4. CROP AND NATURAL RESOURCE MANAGEMENT FOR SUSTAINABLE ENVIRONMENT
4.8 CESCRA
Nangalbhoor (Pathankot), Bhangwa (Gurdaspur), Bal
& Kohali (Amritsar), and Pheowa (Kurushetra). The liquid culture was inoculated @ 10 litres per acre and field was ploughed with rotavator and wheat was sown after 15 days. Demonstrations were also carried out at KVK Panipat, Mohali, Ujwa and Saharanpur for farmers. In collaboration with MNREGA a large scale demonstration was held at village Puranpur, Pilibhit for pit composting of various residues.
Farmers’ participatory on-farm trials (OFT) on carrier based as well as liquid formulation bio- fertilizers, namely, blue green algae (BGA), Rhizobium, Azotobacter, Azospirillum, phosphate solubilizing bacteria (PSB), AM fungi and Azolla were conducted in farmers’ fields in collaboration with 21 KVKs located in 12 states (J&K, Punjab, Bihar, Jharkhand, Gujarat, Rajasthan, Chhatishgarh, Odisha, Madhya Pradesh, Uttar Pradesh, Uttarakhand and West Bengal). Crops included food, pulse, oilseed, vegetable, plantation crops. The feedback received from the farmers depicts that integrated application of BGA and other biofertilizers are cost-effective, eco-friendly and easy to use. Average increase in rice grain yield across the locations due to application of BGA and PSB varied between 3.4-8.5% over the farmers’ practices.
Biofertilizer applied plots had bolder and shiny rice grains, and less lodging. BGA application led to marked improvement in soil physical condition and saved 10-25 kg N/ ha. In pulses, increase in yield due to Rhizobium inoculation was 11.4-16.8% in green gram, 10.6-15.4% in chickpea and 10.8-16.7% in field pea.
Also considerable increment in yield (3.2-7.6%) was found in brinjal due to biofertilizer inoculation. Liquid formulations of Azotobacter, Azospirillum, ZnSB and KSB were found user-friendly, effective and potential sources of crop nutrition in rice, brinjal and other crops at different locations in India. Inoculation of these liquid formulations increased wheat grain yield by 4.8- 12.5%, 3.4-10.2%, 3.5-7.2% and 2.4-5.6%, respectively over the farmers’ practices across the locations.
4.7.15 Bioresources
Whole genome sequence of Azotobacter chroococcum W5 (MTCC 25045) an indigenous free living diazotroph
has been deposited at DDBJ/EMBL/GenBank under Bioproject ID: PRJNA610299. This bacterium has been isolated from wheat rhizosphere long back and has been recommended as a Biofertilizer for many crops, including vegetables, agronomically tested and evaluated. The strain has been formulated as liquid formulation with a shelf life of more than 2 years, and the technology has been commercialized and applied for patent. Seven oleaginous yeasts have been submitted to NBAIM, Mau, viz:
Trichosporon mycotoxinivorans S2 (NAIMCC-F-03902);
Candida tropicalis Pe1 (NAIMCC-F-03903); Candida dubliniensis Pe2(NAIMCC-F-03904); Meyerozyma caribbica Pe3 (NAIMCC-F-03905); Candida tropicalis Po2 (NAIMCC-F-03906); Candida tropicalis L2 (NAIMCC-F-03907); Candida quercitrusa L3 (NAIMCC-F-03908). 16S rRNA sequences of fifteen siderophore chemotyped bacterial isolates (Accession No. MK253238- MK253251) and 10 heavy metal remediating bacterial isolates (Accession No.
MN524169-MN524178) have been deposited in NCBI.
Besides, partially characterized and identified 30 unialgal freshwater cyanobacteria cultures belonging to 12 genera have been deposited at BGA Germplasm, CCUBGA, IARI, New Delhi, which is repository and service centre for fresh water blue green algae maintained in unialgal condition.
progressive climate change and variability in kharif and rabi seasons in India towards the end of the century.
4.8.2 Climate change impacts and adaptations in rice and wheat
Climate change is projected to affect the wheat productivity by -3.2 to 5.3% in 2020 (2010-2039); -8.4 to -19.3% in 2050 (2040-2069); and -18.9 to -41% in 2080 (2070-2099) under different representative concentration pathways (RCPs). States like Bihar, Jharkhand, West Bengal are particularly vulnerable.
More inter-annual variability in wheat yield is projected. Adaptation will improve the yield at state level in the range of 10 to 40% in major wheat growing states. However, many current management options may become unsuitable in future climates to sustain wheat yield. Developing short-duration heat tolerant varieties is important for sustaining wheat yield in central India. The irrigated rice yield during kharif season is projected to be affected by approximately -3%, -2 to 3.5% and 2 to 5% in 2020, 2050 and 2080 climate scenarios, respectively in all RCPs. The spatial variation indicated that in the states of Haryana, Karnataka, Kerala, Maharashtra, Tamil Nadu and West Bengal significant negative impacts are projected without adaptation. Growing short duration varieties with improved nutrient and water management can enhance the productivity up to 28% till 2050 climate scenarios but with significant inter-annual and spatial variations.
