A.K. Biswas

Effect of distillery effluent on seed germination in some vegetable crops.

A laboratory experiment was conducted to study the effect of different concentrations (0%, 5%, 10%, 15%, 20%, 25%, 50%, 75% and 100%) of distillery effluent (raw spent wash) on seed germination (%), speed of germination, peak value and germination value in some vegetable crops: tomato, chilli, bottle gourd, cucumber and onion. The distillery effluent did not show any inhibitory effect on seed germination at low concentration except in tomato, but in onion the germination was significantly higher (84%) at 10% concentration as against 63% in the control. Irrespective of the crop species, at highest concentrations (75% and 100%), complete failure of germination was observed. The speed of germination, peak value and germination value also followed a similar trend. We found that a concentration of 5% was critical for seed germination in tomato and bottle gourd, and 25% in the rest of the crops. Based on the tolerance to distillery effluent, the crops studied have been arranged in the following order: cucumber > chilli > onion > bottle gourd > tomato. We conclude that the effect of the distillery effluent is crop-specific and due care should be taken before using the distillery effluent for pre-sowing irrigation purposes.

Relative efficacy of different distillery effluents on growth, nitrogen fixation and yield of groundnut

A field experiment with groundnut as test crop was conducted to evaluate the manurial potential of three distillery effluents: raw spent wash (RSW), biomethanated spent wash (BSW) and lagoon sludge (LS) vis-à-vis recommended fertilizers (NPK + farm yard manure (FYM)) and a control (no fertilizer or distillery effluent). It was found that all the three distillery effluents increased total chlorophyll content, crop growth rate (CGR), total dry matter, nutrient uptake (N, P and K) and finally seed yield compared to the control but inhibited nodulation and decreased nitrogen fixation. Among the three distillery effluents, BSW produced the highest seed yield (619 kg ha(-1)) twice that of control (3.10 kg ha(-1)), followed by RSW (557 kg ha(-1)) and LS (472 kg ha(-1)). However, the distillery effluents did not influence protein and oil contents. It was concluded that these distillery effluents because of their high manurial potential could supply nutrients, particularly potassium, nitrogen and sulphur, to the crops and thus reduce the fertilizer requirement of crops. Nevertheless, the crop performance and yield with three distillery effluents were overall less than that produced by recommended NPK + FYM probably on account of failure of the effluents to supply balanced nutrition to the plants for achieving their potential growth capacity.

Effect of distillery effluents on some physiological aspects in maize

A field experiment was conducted for two years to study the effect of application of different distillery effluents: raw spent wash (RSW), biomethanated spent wash (BSW), lagoon sludge (LS), recommended NPK + FYM (farm yard manure) and control (no fertilizer and effluent) on some physiological aspects in maize. The study revealed that the application of distillery effluents resulted in increased leaf area, chlorophyll content, nitrate reductase activity total dry weight and grain yield. Among the effluents, the highest grain yield (36.9 qha(-1)) was obtained in BSW followed by RSW (32.2 qha(-1)) and LS (28.3 qha(-1)). Overall, NPK + FYM treatment recorded the highest grain yield (51.8 qha(-1)). However, to achieve the full manurial potential of the effluents, some amount of fertilizer should be supplemented.

Relationship between C addition and storage in a Vertisol under soybean-wheat cropping system in sub-tropical central India

Kinetic relationship between addition of organic carbon (through unharvested crop biomass and externally applied farmyard manure) and storage in a Vertisol (Typic Haplustert) was studied in a seven-year soybean-wheat rotation experiment. We investigated 16 treatments comprised of combinations of four annual rates of farmyard manure (0, 4, 8 and 16 t ha—1 on dry weight basis) and four annual rates of fertilizer N (0, 72.5, 145, and 230 kg N ha—1). Average annual contribution of C input from soybean was 21.65% and from wheat was 32.32% of the harvestable above ground biomass. Net increases in the contents of soil organic C (Corg) at 0—15 and 15—30 cm depth were observed in all treatments. The annual rate of Corg enrichments ranged from 85 to 739 kg C ha—1 at 0—15 cm and 54 to 149 kg C ha—1 at 15—30 cm soil depth. The observed annual rate of change in Corg (δCs/δt, kg C ha—1 yr—1) at 0-30 cm was positively correlated with the gross annual C input (A, kg C ha—1 yr—1) to the 0—30 cm soil horizon, as described by a linear equation (δCs/δt = 0.1806 × A — 160.34; r = 0.978, P < 0.01). This indicates that 18.06% of the annual gross C input was incorporated in soil organic matter.

