Dr Sudhir Verma
@yspuniversity.ac.in
Principal Scientist, RHRSS & KVK, Lahaul & Spiti II at Tabo
Dr. Yashwant Singh Parmar University of Horticulture and Forestry, Solan
Scopus Publications
Scopus Publications
Pankaj Panwar, Sharmistha Pal, Sudhir Verma, Nancy Loria, Med Ram Verma, V. K. Bhatt, and N. K. Sharma
Springer Science and Business Media LLC
Santosh Watpade, Rakesh Kumar, Pooja Bhardwaj, Kallol Kumar Pramanick, Arun Kumar Shukla, Baswaraj Raigond, Jitender Kumar, Usha Sharma, Sumit Vashisth, and Sudhir Verma
Springer Science and Business Media LLC
Divya Mittal, Rakesh Shukla, Sudhir Verma, Anand Sagar, Kartar S. Verma, Anita Pandey, Yashwant Singh Negi, Reena V. Saini, and Adesh K. Saini
Elsevier BV
Abstract Plant growth promoting microbes impact the life of trees, shrubs and other plant species in the forest. Fire in forest adversely affects the growth of plants directly by burning and heat stress and indirectly by affecting the survival of plant growth promoting microbes. Herein, we analyzed changes in the population of cultivable microbes owing to fire in the pine grown forest in the Indian Himalayan region. We found that soil in the burnt region predominantly harbored Gram-positive bacteria which lacked biofertilizer and biocontrol traits. Forest fire resulted in the loss of Gram-negative strains of genera Pseudomonas, Serratia, Enterobacter, Burkholderia, Klebsiella, and Pantoea. Similarly, we found that the rhizospheric region of grasses which came after the event of the fire in the pine forest lacked the beneficial Gram-negative strains. Furthermore, in plantae experiments in which pea (Pisum sativum) and wheat (Triticum aestivum) seedlings were treated with bacteria isolated from the burnt and unburnt forest bed showed that bacteria from the burnt region did not affect the growth of seedlings as compared to the bacteria isolated from the unburnt region which improved the growth of seedlings. Comparing the soil parameters between burnt and unburnt region showed a decrease in nutrients, and, increase in both bulk density and dispersion ratio due to the forest fire. Our results strongly indicate that forest fire reduces the population of cultivable beneficial microbes and this loss could have a negative impact on the growth of forest flora.
Pramod Jha, S. Verma, R. Lal, C. Eidson, and G. S. Dheri
Wiley
Residue retention and reduced tillage are both conservation agricultural practices that may enhance soil organic carbon (SOC) stabilization in soil. We evaluated the long-term effects of no-till (NT) and stover retention from maize on SOC dynamics in a Rayne silt loam Typic Hapludults in Ohio. The six treatments consisted of retaining 0, 25, 50, 75, 100 and 200% of maize residues on each 3 × 3 m plot from the crop of previous year. Soil samples were obtained after 9 yrs of establishing the experiment. The whole soil (0–10 and 10–20 cm of soil depths) samples under different treatments were analysed for total C, total N, recalcitrant C (NaOCl treated sample) and 13C isotopic abundance (0–10 cm soil depth). Complete removal of stover for a period of 9 yrs significantly (P < 0.01) decreased soil C content (15.5 g/kg), whereas 200% of stover retention had the maximum soil C concentration (23.1 g/kg). Relative distribution of C for all the treatments in different fractions comprised of 55–58% as labile and 42–45% as recalcitrant. Retention of residue did not significantly affect total C and N concentration in 10–20 cm depth. 13C isotopic signature data indicated that C4-C (maize-derived C) was the dominant fraction of C in the top 0–10 cm of soil layer under NT with maize-derived C accounting for as high as 80% of the total SOC concentration. Contribution of C4-C or maize-derived C was 71–84% in recalcitrant fraction in different residue retained plots. Residue management is imperative to increase SOC concentrations and long-term agro-ecosystem necessitates residue retention for stabilizing C in light-textured soils.
