Antimycotic Screening of 58 Malaysian Plants against Plant Pathogens

Ethanolic extracts of 58 Malaysian plants belonging to 24 different families were screened for antifungal activity against seven plant pathogens using the filter paper disc diffusion technique. Two varieties of Piper betle, showed strong activity against all the pathogens tested (Colletotrichum capsici, Fusarium pallidoroseum, Botryodiplodia theobromae, Alternaria alternata, Penicillium citrinum, Phomopsis caricae-papayae and Aspergillus niger), with inhibition diameters significantly (P<0·01) bigger than 2·5 mg ml⁻¹ prochloraz or 10 mg ml⁻¹ clotrimazole. The minimum inhibitory concentrations of the ethanolic extracts of P. betle against these plant pathogens ranged between 0·01 mg ml⁻¹ and 1 mg ml⁻¹. Thirty-four other plants (Kucing gala, Limau batik, Bertholletia excelsa, Bixa orellana, Caesalpinia pulcherrima, Cerbera odollam (fruits and leaves), Colocasia gigantea, Curcuma domestica, Curcuma manga, Derris eliptica, Elephantopus scaber, Eleusine indica, Eugenia polyantha, Euphorbia hirta, Euphorbia tirucalli, Gardenia florida, Hedyotis auricularia, Hibiscus rosa-sinensis, Juniperus chinensis (three varieties), Lawsonia inermis, Lecythis ollaria, Mentha arvensis, Mimusops elengi, Ocimum sanctum, Phyllanthus niruri, Piper nigrum, Piperomia pellucida, Pedilanthus tithymaloides, Polygonum minus, Spondias dulcis, Solanum nigrum, Tinospora tuberculata) showed selective antifungal activity, while 21 species were inactive.     

油炸处理对胡椒鲜果中精油成分的影响

为研究油炸处理对胡椒鲜果中胡椒精油化学成分的影响,从不同油炸料油比、油炸温度和油炸时间进行研究。经检测分析鉴定出未经油炸处理胡椒鲜果精油中18 种化学物质,料油比1:1、1:1.5、1:2、1:2.5 和1:3 时胡椒精油分别检测出28、22、27、24 和25 种化学物质;油炸温度为90、100、110、120、130℃时胡椒精油分别鉴定出21、26、22、25 和23 种化学物质;油炸时间为1、2、3、4、5 min 时胡椒精油分别含有29、22、23、21 和25 种化学物质。研究发现,不同油炸处理均使胡椒鲜果精油的化学物质成分增加,主要化学成分为石竹烯、3-蒈烯、D-柠檬烯、左旋-β-蒎烯、α-水芹烯和α-蒎烯等。     

土壤水分对胡椒实生苗生长和活性氧代谢的影响

为探讨土壤水分对胡椒生长和叶片活性氧代谢的影响,以胡椒实生苗为研究对象,设置5%、10%、15%、20%和25%共5个土壤质量含水量处理,测定试验开始后第1、3、5、8、14天不同处理的抗氧化酶活性、膜脂过氧化产物及第14天时植株相关生长指标,以期明确适宜胡椒生长的土壤含水量范围。结果表明：1～3 d内,5%土壤水分处理表现出胡椒叶片抗氧化酶活性显著高于其他处理,15%和20%处理最小,受到的胁迫程度最低;而3 d后,由于5%处理胡椒叶片失水严重,抗氧化酶活性显著降低,10%处理仍呈现较高水平;总体趋势上,15%、20%和25%处理的膜脂过氧化程度最低,生长状况也最好。上述结果表明,适宜胡椒生长的土壤质量含水量范围为15%～25%,土壤水分含量过低形成的干旱胁迫会影响胡椒生长,降低叶片抗氧化能力,加重膜脂过氧化伤害程度。     

