Food systems are under intense pressure from climate change, which highlights the need for stable crops and varieties that can withstand abrupt soil and environmental changes. It is also important to diversify crops to address increasing yield losses that threaten food security, especially with the growing global population [1]. In addition to concerns about undernourishment, many people are not getting enough micronutrients, which is referred to as “hidden hunger” [2]. In Bangladesh, undernutrition continues to be a serious public health problem. Diversifying the food system is crucial, as climate change poses a threat to human nutrition and food security. One such strategy is the use of quinoa (Chenopodium quinoa Willd.) in our food system which is a highly nutritious and climate-resilient crop species.

Quinoa is known as a miracle crop for its great adaptation in diverse edaphic conditions. A dicotyledonous plant (C₃), quinoa is a member of the Amaranthaceae family. It yields achene fruits, often known as chenopod grains, which have spherical seeds measuring 1.5–4 mm [3]. With ecotypes growing well at high elevations and in poor soils where other cereal crops, like wheat, rice, and maize, do not grow well, the quinoa plant’s extensive genetic diversity enables it to be highly resistant to cold, salt, and drought conditions [4]. While quinoa is becoming more and more popular as a food source globally, Andean indigenous communities have been consuming it for thousands of years [5]. Quinoa is frequently called a “superfood” because of its high nutritional content and resilience to stress. Because of its characteristics that resemble those of cereal grains like corn, wheat, and rice, quinoa is wrongly thought to be pseudo-cereal; in reality, it is categorized as a dicot [6]. The quinoa seed has been eaten in a variety of forms, including flour in baked and toasted foods (bread, noodles, biscuits, cookies, flakes, pancakes, and tortillas) and in breakfast cereals. Furthermore, quinoa is a very nutrient-dense food that includes a range of minerals (like calcium, iron, potassium, potassium, copper, magnesium, and zinc), vitamins (like A, B₁, B₂, B₃, B₅, B₆, B₉, C, and E), dietary fiber, natural antioxidants like polyphenols, and high-quality protein with a high concentration of essential amino acids (reviewed in Ain et al. [7]). Quinoa is processed using particular technologies to address specific health issues in people, like improving fitness, losing weight, celiac disease, and other metabolic issues like diabetes, obesity, hypertension, and hyperlipidemia [8]. After being rediscovered in the latter part of the 20th Century, quinoa has been studied and distributed to more than 120 nations worldwide [5]. Due to its exceptional nutritional value and balance, as well as its remarkable adaptability to a variety of unfavorable conditions like salt and drought, it is anticipated to become a key player in the global solution to food and nutrition issues.

Bangladesh is one of the countries that would be most affected by climate change. Climate change has increased the frequency of certain problems such as drought, unpredictable rainfall, high temperatures, sea level rise, and soil salinity that are both directly and indirectly related to agricultural production. Ensuring food security for all is one of the primary concerns that Bangladesh is now confronting. Salinity is a major threat to crop productivity in the southwestern part of Bangladesh affecting 30% of the arable land of the coastal areas [9]. Bangladesh’s rice yield is expected to drop by 33% by 2100 according to the climate change model, but we need to raise rice production by 50% to feed the country’s growing population. Importantly, rice production may fall by 10% due to salinity only by 2050 [10]. Therefore, it is high time to introduce crops like quinoa in Bangladesh to include the non-cultivated land of the southern part of the country under cultivation and increase cropping intensity, which in turn will boost the gross domestic product. Despite being the primary grain in Bangladesh, rice lacks essential nutrients, leading to high rates of malnutrition and micronutrient deficits in women and children [11]. As a result, quinoa can be a helpful addition to rice or other cereals in addressing malnutrition. The goal of quinoa breeding is to create cultivars that can thrive in a variety of agroclimatic zones and have higher grain yields and high-quality components. Nevertheless, not much has been done in Bangladesh to alter its genetic makeup or create a new crop variety. Although a quinoa variety called SAU Quinoa-1 has recently been released, there is currently little information available in Bangladesh regarding the characterization of quinoa for productivity, nutritional quality, and adaptive potential. To develop a variety, breeders need to evaluate a range of cultivars and genotypes to understand the phenotypic and genotypic variability present in the germplasm. In addition, understanding the genetic parameters such as genotypic co-efficient of variation, heritability and genetic advance and inter-relationship among the traits is quinoa essential for its genetic improvement through a reliable selection program. Consequently, an in-depth investigation of quinoa variability in terms of morpho-agronomic and qualitative characteristics is required. Development of improved quinoa variety through appropriate breeding techniques might have a significant impact on nutritional food security and sustainable agricultural production systems as well as to achieve the SDGs. We hypothesize that significant variation is present in the studied quinoa genotypes in terms of morphological, yield, and nutritional quality traits that might be helpful in boosting genetic gain through additional selective breeding. Considering the above issues in mind, the present investigation was thus aimed to (i) characterize exotic quinoa genotypes based on morphological, yield, and nutritional quality traits; and (ii) phenotypic and genotypic dissection of the traits for effective selection to develop new variety for maximizing genetic gain.