Rainfed rice productivity is projected to change in the range of 7 to -28% in 2020; 2 to -20% in 2050 and -10 to -47% in 2080 climate scenarios in different RCPs with significant spatial variation. It is projected that growing short duration stress tolerant high yielding
varieties can improve the yield up to 28% in rainfed rice regions in India till 2050 scenario. But to sustain rainfed rice yieldsbeyond 2050, high yielding heat and water stress tolerant varieties need to be developed. In addition, field level water managementwill be crucial.
4.8.3 Greenhouse gas emission in organic and inorganic grown rice-wheat-mung bean system
Experimental results showed highercumulative methane(CH4) and carbon dioxide(CO2) emission from rice-wheat-mungbean systems under organic plots where FYM + crop residue (CR) + biofertiliser (B) and vermicompost (VC) +CR+B were applied compared to conventional inorganicfertilized plots. Global warming potential (GWP) of various treatments varied from 602.3 to 1869.9, 569.7 to 1703.6, and 568.8 to 1665.0 kg CO2 eq. ha-1 during rice, wheat and mungbean,respectively.
Among soil properties, SOC exhibited positive and significant relationships with CH4 and CO2 flux from rice, wheat and mungbean crops. Similarly, N2O flux was also had positive correlation with total N, NO3- -N, and NH4+-N. Soil microbial biomass carbon (MBC) had positive association with CH4 and CO2 flux from rice, wheat and mungbean crops. Soil enzymes like dehydrogenase, α-and β-glucosidase were positively correlated with CO2 and CH4 emission.
4.8.4 Greenhouse gas mitigation through different fertilizer management options
Recommended dose of fertilizer (RDF) reduced 24-29% methane emission in rice at Varanasi. Methane Global warming potential and yield of rice-wheat system in Varanasi under different fertilizer treatments
Treatments Rice (Var. Swarna Sub-1) Wheat (HUW 234) Rice- wheat
system CH4 (kg ha-1) N2O (kg ha-1) Yield (t ha-1) N2O (kg ha-1) Yield (t ha-1) GWP
(kg CO2 eq ha-1)
Control (no fertilizer ) 12.81 0.52 2.80 0.533 1.8 634.0
Farmer practice
(NCU, 121:74:00 ) 20.85 1.23 5.80 1.353 5.5 1290.9
RDF (+Microbial culture) 14.78 1.19 7.10 1.159 6.11 1069.5
RDF (NCU) 15.78 1.15 7.00 1.153 6.17 1080.7
Polymer coated urea 14.27 1.02 7.15 0.976 6.05 951.5
emission was reduced by 6.3 and 9.5 % with microbial intervention and polymer coated urea, respectively in rice compared to RDF. A reduction of 17.16%, 15.6% and 26.3% in global warming potential (GWP) was observed with microbial intervention, RDF and application of polymer coated urea, respectively compared to farmers practice in rice-wheat system The grain yield was increased by 17.1-22.4% in rice and by 9-11% in wheat with microbial intervention, RDF and application of polymer coated urea treatments compared to farmers practice.
4.8.5 Mitigating methane using microbial interventions
A field experiment was conducted in rice using liquid formulation of MNL7 and MaAL 69 consortium of methane oxidizing bacteria (MOB) through seedling root dip technology and as spray formulation at tillering and panicle initiation stage in four rice varieties of Pusa -44, IR-64, CR Dhan 310 and MTU 1010 and their effect on methane emission from rice soil was quantified (Table).The presence of methane oxidizing bacteria (methanotrophs) reduced methane by 7 to 11% under the different rice varieties.
4.8.6 Reducing nitrous oxide emissions in wheat
The effect of urease inhibitor on neem coated urea was evaluated for reducing nitrous oxide emissions inwheat. Limuswas used as the urease inhibitor for the study. Application of Limus coated NCU led to a 12.5%
increase in yield and 19.8% decrease in nitrous oxide emissions (Fig).
Nitrous oxide emissions and grain yield under urease inhibitor coated neem coated urea
4.8.7 Effect of elevated carbon dioxide and temperature on wheat crop
An experiment was conducted growing wheat varieties HD 2936 and HD 3086 inside the Open Top Chamber (OTC) under ambient (400 ppm) and elevated CO2 level (550 ± 25 ppm and two temperature levels; chamber control and elevated (+2°C). Results showed that straw weight increased under elevated CO2 and high temperature treatment but grain yield was reduceddue to increased spikelet sterility under elevated CO2 and high temperature. Spikelet sterility was more in control treatment as compared to NCU and Limus coated urea applied treatments. Total N of soil was reduced in elevated CO2 and temperature treatment. Total soil N in Limus coated urea applied treatment was more than NCU applied treatment might be due to reduced N loss in Limus coated urea compared to NCU applied treatments.
