Microsoft Word - 6 Bangladesh Agron. J. 2017, 20 (2): 53-66 SEEDLINGSEEDLINGSEEDLINGSEEDLING GROWTH OF WHEATGROWTH OF WHEATGROWTH OF WHEATGROWTH OF WHEAT AS AFFECTED BY SOIL SALINITYAS AFFECTED BY SOIL SALINITYAS AFFECTED BY SOIL SALINITYAS AFFECTED BY SOIL SALINITY E. SultanaE. SultanaE. SultanaE. Sultana1111, M. A. Hasan, M. A. Hasan, M. A. Hasan, M. A. Hasan2222,,,, S. SikderS. SikderS. SikderS. Sikder2222,,,, M. S. RanaM. S. RanaM. S. RanaM. S. Rana2222**** and F. Alamand F. Alamand F. Alamand F. Alam3333 1Chandgong Degree College, Dinajpur 2Department of Crop Physiology and Ecology, Hajee Mohammad Danesh Sci. and Tech. University, Dinajpur 3Office of the Registrar, Hajee Mohammad Danesh Science and Technology University, Dinajpur *Corresponding author, E-mail: sohel0901084@gmail.com (Received:Received:Received:Received: 29 May 2017, Accepted:Accepted:Accepted:Accepted: 23 August 2017) Keywords:Keywords:Keywords:Keywords: Wheat genotypes, artificially developed soil salinity and seedling growth AbstractAbstractAbstractAbstract An experiment was conducted to evaluate seedling growth of wheat under saline condition. Thirty wheat genotypes were grown in trays containing different levels of salinity (Control, 6 and 12 dSm-1) during October to December, 2013. Seedling emergence index, shoot and root length, shoot and root dry weight were found to be reduced with the increases of soil salinity level but the degree of reduction were not similar for all wheat genotypes. Salt tolerance index (STI) also indicated a wide difference in salt tolerance among the wheat genotypes. Sourav, Gourav, Shatabdi, BAW 1185, BAW 1186, BAW 1187, BAW 1189 and BAW 1193 were more salt tolerance while BAW 1177, BAW 1190 and BAW 1198 showed greater salt sensitivity than the other wheat genotypes at 6 dS m-1. However, at 12 dS m-1, Sourav, Gourav, Shatabdi, Sufi and BAW 1184 showed more salt tolerance and BAW 1183, BAW 1190, BAW 1192, BAW 1194 and BAW 97 provided greater stress sensitivity among the testing wheat genotypes. Considering both saline stress Sourav, Gourav and Shatabdi were found to be salt tolerant and BAW 1190 was saline sensitive wheat genotypes. IntroductionIntroductionIntroductionIntroduction Salt stress affects seedling growth in different ways depending on plant species (Gul and Weber 1999). Salinity affects the seedling growth of plants (Tezara et al., 2003, Rahman and Kayani, 1988) by slow or less mobilization of reserve foods (Kayani et al., 1990) suspending the cell division, enlargement (Meiri and Poljakoff – Mayber, 1970) and injuring hypocotyls (Assadian and Miyamoto, 1987). Generally, Salinity can inhibit plant growth by three major ways (Greenway and Munns, 1980): a) Water deficit arising from the more negative water potential (elevated osmotic pressure) of the soil solution; b) Specific ion toxicity usually associated with either excessive chloride or sodium uptake; and c) Nutrient ion imbalance when the excess of Na+ or Cl- leads to a diminished uptake of K+, Ca2+, NO3 - or P, or to impaired internal distribution of one or another of these ions. Therefore, Boubaker (1996) showed that seedling characteristics are also viable criteria for selecting salt tolerance in wheat in a screening experiment of wheat cultivars. The relation of various seedling growth parameters to seed yield and yield component under saline conditions are important for the development of salt tolerant cultivar. The screening of salt tolerant lines/cultivars has been attempted by many researchers on various species at seedling growth stage (Ashraf, 1999). Therefore, the present study was conducted to evaluate the response of wheat genotypes to artificially developed saline soil at seedling stage. 54 Sultana et al. Materials Materials Materials Materials The experiment was conducted on tr Physiology and Ecology, Hajee Mohammad Danesh Science and Technology University (HSTU), Dinajpur during October 2013 to December 2013. collected from research field of HSTU Exchange Capacity (CEC) and pH value of the soil were 5.60 meq/100g and 5.45 respectively. The soil contained 1.19 % organic matter, 0.69 % organic carbon, 0.07 % total Nitrogen, 16.75 ppm available Phosphorou soil was analysed at SRDI, Dinajpur). Each of 21 plastic bowl (diameter 18 cm) was filled with 10 kg of air dried soil. Different amount (0, 0.2, 0.4, 0.6, 0.8, 1.0, and 1.2 % W/W) of NaCl and Na2SO4 in a ratio of 1:1 was added in different plastic bowl thrice. Before adding, the calculated amount of salt was dissolved in 1 litre plastic bowl were then kept under shade for air drying and pulverized every day. After complete air drying the soil in each bowl was mixed properly. The soil samples were collected from each plastic bowl for determining the soil salinity was plotted against the salt concentration and a standard curve was prepared which is shown in Fig.1. Artificial saline soil of different dSm calculated amount of NaCl and Na2SO Fig.1. Relationship between soil salinity and salt concentration added in the soil. Materials Materials Materials Materials aaaand Methodsnd Methodsnd Methodsnd Methods The experiment was conducted on tray at the research