银耳‘Tr2016’的选育报告

银耳‘Tr2016’是由福建省尤溪县枕头山的枯木上发现的一株野生银耳,进行反复多次分离和多年驯化而来。银耳菌丝具锁状联合,可形成白色或淡黄白色菌落;子实体呈雪白色,由多片波浪状卷曲的耳片组成牡丹花状,烘干后为淡黄色。栽培周期从接种到采收约45d,鲜耳平均直径13.2cm,高度7.2cm,平均产量为114.0g/瓶,干耳平均产量34.1g/瓶。     

不同辣椒品种抗（耐）西花蓟马的初步筛选及苗期防御酶的变化

【背景】西花蓟马自2003年传入我国以来,呈扩张趋势。辣椒上西花蓟马以化学防治为主,国内尚无抗性资源保护、抗（耐）虫性资源筛选等相关研究。【方法】以20个辣椒品种和西花蓟马为材料,采用幼苗接虫法,根据危害症状分级,计算为害指数并作为抗（耐）评价指标,然后测定不同抗（耐）材料苗期受西花蓟马危害后防御酶活性的变化,探讨其与抗性的关系。【结果】在20个供试辣椒品种中,湘研13号和博辣4号对西花蓟马的抗性较强,其他品种抗性较差,兴蔬绿剑抗性最差;不同辣椒品种抗（耐）虫性与过氧化物酶变化呈正相关,但与过氧化氢酶相关性不显著。【结论与意义】本研究建立了辣椒抗（耐）西花蓟马的筛选评价体系,为挖掘抗西花蓟马的种质资源和西花蓟马的有效防控提供了依据。     

基于叶形特征的切花菊品种鉴别

通过测定、计算获得40个切花菊品种叶片的6个定性分级性状及叶片的长宽比、尖削度、裂片长宽比、裂片开张度等14个叶形结构参数。以6个定性分级性状为变量,用聚类法选取叶形相似性大的18个切花菊品种,通过多元判别分析法对18个品种叶片的形态结构参数进行数值化鉴别。结果表明,18个叶形相似的品种多元判别的平均拟合率为88．28％,达到了判别品种的目的。说明根据叶形的测量数据能对切花菊品种进行有效鉴别。     

Seedling root response of some Kenyan bread wheat cultivars grown in acid nutrient culture solution containing aluminum

The objective of this study was to determine whether a series of Kenyan bread wheat cultivars differed in tolerance to aluminum toxicity. Fourteen Kenyan wheat cultivars representing current and former widely grown cultivars of diverse pedigree origin, and two control cultivars, Maringa (Al-tolerant) and Siete Cerros (Al-susceptible), were tested in solution cultures with 0 (control), 148, 593, and 2370 M Al at pH 4.6. Highly significant (p0.01) differences in seedling growth were observed among cultivars for root mass, root length and root tolerance index (RTI). Significant (p0.05) cultivar × treatment interactions were observed for root mass and RTI. All characters were negatively affected by increased Al concentration, with root length and root mass being affected the most. RTI is a commonly used index which measures the relative performance of individual cultivars with and without aluminum stress. High levels of tolerance to Al were identified in the Kenyan cultivars by evaluating RTI with this simple nutrient solution technique. Romany and Kenya Nyumbu had RTI values approaching those of the Al tolerant Brazilian cultivar Maringa, a spring wheat standard that has been used for high Al tolerance.     

