Acta Botanica Hungarica 43 (3–4), pp. 367–378, 2001 THE EFFECTS OF LOW TEMPERATURE ON THE GROWTH AND TOTAL PROTEIN AMOUNT OF CHICKPEA (CICER ARIETINUM) SEEDLINGS O. MUNZUROÐLU and F. ZENGIN Biyoloji Bölümü, Fen-Edebiyat Fakültesi, Fýrat Üniversitesi, Elazýð,Turkey; E-mail: omunzuroglu@firat.edu.tr (Received 30 November, 2000) In this study, shocks of cold at the levels of 5, 3 and 1 °C have been applied to the 6-days old chickpea (Cicer arietinum L.) plants. Next, having been left to grow for 72 hours under long day photoperiod circumstances at 25 °C, the length of their root and epicotyl have been measured at certain intervals. Moreover, the protein contents of the plants exposed to low temperature shocks (1 °C) have been identified in connection with their controls. According to the results obtained, the low temperature shocks have prevented the length of the roots and epicotyl to a large extent. It is observed that the lower the tempera- ture is, the more the plant’s growth is prevented. It has also been observed that the cold stress caused by the low temperature application might be reversible. The plants get rid of this stress later in low temperatures than in high ones. The low temperature application (1 °C) has also considerably reduced the total protein amount. Key words: chickpea (Cicer arietinum L.), low temperature shock (chilling effect), plant growth, protein INTRODUCTION It is accepted that water is the most limiting factor in the productivity of plants, while the most limiting factor in geographical distribution is low temperature. This limitative effect of low temperature is caused by freez- ing and chilling. Both freezing and chilling give very important damages to agricultural plants almost everywhere in the world. Plants show high differences according to their sensibilities to low temperature. Especially plants grown in tropical and subtropical regions can be hurt and also die in low temperatures up to 20 °C that is above the point of freezing of tissue (Graham and Patterson 1982). As an example, it is claimed that a 1 °C fall in the world temperature can cause a 40% de- crease in rice production and can also change the distribution of some plants (Nielsen and Orcutt 1996). The effects on plants of freezing and chill- ing are extremely different from each other. By freezing; in extracellular ar- eas, ice-crystals are formed, protoplasmic water is gone out of the cell and 0236–6495/01/$ 5.00 © 2001 Akadémiai Kiadó, Budapest