J. K. Ladha, A. Tirol-Padre, C. K. Reddy, K. G. Cassman, Sudhir Verma, D. S. Powlson, C. van Kessel, Daniel de B. Richter, Debashis Chakraborty, and Himanshu Pathak
Springer Science and Business Media LLC
Industrially produced N-fertilizer is essential to the production of cereals that supports current and projected human populations. We constructed a top-down global N budget for maize, rice, and wheat for a 50-year period (1961 to 2010). Cereals harvested a total of 1551 Tg of N, of which 48% was supplied through fertilizer-N and 4% came from net soil depletion. An estimated 48% (737 Tg) of crop N, equal to 29, 38, and 25 kg ha−1 yr−1 for maize, rice, and wheat, respectively, is contributed by sources other than fertilizer- or soil-N. Non-symbiotic N2 fixation appears to be the major source of this N, which is 370 Tg or 24% of total N in the crop, corresponding to 13, 22, and 13 kg ha−1 yr−1 for maize, rice, and wheat, respectively. Manure (217 Tg or 14%) and atmospheric deposition (96 Tg or 6%) are the other sources of N. Crop residues and seed contribute marginally. Our scaling-down approach to estimate the contribution of non-symbiotic N2 fixation is robust because it focuses on global quantities of N in sources and sinks that are easier to estimate, in contrast to estimating N losses per se, because losses are highly soil-, climate-, and crop-specific.
Anup Das, Rattan Lal, Upender Somireddy, Catherine Bonin, Sudhir Verma, and Basant Kumar Rimal
CSIRO Publishing
The issue of carbon (C) neutrality and the environmental advantages and variations in soil organic C (SOC) stocks under biofuel crops need to be addressed thoroughly and objectively. Thus, the aim of this study was to compare the impact of annual biofuel crops (no-till maize, Zea mays L.; sorghum, Sorghum bicolor L.) and perennial lignocellulosic grasses (switch grass, Panicum virgatum L.; miscanthus, Miscanthus × giganteus; and prairie mix) on soil properties and SOC stock in central Ohio. Two years of perennial energy crops improved soil properties in terms of lower soil bulk density, higher porosity, improved water-stable aggregates (WSA), higher mean weight diameter, pH and electrical conductivity compared with those under maize and sorghum. The WSA in the 0–10 and 10–20 cm soil layers were higher under miscanthus (94.7% and 91.8%, respectively) and switch grass (92.7% and 89.4%) than under maize (89.9% and 86.1%) and sorghum (85.1% and 85.4%). Macroaggregates (>0.25 mm diameter) contained higher concentrations of C and nitrogen (N) than microaggregates. Macroaggregates in soil under sorghum and maize contained 17.3% and 14.2% less C and 22.8% and 15.2% less N in 0–10 cm layer, and 29.8% and 24.2% less C and 22% and 7.1% less N in 10–20 cm layer, than macroaggregates under switch grass (15.82 g C kg–1 in 0–10 cm and 14.06 g C kg–1 in 10–20 cm layers), respectively. The SOC stock in the 0–10 cm layer, on an equivalent soil-mass basis, was significantly higher under switch grass (28.5 Mg C ha–1) and miscanthus (28 Mg C ha–1) than that under sorghum (24.8 Mg C ha–1). Thus, only switch grass and miscanthus sequestered C, whereas other species had no or negative effect, with loss of soil C under sorghum in 2 years. There is a need for long-term studies and estimation of SOC stock in deeper layers to establish the SOC balance under biofuel crops.
G. S. Dheri, Rattan Lal, and Sudhir Verma
Informa UK Limited
Application of nitrogenous fertilizers in agriculture is a major source of anthropogenic N2O emission. Choice of nitrogenous fertilizer with a low emission potential can reduce global nitrous oxide (N2O) emissions. We studied effects of urea (U), ammonium nitrate (AN), sulfur-coated urea (SU), and compost (C) application on the concentration of N2O in soil air of mesic Typic Hapludalfs and corn (Zea mays L.) growth in a greenhouse experiment conducted at The Ohio State University. In the urea-treated soil, N2O concentration (2.35 μl l−1) increased significantly (p = 0.05) over that in the unfertilized soil (0.21 μl l−1). The increase in N2O concentration for AN, SU, and C treatments over the unfertilized soil was 748%, 681%, and 48%, respectively. Soil treated with mineral fertilizers produced significantly (p = 0.05) higher N2O concentration in comparison with that in the unfertilized and compost-treated soils. The highest shoot biomass of 52.8 g pot−1 was recorded in SU-treated soil and the lowest of 33.4 g pot−1 in unfertilized soil. Soil treated with SU produced the highest root biomass (59.0 g pot−1) followed by that for AN (54.7 g pot−1), U (53.7 g pot−1), and C (36.7 g pot−1), and the lowest root biomass was recorded in the unfertilized soil (33.2 g pot−1). The highest and the lowest root volume were recorded in soil treated with SU (357 cm3) and unfertilized soil (177 cm3), respectively. The slow-release fertilizers (i.e., sulfur-coated urea) lowered concentration of N2O in the soil air.
