杨梅叶枯病病原菌鉴定及药剂筛选

杨梅叶枯病是湖南省杨梅的主要病害之一。经鉴定,杨梅叶枯病菌为Phomopsis myricina Y.J.Huang et P.K.Chi。室内20种药剂试验结果表明：抑制该菌的菌丝生长和分生孢子萌发效果较好的杀菌剂是扑菌特、多菌灵、菌克星、退菌特、新万生、代森锰锌、福镁砷、甲基硫菌灵、炭必灵和波尔多液;湘研植病灵和红杀能有效地抑制菌丝生长而不能抑制孢子萌发;相反,疫霜锰锌、大菌丹和石硫合剂能有效地抑制孢子萌发,但不能抑制菌丝生长。其他杀菌剂效果差。     

Effects of forcing cultivation on the leaf morphology,fruit ripening and quality of Myrica rubra北大核心CSCD

【Objective】Chinese bayberry (Myrica rubra) is an unique and valuable fruit crop cultured in southern China. As the most characteristic and prized fruit cultivated in Zhejiang province, it exhibits high levels of both nutritional benefits and economic value, which has significantly improved its market competitiveness. Main cultivated varieties of bayberry, like Dongkui and Biqizhong, mature from early June to early July. However, the bayberry during the maturation period usually encounters the rainy season, which results in severe decline in both yield and quality of bayberry, and further constrains the development of the bayberry industry. Thus, efforts to facilitate more reliable bayberry cultivation have the potential to improve its quality and output. Compared to traditional open-field cultivation, approaches to enhanced cultivation can increase temperatures and reduce the phenological periods for each stage of development, thus mitigating the potential harm caused by the plum rains. In addition, these approaches to protected cultivation can further improve commercial bayberry fruit outputs and promote its economic benefits.【Methods】In order to testify the benefits of protected cultivation for M. rubra, the leaf morphology, fruit ripening and quality of Biqizhong and Dongkui were studied, which were subjected to three different cultivation methods: open field (OF), single- layer- film- covered greenhouse (SLFG), and double-layer-film-covered greenhouse (DLFG). The cultivation of SLFG entailed the construction of a steel frame structure covered by a transparent plastic film based on the shape of the mountain slope, using triangular, arched, or flat roof multi-span steel frames as appropriate. The cultivation of DLFG entailed a novel and efficient cultivation method based on the use of SLFG triangular or arched roof multi-span steel frames on slopes, together with the introduction of a steel frame beam at a distance of 1.0 m from the top, followed by fixing a second transparent plastic film layer. After these protected cultivation models were established, temperature changes, phenological periods, and the relationships between temperature changes and phenological periods were assessed, and the leaf phenotypes and fruit quality were also measured. 【Results】Compared to traditional OF cultivation, the average temperatures under DLFG and SLFG cultivation were 5.1 ℃ and 2.5 ℃ higher, respectively, significantly above the ambient temperatures. The forcing cultivation results in higher daily average temperatures, with a daily average temperature ≥ 10 ℃ lasting for 147 days under DLFG, as compared to 115 days under DLFG and only 90 days under OF cultivation. The cumulative temperature under DLFG cultivation (2 592.1 ℃) also significantly increased, compared to SLFG and OF cultivation, with the increase reaching 74.3%. The phenological and maturation periods for M. rubra were significantly earlier under these forcing cultivations, with the maturation periods of DLFG and SLFG being 40 and 22 days earlier than those of OF cultivation. The harvest time under DLFG and SLFG cultivation was up to 57 days, which was 3.4 times longer than that under OF cultivation. These forcing cultivation methods also significantly improved single fruit weight, soluble solid and flavonoid contents, taste, nutritional value, as well as storage and transportation capacity. Although these forcing cultivation methods reduced light intensity, the available light was sufficient to meet the needs for these bayberry trees. Thus, the normal plant growth and photosynthetic activity were not adversely impacted under either DLFG or SLFG cultivation. Moreover, the leaf morphology, including leaf length, width, area, perimeter, relative chlorophyll content, and chlorophyll fluorescence parameters increased with both Biqizhong and Dongkui. In addition, forcing cultivation significantly improved the fruit yields and quality. The results displayed that the average yields of Biqizhong under DLFG and SLFG cultivation were 2 312.5 kg · 666.7 m-2 and 2 261.7 kg · 666.7 m- 2, respectively, 40.0% and 37.0% higher than those under OF cultivation. Furthermore, the average commercial fruit rates were 85.1% and 79.8% under DLFG and SLFG cultivation, 2.8- and 2.6-times higher than those under OF cultivation. Similarly, the average yields of Dongkui under DLFG and SLFG cultivation were 1 655.2 kg · 666.7 m-2 and 1 568.5 kg · 666.7 m-2, respectively, 2.9- and 2.8-times higher than those under OF cultivation. The commodity fruit rates and economic benefits surpassed 1.6- and 7.1-fold under DLFG and SLFG cultivation, respectively. 【Conclusion】The forcing cultivation of M. rubra is an effective technique that can significantly advance the maturity period, extend the harvest period, improve fruit quality and promote economic benefits, without affecting the normal growth of M. rubra. Based on the above benefis of DLFG and SLFG cultivation, it is of a great value to further popularize and apply these bayberry cultivation techniques throughout China. © 2023 Journal of Fruit Science. All rights reserved.     

