Effect of γ-Irradiation on the Growth and Yield Response of Three Varieties of Pea (Pisum spp.)

Abstract

In this study, three pea varieties (Pisum sativum), including one field pea variety ‘Dodoni’, and two varieties of garden peas ‘Early Onward’ and ‘Rondo’, were irradiated with 100 Gy gamma rays. The irradiated seeds were then cultivated in the experimental field of the Plant Breeding and Agricultural Experimentation Laboratory of the Agricultural University of Athens, in the period of 2021–2022, affording them the chance to reveal their full potential under natural environmental conditions. The M1 generation plants were compared to non-irradiated plants in terms of their agro-morphological traits. The results indicate a statistically significant difference on several traits: plant height, plant weight, dry biomass, pod length, and the number of seeds per pod. On the other hand, no significant difference was detected in: plant growth rate, the number of shoots and leaves per plant, pods and seed yield per plant, and 1000-seed weight. However, the three pea varieties did not seem to respond in the same way. The M1 generation plants of the two garden pea varieties (‘Early Onward’ and ‘Rondo’) showed a shorter plant height and pod length than their corresponding non-irradiated plants. Likewise, the number of seeds per pod for both ‘Early Onward’ and ‘Dodoni’ was lower for the mutant plants than it was for the plants used as the control. In contrast, mutant plants of the ‘Dodoni’ variety indicated a greater plant weight and dry biomass per plant compared to non-irradiated plants. Finally, the correlation found between agronomic traits was the same regardless of the treatment (control and mutant plants). The number of seeds per plant indicated a positive correlation with the pods per plant and plant weight. Similarly, the dry biomass was positively correlated with plant weight, while being negatively correlated with pod length. Thus, the results obtained in the present study clearly indicate that there were differences between seeds irradiated with gamma rays and non-irradiated seeds in terms of their overall performance and various quantitative pea traits, which should to be further investigated in M2 and the following generations. Peas have gathered a significant market interest and demand. Given their narrow genetic base, we employed gamma irradiation technology, which can be effectively integrated with omics technologies in future generations. This study underscores the necessity to explore performance characteristics and integrate them with quality traits. Our findings reveal that each generation exhibits unique attributes, and specifically, provide a valuable foundation for identifying valuable characteristics for future breeding programs.

1. Introduction

The term ‘mutation’ was introduced in 1901 by the Dutch botanist and geneticist Hugo de Vries. The term describes any change that occurs in the number or sequence of nucleotides in an organism [1]. After the first successful experiment in mutagenesis in 1927, scientists gradually discovered more interesting ways to induce mutations in plant species [2]. These methods are categorized into physical and chemical modes. Physical methods include radiation, with the main types being X-rays, alpha–beta–gamma rays, fast and thermal neutrons, and heavy ions. Similarly, chemical methods involve various mutagenic substances that can affect the genetic material without killing the organism. Examples of such substances include EMS (ethyl methane sulfonate), sodium azide, acridine orange, and others [3].

While these practices were initially met with skepticism, improving plants through mutagenesis has proven to be a highly useful, fast, and cost-effective tool for creating new allelic variations [4]. Mutagenesis has become much more accepted by the consumers/public compared to genetically modified techniques (GMOs), which still face criticism today [5]. Finding useful mutations in a large plant population can be a challenging task. With the likelihood of a mutation occurring at a specific genetic locus estimated to be 1 in 10,000 cells, studying a population of at least 1000 plants is recommended to identify a useful mutation [6]. Despite the difficulties, the technique of mutagenesis is very useful for creating exploitable variability that can be effectively incorporated into breeding programs. This variability can encompass traits that affect plant adaptability, yield, or even the quality [7]. To date, there are a plethora of varieties that have arisen through mutagenesis, with 80% of them originating from the use of physical methods (radiation). Within this percentage, 70% of the varieties were irradiated with gamma radiation [8]. A review study [9] found that, in 28 studies from 2016 to 2020 on mutagenesis, 80% used gamma radiation for their experiments and 96% had seeds as their planting materials.

