Sushanta Kumar Naik

Effect of split application of zinc on yield of rice (Oryza sativa L.) in an inceptisol

Abstract Rice is mostly transplanted under puddled low land soil conditions in India, where Zinc (Zn) deficiency is a common problem. The objective of this study was to find out the efficacy of split application of Zn on growth and yield of rice in an inceptisol. The split application of Zn as ZnSO4 · 7H2O performed better than its single basal application, while the split application of Zn-EDTA did not show any significant difference on yield and yield components of rice over its single basal application. Zn-EDTA was found to be better for growth and yield of rice among the two sources of Zn. The soil application of Zn at 1.0 kg ha−1 as Zn-EDTA (T7) recorded highest grain yield of 5.42 t ha−1, filled grain percentage of 90.2%, 1000-grain weight of 25.41 g and number of panicles m−2 of 452. The Zn content of grain and straw were found to be maximum in the treatment T7 i.e. 38.19 and 18.27 mg kg−1, respectively. Linear regression studies indicated that grain yield of rice is significantly influenced by Zn content of grain, Zn content of straw and DTPA extractable Zn content of soil at the level of 95.96, 96.74 and 95.57%, respectively.

Influence of Lime and Organic Matter on the Mobility of Cadmium in Cadmium-Contaminated Soil in Relation to Nutrition of Spinach

Cadmium and cadmium compounds are water soluble, mobile in most soils, bio-available, and tend to bio-accumulate. A pot culture experiment was conducted on contaminated soil to study the influence of lime and organic matter on the mobility of cadmium in spinach and its rhizosphere soil. Application of lime (50% and 100% lime requirement) and organic matter (0.5 and 1% by weight of soil) to soil decreased the availability of Cd to the soil and plant throughout the crop growth. The highest diethylene triamine penta-acetic acid (DTPA) extractable Cd was 10.84 mg kg−1 in the treatment OM0 L0 (No application of organic matter and lime) at 20 days after sowing of spinach. Likewise, the highest Cd concentration in spinach roots and shoots were 19.80 and 17.0 mg kg−1 in the treatment OM0 L0 at 20 days after sowing. The Cd concentration in spinach roots and shoots were decreased by 63.23 and 71.88%, respectively, in the treatment OM1 L100 (application of FYM at 1.0% by weight of soil and lime at 100% lime requirement) after 60 days of growth. The lowest concentrations of Cd in the soil and plant after the harvest of the crop were 2.88 and 4.27 mg kg−1, respectively, in the treatment OM1 L100 and resulted in 65.75 and 71.55% decrease over control (OM0 L0). The highest total chlorophyll content of leaves was 2.19 mg kg−1 of fresh weight in the treatment OM1 L100 at 40 days of crop growth.

Effect of lime, humic acid and moisture regime on the availability of zinc in Alfisol.

Lime and humic acid application can play an important role in the availability of zinc in paddy soils. We conducted laboratory incubation experiments on a rice growing soil (Alfisol) to determine the effect of lime, humic acid and different moisture regimes on the availability of Zn. Addition of half doses of liming material (powdered lime stone) recorded highest values of DTPA-Zn followed by no lime and 100% of lime requirement throughout the incubation period. With the progress of incubation, DTPA-Zn increased slightly during the first week and then decreased thereafter. The highest DTPA-extractable Zn content of 2.85 mg/kg was found in the treatment Zn10 L1/2 at 7 days of incubation, showing 17.3 % increase in DTPA-Zn content over its corresponding treatment of Zn alone (Zn10L0). The DTPA-Zn concentration increased with the application of humic acid compared with no humic acid throughout 35 days of the incubation period and the peak value obtained was 3.12 mg/kg in the treatment Zn10 HA2 at 14 days after incubation, showing 50 % increase in Zn content over its corresponding treatment of Zn alone (Zn10HA0). The application of 0.2% humic acid compared with 0.1% resulted in greater increase in DTPA-Zn concentration in soil application. During the 35 days of incubation, highest values of DTPA-Zn were recorded in soil maintained at saturated compared to water logged conditions. However, under alternate wetting and drying condition the DTPA-Zn content gradually decreased up to 21 days and thereafter increased slowly.

