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Projects
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1) Exploiting the potential
of halophytes as source of edible oil
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Pakistan is
currently facing the severe shortage of good quality
water for human consumption and for conventional agriculture.
Irrigated land is more susceptible to salinity and it
is estimated that large cultivated areas in Pakistan
are becoming saline. Halophytes can be used as oil-seed
crop on highly saline soils or where available water
is of poor quality. There are reports which indicate
that some of the halophytes have better quality edible
oil in comparison to most commonly used Palm oil in
Pakistan. The seed oil study of different halophytes
showed that the average un-saturation for the fatty
acids in the seed oil was 84 percent, which is favorable
from nutritional point of view. These studies showed
that the oil from the halophyte seeds is of high quality.
However, in selecting such a crop several different
considerations should be taken into account; i) suitability
of the crop in a given ecosystem, ii) quality of the
oil, iii) potential of being used as edible oil, iv)
ease of harvesting, v) oil content, vi) protein meal
quality, vii) quantity of ash present, viii) sustainable
irrigation system, ix) management of cultivated lands,
etc. The use of halophytes from Pakistan as a seed oil
crop seems to be the available alternative.
We are proposing here the use of perennial halophytes
that could be grown once and could be managed for a
very long time without reseeding. This would significantly
save time and efforts to grow them and would make them
economically viable. Fine-tuning of the technology would
be required to address the local environmental constraints.
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2)
Use of Halophytic shrubs as alternate source of cattle
fodder
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Pakistan faces
an acute shortage of meat and dairy products. The demand
is on the increase and the production gains are insufficient
to meet the shortage. In cattle breeding, improper nutrition
produces weak animals which are prone to diseases. Selection
of a suitable breed for particular purpose i.e. milk
or meat production and proper management of the flock
are necessary for optimum production.
Diet and health care are important factors for raising
a good flock. The animals are generally fed a mixture
of dry and green fodder, which are in short supply and
expensive to procure. Wheat / rice straw are generally
the most common dry fodder while corn / sorghum are
major green fodder. All these crops require good land
and good water for their growth. Sweet arable lands
and good quality irrigation water, which are becoming
scarce with time, are needed for producing crops for
human consumption. The pastures and grazing lands hence,
have to rely on rain (unreliable source) and may occupy
less productive areas like salt effected lands where
vegetation changes to more hardy plants species i.e.
halophytes.
While the halophytes may be productive under harsh conditions
of high salt contents of soil, which they manage by
balancing their internal osmotic potential through salt
accumulation in foliage, their consumption by animal
requires proper feeding trials for monitoring the ill
effects, if any, on the animal health. The present project
aims at studying the possibility of decreasing dependence
on traditional dry and green fodder by replacing them
with suitable halophytic plants.
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3) Screening and eco-physiological
studies of halophytic grasses for utilization as forage
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| Soil salinity
and/or sodicity have caused havoc all over the world
rendering vast tracts of agricultural lands unfit for
conventional crops. These salt affected areas could,
however, be utilized for raising cash-crop halophytes
which are well equipped to survive and complete their
life cycle in saline soils. Properly managed irrigation
systems using saline-sodic soils and brackish water
have the potential to sustain and improve crop production
with minimum adverse environmental consequences. The
proposal aims at finding suitable local halophytes and
developing methods for optimizing their growth to be
utilized as cattle fodder to produce meat for local
consumption as well as for export, if feasible. This
would also help in rehabilitation of saline and sodic
lands, improve productivity per unit of water, besides
developing a sustainable fodder crop using saline water
irrigation on lands which at present are lying barren.
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4) Salt-induced oxidative stress,
consequences and possible management
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Salinity is the most important of the
agricultural problems of the semiarid and arid regions
including Pakistan. Furthermore, salt deserts (caused
by drought or a lack of fresh water) and saline inland
basins (caused by the level of saline ground water
rising as a result of leakage of drainage water) are
being created. These degraded areas could be economically
productive if we could understand the physiology of
salt tolerance of both conventional and non-conventional
crops. Abiotic stresses cause the oxidative stress
or enhanced production of reactive oxygen species
(ROS) like OH-, O-2 and H2O2.
These ROS can damage essential membrane lipids as
well as proteins and nucleic acids of cells. Levels
of ROS in plant cells are normally controlled by protective
antioxidant activity. However, under environmental
stresses, like temperature or drought ROS production
can increase and protective antioxidant activity may
then becomes inadequate, which may lead to plant or
seed fatality. Although, a considerable attention
has been paid to this aspect for few decades but all
such investigations are confined to other than saline
stress. Little work has been reported on the oxidant
and antioxidant activities under saline conditions.
We will investigate the role of oxidants, antioxidants
and their enzymes at various stages of the plants
life cycle growing under saline conditions.
