## 3 Results and Discussion
### Plant Height, Number of Tillers and Chlorophyll SPAD Value  
The plant growth is affected by salinity because of a number of factors, including osmotic stress, ionic toxicity, lack of minerals, and physiological and biochemical responses ([PERSON] et al., 2006). This study reveals that at the seedling stage, there was a significant reduction in plant height, number of fillers per plant, and plant fresh and dry matter weight of three _Chloris gayana_ genotypes with the increasing salinity levels. However, high chlorophyll content (SPAD value) was detected in salt-tolerant genotypes. These higher chlorophyll values can be ascribed to an improved photosynthetic rate and higher dry matter production ([PERSON] et al., 2006; [PERSON] et al., 2006). The reduction in chlorophyll content under marginal environments has been observed in many previous studies ([PERSON] et al., 2006; [PERSON] et al., 2006; [PERSON] et al., 2006). The plant height and the total number of tillers of three _Chloris gayana_ genotypes under different soil salinity conditions is given in Table 1. A linear decrease in plant height with increasing soil salinity was observed for all genotypes. The plant height of _Chloris gayana_ genotypes ranged between 93.0-120.8 cm for control (0 dS m\({}^{-1}\)), 92.5-117.8 cm at 5 dS m\({}^{-1}\), 81.4-103.6 cm at 10 dS m\({}^{-1}\), 60.3-78.3 cm at 15 dS m\({}^{-1}\), and 52.0-69.0 at 20 dS m\({}^{-1}\). The average plant height for all _Chloris gayana_ genotypes at 0 dS m\({}^{-1}\) was 105 cm with ILRI-6633 being the highest (120.8 cm). Likewise, the average plant height for all genotypes at the highest salinity level (20 dS m\({}^{-1}\)) was 61.6 cm with ILRI-6633 taking the lead (68.9 cm). The highest decrease in plant height with an increase in salinity level from 0 to 20 dS m\({}^{-1}\) was noted in ILRI-6633 (51.8 cm) followed by ILRI-7384 (41.0 cm) and CV-massaba (37.5 cm). The number of tillers per plant is one of the most important agronomic traits because it determines the biomass yield of the forage grasses. The results indicate that higher salinity conditions significantly affect the tilter production at maturity. The average number of tillers per plant was found to be 7.2, 7.1, 6.6, 5.9, and 4.8 at 0, 5, 10, 15, and 20 dS m\({}^{-1}\), respectively (Table 1). At 0 dS m\({}^{-1}\), ILRI-7384 gave maximum number of tillers per plant (9.4) followed by CV-massaba (6.9), and ILRI-6633 (5.4). A similar pattern was observed at higher salinity conditions (20 dS m\({}^{-1}\)) where the maximum and the minimum number of tillers per plant were recorded in ILRI-7384 (5.8) and ILRI-6633 (3.1), respectively. These results coincide with the earlier findings which show that morphological and physiological traits of plants such as the plant height, number of tillers per plant, and fresh and dry biomass yields tend to decrease with the increasing levels of salinity [31; 33; 34]. Figure 3 shows the chlorophyll content (SPAD value) of three _Chloris gayana_ genotypes. The SPAD values were found to be consistent up to a salinity level of 10 dSbm\({}^{-1}\). However, a significant reduction in SPAD values at salinity levels of 15 dSbm\({}^{-1}\) and 20 dSbm\({}^{-1}\) was observed. For all salinity levels, highest SPAD values were found in ILRI-6633 followed by ILRI-7384 and CV-massaba. The highest SPAD value (63.6) was recorded in ILRI-6633 at moderate salinity level (10 dSbm\({}^{-1}\)). However, for 20 dSbm\({}^{-1}\), SPAD values decreased significantly for all three genotypes except for ILRI-6633. Similar trends of chlorophyll content reductions with the increasing salinity have also been observed for different crops [31; 34].