Cadmium Phytotoxicity in Spinach with or without Spent Wash in a Vertisol

Abstract The phytotoxicity due to cadmium (Cd) and its likely contamination of the food chain—resulting from its addition from low to very high levels to a swell‐shrink clayey soil (Haplustert) in spinach (Spinacia oleracea L.)—was studied in a pot culture experiment. Twelve levels of Cd (0, 2, 4, 8, 10, 20, 40, 60, 80, 120, 160, 200 mg kg−1 soil) were applied singly and in combination with two doses (0 and 2.5 cm) of spent wash. Above 80 mg Cd kg−1 soil, there was very slow growth of spinach after germination. Spinach crop suffering from severe Cd toxicity had small roots and narrow yellowish leaves, covered in small necrotic spots. Higher levels of Cd inhibited the growth and biomass of the crop. However, application of spent wash alleviated the toxic effect of Cd to some extent. The concentration of Cd in plant parts increased when Cd was applied singly but decreased considerably when used in combination with spent wash. Cd concentration in spinach root ranged from traces (control) to 120 mg kg−1 dry matter and was directly related to soil Cd concentration. At 40 mg kg−1 soil, yield of spinach was reduced to 38% of control plants. A laboratory study was also conducted in the soils collected from treated pots after harvest in order to know the different operationally defined fractions of Cd that control the availability of Cd to spinach and that were correlated with dry‐matter yield of spinach crop.

Characterization of Zinc Oxide Nano Particles and Their Effect on Growth of Maize (Zea mays L.) Plant

In the current literature, the impact of nano-particles (NPs) on growth of higher plants has scantly been reported. An investigation was carried out to study the effect of zinc oxide nano-particles (<100 nm) on growth of maize (Zea mays L.) plant, as one of the major agricultural crops, in a solution culture system. Various concentrations of zinc (Zn) were applied through nano-zinc oxide (ZnO) particles (<100 nm) in suspension form and in ionic form through zinc sulfate (ZnSO4) salt in Hoagland solution culture. Experimental results showed that nano zinc oxide particles could enhance and maintain the growth of maize plant as well as conventional Zn fertilizer (as ZnSO4). The plant parameters like plant height, root length, root volume, and dry matter weight were all improved due to application of zinc oxide nano-particle. These findings indicate that plant roots might have the unique mechanism of assimilating nano-Zn and using for its growth and development. Different enzymatic activities were also studied and experimental results revealed that nano-ZnO particles (<100 nm) also governed the enzymatic activity of maize plant. A separate laboratory experiment was also carried out to characterize the zinc oxide nano particle for its size, zeta potential, etc.

Predicting Total Organic Carbon Content of Soils from Walkley and Black Analysis

Globally, there is problem of computing soil carbon stock because the Walkley–Black method gives only an approximation of soil organic carbon content. Until now, no universal relationship between Walkley–Black carbon (WBC) and total soil organic carbon (TOC) has been developed that could be applicable in all kinds of soil. In the present study, relationships between WBC and TOC were established from samples collected from central and northern India. TOC was measured by dry combustion technique and WBC was determined by wet digestion methods. A relationship between WBC and TOC was developed by taking into account silt + clay content (SICL) of soil and mean annual rainfall (MAR) of the region (adj. R2 = 0.99, n = 100). The present study gives an easy approach to measure TOC by easily available data sets (WBC, SICL, and MAR). Using this relationship, computation of soil carbon stock that was done earlier with WBC values could be revisited and improved.

Porosity Distribution, Surface Area, and Morphology of Synthetic Potassium Zeolites: A SEM and N2 Adsorption Study

The morphology of a synthetic zeolite (1717-nm particle-size grains; pore width 10–15 nm) as well as its surface area and mesoporosity is described. Morphology investigated by field emission scanning electron microscopy has shown cuboid crystals. The full adsorption–desorption isotherms for N2 gas measured volumetrically at 77 °K have shown type IV isotherm with type H3 hysteresis loops. To study the reliable pore-size distribution, both adsorption and desorption, curves were used by fitting the data to several well-known adsorption models: Brunauer–Emmett–Teller (BET), Barret, Joyner, and Halenda (BJH), Dollimore and Heal (D-H), Horvath–Kawazoe, and the density functional theory (DFT).