field of the department of Crop Physiology and Ecology, Hajee Mohammad Danesh Science and Technology University (HSTU), Dinajpur during October 2013 to December 2013. The top soil (0-15 cm depth) was collected from research field of HSTU, Dinajpur. The soil was sandy loam and Cation Exchange Capacity (CEC) and pH value of the soil were 5.60 meq/100g and 5.45 respectively. The soil contained 1.19 % organic matter, 0.69 % organic carbon, 0.07 % total Nitrogen, 16.75 ppm available Phosphorous and 0.17 me/100g exchangeable Potassium (The soil was analysed at SRDI, Dinajpur). Each of 21 plastic bowl (diameter 18 cm) was filled with 10 kg of air dried soil. Different amount (0, 0.2, 0.4, 0.6, 0.8, 1.0, and 1.2 % W/W) of NaCl o of 1:1 was added in different plastic bowl. Each treatment was replicated thrice. Before adding, the calculated amount of salt was dissolved in 1 litre of tap water. The plastic bowl were then kept under shade for air drying and pulverized every day. After complete air drying the soil in each bowl was mixed properly. The soil samples were collected from each plastic bowl for determining the soil salinity level (Rhoades et al., 1999). The soil salinity level was plotted against the salt concentration and a standard curve was prepared which is shown in Artificial saline soil of different dSm -1 (0, 6 and 12 dS m -1) was developed by adding SO4 in a ratio of 1:1 with the help of standard curve (Fig.1). 1. Relationship between soil salinity and salt concentration added in the soil. ay at the research field of the department of Crop Physiology and Ecology, Hajee Mohammad Danesh Science and Technology University 15 cm depth) was , Dinajpur. The soil was sandy loam and Cation Exchange Capacity (CEC) and pH value of the soil were 5.60 meq/100g and 5.45 respectively. The soil contained 1.19 % organic matter, 0.69 % organic carbon, 0.07 % total s and 0.17 me/100g exchangeable Potassium (The soil was analysed at SRDI, Dinajpur). Each of 21 plastic bowl (diameter 18 cm) was filled with 10 kg of air dried soil. Different amount (0, 0.2, 0.4, 0.6, 0.8, 1.0, and 1.2 % W/W) of NaCl Each treatment was replicated of tap water. The plastic bowl were then kept under shade for air drying and pulverized every day. After complete air drying the soil in each bowl was mixed properly. The soil samples were collected from each 1999). The soil salinity level was plotted against the salt concentration and a standard curve was prepared which is shown in ) was developed by adding in a ratio of 1:1 with the help of standard curve (Fig.1). 55 Influence of Soil Salinity on Seedling Growth of Wheat Eighteen try of 1.5m x 0.6m size was filled with artificially developed saline soil of different dS m -1 (0, 6 and 12 dS m -1). For the placement of seeds of thirty wheat genotypes in different artificially developed (0, 6 and 12 dS m -1) saline soil seeds were sown in the respective saline soil containing trays at the depth of 3cm. Fifty seeds were sown in each line and there were 15 lines in each tray and every line contained single genotype. For thirty wheat genotypes two trays were required to complete a single treatment the experiment was replicated thrice having eighteen trays. Growing of seedlings were allowed up to 30 days under an artificial shade or net house. Intercultural operation like weeding was done to maintain normal growth of the crop. Normal irrigation was given in each tray in every alternate day until harvesting. At 30 days after sowing, five seedlings from each treatment combinations were sampled. Shoot and root length of individual seedling were recorded manually with scale. Then the seedlings were dried separately at 70° C for 72 h in an electric oven (Model- 03-54639, Binder, Germany) and weight were recorded with an electrical balance (Model- AND EK-300 i). Salt Tolerance Index was calculated using following formula as Goudarzi and Pakniyat (2008) Performance under salt stress condition STI = ---------------------------------------------------------------- Performance under normal stress condition The data were analyzed by partitioning the total variance with the help of computer using MSTATC program. The treatment means were compared using Tukey’s Test. Results and DiscussionResults and DiscussionResults and DiscussionResults and Discussion Emergence indexEmergence indexEmergence indexEmergence index Emergence index which indicates the speed of emergence was significantly influenced by interaction effect of salinity levels and wheat genotypes (Table 1). Emergence index was higher at control (with a range from 54.61 in Gourav to 71.44 in BAW-1182 and a mean of 63.70) moderate at moderate stress (with a range from 40.78 in BAW 1199 to 62.11 in BAW 1182 and a mean of 49.43) and lower at higher saline stress (with a range from 4.46 in BAW 1199 to 29.16 in BARI Gom 25 and a mean of 19.03). The results showed that the speed of emergence was reduced with the increment of soil salinity stress but the degree of reduction in emergence index was not similar for all wheat genotypes at moderate and higher salinity stress compared to control. At moderate soil salinity stress, wheat genotypes- Sourav,Sufi, Bijoy, Prodip, BARI Gom 25, BARI Gom 26, BARI Gom 27, BARI Gom 28, BAW 1184, BAW 1185, BAW 1187, BAW 1189, BAW 1190, BAW 1191, BAW 1192, BAW 1194, BAW 1196, BAW 1197, BAW 1198, BAW 1199, BAW 1200 and BAW 1201 showed more than 20% reduction and wheat genotypes- Gourov, BAW 1177, BAW 1182, BAW 1183, BAW 1186, BAW 1193 and BAW 1195 showed less than 20% reduction in emergence index compared to control except in Shatabdi in which emergence index was even increased. At higher soil salinity stress, only wheat genotypes Shatabdi showed less than 50% reduction and all others genotypes showed more than 50% reduction in emergence index compared to control. 