Root fresh weight
The analysis indicates that both cadmium concentration (Cd) and variety (Aydintepe and Ispir) have significant effects on root weight. The interaction between Cd concentration and variety is also significant, suggesting that the effect of Cd on root weight differs between the two varieties (Table 1).
This study demonstrates the significant impact of cadmium (Cd) on the germination and early growth stages of
Phaseolus vulgaris, with notable differences between the Aydintepe and Ispir cultivars (Fig 1). The ANOVA results revealed that both Cd concentration and variety significantly affect root weight and their interaction further emphasizes the differential responses of the two cultivars to Cd stress.
Impact of cadmium concentration
High levels of Cd (≥32 mg/L) significantly reduced root weight, particularly at 128 mg/L, which aligns with previous research indicating the detrimental effects of Cd on plant growth (
Alloway, 1995;
Dadasoglu et al., 2022). Cd toxicity is known to disrupt several physiological processes, including water uptake, enzyme activities and hormonal balance, ultimately impairing root development (
di Toppi and Gabbrielli, 1999;
Shah et al., 2001). The significant reduction in root weight at higher Cd concentrations can be attributed to Cd-induced oxidative stress, which damages cellular structures and inhibits growth
(Satarug et al., 2003; Clemens, 2006).
Varietal differences
The Ispir variety consistently showed higher root weight compared to the Aydintepe variety across all Cd concentrations, indicating a greater tolerance to Cd stress. This finding is consistent with previous studies that have reported genetic differences in the response of plant varieties to heavy metal stress
(Grant et al., 2008; Benavides et al., 2005). The superior performance of the Ispir variety may be due to inherent genetic traits that confer better mechanisms for detoxifying and sequestering Cd, thereby reducing its toxic effects (
Clemens, 2006;
Dadasoglu et al., 2022).
Interaction effects
The significant interaction between Cd concentration and variety indicates that the response of root weight to Cd stress is cultivar-specific. This suggests that breeding programs should consider the genetic background of cultivars to enhance their tolerance to heavy metals
(Grant et al., 2008). The differential response observed in this study underscores the importance of selecting and breeding cultivars that can thrive in Cd-contaminated soils, thereby ensuring sustainable agricultural practices and food security.
Implications for agriculture
The findings of this study have important implications for agriculture, particularly in regions with Cd-contaminated soils. The higher tolerance of the Ispir variety suggests that it could be a preferable choice for cultivation in such environments. Moreover, understanding the mechanisms underlying the differential responses of plant varieties to Cd stress can inform the development of more resilient crop cultivars through selective breeding and genetic engineering (
Sanita di Toppi and Gabbrielli, 1999;
Clemens, 2006).
Future research
Further research is needed to elucidate the molecular and physiological mechanisms that confer Cd tolerance in the Ispir variety. Additionally, field studies should be conducted to validate these findings under natural growing conditions. Investigating other physiological parameters and using advanced techniques such as genomic and proteomic analyses could provide deeper insights into the plant’s response to Cd stress
(Shah et al., 2001; Benavides et al., 2005).
Hypocotyl fresh weight
The analysis indicates that cadmium concentration (Cd) and variety (Aydintepe and Ispir) do not have significant main effects on plumula fresh weight at the 0.05 significance level, but they are close to being significant (Cd Concentration: p = 0.0959, Variety: p = 0.2962). The interaction between Cd concentration and variety is also not significant (p = 0.1200) (Table 1, 2, 3).
The results indicate that cadmium concentration and variety do not have a significant effect on plumula fresh weight. This finding suggests that, within the tested range of Cd concentrations, both Aydintepe and Ispir varieties exhibit similar tolerance levels in terms of plumula fresh weight. The lack of significant interaction also suggests that the two varieties do not differ in their response to varying Cd levels (
di Toppi and Gabbrielli, 1999;
Clemens, 2006) (Fig 2).
Varietal differences and tolerance
Although the main effects were not significant, the overall trend shows that the Ispir variety tends to have slightly higher plumula fresh weight compared to Aydintepe at certain Cd concentrations. This observation aligns with previous studies highlighting the potential for genetic variation in response to Cd stress
(Grant et al., 2008; Benavides et al., 2005).