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5) Small-scale resource heterogeneity
among halophytes in some coastal communities of Pakistan
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| Salt
marshes and salt deserts are considered as wasteland,
however, such habitats are national assets and harbor
many salt tolerant species with a high economic potential
for increased food and fiber production and of medicinal
importance. Besides, they are a crucial part of the
complex natural ecosystems which they help to sustain.
Currently, all over the world over, the ultimate goal
is the sustainable development of non-conventional crops
and practices to fit the environment. Natural habitats
are being preserved and disturbed communities are restored
in order to preserve the biodiversity. All this can
best be accomplished by understanding the distribution
and eco-physiology of species already adapted to diverse
saline environment. About 100 species of halophytes
are reported along the coastal areas of Pakistan but
little empirical data is available about the current
status of vegetation distribution patterns, soil nutritional
status and the underlying mechanisms influencing vegetation
ecology. In order to achieve these objectives, the following
points will be investigated: 1. Distribution pattern
of coastal halophytic communities along environmental
gradients, 2. The relative importance of various soil
nutrients in the growth and distribution of coastal
communities 3. Categorization of community types with
respect to micro-habitat variation and 4. The eco-physiological
responses (osmo-regulation, osmotic adjustment, photosynthesis)
of selected halophyte communities in different environmental
conditions. |
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| 6)
Stress tolerance in mangroves |
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| Mangroves, distributed
along the coasts of Pakistan, are ecologically and economically
important. They provide breeding ground for crustaceans
and fishes, serve as a sanctuary for migrating birds
and protect the ports of Karachi and Bin Qasim against
siltation. Pollution, lopping by inhabitants and diversion
of river water from irrigation system are causing mass
extinction of some mangrove species. Although, some
of the species have been re-introduced both in the deltaic
and coastal regions recently but, there is a need to
understand mechanisms of their response to salt induced
oxidative stress. The degraded mangrove wetlands could
be rehabilitated and become economically productive
if we could understand their physiology of salt and
oxidative stress. Preliminary investigations have shown
that Avicennia marina is the most salt tolerant
species and Rhizophora mucronata & Ceriops
tagal could tolerate moderate to high salinities
however, scavenging of Reactive Oxygen Species (ROS)
through enzymatic and non-enzymatic pathways including
the role of osmotica are the research areas that need
to be addressed in detail. Although considerable attention
has been paid to such studies on other halophytes and
a few mangrove associates, no work has been reported
on our local species. It is hence proposed to investigate
the role of antioxidant enzymes, osmotica and effect
of different chemicals on growth of mangrove species
under salt induced oxidative stress which would enable
us to understand their response and subsequently lead
to rehabilitation of the degraded ecosystems. |
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| 7)
Proteomic studies in Mangrove under salinity stress
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Mangroves are ecologically important coastal
wetland forests which are significant as source of fodder,
fuel wood and as breeding ground for fish and many reef organisms.
Present at the junction of fresh and sea-water, the complex
communities require constant inflow of fresh water for the
sustenance of the component fauna and flora. The decrease
in discharge of Indus over the years has impacted this ecological
system badly which is already threatened by heavy grazing
and rampant illegal logging. In order to check further degradation,
it is necessary to make effort to rehabilitate the ecosystem
and this necessitates that the processes involved in growth
of the plants be investigated in detail. There is a need to
understand the salt stress tolerance in these plants to exploit
the available niches and unpredictable salinity conditions
prevailing during the growth period. A focus on biochemical
and molecular aspects pertaining to the synthesis and accumulation
of different stress proteins in plants growing under salinity
and monitoring the role of different osmotica involved in
metabolism of these proteins should provide some clue to proceed
in the right direction to achieve the objective.
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| 8)
Anti-nutritive factors in halophytic grasses having potential
as animal fodder |
Pakistan,
a predominantly agricultural country has serious soil salinity
problem and growing halophytic forages/fodder offers the opportunity
to reduce substantially the national deficit in live stock.
Examples of use of halophytes as forage are found in many countries
e.g. Haloxylon sp. in Iran, Atriplex sp. in Argentina and Australia,
Spartina on the east coast of USA and planting of halophyte
is now a widely accepted option in low rainfall saline regions
of Australia and many countries of north Africa to provide valuable
fodder reserves when other supplies are exhausted.
Quality and palatability are important attributes of animal
fodder. Halophytes are known to be rich in carbohydrates, oil
and proteins which may be beneficial for animal health but they
may also contain harmful organic compounds and the "accumulators"
have undesirably high salt in the foliage. These "anti-nutrient"
factors may be hazardous for animal health and identification
of halophytes containing low salts and minimum of these anti-nutrients
will help in direct feeding as a replacement of traditional
green fodder. The present projects aims at surveying the halophytic
grasses of our coastal region for assessing their constituents
which may limit their use as fodder/forage.
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