Kartar Singh Verma, Mahadev Singh Mankotia, Sudhir Verma, and Vikas Kumar Sharma
Springer India
The ecosystems which are most vulnerable to the specter of climate change are high mountain areas such as Himalayas. In Northwestern Himalayan region covering the states of Himachal Pradesh, Jammu, and Kashmir besides Uttrakhand, very limited studies on climate change have been done. Hence, considering the past and present climatic trends, future climatic scenario of Himachal Pradesh has been studied. Himachal Pradesh is a mountain state of north India, located between 30° 22′ 40″ to 33° 12′ 40″ N latitude and 75° 47′ 55″ to 79° 04′ 20″ E longitude. It has large dissimilarity in physiographic features and experiencing varied changes in warming and precipitation due to global warming, which will be both negative and positive, to horticulture production. Future climate will determine the suitability of fruit crops to their current locations. Climatic conditions likely to occur in Himachal Pradesh during 2021–2050 are analyzed and termed as mid-period compared to baseline period (1960–1990) using HADRM3 model under scenario A1B. The climatic parameters included are maximum temperature (Tmax), minimum temperature (Tmin), and rainfall. District-wise changes, likely to occur, in the above parameters and their implications to fruit cultivation have been discussed in this chapter.
Sandeep Sharma, Girish Chander, T. S. Verma, and Sudhir Verma
Informa UK Limited
A long-term field experiment with rice-wheat cropping was started in the wet season of 1988 with four levels of lantana (Lantana camara L.) (0, 10, 20, and 30 Mg ha−1 on fresh weight basis) and three tillage practices (No puddling, puddling, and soil compaction). From wet season of 1997, however, three tillage practices were replaced with three levels of nitrogen (N) and potassium (K) to rice (33, 66, and 100% of recommended) and 66% of recommended N, phosphorus (P), and K to wheat. Phosphorus was totally omitted for the rice crop. The recommended N and K for rice was 90 and 40 kg ha−1, whereas the recommendations for N, P, and K for wheat were 120, 90 and 30 kg ha−1. Organic amendments are known to improve soil productivity under rice-wheat cropping by improving physical conditions and nutrient status of the soil, but their availability is restricted. There is a need to identify locally available and cost-effective organic materials that have minimal alternate uses as fodder and fuel. We evaluated Lantana camara L. residues, a fast-growing weed in nearby wastelands, as a potential soil organic amendment. Among the different fractions of K, nonexchangeable K was dominant followed by exchangeable and water soluble K. The incorporation of lantana (10 to 30 Mg ha−1) over the last 12 years has resulted in a significant build-up of all the K fractions, the maximum being in water-soluble K (10 to 32%) followed by exchangeable K (18 to 27%) and least in nonexchangeable K (5 to 7%) over no lantana incorporation. The increasing levels of these two inputs significantly and consistently increased ammonium acetate (NH4OAc)- extracted K (available K) content in soil and also resulted in significantly higher accumulation of K by the crops during the years of experimentation. Among different K fractions, exchangeable K was observed to be the most important K fraction contributing towards wheat and rice yields as well as K accumulation by wheat and rice. Stepwise multiple regression equations indicated that exchangeable K was the most important variable contributing towards total variation in grain yield and K accumulation by wheat or rice.