Gamma radiation belongs to ionizing radiation with very short wavelengths, less than 0.01 nm, making it highly penetrating. It is readily produced and surpasses other physical mutagenic methods in its attributes [10]. It has a mutagenic effect on DNA through breaking a double strand or a single strand through introducing lesions. Furthermore, it can induce various changes in the chromosome structure, leading to different consequences for the organism [11]. According to statistics from the IAEA/FAO for the year 2018, from the 3200 varieties created that year through mutagenesis programs, 80% resulted from the use of gamma radiation [12]. In plant breeding, it has been demonstrated through numerous experiments that the intensity and duration of gamma radiation exposure play a crucial role in the functional and structural changes that occur [13]. The so-called “radiation dose” is the product of the radiation intensity and the duration of exposure to it [5]. The ideal radiation dose is defined as the one that causes mortality in 50% of the seeds [5]. For instance, the seeds of a lentil variety were irradiated with a range of acute gamma irradiation doses (0, 100, 150, 200, 250, 300, and 350 Gy) to induce unique genetic variability. The optimal dosage of gamma radiation was determined as 217.2 Gy based on the dose at which 50% growth reduction is observed [14]. For soybean mutation breeding, the optimal dose was determined to be from 263 Gy to 343 Gy when using gamma rays. This optimal dose is slightly lower than the shoulder dose (Dq) but is considered the best for breeding purposes [15]. Rana et al. (2024) [16] exposed four bread wheat varieties (HS 490, HPW 89, HPW 360, and HPW 251) to six different doses of gamma rays ranging from 175 to 300 Gy, using a Co60 (BARC in Mumbai, India). Among the tested doses, gamma ray irradiation between 250 and 300 Gy was proved to be the most effective. Radiation can be characterized as a stressor that plants need to cope with [17]. The induced mutations become more stable in the descendants of each new generation and no longer exhibit chimeric characteristics like the plants of the first generation (M1) [18]. Therefore, by selecting plants that exhibit desirable phenotypes from the M2 or M3 generations, research can be conducted at the genotypic and metabolic levels to determine the changes ultimately brought about by the process of radiation [19].

The pea plant (Pisum spp.) belongs to the legume family (Fabaceae) and is one of the economically significant legumes cultivated both for human consumption and animal feed. It serves as a good source of dietary fiber and phytic acid, contributing to organism health. Peas are increasingly popular in the food industry for their nutritional benefits and hypoallergenic properties, as they are not among the major allergens. Although cooking can increase the allergenicity of some allergens (named Pis s 1, Pis s 2, and Pis s 3), peas remain a valuable source of vegan protein and are safe for most people to consume, with only a few known allergens, thus making them ideal for vegetarian and vegan products [20]. Moreover, it is an important source of proteins, which are of high biological value and contain all essential amino acids in balance. Additionally, peas offer prebiotic carbohydrates and calcium, while also containing vitamins and trace elements, particularly iron (Fe) and zinc (Zn) [5]. Varieties of Pisum sativum var. sativum, mainly intended for human consumption, have densely arranged seeds in their pods. These seeds are consumed either as fresh green peas, canned, or preserved under refrigeration or as dried seeds. On the other hand, Pisum sativum var. arvense varieties are cultivated for animal feed, providing dried seeds as coarsely ground flour and biomass as fodder and bedding material.

A sustainable solution to the numerous issues that jeopardize the world’s food security is increased farm productivity with small ecological footprints. The agricultural production packages required to feed an ever-increasing human population, satisfy the needs of other industries for food-based substrates, and maintain an unharmed environment will consist of a diversified variety of hardy, high-yielding, and input-efficient crop types. Most staple crops’ varieties that are now on the market do not work with the envisioned highly effective yet low-input agricultural production systems. This suggests that a new crop variety portfolio will need to be developed. Despite being a nearly century-old approach, induced mutagenesis has shown to help unlock potentials in pea cultivation and benefit plant breeders. There is a clear need for new optimized pea products that are non-GMO to meet the growing demand for plant-based products. For instance, peas are a promising alternative to soy protein, as they have similar protein profiles but are non-GMO and low in allergenicity [21]. Despite the increasing interest in recent years and its economic importance, pea still has small variability range in qualitative and quantitative traits [22]. At the same time, natural mutations happen at such a low frequency that new useful traits are extremely rare to come by; as such, induced mutations could provide the desired solution in increasing the species’ genetic variability [23]. Induced mutagenesis is a tested, reliable, affordable, and safe method of plant breeding. Crop varieties developed through the use of induced mutagenesis are improving livelihoods and enhancing global food and nutritional security [24]. Positive effects on the characteristics of Pisum sativum L. have been recorded regarding plant height, leaf number, and dry biomass after exposure to 30 Gy gamma radiation [25]. Khan et al. (2018) [26] concluded that gamma radiation intensities of around 70 Gy are ideal for improving agronomic traits in pea varieties.

