this ppt contains impact of climate on disease of plants.

1. @ ML Murugan

2.  Temperature
 Humidity and
precipitation
 Light
 Wind
@ ML Murugan

3.  Several research studies have indicated that
many crop plants may not be infected under
certain temp conditions.
 It has been found in diff. rice varieties
 Rice blast (night temp at 26c)
 Temp variation ..though the cooling of leaves by
drops has not shown to have any effect on the
parasitic diseases.
@ ML Murugan

4.  Various fungal disease are influenced by
temp,therefore,the development of disease stops
under extremely low and high temperature
conditions
@ ML Murugan

5.  It is an important role in the incidence of pests and
diseases.
 Soil moisture content has great influence on the
severity of soil borne diseases and the depth of
the existence of pest living in the soil.
 Cooling of the leaves at night is caused by the
emission of infra-red radiation from the leaves.
 Most parasitic fungi of foliage are believed
@ ML Murugan

6.  To require free water for sore germination.
 Some fungi can be germinate in h.humidity in the
absence of free water.
@ ML Murugan

7.  Full day light reduces the germination or growth of
plant pathogens but many fungi germinate better
in light of moderate intensity than in complete
darkness.(powdery mildew)
 On the other hand,the germination of certain rusts
may be much greater in darkness than in light.
@ ML Murugan

8.  It has direct & indirect effect on the crop
plants.cold and hot winds can cause chilling and
sunburn,where as,strong winds can cause soil
erosion,high desiccation and mechanical injuries
to the plants.
 Wind act as carrier of insects from place to place
and transport many diseases through the insects.
@ ML Murugan

9.  It is the period in which infection has taken place
but symptoms do not occur.
 Temperature influences the latent period.
It depends on:
 nature of pathogen
 type of host
 environmental conditions
@ ML Murugan

10.  It is the period from appearance of symptoms
to the release of spores. It is also influenced by
weather variables. Eg:infection period of peanut
rust is influenced by temperature.
@ ML Murugan

11.  Climate conditions are favourable for the wheat
rust to servive in the himalayan region during
summer season on the host plant of
barberry.nepal(source region of rust-during
summer)
 Nilgiri hills in south india are the source region of
wheat rust.
@ ML Murugan

12.  Wheat rust appears in in north-west india when
there exist favourable weather conditions.
 It can be divided into three types
@ ML Murugan

13.  Due to low temperature(confined to northern parts
of India).the weather conditions become
favourable for the appearance of rust by the end
of January.
 Air temperature between(9-13∘c)
 R.humidity more than 70%
 There must exist partly cloudy conditions.
@ ML Murugan

14.  It can survive over a wide rage of temperature.
(northern&southern hills are the regions).it
appears in punjab during the month of february.
 Air temp between 15-20°c
 R.humidity should be more than 70%
 Intermittent cloudiness must exist in the end of
january or 1st week of february.
@ ML Murugan

15.  It can survive in the northen hills throughout the
summer season.(source is nilgiri hills)
 End of february –mid march only it can appears.
 Mean air temperature between 16-27°c
 R.humidity should be 70%
 There should be excessive dew
@ ML Murugan

16.  During winter season, western disturbances cause
cloudiness,rains,dew and fog over north
india.when It become favourable ,late blight of
potato appears.
 During summer season,incidense of late blight of
potato is common in hilly regions.
@ ML Murugan

17.  The weather conditions which are favourable for
the incidence of many rice diseases.
@ ML Murugan

18.  Min temp. should be less than 26°c
 R.humidity should be more than 90%.
 If these conditions prevail during the period of
seedling,tillering and ear emergence, then the disease is
likely to appear.
@ ML Murugan

19.  Temp. range between 19-37°c in summer,
 17-26°c in winter season.
 High relative humidity should persist.
 Irrigated conditions is more susceptible to this disease.
@ ML Murugan

20.  There should be excessive rainfall during the
reproductive period.
 High humidity & lower temperature should persist.
@ ML Murugan

21.  Temperature should between 30.4-32.7°c
 Relative humidity between 86-93 %
 Sunshine hours should range between 3.3-7.8 hrs per
day
 These conditions adversely affect the spread of the
disease.
@ ML Murugan

22.  Leaf spot it is an important disease of groundnut.
It may be two types early leaf spot and late leaf
spot.
 This disease is more common in those areas,
where groundnut cropping system is existing.
 Early leaf spot - can appear few weeks of
sowing(damage 10-15%)
@ ML Murugan

23.  Leaf wetness is also one of the causes of these
disease.(higher in kharif season)due to dew, fog
and rainfall
 Favorable temp(22-35⁰c)
@ ML Murugan

24.  It may appear at any phonological stage of the
crop. it is influenced by temperature conditions,
leaf wetness and high humidity.
 Fav.conditions(temperature at 24c,r.humidity
87%,intermittent rain fall)
@ ML Murugan

25.  Temperature around 20-25c
 High and prolonged rainfall
 Intermittent cloudiness & dew
 Strong winds are favourable for disease spread
@ ML Murugan

26.  It appears at flowering and podding stage in the
form of pycinia and aecia.it germinates at 17-22c
and infect other plants forming either
 Secondary aecia or uredia depending upon
prevalent temperature of 25c
@ ML Murugan

27.  It appers at the larger stage of the crop during
rainy season.intermittenet rains are favourable for
the disease development.
 Tempv22.5-23.5c
 R.humidity between 77-86%
 Sunshine more than 5 hrs
 Should me more no. of rainy days.
@ ML Murugan

28.  temp at 20-25c
 R.Humidity should be around 92% during rainy
seasons.
 Cloudy weather.
@ ML Murugan

29.  IPCC, 1996a. Climate Change 1995: The Science
of Climate Change.
@ ML Murugan

30.  Kattenberg A., Maskell, K. (Eds.), Contribution of
Working Group
 I to the Second Assessment Report of the
Intergovernmental Panel
 on Climate Change. Cambridge University Press,
Cambridgeetc.
@ ML Murugan

31. @ ML Murugan