56 Sultana et al. Table 1. Emergence index of different wheat genotypes as influenced by salinity levels Wheat genotypes Emergence index % change over control at 6 dS m-1 % change over control at 12 dS m-1 Control Saline (6 dS m-1) Saline (12 dS m-1) Sourav 63.87 50.79 10.75 -20.47 -83.17 Gourav 54.61 50.79 18.50 -6.99 -66.12 Shatabdi 56.65 59.58 28.84 +5.17 -49.09 Sufi 66.60 49.69 28.91 -25.39 -56.59 Bijoy 67.63 46.54 22.19 -31.18 -67.19 Prodip 64.43 48.81 14.03 -24.24 -78.22 BARI Gom-25 66.43 51.23 29.16 -22.88 -56.10 BARI Gom-26 65.22 46.70 27.90 -28.39 -57.22 BARI Gom-27 63.87 50.41 23.14 -21.07 -63.77 BARI Gom-28 69.11 53.77 16.34 -22.19 -76.36 BAW 1177 65.79 53.71 22.09 -18.36 -66.42 BAW 1182 71.44 62.11 27.82 -13.05 -61.06 BAW 1183 66.12 58.19 29.56 -11.99 -55.29 BAW 1184 69.11 51.61 24.08 -25.32 -65.16 BAW 1185 64.79 45.27 6.38 -30.12 -90.15 BAW 1186 61.21 58.77 28.80 -3.98 -52.95 BAW 1187 60.37 45.63 15.90 -24.41 -73.66 BAW 1189 60.55 42.28 9.20 -30.17 -84.81 BAW 1190 63.64 42.48 10.71 -33.25 -83.17 BAW 1191 66.34 46.94 28.47 -29.24 -57.08 BAW 1192 62.06 46.91 6.89 -24.41 -88.90 BAW 1193 58.11 50.81 24.55 -12.56 -57.75 BAW 1194 60.38 46.68 11.05 -22.69 -81.69 BAW 1195 64.06 51.87 14.11 -19.03 -77.97 BAW 1196 66.77 50.51 16.61 -24.35 -75.12 BAW 1197 67.24 46.59 17.29 -30.71 -74.29 BAW 1198 59.34 45.56 6.26 -23.22 -89.45 BAW 1199 56.16 40.78 4.46 -27.39 -92.06 BAW 1200 62.24 46.98 28.94 -24.52 -53.50 BAW 1201 66.94 36.90 18.23 -44.88 -72.77 Range 54.61-71.44 40.78-62.11 4.46-29.16 Mean 63.70 49.43 19.03 LSD (0.01) 6.25 CV (%) 8.81 Shoot lengthShoot lengthShoot lengthShoot length Shoot length of 30 days old seedling was significantly influenced by influenced by the interaction effect of soil salinity levels and wheat genotypes (Table 2). The shoot length was found to be higher at control (with a range from 33.30 cm in BAW 1193 to 53.00 cm in BAW 1182 and a mean of 41.54 cm), moderate at moderate stress (ranging from 24.20 cm in BARI Gom 25 to 38.97 cm Sourav with a mean of 29.92 cm) and lower at higher soil salinity stress (with a range from 17.50 cm in BAW 1197 to 38.90 cm in Sourav and a mean of 23.63 cm). The shoot length was found to be reduced with the increment of soil salinity stress but the degree of reduction was not similar for all wheat genotypes. 57 Influence of Soil Salinity on Seedling Growth of Wheat Table 2. Shoot length of different wheat genotypes as influenced by salinity levels Wheat genotypes Shoot length (cm) % change over control at 6 dS m-1 % change over control at 12 dS m-1 Control Saline (6 dS m-1) Saline (12 dS m-1) Sourav 40.50 38.97 38.90 -3.77 -3.95 Gourav 38.00 34.03 30.80 -10.44 -18.94 Shatabdi 35.40 32.13 26.80 -9.24 -24.29 Sufi 36.60 28.70 24.50 -21.58 -33.06 Bijoy 36.60 25.40 22.00 -30.60 -39.89 Prodip 36.80 24.60 21.00 -33.15 -42.93 BARI Gom-25 40.17 24.20 21.90 -39.75 -45.48 BARI Gom-26 39.07 26.20 21.70 -32.94 -44.45 BARI Gom-27 40.50 27.40 22.10 -32.34 -45.43 BARI Gom-28 45.50 29.00 22.20 -36.26 -51.20 BAW 1177 44.50 31.40 27.40 -29.43 -38.42 BAW 1182 53.00 35.40 24.60 -33.20 -53.58 BAW 1183 42.90 34.20 22.90 -20.27 -46.62 BAW 1184 41.80 30.30 28.10 -27.51 -32.77 BAW 1185 43.20 36.60 28.20 -15.27 -34.72 BAW 1186 47.37 38.30 27.80 -19.14 -41.31 BAW 1187 39.40 31.67 23.00 -19.61 -41.62 BAW 1189 44.30 32.90 20.50 -25.73 -53.72 BAW 1190 43.50 29.50 24.60 -32.18 -43.44 BAW 1191 40.50 26.80 19.60 -33.82 -51.60 BAW 1192 41.67 27.20 19.50 -34.72 -53.20 BAW 1193 33.30 26.13 18.80 -21.53 -43.54 BAW 1194 37.70 28.00 18.70 -25.72 -50.39 BAW 1195 40.50 30.10 21.10 -25.67 -47.90 BAW 1196 50.57 29.10 24.77 -42.45 -51.01 BAW 1197 42.60 28.80 17.50 -32.39 -58.92 BAW 1198 42.00 25.50 23.90 -39.28 -43.09 BAW 1199 42.10 27.63 17.70 -34.37 -57.95 BAW 1200 42.70 29.50 23.30 -30.91 -45.43 BAW 1201 43.70 28.10 25.10 -35.70 -42.56 Range 33.30- 53.00 24.60- 38.97 17.50- 38.90 Mean 41.54 29.92 23.63 LSD (0.01) 1.52 CV (%) 8.35 At moderate soil salinity stress, wheat genotypes-Sufi, Bijoy, Prodip, BARI Gom 25, BARI Gom 26, BARI Gom 27, BARI Gom 28, BAW 1177, BAW 1182, BAW 1183, BAW 1184, BAW 1189, BAW 1190, BAW 1191, BAW 1192, BAW 1194, BAW 1195, BAW 1196, BAW1197, BAW 1198, BAW1199, BAW 1200 and BAW1201 showed more than 20% reduction and wheat genotypes- Sourav, Gourav, Shatabdi, BAW 1185, BAW 1186 and BAW 1187 showed less than 20% reduction in shoot length compared to control. At higher soil salinity stress, wheat genotypes- BARI Gom 28, BAW 1182, BAW 1189, BAW 1191, BAW 1192, BAW 1194, BAW 1196, BAW 1197 and BAW 1199 showed more than 50% reduction and others wheat genotypes showed less than 50% reduction in shoot length compared to control. 