Sweet potato is one of the most economically important crops for addressing global food security and climate change issues, especially under conditions of extensive agriculture, such as those found in developing countries. However, osmotic stress negatively impacts the agronomic and economic productivity of sweet potato cultivation by inducing several morphological, physiological, and biochemical changes. Plants employ many signaling pathways to respond to water stress by modifying their growth patterns, activating antioxidants, accumulating suitable solutes and chaperones, and making stress proteins. These physiological, metabolic, and genetic modifications can be employed as the best indicators for choosing drought-tolerant genotypes. The main objective of sweet potato breeding in many regions of the world, especially those affected by drought, is to obtain varieties that combine drought tolerance with high yields. In this regard, the study of the physiological and biochemical features of certain varieties is important for the implementation of drought resistance measures. Adapted genotypes can be selected and improved for particular growing conditions by using suitable tools and drought tolerance-related selection criteria. By regulating genetics in this way, the creation of drought-resistant varieties may become cost-effective for smallholder farmers. This review focuses on the drought tolerance mechanisms of sweet potato, the effects of drought stress on its productivity, its crop management strategies for drought mitigation, traditional and molecular sweet potato breeding methods for drought tolerance, and the use of biotechnological methods to increase the tolerance of sweet potato to drought.

Potatoes (Solanum tuberosum L.) constitute one of the most economically important annual crops. In terms of tissue culture, potato microtubers (MTs) have a number of advantages over conventional plants. These advantages include their small size, which greatly facilitates storage, transport, and germplasm exchange compared to in vitro plants. One effective solution for the production and mass propagation of healthy MTs is the use of temporary immersion systems (TISs). In this study, in a SETIS^TM system containing kinetin/gibberellic acid (GA)/indole-3-butyric acid (IBA) hormones, we investigated the effects of different nutrient media on the morphological characteristics of potato explants and MTs. We determined the optimal cycling duration (3 h) with an immersion frequency of 2 min. The results revealed that the optimal nutrient medium for culturing single-node potato explants in a SETIS^TM bioreactor was the M7 medium containing kinetin (2 mg/L), GA (0.5 mg/L), and IBA (0.5 mg/L). The optimal nutrient medium for obtaining potato MTs was the M1 medium (hormone-free) with a high concentration of sucrose (9%) at 18 °C under dark growing conditions. Thus, a universal nutrient medium, employed in a bioreactor, was selected for the mass propagation of potato MTs for both domestic and foreign potato varieties.

Research Highlights: Despite a long tradition of using poplars as wood source across Central Asia, recent international breeding developments have not penetrated that region yet. This study therefore explored growth performance of 30 local and international poplar cultivars. Background and Objectives: The Central Asian countries are forest poor countries, which need to cover the domestic wood demand through costly imports. Therefore, fast growing trees, such as poplars, are gaining increasing attention as option to grow wood domestically. The most common cultivars date back to Soviet Union times. As recent breeding developments have not reached the region, this study aims at investigate the growth performance of a number of newly developed poplar cultivars. Materials and Methods: The investigated cultivars were planted as cuttings across nine sites in Kyrgyzstan, Kazakhstan, and Tajikistan between 2018 and 2020. Results: Under warm climate conditions, i.e., low elevations, P. deltoides x nigra hybrids attained highest stem volumes and biomass yields, up to 16.9 t/ha*a after two years, followed by P. nigra xmaximoviczii hybrids. One of the P. deltoides xnigra hybrids reached a tree height of 10.5 m after three years. On higher elevations, e.g., in the Pamirs and in Naryn, P. maximoviczi x trichocarpa hybrids and P. trichocarpa cultivars grew faster than the former hybrids. Conclusions: The cultivars explored in this study should be included into plantations or agroforestry systems that are being established, provided that land users are able to thoroughly control weeds and ensure nutrient and water supply. If sufficient weed control, nutrient supply, or water supply cannot be ensured, then land users should opt for local cultivars (e.g., Mirza Terek) or the P. nigra xmaximoviczii hybrids or P. trichocarpa, in order to avoid failure.

Potato is the third most important food crop in the world in terms of adaptability, yield potential, and nutritional advantages. This study aimed to conduct potato breeding work for cultivation in Kazakhstan; potato breeding for further processing into chips with cultivation in the northern regions; and the selection of potatoes for processing into frozen French fries with cultivation in the southern and south-eastern regions. Potato varieties (Fontane, Santana, and Punchy) were used as reference varieties to check molecular markers linked to maturity, tuber shape, and flesh color. A total of 42 potato breeding lines crossed from Yagodnyi 19 and CIP clone 397079-6 were used in this study to identify prospective breeding lines. The research was carried out between 2023 and 2024 and under greenhouse conditions. According to the results of molecular analysis and phenotypic data, 21 breeding lines were identified as prospective potato breeding lines. The majority of these potato breeding lines had a round tuber shape and were recommended for chip processing. Three breeding lines had a long oval tuber shape, making them suitable for French fries. Six breeding lines with short-oval and oval tuber shapes were found for consumer potato processing. It is recommended that the breeding process and studies of biochemical properties are continued in all of these identified potato breeding lines.

Drought has increasingly affected the yield of Solanum tuberosum L. (potato) every year over the last decade, posing serious economic problems for the global agricultural industry. Therefore, it is important to research drought tolerance in plants and obtain more robust varieties of crops. The aim of the present work was to study the expression of drought-upregulated genes in drought-tolerant and drought-sensitive varieties of potato. Bioreactors were used to identify whether each variety was drought-tolerant or drought-sensitive; then, expression analysis was performed according to the morphological characteristics of the plantlets in two different media: Murashige and Skoog (MS) medium and MS medium with 20% PEG-6000 to simulate osmotic stress. Based on the quantitative parameters of six initial varieties, two varieties were selected (Gala and Aksor) for further gene expression analysis. The expression of genes commonly upregulated in drought (ER24, TAS14, DREB147315, PP2C, 102605413 and NF-YC4) was higher in the drought-tolerant variety than in the sensitive one. Therefore, the expression of these genes can be used to determine the drought tolerance of a potato variety in vitro in the early plant development stage. Moreover, comparative analysis showed that some of the targeted genes used to identify drought tolerance in this study are conserved across different plant species.