International Journal of Horticulture 2025, Vol.15, No.1 http://hortherbpublisher.com/index.php/ijh © 2025 HortHerb Publisher, registered at the publishing platform that is operated by Sophia Publishing Group, founded in British Columbia of Canada. All Rights Reserved.
International Journal of Horticulture 2025, Vol.15, No.1 http://hortherbpublisher.com/index.php/ijh © 2025 HortHerb Publisher, registered at the publishing platform that is operated by Sophia Publishing Group, founded in British Columbia of Canada. All Rights Reserved. Publisher HortHerb Publisher Edited by Editorial Team of International Journal of Horticulture Email: edit@ijh.hortherbpublisher.com Website: http://hortherbpublisher.com/index.php/ijh Address: 11388 Stevenston Hwy, PO Box 96016, Richmond, V7A 5J5, British Columbia Canada International Journal of Horticulture (ISSN 1927-5803) is an open access, peer reviewed journal published online by HortHerb Publisher. The journal publishes all the latest and outstanding research articles, letters and reviews in all aspects of horticultural and its relative science, containing horticultural products, protection; agronomic, entomology, plant pathology, plant nutrition, breeding, post harvest physiology, and biotechnology, are also welcomed; as well as including the tropical fruits, vegetables, ornamentals and industrial crops grown in the open and under protection. HortHerb Publisher is an international Open Access publisher specializing in horticulture, herbal sciences, and tea-related research registered at the publishing platform that is operated by Sophia Publishing Group (SPG), founded in British Columbia of Canada. All the articles published in International Journal of Horticulture are Open Access, and are distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. HortHerb Publisher uses CrossCheck service to identify academic plagiarism through the world’s leading plagiarism prevention tool, iParadigms, and to protect the original authors’ copyrights.
International Journal of Horticulture (online), 2025, Vol. 15, No.1 ISSN 1927-5803 http://hortherbpublisher.com/index.php/ijh © 2025 HortHerb Publisher, registered at the publishing platform that is operated by Sophia Publishing Group, founded in British Columbia of Canada. All Rights Reserved. Latest Content Evaluation and Introduction Performance of Five Fresh-Eating Potato Varieties in Changxing County Chunmei Zhu, Yunlong Mao International Journal of Horticulture, 2025, Vol. 15, No. 1, 1-7 Impact of Sugar and Organic Acid Metabolism on Pitaya Flavor and Nutritional Quality Jungui Xu, Tianhui Shi, Zizhong Wang, Yuxin He, Zhen Liu International Journal of Horticulture, 2025, Vol. 15, No. 1, 8-20 Evaluation of Growth and Yield Characteristics of Strawberry (Fragraria ananassa) Varieties in Low Chilling Condition of Chitwan, Nepal Bishal Shrestha, Kalyani Mishra Tripathi, Arjun Kumar Shrestha, Rajendra Gautam International Journal of Horticulture, 2025, Vol. 15, No. 1, 21-28 Case Study on the Application of Innovative Cultivation Techniques in Cucumber Production Fei Yang, Qianlu Gu, Wentao He, Decheng Hong, Mengyan Yu, Jinxiao Yao International Journal of Horticulture, 2025, Vol. 15, No. 1, 29-40 Case Study on High-Yield Fresh-Eating Sweet Potato Varieties: Cultivation Practices in Subtropical Regions Xihu Li, Chai Lin International Journal of Horticulture, 2025, Vol. 15, No. 1, 41-50
International Journal of Horticulture, 2025, Vol.15, No.1, 1-7 http://hortherbpublisher.com/index.php/ijh 1 Research Report Open Access Evaluation and Introduction Performance of Five Fresh-Eating Potato Varieties in Changxing County Chunmei Zhu1,2, Yunlong Mao1,2 1 Changxing Heping Hanxiangmi Family Farm, Huzhou, 313103, Zhejiang, China 2 Zhejiang Agronomist College, Hangzhou, 310021, Zhejiang, China Corresponding author: 361822731@qq.com International Journal of Horticulture, 2025, Vol.15, No.1 doi: 10.5376/ijh.2025.15.0001 Received: 02 Nov., 2024 Accepted: 30 Dec., 2024 Published: 15 Jan., 2025 Copyright © 2025 Zhu and Mao, This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Preferred citation for this article: Zhu C.M., and Mao Y.L., 2025, Evaluation and introduction performance of five fresh-eating potato varieties in Changxing County, International Journal of Horticulture, 15(1): 1-7 (doi: 10.5376/ijh.2025.15.0001) Abstract This study evaluated the field growth performance, yield, tuber characteristics, and culinary quality of five fresh-eating potato (Solanum tuberosumL.) varieties—‘Zheshu956’, ‘Mira’, ‘Zheshu974’, ‘Zheshu927’, and ‘Zheshu926’—in Changxing County. The results showed that ‘Zheshu956’ and ‘Mira’ exhibited vigorous growth, rapid emergence, strong disease resistance, and high yields exceeding 30 000 kg/hm², with excellent culinary qualities, making them suitable for fresh consumption and large-scale promotion. ‘Zheshu974’ had smaller but uniform tubers, slightly lower yield, but good market potential. ‘Zheshu927’ and ‘Zheshu926’ had weaker growth, lower yields, and poor adaptability, making them unsuitable for promotion. Based on a comprehensive analysis, ‘Zheshu956’ and ‘Mira’ are the preferred varieties for Changxing County, while ‘Zheshu974’ may be promoted as a specialty variety. In contrast, ‘Zheshu927’ and ‘Zheshu926’ have limited commercial value. This study provides a scientific basis for potato variety selection in Changxing County and offers a reference for the cultivation and promotion of fresh-eating potatoes in Zhejiang Province. Keywords Potato (Solanum tuberosumL.); Changxing county; Variety introduction; Variety evaluation; Yield; Promotion 1 Introduction Potato (Solanum tuberosumL.) is the world's fourth-largest food crop, following wheat, rice, and maize. With an annual global production exceeding 374 million tons, it plays a crucial role in global agricultural production and human nutrition (Beals, 2019; Gupta and Gupta, 2019). As China continues to adjust its agricultural structure and promote