Insufficient forage is a significant factor limiting the development of animal husbandry in high-altitude pastoral areas. This study aims to identify suitable high-quality forage Triticale (x Triticosecale Wittmack) varieties for cultivation in the Qaidam Basin and determine their optimal harvest period. Seven triticale varieties were selected as experimental materials, and their production performance and nutritional quality were comprehensively analyzed at four different growth stages [booting stage (BTS), heading stage (HDS), flowering stage (FLS), and milk stage (MKS)] in 2024 and 2025, utilizing Pearson correlation analysis, PCA, and TOPSIS methods. The results indicated that as the reproductive period progressed, plant height, dry matter yield, and dry matter content exhibited a continuous increase. In contrast, indicators such as stem diameter, number of green leaves, and fresh biomass yield initially increased before subsequently declining. The MKS soluble sugar content (SS) and relative feed value (RFV) were the highest, crude protein (CP) and crude ash content (CA) decreased, the neutral detergent fiber content (NDF) and the acid detergent fiber (ADF) content reached their peak in the HDS. The relative forage quality (RFQ) reached its peak during the flowering period. Comprehensive analysis showed that the top five rankings are QSM-8 > JSM-3 > QSM-1 > JSM-2 > QSM-7. In the Qaidam Basin, the optimal harvest period from the FLS to the MKS ensures both high yield and good nutritional quality, making it suitable for promotion in the Qaidam Basin region and similar ecological zones.

Saline–alkali land is widely distributed worldwide, and poses significant challenges to agricultural productivity and ecological restoration, particularly in the Qaidam Basin. This study investigates the effects of intercropping and mixed sowing systems of oats (Avena sativa L.) and forage peas (Pisum sativum L.) on hay yield and soil chemical fertility in mildly saline–alkali soils of the Qaidam Basin. Through a comprehensive analysis of hay yield, soil chemical properties, and enzyme activities under different sowing methods (mixed sowing, intercropping, and monoculture) and row spacings (30, 25, 20 and 15 cm), an optimal planting pattern was identified. The 25 cm intercropping treatment produced the highest amount of fresh biomass (2242 kg hm⁻¹), with an increase ranging from 3.17% to 70.44% compared to other treatments. Additionally, this treatment led to significant reductions in soil pH and electrical conductivity (by 3.87–8.31% and 5.13–6.05%, respectively), while enhancing organic matter content and enzyme activities. The intercropping system also demonstrated higher ammonium nitrogen and available phosphorus contents compared to the mixed sowing system. Structural equation modeling revealed that row spacing indirectly influenced both hay yield and enzyme activities, with the 25 cm row spacing proving to be the most effective. A comprehensive evaluation using the TOPSIS model further affirmed that the 25 cm intercropping system significantly enhanced hay yield, soil chemical properties, and enzyme activities, making it the most suitable planting pattern for sustainable land management in the study area. Therefore, the 25 cm intercropping model not only optimizes hay yield, but also improves soil quality and ecological functions in saline–alkali land, offering valuable insights and practical recommendations for the sustainable use of saline–alkali land in the Qaidam Basin.

Interactions between species give rise to chemical pathways of communication that regulate the interactions of transboundary species. The communication between nematodes and other species primarily occurs through the regulation of chemicals, with key species including plants, insects, bacteria, and nematode-trapping fungi that are closely associated with nematodes. G protein-coupled receptors (GPCRs) play a crucial role in interspecies communication. Certain flp genes, which function as GPCRs, exert varying degrees of influence on how nematodes interact with other species. These receptors facilitate the transmission of corresponding signals, thereby completing the interactions between species. This paper introduces the interactions between nematodes and other species and discusses the role of GPCRs in these organisms, contributing to a deeper understanding of the impact and significance of GPCRs in cross-border regulation between nematodes and other species. Furthermore, it is essential to leverage GPCRs in efforts to control pests.

