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1WELCOME
BIG EVENTS HAPPEN IN
SMALL WORLD
ROLE OF NANOTECHNOLOGY FOR CROP PROTECTION IN HORTICULTURE
Speaker
Girija Kumari, Ch.
ID No. 10468
2
Seminar Incharge
Dr. T. M. Rao
3
Nanotechnology/Nanoscience
Nanotechnology
The design, characterization, production and application of
structures, devices and systems by controlling shape and size
at the nanoscale
British Standards Institution (BSI 2005)
4
Nano scale Nano scale
The term ‘nanotechnology’ is based on the prefix ‘nano’- Greek word
meaning ‘dwarf’
Word ‘nano’ means 10 ⁹ or one billionth part of a metreˉ
1 nanometre= one billionth (10 ⁹) of metreˉ
Size range between 1 and 100 nm
The term ‘nanotechnology’ is based on the prefix ‘nano’- Greek word
meaning ‘dwarf’
Word ‘nano’ means 10 ⁹ or one billionth part of a metreˉ
1 nanometre= one billionth (10 ⁹) of metreˉ
Size range between 1 and 100 nm
Nanoscale
5
Richard Feynman, Physicist
“ The father of nanotechnology”
Richard Feynman, Physicist
“ The father of nanotechnology”
“There’s Plenty of Room at the Bottom”
- at American Physical Society meeting at the California Institute of Technology on Dec-29, 1959.
“There’s Plenty of Room at the Bottom”
- at American Physical Society meeting at the California Institute of Technology on Dec-29, 1959.
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Richard Feynman“Adapability to manipulate, control, assemble, produce and
manufacture things at atomic precision”
Norio Taniguchi, Professor
- coined the term “Nanotechnology” (1974)
Norio Taniguchi, Professor
- coined the term “Nanotechnology” (1974)
“Nano-technology’’ - Processing, separation, consolidation and
deformation of materials by one atom or by one molecule.
“Nano-technology’’ - Processing, separation, consolidation and
deformation of materials by one atom or by one molecule.
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Nanotechnology received its greatest momentum with the invention of the scanning tunneling microscope (STM)
It was invented by Gerd K. Binning and Heinrich Rohrer in 1985
What STM does?
It allows imaging solid surfaces with atomic scale resolution. It operates based on tunneling current, which starts to flow when a sharp tip is mounted on a piezoelectric scanner approaches a conducting surface at a distance of about 1 nm. This scanning is recorded and displayed as an image of the surface can be resolved an displayed using STM
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Scanning Tunneling Microscopy
Time Line of Nanotechnology
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~ 2000 Years Ago
Sulfide nanocrystals used by Greeks and Romans to dye hair
~ 1000 Years Ago
Gold nanoparticles of different sizes used to produce different colors in stained glass windows
1959 “There is plenty of room at the bottom” by R. Feynman1974 “Nanotechnology” - Taniguchi uses the term nanotechnology for the first
time
1981 IBM develops Scanning Tunneling Microscope1985 “Buckyball” - Scientists at Rice University and University of Sussex
discover C60
1986 • “Engines of Creation” - First book on nanotechnology by K. Eric Drexler.
