Physiological responses of tomato roots grown in organ culture to iron-deficiency stress

Roots of the Fe-efficient tomato (Lycopersicon esculentum Mill., cultivar Floradel) were cultured in an inorganic medium supplemented with glycine, thiamine, pyridoxine, and nicotinic acid, with sucrose as an energy and carbon source. Iron was supplied as ferric hydroxyethylethylenediaminetriacetic acid (FeHEDTA) and the initial PH was 5.5. Root growth was limited when less than 40 μm FeHEDTA was supplied. Roots grown at lower Fe concentrations decreased the pH of the FCR assay medium to a greater extent than did roots grown at higher Fe concentrations. Cultured roots grown with 10 μm FeHEDTA had increased levels of ferric chelate reductase (FCR) activity compared to roots grown with either lower or higher concentrations of FeHEDTA. Low FCR activity of roots grown at 2.5 or 5 μm FeHEDTA was attributed either to impaired metabolism due to Fe-deficiency or the lack of sufficient Fe for enhanced FCR formation. Roots of hydroponically grown tomato plants exhibited typical increases in FCR activity with Fe-deficiency. Based on these preliminary results, cultured roots were found to exhibit similar Physiological responses to Fe-deficiency stress as intact root systems. Cultured roots should provide a useful system for the investigation of the role of the root in plant Fe-deficiency stress responses as previously suggested by Bienfait et al.(Plant Physiol., 83, 244–247, 1987).     

Nutrient Stress,Ecophysiological, and Metabolic Aspects of Olive Tree Cultivars

This research, aimed at evaluating stress on the olive tree, utilized cultivars ‘Meski’ and ‘Chetoui’ in regards to the removal of major elements such as nitrogen (N), phosphorus (P), magnesium (Mg), and potassium (K). The experiment was conducted under greenhouse conditions in hydroponics culture. Measurements of leaf area showed a non-substantial and weak effect due to phosphorus, potassium, or magnesium deficiency compared to nitrogen. The growth analysis of dry matter showed an early depressive effect of nitrogen deficiency and a similar, but less important effect concerning phosphorus.

The induced nutritional stresses showed an important increase in stomata resistance, caused primarily by nitrogen or potassium deficiency, accompanied by a reduction of chlorophyll concentration, which resulted from the removal of phosphorus, magnesium, and mainly nitrogen supply. Remarkable starch synthesis and storage was also revealed following nitrogen deficiency, but it was very weak after the suppression of magnesium, which may provoke a weakening of growth and development of these plants.     

光合细菌在种植业上的应用研究近展

就光合细菌(PSB)在提高粮食、果蔬及多种经济作物的产量,并改善其产品质量,提高植物抗病毒能力,增强果实耐贮性,促进土壤有益微生物增殖,改善土壤理化结构,减轻农药对植物的毒害和降解残留农药中的作用等研究近况作了较全面的叙述,并对其作用原理作了简要分析。     

植酸对霍山石斛类原球茎悬浮培养细胞生长和多糖合成的影响

研究了植酸对霍山石斛类原球茎悬浮培养细胞生长、多糖合成和培养基中主要营养成分消耗的影响,并分析了细胞中可溶性还原糖、可溶性蛋白质、丙二醛含量以及过氧化物酶和多酚氧化酶的活性。结果表明,植酸能抑制过氧化物酶和多酚氧化酶的活性,提高细胞活力,从而促进细胞生长和多糖合成,以2.5g/L浓度的植酸效果最好,培养36d时,类原球茎干重为29.4g/L,多糖产量为2.06g/L。动力学分析表明,添加2.5g/L的植酸还有利于碳、氮、磷等营养物质的吸收。     

成年鲁西牛肌内前脂肪细胞的分离培养

建立牛肌内前脂肪细胞体外培养方法，旨在更深入地研究组成肌肉内脂肪组织的肌内前脂肪细胞的增殖分化特性及其影响因素。选取来自成年育肥鲁西黄牛第6与第7肋骨间的肌肉内脂肪组织，利用Ⅰ型胶原酶消化法分离获得牛肌内前脂肪细胞。培养出的细胞成分均一，增殖旺盛，分化率高，经形态学动态变化观察、生长曲线、油红O脂肪染色提取法及对胰岛素和地塞米松反应的测定，证明是功能活跃的前脂肪细胞，并在体外重现了其增殖分化过程，同时经染色体核型分析证明体外培养的细胞倍性正常，可以用于后续研究。本试验成功分离得到了成年育肥牛肌内前脂肪细胞，这为下一步研究肌内脂肪的沉积机制，改善牛肉品质奠定了基础。     