胡椒属野生近缘种‘芦子’鉴定评价及创新利用

以大叶种胡椒(Type Lampong)为对照,对胡椒属野生近缘种质资源‘芦子’(Piper betle L.)的植物学性状、农艺性状及抗逆性状(抗寒、抗病)等主要性状进行鉴定评价。结果表明：野生近缘种质‘芦子’长势强,冠幅大,果穗长,座果率高,抗寒、抗病能力较强,农艺性状及抗性明显优异大叶种胡椒;通过对‘芦子’种质资源的无性繁殖品种改良技术进行探究,说明 ‘芦子’野生近缘种质资源是胡椒品种改良较好的中间材料,将为胡椒种质资源创新利用及胡椒产业发展奠定良好的基因基础。     

Spice crops agroforestry systems in the East Usambara Mountains,Tanzania: growth analysis

A scarcity of cultivation land calls for more intensive and productive land use in the East Usambara Mountains in NE Tanzania. Spice crops could generate cash in higher parts of the mountains, but the present cultivation methods are depleting the valuable forest resources. The trial was established at the end of 2000 to find out how the two popular cash crops, cardamom (Elettaria cardamomum (L.) Maton.) and black pepper (Piper nigrum L.), normally grown under the natural forest, will produce in intensive agroforestry system with two multipurpose farm trees, Grevillea robusta A.Cunn. and nitrogen fixing Gliricidia sepium Jacq. Results from 6 years showed that cardamom produced better with grevillea than in natural forest; 5.5 times more in the fourth year than the average in the area. The Land Equivalent Ratios for black pepper and cardamom showed that pepper intercropped with grevillea produced 3.9 times more than in monoculture whereas cardamom intercropped with grevillea and pepper produced 2.3 times more than in monoculture. Gliricidia improved the nitrogen and organic matter content of the soil over the levels found in natural forest. Soil acidity was, however, preventing the plants from using the available mineral nutrients more effectively.     

我国胡椒产业现状及发展对策

从产销、种质资源、栽培管理和产品加工等方面分析我国胡椒产业现状,展望胡椒产业发展前景,并针对性的提出发展对策,以期为广大胡椒科研生产工作者提供参考。     

卡瓦脂质体纳米颗粒制备及其稳定性的研究

目的制备包载卡瓦的脂质体纳米颗粒并研究其稳定性。方法采用旋转薄膜蒸发法制备卡瓦纳米制剂,并对其形貌、大小等进行表征,考察纳米颗粒的稳定性。结果卡瓦脂质体纳米颗粒平均粒径为（99．7±7．6）nm,多分散系数为0．321±0.011,Zeta电位为（-33．9±2．3）mV,包封率为（83．32±0．34）％;纳米溶液于4℃下放置60d,其纳米粒外观、粒径及包封率无明显变化,差异均无统计学意义（P〉0．05）。结论卡瓦脂质体纳米颗粒的包封率较高,粒径分布均匀,稳定性良好,为卡瓦的新剂型开发提供了实验依据。     

海南胡椒属植物抗寒性评价

对10种海南胡椒属植物叶片进行-3,-5,-7℃低温处理后,采用电导仪法和硫代巴比妥酸法,分别测定低温低温胁迫对海南胡椒属植物叶片的相对电导率和丙二醛含量的影响,同时对其抗寒性进行评价。结果表明：蒌叶、山蒌、大叶蒟、复毛胡椒抗寒性较强,而大叶种胡椒和海南蒟的抗寒能力较弱。     

Concentrations of total nitrogen in squash,cucumber and melon in relation to growth,and to a piper‐steenbjerg effect

Abstract

Squash (Cucurbita pepo), cucumber (Cucranis sativus), and sweet melon (Cucumis dudain) were grown in sand cultures with N supply concentrations as the variable. For several reasons, total‐N values were found to be less satisfactory than NO ‐N for the purpose of determining the critical nitrogen concentration for maximum growth. Concentrations of total‐N in mature petioles were higher in plants severely deficient in N than in less deficient plants, characteristic of a Piper‐Steenbjerg effect.