There is little bit variation in the years of published work and this ppt contain brief explanation.

1. History of Host Plant
Resistance

2. Haven (1772)
 Haven for the first time the phenomenon of host plant resistance to insect.
 He reported that “undehill” variety of wheat to be resist the attack of hessian fly
Mayetiola destructor in New York.

3. Cont…
 The adult fly is tiny, dark colored insect. Females lay
eggs on seedling leaves, which hatch in 3 – 7 days,
move down the stem and reside in the grooves of leaf
sheath and stem.
 Larvae are the only stage that damage wheat , adult flies
don’t feed. Maggots usually feed on the lower leaves
and stem and reduce plant vigor. Infested plants
become stunted and leaves are thickened with a bluish
green color.
 A single maggot feeding on plant for 3 days can stunt a
younger plant or tiller. Heavily damged plant usually die
in winter.
https://entomology.ca.uky.edu/ef155

4. Cont…
 Hessian fly has caused the severe losses in wheat for
the past 250 years in the Ohio state of America.
 It is not definitely know how the fly has arrived from
Europe. The story is the one that reports that the fly
was found in the vicinity where Howe’s British troops
were encamped.
 It was thought that the Hessian soldier in the British
army brought the pest from the Europe in straw used
for bedding. Thus its name Hessian fly.
https://images.app.goo.gl/PiacAxvPxjoPG27J6

5. Cont…
 The damage was reported in 1770 in the USA and caused shortage of
wheat.
 Then the scientists were started to develop a variety resistant to Hessian
fly.
 The earliest record of observation on hessian fly resistance in wheat was
made by Issac Underhill.
 The resistant wheat was described as hard stemmed which was
subsequently given the name of underhill.

6. Lindy Ley (1831)
 He reported insect resistance in apple variety “Winter Majetin” resistant to
woolly apple aphid Eriosoma lanigerum in England.
 The aphid native to North America and it is now distributed throughout apple
growing region of the world.
 The woolly apple aphid may occur on the above ground portion or roots of
the apple tree.
 The galls form on the root system, increase in size year by year and site where
fungi can attack.

7. Cont…
 Woolly aphids are tiny burrowing insects with a
protective white fluffy cottony covering.
 Severe infestations look as there is cotton wool on the
braches of the tree.
 They suck sap from young branches, buds, leaves,
even roots and can quickly weaken the tree.
 Mature tree usually suffer little damage from the root
infestation but the root infestation are very damaging
to young trees.
https://entomology.ca.uky.edu/ef219

8. Cont…
 Mass woolly aphid infection in the late 19th and early 20th century promoted the use of
Northern Spy as a rootstock.
 This American apple variety (Northern Spy) was resistant to woolly apple aphid.
 Most scion cultivars were grafted on rootstock of Northern Spy.
 Apple variety “Northern Spy” grown for its fruit in eastern Canada, USA, Australia, parts
of NewZeland and to some extend in South Africa never suffered damage by this pest.

9. T. V. Munson and Francios Baco
(1890s)
 Grape phylloxera is an insect pest of grapevine worldwide.
 It produces galls on the leaf or roots in the Viteus vitifoliae
in Europe.
 Root galls cause stunting or death of European varieties of
grape vines.
 By the mid 19th century, viticulture played a major role in
France economic development.
 However all this changed with the arrival of devastating
insect around 1864.
https://images.app.goo.gl/mGzHYXaD2yaTnLHt7

10. Cont…
 The appearance in France of Phylloxera “an insect
that originated in North America”, lives on the vine
root system and kill the plants.
 France vineyard was collapsed and decreased the
wine production.
 Unlike European vine species, American vine species
were resistant.
 As a consequence French wine production was
declined by about 70% in the 1870s and 1880s.
 France moved from being the world’s leading wine
exporter to a wine importing country in less than a
decade.
https://images.app.goo.gl/PHpF7d2wqrFp211fA

11. Cont…
 By 1890, average annual wine production in France had fallen to 30 million
hectoliters while consumption remained at about 45 million hectoliters.
 To fill this gap, France followed a strategy with four components.
 To make vineyard resistance to phylloxera
 To increase wine import especially from Italy and Spain
 To import dried grapes (used vine formation in France)
 Wine production in North African colonies.