• Atomic Force Microscope invented by Binnig, Quate and Gerbe
1989 IBM logo made with individual atoms1991 Carbon nanotube discovered by S. Iijima 1999 “Nanomedicine” – 1st nanomedicine book by R. Freitas 2000 “National Nanotechnology Initiative” launched
(British Standards Institution, 2005)
Physics
BiologyMaterial Science
Medicine Engineering
Bionanoscience
Chemistry
Bionanoscience / Technology
Exploitation of biomaterials, devices or methodologies on the Nanoscale Exploitation of biomaterials, devices or methodologies on the Nanoscale
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Nanoparticles
Nanoparticles are particles between 1 and 100 nanometers in
size
In nanotechnology a particle is defined as a small object that behaves as a whole unit with respect to its transport and properties
Arranged or assembled into ordered layers, or mine layers
Possess distinct physical, biological and chemical properties associated with their atomic strength
(Bhattacharyya et al., 2010)
Nanoparticles are particles between 1 and 100 nanometers in
size
In nanotechnology a particle is defined as a small object that behaves as a whole unit with respect to its transport and properties
Arranged or assembled into ordered layers, or mine layers
Possess distinct physical, biological and chemical properties associated with their atomic strength
(Bhattacharyya et al., 2010)
Nanocarbon
FullereneTubes ConesCarbon blackHornsRodsFoamsNanodiamonds
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Carbon nanotubes
Iijima in 1991
Appeared to be made up of a perfect network of hexagonal graphite rolled up to form a tube
Exhibit unusual photochemical, electronic , thermal and mechanical properties
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Nanoparticles in disease and pest management (Crop Protection)
Biopolymer nanoparticles eg. Chitosan
Metallic nanoparticles eg. Silver nanoparticles
Silica nanoparticles
Copper nanoparticles
Zinc nanoparticles
Nanocomposites eg. Chitosan Silver NP
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ChitosanHas various applications in biology due to its biodegradable and nontoxic properties
chitosan and chitosan nanoparticles are found to be more effective against plant pathogens like Fusarium solani
The chitosan therefore could be formulated and applied as a natural antifungal agent in nanoparticles form to enhance its antifungal activity (Ing et al., 2012)
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Mode of action of chitosan against fungi can be explained by following mechanisms:
The positive charge of chitosan interacts with negatively charged phospholipid components of fungi membrane, which in turn alter cell permeability of plasma membrane and causes the leakage of cellular contents, which consequently leads to death of the cell (García-Rincón et al., 2010)
Chitosan chelates with metal ions, which has been implicated as a possible mode of antimicrobial action (Rabea et al., 2003). On binding to trace elements, it interrupts normal growth of fungi by making the essential nutrients unavailable for its development (Roller and Covill, 1999).
It is suggested that chitosan could penetrate fungal cell wall and bind to its DNA and inhibit the synthesis of mRNA and, in turn, affect the production of essential proteins and enzymes (Sudarshan et al. , 1992; Kong et al., 2010)
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Metallic nanoparticles
Metallic nanoparticles ( Ag, Zn, Cu, Si) possess unique chemical and
physical properties, small size, huge surface to volume ratio, structural
stability and strong affinity to their targets (Kumar et al., 2010)
These can be used as new antimicrobial agents and an alternative to
synthetic fungicide to delay or inhibit the growth of many pathogens
species because of its multiple mode of inhibition
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Silver nanoparticles
Silver has been used as an antimicrobial agent since ancient civilizations; it has been used extensively due to its broadspectrum and multiple modes of antimicrobial activity (Wei et al., 2009)
Silver exhibits higher toxicity to microorganism and lower toxicity to mammalian cells
The application of silver nanoparticles as antimicrobial agents is because of its economical production and multiple modes of inhibitory action to microorganisms (Clement and Jarrett, 1994)
Its specific antimicrobial mechanisms are still unclear
20
Ag acts as plant-growth stimulator and reduces unwanted microorganisms in soils and hydroponics systems (Sharma et al., 2012)
Silver in ionic or nanoparticle forms has a high antimicrobial activity and is therefore widely used for various sterilization purposes (Park et al. , 2006)
Some studies found that inhibition of fungal pathogens with silver nanoparticles is concentration dependent and also on type of silver nanoparticles used
Cont........