In this study, we evaluate the first mutant generation (M1) of three pea (Pisum spp.) varieties induced by mutagenesis with gamma radiation at a dose of 100 Gy. The focus of our comparative study lies in comparing irradiated and non-irradiated plants, emphasizing characteristics related to vegetative growth and yield. To broaden our objectives, M1 evaluation findings are included in M2 comparisons, as well as assessing the varieties for their sensitivity to radiation. Specifically, we examine two edible varieties, Pisum sativum var. sativum (Early Onward and Rondo), and one livestock-feed variety, Pisum sativum var. arvense (Dodoni). This study focuses on a fundamental description of the M1 generation plants and, even though it is the first generation, differences can already be detected; thus, these findings can be the benchmark for comparison with future breeding generations. Additionally, it could be helpful for further marker-assisted breeding programs combined with other ‘omics’ technologies for the improvement in yield parameters of pea varieties.

2. Materials and Methods

2.1. Mutagenic Treatment and Main Characters Observed

The seeds (M0) of three pea varieties (one field pea, Pisum sativum var. arvense (L.), and two garden peas, Pisum sativum var. sativum (L.)) were sent to the International Atomic Energy Agency (IAEA), Seibersdorf, Austria, and exposed to 100 Gy of gamma irradiation according to the previable tests for variety sensitivity to the mutagen. According to Pandey et al. (2022) [5], the ideal dose of gamma radiation to be used is the one that causes 50% lethality (LD50) to the seeds of the specific plant species. After the previable tests, it was found that 100 Gy radiation was the ideal dose for our experiment as it caused LD50 to the ‘Dodoni’ variety (50.19% survival rate). At the same time, non-irradiated seeds were sown as the initial control (10% from the total number of seeds of each population originating from each of the three varieties). The experimental site was at the Agricultural University of Athens (37°59′2″ N 23°42′19″ E), where the irradiated and the non-irradiated seeds were established separately in nearby fields. A randomized complete block (RCB) design with 4 replications and 3 plots in each replication was used. In total, 540 irradiated seeds were sown for each pea variety, in plots of 3.8 m × 5.8 m, within 9 rows per plot. In the same manner, 64 non-irradiated seeds were sown for each of the three varieties, in plots of 1.2 m × 6.4 m, within 3 rows per plot. The aim of this design was the observation of irradiated and non-irradiated seeds under natural environmental conditions, and thus, their overall field performance could be evaluated. According to a study on mutagenesis in rice [27], a field experiment under non-artificial conditions is essential to reveal the plant’s actual potential of abiotic tolerance.

2.2. Plant Material

Three pea varieties were used, one field variety (‘Dodoni’), and two garden pea (edible) varieties (‘Early Onward’ and ‘Rondo’). ‘Dodoni’ is a medium-to-late-maturing variety that is well-adapted to Greek environmental conditions. It is a climbing pea variety with a maximum height of 155 cm. ‘Dodoni’ has great cold tolerance (till −18 °C), and medium tolerance to drought, as well as resistance to several diseases, such as septoriasis and fusarium. The variety’s grain production is up to 420–692 kg/ha; as for the hay production, it comes up to 1235–1483 kg/ha. The weight of 1000 seeds is 90–110 g [28]. ‘Early Onward’ is an early-to-medium-maturing variety of rapid growth and good adaptation to different environments [29]. The plant height does not outgrow 70–75 cm. The produced pods are 8–11 cm of length and contain an average of 7–9 seeds. Two pods grow to each node starting from the 13th node. ‘Rondo’ is a medium-maturing variety with a good cold tolerance. It also has resistance to Ascochyta pisi. ‘Rondo’ is a productive variety that grows 70–80 cm of height. The pods length is 10–12 cm, and they contain an average of 8–9 peas.

2.3. Field Experiment Growth Conditions

The field experiment was carried out from November 2021 to June 2022. The plants were cultivated under natural environmental conditions. The field was weeded by hand and with a hoe every week. Furthermore, cultivation practices such as irrigation, manure, and insecticides were carried out whenever necessary, for example, during the flowering phase in April 2022. During the final phase of the cultivation, the plots were covered with an appropriate net so as to reduce the seeds being eaten by pigeons. Lastly, many seeds were damaged by pea weevils (Bruchus pisorum); most of them were from the control plants. Finally, harvesting was carried out by hand between 20 May and 15 June 2022. All the M1 seeds were collected separately for each plant to be used the following year for the continuation of the experiment.

