Temporal dynamics of nutrient and carbohydrate distribution during crop cycles of Rosa spp. ‘Kardinal’ in response to light availability

Rose plants that are flush harvested exhibit episodic growth patterns. During these crop cycles little biomass accumulation occurs immediately following harvest; and as new shoots emerge a period of rapid shoot growth and biomass accumulation occurs. The temporal changes in whole-plant nutrient and carbohydrate distribution during these crop cycles and the role of storage in new shoot growth are not well documented. The objective of this project was to quantify N, P, K, and total non-structural carbohydrates (TNC) distribution in roots, base stems, base leaves, and new shoots during crop cycles in response to light availability. Plants were grown in solution culture under high or low light (mean daily light integral 45.3 or 13.1 mol m⁻² d⁻¹, respectively) during 30–35 day crop cycles. Every five days destructive sampling was used to determine biomass and N, P, K, and TNC concentration of rose plant compartments. N and TNC accumulated in base plant compartments during the first ten days of the crop cycles. N, P, K, and TNC in base plant compartments declined during days 10–25 during a crop cycle concurrent with the rapid growth of flower shoots. N, P, and K storage in base plant parts represents 27, 22, and 24% of the potential N, P, and K required by flower shoots under high light; and 19, 21, and 22% of requirements under low light. TNC storage in base plant parts represents 4–10% of the final biomass of flower shoots. Mobilization of N, P, K, and TNC stored from base plant parts appears to be important during the stage of rapid flower shoot growth when absorption by roots or photosynthesis by shoots was insufficient to meet flower shoot demands. Plant carbohydrate status was improved under high light conditions; storage of N and TNC declined under low light.     

Evaluation of acaricide-treated string curtains for control of two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae) on greenhouse roses and impact of the string curtain on the predatory mite Phytoseiulus persimilis Athias-Henriot (Acari: Phytoseiidae)

Foliar sprays of pesticides are frequently used to control two-spotted mites on rose flowers, but these also destroy predatory mites and pose a high risk of contamination for humans and the environment. Using a novel approach to avoid spray applications on rose plants, modified acaricide-treated string curtains were adapted to control the pest. Two main aims of this study were: (i) to identify the lethal concentration of string curtains treated with propargite, dicofol, flufenoxuron, acrinathrin or tau-fluvalinate (τ-fluvalinate) on Tetranychus urticae, and (ii) to test the design (feasibility) and efficiency of the string curtains to trap the phytophagous mites on the plants during their circadian migration. Bioassay results in the lab confirmed T. urticae circadian migration, toxicity of the five kinds of treated string curtains and a concentration-dependent repellent effect of each chemical on T. urticae females. Of the two products tested in the field, dicofol was more effective than acrinathrin in controlling T. urticae compared to an acaricidal spray of the same products. The effect of acaricide-treated string curtain use on Phytoseiulus persimilis did not differ significantly from the control. The string curtain technique proved to be effective, but because of some biotic and abiotic constraints and the low economic threshold of mites, even for the commercialized high canopy stem roses, the present device could be more appropriate for another horticultural crop, e.g. tomato.     

不同品种玫瑰花中黄酮的提取及抗氧化性

研究北京地区栽种的5种不同品种玫瑰花中黄酮含量及抗氧化性能。设计正交试验,确定玫瑰花黄酮的最佳提取条件,采用邻苯三酚自氧化体系和二苯代苦味酰自由基(DPPH)体系进行抗氧化性研究。试验结果表明:最佳提取条件为,乙醇体积分数65%,提取温度70℃,提取时间1.5h,液料比(V(乙醇(φ=65%))∶m(玫瑰花粉))30mL∶1g;妙峰山玫瑰中黄酮含量最高,为66.040mg/g;5种玫瑰花均表现出较强的清除超氧阴离子自由基(O2-.)和DPPH自由基(DPPH.)的能力,且其清除能力和黄酮提取液浓度呈正相关;其中妙峰山玫瑰中总黄酮的清除能力最强,其清除O2-.和DPPH.的半抑制浓度(IC50)相应为0.067和0.136mg/mL,但与维生素C(VC)相比,其抗氧化能力略低于VC。     

