The quality and efficacy of vermicompost are greatly influenced by the respective feeding materials as well as earthworm species used in vermicomposting. Consequently, the variable role of applied ...vermicompost is reflected in crop production. With a view to observe the efficacy of vermicompost produced from various sources in supplementing zinc and boron requirement for quality production of cabbage, a field study was conducted in Floodplain soil of Bangladesh. Six treatment combinations comprising of vermicompost from different sources, and different levels of zinc and boron from mineral fertilizers were tested in the study. The vermicompost used in different treatments were produced from different combinations of feeding materials (cowdung and poultry litter) and earthworm species (Eisenia fetida and Eudrilus eugeniae). A control treatment having no supplement of Zn and B was tested in the study. Higher measurements were recorded for most of the parameters studied, i.e., head diameter, marketable yield and total yield in the vermicompost treated plots than the solely mineral fertilizer treated plot. Except for P, the highest uptake of each of the elements by cabbage was observed due to the application of T3 treatment (VC-ECD @2.0 t ha-1 + 1.5 kg Zn ha-1 + 1.0 kg B ha-1). The findings of this research work indicate the additional benefit of using vermicompost over the mineral fertilizer in supplying zinc and boron for better production of cabbage.
A study was conducted to evaluate different doses of Zn and B along with their application schedule for the component crops in potato-rice-rice pattern in floodplain soil. The experimental layout was ...Randomized Complete Block Design with 3 replications. As treatment, zinc and boron were applied to the component crops of the pattern in different distributions so that their direct, residual and cumulative effects could be estimated. Other nutrients i.e., N, P, K and S were used equally at recommended rates for all plots. In such a 3-crop pattern, application of 4.0 kg Zn ha
−1
and 1.5 kg B ha
−1
at a time to the first crop or 2.0 kg Zn ha
−1
to each of the first two crops along with 1.5 kg B ha
−1
to the first crop was found sufficient to achieve satisfactory yield, system productivity, nutrient uptake by crops, and protein and Zn concentrations of crop produce. Zinc and boron containing fertilizers need not to apply in each of the component crops of a cropping pattern potato-rice-rice in floodplain soil. Each fourth crop is essential to be fertilized with 4.0 kg Zn ha
−1
and 1.5 kg B ha
−1
.
A study was conducted to find out suitable earthworm species as well as respective feeding materials in the way of producing quality vermicompost. Two earthworm species, i.e.,
Eisenia fetida
and
...Eudrilus eugeniae
were used to produce vermicompost from four selected combinations of feeding materials. The study was carried out in the vermicompost shed of the Department of Soil Science in Sylhet Agricultural University, Bangladesh, using completely randomized design. Earthworm species
E. fetida
has performed better than
E. eugeniae
in terms of the amount of vermicompost produced. On the other hand, using sole cow dung as feeding material produced the highest amount of vermicompost and induced for the highest increase in earthworm number comparing with the other feeding materials used. Cow dung as feeding materials and the interaction of
E. fetida
and cow dung was suitable for the highest earthworm biomass. There was an indication of vermiremoval of cadmium and lead from the feeding materials while vermicomposting. The earthworm species
E. fetida
was found to be more efficient in removing cadmium and lead from contaminated feeding materials. Cow dung containing feeding mixtures has resulted higher content of K, S, and B in vermicompost than the others. Considering all above aspects, it can be said that vermicompost produced from cow dung using
E. fetida
is a suitable option for higher production of quality vermicompost.
Different micronutrients have variable residual effects in the soil. Again, crops have variability in their response to applied micronutrient. An experiment was conducted in floodplain soil of ...Bangladesh using cauliflower, maize, and rice in a pattern to explore differential effects of micronutrients on crops. Seven treatments following additive element trial technique including a control were used in the study. Micronutrients were applied @ 3 kg Zn, 2 kg B, 2 kg Cu, 3 kg Mn, 5 kg Fe and 1 kg Mo per hectare. Cauliflower as the first crop of the pattern responded to direct application of both zinc and boron whereas significant residual effects of these elements were observed in the second crop (maize). In rice as the third crop, no significant residual effects were estimated. In floodplain soil, zinc and boron fertilizers are needed to apply in each third crop of a pattern where the second crop is nutrient exhaustive like maize.