2.4. Weather Conditions

The temperature, the precipitation, and the sunshine duration, during the months that our experiment took place, are indicated below (Figure 1). The meteorological data are according to the Hellenic National Meteorological Service (HNMS) for the area where the experimental site was placed.

Two noteworthy meteorological phenomena were the snowfall that happened at the end of January 2022 and the strong winds on 19 and 20 May 2022. While the snow seemed to have little effect on the plants, the wind was responsible for extensive damage. Many seeds and pods were scattered, several stems were broken, and some plants were uprooted and removed from the experimental field.

2.5. Data Collection

Observations on agro-morphological characters were made throughout the experiment: growth rate (plant height (cm) and the number of shoots and leaves per plant), plant weight (g), dry biomass per plant (g), pods and seed yield per plant, pod length (cm), number of seeds per pod, and 1000-seed weight (g). The data were recorded on randomly selected plants from each treatment. The pre-decided amount of plants was 60 control plants (20 from each variety) and 150 mutant plants (50 from each variety). Among the control plants, five plants per variety from each block were to be selected, but due to the lack of plants, the number of selected control plants was reduced to 52 (20 ‘Dodoni’, 19 ‘Early Onward’, and 13 ‘Rondo’). As for the mutant plants, 50 plants were selected from the variety ‘Dodoni’. Unfortunately, the plants of the varieties ‘Early Onward’ and ‘Rondo’, again, were not enough to select the pre-decided fifty plants from each. In this case, for both varieties, the total amount of their plants was used for the observations, with 43 plants in total (38 ‘Early Onward’ and 5 ‘Rondo’). From these 93 mutant plants, only 76 survived until the harvest (42 ‘Dodoni’, 29 ‘Early Onward’, and 5 ‘Rondo’), and so all the post-harvest data were taken from those.

2.6. Statistical Analysis

All experimental data were analyzed by a one-way analysis of variance (ANOVA) at a significance level of α = 0.05, while a Tukey’s HSD test was used for multiple comparisons. The results of the analysis are presented in Figure 2. In order to examine and reveal the relationships between post-harvest variables, a bivariate analysis was used (Figure 3). The statistical analysis was performed through the R programming language using the packages agricolae and ggplot2.

3. Results and Discussion

3.1. Agro-Morphological Traits

Agro-morphological data were collected at seven specific dates throughout the experimental period in order to determine the plants’ growth rate. The key variables recorded included the height of plants, the number of shoots, and the number of leaves (Figure 2). The varieties under investigation were ‘Dodoni’, ‘Early Onward’, and ‘Rondo’, and each variety was subjected to both mutant and control treatments.

According to the overall view, the mutant plants did not have statistically significant differences compared to the control plants as for their growth rate, plant height, and number of shoots and leaves. The only exception was the height of the varieties ‘Early Onward’ and ‘Rondo’, which showed a statistically significant reduction for the mutant plants. Noteworthy is the mean height at the last date (27 April 2022), when the control plants had mean heights of 50.68 cm and 55.38 cm for the varieties ‘Early Onward’ and ‘Rondo’, respectively, while on the same date, the mutant plants had 36.42 cm and 42.8 cm, respectively (Figure 2A). Regarding the height of the plants, the ‘Dodoni’ variety consistently demonstrated distinct height variations compared to the other varieties at all seven recorded dates. Specifically for the last date (27 April 2022), the mean height of the mutant plants for ‘Dodoni’ was 77.48 cm, and for the ‘Early Onward’ and ‘Rondo’ varieties, the mean heights of the mutant plants were 36.42 cm and 42.8 cm, respectively. The differences were statistically significant (p < 0.05). Similar trends were observed in the number of shoots and leaves. The ‘Dodoni’ variety consistently displayed a statistically significant divergence in shoot and leaf numbers compared to the other varieties across all dates. Regarding the number of leaves, it is worth noting that ‘Dodoni’ had 155.48 leaves compared to ‘Early Onward’ and ‘Rondo’, which had 37.65 and 52.6 leaves, respectively, on the last date (27 April 2022) (Figure 2C).