diversified cropping systems, potato cultivation has expanded in southern regions. However, due to traditional farming practices, market demand, and varietal adaptability, large-scale potato production has not yet been fully established in many areas. To optimize cultivation models and improve both yield and quality, it is essential to select suitable potato varieties based on local natural conditions and evaluate their field performance through trials to guide regional promotion (Shen et al., 2018). Changxing County is located in northern Zhejiang Province and has a subtropical monsoon climate with four distinct seasons and synchronized rainfall and heat. The annual average temperature is 15.6 °C, with an annual precipitation of 1 300 mm and a frost-free period of up to 240 days (Wang et al., 2022). These climatic conditions provide favorable conditions for spring potato cultivation, particularly with moderate temperatures and sufficient moisture that promote tuber growth and development (Pandey and Kumar, 2017). Despite these advantages, local potato production faces several challenges. It is predominantly small-scale and scattered, lacking systematic varietal selection and cultivation techniques, resulting in low productivity and limited economic benefits. The coexistence of multiple varieties with varying adaptability has led to inconsistent yields and reduced market competitiveness. In this context, introducing high-quality fresh-eating potato varieties and evaluating their local performance is critical for improving production efficiency and promoting large-scale cultivation. In recent years, China has prioritized food security strategies and implemented farmland restoration policies to address the ‘non-grainization’ phenomenon, ensuring that cultivated land is used for food production (Zhou and Song, 2016). Changxing County actively responds to policies and will launch a "non-grainization" campaign for
International Journal of Horticulture, 2025, Vol.15, No.1, 1-7 http://hortherbpublisher.com/index.php/ijh 2 cultivated land by the end of 2023, adjusting some facility agricultural land and introducing suitable grain crops for experimental demonstration. Potato, as a high-yield and highly adaptable crop, becomes an ideal experimental subject in this context. Selecting fresh potato varieties suitable for local cultivation can not only improve the utilization rate of arable land, but also expand the development path of local agriculture, providing farmers with more economically valuable planting choices (Khalid et al., 2019; Kant et al., 2020). Based on the agricultural production needs of Changxing County, this study selected five fresh-eating potato varieties for a field comparison trial, systematically evaluating their growth characteristics, yield performance, tuber traits, and culinary quality to identify high-yield and high-quality varieties suitable for local promotion. The results of this study will provide a scientific basis for selecting potato varieties for cultivation in Changxing County and surrounding areas, offer theoretical support for optimizing cultivation models, and promote the scaled development of the fresh-eating potato industry. 2 Results and Analysis 2.1 Yield performance of tested varieties The five potato varieties exhibited significant differences in yield performance at the experimental site. Among them, ‘Zheshu956’ had the highest yield, with a plot yield of 27.16 kg, corresponding to a converted yield of 31 055.55 kg/ha. ‘Mira’ followed closely, with a yield of 30 621.00 kg/ha, demonstrating strong yield stability. The yield of ‘Zheshu974’ was 27 876.75 kg/ha, slightly lower than ‘Zheshu956’ and ‘Mira,’ but its smaller tubers were more abundant, making it suitable for specific market demands. ‘Zheshu927’ and ‘Zheshu926’ had yields of 23 657.55 kg/ha and 23 668.95 kg/ha, respectively, both significantly lower than the other varieties, indicating weaker yield potential (Table 1). Table 1 Yield and field performance of 5 tested potato varieties Variety Plot yield (kg) Yield (kg/ha) Field performance Zheshu956 27.16 31055.55 Early emergence,vigorous growth Zheshu927 20.69 23657.55 Average growth Zheshu974 24.38 27876.75 Good growth Zheshu926 20.70 23668.95 Poor growth Mira 26.78 30621.00 Growing vigorously Note: Plot area= 8.75 m2 From the yield data, ‘Zheshu956’ and ‘Mira’ not only exhibited high yields but also maintained stable growth throughout the growing season, indicating strong environmental adaptability. Although ‘Zheshu974’ had a slightly lower yield, its smaller but more numerous tubers catered to higher market demand. In contrast, ‘Zheshu927’ and ‘Zheshu926’ had lower yields and weaker field performance, making them unsuitable for large-scale promotion in Changxing County. 2.2 Field growth performance All tested varieties successfully emerged after sowing, but there were noticeable differences in emergence timing and rate. ‘Zheshu956’ and ‘Mira’ emerged earlier, displayed vigorous growth, expanded leaves rapidly, and achieved high field coverage, demonstrating good adaptability. ‘Zheshu974’ emerged slightly later but maintained balanced growth and overall strong field performance. In contrast, ‘Zheshu927’ and ‘Zheshu926’ had slower emergence, shorter plants, weaker growth, and lower field coverage (Table 1; Figure 1). During plant growth, the tested varieties exhibited differences in plant height, branching patterns, leaf color, and disease resistance. ‘Zheshu956’ and ‘Mira’ had taller plants, more branches, broad and dark green leaves, and vigorous growth, showing strong resistance to diseases. ‘Zheshu974’ had moderate plant height, a balanced number of branches, and slightly lighter leaf color but maintained uniform growth. In contrast, ‘Zheshu927’ and ‘Zheshu926’ were shorter, had fewer branches, smaller leaves, and weaker overall growth. These varieties were more susceptible to disease during the trial period, indicating lower resistance.
