走进色彩缤纷的涂料世界

涂料是涂于物体表面可形成连续性薄膜的具有保护、装饰或其他特殊功能的材料。其主要组成材料有成膜物、颜料填充物、稀释剂及添加剂等。涂料的种类繁多，有通用油漆及特种油漆。在园林建筑设计中应根据不同的使用环境、使用条件选择不同品种的涂料。用心研究并恰当应用涂料，世界将变得更美丽。     

Polyphenoloxidase activity and browning in fresh-cut ‘Rocha’ pear as affected by pH,phenolic substrates,and antibrowning additives

The effect of pH, phenolic substrates, and food additives on polyphenoloxidase (PPO) activity and on tissue browning was studied in fresh-cut ‘Rocha’ pear. Substrates 4-methylcatechol, caffeic acid, (+)-catechin hydrate, catechol, chlorogenic acid, dopamine hydrochloride, and pyrogallol, were prepared in citric acid-phosphate buffer at pHs ranging from 3.0 to 8.0. pH optima for PPO activity depended on the phenolic substrate. Activity was optimal at pH 5.0 for catechol and 4-methylcatechol; pH 6.0 for chlorogenic acid; pH 7.0 for dopamine, caffeic acid, and catechin; and pH 8.0 for pyrogallol. Discrepancies were observed between the pH dependency of PPO activity and browning, as assessed by objective color measurement. Significant correlations were obtained between enzyme activity and metric-hue difference (ΔH*) over the pH range 3.0–8.0 for four of the eight phenolics. Chlorogenic acid, the main PPO substrate in ‘Rocha’ pear, induced high tissue browning but very low PPO activity at pH 3.0–4.0. Chemical inhibition of PPO was tested using catechol as substrate, and buffer solutions containing 250 mM Ca²⁺ in four salts (ascorbate, chloride, lactate and propionate), 57 mM ascorbic acid, 61 mM N-acetyl-l-cysteine and 3 mM 4-hexylresorcinol. PPO inhibition by additives was affected by the pH of the buffer, and was more effective with ascorbic acid, N-acetyl-l-cysteine and calcium ascorbate. It was concluded that inferences on tissue browning based on PPO activity can be misleading. Measurement of tissue color is proposed as a reliable means to assess the antibrowning effectiveness of additives and the pH of additives for cut pear should be corrected to reduce the browning potential.     

观赏型文冠果新品种花期颜色特征及其表型稳定性研究

'金花文冠'是笔者课题组前期选育的花期金黄色观赏型文冠果新种质,试验以'金花文冠'母株及其嫁接繁殖无性系植株为研究材料,以山西太谷当地实生植株('G13')为对照,通过形态特征和物候期观测、花和幼叶高光谱反射特征和色素含量对比分析,旨在阐明'金花文冠'的花色特性和表型稳定性.结果表明:(1)'金花文冠'母株和嫁接繁殖无...     

无絮彩叶杨‘中山彩韵’在苏北泗阳县地区的引种栽培试验

为了探索彩叶杨‘中山彩韵’能否适应在江苏省泗阳县地区高湿环境下繁殖栽培,将‘中山彩韵’引种到江苏泗阳县成子湖地区,以泗阳当地种植的南林95杨无性系为对照并进行了多方面观察研究。通过2a的栽培和观测,结果表明,‘中山彩韵’在江苏泗阳县成子湖地区容易繁殖,色彩鲜艳、稳定,但在高湿环境下也存在生长较慢、病虫害严重等问题,在泗阳地区栽培需精细管理。     

华南彩叶植物及其园林应用

近些年来由于多种类型彩叶植物的出现。暴露了现有的彩叶植物概念的局限性。通过对彩叶植物的深入调查观察，综合其特征，文章提出了新的彩叶植物概念；并就华南地区彩叶植物种类的多样性，详述了该区常见彩叶植物的配置方式以及存在问题．这将利于城市园林景观的美化和优化。     

不同突变体异色瓢虫取食人工饲料的适合度研究

旨在研究两个稳定遗传的异色瓢虫体色突变体（黑化ML和浅色GR）在取食人工饲料后的生物学表现是否存在差异。以存活率、发育时间、新羽化成虫体质量及繁殖力作为适合度参数来进行评价，并与野生型（WT,对照）进行比较。结果表明：黑化型的异色瓢虫存活率在1龄高达100%，在4龄和蛹期均为77%，显著高于浅色型；此外，黑化型的蛹均能正常羽化，而浅色和野生型的羽化率分别为64.3%和78.8%，且部分新羽化成虫鞘翅畸形。黑化型3龄幼虫（5.5 d）及总发育历期（27.4 d）均显著长于浅色（4.8 d、25.9 d）和野生型（4.9 d、24.5 d），所得新羽化雌雄成虫体质量均显著高于浅色型。3种表型异色瓢虫的日均产卵量和孵化率均无显著性差异。上述结果表明，异色瓢虫黑化突变体幼虫取食人工饲料后的适合度明显优于浅色突变体及野生型。     