Mobility of lead and nickel in soil in relation to nutrition of sesame

The availability of lead and nickel in soil is greatly influenced by farmyard manure. We conducted two pot culture experiments in an Aeric Haplaquept to study the mobility of lead and nickel in soil and their uptake by sesame (Sesamum indicum L.) plant as influenced by the application of farmyard manure. Application of lead (0–500 mg kg−1) and nickel (0–500 mg kg−1) at different doses to soil and plant increased their availability and such increase was counteracted by the application of farmyard manure (0–3% by weight of soil). The lead and nickel concentrations in soil and shoot dry matter of sesame gradually decreased with the progress of crop growth. The highest DTPA-extractable Pb and Ni was 119.3 and 215.5 mg kg−1 in the treatment Pb500 and Ni500, respectively, at 15 days of incubation. The highest Pb and Ni concentrations in the shoot of sesame plant were 23.8 and 24 mg kg−1observed in the treatment Pb500 and Ni500, respectively, at 15 days of crop growth. The toxic limit of applied Pb and Ni concentration to soil for shoot growth of sesame plant was 50 and 100 mg kg−1, respectively.

Evaluation of nitrosulf and elemental sulphur on growth and yield of rapeseed (Brassica campestris L.) in India

Field experiments were conducted at the farmers field in Adhata village, Amdanga block, North 24 Parganas, West Bengal, India, during the dry season of 2005–2006 and 2006–2007 in an inceptisol (pH 6.8) to evaluate the nitrosulf and elemental sulphur on the growth and yield of rapeseed (cv. B 9). Indeed, there are only four rates of nitrosulf and two rates of elemental S which were applied to the soil. The total S content in dry matter of rapeseed gradually increased up to 80 days of crop growth when S was applied either as nitrosulf or elemental S, being greater with nitrosulf compared to elemental S application. The highest mean S uptake by rapeseed and straw was 286 and 190% increase over that of the control, respectively, in the treatment T5 (0.2% S as nitrosulf). The mean plant height, number of siliqua plant−1, number of seeds siliqua−1 and thousand seed weight were highest in treatment T5 with 20, 34.8, 42.9 and 18.9% increase over that of the control, respectively. The yield of seed and stover recorded highest percentage increase of 66 and 71.6%, respectively, in the treatment T5 over that of the control during both the years.

Evaluation of Major and Micronutrient Status of Acid Soils of Different Mango Orchards

The study involved distribution of nutrient elements in the acid soils of mango orchards. The objectives were to evaluate pH, organic carbon, and available macronutrient and diethylene triamine pentaacetic acid (DTPA)-micronutrient content in the soil profile. Depth wise (0–30, 30–60, 60–90, and 90–120 cm) soil samples were collected from 27 different mango orchards comprising of three health levels (unhealthy, medium, and healthy) and three age groups (1–3 years, 4–5 years, and 6–7 years). The pH of the surface soil was low and gradually increased with an increase in depth irrespective of health and age levels of the orchard. The pH was higher under the healthy orchard of 4–5 years old (6.00 at surface layer) and recorded 30% more compared to control (unhealthy orchard of 1–3 years old). The organic carbon was highest of 6.3 and 6.2 g kg−1 in A3H3 (healthy orchard of 6–7 years old) and A2H3 (healthy orchard of 4–5 years old), respectively, in the surface soil layer. The N content was higher under A1H3 (healthy orchard of 1–3 years old), A2H3, and A3H3 (142.2, 138, and 138 kg ha−1, respectively, in surface layer); whereas P and K were higher under A2H3 and A3H3 orchard (12 and 380.5 kg ha−1, respectively, in surface layer) than other orchards. The DTPA-extractable Fe and Mn contents were high status throughout the soil profile; whereas DTPA-extractable Zn and Cu were higher under A2H3 orchard (0.48 and 1.39 mg kg−1, respectively, in surface layer).

Diagnostic Leaf Nutrient Norms and Identification of Yield-Limiting Nutrients of Mango in Eastern Plateau and Hill Region of India

ABSTRACT The leaf nutritional status of mango orchards was assessed using diagnosis and recommendation integrated system (DRIS). The DRIS norms, which showed higher variance and lower coefficients of variation, are found to have greater diagnostic precision. As per DRIS indices, a relative deficiency for magnesium, zinc, and boron corresponding to relative sufficiency for calcium, nitrogen, phosphorus, sulfur, and potassium was detected in 9-year-old mango orchards. For the younger orchards (6–7 year old), the order of requirement of nutrients was found to be calcium > sulfur > potassium > boron > nitrogen > phosphorus > magnesium > zinc. Boron was found as the most yield-limiting elements in all age group of plants. When the DRIS indices were compared on the basis of soil pH, calcium and magnesium were most yield-limiting nutrients below pH 5.5, while nitrogen, zinc, and boron were found to be most limiting above pH 5.5.