International Journal of Horticulture, 2025, Vol.15, No.1, 1-7 http://hortherbpublisher.com/index.php/ijh 3 Figure 1 Field performance of 5 tested potato varieties Note: A: Zheshu956, B: Mira, C: Zheshu974, D: Zheshu926, E: Zheshu927 These results suggest that ‘Zheshu956’ and ‘Mira’ respond well to water and fertilizer management, maintaining stable growth and demonstrating good adaptability to the climatic conditions of Changxing County. On the other hand, ‘Zheshu927’ and ‘Zheshu926’ were more sensitive to environmental changes, making them susceptible to adverse weather conditions, which led to uneven growth and further affected yield. 2.3 Tuber characteristics evaluation The experimental results showed that the tubers of ‘Zheshu956’ and ‘Mira’ were relatively large, long-oval in shape, with smooth skin and shallow eyes, exhibiting high commercial value. The tubers of ‘Zheshu974’ were smaller but uniform in shape, making it suitable for promotion as a small fresh-eating potato variety. ‘Zheshu927’ had pink skin and pink flesh with a rounder shape, but the tuber size was uneven, resulting in weaker market competitiveness. ‘Zheshu926’ had medium-sized tubers with an ordinary appearance and showed average overall performance (Table 2). The depth of the tuber eyes affects the ease of processing and peeling. ‘Zheshu956’ and ‘Mira’ had shallow eyes, making them easier to process, whereas ‘Zheshu927’ had deeper eyes, potentially limiting its market competitiveness. Overall, the tuber traits of ‘Zheshu956,’ ‘Mira,’ and ‘Zheshu974’ were superior, providing them with a stronger market advantage. Table 2 Quality performance of 5 tested varieties Variety Tuber properties Skin color Flesh color Potato shape Zheshu956 Yellow Yellow Long-round Zheshu927 Pink Pink Round Zheshu974 Yellow Yellow Round Zheshu926 Yellow Yellow Round Mira Yellow Yellow Long-round 2.4 Cooking quality and taste evaluation The steaming test revealed noticeable differences in taste among the tested varieties. ‘Zheshu956’ had a powdery texture after steaming, with a rich potato aroma and good palatability, making it well-suited for fresh consumption. ‘Mira’ exhibited a balanced texture of powdery and waxy, with a pronounced aroma and overall excellent eating
International Journal of Horticulture, 2025, Vol.15, No.1, 1-7 http://hortherbpublisher.com/index.php/ijh 4 quality. ‘Zheshu974’ was relatively powdery, with a strong aroma, making it suitable for certain culinary applications. ‘Zheshu927’ had a waxy texture after steaming but carried a slight off-flavor, which could affect its market acceptance. ‘Zheshu926’ had a moderate powdery texture and acceptable taste but showed an overall average performance (Table 3). Based on their cooking quality, ‘Zheshu956’ and ‘Mira’ are the most suitable for promotion as high-quality fresh-eating potatoes, while ‘Zheshu974’ is more appropriate for the mini potato market. Due to their inferior taste, ‘Zheshu927’ and ‘Zheshu926’ are not recommended for promotion. Table 3 Cooking taste and comprehensive evaluation of 5 tested varieties Variety Cooking taste Comprehensive evaluation Zheshu956 Powder, strong flavor of potato, good taste High yield and good taste; suitable for large-scale demonstration and promotion in Changxing Zheshu927 Waxy, off-flavor, poor taste Pink skin and pink flesh, but poor growth, low yield poor taste; eliminated Zheshu974 Powdery, good taste Relatively high yield, small and numerous tubers; suitable for demonstration as mini potatoes Zheshu926 Powder, good taste Good taste, but poor growth and low yield; eliminated Mira Powder with waxy, strong flavor of potato, good taste High yield, good taste, which can be widely promoted in Changxing 2.5 Comprehensive variety evaluation Based on field growth performance, yield, tuber characteristics, and taste evaluation, ‘Zheshu956’ and ‘Mira’ demonstrated the best overall performance and high promotion potential. Both varieties exhibited high yields, excellent tuber appearance, superior culinary quality, and strong adaptability, making them well-suited for large-scale cultivation in Changxing County (Table 3). ‘Zheshu974’ had smaller tubers but achieved relatively high yields, making it suitable for promotion as a mini potato variety. In contrast, ‘Zheshu927’ and ‘Zheshu926’ exhibited weaker field performance, lower yields, and average culinary quality, indicating they are not suitable for widespread cultivation in Changxing County. Overall, ‘Zheshu956’ and ‘Mira’ are the preferred varieties for spring potato cultivation in Changxing County and are recommended for adoption by local farmers. Further optimization of their cultivation management techniques could enhance their yield and quality, increasing their market competitiveness. 3 Discussion This study evaluated the field growth performance, yield, tuber characteristics, and culinary quality of five fresh-eating potato varieties in Changxing County. The results showed significant differences in adaptability and yield among the varieties. ‘Zheshu956’ and ‘Mira’ exhibited early emergence, vigorous growth, strong plant structure, high field coverage, and good disease resistance, demonstrating strong yield stability. ‘Zheshu974’ had balanced growth, smaller but uniform tubers, making it suitable for specific market demands. ‘Zheshu927’ and ‘Zheshu926’ showed weaker growth, were more susceptible to diseases, had lower yields, and had limited promotion potential. The findings of this study align with research on the introduction of 21 potato varieties in Wenzhou (Ye et al., 2024) and the field performance of ‘Zheshu956’ in Jinhua (Jiang et al., 2022). These studies also demonstrated that ‘Zheshu956’ has good adaptability and high yield potential in Zhejiang Province. For example, in Jinhua, ‘Zheshu956’ achieved an average yield of 2 646.1 kg/mu (approximately 39 667.2 kg/ha), which was higher than the yield observed in this study. This difference may be attributed to variations in climate, soil fertility, and cultivation practices. The wide-row, narrow-plant, high-ridge mulching system adopted in Jinhua may have contributed to higher yields, suggesting that the cultivation approach used in this study still has room for optimization in terms of water and nutrient management or planting density.
