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991.
[目的]对超声波辅助提取资兴柑橘皮中总黄酮的工艺进行优化。[方法]利用超声波辅助提取资兴柑橘皮中的总黄酮,考察了乙醇浓度、料液比、提取温度、提取时间4个因素对总黄酮提取率的影响,通过单因素试验和正交试验确定了提取的最佳工艺条件。[结果]资兴柑橘皮总黄酮的最佳提取工艺为在固定超声波功率为600 W的条件下,乙醇浓度40%,料液比1∶30 g/ml,提取温度50℃,提取时间30 min,此时总黄酮的提取率可达1.824%。[结论]用超声波辅助提取资兴柑橘皮总黄酮提高了提取的速度和得率,具有不产生噪音、能耗低、效率高、不破坏有效成分等优点,该研究为柑橘皮总黄酮的进一步开发利用奠定了试验基础。 相似文献
992.
993.
香橼不同品系耐寒性的研究 总被引:1,自引:0,他引:1
以24个果实性状优良的香橼(Citrus medica L.)品系为试材,采用田间鉴定法、细胞膜透性鉴定法,评价其耐寒性差异,并以耐寒性强、中、弱3类有代表性的10个品系进行人工低温处理,进一步研究其耐寒生理特性。结果表明:越冬期间24个品系寒害指数范围为2.00 ~ 3.40,半致死温度(LT50)范围为﹣14.84 ~﹣7.07 ℃。分别根据寒害指数和LT50进行聚类分析,评价了24个香橼品系耐寒性强弱,其中,耐寒性强的品系有春江4#、春江5#、春江6#、新世纪9#、新世纪10#、香橼4#;其次为春江1#、春江2#、春江3#、春江8#、香橼1#、香橼2#、香橼5#、香橼6#、香橼7#、新世纪1#、新世纪3#、新世纪4#、新世纪5#、新世纪6#、新世纪7#、新世纪8#;耐寒性弱的品系为春江7#、新世纪2#。随处理温度降低,10个香橼品系叶片的丙二醛(MDA)、脯氨酸(Pro)、可溶性蛋白质含量及超氧化物歧化酶(SOD)活性总体均表现为先上升而后下降的趋势,其中耐寒性强的品系MDA含量低,Pro、可溶性蛋白质含量及SOD活性高;反之,耐寒性弱的品系MDA含量高,Pro、可溶性蛋白质含量及SOD活性低。 相似文献
994.
【目的】为研究红橘(citrus reticulate)精油对橘小实蝇(Bactrocera dorsalis)产卵行为的影响。【方法】用浸泡法测试不同浓度红橘精油处理后杧果上的橘小实蝇产卵量,并对红橘精油进行GC-MS分析。【结果】结果表明,经不同浓度红橘精油处理的杧果上的橘小实蝇着卵量均显著高于对照,且随着红橘精油浓度的提高其产卵量升高。红橘精油主要成分为柠檬烯,松油烯,月桂烯,α-蒎烯,4-异丙基甲苯,芳樟醇等。【结论】初步确定,红橘精油对橘小实蝇产卵具有显著的引诱活性;这些主要成分可能是红橘精油引诱橘小实蝇产卵的主要物质。 相似文献
995.
Agroecological transition refers to the adoption by farmers of practices based on on-farm biological processes rather than imported or non-renewable inputs. Drawing from a comprehensive survey of 31 diversified farms cultivating citrus on Réunion Island (Indian Ocean, France), this study aims to understand the diverse dynamics in farmers’ agroecological transitions and to identify the factors and processes driving farmers’ choices. The analysis considers both the current protection, fertilization and weed control practices implemented by farmers in their orchards and the trajectories of change they have followed over the last thirty years. Orchard management was categorized according to the kind of inputs mobilized (i.e., “synthetic inputs”, “alternative off-farm inputs” and “alternative on-farm inputs”). Diverse managements were observed, targeting security, autonomy, ecology or simplicity. The six types of practice trajectories identified illustrate the diverse and incremental nature of agroecological transition. Drawing from these results, drivers of alternative practice adoption and lock-in effects in synthetic input reliance were characterized. Internal drivers, depending directly on the farmer and his/her farm, included the characteristics of the orchard and its environment, the labor force, and the farmer’s environmental concerns. External drivers included local citrus markets, public legislation, access to extension services, the organization of input supply and the social environment. The combination of these internal and external drivers at the farm level makes each farm relatively unique. However, three factors determine the main differences in practices: the marketing channel used, the farmer’s environmental objectives, and the farmer’s economic behavior, which is linked to the weight of the crop activity in farm revenue. Understanding farmers’ points of view and decisions regarding agroecological transition deserves the attention of scientists, agricultural advisors and policy makers when designing innovative cropping systems, new support methodologies and incentives to respond effectively to farmers’ objectives and contexts of action. 相似文献
996.
Yongrui He Shanchun Chen Aihong Peng Xiuping Zou Lanzheng Xu Tiangang Lei Xiaofeng Liu Lixiao Yao 《Scientia Horticulturae》2011
Transgenic plants of Jincheng orange (Citrus sinensis Osbeck) and Newhall navel orange (C. sinensis Osbeck) containing antibacterial peptide genes Shiva A and Cecropin B were successfully obtained by a novel Agrobacterium tumefaciens-mediated transformation of the mature axillary buds. PCR and Southern blot analysis of the transgenic plants verified that the Shiva A and Cecropin B genes were integrated into the citrus genome. The transgenic plants began to blossom and bear fruit in the 2nd year after grafting on trifoliate orange (Poncirus trifoliata Raf) rootstock in greenhouse. Water-soluble extracts from transgenic citrus leaves exhibit in vitro suppressive effects on Xanthomonas axonopodis pv. citri, suggesting that the expressed products of Shiva A and Cecropin B in citrus retain their native antibacterial activities. Artificial inoculation in greenhouse and open field further indicates significantly increased resistance of transgenic plants to X. axonopodis pv. citri when compared with non-transgenic lines. No significant difference was found in the content of total soluble solids, total acidity, reduced sugar content and other fruit characteristics between transgenic and non-transgenic plants. In this present study, 11 transgenic lines were obtained from 40 transgenic lines, showing enhanced resistance to citrus canker disease. 相似文献
997.
Qiangming XIA Wei WANG Kaidong XIE Xiaomeng WU Xiuxin DENG Jude W. GROSSER Wenwu GUO 《农业科学与工程前沿(英文版)》2021,8(2):302
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Citrus is one of the most cultivated fruits in the world, and satsuma mandarin (Citrus unshiu Marc.) is a major cultivated citrus in Japan. Many excellent cultivars derived from satsuma mandarin have been released through the improvement of mandarins using a conventional breeding method. The citrus breeding program is a lengthy process owing to the long juvenility, and it is predicted that marker-assisted selection (MAS) will overcome the obstacle and improve the efficiency of conventional breeding methods. To promote citrus molecular breeding in Japan, a genetic mapping was initiated in 1987, and the experimental tools and resources necessary for citrus functional genomics have been developed in relation to the physiological analysis of satsuma mandarin. In this paper, we review the progress of citrus breeding and genome researches in Japan and report the studies on genetic mapping, expression sequence tag cataloguing, and molecular characterization of breeding characteristics, mainly in terms of the metabolism of bio-functional substances as well as factors relating to, for example, fruit quality, disease resistance, polyembryony, and flowering. 相似文献