12. Cont…
 It took twenty years to understand why vines were dying and to make
vineyard resistant to phylloxera.
 French vineyard has been destroyed a few decades earlier by Odium
(Powdery mildew).
 The discovery of sulfur to tackle the odium vine disease allowed France to
rapidly recover its vine production level.
 This stimulated wine growers to fight with phylloxera with the same means
but unsuccessfully.

13. Cont…
 In the search for a cure, two groups of scientist oppose each other, “The
chemist” and “The Americanist”
 The first group advocated chemical treatment into vineyard.
 The second group advocate the problem was solved by only Phylloxera
resistant American wine.
 The roots of the American vine excude a sticky sap that repels pest by
clogging its mouth when it tries to feed.
 By 1880s, new type of phylloxera resistance vines had bee developed by
using two ways……..

14. Cont…
 The first solution was developed by Charles valentine in collaboration with
J. E. Planchon and promoted by T. V. Munson involved grafting European
vine sp. scion on to the root of resistance American vine sp.
 The second solution was developed by Francios Baco and was consisted of
two or more varieties of different vine species (Hybrid).
 Hybrid were the result of genetic crosses between European and American
vine species.

15. Parnell (1935)
 In Africa, found only single cotton plant not affected by jassid.
 The importance of jassid pest of cultivated cotton in those region of
Africa where cotton grows under rainfall.
 The most satisfactory method to control this pest on large scale lie in the
use of resistant varieties.
 The breeding of the resistant type suited to south African condition has
been successfully carried out at Barberton.

16. Cont…
 This breeding work has greatly facilitated by an
observed relationship between hairiness of the plant
and resistance to the infestation.
 The hairier the plant the greater being its resistance.
Hussain (1940)
 They stated as all resistant varieties of cotton are
hairy.
Lal (1941)
 He referred as to pubescence of leaves as a
protective factor against jassid.
https://images.app.goo.gl/rTsBV1tkYYdwwo4f8

17. Monsanto (1995)
 The technology for managing insect pests was approved for commercialization
in the United States by the U.S. Environment Protection Agency in October 1995.
 This technology is now available from several seed company in the USA as well
as in many other cotton growing countries around the world.
 Monsanto scientists produced transgenic plant (Bt Cotton).

18. Cont…
 Bt cotton contain one or more foreign genes derived from the soil
dwelling bacterium (Bacillus thuringiensis).
 The insertion of the genes from Bacillus thuringiensis cause cotton plant
cells to produce crystal insecticidal proteins often referred to as Cry
protein (Cry1A, Cry4…….).
 The insecticidal proteins are effective in killing some of the most injurious
caterpillar of cotton such as bollworm and tobacco budworm.
 Helicoverpa armigera
 pectinophora gossypiella

19. Cont…
 When the insect eats these Cry proteins its own
digestive enzymes activate the toxic form of the
protein.
 Cry proteins bind to specific receptors on the
intestinal wall and rupture the midgut cells.
 Susceptible insects stop feeding within a few hours
after taking their first bite and if they have eaten
enough toxin die within 2-3 days.
https://images.app.goo.gl/KGGe8t7TMdYDRw45A

20. Reference
 https://entomology.ca.uky.edu/ef219
 http://treefruit.wsu.edu/crop-protection/opm/woolly-apple-aphid/
 https://ocj.com/2013/10/hessian-fly-history/
 https://www.slideshare.net/vaishaliparmar2/introductory-to-host-plant-resistance
 https://www.ars.usda.gov/ARSUserFiles/oc/np/btcotton/btcotton.pdf
 https://www.econstor.eu/bitstream/10419/172036/1/870035193.pdf

21. Thank You