters using standard procedures. Standard methods were used in these determinations. Soil pH was measured by a combined glass calomel electrode (Jackson, 1958). Organic carbon was determined by the wet oxidation method (Walkley and Black). Total N was determined by a modified Kjeldahl method. Calcium (Ca), magnesium (Mg) and K were determined by NH4OAc extractable method, copper (Cu), iron (Fe), manganese (Mn) and zinc (Zn) were determined by DTPA extraction followed by AAS reading. Boron (B) was determined by CaCl2 extraction method. Available P was determined by the Bray and Kurtz method while S was determined using the turbidimetric method with BaCl2.
Digestion and analytical procedure:
One gram of each sample was weighed into 50-ml beakers, followed by the addition of 10 ml mixture of analytical grade acids HNO3: HCIO4 in the ratio 5:1, and left overnight for complete contact of material. Next day, the digestion was performed at a temperature of about 190ºC for 1.5 h. After cooling, the samples were transferred into 100 ml volumetric flask and solution was made up to a final volume raised up to the mark with distilled water. Zinc was determined by DTPA extraction followed by AAS reading. Boron (B) was determined by CaCl2 extraction method. Analysis of each sample was carried out three times to obtain representative results and the data reported in µg g-1 (on a dry matter basis).
Seed priming techniques: Cauliflower seeds was soaked in aerated solutions of 0.5% Zn, 0.01% B, in sand matrix and in various combinations of these for 8?h. All solutions were prepared in distilled water and seed to solution ratio was kept 1:5 (w/v i.e. 1?kg seed in 5 liters of solution) for seed priming. Aeration was provided throughout the priming to avoid anaerobic condition development. After soaking, seeds were rinsed thoroughly three times with distilled water and re-dried under shade to their original weight. Both treated and untreated seeds were sown in the well-prepared field.