Abstract:Potato ranks as the worlds fourth-largest staple crop exhibiting high yield potential. Selection of early-maturing， high-yielding potato varieties with stable disease resistance is an urgent need to meet future food security challenges. In this study， to support new cultivar development and elucidate current potato breeding trends in China， 227 potato breeding literatures from the China National Knowledge Infrastructure （CNKI） database were used. We deployed GraphRAG and Qwen2-70B-instruct to construct a knowledge graph， which was subsequently visualized by using Gephi. Based on the constructed knowledge graph， we analyzed the genealogy， resistance and fertility period of new potato varieties selected and bred in China from 2004 to 2024. Our findings revealed that prominent parental lines in breeding programs included Ji Zhang Yam 8， Svante， Feiuretta， and Early Large White， etc. Most potato cultivars were resistant to late blight， with the majority classified as mid-late to late maturity types. In summary， this study explored the realization path of using a large language model to rapidly construct a knowledge graph for potato new variety selection and breeding research， providing a reference for the future discovery and utilization of potato germplasm resources.

Abstract:Potato cyst nematode （PCN） is an important quarantine disease and its infection can reduce the potato yield up to 80%. In recent years， the potato golden nematode （Globodera rostochiensis） was reported in several major producing areas in Southwest of China. In order to ensure the safety of potato production in China， it is urgent to identify germplasm resources with cyst resistance and breed for resistant varieties. Using the molecular markers N146， N195， 57R， TG689， Gro1-4-1 and Gpa2-2 from earlier studies， in this study 875 potato germplasm accessions preserved by Yunnan Academy of Agricultural Sciences were genotyped for resistance genes to potato cyst nematode. 211 accessions were detected with H1 molecular markers （N146，? N195， 57R and TG689） amplifying the resistance gene to potato cyst nematodes， of which 114 accessions contained four molecular markers at the same time. Seven accessions were identified carrying the resistance gene Gro1-4， while 237 resources were found with Gpa2-2 resistance gene Gpa2. Collectively， this study provided technical support and material basis for the breeding of potato cyst nematode resistance.

Abstract:Based on the third national census of crop germplasm resources and collecting action, 246 sweet potato germplasm resources were collected from 14 regions in Hunan Province, and a set of rapid and effective nested PCR detection method for sweet potato leaf curl virus (SPLCV) was established to investigate the situation of infection and distribution of SPLCV in Hunan province through the rate of virus infection. The results showed that the infection rate of SPLCV was 8.1% in Hunan, and there are fourteen sweet potato resources contained sweet potato leaf curl virus in the four regions of Shaoyang, Changsha, Yongzhou and Zhuzhou, and the infection rate of SPLCV was17.6%, 14.5%, 7.1% and 6.7% respectively, which had great regional differences. This study was the first time to detect and investigate SPLCV in Hunan province, which provided data reference for the situation of infection and distribution of SPLCV in Hunan province. It also provided important technical support for the preservation, reproduction and subsequent development and utilization of sweet potato resources.