21
Silica nanoparticles
Silicon (Si) increases disease resistance and stress resistance in plants (Brecht et al., 2004)
It also stimulates the physiological activity and growth of plants (Carver et al., 1998)
Torney et al. (2007) used honeycomb mesoporous silica nanoparticle (MSN) system with 3nm pores to deliver DNA and chemicals into plant cells and intact leaves
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Copper nanoparticles
Copper-based fungicides produce highly reactive hydroxyl radicals which can damage lipids, proteins, DNA, and other biomolecules
It plays an important role in disease prevention and treatment of large variety of plants (Borkow and Gabbay, 2005)
Because of its bio-compatibility, these nanohydrogels are included as a new generation of copper-based bio-pesticides and it could also be developed into an efficient delivery system for copper based fungicides for plant protection (Brunel et al., 2013)
Complexation of copper with chitosan nanogel was shown to have strong synergistic effect between chitos an and copper in inhibiting the growth of phytopathogenic fungus Fusarium graminearum
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Zinc nanoparticles
Zinc oxide nanoparticles (ZnO NPs) could be used as an effective fungicide in agricultural and food safety applications
Mechanism of action of zinc nitrate derived nano-ZnO on important fungal pathogen Aspergillus fumigatus showed hydroxyl and superoxide radicals mediated fungal cellwall deformity and death due to high energy transfer (Prasun Patra and Goswami,2012)
ZnO nanoparticles can cause deformation of fungal hyphae and prevent the conidiophores and conidial development which ultimately leads to the death of fungal hyphae
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Nanoparticles for pest management
Globally insect pests cause a huge crop loss of 14% and plant pathogens cause an estimated loss up to 13% with a value of US $2,000 billion per year (Pimentel,2009)
Nano pesticide formulations increase the solubility of poorly soluble active ingredient and helps in releasing the active ingredient slowly
Nanoparticles are loaded with pesticides and released slowly based on environmental trigger (Lauterwasser, 2005)
Rotenone, a water-insoluble botanical insecticide used to control aphids, thrips , acari from decades , however its effective utilization has limited due to its poor water solubility, stability, degradation and isomerization when exposed to sunlight
Nanosilica showed 100% mortality against insect pests whereas nanosulfur inhibited the sporulation and growth of fungi (Goswami et al., 2010)
(Royal Society and Royal Academy of Engineering, 2004)25
METHODS OF NANOPARTICLE PRODUCTION
(Royal Society and Royal Academy of Engineering, 2004)26
TOP DOWN APPROACH
(Royal Society and Royal Academy of Engineering, 2004)27
BOTTOM UP APPORAOCH
28
1 m
1 m
1 m
Each edge is 1 m Each edge is 0.1 m, but there are 1000
cube
Volume (in cubic mts ) = 1m x 1m x 1m =1m³
Surface area (in sq. m) = (1m x 1m ) x 6 sides
= 6 sq. m
Volume = (0.1 x 0.1 x 0.1) x 1000 cubes = 1m³
Surface area = (0.1 x 0.1) x 6 sides x 1000 = 60 sq.m
Mode of action of nano particles
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Dendrimers
Quantumdots
Nanosensors
FullerenesCarbon Nanotubes
Nano Chips
C60 Cadmium selinade
3D
macromolecules
Sequence nanoscale
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Tools of Nanotechnology
C60
Applications In Agriculture
31 (Mahendra et al., 2012)
32Applications of nanotechnology in crop protection and plant nutrition
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CASE STUDY : 1
Antifungal effectiveness of nanosilver colloid against rose
powdery mildew in greenhousesKim et al., 2008
Solid State Phenomena Vol. 135 , pp 15-18
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IntroductionPowdery mildew, caused by Sphaerotheca pannosa var. rosae, is one of the most common and widespread fungal diseases of greenhouse and outdoor roses which reduces flower production and causes weakening of the plants
It mainly appear first on the under surface of young leaves in early summer and the infection spreads to stems, shoots and buds
Silver have long been known to have strong antimicrobial activity and AgNP because of their specific surface area have high activity than their bulk siver metal
Nanosilver colloid that is a well-dispersed and stabilized silver nanoparticle solution will be more adhesive on bacteria and fungus and so have enhanced antibacterial activity
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Objective of the study
To examine the effectiveness of nanosilver colloid as new fungicide against rose powdery mildew in greenhouses
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Material and Methods
31.5 g of 99.8 % AgNO3, was dissolved in 3.7 l distilled water and 40g PVP as stabilizer was added
1g of 98.0 % NaBH4, as reducing agent was dissolved in distilled water of 0.2 l and this solution was slowly dropped in silver ion/PVP solution under sonication
After adding 28.5 g quaternary ammonium chloride (Cluster Instruments Co., 80 %) as another stabilizer was dissolved and vigorously stirred for 1 h
The particle size of nanosilver and UV-visible spectrum of nanosilver colloidal solutions was characterized by Transmission electron microscopy (TEM) and UV spectrometer, respectively
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The antifungal effects of nanosilver solution carried out at a commercial greenhouse (Sung-Ju Farm), located at SungJu (Gyeongsangbuk-Do, Korea), an important area for cut rose production
Rose plants, belonging to the 'Suncity' cultivar, were grown according to the cultural practices normally adopted by local growers
The nanosilver solution of 500 kg with concentration of 10 ppm was sprayed at large area of 3306 m2 infected by the rose powdery mildew
Cont....