International Journal of Horticulture, 2025, Vol.15, No.1, 1-7 http://hortherbpublisher.com/index.php/ijh 5 Field trials in Jinhua and Wenzhou have also shown that ‘Zheshu956’ has good late blight resistance, with lower tuber rot rates compared to control varieties (Jiang et al., 2022; Shen et al., 2019; 2024). This study did not specifically investigate late blight resistance, but field observations indicated no significant disease outbreaks among the tested varieties. This could be attributed to the relatively dry climate at the experimental site, which reduced pathogen pressure. Future research should integrate field disease monitoring with molecular marker analysis to provide a more comprehensive evaluation of disease resistance, which could strengthen recommendations for variety promotion. In terms of market adaptability, ‘Zheshu 974’ had a high proportion of small tubers, meeting the demand for mini-sized fresh potatoes in certain markets. This characteristic aligns with the traits of Zhejiang’s local potato germplasm, which is generally biased toward smaller tubers with excellent steaming quality (Shen et al., 2018; 2019). ‘Zheshu927’, with its red skin and red flesh, has potential in the niche market for colored potatoes (Ye et al., 2024). However, in Wenzhou trials, ‘Zheshu927’ showed slightly higher yields than ‘Zheshu934’, but it still ranked in the mid-range, indicating that the promotion of colored potatoes in Zhejiang may require further optimization of cultivation strategies to enhance yield stability. The results of this study are relatively clear, but there are still certain limitations. This trial was conducted at a single site, preventing the assessment of how annual climate variations affect variety adaptation. Additionally, the study did not explore different cultivation methods (such as planting density or fertilization strategies), which could influence the overall evaluation of variety suitability. Sensory evaluation was used for taste testing, which may be subject to subjective bias; future studies could incorporate physicochemical analyses to better quantify quality characteristics. Despite these limitations, this study provides a valuable reference for potato variety selection and promotion in Changxing County. ‘Zheshu956’ and ‘Mira’ demonstrated high yield potential, superior quality, and strong adaptability, making them suitable for large-scale promotion. ‘Zheshu974’, with its small and uniform tubers, is suitable for the mini fresh potato market and could be promoted as a specialty variety. ‘Zheshu927’ and ‘Zheshu926’ performed poorly in the field, making them less suitable for widespread cultivation. Future research should expand the scope of trials with multi-year, multi-location experiments to validate the stability and environmental adaptability of these varieties. The impact of different cultivation management measures, such as fertilization strategies and dense planting patterns, on yield and quality also needs further exploration to provide more accurate cultivation recommendations for variety promotion. Integrating molecular breeding techniques could help identify the genetic mechanisms underlying high yield, quality, and disease resistance, supporting the sustainable development of the potato industry. 4 Materials and Methods 4.1 Experimental site conditions This experiment was conducted in the spring of 2024 at Heping Hanxiangmi Family Farm in Dongshan Village, Heping Town, Changxing County, Zhejiang Province, located near National Highway S306. The previous crop at the site was greenhouse-grown grapes. Due to long-term grape cultivation, the soil has undergone extensive management, resulting in high fertility levels. The soil type is sandy loam, which provides good drainage and is conducive to potato growth and tuber development. During the trial period, the temperature at the sowing stage (mid-January) was relatively low but still met the requirements for potato germination. As temperatures increased in spring, the environmental conditions became favorable for tuber formation and enlargement. Overall, this region offers a suitable climatic foundation for conducting spring potato cultivation trials. 4.2 Experimental materials This study selected five fresh-eating potato varieties from different sources, including four newly bred varieties (‘Zheshu956’, ‘Zheshu974’, ‘Zheshu927’, and ‘Zheshu926’) developed by the Institute of Crop and Nuclear Technology Utilization, Zhejiang Academy of Agricultural Sciences, and the virus-free seed tubers of ‘Mira’ introduced from Germany (Table 4). These varieties differ in tuber size, skin color, flesh texture, and cooking quality, necessitating field trials to evaluate their adaptability and production potential.
International Journal of Horticulture, 2025, Vol.15, No.1, 1-7 http://hortherbpublisher.com/index.php/ijh 6 Table 4 Basic information of 5 tested potato varieties Variety name Variety source Variety characteristics Zheshu956 New varieties of ZAAS, No.:GPD Potato(2019)330032 Large tuber, yellow skin and yellow meat Zheshu927 New strains of ZAAS Medium tuber,pink skin and pink flesh Zheshu974 New strains of ZAAS Small and round tuber,yellow skin and flesh Zheshu926 New strains of ZAAS Medium tuber,yellow skin and yellow flesh Mira from Germany,virus-free seed potatoes by ZAAS Long and round tuber, yellow skin and yellow flesh 4.3 Experimental design and management This experiment adopted a randomized block design, with each variety assigned to an independent plot arranged randomly. Border rows were set up around the plots to minimize edge effects. Each plot covered an area of 8.75 m2 (3.5 m × 2.5 m), and no replications were conducted to ensure uniform planting conditions and improve comparability. The experiment commenced on January 17, 2024, using two seed tuber treatments: large tuber cutting (cut according to the bud eye, approximately 30 g per piece, each with 1-2 bud eyes) and small whole tubers (individual weight 20-50 g). Sowing was carried out by furrow planting or hole planting, with row spacing of 60 cm and plant spacing of 35 cm. Each planting hole received one seed tuber, placed with the bud eye facing upward and covered with 5 cm of fine soil. The planting density was approximately 3 200 plants per mu (≈48 000 plants/ha). Field management followed standard potato cultivation practices. Organic fertilizer combined with compound fertilizer was applied as a base fertilizer to improve soil fertility and promote early growth. During the growing season, additional nitrogen fertilizer was applied according to plant growth conditions to support tuber enlargement (Ayyub et al., 2019; Shilev et al., 2022). Irrigation was adjusted based on soil moisture levels to maintain optimal field conditions, preventing both drought stress and excessive moisture, which could negatively affect tuber development. An integrated pest management strategy was implemented to control diseases and pests. Potato virus diseases are primarily transmitted by aphids (Myzus persicae) and, particularly, Potato Apical Leaf Curl Virus (PALCV). The whitefly (Bemisia tabaci), a major vector of PALCV, was targeted using a control strategy combining seed tuber soaking, insect regulation, and mineral oil spraying, which has been shown to reduce aphid populations by 74.5% and lower virus infection rates by 93% (Kamlesh et al., 2020). 4.4 Data collection The potatoes were harvested on April 24, 2024, with a total growth cycle of 128 days. After harvest, systematic measurements were conducted on each variety’s growth performance, yield, and tuber characteristics. Growth parameters included plant height, number of branches, leaf color, and disease resistance to assess overall plant performance. Tuber trait assessments included total yield per plot, converted to yield per hectare, to quantify the production potential of each variety. Additional recorded parameters included tuber size, shape, skin color, and eye depth, providing insights into market acceptability. Furthermore, uniform-sized tubers were selected for steaming tests, where sensory evaluation was conducted to assess powdery texture, aroma, and palatability, offering a basis for determining culinary quality and potential market suitability. Acknowledgments The authors are deeply grateful to Professor R. Cai for his thorough reviews of this manuscript and his insightful revision suggestions. Conflict of Interest Disclosure The authors affirm that this research was conducted without any commercial or financial relationships that could be construed as a potential conflict of interest.