White-flowered alfalfa (Medicago sativa L.) persisting in Qinghai–Tibet Plateau’s saline–alkali habitats provides a unique model to explore floral color polymorphism-linked ecological adaptation. We systematically compared phenotypic, physiological, transcriptomic, and metabolomic profiles of white-flowered (WF) and purple-flowered (PF) alfalfa under high-altitude cold/saline–alkali field conditions (three biological replicates; Student’s t-test). WF showed a significant growth-defense trade-off: flower size and chlorophyll a content decreased by 18.9% and 46.0%, with reduced gibberellin levels, while jasmonic acid (36.3%), proline (51.5%), antioxidant enzyme activities, total flavonoids (17.7%), and condensed tannins (18.2%) were significantly increased (p < 0.001). Multi-omics analysis revealed phenylpropanoid pathway reprogramming (suppressed anthocyanin biosynthesis, precursor accumulation) and coordinated hormone signaling (jasmonic acid activation, salicylic acid inhibition). Our findings confirm the white-flower trait is not an isolated mutation. It is a key component of a coordinated adaptive syndrome, mediated by metabolic reprogramming and hormonal crosstalk. These results provide theoretical and technical support for breeding stress-resistant alfalfa varieties suitable for marginal land cultivation.

This study addresses the challenge of establishing alfalfa (Medicago sativa L.) in the desertified saline–alkali region of the Qaidam Basin, where seedling survival and productivity are considerably constrained. A two-year field experiment was conducted to identify suitable companion crops by comparing an alfalfa monoculture (control) with alfalfa intercropped with oat (Avena sativa L.) (O+A), forage pea (Pisum sativum L.) (P+A), or triticale (xTriticale Wittmack) (T+A). Agronomic traits, yield, and nutritional quality were measured, and a comprehensive evaluation was performed using the TOPSIS (Technique for Order Preference by Similarity to Ideal Solution) model. The results indicated that intercropping with oat produced the highest fresh and dry matter yields in the establishment year, while triticale and pea treatments exhibited strong yield potential in the subsequent year. Triticale significantly enhanced alfalfa’s nutritional quality by increasing crude protein content and relative feed value (RFV) while reducing fiber content. The TOPSIS model ranked the oat treatment highest for overall performance, effectively balancing yield and quality. In conclusion, oats are recommended as a companion crop to enhance alfalfa establishment in this saline–alkali environment, whereas triticale offers distinct advantages for improving the nutritional value of the forage.

The optimization of mowing management is crucial for establishing a high-yielding “one sowing, two harvests” system for oat (Avena sativa L.) forage production in the alpine regions of the Tibetan Plateau. This study aimed to identify the optimal combination of cutting stage and stubble height to maximize the total seasonal productivity of the system. A two-factor field experiment, arranged in a randomized complete block design, was conducted over two consecutive growing seasons (2024 and 2025) using the local cultivar ‘Qingtian No. 1’. The treatments consisted of two cutting stages (flowering stage, C₁; milk stage, C₂) and three stubble heights (5 cm, H₁; 10 cm, H₂; 15 cm, H₃). Regarding regrowth phase performance, mowing at the flowering stage (C₁) resulted in significantly superior agronomic traits (e.g., stem diameter, tiller number) and photosynthetic characteristics compared to the milk stage (C₂). In terms of forage quality, the C₂H₂ treatment maximized water-soluble carbohydrate content but also led to elevated fiber levels. However, the key metric for system evaluation—the total seasonal dry matter yield—was predominantly governed by the cutting stage. Mowing at the milk stage (C₂) consistently resulted in a higher total yield than C₁, with optimal combinations yielding 1.31 t/ha (C₂H₁) in 2024 and 1.25 t/ha (C₂H₂) in 2025. This advantage was primarily due to a substantially greater first-harvest yield under C₂, which outweighed the regrowth benefits of C₁. A comprehensive evaluation based on total system productivity and forage quality indicates that mowing at the milk stage (C₂) is the optimal strategy for achieving high total output. For ‘Qingtian No. 1’ oat in this region, a stubble height of 10 cm (as in the C₂H₂ treatment) is recommended to ensure robustness across years. This management strategy secures a high total seasonal forage yield through effective biomass allocation between harvests, extending the supply window and offering a sustainable cultivation model for this ecologically vulnerable region.