The antifungal effects wereobserved by an optical microscope
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Results and discussion
TEM images of the nanosilver
in colloidal solution of 1000 ppm
Average size was 1.5 nm with size
distribution of 1-5 nm
In addition the images showed that
nanosilver particles were densely and well
dispersed in the colloidal solution
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Absorption spectra of a nanosilver colloidal solution afterdilution; (a) only stabilizers (b) 1 ppm, (c) 5 ppm.
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Photographs of rose effected with powdery mildew
before treatment immediately after treatment 2 days after
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Photographs of leaves with powdery mildew
Before treatment a week after treatment
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Before treatment
Optical microscope (80 magnification) images of powdery mildew on leaf of rose
week after treatment
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Conclusion of the study
The double-capsulized nanosilver showed high dispersity and stability
The photographic results showed that the effects of nanosilver colloidal solution against rose powdery mildew was very high and durable for a week
In addition, the nanosilver did not have phyto-toxicity on the plants cell of leaves, stem and buds of rose plants
As a result, well dispersive and stabilized nanosilver could be recommended as new fungicide for powdery mildew
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DNA-tagged nano gold: A New Tool For The Control Of The Spodoptera
litura Fab. (Chakravarthy et al., 2012)
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CASE STUDY : 2
African Journal of Biotechnology Vol. 11(38), pp. 9295-9301, 10 May, 2012
46
Introduction
Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae) is an extremely serious pest, the larvae of which can defoliate many economically important crops cutting across over 40 families
Polyphagous, voracious feeder and very prolific pest
The use of insecticides in agricultural fields leads to an ecological imbalance in nature and thus in some countries including India, several insecticides have been banned (Yadav, 2010)
A very recent approach to the control of insect pests is the use of DNA-tagged nano particles
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To examine the potential of DNA-tagged nano particles for the control of Spodoptera litura
Objective of the study
48
Material and Methods
A solution of HAuCl4 dissolved in 20 ml of distilled water was used as the solvent for the preparation of gold (Au) nanoparticle
The solution was continuously stirred in a bath at 110°C for an hour and then quickly treated with C6H5Na3O7
The Au nanoparticle solution was then further reacted with an aqueous solution of calf-thymus DNA-sodium salt to obtain DNA tagged Au nanoparticles
To determine the virulence/lethal concentration of DNA-tagged nano particle solution, serial dilutions of the nano particle solution ranging from 200, 300, 400 to 500 ppm were prepared
10 μl of the suspension was dispensed on the semi-synthetic chickpea (Cicer arietinum) based diet filled into 5 ml glass vials
49
Second instar larvae of S. litura of uniform age and size were released onto the diet 20 min after surface treatment with DNA-tagged gold nanoparticles, at all four concentrations viz., 200, 300, 400 and 500 ppm
A control diet was maintained where chickpea based semi-synthetic diet was applied and used without DNA-tagged gold nanoparticles
Observations of larval settlement on the diet were taken from first day onwards
Larval mortality was recorded from 3rd till 10th day at 24 h interval. Each treatment was replicated thrice
Cont.....
50
Results and discussion
As the concentration and days after treatment increased, the larval
mortality of 2nd instar S. litura larvae also increased. The maximum
mortality of 30.0 (33.2), 57.5 (49.6) and 75.0 (60.5) was obtained at 500
ppm on 3rd, 4th and 5th day, respectively
There were statistically significant differences between the treatments
and the days after treatment required for 50% mortality of the larvae
At the highest concentration (500 ppm) of the DNA-tagged gold nano
particle, feeding was reduced, larvae turned sluggish and were unable
to orientate towards the source
Treatment (PPM) Percentage of larval mortality days after treatment
3rd 4th 5th
200 10.0 (16.0)b 27.5 (31.4)c 35.0 (36.0)b
300 22.5 (28.2)a 42.5(40.7)b 62.5(52.3)a
400 25.0(29.7)a 55.0 (47.9)ab 72.5 (58.6)a
500 30.0 (33.2)a 57.5 (49.6) a 75.0(60.6)a
Control 0.0 (0.6)c 0.0 (0.6)d 0.0 (0.6)c
SEM ± 2.92 2.87 3.05
CD at 5 % 8.81 8.66 9.20
51 (Chakravarthy et al., 2012)(Chakravarthy et al., 2012)
Effect Of Different Concentrations Of DNA-tagged With Nano Particle On 2nd Instar S. litura, Three,
Fourth And Fifth Days After Treatment
52
Effect of different concentrations of DNA-tagged gold nanoparticles on 2nd instar S. litura larvae
53
2nd instar S. litura larva at three days after treatment
