VARIETY TESTING AND ADAPTATION OF INTRODUCED (NON-LOCAL) WHEAT VARIETIES ON SALINE SOILS OF KARAKALPAKSTAN

SCIENCE AND INNOVATION INTERNATIONAL SCIENTIFIC JOURNAL VOLUME 4 ISSUE 12 DECEMBER 2025 ISSN: 2181-3337 | SCIENTISTS.UZ 114 VARIETY TESTING AND ADAPTATION OF INTRODUCED (NON-LOCAL) WHEAT VARIETIES ON SALINE SOILS OF KARAKALPAKSTAN Z.E. Polatova¹, N.P. Mirametova², E.P. Sadikov³ Master’s student (2nd year)1 Doctor of Biological Sciences (PhD), Associate Professor2 Candidate of Agricultural Sciences, Senior Researcher3 Ajiniyaz Nukus State Pedagogical Institute, Republic of Karakalpakstan, Department of Biology, 230100, Nukus city, P. Seitov Street, building without number1,2 Scientific and Production Association of Grain and Rice, Republic of Karakalpakstan, 230910, Nukus district, Shortanbay settlement3 https://doi.org/10.5281/zenodo.17982453 Abstract. The article is devoted to the problem of variety testing and adaptation of introduced (non-local) wheat varieties on saline soils of the Republic of Karakalpakstan, a region characterized by a high degree of soil salinization caused by the environmental consequences of the Aral Sea desiccation and intensive irrigation. The study examines the characteristics of saline soils, methods of laboratory and field testing, as well as the results of evaluating more than 200 introduced genotypes of winter and spring wheat from collections of CIMMYT, Russia, Kazakhstan, and other countries. Promising salt-tolerant varieties (Utiqul-96, GAN-91, Kerim, Oqmarvarid, Paxlavon, etc.) demonstrating stable productivity and grain quality under salt stress conditions are identified. The impact of salinization on morphological, phenological, and technological traits of plants is discussed, along with opportunities to enhance adaptation through the use of biostimulants. The author emphasizes the necessity of utilizing introduced donor varieties in breeding programs to develop new resistant cultivars, thereby contributing to improved food security in the region. Keywords: saline soils, Karakalpakstan, variety testing, introduced (non-local) varieties, winter wheat, spring wheat, salt tolerance, adaptation, yield, grain quality, CIMMYT, salt stress, biostimulants, wheat breeding. Introduction. The Republic of Karakalpakstan, located in the northwestern part of Uzbekistan, is a region characterized by extreme natural and climatic conditions. The area is dominated by an arid climate, high soil salinity, and a shortage of water resources, all of which are exacerbated by the ecological catastrophe of the Aral Sea desiccation. Soil salinization is one of the key challenges facing agriculture in the region, affecting more than 50% of arable land. This results in a decline in crop productivity, particularly in cereal crops such as wheat, which is the main staple food crop in Uzbekistan. Wheat provides up to 60% of the population’s caloric intake and plays a significant role in the national economy. Under saline conditions, traditional local wheat varieties often exhibit insufficient tolerance, leading to yield losses of up to 30–50%. To address this problem, variety testing and adaptation of introduced (non-local) wheat varieties—introduced from other regions or countries—are conducted. Introduced varieties, including those obtained from global collections of CIMMYT (the International Maize and Wheat Improvement Center), offer valuable genetic SCIENCE AND INNOVATION INTERNATIONAL SCIENTIFIC JOURNAL VOLUME 4 ISSUE 12 DECEMBER 2025 ISSN: 2181-3337 | SCIENTISTS.UZ 115 potential for enhancing tolerance to salinity, drought, and low temperatures. The aim of such studies is to identify varieties capable of adapting to salt stress while maintaining high yield and grain quality. This article examines testing methods, adaptation results, and prospects for the use of introduced wheat varieties in Karakalpakstan. Characteristics of Saline Soils in Karakalpakstan. Soil salinization in Karakalpakstan is caused by several factors, including the evaporation of the Aral Sea, irrigation using mineralized water from the Amu Darya River, and secondary salinization resulting from inefficient drainage systems. According to research data, the chloride ion content in the upper soil layer (0–30 cm) ranges from 0.043% to 0.089%, while sulfate