The Northeast Farming-pastoral ecotone (NFPE) in China is crucial for farming and pastoralism. However, sustainable development of land resources faces several challenges from human activities and environmental degradation. Thus, assessing land resource-carrying capacity (LRCC) is crucial for effective land-use planning and management. This study proposes a comprehensive indicator system to evaluate LRCC in the NFPE. We integrate remote sensing, model simulation, and statistical data, employing Geographic Information System analysis and statistical techniques to assess spatiotemporal evolution characteristics of LRCC. Findings indicate increasing LRCC with spatial-temporal heterogeneity. The northern region exhibits relatively high and growing LRCC, while some eastern regions have low LRCC but a high growth trend. The southern region displays both low LRCC and growth. Balancing regional development and ecological protection requires considering spatial heterogeneity of LRCC in land-use planning and management decisions, facilitating differentiated land-use strategies for sustainable development.

The implementation of ecological restoration programs is intensively changing the original ecological carrying capacity and the status of ecological security. To evaluate the spatiotemporal variation of ecological carrying capacity and ecological security in China’s eco-engineering areas, an indicator system of ecological carrying capacity and ecological security should be developed. This study developed an evaluation indicator system that contains 29 indicators. The indicators were generated by long-time series and multi-source data. The indicator system presents the relationship between ecological carrying capacity and ecological security and reflects the dynamic change of them in eco-engineering areas. We selected the Three-River Headwaters Region (TRHR) and implemented the Ecological Conservation and Construction Program (ECCP) as a case study. The results showed the variation of ecological carrying capacity (ECC) and ecological security (ES) in the TRHR before (2000–2004), during early term (2005–2009), and during medium term (2010–2015) implementation of ECCP, and limiting factors of ecological carrying capacity and ecological security in TRHR was analyzed. The results showed that the ECC index and the ES index were significantly increase, indicating that the ECC improved and that the ES state got better in the TRHR after implementing ECCP. The water conservation was the major factors limiting the increase of the ECC. The leading factors limiting the improvement of the ES were educational expenditure before 2010 and turned into proportion of tertiary industry and investments for ecological restoration after 2010. The implementation of the ECCP has improved the ES state but has also resulted in new problems. It provides a scientific reference for future research on the indicator system of ecological carrying capacity and ecological security in eco-engineering areas and also has vital practical significance to guide the sustainable development of ecological restoration programs.

Solanum lycopersicumvar.cerasiformeaccession PI 114490 has broad-spectrum resistance to bacterial spot caused by several species ofXanthomonas. Resistance is quantitatively inherited, and a common quantitative trait locusQTL-11Bon chromosome 11 has been identified previously. In this study, theSlPub24gene was characterized inQTL-11B.SlPub24in PI 114490 was upregulated by infection withX.euvesicatoriapv.perforansrace T3, but its transcription was low in the susceptible line OH 88119 whether or not it was infected by the pathogen. The differential expression ofSlPub24between PI 114490 and OH 88119 was due to great sequence variation in the promoter region. The promoter ofSlPub24in OH 88119 had very low activity and did not respond to pathogen infection. Transgenic lines of OH 88119 overexpressingSlPub24isolated from PI 114490 showed significantly enhanced resistance, while mutants ofSlpub24generated by CRISPR/Cas9 editing showed more susceptibility to race T3 and to other races. The mutants also showed spontaneous cell death in leaves. The expression of the salicylic acid (SA) pathway gene phenylalanine ammonia-lyase (PAL) and signaling-related genes pathogenesis-related (PR1)and nonexpresser ofPR1 (NPR1) were influenced bySlPub24. The content of SA in tomato plants was consistent with the level ofSlPub24expression. Furthermore, SlPUB24 interacted with the cell wall protein SlCWP and could regulate the degradation of SlCWP. The expression levels ofSlCWPandSlCWINV1, a cell wall invertase gene, showed opposite patterns during pathogen infection. The activity of SlCWINV1 was lower in mutants than in PI 114490. The results are discussed in terms of the roles of the abovementioned genes, and a potential model for SlPUB24-mediated resistance to bacterial spot is proposed.

As an important means of production and habitation, land is the core natural resource for people’s life and production. However, the escalating demand for land resources, along with population growth, has created a pressing challenge at the intersection of land, population, and grain. In this study, we used a combination of temporal and spatial perspectives, along with spatial analysis methods, to analyze the supply and demand of land resources in the Northeast Farming–Pastoral Ecotone (NFPE) based on the population–grain relationship. The results show that the carrying capacity of land resources in this region increased gradually and the number of people it can carry increased from 34.23 million (2000) to 127.96 million (2018). From 2000 to 2018, the land resource carrying index (LRCI) was greater than 1.125, showing a state of surplus in grain, and the LRCI increased by 0.23 per year. Most areas in this region are in a state of grain surplus, with 13 counties showing a population and grain balance, and 2 counties being overpopulated. However, the increasing trend of land resource carrying capacity of the overpopulated areas and the balanced population–grain areas are notable. The carrying capacity of land resources in the NFPE generally exhibits a positive trend with a surplus of grain; however, there are spatial variations. Areas in the south and northeast demonstrate lower change trends, while the north and southeast exhibit higher change trends. This research provides critical insights into the dynamic interplay between land, population, and grain, enabling informed decision making for sustainable development in the NFPE and offering valuable lessons for similar regions globally.