58 Sultana et al. Root lengthRoot lengthRoot lengthRoot length Root length of 30 days old seedling was significantly influenced by the interaction effect of soil salinity levels and wheat genotypes (Table 3). The root length was found to be higher at control (with a range from 12.57 cm in Sufi to 23.20 cm in BAW 1185 and a mean of 17.03 cm), moderate at moderate stress (ranging from 8.03 cm in BAW 1194 to 16.23 cm in Gourov with a mean of 12.99 cm) and lower at higher soil salinity stress (with a range from 6.33 cm in BAW 1200 to 13.70 cm in Shatabdi and a mean of 9.44 cm). Table 3. Root length of different wheat genotypes as influenced by salinity levels Wheat genotypes Root length (cm) % change over control at 6 dS m-1 % change over control at 12 dS m-1 Control Saline (6 dS m-1) Saline (12 dS m-1) Sourav 14.13 13.70 11.50 -3.04 -18.61 Gourav 14.00 16.23 11.20 +15.93 -20.00 Shatabdi 12.84 13.20 13.70 +2.80 +6.70 Sufi 12.57 12.70 8.33 +1.03 -33.73 Bijoy 18.00 14.60 8.43 -18.89 -53.17 Prodip 18.00 14.50 12.20 -19.44 -32.22 BARI Gom-25 17.80 12.60 11.28 -29.21 -36.62 BARI Gom-26 16.10 13.00 11.60 -19.25 -27.95 BARI Gom-27 17.30 13.80 9.60 -20.23 -44.51 BARI Gom-28 16.30 12.70 11.50 -22.09 -29.45 BAW 1177 19.00 14.00 12.00 -26.32 -36.84 BAW 1182 14.80 12.80 9.70 -13.51 -34.46 BAW 1183 19.60 14.50 11.10 -26.02 -43.37 BAW 1184 18.00 10.40 11.70 -42.22 -35.00 BAW 1185 23.20 16.10 12.00 -30.60 -48.28 BAW 1186 18.50 8.30 6.73 -55.14 -63.62 BAW 1187 21.30 11.40 7.83 -46.48 -63.24 BAW 1189 16.00 8.13 7.20 -49.19 -55.00 BAW 1190 18.60 9.83 8.50 -47.15 -54.30 BAW 1191 17.30 13.10 6.90 -24.27 -60.12 BAW 1192 18.03 13.30 6.53 -26.23 -63.78 BAW 1193 16.40 14.40 7.60 -12.19 -53.66 BAW 1194 16.30 8.03 7.30 -50.74 -55.21 BAW 1195 16.30 14.30 8.00 -12.27 -50.92 BAW 1196 17.30 11.40 10.20 -34.10 -41.04 BAW 1197 14.90 15.00 8.80 +0.67 -40.94 BAW 1198 17.20 11.50 9.53 -33.14 -44.59 BAW 1199 18.00 15.60 7.70 -13.33 -57.22 BAW 1200 16.00 14.50 6.33 -9.38 -60.44 BAW 1201 17.40 16.10 8.30 -7.47 -52.30 Range 12.57- 23.20 8.03-16.23 6.33-13.70 Mean 17.03 12.99 9.44 LSD (0.01) 2.68 CV (%) 12.71 59 Influence of Soil Salinity on Seedling Growth of Wheat The root length was found to be reduced with the increment of soil salinity stress but the degree of reduction was not similar for all wheat genotypes. At moderate soil salinity stress, wheat genotypes- BARI Gom 25, BARI Gom 27, BARI Gom 28, BAW 1177, BAW 1183, BAW 1184, BAW 1185, BAW 1186, BAW 1187, BAW 1189, BAW 1190, BAW 1191, BAW 1192, BAW 1194, BAW 1196 and BAW 1198 showed more than 20% reduction and wheat genotypes- Sourav, Bijoy, Prodip, BARI Gom 26, BAW 1182, BAW 1193, BAW 1195, BAW 1199, BAW 1200 and BAW 12001 showed less than 20% reduction in germination index compared to control except Gourov, Sufi and BAW 1197 in which root length was even increased. At higher soil salinity stress, wheat genotypes- Bijoy, BAW 1186, BAW 1187, BAW 1189, BAW 1190, BAW 1191, BAW 1192, BAW 1193, BAW 1194, BAW 1195, BAW 1199, BAW 1200 and BAW 1201 showed more than 50% reduction and others wheat genotypes showed less than 50% reduction in root length compared to control. Shoot dry weightShoot dry weightShoot dry weightShoot dry weight Shoot dry weight of 30 days old seedling was significantly influenced by influenced by the interaction effect of soil salinity levels and wheat genotypes (Table 4). The shoot dry weight was found to be higher at control (with a range from 2.34 mg in Sufi to 5.01 mg in BAW 1200 and a mean of 3.33 mg), moderate at moderate stress (ranging from 0.64 mg in BARI Gom 26 to 3.18 mg in Sourav with a mean of 1.40 mg) and lower at higher soil salinity stress (with a range from 0.32 mg in BAW 1197 to 1.31 mg in BAW 1201 and a mean of 0.67 mg). Shoot dry weight was found to be reduced with the increment of soil salinity stress but the degree of reduction was not similar for all wheat genotypes. Table 4. Shoot dry weight of different wheat genotypes as influenced by salinity levels Wheat genotypes Shoot dry weight (mg) % change over control at 6 dSm-1 % change over control at 12 dSm-1 Control Saline (6 dSm-1) Saline (12 dSm-1) Sourav 2.73 3.18 1.27 +16.48 -53.47 Gourav 2.70 1.41 0.93 -47.77 -65.55 Shatabdi 2.62 1.45 1.03 -44.65 -60.68 Sufi 2.34 1.13 0.70 -51.70 -70.08 Bijoy 3.29 1.30 0.63 -60.48 -80.85 Prodip 3.17 0.88 0.60 -72.24 -81.07 BARI Gom-25 3.23 0.82 0.48 -74.61 -85.13 BARI Gom-26 2.68 0.64 0.45 -76.11 -83.21 BARI Gom-27 2.73 0.78 0.38 -71.42 -86.08 BARI Gom-28 2.72 1.01 0.32 -62.86 -88.23 BAW 1177 3.44 1.46 0.65 -57.55 -81.10 BAW 1182 3.73 1.29 0.58 -65.42 -84.45 BAW 1183 4.46 1.45 0.49 -67.48 -89.01 BAW 1184 2.86 1.23 1.17 -56.99 -59.09 BAW 1185 2.57 1.41 1.31 -45.14 -49.02 BAW 1186 3.99 2.84 1.02 -28.82 -74.43 60 Sultana et al. Wheat genotypes Shoot dry weight (mg) % change over control at 6 dSm-1 % change over control at 12 dSm-1 Control Saline (6 dSm-1) Saline (12 dSm-1) BAW 1187 2.86 1.74 0.76 -39.16 -73.42 BAW 1189 2.50 1.78 0.35 -28.80 -86.00 BAW 1190 3.79 1.03 0.44 -72.82 -88.39 BAW 1191 2.80 1.22 0.41 -56.43 -85.35 BAW 1192 3.37 1.27 