Application of vermicompost is considered to be a good option to safe supply of micronutrients for crop production. Again, the quality of vermicompost varied with the earthworm species and their ...feeding materials used. A study was conducted to find out the variable roles of vermicomposts produced from various sources to meet the Zn and B requirement of cauliflower grown on a nutrient-deficient light-textured soil. Six treatment combinations including one control treatment and one treatment having 100% chemical sources of Zn–B (3 kg Zn ha
−1
+ 2 kg B ha
−1
) were tested. The other treatments comprises with four different types of vermicomposts @2.0 t ha
−1
from various sources along with Zn @1.5 kg ha
−1
and B@1.0 kg ha
−1
for each of the treatments. The vermicomposts used in different treatments were produced from
Eisenia fetida
-cow dung,
Eudrilus eugeniae
-cow dung,
E. fetida
-cow dung + poultry litter and
E. eugeniae
-cow dung + poultry litter combination. The treatment containing 3 kg Zn ha
−1
and 2 kg B ha
−1
from chemical fertilizers performed better than the control treatment. There was huge incidence (59.17%) of hollow heart disease in control treatment, but very little evidence (0.83–4.17%) of such incidence was recorded in other treatments. Again, the vermicompost containing treatments played superior role in supplying Zn–B to cauliflower than the sole chemical Zn–B-containing treatment. The vermicompost produced from
Eisenia fetida
-cow dung combination performed better than the other vermicomposts and the highest marketable curd yield (46.37 t ha
−1
), and total yield (67.09 t ha
−1
) was obtained using this treatment. In case of only curd production, the role of different vermicomposts was found similar.
An experiment was replicated simultaneously at two sites of floodplain soils of Bangladesh to find out the optimum application rate of zinc and boron fertilizers for crops under ...cauliflower-maize-transplant aus rice pattern. Randomized complete block design with three replications was used in the experimentation. The first crop of the pattern received four zinc levels (0, 2.0, 4.0, and 6.0 kg ha
−1
), and three boron levels (0, 1.5, and 3.0 kg ha
−1
). In second crop, two additional treatments receiving 2.0 kg Zn ha
−1
and 2.0 kg Zn ha
−1
+ 1.5 B ha
−1
were added; in the third crop, another four treatments were added by further application of 2 kg Zn ha
−1
in each. Other nutrients viz. N, P, K, and S were used equally at recommended rates for all plots. In such a 3-crop pattern, application of 4.0 kg Zn ha
−1
and 1.5 kg B ha
−1
at a time to the first crop or 2.0 kg Zn ha
−1
to each of the first two crops along with 1.5 kg B ha
−1
to the first crop was sufficient to achieve satisfactory yield of the crops. Considering system productivity, nutrient uptake, and protein and Zn concentrations of crops, the aforesaid doses were found promising.
Soil micronutrients have different degrees of residual effect to crops; again crops differ in their sensitivity to micronutrient requirement. Evaluation of residual effects of micronutrient ...application to cauliflower, okra, and transplant aman rice in a pattern was studied in piedmont soil of Bangladesh. In this study, seven treatment combinations including a control treatment were tested, and the treatments were designed taking the micronutrients following the additive element trial technique. The rates of micronutrients were 3 kg zinc (Zn), 2 kg boron (B), 2 kg Cu, 3 kg manganese (Mn), 5 kg iron (Fe), and 1 kg molybdenum (Mo) per hectare. Both Zn and B were found responsive for the first crop. As second crop, okra responded to both residual Zn and B, whereas in the third crop, residual effects of only Zn were reported. Zn fertilizer need not to apply in each crop of a cropping pattern.
A study was aimed to delineate the micronutrient status, their change directive with time and relationship with other soil variables in piedmont soils of Bangladesh. Northern and Eastern Piedmont ...Plains (AEZ 22) is one of the 30 agro-ecological zones (AEZs) of the country whose bench mark status of soil micronutrient has been used for comparing with the present status. There is an indication of zinc (Zn) and boron (B) depletion to some extent after a decade of time whereas the very high fertility status of copper (Cu), manganese (Mn) and iron (Fe) prevails as it was in the previous status. In general view, the micronutrient content of surface soil (0-15 cm) was higher than those of sub-surface soils (15-30 cm). In surface soil clay content showed significant correlation with soil Zn (r=0.403··), Cu (r=0.752··), Fe (r=0.501··) and Mn (r=0.340··). Cu content of soil exhibited positive relationship with all the soil parameters except soil pH and P content; there existed highly significant negative correlation of Cu with soil pH (r=-0.578··) and P (r=-0.420··). The availability of Fe in soil was strongly related with soil clay content (r=0.501··), soil pH (r=-0.686··) and organic matter content (r=0.527··). In surface soil, Fe content influenced significantly with the content of Zn, Cu and Mn. Accordingly in sub-surface soil, positive significant interaction of Zn-Fe, Cu-Fe, Cu-Mn and Fe-Mn was observed. The message revealed from this study concerning nutrient depletion, and interactions among different soil parameters and nutrient elements will pave the way for efficient use of soil resources in a sustainable way.