杨梅产地保鲜处理与新型贮运包装的研究及应用

杨梅果实代谢旺盛、含水率高且无外果皮保护,在采收、运输和销售过程中易遭受机械损伤及霉菌侵染,进而导致其品质劣变,严重制约杨梅产业的发展.本文概述了产地保鲜技术(保鲜剂、预冷、短波照射以及静电场等)和贮运包装(减震包装、气调包装和蓄冷包装)对杨梅鲜果采后品质的影响,通过分析引起杨梅品质劣变的主要因素,提出"低温环境"+"缓震处理"+"气调技术"三维一体的栅栏保鲜技术将成为杨梅鲜果的保鲜研究重点.     

黔产红托竹荪基地土壤-红托竹荪体系矿质元素含量及相关性分析

掌握织金县红托竹荪中矿质元素的含量水平,通过适当调控土壤,利于红托竹荪生长,也可为红托竹荪的营养性和安全性评价提供参考依据。通过对基地土壤-红托竹荪矿质元素钾(K)、钙(Ca)、铁(Fe)、锌(Zn)、硒(Se)的测定,并对其进行相关性分析。结果表明：土壤中矿质元素平均含量大小为Fe>K>Ca>Zn>Se,红托竹荪中矿质元素平均含量从高到低依次为K>Ca>Fe>Zn>Se;富集能力最强的为钾元素;基地土壤-红托竹荪间的矿质元素相关性统计显示矿质元素Fe与土壤pH呈显著负相关(P<0.05);土壤(Ca)-红托竹荪(Ca、Zn)、土壤(Se)-红托竹荪(Se)为极显著正相关(P<0.01);土壤(K)-红托竹荪(Fe、Zn)、土壤(Fe)-红托竹荪(Fe)为显著正相关(P<0.05)。基地土壤间矿质元素的相关关系为：K-Fe、K-Se、Ca-Zn呈极显著正相关;K-Ca、Ca-Se在0.05水平上呈显著正相关;Ca-Fe、K-Fe呈极显著负相关。红托竹荪中矿质元素K-Zn、Ca-Fe呈显著正相关;K-Ca、K-Fe、Ca-Zn呈极显著正相关。其他矿质元素则无显著相关关系。在土壤中添加一定浓度的钾、钙元素可能促进红托竹荪对其他矿质元素的吸收,一定程度上可能提高竹荪的品质。     

杨梅凋萎病树的硼元素分配以及施硼对发病率的影响

凋萎病是杨梅产业的重大病害，为研究凋萎病树硼元素分配的变化和施硼对发病率的影响，本文测定病树与健康树(CK)的根、枝和叶等部位的硼含量、根际土壤速效硼含量，并且设计兑水浇施1.5、3.0、6.0、9.0 g/m2硼砂至杨梅苗圃地，0.75、1.5、3.0和4.5 g/m2成年树滴水线沟施硼砂，不施硼砂的作对照，调查施硼对凋萎病发生率。结果表明，凋萎病的发生严重影响了硼在杨梅树体内的吸收和分布。病树上有病症嫩梢的干枯叶片、没有病症的嫩梢叶片和老龄叶片的硼含量分别比CK显著低8.11%、6.04%和7.56%，病树表现症状的嫩梢枝皮、不表现症状的嫩梢枝皮和根部皮硼含量分别比CK显著高7.94%、9.76%和11.77%，病树根际土壤的速效硼含量比CK显著高29.03%，差异显著；病树无病症嫩梢枝干和根部干硼含量低于CK。9 g/m2硼砂处理杨梅苗木发病率比对照高7.4%，1.5 g/m2硼砂处理成年杨梅树发病率比对照降低7.6%，其他苗圃地和成年树处理发病率均无显著变化。本文研究结果将为开发杨梅凋萎病的综合防控技术提供理论支持。     

减压贮藏对杨梅果实采后品质的影响

为探讨杨梅果实在减压条件下的贮藏效果,以“安海变”杨梅为试材,对其进行减压(0.05 MPa)处理,并于2~4℃下贮藏,定期观察杨梅果实采后品质的变化,同时对果实呼吸强度、可溶性固形物(TSS)、总糖、可滴定酸、pH、失重率、好果率进行分析对比。结果表明:减压处理能有效抑制杨梅果实冷藏期间的呼吸强度,延缓其TSS、总糖、可滴定酸含量的下降和失重率的上升,提高采后杨梅贮藏效果,使其在贮藏第16天时好果率仍保持在90%以上。这说明减压贮藏能较好地保持杨梅果实采后品质,延长其贮藏期、供应期。