Sudhir Verma and Pradeep K. Sharma
Elsevier BV
Abstract Effect of different cropping systems, viz. maize–wheat (M–W), rice–wheat (R–W), soybean–wheat (S–W), and perennial grasses (guinea grass and setaria grass), in vogue since 6–32 years, and long-term use of chemical fertilizers (N, NP, NPK and NPK + lime) and organic materials (FYM, wheat straw, lantana biomass) on physical productivity of medium-textured (silt loam and silty clay loams) soils was investigated using non-limiting water range (NLWR) as the soil physical index. Higher the NLWR better is the soil physical condition for crop growth. The sources of N, P and K were urea, single superphosphate and muriate of potash, respectively. The NLWR was highest in S–W (16.8%), followed by grasses (14.4–15.6%) and M–W (13.1–15.4%), and lowest in R–W (7.5–11.0%). Under M–W system (32 years), NLWR was highest in NPK (13.1%), followed by NP (12.2%), NPK + lime (9.4%) and control (9.0%), and lowest in N (7.7%). Application of organics increased the NLWR in both M–W and R–W (6–18 years) systems; the NLWR values with and without organics were 18.0 and 17.1% in M–W, and 14.1–15.9 and 15.7–17.2% in R–W system. The NLWR was linearly, significantly and positively correlated with wheat grain yield ( r = 0.646**, −0.706**). The NLWR:PAWC (plant available water capacity) ratio (higher the ratio, better is the soil physical condition), which was 0.58 in control, decreased with N (0.49) but increased with NP (0.72) and NPK application (0.77); use of organics further improved the ratio. The NLWR:PAWC ratio was highest in S–W (0.97), followed by grasses (0.88–0.91), M–W (0.77–0.86) and R–W (0.54–0.68) system. Thus, long-term use of urea alone deteriorated, while NPK at recommended rates improved soil physical productivity over the control of no fertilizer application; the effect further improved when NPK were combined with organic sources. Among different cropping systems, the soil physical productivity followed the order: S–W > grasses > M–W > R–W system.
Sudhir Verma and Pradeep Kumar Sharma
Springer Science and Business Media LLC
We investigated C management index (CMI; an indicator of sustainability of a management system and is based on total and labile C) and soil aggregation in medium-textured soils (silt loam and silty clay loam) under different cropping systems as follows: maize-wheat (M-W), rice-wheat (R-W), soybean-wheat (S-W), Guinea grass, and Setaria grass. Field experiments were 6–32 years long and were located in the wet-temperate zone of northwest Himalayas. The plant nutrients were applied through chemical fertilizers (urea, superphosphate, and muriate of potash) with or without organic materials (FYM, wheat straw, and Lantana spp.). The content of total C (CT), labile C (CL), CMI, mean weight diameter (MWD), and aggregate porosity varied significantly under different cropping systems. The range was 1.59 (R-W)–4.29% (Setaria) for CT, 1.23 (R-W)–3.89 mg/kg (Guinea grass) for CL, 52.09 (R-W)–129.77 (Guinea grass) for CMI, 0.90 (R-W)–5.09 (Guinea grass) for MWD, and 41.5 (R-W)–56.8% (S-W) for aggregate porosity. Aggregate porosity was highest (56.8%) under S-W, followed by grasses (50.1–51.2%), and M/R-W (41.5–50.0%). As per these data, (a) continuous use of N alone as urea lowered soil sustainability over control (no fertilizers); (b) use of NPK at recommended rates improved soil productivity over control; (c) the NPK + organic amendments further improved soil sustainability; and (d) the sustainability under different cropping systems followed the order: perennial grasses > soybean-wheat > maize-wheat > rice-wheat.
S. Verma, S.K. Subehia, and S.P. Sharma
Springer Science and Business Media LLC
The effect of different treatments on the fate of applied P was investigated in a long-term field experiment started in 1972–1973 following a maize–wheat sequence. The soil samples were collected after 29 years of continuous addition of mineral fertilizers and amendments such as farmyard manure (FYM) and lime. The total P content of all the treatments increased compared to the original soil; NaOH-inorganic P (Pi) (NaOH-Pi) representing Fe and Al-bound P was the dominant Pi fraction. At the beginning of the experiment (1972–1973), the various P pools could be quantitatively ranked in the following order: residual P>NaOH-organic P (Po)>NaOH-Pi>NaHCO3-Po>NaHCO3-Pi>HCl-P>H2O-P. As a result of continued P fertilization and cropping, the order changed as follows: residual P>NaOH-Pi>NaOH-Po>NaHCO3-Pi>NaHCO3-Po>HCl-P>H2O-P. Compared to the imbalanced mineral fertilizer application, the balanced as well as integrated application of nutrients resulted in significantly lower P adsorption capacity of soils. The Olsen extractable-P fraction (plant-available P) increased from about 12 mg kg−1 soil in 1972 to about 81 mg kg−1 soil in the treatments receiving P for the last 29 years.