flooding, deep ploughing & solarisation
TRANSCRIPT
FLOODING, DEEP PLOUGHING & SOLARISATION
AS A
TECHNIQUE TO MANAGE THE PEST
BY : JAYANT YADAV, CCSHAU, HISAR, HARYANA
FLOODING
It is also the ancient method of using pest of field crops.
The process of keeping the land submerged in water which decrease
the oxygen content of soil and kills the pest by asphyxiation is called
flooding.
Flooding can be used in crop protection since it reduces number as
well as number of pest and nematode in the soil.
Flooding in field
Pest management using flooding
Insect Pest
Flooding of potato fields for 7-10 days , reduce the population of white grub.
Alternate wetting and drying at 10 days interval starting from 35 days after
transplanting drastically reduced brown plant hopper and white backed plant
hopper incidence in continuous standing water.
Flooding of fields also kills root grubs ,termites and soil born plant pathogen.
Flooding followed by tillage, is more effective for suppressing stem borer
population.
Flooding at the time of pupation reduces the survival of H. armigera.
Flooding has strong effect on most soil pest including white grub, mole
cricket, termites and ants.
The cotton bollworm can be shaken off by dragging a rope over the plants and
throwing them into standing water, where it gets killed.
Cont……..
Continuous flooding also reduces the incidence of gall
midge .
Flooding is also effective if used in combination with
crop rotation.
Flooding also eliminates the sclerotia of Sclerotinia
sclerotiorum.
Cont……..
Deep Ploughing
Deep ploughing is defined as the ploughing of field across the slop during hot summer
with the help of specialized tools with primary objective of opening of soil crust and
simultaneously overturning of soil underneath to disinfect it with the help of sun rays.
Ploughing or hoeing helps to expose stages of soil inhabiting pest to such sun heat or to
predatory bird.
Two or three deep ploughings with soil turning device, in hot summer months expose
the pest in soil and infected tissue to solar heat and dehydration.
Efficacy of ploughing can be increased by polythene mulching to trap and retain more
heat than exposed soil.
Deep Ploughing
Insect Control - Deep Ploughing
Deep ploughing has been recommended as a strategy to kill
insect pest that live in top 20 cm of soil.
Deep ploughing immediately after harvest of wheat crop in
April –May is helpful in exposing the resting grubs of rice
root weevil to their natural enemies like birds and to action of
sun.
Raking up and hoeing of soil around melon plant, mango and
other fruit trees serve to destroy pupae of fruit flies.
Light earthing at early stage of sugarcane crop during May-June is
helpful in checking the shoot borer.
Fall ploughing is often helpful in reducing the overwintering
population of H.armigera.
It is also helpful in minimizing the infestation of armyworm in
cereal crops, white grubs attacking groundnut and chilli, pupae of
hairy caterpillar attacking groundnut and green gram.
Other Benefits of Deep Ploughing
Deep ploughing improve soil structure due to alternate
drying and wetting.
A lot of harmful bacteria spores and fungal microbes die
due to exposition to heat of summer.
Deep ploughing and overturning uproot the weeds .So the
competition between crop and weed also reduced for same
nutrient and productivity increased.
Soil Solarisation
Soil solarisation is an environmentally friendly method of using solar
power for controlling pest such as soil born plant pathogen including
fungi bacteria nematode and insect along with weed seeds and
seedling in soil by mulching the soil and covering it with trap usually
with transparent polythene cover, to trap soil energy .
Soil solarisation is a simple, safe, and effective alternative to the
toxic, costly soil pesticides and the lengthy crop rotations now needed
to control many damaging soil pests.
Involves covering the soil with transparent plastic
sheeting during an appropriate summer fallow period.
It captures solar energy and raises the temperatures in
the soil to levels lethal to many soill borne pests.
It’s a pre-plant method for disinfecting soil for control
of soil borne insect, pathogen and weeds.
The major commercial use of solarization has been in
regions with high solar radiation and high temperatures
Soil Solarisation
Procedure of soil solarisation
The soil to be solarised must be worked up to seed-bed condition—that
is, cultivated until it's loose and friable with no large clods or other
debris on the soil surface..
Make sure moisture levels are adequate for working the soil before
laying the plastic tarp.
If the soil is dry, water the areas to be solarized before laying the tarp,
because most soil pests are more sensitive to high temperatures in wet
soil than in dry soil.
There are four factors that need to be remembered while
applying soil solarization
1. Transparent, not black, polyethylene plastic should be used, as
this transmits most of the solar radiation.
2. Solarisation should be carried out during periods of high
temperature and intense solar radiation.
3. The thinnest plastic possible should be used, as it is both
cheaper and somewhat more effective in heating.
4. The plastic sheeting should be kept in place for as long as
possible
Use a clear, UV-stabilized plastic (polyethylene or polyvinyl chloride)
trap or sheeting 0.5 to 4 mils thick.
The edges of the sheets must be buried to a depth of 5 or 6 inches in the
soil to prevent blowing or tearing of the tarp by the wind.
White or black plastic usually does not transmit enough solar radiation
to raise soil temperatures to lethal levels for many soil pests.
Temperature inside the plastic covering rise to 130C higher than outside
temperature which is very lethal to insect-pest and weeds.
Cont……..
Long, hot and sunny days are needed to reach the soil
temperatures required to kill soil borne pests and weed seed.
The longer the soil is heated, the better and deeper the control of
all soil pests and weeds will be.
For effective soil solarisation, a 6 to 8 week traping period may be
needed to ensure good pest control.
However depending upon the geographic location, solarisation
may also be effective in May, August and September.
Cont……..
Pest and disease control using soil solarization
Soil solarisation is one of the effective way of suppressing the
larvae of white grub, cutworm, hairycaterpillar as they gets killed
inside the soil due to high temperature.
Soil solarisation helps in reducing root knot disease by
suppressing the nematode population by 66% in nursery with in
15days.
Other benefits:
Plants grown in solarised potting mix soon after
treatment have often benefited from improved seed
germination, better stand establishment, improved
plant height, early crop maturity and increased yield
(both fresh and dry weights).
Cont……..