Continuous collection, characterization, and evaluation of unknown quinoa genotypes are urgently needed in developing nations like Bangladesh due to the need for high-quality quinoa products and its exceptional tolerance to harsh climates. Characterization and documentation of quinoa genotypes are therefore imperative for current and future quinoa breeders to ensure global food and nutritional security. In the current study, we have studied the adaptive potential of six quinoa genotypes and also characterized these genotypes based on morphological, yield, and nutritional quality traits. Although these physical characteristics are typically impacted by the environment, measurements of morphological attributes offer a straightforward method of evaluating genotype performance under certain growth conditions while also analyzing genetic variation [18]. The current research results identified a significant diversity among the quinoa genotypes concerning various qualitative traits (Table 1). The majority of genotypes exhibited a simple growth habit (Fig. 1), and two genotypes displayed branching from the base, indicating potential genetic differences in plant architecture as their panicle shape became glomerular which further provided higher yield. According to Kir and Temel [19], planting density, nutrition, and other environmental elements all affect the branching habit. Nevertheless, there was diversity in stem color, with most showing green stems while a few displayed yellow ones, indicating potential genetic differences in pigment synthesis pathways. A similar type of phenotypic variation was also reported by Tabatabaei et al. [20] and Coronado et al. [21]. Furthermore, the presence of pigmented axils in all genotypes highlights a common genetic determinant for this trait. Leaf morphology (Fig. 3) across all genotypes in terms of shape was rhomboidal, triangular, and linear, whereas, the margin was entire and dentate. Panicle shape and color also showed diversity, with implications for seed yield and quality (Fig. 4). In a study resembling ours, Sarwar et al. [22] also reported that quinoa plants exhibited an angular yellow-green stem and simple, rhomboidal green leaves. They observed that the panicle shape was intermediate, displaying both glomerular and amaranthiform shapes. Additionally, they also noted that the panicle was green during flowering but turned pink, orange, and yellow at the physiological maturity stage. Similar to our results, variability in inflorescence color was also reported by Voronov et al. [23]. Characteristics variation was also observed in the seed color of the genotypes studied (Fig. 5). Variation in seed color in different quinoa genotypes was also reported by others [24].