According to several similar studies, it has been found that high doses of gamma radiation reduce the maximum plant height. This reduction was observed in cowpea [8,30], in rice [31], and in pea varieties [32]. Similarly, there are studies that found gamma radiation’s negative effect on the number of shoots and leaves in cowpea [30] and in black gram [33], while the study of Masry et al. (2019) [34] indicated that radiation has no significant effect on the number of shouts and leaves per plant. In accordance with this latter study, the mutant plants of the ‘Dodoni’ variety in our experiment indicated no significant difference compared to the control plants as for the number of shoots and leaves per plant. In the same manner, no statistically significant difference was observed for the ‘Dodoni’ plants’ height between the control and the mutant plants. This observation, however, does not align with the results of El-Ghareeb’s experiment in 2006 [32], in which gamma radiation reduced the maximum plant height in pea varieties.

3.2. Post-Harvest Characteristics

The analysis of variance for the post-harvest variables showed that statistically significant differences between the combinations of treatments (control and mutant) and varieties (‘Dodoni’, ‘Early Onward’, and ‘Rondo’) were observed for the variables of plant weight, dry biomass, pod length, number of seeds per pod, and seed weight (Figure 3a,b,d,e,g). In contrast, no statistically significant difference was found for the variables of total number of pods and seeds per plant (Figure 3c,f). A statistically significant difference in plant weight and biomass traits was exclusively evident in the ‘Dodoni’ variety comparing the mutant to the control plants; the former had a 112.5 g mean plant weight and 78.52 g mean dry biomass, while the latter had 68.8 g and 55.82 g, respectively (Figure 3a,b). Regarding the characteristics of pod length and number of seeds per pod, the variety ‘Dodoni’, regardless of the mutation, was statistically significantly different from the varieties ‘Early Onward’ and ‘Rondo’ (Figure 3d,e). Noteworthily, the mutant plants of ‘Dodoni’ had a 3.03 cm mean pod length, with 1.97 mean number of seeds per pod; on the other hand, ‘Early Onward’ and ‘Rondo’ had 4.37 cm and 5.68 cm mean pod length and 2.32 and 4.21 mean number of seeds per pod, respectively (Figure 3d,e). It is worth noting that, as for the variable of pod length, the varieties ‘Early Onward’ and ‘Rondo’ had a statistically significant difference between the treatments. The mutant plants of both varieties had a reduced pod length compared to their respective control plants, which had a mean pod length of 6.56 cm for ‘Early Onward’ and 6.77 cm for ‘Rondo’ (Figure 3d). Similarly, for the variable of seeds per pod, there was a statistically significant difference between the mutant and the control plants of both ‘Dodoni’ and ‘Early Onward’. Fewer seeds per pod were present in the mutant plants compared to the control plants, which had a 3.86 mean number of seeds per pod for the variety ‘Dodoni’ and 4.49 for ‘Early Onward’ (Figure 3e).

The key findings of another study, aimed at testing the efficacy of gamma irradiation doses (0.8, 1.6, 2.4, and 3.6 kGy using Cobalt-60) on the growth and yield performance of edible pea (Pisum sativum L.) in a pot culture experiment, revealed that the 3.2 kGy dose significantly reduced the pod length by 17.71% but did not significantly affect the number of seeds per pod. The 1.6 kGy dose significantly reduced the number of seeds per pod by 14.21%. The 3.6 kGy dose did not significantly affect the number of pods per plant or the number of seeds per pod. Overall, higher doses of gamma irradiation, particularly 3.2 kGy, had detrimental effects on pod length, while moderate doses like 1.6 kGy reduced the number of seeds per pod but did not affect the pod length or the number of pods per plant [18]. As it is indicated by other studies, the number of pods per plant was increased by the gamma radiation treatment for pea varieties [34]. On the other hand, some plant species had a reduction in their yield, such as cowpea [30] and barley [26]. The number of seeds per pod was reduced for mutant plants of pea varieties [35,36] and cowpea [30]. In our experiment, the total yield of all three pea varieties seemed to remain unaffected by the gamma radiation treatment, which was not observed in other studies. In the case of the number of seeds per pod, our experiment confirmed the results of previous studies, as both the plants of the ‘Dodoni’ and ‘Early Onward’ varieties showed reductions in this characteristic. On the other hand, ‘Rondo’ remained unaffected by the gamma radiation treatment regarding the number of seeds per pod.

