Sodium nitroprusside (SNP), as a nitric oxide donor, is widely used in postharvest fruit physiology and metabolism. Our previous study has indicated that SNP plays a crucial role in postharvest browning control of rambutan, but the molecular mechanism underlying this process is still unclear. In this research, we investigated the gene expression and function of postharvest rambutan in response to SNP during browning. We found 7336 differentially expressed genes (DEGs), among which 2206 were upregulated and 5130 were downregulated. Gene Ontology (GO) enrichment as well as Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were performed, and the real-time quantitative PCR (qPCR) data were consistent with transcriptome data. The DEGs relevant to rambutan pericarp browning were mainly involved in anthocyanin biosynthesis, phenolic oxidation, reactive oxygen species (ROS) production, and energy supply. It was shown that SNP regulated the synthesis and degradation of anthocyanins, accumulation of phenols, level of ROS and energy metabolism to suppress the postharvest browning of rambutan. Also, one WRKY transcription factor involved in ROS metabolism was observed to be differentially regulated. These findings add to our insights into the molecular mechanisms of the SNP-induced browning delays of rambutan, which has implications for subsequent studies on molecular mechanisms of fruit browning.

Surface browning after harvest is the primary constraint affecting the storage life and market circulation of rambutans. In this study, rambutan fruits were soaked in sodium nitroprusside at different concentrations and stored at 25°C for 8 days to explore the effects on postharvest quality and browning. The weight loss, browning index and superoxide anion radical, hydrogen peroxide and malondialdehyde contents of the treated fruits were reduced compared to those of the control fruits (soaked in distilled water). And fruits treated with sodium nitroprusside had a higher total phenolic content and lower polyphenol oxidase and peroxidase activity. In addition, compared with the control, the treated fruits exhibited higher phenylalanine ammonia lyase, ascorbate peroxidase and superoxide dismutase activities; titratable acidity; and soluble solid, vitamin C and protein contents, indicating high fruit quality. Overall, sodium nitroprusside treatment at 200 μmol L−1 demonstrated the most positive preservation effects. Therefore, sodium nitroprusside treatment, particularly at 200 μmol L−1, can be used as an eco-friendly, safe and convenient method for postharvest quality management and high-efficiency preservation of rambutan fruits.

Pitaya fruit canker is an important disease in pitaya production. Facilitating resistance through the application of biological control principles is a promising alternative to traditional control strategies. This study evaluated the induced resistance of Penicillium rolfsii, numbered Y17 isolated from papaya leaves in pitaya fruit, and evaluated the activity of the defense enzymes, total antioxidant capacity (T-AOC), and malondialdehyde (MDA) content of the treated fruit. The results demonstrate that treatment with Y17 effectively induced resistance of pitaya fruit to canker disease caused by Neoscytalidium dimidiatum , with an inhibition rate of 70.87%. In addition, Y17 notably improved the activities of peroxidase, catalase, and polyphenol oxidase as well as the T-AOC of the treated samples. Y17 treatment reduced the MDA content in these fruits. Taken together, our results suggest that Y17 treatment could trigger pitaya fruit defense responses and effectively induce resistance to fruit canker disease.

番木瓜是一种重要的热带、亚热带果树资源,其果实属于呼吸跃变型果实,在采后的贮藏运销过程中极易腐烂,影响果品品质,因此番木瓜的采后保鲜在果品的生产流通中起着至关重要的作用.该文归纳了番木瓜果实的物理保鲜技术和化学保鲜技术措施,阐述了具体的保鲜方法、试验研究中保鲜技术的效果以及1-MCP处理技术的分子机理,并对番木瓜的采后保鲜技术及其发展进行了总结与展望,为番木瓜的采后商品化处理以及贮藏运销提供参考.

Coconut (Cocos nucifera L.) is a tropical evergreen crop with high economic value. Low temperature is one of the main environmental factors that limit coconut productivity. Therefore, it is necessary and significant to research the growth trend and physiological changes of coconuts under a low temperature environment. In this study, the physiological response of 20 coconut germplasm resources is presented in an integrated perspective to provide a holistic view of the behavior of coconut trees facing cold stress under four temperature conditions (25 °C, 15 °C, 10 °C, 5 °C). It was shown that low temperature would lead to the increase of relative electrical conductivity, MDA content, soluble protein content, and proline content. In addition, the activities of defense enzymes (SOD, POD, CAT, APX) were increased to resist the cold environment. In a comprehensive analysis, it was revealed that coconut germplasms with high cold resistance, such as C2, C7, and C10 as well as POD activity, proline content, and soluble protein content, were defined as representatives for coconut cold resistance evaluation. Through the exploration of osmotic adjustment substances and defense enzymes, the breeding and quality improvement of cold-resistant coconut varieties could be promoted. As a result, understanding the physiological response and tolerance mechanisms of coconuts to low temperature stress was essential, as this perception may serve as the foundation for coconut resistance evaluation, cultivation, and breeding.

Wax apple is one of the most important commercially grown fruits and is consumed worldwide due to its excellent quality attributes and high degree of acceptance by consumers. However, wax apple is highly perishable and the application of storage and other postharvest technologies is necessary to maintain fruit quality from harvest to consumption. In this study, the effects of sodium nitroprusside (SNP) on the postharvest quality and senescence of wax apple (Syzygium samarangense (Blume) Merr. & Perry) was investigated. The wax apples were treated with three concentrations of SNP (1, 2.5, and 5 mu mol.L-1), and the control was treated with distilled water. The treated fruits were air dried naturally and stored at 25 degrees C (the relative humidity was 90%) for 7 days to determine the various parameters. The results demonstrated that soaking in SNP maintained higher titratable acidity (TA) and soluble solids content (SSC) and sustained a stable Brix-acid ratio (BAR). SNP also suppressed the degradation of anthocyanins and the decrease of firmness. Additionally, it functioned in delayed polyphenol oxidase (PPO) and peroxidase (POD) activities in the early period and suppressed the decrease of the two enzyme activities in the late period. Increases in malondialdehyde (MDA) content were inhibited. In summary, 2.5 mu mol.L-1 SNP significantly maintained the quality and suppressed the senescence of postharvest wax apple fruit compared to the control. Therefore, the application of SNP may represent a promising and practical methodology for extending the shelf life of fruit.

禾生素是一种新型的绿色生物源农药、植物功能性营养剂.经过研究发现,禾生素对农作物、园艺植物的生长发育都会起到一定的促进和辅助作用.对于不同种属的植物使用一定剂量的禾生素或将其与其他功能性营养剂、农药等按一定比例施用都会在一定程度上起到抵御病虫害、抗寒抗旱、缓解药害肥害、增产增质、调节土壤等的效果.基于此,分析禾生素在不同植物中的应用,并对其发展前景进行展望,为禾生素在绿色安全的农产品生产上的推广及应用提供参考.

随着"美丽中国"建设的逐步推进和生态文明体制的改革与发展,高等院校在生态建设过程中的地位越来越重要.近年来,高校植物园的建设与打造也成为农林和医药等学科发展与进步的需求.海南是我国唯一的热带岛屿,拥有独特的热带地域风光和丰富的热带植物资源,作为"211"工程大学和双一流建设高校,海南大学应以特色植物为基础,打造兼具景观性与实用性的植物园,提高科研与教学水平,推动美丽校园工程建设.该文基于植物园建设的发展趋势,分析了海南的自然地理条件与植物资源概况,提出在海南大学海甸校区建设植物园的规划与建议,为海南大学海甸校区的植物景观设计和植物园区打造提供参考.