0.36 -62.31 -89.31 BAW 1193 3.13 1.65 0.40 -47.28 -87.22 BAW 1194 3.98 1.36 0.36 -65.83 -90.95 BAW 1195 2.77 1.27 0.49 -54.15 -82.31 BAW 1196 3.32 1.30 0.82 -60.84 -75.30 BAW 1197 3.68 1.37 0.32 -62.77 -91.30 BAW 1198 3.88 1.40 0.75 -63.92 -80.67 BAW 1199 4.49 1.27 0.56 -71.71 -87.53 BAW 1200 5.01 1.59 0.91 -68.26 -81.83 BAW 1201 5.23 1.50 1.13 -71.32 -78.39 Range 2.34-5.01 0.64-3.18 0.32-1.13 Mean 3.33 1.40 0.67 LSD (0.01) 0.087 CV (%) 8.35 At moderate soil salinity stress, wheat genotypes-Sufi, Bijoy, Prodip, BARI Gom 25, BARI Gom 26, BARI Gom 27, BARI Gom 28, BAW 1177, BAW 1182, BAW 1183, BAW 1184, BAW 1190, BAW 1191, BAW 1192, BAW 1194, BAW 1195, BAW 1196, BAW1197, BAW 1198, BAW1199, BAW 1200 and BAW1201 showed more than 50% reduction and wheat genotypes- Gourav, Shatabdi, BAW 1185, BAW 1186, BAW 1187, BAW 1189 and BAW 1193 showed less than 50% reduction in shoot dry weight compared to control except Sourav, in which shoot dry weight was even increased.At higher soil salinity stress, wheat genotypes- Bijoy, Prodip, BARI Gom 25, BARI Gom 26, BARI Gom 27, BARI Gom 28, BAW 1177, BAW 1182, BAW 1183, BAW 1189, BAW 1190, BAW 1191, BAW 1192, BAW 1193, BAW 1194, BAW 1195, BAW 1197, BAW 1198, BAW 1199 and BAW 1200 showed more than 80% reduction and others wheat genotypes showed less than 80% reduction in shoot dry weight compared to control. Root dry weightRoot dry weightRoot dry weightRoot dry weight Root dry weight of 30 days old seedling was significantly influenced by influenced by the interaction effect of soil salinity levels and wheat genotypes (Table 5). The Root dry weight was found to be higher at control (with a range from 0.55 mg in BAW 1196 to 1.64 mg in BAW 1201 and a mean of 0.95 mg), moderate at moderate stress (ranging from 0.24 mg in BAW 1177 to 0.93 mg in BAW 1185 with a mean of 0.39 mg) and lower at higher soil salinity stress (with a range from 0.05 mg in BAW 1194 to 0.30 mg in BAW 1186 and a mean of 0.20 mg). 61 Influence of Soil Salinity on Seedling Growth of Wheat Table 5. Root dry weight of different wheat genotypes as influenced by salinity levels Wheat genotypes Root dry weight (mg) % change over control at 6 dSm-1 % change over control at 12 dSm-1 Control Saline (6 dSm-1) Saline (12 dSm-1) Sourav 0.67 0.69 0.46 +2.98 -31.34 Gourav 0.77 0.42 0.29 -45.45 -62.34 Shatabdi 0.79 0.36 0.47 -54.43 -40.51 Sufi 0.64 0.26 0.26 -59.37 -59.37 Bijoy 1.14 0.35 0.24 -69.29 -78.94 Prodip 0.88 0.26 0.23 -70.45 -73.86 BARI Gom-25 0.77 0.28 0.17 -63.63 -77.92 BARI Gom-26 0.82 0.25 0.27 -69.51 -67.07 BARI Gom-27 0.73 0.25 0.12 -65.75 -83.56 BARI Gom-28 0.75 0.26 0.15 -65.33 -80.00 BAW 1177 1.28 0.24 0.28 -81.25 -78.12 BAW 1182 1.08 0.33 0.09 -69.44 -91.66 BAW 1183 1.15 0.45 0.16 -60.87 -86.08 BAW 1184 1.27 0.40 0.32 -68.50 -74.80 BAW 1185 1.71 0.93 0.27 -45.61 -84.210 BAW 1186 1.59 0.90 0.30 -43.39 -81.13 BAW 1187 0.92 0.40 0.19 -56.52 -79.34 BAW 1189 0.71 0.52 0.09 -26.76 -87.32 BAW 1190 1.02 0.29 0.16 -71.56 -84.31 BAW 1191 0.94 0.43 0.12 -54.25 -87.23 BAW 1192 0.72 0.31 0.12 -56.94 -83.33 BAW 1193 0.81 0.47 0.09 -41.97 -88.88 BAW 1194 0.85 0.25 0.05 -70.58 -94.11 BAW 1195 0.72 0.33 0.12 -54.16 -83.33 BAW 1196 0.55 0.34 0.20 -38.18 -63.63 BAW 1197 0.86 0.33 0.09 -61.62 -89.53 BAW 1198 0.90 0.27 0.17 -70.00 -81.11 BAW 1199 1.09 0.45 0.12 -58.71 -88.99 BAW 1200 0.87 0.50 0.15 -42.52 -82.75 BAW 1201 1.64 0.45 0.18 -72.56 -89.02 Range 0.55-1.64 0.24-0.93 0.05-0.30 Mean 0.95 0.39 0.20 LSD (0.01) 0.025 CV (%) 7.76 Shoot dry weight was found to be reduced with the increment of soil salinity stress but the degree of reduction was not similar for all wheat genotypes. At moderate soil salinity stress, wheat genotypes- Shatabdi, Sufi, Bijoy, Prodip, BARI Gom 25, BARI Gom 26, BARI Gom 27, 62 Sultana et al. BARI Gom 28, BAW 1177, BAW 1182, BAW 1183, BAW 1184, BAW 1187, BAW 1190, BAW 1191, BAW 1192, BAW 1194, BAW 1195, BAW1197, BAW 1198, BAW 1199 and BAW1201 showed more than 50% reduction and wheat genotypes- Gourav, BAW 1185, BAW 1186, BAW 1187, BAW 1189, BAW 1193, BAW 1196 and BAW 1200 showed less than 50% reduction in root dry weight compared to control except Sourav, in which root dry weight was even increased. At higher soil salinity stress, wheat genotypes- BARI Gom 27, BARI Gom 28, BAW 1182, BAW 1183, BAW 1185, BAW 1186, BAW 1189, BAW 1190, BAW 1191, BAW 1192, BAW 1193, BAW 1194, BAW 1195, BAW 1197, BAW 1198, BAW 1199, BAW 1200 and BAW 1201 showed more than 80% reduction and others wheat genotypes showed less than 80% reduction in root dry weight compared to control. Seedling dry weightSeedling dry weightSeedling dry weightSeedling dry weight Seedling dry weight of 30 days old seedling was significantly influenced by influenced by the interaction effect of soil salinity levels and wheat genotypes (Table 6). The seedling dry weight was found to be higher at control (with a range from 3.00 mg in Sufi to 6.87 mg in BAW 1201 and a mean of 4.34 mg), moderate at moderate stress (ranging from 0.94 mg in BARI Gom 26 to 4.34 mg in BAW 1185 with a mean of 1.84 mg) and lower at higher soil salinity stress (with a range from 0.41 mg in BAW 1194 to 1.73 mg in Sourav and a mean of 0.89 mg). Seedling dry