Cd concentration effects
While not statistically significant, higher Cd concentrations tend to reduce plumula fresh weight. This trend is consistent with the general understanding that Cd toxicity can impair plant growth by interfering with physiological processes
(Shah et al., 2001; Satarug et al., 2003). The detrimental effects of Cd on plumula fresh weight suggest a potential risk to plant health at elevated Cd levels (
Alloway, 1995;
Dadasoglu et al., 2022).
Implications for agriculture
Given that the effects were not significant, it suggests that within the tested Cd concentration range, both varieties may be used in Cd-contaminated soils without substantial risk to plumula fresh weight. However, the general trend indicates caution should be exercised at higher Cd levels (
Clemens, 2006).
Future research
Further research should focus on a broader range of Cd concentrations and additional growth parameters to fully understand the impact of Cd on plumula fresh weight. Investigating other physiological and biochemical responses will provide a more comprehensive understanding of Cd tolerance mechanisms in these varieties (
di Toppi and Gabbrielli, 1999; Shah
et al., 2001).
Radicle length
The analysis indicates that cadmium concentration (Cd) has a significant effect on radicle length, but variety (Aydintepe and Ispir) does not have a significant effect. The interaction between Cd concentration and variety is also not significant (Table 1, 2, 3).
The results indicate that cadmium concentration significantly reduces radicle length in both Aydintepe and Ispir varieties (Fig 3). This finding is consistent with previous studies that have demonstrated the inhibitory effects of Cd on root elongation and development
(Lux et al., 2011; Gill et al., 2011). The lack of a significant main effect of variety suggests that both varieties respond similarly to Cd stress in terms of radicle length. The significant reduction in radicle length at higher Cd concentrations is consistent with findings from
Sharma et al., (2012) and
Xu et al., (2009), who reported that Cd interferes with cell division and elongation in roots.
Cd concentration effects
High levels of Cd (≥32 mg/L) significantly reduced radicle length, which aligns with research showing that Cd toxicity interferes with cell division and elongation in roots
(Sharma et al., 2012; Xu et al., 2009). The reduction in radicle length at higher Cd concentrations can be attributed to Cd-induced oxidative stress and disruption of root cell structure
(Lux et al., 2011). Cd stress is known to generate reactive oxygen species (ROS) that cause oxidative damage to cellular components, including lipids, proteins and DNA, leading to impaired root growth
(Gill et al., 2011; Sharma et al., 2012).
Varietal differences and tolerance
While the main effect of variety was not significant, the interaction effect suggests that the Aydintepe and Ispir varieties have slightly different responses to Cd stress. This finding underscores the importance of considering genetic variation when evaluating plant responses to heavy metal toxicity (Clemens, 2006;
Gill et al., 2011). Studies have shown that genetic factors can influence the uptake, translocation and sequestration of Cd within plants, affecting their overall tolerance (
Clemens, 2006;
Lux et al., 2011).
Implications for agriculture
The significant impact of Cd on radicle length highlights the potential risk of Cd contamination in agricultural soils. The general similarity in response between the two varieties suggests that both could be used in Cd-contaminated soils, but attention should be given to soil Cd levels to prevent growth inhibition
(Xu et al., 2009). Implementing phytoremediation strategies, such as using Cd-tolerant plant varieties and soil amendments, can help mitigate Cd toxicity in agricultural settings
(Gill et al., 2011).
Future research
Further research should explore the molecular and physiological mechanisms underlying the differential responses of the two varieties to Cd stress. Field studies and advanced techniques such as proteomic and transcriptomic analyses could provide deeper insights into Cd tolerance mechanisms
(Lux et al., 2011; Sharma et al., 2012). Additionally, investigating the role of antioxidants and other protective compounds in enhancing Cd tolerance may offer new strategies for developing more resilient crop varieties (
Clemens, 2006;
Xu et al., 2009).
Plumula length
The analysis indicates that cadmium concentration (Cd) does not have a significant main effect on plumula length, but variety (Aydintepe and Ispir) has a significant effect. The interaction between Cd concentration and variety is not significant (Table 1, 2, 3).
The results indicate that cadmium concentration does not significantly affect plumula length in either variety (Fig 4). This finding contrasts with previous studies that have reported Cd’s inhibitory effects on stem elongation (Lux
et al., 2011;
Gill et al., 2011). However, the significant main effect of variety suggests that the Aydintepe variety consistently exhibits longer plumula length compared to Ispir, regardless of Cd concentration. This indicates that Aydintepe may have inherent genetic advantages contributing to better growth performance (Grant
et al., 2008).