International Journal of Horticulture, 2025, Vol.15, No.1, 1-7 http://hortherbpublisher.com/index.php/ijh 7 References Ayyub C.M., Wasim Haidar M., Zulfiqar F., Abideen Z., and Wright S.R., 2019, Potato tuber yield and quality in response to different nitrogen fertilizer application rates under two split doses in an irrigated sandy loam soil, Journal of Plant Nutrition, 42(15): 1850-1860. https://doi.org/10.1080/01904167.2019.1648669 Beals K.A., 2019, Potatoes, nutrition and health, American Journal of Potato Research, 96(2): 102-110. https://doi.org/10.1007/s12230-018-09705-4 Gupta U.C., and Gupta S.C., 2019, The important role of potatoes, an underrated vegetable food crop in human health and nutrition, Current Nutrition & Food Science, 15(1): 11-19. https://doi.org/10.2174/1573401314666180906113417 Jiang M.Q., Zhang L., Wu L.H., Zhong Z.Y., and Cheng L.R., 2022, Planting performance and cultivation techniques of Zheshu 956 in Jinhua, Zhejiang Nongye Kexue (Journal of Zhejiang Agricultural Sciences), 63(7): 1449-1451,1468. https://doi.org/10.16178/j.issn.0528-9017.20213058 Khalid S., Shaheen S., Ishfaq A., and Siddique R., 2019, Performance study of exotic variety of potato (Solanum tuberosumL.) for processing industry under the agro-climatic condition of Lahore-Pakistan, Pure and Applied Biology (PAB), 8(4): 2262-2268. https://doi.org/10.19045/BSPAB.2019.80172 Kant K., Gupta S.K., Patel A.B., Kumar S., Kumar A., Vishwakarma R., and Sohane R.K., 2020, Influence of varietal replacement demonstration on the yield and economics of potato (Solanum tuberosum) cv. Kufri Pukhraj in Bhagalpur District of Bihar, Journal of Pharmacognosy and Phytochemistry, 9(2): 1758-1761. Kamlesh M., Raghavendra K.V., and Kumar M., 2021, Vector management strategies against Bemisia tabaci (Gennadius) transmitting potato apical leaf curl virus in seed potatoes, Potato Research, 64(2): 167-176. https://doi.org/10.1007/s11540-020-09470-0 Pandey V., and Kumar V.A., 2017, Effective manipulation of potato storage timing enable seed production as summer and winter crop consequently in year, Chemical Science Review and Letters, 6(21): 389-393. Shen S.F., Wu L.H., Xiang C., and Li B., 2019, Identification of potato local germplasm resources in Zhejiang Province, Zhejiang Nongye Kexue (Journal of Zhejiang Agricultural Sciences), 60(1): 83-88. https://doi.org/10.16178/j.issn.0528-9017.20190128 Shen S.F., Wu L.H., Xiang C., Cheng L.R., Zhang L., and Bian X.B., 2024, Breeding and cultivation techniques of fresh potato variety Zheshu 956, Zhejiang Nongye Kexue (Journal of Zhejiang Agricultural Sciences), 65(1): 47-51. https://doi.org/10.16178/j.issn.0528-9017.20220966 Shen S.F., Xiang C., Wu L.H., Cai R.X., Wu Z.G., and Li B., 2018, Identification, evaluation and breeding utilization of local potato varieties in Zhejiang Province, Fenzi Zhiwu Yuzhong (Molecular Plant Breeding), 16(21): 7195-7203. https://doi.org/10.13271/j.mpb.016.007195 Shilev S., Mitova I., Kuncheva V., Dinev N., and Kabaivanova L., 2022, Distribution of soil microorganisms in field under potatoes due to fertilizer and organics, Indian Journal of Agricultural Research, 56(4): 401-407. https://doi.org/10.18805/ijare.a-669 Wang Y.Y., Luo T., Wu L.L., Xu W.H., and Hong X.C., 2022, Climate adaptation assessment on block space compactness:a case study of Changxing, Zhejiang, Jianzhu Yu Wenhua (Architecture & Culture), (2): 148-151. Ye Y.J., Chen Y.Z., Zhang T., Zhang X.L., and Qian R.J., 2024, Introduction performance and growth evaluation of 21 potato varieties(lines) in Wenzhou, Zhejiang Nongye Kexue (Journal of Zhejiang Agricultural Sciences), 65(4): 913-915. Zhou Y.L., and Song Y.Q., 2016, Causes and solving measures of non-food during the process of farmland circulation—From the perspective of national food security, Guangdong Nongye Kexue (Guangdong Agricultural Sciences), 43(1): 189-192.