ion content varies from 0.012% to 0.192%. These levels are classified as moderate to high salinity, which suppresses plant growth due to osmotic stress, ion toxicity, and nutrient imbalance [1]. The region is dominated by meadow-alluvial and sierozem soils with a pH of 7.0–8.0, groundwater depth of 2.0–2.5 m, and mineralization levels of 1.5–2.5 g/L. Soil salinization shortens the wheat growing season by 4–6 days, reduces plant height by 6–8 cm, and decreases yield by 20–40%. Local varieties, such as Karakalpakistan-100, demonstrate relatively better adaptation; however, to improve productivity, introduced genotypes with higher tolerance are required. Studies emphasize that salinity affects all developmental stages of wheat—from germination to maturity—causing a delay in seedling emergence by 2–3 days and a reduction in plant stand density [2]. Methods of Variety Testing. Variety testing was conducted under both laboratory and field conditions to ensure a comprehensive assessment of adaptation. Laboratory methods included seed germination in NaCl solutions (0.5–2.0%) at a temperature of 24–26 °C. Germination percentage, seedling length, number of roots, and overall seedling development were evaluated. For example, at a concentration of 2% NaCl, local wheat varieties achieved a germination rate of up to 97%, whereas many introduced (non-local) varieties produced abnormal or rootless seedlings. Field trials were carried out on both saline and non-saline plots, including sites at the Scientific and Production Association of Grain and Rice of the Republic of Karakalpakstan, located in the Nukus district, Shortanbay settlement. Standard agronomic practices were applied, including sowing after a preceding crop (e.g., rice), recommended fertilizer rates, and irrigation regimes. Phenological observations covered growth stages, overwintering performance, plant survival, spike length, number of grains per spike, thousand-kernel weight, yield, grain vitreousness, protein and gluten content, as well as the quality index (IDK). Under saline soil conditions, the wheat growing season was shortened by 7–12 days, which was taken into account in breeding and selection programs [3]. The studies involved testing more than 150–200 samples from global germplasm collections, including varieties from Russia, Kazakhstan, Turkey, and Mexico. To enhance adaptive capacity, biostimulants such as Chlorella vulgaris were applied; their use reduced soil salinity by 0.9–1.2 g/L, accelerated crop maturity by 5–7 days, and increased yield by 12.2%. Introduced Wheat Varieties and Their Testing. Introduced (non-local) wheat varieties are incorporated to enrich the genetic pool. From global CIMMYT collections, more than 320 accessions of soft winter wheat were tested. The key introduced varieties include:  Avoset-s, Kerim, GAN-91, Utiqul-96, 040609, 040812: identified as salt-tolerant donor varieties with high productivity [2]. SCIENCE AND INNOVATION INTERNATIONAL SCIENTIFIC JOURNAL VOLUME 4 ISSUE 12 DECEMBER 2025 ISSN: 2181-3337 | SCIENTISTS.UZ 116  Tanya, Bezostaya-1, Polovchanka, Krasnodar-99, Utkir, Akmangit: originating from Russia and Kazakhstan and tested under saline field conditions [1].  Anza, Cham-1, Arrebane, Cook, Pavon-76: sourced from international collections and characterized by rapid root system development.  Khumo, Taraqqiyot, Emir, Pervitsa, Rhapsody, Zimnitsa, Drujba: tolerant to high salinity levels (1.5% NaCl), with germination rates ranging from 70% to 100%. For spring wheat, the varieties Oqmarvarid, Paxlavon, Ezoz, Qayroqtosh, and Ilgor, introduced from neighboring regions, were evaluated and exhibited a growing period of 81–83 days [5]. Testing focused on winter hardiness, salinity and drought tolerance, and yield performance. For example, the varieties ASR and Antonina were assessed according to these traits, demonstrating variability in adaptation to multiple stress factors. Results of Adaptation of Introduced Varieties. The adaptation of introduced wheat varieties showed mixed results. Under saline soil conditions, yield components declined: the number of grains per spike decreased by 5–10%, thousand-kernel weight by 2–6 g, and grain vitreousness by 5–6%. However, salt-tolerant varieties such as Utiqul-96, GAN-91, 040609, and Kerim maintained stable