Variability in that particular attribute among the available germplasm is necessary in order to use it in a quinoa breeding program. Additionally, the adaptive potentiality of a particular genotype is assayed based on yield under particular agroclimatic conditions. Significant variations were found between the genotypes and attributes under investigation in the current experiment’s analysis of variance viz., DFF, DM, PH, SD, PW, 1000-SW, YPP, AGB, and HI. Significant variability in yield and yield-attributing traits in quinoa was also reported by de Santis et al. [24], Pathan et al. [25], and Toderich et al. [26]. In the present study, DFF ranged from 22.33 to 27.33 days and DM ranged from 74.67–85.00 days. Similar to our results, Manjarres-Hernández et al. [27] and Pathan et al. [25] also reported that flowering and maturity in quinoa range from 68–121 days and 80–106 days, respectively. While de Santis et al. [24], Bhargava et al. [28], Shah et al. [29], and Granado-Rodríguez et al. [30] reported a longer mean DM 129 days (range: 109–163 days), 116 days (range: 95–150 days), 131 days (range: 105–148 days) and 119 days (range: 107 to 135 days) respectively. The genotypes used in our experiment were primarily short-duration genotypes. These short-duration genotypes hold significant potential for developing early-maturing quinoa varieties, which could be advantageous for regions with drought, shorter growing seasons, or for achieving multiple cropping cycles within a year. The PH of the genotypes ranged from 81.07 to 101.54 cm. This finding is similar to the observation of Granado-Rodríguez et al. [30] who also found that the PH ranged from 60 to 135 cm. Additionally, the studies by Coronado et al. [21], Bhargava et al. [28], Coronado et al. [31], and Laki et al. [32] also support this result demonstrating similar range and mean of PH. The SD of the current study ranged from 6.54 to 10.84 mm. Similar to our results, Tang et al. [33] also reported that stem thickness ranges from 9.64–10.72 mm in low-, medium-, and high-yielding genotypes. Therefore, the variability in PH and SD further highlighted distinct growth patterns among genotypes, with GPBQ-1 demonstrating the tall stature and thickest stems, and GPBQ-2 showing the short stature and smallest dimensions, indicating potential differences in resource allocation and yield potentiallity. The genotypes differed significantly in PW and AGB. Panicle weight ranged from 10.87 to 30.69 g, while AGB ranged from 19.66 to 61.74 g. Bhargava et al. [28] also found that the AGB ranged from 1.11 to 52.89 g. The thousand seed weight of the genotypes varied from 2.29 to 4.61 g, which was similar with the findings of Coronado et al. [21], Sarwar et al. [22], Bhargava et al. [28], Granado-Rodríguez et al. [30] and Craine et al. [34]. The harvest index (HI) of the genotypes ranged from 48.31% to 50.68%, which was higher than the mean HI reported by Laki et al. [32] and Rojas [35], and they showed that the HI ranged from 34% to 40%, respectively. Quinoa typically exhibits low average HI values, as noted by Bertero et al. [36]. The higher HI observed in the genotypes indicates a greater proportion of biomass is allocated to seed yield, suggesting higher economic efficiency. A significant variation in YPP was found in the genotypes which ranged from 7.80 to 22.40 g which was similar to the results reported by Shah et al. [29] and Manugade et al. [37] where YPP mean were 19.86 and 15.00 g, respectively. In contrast, de Santis et al. [24], Bhargava et al. [28] and Craine et al. [34] reported much lower mean YPP of 4.06, 5.51 and 6.33 g, respectively. These findings suggest the presence of high-yielding genotypes in our study, which could be valuable for selection programs aimed at breeding improvements and the development of high-yielding quinoa varieties.

The existence of genetic diversity and the patterns of inheritance of the desired traits are critical to crop breeding success. Analyzing genetic variation is crucial for breeders as it enables them to identify suitable breeding schemes and selection criteria for improving target traits. Therefore, generally, the phenotypic variance is larger than the genotypic variance. A similar statement was also given by Al-Naggar et al. [38] that PCV was a little higher than GCV for all studied traits. Higher heritability and less environmental effect on the expression of a particular trait were indicated by a low difference between genotypic and phenotypic variance. The PCV was marginally greater than the GCV for the majority of the characteristics examined in this study, indicating that environmental influences have little effect on trait expression. Importantly, SD, PW, 1000-SW, YPP and AGB displayed the highest values for both PCV and GCV, indicating considerable potential for genetic improvement in these traits through selection.

Heritability estimations aid in the selection of plants by breeders according to phenotypic performance. Genetic gains in succeeding generations are generally higher in cases of higher heritability. A high heritability also suggests a high degree of genetic control over the particular trait, which aids in the efficient selection of a particular trait for future development [39,40]. For the majority of the traits in the current study, the estimated heritability ranged from 90 to 100 percent (Table 3). This indicated that the environment had little effect on the traits under study, which are mostly controlled by genetics. The GA, a measure of the potential for genetic improvement, varied across traits, with AGB exhibiting the highest value and 1000-SW the lowest. When expressed as a percentage of the mean, GA ranged from 7.29% to 94.74%, with YPP showing the highest value and HI the lowest. High heritability (>60%) coupled with high genetic advance (>20%) was recorded for YPP, AGB, PW, SD and 1000-SW. In quinoa, other people have experienced similar outcomes [24,28]. Since the expression of these attributes is greatly influenced by genetic constitution, this data implies that genetic improvement of these traits is extremely likely and that selection based on phenotypic expression may be a useful tactic.