International Journal of Horticulture, 2025, Vol.15, No.1, 8-20 http://hortherbpublisher.com/index.php/ijh 8 Research Insight Open Access Impact of Sugar and Organic Acid Metabolism on Pitaya Flavor and Nutritional Quality JunguiXu2*, Tianhui Shi 1,3*, Zizhong Wang2,YuxinHe1,3, ZhenLiu1 1 Hainan Institute of Zhejiang University, Sanya, 572024, Hainan, China 2 Hainan Huitian Agriculture Co., Ltd., Sanya, 572024, Hainan, China 3 College of Agricultural & Biotechnology, Zhejiang University, Hangzhou, 310058, Zhejiang, China * These authors contributed equally to this work Corresponding author: zhenliu2012@zju.edu.cn International Journal of Horticulture, 2025, Vol.15, No.1 doi: 10.5376/ijh.2025.15.0002 Received: 03 Nov., 2024 Accepted: 05 Jan., 2025 Published: 26 Jan., 2025 Copyright © 2025 Xu et al., This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Preferred citation for this article: Xu J.G., Shi T.H., Wang Z.Z., He Y.X., and Liu Z., 2025, Impact of sugar and organic acid metabolism on pitaya flavor and nutritional quality, International Journal of Horticulture, 15(1): 8-20 (doi: 10.5376/ijh.2025.15.0002) Abstract This study conducts an in-depth analysis of the role of sugar and organic acid metabolism in the formation of dragon fruit flavor and the enhancement of its nutritional quality. The findings reveal that glucose, fructose, and sucrose are the primary sugars in pitaya, while malic acid and citric acid are the predominant organic acids. The balance between sugars and organic acids significantly influences the sweetness and overall flavor profile of pitaya, with secondary metabolites such as betalains further enriching its sensory attributes. Key genes and transcription factors (e.g., HpDof1.7, HpDof5.4) play critical roles in regulating sugar and acid metabolism, with a notable contribution to sugar accumulation during the fruit maturation stage. The study also examines the regulatory mechanisms of sugar-acid metabolism in relation to genetic background, cultivation practices, and post-harvest handling, emphasizing the importance of interdisciplinary approaches. This study provides scientific guidance for optimizing pitaya breeding and cultivation management, supporting the sustainable development of the pitaya industry, and meeting diverse consumer demands. Keywords Pitaya (Hylocereus spp.); Sugar metabolism; Organic acids; Flavor; Nutritional quality; Quality optimizatio 1 Introduction Pitaya, commonly known as dragon fruit, belongs to the genus Hylocereus and is native to Central America, such as Mexico, El Salvador, Guatemala, and Honduras. The primary species include Hylocereus costaricensis, H. undatus, and H. megalanthus, which are cultivated extensively in tropical and subtropical regions worldwide, including Brazil and Turkey (Constantino et al., 2021; Attar et al., 2022). The fruit is celebrated for its vibrant appearance, sweet taste, and high nutritional value, making it a popular choice for fresh consumption and industrial processing into beverages and desserts (Constantino et al., 2021; Lin et al., 2021). The economic value of pitaya has surged in recent years due to its increasing popularity and demand in both local and international markets (Chapai et al., 2024). The flavor and nutritional quality of pitaya are critical factors that influence its market competitiveness and consumer acceptance. The sweetness and overall taste of the fruit are primary determinants of consumer preference, which directly impacts market demand (Jiang et al., 2023). Additionally, the nutritional profile, including antioxidant capacity and phenolic content, enhances the fruit's appeal as a health-promoting food. High levels of antioxidants and phenolic compounds, particularly in red-fleshed varieties, contribute to the fruit's health benefits and market value (Attar et al., 2022). Therefore, understanding and improving these attributes are essential for maintaining and expanding pitaya's market presence. Sugars and organic acids play pivotal roles in determining the flavor, texture, and nutritional value of pitaya. The primary sugars found in pitaya include glucose, fructose, and sucrose, which contribute to the fruit's sweetness and overall taste profile (Constantino et al., 2021; Xie et al., 2022). Organic acids, such as malic and citric acids, influence the fruit's acidity and flavor balance. The metabolic processes governing the accumulation of these compounds are complex and involve various genes and biochemical pathways (Xie et al., 2022; Jiang et al., 2023).
International Journal of Horticulture, 2025, Vol.15, No.1, 8-20 http://hortherbpublisher.com/index.php/ijh 9 For instance, the HuSWEET family of sugar transporters has been identified as crucial in regulating sugar accumulation during fruit development (Jiang et al., 2023). Additionally, the interplay between sugars, organic acids, and other metabolites, such as betalains, further affects the fruit's quality and visual appeal (Wu et al., 2019). This study systematically explores the impact of sugar and organic acid metabolism on the flavor and nutritional quality of pitaya, focusing on the biochemical traits and metabolic pathways that determine its sensory and nutritional characteristics. The study intends to uncover key factors that enhance the sweetness, overall taste, and health benefits of pitaya. These findings are expected to provide valuable insights for future research and practical applications in pitaya cultivation and processing, ultimately improving its market competitiveness and consumer acceptance. 2 Composition and Metabolism of Sugars in Pitaya 2.1 Analysis of types and content of sugars Pitaya exhibits a diverse composition of sugars that significantly influence its flavor and nutritional quality. The primary sugars identified in various pitaya species include glucose, fructose, and sucrose. For instance, in the yellow-peel pitaya species ‘Wucihuanglong’ (Hylocereus undatus) and ‘Youcihuanglong’ (Hylocereus megalanthus), glucose is the dominant sugar in ‘WCHL’, while ‘YCHL’ contains higher levels of sucrose, fructose, and glucose (Xie et al., 2022; Xu et al., 2024). Hylocereus undatus presents a total sugar content of 9.83%, with glucose and fructose being the major components (Wei et al., 2019; Constantino et al., 2021). The study found that glucose is the primary sugar in mature fruit, followed by fructose, while sucrose content is relatively low and exhibits minimal variation. During the later stages of fruit development (30 to 40 days after artificial pollination), the levels of glucose and fructose significantly increased, reaching 12.2-fold and 6-fold of their initial levels, respectively (Figure 1). In contrast, H. megalanthus has a lower total sugar concentration of 5.93%, with a notable presence of sucrose. Compared to H. polyrhizus, H. undatus has lower total phenolic content and antioxidant potential but stands out in terms of sugar composition. The flesh of H. undatus, with its low acidity and high sugar content, is particularly suitable for making desserts and beverages (Arivalagan et al., 2021). These variations in sugar composition among different pitaya varieties are crucial for determining their sweetness and overall flavor profile. Figure 1 Glucose is the main sugar in mature pitaya fruit. (A) Photograph of pitaya fruit at different developmental stages. (B) Changes of soluble sugars (glucose, fructose, and sucrose) contents during fruit maturation. Fruit at 16, 21, 26, 30, 35, and 40 days after artificial pollination (DAAP) was sampled for analysis. Data represent mean values from three biological replicates (±S.E.) (Adopted from Wei et al., 2019)