Nanostructured Natural Zeolite: Surface Area, Meso-pore and Volume Distribution, and Morphology

Analysis of meso-porosity, morphology, and textural characteristics of a commercial Indian zeolite was done experimentally using a nitrogen (N2) adsorption isotherm. Scanning electron microscope (SEM) morphology has been described for the nanostructured Indian zeolite (550-nm particle-size grains; pore width 19–22 nm) as well as its surface area and meso-porosity. The detailed surface area, pore volume, and pore size were determined from the adsorption–desorption isotherms of nitrogen measured volumetrically at 77K. To study the reliable pore-size distribution (PSD) both adsorption and desorption curves were used by fitting the data to several well-known adsorption models: Bruaner–Emmett–Teller (BET) model, Barret, Joyner and Halenda (BJH) model, Dollimore and Heal (D-H) model, Horvath–Kawazoe model, and the density functional theory (DFT) model. The sample did not contain any micropores as evident from BJH cumulative pore volume. Further morphology investigated by field emission scanning electron microscopy has shown the tubular crystals.

Sulfur accumulation in Vertisols due to continuous gypsum application for six years and its effect on yield and biochemical constituents of soybean (Glycine Max L. Merrill)

Application of S through inorganic sources is recommended to the crops in the cropping system in S deficient soils of India. However, transformations of S in the soil profile following continuous gypsum application are not known. The accumulation of S into different fractions due to application of a total of 180—540 kg S ha—1 over a six-year-period in soybean — wheat cropping system and its effect on the yield and quality of soybean produce were investigated in a vertisol area. About 25—38% of the S added was retained in the 90 cm depth of profile. Significant changes in the total S content in soil layers were recorded wherein a total of 360 kg S ha—1 or more S was applied. Maximum increase in total S content was recorded in upper layers. Soluble S accumulated more in the 30—75 cm depth; whereas, proportion of sorbed fraction of S increased with depth. Build up of S in the surface layer of the profile was mostly related to the increase in organic fraction. The S accumulation in lower layers of the profile was mostly due to increase in soluble and sorbed fractions of S. Such an increase of the S content in the soil caused an increase in seed yield, uptake of S as well as content of oil and S containing amino acids, cystine, and methionine in seed of soybean crop. Schwefelakkumulation in Vertisolen infolge sechsjahriger Gipsapplikation und Einflusse auf Ertrag und biochemische Bestandteile von Soja (Glycine Max L. Merrill) In Boden mit Schwefel (S)-Mangel in Indien wird eine mineralische S-Dungung der Pflanzen empfohlen. Die Umsetzungen des S in Bodenprofilen nach Gipsapplikation sind nicht bekannt. Die Tiefenverteilung von S-Fraktionen nach einer Dungung von insgesamt 180—540 kg S ha—1 zu einer Soja-Weizen-Fruchtfolge wurde in Vertisol-Profilen untersucht. Etwa 25—38% des zugefuhrten S verblieben in den Bodenprofilen bis 90 cm Tiefe. Signifikante Anderungen der Gesamt-S-Gehalte wurden erst ab Zufuhren von 360 kg S ha—1 nachgewiesen. In den obersten Bodenschichten stiegen die Gesamt-S-Gehalte am starksten an. Diese Anreicherungen waren insbesondere durch Erhohungen der Gehalte an organisch gebundenem S verursacht. Loslicher S wurde besonders in 30—75 cm Profiltiefe angereichert. Die Anteile an sorbiertem S stiegen mit zunehmender Profiltiefe. Erhohte S-Gehalte in den unteren Profilteilen waren vor allem auf die losliche und sorbierte Fraktion des S zuruckzufuhren. Die erhohten S-Gehalte der Boden bedingten hohere Ertrage, S-Aufnahme, Olgehalte und Gehalte der S-haltigen Aminosauren Cystin und Methionin in den Sojabohnen.