Abiotic Stres Effect on Plant by Environment

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PLANT BIOLOGY WITH RESPECT TO ABIOTIC STRESSES TO ENVIRONMENT

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Plant biology with respect to Abiotic stresses to environment

Biology assignment:-
Given by MAM MARYIM
To
Group # 4

Group members:-
UMMA-E-FARWA (34)

ADEEB DANISH (20)

MUHAMAD SHEHZAD (33)

Content
• Abiotic stress
• Abiotic stress conditions
• Drought
• Salinity
• High temperature
• Chilling
• Flooding
• Troposphere ozone
• Oxidative damage
• Defense mechanism

Plant biology with respect to Abiotic stresses to environment

ABIOTIC STRESS:-

Abiotic stress is defines as the negative impact of non-living factors on the living organisms in a specific environment Plants being sessile organisms are exposed to external factors that can be stressful in such a way that development, growth and reproduction or the yield of crops becomes compromised. Expanding extensive physiological studies, the last decades has seen a focus on genes and biochemical pathway that determine whether plants are sensitive or tolerant to the many different stress factors: heat, cold & freezing, drought salinity, flooding or oxidizing agents.

Abiotic stress conditions

The most commonly encountered stress factor are drought flooding or submergence, temperature extremes such as heat stress, cold spells and freezing and soil ion content. With the latter typically in the form of increased salinity. Stress may also occur in the form of natural or man-made excess of heavy metal ion content. In addition, defrost of inorganic and nitrogen, to name only the ions important for plant growth, may restrict plant development. Furthermore, residual of chemicals used in normal crops may generate stress; because such compounds may reach the underlying aquifer or persist in the soil finally the continued modification of the atmosphere by human activities is of some concern. One example in this respect is the acidification of soils and waterways based on acid rain. Also an increase in the concentration of ozone in the ground, deserves attention, because ozone that is generated from nitric oxides by ultraviolet (UV) light can generate oxidative stress conditions, which leads to the destruction of portions & cells, premature aging and ultimately to deteriorating ecosystems & reduced yield in crops.

A final paint to make is the consideration of compound damaging effect by multiple stress factors that act simultaneously. The lack of water in soil with naturally high ion content exemplifies a stress, which is both osmotic &ionic, but other conditions are more sublet. One example may suffice. High light whit low temperature, conditions that may coincide during early spring at high latitudes; constitute a composite stress because the energy captured by photosynthesis, a physical process, can not be converted into carbon biosynthesis, a biochemical process, which is slower at low temperature. Low temperature restricts biochemical reactions that accomplish biosynthesis and reduce the transport that accomplish biosynthesis and reduce the transport of nutrients and water form the soil to the photosymtheticaly active tissue

Abiotic external the factors are exacerbated by biotic interactions exerted by viral, bacterial or fungal pathogens or for example insect predation. Once plants have been weakened by Abiotic challenges typically increase and tend to reduce growth and reproductive success even further. The overlap of Abiotic and biotic stress conditions can be seen in typically increase and tend to reduce plant stress responses: many genes & proteins, whose actions protect plants, are induced in the following will be on this Abiotic on these Abiotic stresses that relate to temperature extremes & the availability of water.

Plant life depends on sufficient water supply for at least part of the life cycle. Water is FIRST essential as a transport medium for inorganic nutrients from the soil into aerial parts of plants....
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