The correlation coefficient analysis reveals the intricate relationships among various yield and yield-contributing traits (Table 4). The correlation analysis underscores the significance of YPP to various crucial traits. YPP exhibited significant positive correlations with DFF, DM, PH, SD, PW, and AGB (0.568*, 0.812***, 0.744***, 0.895***, 0.993***, 0.985***, respectively), whereas, it showed significant negative correlation with 1000-SW (−0.715***). Positive associations imply that an increase in YPP corresponds to increases in these traits, suggesting a potentially synergistic relationship that contributes to overall yield enhancement. Similar to our results, de Santis et al. [24], and Bhargava et al. [28] reported a significant positive correlation between YPP, DFF and PH. de Santis et al. [24] and Bhargava et al. [28] shed light on the importance of morphological traits such as DFF, DM, PH, 1000-SW, leaf area, branches plant⁻¹, inflorescence length, inforesence plant⁻¹ and harvest index in influencing grain yield in quinoa genotypes. This suggests that genotypes with taller plants are likely to produce higher grain yields in quinoa cultivation. Pathan et al. [25] reported a similar finding with ours that yield had positive correlation with DM and PH. Furthermore, there was a significant negative correlation observed between YPP and 1000-SW, suggesting that as YPP increases, there is a tendency for 1000-SW to decrease. This negative correlation suggests a trade-off scenario where increasing yield per plant may lead to a reduction in individual seed size, this is the opposite of de Santis et al. [24], studies. Thus, the genotypes with greater PH, SD, and ABG, as well as early flowering and maturity, should be chosen in order to increase yield in quinoa breeding, according to the aforementioned findings.

The PCA conducted on the quantitative traits of six quinoa genotypes yielded insightful findings. The PCA unveiled two components, collectively explaining 85.5% of the total variation among the studied traits. Notably, the first two components accounted for a significant portion of this variability, cumulatively explaining 85.5%. Manjarres-Hernández et al. [27] and Wu et al. [41] found that 59.26% to 64.6% of the observed phenotypic variation is explained by the first two components. The first component, responsible for 69.5% of the variance, underscored the substantial positive influence of traits like PW and YPP, indicating their pivotal roles in shaping overall trait variability. Traits such as 1000-SW and HI exhibited negative loadings on this component. This suggests that as YPP increases, there may be a tendency for 1000-SW and HI to decrease, implying a possible trade-off scenario between YPP and individual seed size. The second component, contributing 16% to the total variation, emphasized the significance of traits such as DFF and 1000-SW in further delineating trait variability among the studied genotypes. These findings offer valuable insights into the underlying relationships among the traits and their contributions to overall trait diversity within quinoa genotypes. By elucidating the role of these specific traits in shaping trait variability, the PCA results provide a deeper understanding of the complex dynamics governing trait expression and variability in quinoa populations.

Mineral contents (viz., Ca²⁺, Cu²⁺, Fe²⁺, K⁺, Mg²⁺, Mn²⁺, and Zn²⁺) measured in the quinoa genotypes showed significant variations which indicates a substantial diversity in mineral accumulation within the quinoa varieties under evaluation. Consistent with our findings, significant differences in the mineral contents of quinoa grains were also observed by Nowak et al. [42] and de Bock et al. [43]. Moreover, similar variability was also mentioned by others [28,43–45], where they quantified a large variation in micronutrients levels like Ca²⁺ (275 to 1487 mg kg⁻¹), Cu²⁺ (2 to 51 mg kg⁻¹), Fe²⁺ (14 to 168 mg kg⁻¹), Mg²⁺ (260 to 5020 mg kg⁻¹), K⁺ (75 to 12000 mg kg⁻¹), and Zn²⁺ (28 to 48 mg kg⁻¹) in various diverse quinoa genotypes of geographical origin.