Variation in acquisition of soil phosphorus among wheat and barley genotypes

To assess the extent of variation in phosphorus acquisition efficiency of some winter wheat (Triticum aestivum L.), winter and spring barley (Hordeum vulgare L.) genotypes, depletion of inorganic phosphorus (P) extractable with 0.5 M NaHCO₃ (NaHCO₃-P_i) from the rhizosphere soil was studied. Nutrients supply, rhizosphere soil pH and soil water content was kept equal for all the genotypes with the aim to reduce the confounding variation due to these factors. The experimental set up implied that no difference in the relative growth rates, nitrogen, potassium and calcium content of shoot dry matter occurred among the genotypes.The winter wheat, winter barley and spring barley genotypes differed significantly (p>0.05) in their efficiency to acquire NaHCO₃-P_i from the rhizosphere soil. The efficiency of the winter wheat genotypes to acquire NaHCO₃-P_i from rhizosphere soil ranked Kraka > Gawain > Foreman > Sleipner = Obelisk > Kosack > Pepital > Arum. Winter wheat genotypes differed in extent of P depletion profiles in the rhizosphere, indicating variation in root hair length. The winter barley and spring barley genotypes also showed significant differences in their P depletion profiles near roots. The efficiency of the winter barley genotypes to acquire soil P in the rhizosphere ranked Hamu > Frost > Marinka > Astrid > Clarine = Angora. The efficiency of spring barley genotypes to acquire NaHCO₃-P_i in the rhizosphere ranked Canut > Etna Riga > Digger > Peel > Semal > Alexis. The rhizosphere pH remained unchanged, suggesting that additional mechanisms such as root hair formation and root exudates play a significant role in causing variation in P acquisition among the genotypes.     

Effect of specific leaf nitrogen content on photosynthesis of sugarcane

In the laboratory, rate of photosynthesis (P) of the youngest fully emerged leaf lamina on a shoot, whether taken from a 4 or 8 month old sugarcane plant, increased approximately linearly with specific leaf nitrogen content (SLN) from < 1.0 to c. 1.7 g m^-2; the rate of increase was greater the higher the incident photosynthetically active radiation (PAR) flux density, over the range 80 to 1600 μmol m^-2s^-1. In a field crop receiving standard fertiliser, including 150 kg N ha^-1, SLN of the green leaf canopy decreased more or less linearly with depth, from > 1.7 g m^-2at the top to c. 1.0 g m^-2at the bottom at 15 wk of age, and progressively with time to 1.2 to 0.85 g m^-2from top to bottom of the canopy by week 45. Where an extra 300 N ha^-1were applied in top-dressings, the decrease in SLN with time was somewhat smaller, to 1.3 to 0.9 g m^-2from top to bottom of the canopy by week 45. Calculations with a model, using the data from laboratory and field, suggest a decrease of about 25% in canopy gross P and about 30% in canopy net P from wk 15 to wk 45 in the crop receiving standard fertiliser only; the calculated decreases where the crop received additional nitrogen were about 17% and 20% respectively. There would seem to be a need for a change in type of cultivar to make profitable use of augmented nitrogen fertiliser.     

Phenolic compounds (hydroxycinnamic acids,flavan-3-ols,flavonols) profile in fruit of Italian peach varieties

Interest in phenolic compounds of fruit is growing due to their positive effects on reducing the risk of cardiovascular and carcinogen diseases. The role of the flesh colour, of the tissue (exocarp or mesocarp) and of the cultivar on the content of phenolic compounds (hydroxycinnamic acids, flavan-3-ols, flavonols) was evaluated in peach, Prunus persica (L.) Batsch, with a HPLC-DAD analysis, on 10 varieties deriving from the Italian breeding programmes, never previously characterized by this approach. The flavan-3-ols (catechin, epicatechin and procyanidin B1) were the most abundant class of phenolic compounds in peach cultivars analysed. Among hydroxycinnamic acids, neochlorogenic and chlorogenic acids were also identified and measured in the peach cultivars analysed. Quercetin-3-O-rutinoside was the only flavonol found in the exocarp of all the cultivars evaluated, but in the mesocarp of only some cultivars. Content of phenolic compounds was confirmed to be strongly dependent on the cultivar and, in general, the content was significantly higher in exocarp than in mesocarp. An overall significant difference in phenolic compounds as associated with flesh colour was not observed.     