productivity, with minimal differences between saline and non-saline environments. These varieties are characterized by good tillering capacity, large grain size, and resistance to lodging [1]. In laboratory tests, the varieties Khumo, Taraqqiyot, and Emir demonstrated high tolerance, showing normal development even at 1.5% NaCl. Field data confirmed that although the growing season is shortened on saline plots, post-winter survival rates are higher in tolerant genotypes (6.9–26.2%). For spring wheat, Oqmarvarid and Paxlavon achieved yields of 25–30 c/ha, with gluten content of 28–30% and IDK values of 76–94, classifying their grain quality as “good” [5]. Hormonal changes under salt stress were also observed: levels of cytokinins, indole-3butyric acid (IBA), and abscisic acid (ABA) varied, influencing plant growth. While salinity suppresses growth, tolerant varieties adapt through enhanced root system development and osmotic regulation. Local varieties, such as Karakalpakistan-100, generally exhibit higher tolerance than introduced ones; however, hybridization with introduced donor varieties significantly increases adaptive potential [2]. Table 1. Comparison of Productivity of Selected Wheat Varieties on Saline and Non-Saline Soils (Averaged Data) Variety Growing period (days, saline / non-saline) Thousand-kernel weight (g, saline / non-saline) Yield (c/ha ) Utiqul-96 245/251 38/40 2530 GAN-91 243/249 37/39 2428 Kerim 242/248 36/38 2327 Oqmarvarid (spring wheat) 81 - 25 SCIENCE AND INNOVATION INTERNATIONAL SCIENTIFIC JOURNAL VOLUME 4 ISSUE 12 DECEMBER 2025 ISSN: 2181-3337 | SCIENTISTS.UZ 117 Paxlavon (spring wheat) 81 - 25 Biostimulants such as Chlorella enhance plant adaptation by increasing survival rate by 1.4%, plant height by 9.2%, and yield by 12.2%. Recommendations and Prospects. It is recommended to utilize salt-tolerant donor varieties (Utiqul-96, GAN-91, Kerim) in breeding programs aimed at developing new wheat cultivars. The implementation of biostimulants and improved irrigation practices can further enhance the adaptation of introduced (non-local) wheat varieties. Future prospects include the application of genetic engineering approaches to strengthen osmotic regulation and root system development. Additional trials in different micro-regions of Karakalpakstan are required to optimize adaptation strategies [6]. Conclusion. Variety testing and adaptation of introduced (non-local) wheat varieties on saline soils of Karakalpakstan are key factors for achieving sustainable agriculture. Although local varieties demonstrate superior tolerance, introduced varieties provide valuable genetic resources for improving stress tolerance and productivity. The integration of laboratory and field methods enables the identification of promising genotypes, thereby contributing to regional food security. Further research will strengthen Uzbekistan’s position in the breeding of salt-tolerant crops. REFERENCES 1. Султанова З.С., Пурханова А. Технологические показатели качества зерна сортов озимой пшеницы в почвенно-климатических условиях южного Приаралья // Research Gate. - 2023. - URL: https://www.researchgate.net/publication/367167168 2. ICARDA Research Report. Performance of winter and spring wheat genotypes on medium saline soils in Chimbay, Karakalpakstan, Uzbekistan // MEL CGIAR. -2015. -URL: https://mel.cgiar.org/reporting/download/hash/2850N5JJ 3. Begdullayeva T., Kienzler K.M., Kan E. et al. Response of Sorghum bicolor varieties to soil salinity for feed and food production in Karakalpakstan, Uzbekistan // Irrigation and Drainage Systems. -2007. -Vol. 21. -P. 237-250. 4. О подборе сортов озимой пшеницы // Министерство сельского хозяйства Республики Узбекистан. -URL: https://agro.uz/ru/services/recommendations/4537/ 5. Galaxy International Interdisciplinary Research Journal. Productivity of spring wheat cultivars in saline soils of Karakalpakstan // GIIRJ. -2023. -URL: https://internationaljournals.co.in/index.php/giirj/article/download/5383/5062/5399 6. Аминов С., Туктакузиев А., Нурабаев Ж. Технология подготовки почвы и технические средства совмещения посевов при возделывании сельскохозяйственных культур в условиях Каракалпакстана // Universum: технические науки. -2022.- № 3(96). – URL: https://7universum.com/ru/tech/archive/item/ 13317