2nd instar S. litura larva four days after treatment
The larvae ceased active movement, the skin and entire body became stiff and hard and oozing of the body content (lysis)
The body became swollen, pulpy and fragile. It attained almost a ‘C’- shape and body turned dark brown
2nd instar S. litura larva at four days after treatment
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2nd instar S. litura larva at five days after treatment
2nd instar S. litura larva six days after treatment
The larvae showed premature molting in and half of the body became discoloured (fleshy white) and the other half turned brown
The larvae attained pupal shape, all the internal contents oozed out, and eventually death occurred
55
2nd instar S. litura larva seven days after treatment
Control
The dead larvae turned black
56
Conclusion of the study
This study clearly demonstrates that DNA-tagged gold nanoparticle has a devastating effect on the larval tissue of S. Litura and would therefore be a useful component of an integrated pest management strategy
Metal nano-particles could be a better alternative to synthetic insecticides, in addition to being a toxicant that inhibits biological and physiological systems of insects
This experiments clearly established that the DNA tagged gold nano particle should be tested at concentrations higher than 500 ppm to determine the effective dose resulting in 50% larval mortality
Subsequent to the laboratory tests on S. litura, field tests on a small scale need to be initiated
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Other Applications Of Nanotechnology
57
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According to Mariya Khodakovskaya, a plant biologist, and Alexandru Biris, a nanotechnologist founded a technique used carbon nanotubes to encourage fast and early germination of tomato plants
Tomato seeds were planted, some with a growth medium containing carbon nanotubes, and some without nanotubes in the growth medium
It took only three days for more than 30% of the nanotube tomato seeds to begin sprouting. In that time, none of the non-treated seeds had even germinated
In fact, it took 12 days for 32% of the tomato seeds without nanotube help to germinate
After four weeks, the researchers noticed that the tomato plants that had been treated with carbon nanotubes had two times the biomass and two times the height of their non-treated counterparts. The current theory is that the nanotubes penetrate the seed coat of the tomato seeds, allowing water to more rapidly penetrate the seeds and boost their development
http://phys.org/news174066714.html#jcp
Other Applications of nanotechnology (carbon nanotubes)
Nanotechnology for seed germination
59
Interestingly, the root systems were similar in all of the plants, so the nanotubes did not change the way the roots established themselves
Another issue is that the nanotubes seem to be causing abnormally long internodes, and that might affect the ultimate outcome regarding the viability of mature plantsThe mechanism of ionic interactions with the CNT surface (Miskovic 2008) implies that redox type changes of the nutrient ion of a given oxidation state might take place with the MWCNTs in the medium.
There is a potential for the utilization of CNTs for optimizing water transport in arid-zone agriculture and Horticulture and of improving crop biomass yields
http://phys.org/news174066714.html#jcp
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Nanoparticles in post-harvest disease management
Chitosan, a deacetylated derivative of chitin, is found to be very effective
in reducing postharvest decay of fruit and vegetables (Liu et al. , 2007)
Chitosan/nanosilica hybrid film, extended shelf life, reduced browning
index, retarded weight loss and inhibited the increase of malondialdehyde
amount and polyphenoloxidase activity in fresh longan fruit (Shi et al.
2013)
Pulsing of nano silver (with 2.5 nm diameters) on cut gerbera (Gerbera
jamesonii) cv. Ruikou flowers for 24 h with 5 mg/L nano solution extended
vase life and inhibited the bacteria growth in vase solution for initial 2 days
when observed in vitro under microscope (Liu et al. 2009)
Biological toxicity Environmental toxicity
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Nanotoxicity
62
Conclusion
Nanoparticles are biodegradable and target specific, so they can be
successfully employed in production of nanocapsules for delivery of
fungicides, pesticides, fertilizers, and other agrochemicals
Nanotechnology will revolutionize agriculture including crop protection
in the near future
Over the next two decades, the green and golden revolutions would be
accelerated by means of nanotechnology
63
Future prospects
More studies are needed to explore the mode of action of NPs, their
interaction with biomolecules, and their impact on the regulation of gene
expressions in plants
Research on nanoparticles with respect to crop protection should be
geared towards introduction of faster and ecofriendly nanoformulations in
future
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Thank you