The examination of proximate composition (Fig. 6) in the studied quinoa genotypes revealed uniformity across various nutritional components, including carbohydrate (68.21%–68.83%), protein (14.12%–14.87%), fat (6.37%–6.61%), and fiber content (3.15–3.48%). Similar to our results, Pedrali et al. [46], Agarwal et al. [47] and Oustani et al. [48] also reported that carbohydrate content in quinoa genotypes ranged from 55%–77%, protein content ranged from 13%–19%, fat content ranged from 5%–8% and soluble dietary fiber content ranged from 1.3%–4.1%. These nutritional indices did not significantly differ across the cultivars under study, despite phenotypic diversity. This consistency in grain composition aligns with previous studies that have also reported minimal variability in protein and lipid content among different quinoa genotypes by Repo-Carrasco-Valencia et al. [44] and Pedrali et al. [46] however, they have reported significant differences in carbohydrate and fiber content. The insignificant differences in proximate composition among genotypes suggest a high level of stability in the nutritional quality of quinoa grains, which is advantageous for consumers seeking consistent nutritional benefits [49]. However, further research investigating a broader range of genotypes and environmental conditions may provide deeper insights into the factors influencing quinoa grain composition.

The assessment of B-vitamin complexes showed less variability across the studied quinoa genotypes. B₁, B_2, B_3, and B₉ content showed non-significant differences among the genotypes. The amount of B₃ content ranged from 1.05–1.21 mg/100 g. Similar to our results, Kozioł [50] also reported 1.06 g 100 g⁻¹ of B₃ content in quinoa. Importantly, B₉ content was higher as compared to the others which ranged from 6.45–6.87 mg 100 g⁻¹. Similar to our results, Agarwal et al. [47] also reported 6.50 mg 100 g⁻¹ of B₉ content in quinoa. These findings suggest that quinoa is a rich source of essential B-vitamin complex which is vital for various physiological functions.

A class of natural substances called saponins is generated by certain plants to guard against insects, birds, and hazardous microbes [51]. Researchers reported the presence of saponin, an anti-nutritional substance causing bitterness in quinoa, across different quinoa varieties (reviewed in Suárez-Estrella et al. [52]). In quinoa, these substances are mostly found in the husk. Our study also reported the presence of varying degrees of saponin content among the tested quinoa genotypes, GPBQ-3 contained the lowest amount content of saponin content while SAU Quinoa-1 showed the highest amount of saponin (Fig. 7). Significant variation in saponin content in quinoa genotypes was also reported by others [53]. In another study, Diaz-Valencia et al. [54] reported that quinoa grains contain about 0.00%–4.4% saponins. Although it has been considered as antinutritional fact, recent studies reported that saponin has some positive roles for human health. El Hazzam et al. [55] concluded that quinoa saponins have many important nutritional characteristics such as anticancer, antiobesity, analgesic, hypocholesterolemic, antiallergic, and antioxidants.

Significant variability was observed among the studied qualitative (viz., GH, PSC, PS, PCM, and SC) as well as quantitative traits (viz., DFF, DM, PH, SD, PW, 1000-SW, YPP, AGB, and HI) which offers ample scope of improvement of quinoa for yield and quality. Few of the studied genotypes (viz., GPBQ-1, GPBQ-3, and GPBQ-4) showed better yield performance as compared to the commercial varieties. For the majority of the characteristics under study, PCV was found to be marginally greater than GCV, indicating that environmental influences had little effect on trait expression. The highest values for PCV and GCV were shown by SD, PW, 1000-SW, YPP, and AGB, suggesting significant potential for selection-based genetic improvement in these variables. High h²_b coupled with high GA% was recorded for SD, PW, 1000-SW, YPP, and AGB which indicates that improvement could be made in the aforesaid characters. YPP showed a significant positive correlation with DFF, DM, PH, SD, PW, and AGB (0.568*, 0.812***, 0.744***, 0.895***, 0.993***, 0.985***, respectively). This suggests that increased YPP could be achieved by proper selection pressure. According to PCA analysis, the first three PCs accounted for 85.5% of the genotypes’ overall variation. Significant variation was also observed among the genotypes for vitamins and mineral contents, however, a non-significant variation was observed for carbohydrate, protein, fat, and fiber contents. Considering all the traits, the genotypes GPBQ-1, GPBQ-3, and GPBQ-4 can be considered as potential in terms of yield and others. According to the findings of our research, quinoa can be added to the cropping systems as a new winter crop in Bangladesh. However, further research should be conducted under variable agroclimatic conditions in Bangladesh to study their stability and suitability for release as a new variety.