International Journal of Horticulture, 2025, Vol.15, No.1, 8-20 http://hortherbpublisher.com/index.php/ijh 10 2.2 Sugar metabolism pathways and key enzymes The metabolism of sugars in pitaya involves several biochemical pathways and key enzymes that regulate the synthesis, breakdown, and transport of sugars. Key enzymes such as sucrose synthase (HpSuSy1) and invertase (HpINV2) play pivotal roles in the hydrolysis of sucrose into glucose and fructose, which are the predominant sugars in pitaya (Wei et al., 2019; Luo et al., 2021). The expression of these enzymes is regulated by transcription factors like HpWRKY3, which activates the transcription of HpSuSy1 and HpINV2, thereby enhancing sugar accumulation during fruit maturation. The SWEET family of sugar transporters, particularly HuSWEET12a and HuSWEET13d, are crucial for sugar transport and accumulation in pitaya fruits. These transporters facilitate the movement of sugars across cell membranes, contributing to the overall sugar content in the fruit (Jiang et al., 2023). The regulatory mechanisms involving Dof transcription factors (HpDof1.7 and HpDof5.4) further modulate the expression of sugar metabolism-related genes, enhancing the activities of HpSuSy1, HpINV2, and sugar transporter genes like HpTMT2 andHpSWEET14 (Mou et al., 2022; Zou and Sun, 2023). 2.3 Influence of sugar metabolism on flavor and sweetness The metabolism of sugars in pitaya significantly impacts its flavor and sweetness, which are critical determinants of fruit quality and consumer preference (Gou et al., 2023). The accumulation of glucose and fructose, facilitated by the activities of HpSuSy1 and HpINV2, directly correlates with the sweetness of the fruit (Wei et al., 2019; Wang et al., 2024). The expression of HuSWEET12a and HuSWEET13d during fruit maturation also contributes to the increased sugar content, enhancing the sweetness and overall flavor profile of pitaya (Xie et al., 2022). Furthermore, the regulatory role of Dof transcription factors in activating sugar metabolic pathway genes underscores the complex interplay between sugar metabolism and flavor development in pitaya (Mou et al., 2022). The balance between different sugars, such as the higher sucrose content in ‘YCHL’ pitaya and the dominant glucose in ‘WCHL’ pitaya, also influences the perceived sweetness and flavor nuances of different pitaya varieties. Thus, understanding the biochemical pathways and regulatory mechanisms of sugar metabolism is essential for improving the flavor and nutritional quality of pitaya fruits. 3 Organic Acid Metabolism in Pitaya 3.1 Types and content of organic acids in pitaya Pitaya fruits contain several organic acids that significantly contribute to their flavor profile. The primary organic acids identified in various pitaya species include malic acid and citric acid. For instance, Hylocereus costaricensis, H. undatus, and H. megalanthus have been reported to contain malic acid concentrations of 0.83%, 0.71%, and 0.62%, respectively, and citric acid concentrations of 0.37%, 0.36%, and 0.40%, respectively (Constantino et al., 2021). Additionally, ascorbic acid (vitamin C) content varies among different pitaya species, with some studies noting its presence in significant amounts during certain developmental stages (Xie et al., 2022). The content of organic acids in pitaya can vary significantly across different varieties and developmental stages. For example, ‘Wucihuanglong’ (Hylocereus undatus) and ‘Youcihuanglong’ (Hylocereus megalanthus) pitayas exhibit different profiles of organic acid accumulation during fruit maturation. 'Wucihuanglong' pitaya has higher ascorbic acid content compared to ‘Youcihuanglong’ pitaya (Xie et al., 2022). Furthermore, the concentration of malic and citric acids also differs, with ‘Wucihuanglong’ primarily accumulating malic acid and ‘Youcihuanglong’ accumulating citric acid. This variability is crucial for breeding programs aimed at enhancing specific flavor profiles and nutritional qualities. 3.2 Enzymatic pathways of organic acid metabolism The metabolism of organic acids in pitaya involves several key enzymes that regulate their synthesis and degradation. Enzymes such as malate dehydrogenase and citrate synthase play pivotal roles in the tricarboxylic acid (TCA) cycle, which is central to organic acid metabolism. Transcriptome analyses have identified numerous
International Journal of Horticulture, 2025, Vol.15, No.1, 8-20 http://hortherbpublisher.com/index.php/ijh 11 genes associated with these metabolic pathways, highlighting their importance in the regulation of organic acid content in pitaya (Yin et al., 2015; Xie et al., 2022). Additionally, enzymes involved in the ascorbate-glutathione cycle, such as ascorbate peroxidase, are crucial for maintaining ascorbic acid levels in the fruit (Li et al., 2018). The regulation of organic acid metabolism in pitaya is complex and involves multiple layers of control, including transcriptional regulation. Studies have shown that the expression of genes involved in organic acid metabolism is tightly regulated during fruit development (Schvartzman et al., 2018). For instance, the expression of genes encoding enzymes like malate dehydrogenase and citrate synthase is modulated in response to developmental cues and environmental factors. Additionally, transcription factors such as WRKY and Dof have been implicated in the regulation of sugar and organic acid metabolism, further highlighting the intricate regulatory networks governing these processes (Wei et al., 2019; Mou et al., 2022). 3.3 Role of organic acids in flavor and acidity Organic acids are key contributors to the tartness and overall flavor profile of pitaya. Malic acid and citric acid, in particular, are responsible for the characteristic tartness of the fruit. The balance between these acids and sugars determines the perceived sweetness and acidity, which are critical factors influencing consumer preference (Constantino et al., 2021). The presence of ascorbic acid also adds a subtle tanginess, enhancing the fruit's flavor complexity (Xie et al., 2022). The balance of organic acids in pitaya significantly affects consumer preference. Fruits with a higher ratio of sugars to organic acids are generally perceived as sweeter and more palatable. For instance, H. undatus, with its higher sugar content and lower acidity, is preferred for fresh consumption and in desserts and beverages (Fernandes et al., 2018; Arivalagan et al., 2021; Singh et al., 2023). Conversely, H. megalanthus, which has a more balanced sugar-acid profile, is recommended for individuals on carbohydrate-restricted diets due to its lower overall sugar content (Constantino et al., 2021). Understanding the interplay between organic acids and sugars is essential for developing pitaya varieties that meet diverse consumer preferences. 