weight was found to be reduced with the increment of soil salinity stress but the degree of reduction was not similar for all wheat genotypes. At moderate soil salinity stress, wheat genotypes- Sufi, Bijoy, Prodip, BARI Gom 25, BARI Gom 26, BARI Gom 27, BARI Gom 28, BAW 1177, BAW 1182, BAW 1183, BAW 1184, BAW 1190, BAW 1191, BAW 1192, BAW 1194, BAW 1195, BAW 1196, BAW1197, BAW 1198, BAW 1199, BAW 1200 and BAW1201 showed more than 50% reduction and wheat genotypes- Gourav, BAW 1185, BAW 1186, BAW 1187, BAW 1189 and BAW 1193 showed less than 50% reduction in seedling dry weight compared to control except Sourav, in which seedling dry weight was even increased. At higher soil salinity stress, wheat genotypes- Prodip, Bijoy, BARI Gom 25, BARI Gom 26, BARI Gom 27, BARI Gom 28, BAW 1177, BAW 1182, BAW 1183, BAW 1189, BAW 1190, BAW 1191, BAW 1192, BAW 1193, BAW 1194, BAW 1195, BAW 1197, BAW 1198, BAW 1199, BAW 1200 and BAW 1201 showed more than 80% reduction and others wheat genotypes showed less than 80% reduction in seedling dry weight compared to control. At higher soil salinity stress Sourov, Shatabdi, Sufi, BAW1184, BAW1186, BAW1187 and BAW11896 showed comparatively lower reduction in seedling dry weight. In the present study, all parameters were affected due to salt stress. With increasing salt concentration in the environment for germination, shoot and root length and dry weight were reduced significantly. Garciarrubio et al. (2003) and Datta et al. (2009) were also found the same result. It has been reported that salinity stress significantly reduced net photosynthetic rates, increased energy losses for salt exclusion mechanism, largely decreased nutrient mobilization, suspending the cell division and enlargement and finally reduced plant growth (Meiri and Poljakoff-Mayber, 1970, Long and Baker, 1986 and Seeman and Sharkey, 1986). Salinity affects the seedling growth of plants (Tezara et al., 2003, Rahman and Kayani, 1988) by slow or less mobilization of reserve foods (Kayani et al., 1990), suspending the cell division, enlargement (Meiri and APoljakoff-Mayber, 1970) and injuring hypocotyls (Assadian and Miyamoto, 1987). 63 Influence of Soil Salinity on Seedling Growth of Wheat Table 6. Seedling dry weight of different wheat genotypes as influenced by salinity levels Wheat genotypes Seedling dry weight (mg) % change over control at 6 dSm-1 % change over control at 12 dSm-1 Control Saline (6 dSm-1) Saline (12 dSm-1) Sourav 3.40 3.87 1.73 +13.82 -49.12 Gourav 3.49 1.83 1.27 -47.56 -63.61 Shatabdi 3.42 1.87 1.50 -45.32 -56.14 Sufi 3.00 1.36 0.97 -54.66 -67.66 Bijoy 4.43 1.66 0.90 -62.52 -79.68 Prodip 4.05 1.15 0.84 -71.60 -79.25 BARI Gom-25 3.68 1.10 0.66 -70.11 -82.07 BARI Gom-26 3.50 0.94 0.72 -73.14 -79.43 BARI Gom-27 3.47 1.04 0.50 -70.03 -85.59 BARI Gom-28 3.47 1.28 0.68 -63.11 -80.40 BAW 1177 4.73 1.20 0.94 -74.63 -80.13 BAW 1182 4.83 1.63 0.68 -66.25 -85.92 BAW 1183 5.61 1.91 0.65 -65.95 -88.41 BAW 1184 4.13 1.63 1.50 -60.53 -63.68 BAW 1185 5.95 4.34 1.58 -27.06 -73.45 BAW 1186 5.50 3.75 1.32 -31.82 -76.00 BAW 1187 3.79 2.15 0.95 -43.27 -74.93 BAW 1189 3.22 2.31 0.44 -28.26 -86.33 BAW 1190 4.70 1.32 0.61 -71.91 -87.02 BAW 1191 3.83 1.65 0.54 -56.92 -85.90 BAW 1192 4.29 1.58 0.49 -63.17 -88.57 BAW 1193 3.95 2.12 0.50 -46.33 -87.34 BAW 1194 4.84 1.61 0.41 -66.74 -91.53 BAW 1195 3.50 1.60 0.62 -54.28 -82.28 BAW 1196 3.88 1.64 1.02 -57.73 -73.71 BAW 1197 4.57 1.71 0.41 -62.58 -91.03 BAW 1198 4.78 1.18 0.92 -75.31 -80.75 BAW 1199 5.53 1.73 0.68 -68.72 -87.70 BAW 1200 5.89 2.09 1.07 -64.52 -81.83 BAW 1201 6.87 1.95 1.31 -71.62 -80.93 Range 3.00-6.87 0-94-4.34 0.41-1.73 Mean 4.34 1.84 0.89 LSD (0.01) 0.025 CV (%) 2.28 The same authors found that the reduction in root and shoot deve-lopment may be due to toxic effects of the higher level of NaCl concentration as well as unbalanced nutrient uptake by the seedlings. High level of salinity may have also inhibit the root and shoot elongation due to slowing down the water uptake for overall osmotic adjustments of the plant body under high salt stress condition. Salt stress result in a considerable decrease in the fresh and dry weights of root and shoot (Chartzoulakis & Klapaki 2000, Parida and Das, 2005). But the adverse effect on seedling dry weight was different in different wheat genotypes which indicate different 64 Sultana et al. sensitivity of wheat genotypes to salt stress. Singh (2008) also found differential sensitivity of wheat genotypes based on seedling growth in their study and Karim et al (1992) suggested that seedling growth is one of the most important characters for screening salt tolerance at early stage of growth. Salt tolerance index Salt tolerance index Salt tolerance index Salt tolerance index based on sbased on sbased on sbased on seedling dry weighteedling dry weighteedling dry weighteedling dry weight Salt tolerance index (STI) of thirty wheat genotypes based on seedling dry weight (30 days old) at 6 dS m-1 artificial saline soil is presented in Fig. difference in salt tolerance among the wheat genotypes. Wheat genotypes Shatabdi, BAW 1185, BAW 1186, BAW 1187, BAW 1189 and BAW 1193 showed more than 0.5 STI and Sufi, Bijoy, Prodip, BARI