Effect of nutrient solution salinity and ionic concentration on parsley (Petroselinum crispum Mill.) essential oil yield and content

The growth and essential oil (EO) production of parsley were evaluated in response to salinity and nutrient solution concentrations in a soilless culture. Parsley plants that were 60 days old were potted in a coconut fiber and peat moss medium and were treated with four different nutrient solutions, including T1, T2, T3 and T4. The T1 nutrient solution was the standard, the T2 and T3 solutions contained incremental macronutrient concentrations with an electrical conductivity (EC) of up to 2.2 and 3.2 dS m^?1, respectively, and the T4 solution was the same as T2 but with sodium chloride (NaCl) and an incremental macronutrient concentration with an EC of 3.2 dS m^?1. Next, these plants were grown for 90 days in a greenhouse with natural daylight in Nador, Morocco. Shoot and root growth significant decreased with increasing EC. However, the salinity that resulted from the addition of NaCl did not affect plant growth in the nutrient solutions. The optimum obtained growth and EO production were 1.2 and 2.2 dS m^?1, respectively. Consequently, the optimum EC value (based on the EO production) of parsley in the soilless culture was 1.2–2.2 dS m^?1.     

木门百合子房组织培养研究

以百合新品种木门(Conca D'or)的子房为材料,开展组织培养研究。结果表明,诱导愈伤组织的最适培养基为MS 6-BA1.0mg/L NAA0.5mg/L,其诱导率为76%;芽分化最适培养基为MS 6-BA1.0mg/L NAA0.1mg/L,其分化率达到82.5%;生根培养基为MS,生根率达100%。     

家兔原始卵泡卵母细胞体外发育的培养体系研究

本研究根据家兔卵巢的发育特征初步探讨了家兔卵巢卵母细胞体外发育的培养体系。采集新生或30日龄家兔卵巢在不同培养液中培养,并分析家兔卵母细胞的体外发生与成熟情况与体内正常发育的兔卵巢卵母细胞之间的差异,来筛选和优化家兔卵巢卵母细胞的体外培养体系。本试验从高糖DMEM、FSH浓度、BSA/血清等3个方面来筛选较好的培养条件,结果表明:①不添加高糖DMEM的M199培养液与添加的相比,卵巢上卵母细胞数量要多,但随着培养时间的延长,组织块上卵母细胞的形态会变得不清楚;②家兔卵巢组织在FSH浓度为50和100m IU/m l、添加血清的DMEM/F12培养液中生长较好,体外培养24d后,卵母细胞数量多,直径增加到65μm;③与添加BSA的培养液相比,添加血清的培养液中的卵巢卵母细胞生长状态较好,体外培养28d后,卵母细胞数量多,并且直径可达65μm。     

乡村旅游饮食文化资源开发研究

乡村饮食文化资源包括各类食物及其加工制品和各种饮食礼俗,它有着丰富的类型,并具有满足基本生理需要、显著自然本色和突出地域特色等特征,在乡村旅游中有着重要的地位和开发价值。在进行乡村旅游饮食文化资源的深度开发时,要加强乡村饮食文化挖掘,保持乡村饮食的“自然本味”,突出乡村饮食的文化包装。     

耐冬山茶愈伤组织诱导研究

重点探讨耐冬山茶愈伤组织诱导过程中不同植物生长调节剂、培养基pH值、不同培养基及不同类型外植体对愈伤组织诱导效应的影响。研究结果表明:MS+6-BA 2.0 mg.L-1+2,4-D 0.5 mg.L-1培养基是耐冬山茶愈伤组织诱导的最佳培养基;耐冬山茶愈伤组织诱导培养基pH值以5.5较为合适;耐冬山茶叶柄作为外植体,诱导率和生长状况最佳。