4 Interaction between Sugar and Organic Acid Metabolism 4.1 Balance between sugar and acid content The sugar-to-acid ratio is a critical determinant of fruit taste, influencing consumer preferences and overall flavor perception. In pitaya, the balance between sugars such as glucose, fructose, and sucrose, and organic acids like malic and citric acids, plays a significant role in defining the fruit's taste profile (Constantino et al., 2021; Xie et al., 2022). Higher sugar content generally enhances sweetness, while organic acids contribute to tartness, creating a complex flavor profile that is appealing to consumers (Constantino et al., 2021). The specific ratios of these components can vary significantly among different pitaya species and cultivars, affecting their marketability and consumer acceptance. The balance between sugars and acids in pitaya changes dynamically during fruit ripening. Early stages of fruit development are characterized by higher starch accumulation, which is later converted into soluble sugars as the fruit matures. Concurrently, the concentration of organic acids tends to decrease, leading to a sweeter taste in fully ripened fruits (Xie et al., 2022). This shift in sugar-acid balance is crucial for achieving the desired flavor and nutritional quality in pitaya. For instance, fruits harvested at an advanced color stage exhibit higher soluble sugar concentrations and lower acidity compared to those harvested at the color-break stage, resulting in superior taste quality (Hua et al., 2018; Sobral et al., 2019). 4.2 Influence on pitaya’s overall flavor profile The interaction between sugars and organic acids contributes significantly to the complexity of pitaya's flavor profile. Sugars such as glucose and fructose are predominant in mature pitaya, while malic and citric acids are the main organic acids present (Constantino et al., 2021; Xie et al., 2022). This combination of sweet and tart flavors creates a balanced and complex taste that is highly valued by consumers. The presence of other metabolites, such as phenolic compounds and flavonoids, further enhances the flavor complexity by adding additional layers of taste and aroma (Wu et al., 2019; Xie et al., 2022).
International Journal of Horticulture, 2025, Vol.15, No.1, 8-20 http://hortherbpublisher.com/index.php/ijh 12 Consumer preference for pitaya is largely influenced by the sensory perception of its flavor, which is determined by the balance of sugars and acids. Studies have shown that consumers tend to prefer pitaya varieties with higher sugar content and moderate acidity, as these attributes contribute to a more pleasant and palatable taste (Wei et al., 2019; Constantino et al., 2021). The sensory attributes of pitaya, including sweetness, tartness, and overall flavor intensity, are key factors in determining its market acceptance and consumer satisfaction. 4.3 Regulatory mechanisms involved in sugar-acid interactions The metabolism of sugars and organic acids in pitaya is regulated by a complex interplay of genetic and environmental factors. Specific genes, such as those encoding for sugar transporters and metabolic enzymes, play crucial roles in the accumulation and distribution of sugars and acids during fruit development (Wei et al., 2019; Mou et al., 2022; Jiang et al., 2023). Environmental conditions, including temperature and storage conditions, also significantly impact the sugar-acid balance in pitaya. For example, fruits stored at lower temperatures tend to have lower sugar concentrations and higher acidity, affecting their taste quality. Hormonal regulation is another critical aspect of sugar and organic acid metabolism in pitaya. Hormones such as ethylene, auxins, and abscisic acid are known to influence fruit ripening and the associated metabolic pathways (Durán-Soria et al., 2020). These hormones interact with sugar signaling mechanisms to modulate the expression of genes involved in sugar and acid metabolism, thereby affecting the overall flavor and nutritional quality of the fruit (Li et al., 2018; Durán-Soria et al., 2020). For instance, methyl jasmonate (MeJA) treatment has been shown to enhance sugar metabolism and phenolic accumulation in pitaya, contributing to improved flavor and quality. 5 Factors Influencing Sugar and Organic Acid Metabolism 5.1 Genetic factors influencing metabolism Genetic variability plays a crucial role in determining the sugar and organic acid profiles in pitaya. Different pitaya species exhibit distinct sugar and acid compositions, which are influenced by the expression of specific genes. For instance, in yellow-peel pitayas, glucose is the dominant sugar in 'WCHL' pitaya, while sucrose, fructose, and glucose are prevalent in ‘YCHL’ pitaya. Malic and citric acids are the main organic acids in 'WCHL' and 'YCHL' pitayas, respectively (Xie et al., 2022). This genetic diversity underscores the importance of genetic factors in shaping the metabolic profiles of pitaya fruits. Several key genes have been identified that regulate sugar and organic acid metabolism in pitaya. The Dof transcription factors HpDof1.7 and HpDof5.4 are known to enhance the expression of sugar metabolism-related genes such as HpSuSy1 and HpINV2, as well as sugar transporter genes HpTMT2 and HpSWEET14, thereby facilitating sugar accumulation (Mou et al., 2022). Additionally, the WRKY transcription factor HpWRKY3 has been shown to activate the expression of HpINV2 and HpSuSy1, further contributing to sugar accumulation during fruit maturation (Wei et al., 2019). The SWEET family genes, particularly HuSWEET12a and HuSWEET13d, also play significant roles in sugar accumulation in pitaya fruits (Figure 2) (Jiang et al., 2023). 5.2 Environmental conditions and cultivation practices Environmental conditions such as temperature, light, and soil quality significantly influence the metabolism of sugars and organic acids in pitaya. Optimal temperature and light conditions are essential for the proper functioning of metabolic pathways that govern sugar and acid synthesis. Soil conditions, including nutrient availability and pH, also affect the metabolic processes. For example, the accumulation of betalains, which are associated with sugar and organic acid metabolism, is influenced by these environmental factors (Wu et al., 2019). Irrigation and fertilization practices are critical in maintaining the balance between sugars and organic acids in pitaya fruits. Adequate irrigation ensures the proper hydration of the plant, which is necessary for the efficient transport and metabolism of sugars and acids. Fertilization provides essential nutrients that support the metabolic pathways involved in sugar and acid synthesis (Diógenes et al., 2022; Oliveira et al., 2022). The balance between these practices can significantly impact the flavor and nutritional quality of the fruit.
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