The Effect of Water Stress on Some Physiological Characteristics of Two Sugar Beet (Beta vulgaris L.)  Monogerm Hybrids

Entessar AL-Jbawi* (1) Fadi Abbas (2)

(1). Sugar beet Research Department,  Crops Research Administration, General Commission for Scientific Agricultural Research  (GCSAR), Damascus, Syria.
(2). Scientific Agriculture Research Center of Homs, (GCSAR). P.O.Box 626, Homs, Syria.

(*Corresponding author: Dr. Entessar Al Jbawi, E-mail: dr.entessara@gmail.com).

Received: 02/02/ 2015                                     Accepted: 17/06/ 2015

Abstract:

The experiment was carried out in the General Commission for Scientific Agricultural Research (GCSAR) at Homs Agricultural Research Center, Homs, Syria, during 2009-2010 seasons, at winter time, to study the effect of early water stress on some physiological characteristics of sugar beet. Two genotypes (Brigita and Dorotea), were subjected to water stress by withholding water for 40 days after rainfall ceased. A split plot design with three replicates was used. Results showed that, early drought stress had a significant effect on the studied parameters. Water content (WC%) and relative water content (RWC%) were decreased in all plant parts under drought condition as compared to control.  However, WC% in taproot decreased more than blades and petioles. RWC% decrement was less in mature leaves than in old and new leaves. Under drought stress, fresh and dry weight of tops and roots were decreased. Sugar beet genotypes showed the capability to regulate its osmotic potential by increasing sodium, potassium, and soluble sugars in both, tops and roots. Results also Indicated that drought stress caused an increasing value of fluorescence origin (fo), decreasing the values of fluorescence maximum (fm), and maximum yield of quantum in photo system-II, (fv/fm). The reduction in Dorotea genotype was more drastically compare to Brigita.

Key words: Water stress, Physiological characteristics, Sugar Beet.

Full paper in Arabic: تأثير الإجهاد المائي في بعض الصفات الفيزيولوجية لهجينين وحيدي الجنين من الشوندر السكري (Beta vulgaris L.)