The overall conclusion from several studies is that gamma radiation can have a positive, negative, or neutral effect on plants’ agro-morphological traits depending on the radiation dose (KR) used, in correlation with the plant species that is irradiated. Different plant species have different responses to different gamma radiation doses. A study on groundnut conducted two experiments that showed the impact of varying levels of gamma radiation on the growth and yield characteristics. The first experiment, spanning radiation levels from 0 to 100 Gy, yielded no significant differences among the treatments. However, in the second experiment, spanning radiation levels from 0 to 500 Gy, significant differences were observed in the measured variables. Notable increases were exhibited in the variables of the number of pods (46%), 100-seed weight (47.7%), total yield (65.6%), root fresh weight (69.8%), and shoot fresh weight (123.3%) for the seeds exposed to 200 Gy [37].

As for the ideal dose for obtaining the field pea variety’s best agronomic traits, this was found to be 225 Gy, according to another study [5]. The same study found that the gamma radiation doses of 150 and 200 Gy yield survival rates of 89 and 71%, respectively, for edible pea varieties.

3.3. Correlation Coefficients

In Figure 4, the correlation coefficients among the post-harvest variables of the experiment are presented by treatment (control and mutant plants). The highest positive statistically significant correlation coefficients in the control plants were observed between the variables of the number of seeds and pods per plant (r = 0.95, p-value < 0.001), dry biomass and plant weight (r = 0.85, p-value < 0.001), number of seeds and plant weight (r = 0.78, p-value < 0.001), and plant weight and pods per plant (r = 0.77, p-value < 0.001). In the mutant plants, there were positive and statistically significant correlation coefficients between plant weight and pods per plant (r = 0.79, p-value < 0.001), dry biomass and plant weight (r = 0.73, p-value < 0.001), the number of seeds and pods per plant (r = 0.77, p-value < 0.001), and plant weight (r = 0.74, p-value < 0.001). Additionally, there were negative and statistically significant correlations between the variables of dry biomass and pod length (r = −0.63, p-value < 0.001) and seeds per pod (r = −0.52, p-value < 0.001). In both treatments, the number of seeds per plant was significantly positively correlated with the pods per plant and plant weight. The dry biomass was significantly positively correlated with plant weight and significantly negatively correlated with pod length. On the other hand, the variables of seeds per pod and pods per plant (r = −0.32, p-value < 0.001) and plant weight (r = −0.32, p-value < 0.001) were negatively correlated in the mutant plants; however, a weak positive correlation was found in the control plants (Figure 4).

Likewise, a study on Bambara groundnut found strong, positive, and highly significant correlations between several key traits. The total number of pods per plant had a strong, positive, and highly significant correlation with the number of seeds per plant, fresh seed weight, dry seed weight, and fresh pod weight. Yield per plant was strongly and positively correlated with the number of seeds per plant. Dry seed weight was strongly correlated with fresh seed weight and fresh pod weight. Plant height was positively correlated with the total number of pods, number of seeds per pod, fresh seed weight, dry seed weight, and fresh pod weight [38].

4. Conclusions and Future Perspectives

Almost half of the studied traits were found to have statistically significant differences between the plants grown from the irradiated with γ-irradiated seeds and their non-irradiated counterparts. However, the only variety whose mutant plants performed better than the control ones was the field pea variety ‘Dodoni’, even if only for two traits (plant weight and dry biomass). The overall good response of ‘Dodoni’ to this treatment could be studied further to determine whether or not this variety could be enhanced by gamma-irradiated mutagenesis. The studies should be carried out across different locations through multi-year yield trials in order to confirm the potential of mutagenesis [39]. In the same manner, another theme for future research could be the use of other doses of gamma radiation on the edible varieties ‘Early Onward’ and ‘Rondo’, in the hopes of a better response. It is possible that these two varieties will show a different dynamic with an alternative dose use.

Finally, there was no significant difference to be found for the correlation coefficients of agronomic traits between the treatments, and as expected, the performance of the field pea variety was different than that of the edible pea varieties.

Even these initial results can provide valuable information for the early stages of an experiment about induced mutations, such as a variety’s response to radiation. Thus, it is worth researching the M1 generation to strategically design experiments for future mutant generations. In doing so, there will be time- and resource-saving benefits. With our experiment focusing on the M1 generation, there is a future plan to investigate, especially for the ‘Dodoni’ variety, the M2 generation and the following generations in terms of seed quality traits, such as protein content, mineral content, and antioxidant capacity. Moreover, we will study the plants’ tolerance to biotic and abiotic stresses. Additionally, omics approaches could facilitate the identification of mutated loci responsible for a better yield performance.