水稻类病斑突变体lmm7的鉴定与基因定位

【目的】对水稻类病斑突变体的研究有助于解析其与植物生长和防御反应的关系。【方法】本研究在粳稻品系FI135胚培养过程中获得了1个类病斑突变体lmm7(lesion mimic mutant 7)。通过对其进行系统的表型鉴定、农艺性状考查、超微结构观察、生理学特性分析，阐明LMM7基因对植物生长的调控。通过病原菌抗性鉴定，明确lmm7对植物防御反应的影响。利用9311B与突变体lmm7杂交所得F₂群体对该突变体进行了遗传分析和基因精细定位。【结果】该突变体苗期表型正常，分蘖初期，植株基部叶片从叶尖开始不断出现褐色斑点，并向整株扩散，且斑点数目随植株生长不断增加。与野生型相比，突变体的株高、穗长、有效穗数、每穗粒数、结实率及剑叶长宽都显著降低，但籽粒性状和抽穗期没有显著性差异。遮光处理表明，突变体lmm7的表型受到光照诱导，抽穗期突变体lmm7叶肉细胞严重失绿，光合色素含量显著降低。组织化学分析表明，突变体病斑处的H₂O₂含量显著升高。透射电镜观察结果表明，突变体lmm7叶肉细胞的叶绿体数目减少，叶绿体类囊体片层结构严重受损，细胞器肿胀解体，并出现大量嗜锇小体，同时病斑内部和周围区域积累了大量的ROS。抗性鉴定结果显示突变体lmm7稻瘟病抗性水平显著高于野生型。遗传分析表明lmm7的突变表型受单个隐性基因控制。利用图位克隆的方法，目的基因被定位于水稻第7染色体短臂两InDel标记7B35和7B43之间，区间范围约260 kb。测序结果表明该区间内候选基因LOC_Os07g0203700第2891位碱基T发生了单碱基缺失，导致后续移码突变及翻译提前终止。【结论】lmm7与spl5互为等位基因，其突变抑制了植株的生长，同时增强了对稻瘟病的抗性。     

UV-C light inactivation kinetics of Penicillium expansum on pear surfaces: Influence on physicochemical and sensory quality during storage

UV-C inactivation kinetic data of Penicillium expansum on intact and wounded pear disks were determined. P. expansum conidia (0.5 mL, 1.6 × 10⁷ CFU/mL) were spot inoculated onto intact and wounded pear tissue with skin (excised disks), treated with UV-C doses ranging 0.101–3.06 kJ/m² at 23 °C and surviving conidia were enumerated. Changes in selected physicochemical parameters and sensory quality following UV-C treatment of whole pears were determined immediately after treatment, and 4 and 8 weeks of storage at 4 °C. A greater UV-C intensity was required for similar inactivation levels of P. expansum populations on wounded pear disks (3.1 kJ/m² for 2.7 log reduction) compared to intact pear disks (1.7 kJ/m² for 2.8 log reduction). No significant difference in % weight loss, or soluble solids content and texture was observed between UV-C treated and untreated pears. However, browning was observed on UV-C treated pear surfaces after 4 and 8 weeks along with changes in flavor and texture. An increase in consumer preference was noticed for the untreated control pears after 4 weeks storage.     

8个彩色马铃薯品种在阜南县适应性比较试验

为了丰富本地马铃薯品种资源,筛选出适宜本地土壤和气候类型彩色马铃薯品种,本单位引进了8个彩色马铃薯品种在阜南县开展适应性比较试验。结果表明,徽薯5号、红美和黑金刚3个品种表现较好。其中徽薯5号为红皮白肉,平均产量达48854.5 kg/hm2,比对照增产52.15%,商品薯率达86%。红美为红皮红肉,平均产量36418.2 kg/hm2,比对照增产13.42%,商品薯率达91%。黑金刚为紫皮紫肉,平均产量达32945.5 kg/hm2,比对照增产2.6%。本试验结果为阜南县彩色马铃薯品种选择提供参考。     

生长于墨西哥本土生活的景观——解读路易斯·巴拉甘

通过对墨西哥建筑师路易斯·巴拉甘的介绍，分析了影响其设计思想的因素，解释了巴拉甘作品在很大程度上是受墨西哥本土文化的熏陶。此外，国际风格、乡土风格、巴拉甘童年时代的乡村生活以及设计师贝克也都对其作品产生了深远影响。文章还进一步解读了巴拉甘的景观设计语言，分析了色彩、墙体、水面、光线、马等应用元素。最后阐明了巴拉甘作品对当今中国景观设计的影响和启示。