Cd concentration effects
The lack of significant effect of Cd concentration on plumula length suggests that within the tested range, Cd may not strongly inhibit stem elongation in these varieties. This could be due to various physiological adaptations that mitigate the effects of Cd on plumula growth
(Sharma et al., 2012; Xu et al., 2009). For instance, plants may employ mechanisms such as enhanced antioxidant activity to counteract Cd-induced oxidative stress, thereby protecting plumula length
(Lux et al., 2011). Germination and seedling growth in red mung beans were negatively affected under cadmium stress (
Akar and Atis, 2019).
Varietal differences and tolerance
The significant difference in plumula length between Aydintepe and Ispir varieties highlights the importance of genetic factors in determining growth performance under stress conditions. Aydintepe’s longer plumula length suggests better adaptation and potential resilience to environmental stressors, including heavy metal contamination (
Clemens, 2006;
Gill et al., 2011). This genetic advantage could be exploited in breeding programs aimed at improving crop performance in contaminated soils
(Grant et al., 2008).
Implications for agriculture
The significant varietal differences in plumula length suggest that Aydintepe may be a preferable choice for cultivation in regions with potential Cd contamination, as it exhibits superior growth characteristics. Implementing such varieties could enhance crop productivity and resilience in contaminated soils
(Sharma et al., 2012).
Future research
Further research should focus on elucidating the molecular and genetic basis for the observed varietal differences in plumula length. Advanced techniques such as genomics and transcriptomics could provide deeper insights into the mechanisms underlying differential growth responses to Cd stress
(Lux et al., 2011; Xu et al., 2009). Additionally, investigating other growth parameters and environmental stressors could offer a more comprehensive understanding of plant tolerance mechanisms
(Gill et al., 2011).
Germination percentage
The analysis indicates that cadmium concentration (Cd) has a significant effect on germination percentage, but variety (Aydintepe and Ispir) does not have a significant effect. The interaction between Cd concentration and variety is also not significant (Table 1, 2, 3).
The results indicate that cadmium concentration significantly reduces germination percentage in both Aydintepe and Ispir varieties (Fig 5). This finding is consistent with previous studies that have demonstrated the inhibitory effects of Cd on seed germination
(Das et al., 1997). The lack of a significant main effect of variety suggests that both varieties respond similarly to Cd stress in terms of germination percentage.
Cd concentration effects
High levels of Cd (≥64 mg/L) significantly reduced germination percentage, which aligns with research showing that Cd toxicity interferes with seed germination processes, such as water uptake, enzyme activation and hormonal balance
(Liu et al., 2007). The reduction in germination percentage at higher Cd concentrations can be attributed to Cd-induced oxidative stress and disruption of cellular metabolism
(Das et al., 1997). The adverse effects of cadmium on the germination characteristics of lettuce seeds were clearly observed (
Dogan, 2018). Germination and seedling growth in red mung beans were negatively affected under cadmium stress (
Akar and Atis, 2019). On the other it is reported that the germination rate of sweet sorghum seeds significantly decreased when exposed to cadmium stress (
Icin and Ertekin, 2024).
Varietal differences and tolerance
While the main effect of variety was not significant, the interaction effect was also not significant. This suggests that the Aydintepe and Ispir varieties have similar responses to Cd stress regarding germination percentage. This finding underscores the importance of considering genetic variation when evaluating plant responses to heavy metal toxicity (
Clemens, 2006).
Implications for agriculture
The significant impact of Cd on germination percentage highlights the potential risk of Cd contamination in agricultural soils. The general similarity in response between the two varieties suggests that both could be used in Cd-contaminated soils, but attention should be given to soil Cd levels to prevent germination inhibition
(Liu et al., 2007). Implementing phytoremediation strategies, such as using Cd-tolerant plant varieties and soil amendments, can help mitigate Cd toxicity in agricultural settings
(Gill et al., 2011).
Future research
Further research should explore the molecular and physiological mechanisms underlying the differential responses of the two varieties to Cd stress. Field studies and advanced techniques such as proteomic and transcriptomic analyses could provide deeper insights into Cd tolerance mechanisms
(Lux et al., 2011; Sharma et al., 2012). Additionally, investigating the role of antioxidants and other protective compounds in enhancing Cd tolerance may offer new strategies for developing more resilient crop varieties (
Clemens, 2006;
Xu et al., 2009).