不同轻基质配方对边坡绿化植物——藤本月季生长指标的影响研究

选用典型的边坡绿化植物藤本月季为供试材料,栽培基质选用泥炭、蛭石和珍珠岩。将3种基质按不同比例进行混合,与试验地原土进行对照,共设4种配方。同时分别测定4种配方的理化性质,有效含水量以及藤本月季的生长指标。通过相关分析法和主成分分析法最终确定了最优的轻基质配方为泥炭与珍珠岩按体积比2∶1混合为最佳。     

北京奥运月季花期调控

月季花期调控和增加花量的研究是通过采用不同修剪强度、修剪时间、施肥水平等方式使北京城市栽培的月季于奥运会期间持续开花,同时增加花量。试验结果表明:修剪强度对月季花期调控和增加花量具有较大的效应,采用强修剪、中度修剪和弱修剪相结合的修剪方式有利于调控花期;修剪时间受气温、开花周期和修剪强度等多因素影响;施肥数量和施肥种类影响月季开花的质量、数量和抗逆性。温度是藤本月季花期调控的最大影响因子,不同品种受温度影响的程度存在差异。     

丰花月季的引种试验报告

经过5年的丰花月季引种试验,研究了4个丰花月季品种的物候期、花枝生长特性和开花习性、开花品质、抗病性、抗虫性、株型和长势。结果表明,最适合武汉地区、华中地区露地种植的丰花月季品种是曼海姆,其次是马蒂尔德。     

Effects of air humidity and K/Ca ratio in the nutrient supply on growth and postharvest characteristics of cut roses

Single node cuttings with one mature leaf were taken from the rose cv. Baroness and rooted in water culture. The rooted plants were grown in nutrient solutions and subjected to two levels of relative air humidity (RH): high (90%) and moderate (70%), in combination with high (12/1), medium (1/1) and low (1/5) K/Ca ratios in the nutrient solution. High RH plants accumulated less Ca in leaves and flowers than moderate RH plants. Roses grown at moderate RH had a longer postharvest life than high RH roses, irrespective of the K/Ca ratio of the nutrient solution. In general, a high K/Ca ratio had a negative impact on postharvest life. When grown at a high K/Ca ratio the ornamental value declined rapidly, mainly due to the appearance of necrotic petals as well as chlorotic and necrotic areas on the leaves. Bent neck occurred only with high RH plants but changes in the K/Ca ratio had no differential effect. Dry spots and brittle leaves were observed on high RH roses, and the occurrence increased with increased K/Ca ratio in the nutrient solution. Stomatal conductance increased in parallel with increases in RH and K/Ca ratio when measured on intact roses placed in dry air (40% RH).     

3种藤本植物耐热性生理生化指标初探

为丰富城市河道藤本植物品种、美化景观,选择藤本月季、龙须藤和辟荔3种植物进行耐热指标研究。测定不同热处理条件下3种植物叶片的相对含水量、含水量、细胞膜透性和叶绿素含量。结果表明,叶片的相对含水量、含水量、细胞膜透性和叶绿素含量指标变化可用于藤本月季、龙须藤和辟荔3种植物的叶片耐热性评价;龙须藤较耐热,辟荔次之,藤本月季较不耐热。     

丰花月季嫁接繁殖技术研究

用4种嫁接方法研究了2个丰花月季品种曼海姆(Sohlossmannieim)和马蒂尔德(Matilda)的嫁接繁殖技术。结果表明:T形芽接法的最适宜时期是5、10月;切接法的最适宜时期是6、9、10月,且取顶端芽(不含顶芽)作为接穗;劈接法的最适宜时期是4、5、10月;生长季绿枝劈接法(绿枝劈接法)的最适宜时期是4、5月。4种嫁接方法中,均以8月嫁接成活率最低。     

丰花月季扦插繁殖技术研究

用茎 (枝 )插法研究了 2个丰花月季品种曼海姆 (Sohlossmannieim)和马蒂尔德 (Matilda)的扦插繁殖技术。结果表明 :对枝条进行环剥处理 ,只要技术熟练 ,不用任何激素 ,扦插成活率可达 90 %以上 ;用嫩枝和硬枝扦插时 ,将插穗基部用浓度为 80 0～ 10 0 0ng/L的ABT生根剂浸泡 5min ,可提高丰花月季的成活率 ,且获得的扦插苗质量较好。