Gom 25, BARI Gom 26, BARI Gom 27, BARI Gom 28, BAW 1177, BAW 1182, BAW 1183, BAW 1184, BAW 1190, BAW 1191, BAW 1192, BAW 1194, BAW 1195, BAW 1196, BAW 1197, BAW 1198, BAW 1199 and BAW 1201 provided less than 0.50 STI. Fig. 2. Salt tolerance index of different wheat genotypes based on seedling dry 6 dS m-1 artificial saline soil (Vertical bar indicates LSD Salt tolerance index based on sSalt tolerance index based on sSalt tolerance index based on sSalt tolerance index based on seedling dry weighteedling dry weighteedling dry weighteedling dry weight Salt tolerance index (STI) of thirty wheat genotypes based on seedling dry weight (30 days old) at 12 dS m-1 artificial saline soil is presented in Fig. difference in salt tolerance among the wheat genotypes. Wheat genot Shatabdi, Sufi and BAW 1184 showed more than 0.3 STI and Bijoy, Prodip, BARI Gom 25, BARI Gom 26, BARI Gom 27, BARI Gom 28, BAW 1177, BAW 1182, BAW 1183, BAW 1185, BAW 1186, BAW 1187, BAW 1189, BAW 1190, BAW 1191, BAW 1192, BAW sensitivity of wheat genotypes to salt stress. Singh et al., (2000) and Moud and Maghsoudi ferential sensitivity of wheat genotypes based on seedling growth in their (1992) suggested that seedling growth is one of the most important characters for screening salt tolerance at early stage of growth. eedling dry weighteedling dry weighteedling dry weighteedling dry weight grown at 6 dS mgrown at 6 dS mgrown at 6 dS mgrown at 6 dS m----1111 artificial saline soilartificial saline soilartificial saline soilartificial saline soil Salt tolerance index (STI) of thirty wheat genotypes based on seedling dry weight (30 days old) line soil is presented in Fig. 2. These STI values indicated a wi difference in salt tolerance among the wheat genotypes. Wheat genotypes- Sourav, Gourav, Shatabdi, BAW 1185, BAW 1186, BAW 1187, BAW 1189 and BAW 1193 showed more than 0.5 STI and Sufi, Bijoy, Prodip, BARI Gom 25, BARI Gom 26, BARI Gom 27, BARI BAW 1177, BAW 1182, BAW 1183, BAW 1184, BAW 1190, BAW 1191, BAW 1192, BAW 1194, BAW 1195, BAW 1196, BAW 1197, BAW 1198, BAW 1199 and BAW Fig. 2. Salt tolerance index of different wheat genotypes based on seedling dry weight grown at soil (Vertical bar indicates LSD value). eedling dry weighteedling dry weighteedling dry weighteedling dry weight grown at 12 dS mgrown at 12 dS mgrown at 12 dS mgrown at 12 dS m----1111 artificial saline soilartificial saline soilartificial saline soilartificial saline soil Salt tolerance index (STI) of thirty wheat genotypes based on seedling dry weight (30 days old) line soil is presented in Fig.3. These STI values indicated a wide difference in salt tolerance among the wheat genotypes. Wheat genotypes- Sourav, Gourav, Shatabdi, Sufi and BAW 1184 showed more than 0.3 STI and Bijoy, Prodip, BARI Gom 25, BARI Gom 26, BARI Gom 27, BARI Gom 28, BAW 1177, BAW 1182, BAW 1183, BAW 1185, BAW 1186, BAW 1187, BAW 1189, BAW 1190, BAW 1191, BAW 1192, BAW Moud and Maghsoudi ferential sensitivity of wheat genotypes based on seedling growth in their (1992) suggested that seedling growth is one of the most important Salt tolerance index (STI) of thirty wheat genotypes based on seedling dry weight (30 days old) 2. These STI values indicated a wide Sourav, Gourav, Shatabdi, BAW 1185, BAW 1186, BAW 1187, BAW 1189 and BAW 1193 showed more than 0.5 STI and Sufi, Bijoy, Prodip, BARI Gom 25, BARI Gom 26, BARI Gom 27, BARI BAW 1177, BAW 1182, BAW 1183, BAW 1184, BAW 1190, BAW 1191, BAW 1192, BAW 1194, BAW 1195, BAW 1196, BAW 1197, BAW 1198, BAW 1199 and BAW weight grown at Salt tolerance index (STI) of thirty wheat genotypes based on seedling dry weight (30 days old) 3. These STI values indicated a wide Sourav, Gourav, Shatabdi, Sufi and BAW 1184 showed more than 0.3 STI and Bijoy, Prodip, BARI Gom 25, BARI Gom 26, BARI Gom 27, BARI Gom 28, BAW 1177, BAW 1182, BAW 1183, BAW 1185, BAW 1186, BAW 1187, BAW 1189, BAW 1190, BAW 1191, BAW 1192, BAW Influence of Soil Salinity on Seedling Growth of Wheat 1193, BAW 1194, BAW 1195, BAW 1196, BAW 1197, BAW 1198, BAW 1199 and BAW 1201 provided less than 0.3. Fig.3. Salt tolerance index of different wheat genotypes based on seedling dry weight grown at 12 dS m-1 artificial saline soil (Vertical bar indic Salt tolerance index (STI) also indicated a wide difference in salt tolerance among the wheat genotypes. Sourav, Gourav, Shatabdi, BAW 1185, BAW 1186, BAW 1187, BAW 1189 and BAW 1193 were more salt tolerance while BAW 1177, BAW 1190 and BAW 1198 showed greater salt sensitivity than the other wheat genotypes at 6 dS m Sourav, Gourav, Shatabdi, Sufi and BAW 1 BAW 1190, BAW 1192, BAW 1194 and BAW 97 provided greater stress sensitivity among the testing wheat genotypes. Considering both saline stress Sourav, Gourav and Shatabdi were found to be salt tolerant and BAW 1190 was saline sensitive wheat genotypes. Ashraf M. 1999. Interactive effect of salt (NaCl) and Nitrogen form of growth, water relations and photosynthesis capacity of sunflower 513. Assadian N. W. and S. Miyamoto. 1987. Salt effects on alfalfa seedling emergence. Agron. J.79: 710-714. Boubaker M. 1996. Salt tolerance of durum wheat cultivars during germination and early seedling growth. Agric. Medit. 