Growth, physiological responses, and enzymatic activities in immature stages of five Hevea brasiliensis willd clones under water stress

The effects of water stress treatment through variation in the duration of stress applied (i.e 7, 14, 21, 28 days) on growth and physiological responses of immature Hevea brasiliensis clones were investigated under glasshouse condition in comparison with a unstressed. 5 clones were found to have si...

Full description

Saved in:
Bibliographic Details
Main Author: Mohd Zan, Noorliana
Format: Thesis
Language:English
Published: 2013
Subjects:
Online Access:http://psasir.upm.edu.my/id/eprint/41462/1/ITA%202013%204R.pdf
Tags: Add Tag
No Tags, Be the first to tag this record!
id my-upm-ir.41462
record_format uketd_dc
spelling my-upm-ir.414622016-01-07T04:35:50Z Growth, physiological responses, and enzymatic activities in immature stages of five Hevea brasiliensis willd clones under water stress 2013-06 Mohd Zan, Noorliana The effects of water stress treatment through variation in the duration of stress applied (i.e 7, 14, 21, 28 days) on growth and physiological responses of immature Hevea brasiliensis clones were investigated under glasshouse condition in comparison with a unstressed. 5 clones were found to have similar responses under a well-watered control condition. Water stress significantly (p≤0.05) reduces soil moisture, biomass partitioning, specific leaf area, leaf area ratio and leaf weight ratio. Similarly, gas exchange in stressed Hevea clones had a significant effect on the net photosynthesis,stomata conductance, leaf water potential and transpiration rate. In contrast, the increase of water stress duration increased the root shoot ratio (R:S) and water use efficiency (WUE). On the other hand, in terms of clones, RRIM 3001, RRIM 2002 and RRIM 929 exhibited characteristics of maintained photosynthesis, stomata conductance, leaf water potential under water deficit by maintaining high plant water status through prompt stomata regulation (high water use efficiency), as compared to RRIM 2008 and RRIM 2014 that were sensitive to water deficit. Additionally, significant linear relationship were found between leaf water potential,stomata conductance and net photosynthesis. A significant relationship on net photosynthesis and leaf water potential was also obtained. These relationships show an ability to adapt and maintain root to shoot communication under a water stress condition that support the gas exchange findings. Water stress of Hevea plants could decrease the level of chlorophyll a, chlorophyll b, total chlorophyll content and maximum quantum efficiency of photosystem II (PS II). However, in this study chlorophyll a, chlorophyll b and total chlorophyll content were not significantly affected by water stress. The decrease of maximum quantum efficiency of photosystem II was due to the impairment of net photosynthesis which limits the availability of CO2 concentration. Moreover,water stress had rapidly increased biochemical constituents, such as ascorbate peroxidase (APX), guaiacol peroxidase (GPOX) and catalase (CAT) which exhibited progressive scavenge of reactive oxygen species (ROS) formation to prevent photo oxidation or oxidative stress. On the other hand, RRIM 3001 had the ability to maintain carbon dioxide (CO2) concentration and better scavenging defense mechanism for ROS as compared to RRIM 2014 under stressed condition. Overall results revealed that RRIM 3001 clone had the most similar water stress tolerance characteristic and suggest that water stress applied to immature Hevea clones will gradually affect their growth,physiology and trigger enzymatic antioxidants to overcome formation of ROS molecules. Hevea - Physiology Hevea - Effect of stress on Hevea - Clones 2013-06 Thesis http://psasir.upm.edu.my/id/eprint/41462/ http://psasir.upm.edu.my/id/eprint/41462/1/ITA%202013%204R.pdf application/pdf en public masters Universiti Putra Malaysia Hevea - Physiology Hevea - Effect of stress on Hevea - Clones
institution Universiti Putra Malaysia
collection PSAS Institutional Repository
language English
topic Hevea - Physiology
Hevea - Effect of stress on
Hevea - Clones
spellingShingle Hevea - Physiology
Hevea - Effect of stress on
Hevea - Clones
Mohd Zan, Noorliana
Growth, physiological responses, and enzymatic activities in immature stages of five Hevea brasiliensis willd clones under water stress
description The effects of water stress treatment through variation in the duration of stress applied (i.e 7, 14, 21, 28 days) on growth and physiological responses of immature Hevea brasiliensis clones were investigated under glasshouse condition in comparison with a unstressed. 5 clones were found to have similar responses under a well-watered control condition. Water stress significantly (p≤0.05) reduces soil moisture, biomass partitioning, specific leaf area, leaf area ratio and leaf weight ratio. Similarly, gas exchange in stressed Hevea clones had a significant effect on the net photosynthesis,stomata conductance, leaf water potential and transpiration rate. In contrast, the increase of water stress duration increased the root shoot ratio (R:S) and water use efficiency (WUE). On the other hand, in terms of clones, RRIM 3001, RRIM 2002 and RRIM 929 exhibited characteristics of maintained photosynthesis, stomata conductance, leaf water potential under water deficit by maintaining high plant water status through prompt stomata regulation (high water use efficiency), as compared to RRIM 2008 and RRIM 2014 that were sensitive to water deficit. Additionally, significant linear relationship were found between leaf water potential,stomata conductance and net photosynthesis. A significant relationship on net photosynthesis and leaf water potential was also obtained. These relationships show an ability to adapt and maintain root to shoot communication under a water stress condition that support the gas exchange findings. Water stress of Hevea plants could decrease the level of chlorophyll a, chlorophyll b, total chlorophyll content and maximum quantum efficiency of photosystem II (PS II). However, in this study chlorophyll a, chlorophyll b and total chlorophyll content were not significantly affected by water stress. The decrease of maximum quantum efficiency of photosystem II was due to the impairment of net photosynthesis which limits the availability of CO2 concentration. Moreover,water stress had rapidly increased biochemical constituents, such as ascorbate peroxidase (APX), guaiacol peroxidase (GPOX) and catalase (CAT) which exhibited progressive scavenge of reactive oxygen species (ROS) formation to prevent photo oxidation or oxidative stress. On the other hand, RRIM 3001 had the ability to maintain carbon dioxide (CO2) concentration and better scavenging defense mechanism for ROS as compared to RRIM 2014 under stressed condition. Overall results revealed that RRIM 3001 clone had the most similar water stress tolerance characteristic and suggest that water stress applied to immature Hevea clones will gradually affect their growth,physiology and trigger enzymatic antioxidants to overcome formation of ROS molecules.
format Thesis
qualification_level Master's degree
author Mohd Zan, Noorliana
author_facet Mohd Zan, Noorliana
author_sort Mohd Zan, Noorliana
title Growth, physiological responses, and enzymatic activities in immature stages of five Hevea brasiliensis willd clones under water stress
title_short Growth, physiological responses, and enzymatic activities in immature stages of five Hevea brasiliensis willd clones under water stress
title_full Growth, physiological responses, and enzymatic activities in immature stages of five Hevea brasiliensis willd clones under water stress
title_fullStr Growth, physiological responses, and enzymatic activities in immature stages of five Hevea brasiliensis willd clones under water stress
title_full_unstemmed Growth, physiological responses, and enzymatic activities in immature stages of five Hevea brasiliensis willd clones under water stress
title_sort growth, physiological responses, and enzymatic activities in immature stages of five hevea brasiliensis willd clones under water stress
granting_institution Universiti Putra Malaysia
publishDate 2013
url http://psasir.upm.edu.my/id/eprint/41462/1/ITA%202013%204R.pdf
_version_ 1747811873634385920