Rates of decomposition and nutrient mineralization of leaf litter from different orchards under hot and dry sub-humid climate

ABSTRACT Leaf litter decomposition is a critical step in nutrient cycling and providing nutrients to plants. Decomposition of dry matter, lignin, ligno-cellulose, cellulose and polyphenols was investigated in relation to nitrogen (N), phosphorus (P) and potassium (K) dynamics in leaf litter of mango, guava and litchi orchards under hot and dry sub-humid climate. Leaf litter of mango and guava decomposed more rapidly than that of litchi with decay constants of 3.22, 1.33 and 0.62 yr-1, respectively. The leaf litter organic substances like polyphenol lost more rapidly followed by cellulose, lignin and ligno-cellulose throughout the period of decomposition. The N was released faster both in mango and guava with decay constant of 4.06 and 2.11 yr-1, respectively. The release of K was faster in mango followed by guava and litchi with decay constant of 4.66, 3.18 and 1.63 yr-1, respectively. The leaf litter decomposition was significantly positively correlated with soil fungal and bacterial biomass, rainfall and air temperature, while the leaf chemistry showed significant negative correlations in all the orchards. The results demonstrated that mango leaf litter was found to be the best followed by guava, and litchi in terms of N, P, and K return in less period of time.

Predictive models for dry biomass and carbon stock estimation in Litchi chinensis under hot and dry sub-humid climate

ABSTRACT Accurate and reliable predictive models are necessary to estimate above and below ground biomass of plant and biomass carbon stock non-destructively. Different growth models namely viz, Linear, Allometric, Logistic, Gompertz, Richard’s, Negative exponential, Monomolecular, Mitcherlich and Weibull were fitted to the relationship between dry biomass of litchi tree components with collar diameter. Richard’s model outperformed the others and fulfilled the validation criterions to the best possible extent with lowest Akaike information criteria (AICc) of 90.47 and root mean square error (RMSE) of 1.79. The value of adjusted R2 ranged from 0.947 to 0.971 for the Richard’s models fitted on various biomass components and the ‘t’ values for all the components was found non-significant (p > 0.05) indicating the validation of the model. The estimated total dry biomass varied from 0.50 Mg ha−1 in two year to 5.71 Mg ha−1 in 10 year old litchi orchards. The estimated stored biomass carbon stock in litchi orchards (branches, bole and roots) varied from 0.10 Mg ha−1 in two year to 1.85 Mg ha−1 in 10 year orchards with CO2 sequestration potential from 0.19–4.63 Mg ha−1.

Effect of Substrate, Nutrition and Growth Regulator on Productivity and Mineral Composition of Leaf and Pseudobulb of Cymbidium Hybrid “Baltic Glacier Mint Ice”

ABSTRACT The study evaluates the effect of various potting media, nutrition, and growth regulators on production and nutrient composition of leaf and pseudobulb of Cymbidium hybrid “Baltic Glacier Mint Ice” grown in greenhouses. The results confirmed a positive influence of growth and nutrition on flower yield of Cymbidium, with shredded tree bark+ coconut husk + brick bits giving the best flowering. A nitrogen, phosphorus and potassium (NPK) dose of 200:200:200 mg l−1 with benzyl adenine (BA) and gibberellic acid (GA3) at 50 mg l−1 was found best for growth while an NPK dose of 200:100:100 mg l−1 with BA and GA3 at 50 mg l−1 was suitable flower production of Cymbidium hybrid. Application of an NPK dose of 300:200:300 mg l−1 with BA and GA3 at 500 mg l−1 was found to be best for enhancing flowering frequency. Plants of the Cymbidium hybrid with the best flowering characteristics mostly contained significantly higher concentrations of nitrogen (N), phosphorus (P) and potassium (K) in leaves and pseudobulbs (which acts as reservoir of nutrients).