126:32-39. Influence of Soil Salinity on Seedling Growth of Wheat BAW 1194, BAW 1195, BAW 1196, BAW 1197, BAW 1198, BAW 1199 and BAW Fig.3. Salt tolerance index of different wheat genotypes based on seedling dry weight grown at soil (Vertical bar indicates LSD value). ConclusionConclusionConclusionConclusion Salt tolerance index (STI) also indicated a wide difference in salt tolerance among the wheat , BAW 1185, BAW 1186, BAW 1187, BAW 1189 and BAW 1193 were more salt tolerance while BAW 1177, BAW 1190 and BAW 1198 showed greater salt sensitivity than the other wheat genotypes at 6 dS m-1. However, at 12 dS m Sourav, Gourav, Shatabdi, Sufi and BAW 1184 showed more salt tolerance and BAW 1183, BAW 1190, BAW 1192, BAW 1194 and BAW 97 provided greater stress sensitivity among the testing wheat genotypes. Considering both saline stress Sourav, Gourav and Shatabdi were 90 was saline sensitive wheat genotypes. ReferencesReferencesReferencesReferences Ashraf M. 1999. Interactive effect of salt (NaCl) and Nitrogen form of growth, water relations and photosynthesis capacity of sunflower (Helianthus annus L.). Ann. Appl. Biol. 135: 509 W. and S. Miyamoto. 1987. Salt effects on alfalfa seedling emergence. Agron. J.79: Boubaker M. 1996. Salt tolerance of durum wheat cultivars during germination and early seedling 39. 65 BAW 1194, BAW 1195, BAW 1196, BAW 1197, BAW 1198, BAW 1199 and BAW Fig.3. Salt tolerance index of different wheat genotypes based on seedling dry weight grown at Salt tolerance index (STI) also indicated a wide difference in salt tolerance among the wheat , BAW 1185, BAW 1186, BAW 1187, BAW 1189 and BAW 1193 were more salt tolerance while BAW 1177, BAW 1190 and BAW 1198 showed . However, at 12 dS m-1, 184 showed more salt tolerance and BAW 1183, BAW 1190, BAW 1192, BAW 1194 and BAW 97 provided greater stress sensitivity among the testing wheat genotypes. Considering both saline stress Sourav, Gourav and Shatabdi were Ashraf M. 1999. Interactive effect of salt (NaCl) and Nitrogen form of growth, water relations and L.). Ann. Appl. Biol. 135: 509- W. and S. Miyamoto. 1987. Salt effects on alfalfa seedling emergence. Agron. J.79: Boubaker M. 1996. Salt tolerance of durum wheat cultivars during germination and early seedling 66 Sultana et al. Chartzoulakis K. and G. Klapaki. 2000. Response of two green house pepper hybrids to NaCl salinity during different growth stages. Sci. Hortic. 86: 247–260. Datta J. K., S. Nag, A. Banerjee. and N. K. Mondal. 2009. Impact of salt stress on five varieties of Wheat (Triticum aestivum L.) cultivars under laboratory condition. J. Appl. Sci. Environ. 13(3): 93 – 97. Garciarrubio A., J. P. Leg Aria and A. A. Covarrubias. 2003. Abscisic acid inhibits germination of mature Arabidopsis seeds by limiting the availability of energy and nutrients. Planta 2:182- 187. Goudarzi, M. and H. Pakniyat. 2008. Evaluation of wheat cultivars under salinity stress based on some agronomic and physiological traits. J. Agri. Soc. Sci. 4: 81–4. Greenway H. and R. Munns. 1980. Mechanism of salt tolerance in non-halophytes. Ann. Rev. Plant Physiol. 31. 149-190. Gul B. and D. J. Weber. 1999. Effect of salinity, light, and temperature on germination in Allenrolfea occidentalis. Can. J. Bot. 77:240- 246. Karim M. A., N. Utsunomiya and S. Shigenaga. 1992. Effect of sodium chloride on germination and growth of hexaploid triticale at early seedling stage. Japan J. Crop Sci. 61 (2):279- 284. Kayani S. A., H. H. Naqvi and I. P. Ting. 1990. Salinity effects on germination and mobilization of reserves in Jojoba seed. Crop Sci. 30 (3): 704-708. Long S. P. and N. R. Baker. 1986. Saline Terrestrial Environments. In: N. R. Baker and S. P. Long (Eds). Photosynthesis in Contrasting Environments. Pp. 63-102. Elsevier, Amsterdam. Meiri, A. and A. Poljakoff-Mayber. 1970. Effect of various salinity regimes on growth, leaf expansions and transpiration rate of bean plants. Plant Soil Sci. 109: 26-34. Moud A. M. and K. Maghsoudi. 2008. Salt stress effects on respiration and growth of germinated seeds of different wheat (Triticum aestivum L.) cultivars. World J. Agril. Sci. 4(3): 351-358. Parida A. K. and A. B. Das., 2004. Salt tolerance and salinity effect on plants: a review. Ecotoxicol. and Environ. Safely. 60: 324–349. Rahman M. and S. A. Kayani. 1988. Effects of Chloride type of salinity on root growth and anatomy of Corn (Zea mays L.). Biologia. 34 (1): 123-131. Rhoades J. D., F. Chanduvi and S. Lesch. 1999. Soil salinity assessment; methods and interpretation of electrical conductivity measurements. P: 5-6. Seeman J. R. and J. D. Sharkey. 1986. Salinity and Nitrogen effects on photosynthesis, Ribulose- 1,5 bisphosphate carboxylase and metabolites pool size in Phaseolus vulgaris L. Plant Physiol. 82: 555-560. Singh A. K., V. Prakash and E. V. D. Sastry. 2000. Effect of salinity stress on seed germination and seeding growth of wheat. Agric. Sci. Digest. 20(2): 96-98. Tezara W., D. Martinez, E. Rengifo and A. Herrera. 2003. Photosynthetic response of the tropical spiny shrub Lycium nodosum (Solanaceae) to drought, soil salinity and saline spray. Annals Bot.. 92: 757-765.