Spikelet sterility in wheat varieties under elevated CO2 and high temperature
4.8.8 Evaluation of manure potential of phycoremediated algal biomass on baby corn and spinach
In the present study, the microalgae Chlorella minutissima was selected for phycoremediation. C.
minutissima reduced nitrate, ammonium, phosphate, and potassium content in sewage wastewater by 89, 48.2, 67.4 and 66.3 %, respectively. The reduction in BOD, COD and TDS was 93.2, 80.5and 94.3%, respectively within 15 days of inoculation. In a field study, the application of 100% N dose by algal biomass gave economic yield of spinach and baby corn higher or equivalent to yield obtained in urea treatment.
The soil supplied with 100% N by algae biomass (C.
minutissima) significantly increased the dehydrogenase activity in spinach grown soil and the nitrate reductase in baby corn grown soil. Therefore, it can be that inferred phycoremediation coupled with manure production from algae biomass can be a sustainable practice for waste water treatment and to improve the soil quality.
4.8.9 Emission of air pollutants from crop residue burning
Based on remote sensing using satellite data 59668 and 9196 burning events were detected in states of Punjab and Haryana, respectively between Sept. 30, 2018 and Nov. 29, 2018. Based on satellite data in Punjab alone approximately 11.85 million tons of rice crop residue was burned on farms whereas in Haryana it was 1.67 million tons. Burning of rice residue resulted in emission of 18.40 million tons of GHG, 1.31 million tons of other gaseous air pollutants and 0.2 million tons of particulate matter in Punjab and 2.6 million tons of GHG, 0.18 million tons of other gaseous air pollutants and 0.03 million tons of particulate matter in Haryana.
4.4.10 Heavy metals contamination and risk assessment in marketable vegetables in Delhi region
Based on the study conducted in Delhi region at some selected site, the mean concentrations of the selected metals in soil varied over a wide range with decreasing order of Pb> Hg > Cr > Cd > As. The accumulation of heavy metals in vegetables was within the acceptable limits as given by WHO, except Cd, which showed greater contamination in all vegetables at most of the sites, including cultivated and marketed sites. The uptake of the selected metals in vegetables was found below the permissible limit except Cd. The maximum daily intake of metals (DIM) with vegetable consumption was higher for Pb and low for Hg. The results showed that the Hazard Quotient (HQ) for leafy and root vegetables was higher than the safe limits in the case of As at most of the sites. The hazard index (HI) and metal pollution index (MPI) were found higher for spinach compared to other vegetables. As and Pb were found to be potential metals having harmful health
hazards in target hazard quotient (THQ) at all the sites.
4.8.11 Effect of NO
2and SO
2pollution on growth of vegetable crops
An experiment was conducted to study the effect of elevated level of NO2 on plant growth attributes and nitrogen nutrition of the field grown carrot, spinach, tomato, mustard and wheat. The crops, at 30 day stage of growth were exposed to NO2 in specially designed plastic enclosures at following levels viz., ambient (25- 35 µg m-3, C); ambient + 10-15 µg m-3 (LN) and ambient + 40-50 µg m-3 (HN) daily for 1 hour for 7 continuous days. Percent leaf necrosis on NO2 exposure was highest for spinach followed by tomato and mustard.
LN and HN exposure caused severe reduction in leaf chlorophyll for all crops. NO2 exposure, in general, improved N nutrition except in tomato. The study revealed that spinach is highly susceptible to SO2 and NO2 pollution compared to other crops. Most of the selected crops exhibited capability to utilize SO2 and NO2 for sulphur and nitrogen nutrition, respectively.
In another experiment radio-labeled sulfur (35S) was used to measure the contribution of SO2 pollution towards S nutrition of crops showed significant variation in total and tissue S35 accumulation among the five varieties of carrot viz., Pusa-Meghali; Pusa- Vrishti; Pusa- Rudhira; Pusa-Aashita and Pusa-Kulfi.
Relatively higher 35S levels were recorded in shoot and root of the pink types viz., Meghali and Vristi while least S35 were measured in the white carrot type viz., Pusa-Kulfi. The data shows that the ability of the carrot type to utilize S from SO2 is related to biosynthesis and presence of pigments in the root tissues.
4.8.12 Estimation of surplus rice residue and its bioethanol potential in India
A study was undertaken to quantify the amount of surplus rice crop residue in the country and its bioethanol production potential at district level in three crop growing seasons (kharif, rabi and summer) for all the 662 districts of the country. Of the total rice residue produced, 63% is produced in kharif season, 23% in rabi season and 7% in summer season. After
different usages of by farmers, 19% of the rice residue produced remains unused and is surplus.The season wise surplus biomass is 82% in kharif season and 16.6%
inrabi season.The total annual bio-ethanol production
potential from this surplus rice crop residue is 12.28 million liters. The maximum potential is in the state of Punjab (4.7 ML) followed by Uttar Pradesh (2.1 ML) accounting 52.2%
of the total bioethanol production potential.
Bioethanol production potential of surplus rice residue in different districts of India