M. Awad Hamad
Department of Crop Science, University Putra Malaysia, 43400 UPM Serdang Selangor, Malaysia
Mohd Razi Ismail
Department of Crop Science, University Putra Malaysia, 43400 UPM Serdang Selangor, Malaysia
Marziah Mahmood
Department of Crop Science, University Putra Malaysia, 43400 UPM Serdang Selangor, Malaysia
T.M.M. Mahmud
Department of Crop Science, University Putra Malaysia, 43400 UPM Serdang Selangor, Malaysia
ABSTRACT
The effect of drying soil upon spatial distribution of leaf expansion, cell wall associated peroxidase activity and xylem sap pH in currently expanding leaves of Capsicum annuum L. was investigated. Soil water deficit reduced leaf expansion dramatically compared to plants which were well watered. Assayed cell wall associated peroxidase activity and xylem sap pH of droughted plants increased in the leaves to 10 fold than those found in well-watered plants of well-watered treatment. In the leaves of droughted plants highest cell wall associated peroxidase activities were observed in the regions of the leaf where expansion was occurring most rapidly in the well-watered plants. This increase in cell wall associated peroxidase activity and its spatial variation provides preliminary evidence that cell wall associated peroxidase activity may restrict cell expansion and subsequently leaf expansion in dicotlydenous species during periods of water deficit. Sap pH increased with increasing the intensity of water deficit and the differences were statistically significant as compared to those of well watered plants. Xylem sap of droughted plants was highest and well associated with lower transpiration rate.
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How to cite this article
M. Awad Hamad, Mohd Razi Ismail, Marziah Mahmood and T.M.M. Mahmud, 2004. The Role of Cell Wall Associated Peroxidase Activity and Xylem Sap pH in Limiting Leaf Expansion and Transpiration of Pepper Capsicum annuum L. Under Water Deficit. Journal of Biological Sciences, 4: 134-141.
DOI: 10.3923/jbs.2004.134.141
URL: https://scialert.net/abstract/?doi=jbs.2004.134.141
DOI: 10.3923/jbs.2004.134.141
URL: https://scialert.net/abstract/?doi=jbs.2004.134.141
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