Translocation and nuclear accumulation of monomer and dimer of HIV-1 Tat basic domain in triticale mesophyll protoplasts

Cellular internalization of cell-penetrating peptide HIV-1 Tat basic domain (RKKRRQRRR) was studied in Triticale cv AC Alta mesophyll protoplasts. Fluorescently labeled monomer (Tat) and dimer (Tat₂) of Tat basic domain efficiently translocated through the plasma membrane of mesophyll protoplast and showed distinct nuclear accumulation within 10 min of incubation. Substitution of first arginine residue with alanine in Tat basic domain (M-Tat) severely reduced cellular uptake of the peptide (3.8 times less than Tat). Tat₂ showed greater cellular internalization than Tat (1.6 times higher). However, characteristics of cellular uptake remained same for Tat and Tat₂. Cellular internalization of Tat and Tat₂ was concentration dependent and non-saturable whereas no significant change in cellular uptake was observed even at higher concentrations of M-Tat. Low temperature (4 °C) remarkably increased cellular internalization of Tat as well as Tat₂ but M-Tat showed no enhanced uptake. Viability test showed that peptide treatment had no cytotoxic effect on protoplasts further indicating involvement of a common mechanism of peptide uptake at all the temperatures. Endocytic inhibitors nocodazole (10 μM), chloroquine (100 μM) and sodium azide (5 mM) did not show any significant inhibitory effect on cellular internalization of either Tat or Tat₂. These results along with stimulated cellular uptake at low temperature indicate that Tat peptide is internalized in the plant protoplasts in a non-endocytic and energy-independent manner. Competition experiments showed that non-labeled peptide did not inhibit or alter nuclear accumulation of fluorescent Tat or Tat₂ suggesting active transport to the nucleus was not involved. Studies in mesophyll protoplasts show that internalization pattern of Tat peptide is apparently similar to that observed in mammalian cell lines.     

不同白化期的‘黄山白茶’代谢物差异分析

‘黄山白茶1号’是温度敏感型白化茶树品种,由其鲜叶加工的绿茶,即‘黄山白茶’,具有清香持久、滋味鲜爽等特征。为探究不同白化时期加工绿茶的香气和滋味差异,分析了绿茶中挥发性代谢物、儿茶素、咖啡碱和游离氨基酸含量的变化。结果表明,3个白化时期的‘黄山白茶’在香气和滋味上存在差异。气相质谱（GC-MS）分析表明,共有29个高丰度挥发性化合物被鉴定;主成分分析（PCA）显示芳樟醇、顺-己酸-3-己烯酯、香叶醇、顺-3-己烯醇、（Z）-丁酸-3-己烯酯可能是导致3类绿茶香气存在差异的标志性化合物。滋味成分分析表明儿茶素类物质在白化早期绿茶中含量最低;在白化中期绿茶中略有增加但不显著,而在白化后期绿茶中则显著增加;咖啡碱在3类绿茶中无显著差异;游离氨基酸在白化早期绿茶中含量最高,为干质量的4.4%,而在白化后期绿茶中只占干质量的1.3%。因此,不同时期的‘黄山白茶1号’嫩梢中的代谢物积累存在差异,使得加工的绿茶风味不同。     

Biochar coupling with phosphorus fertilization modifies antioxidant activity,osmolyte accumulation and reactive oxygen species synthesis in the leaves and xylem sap of rice cultivars under high-temperature stress

Increasing temperature poses a serious threat to rice productivity. This study investigated the impact of various biochar treatments and phosphorous (P) fertilization on osmolyte accumulation, ROS development, and antioxidant activity in two rice cultivars (IR-64 and Huanghuazhan) under high-temperature stress. All plants of both cultivars were grown in a controlled environment under ambient temperatures (AT), high day temperatures (HDT) or high night temperatures (HNT). The different fertilization treatments were biochar alone, P alone and biochar + P with control. In the leaves and xylem sap of both rice cultivars, particularly in the susceptible cv. IR-64, high-temperature stress increased the production of MDA and H₂O₂. HDT and HNT decreased total soluble sugars, protein, and proline levels in both rice cultivars. HNT was observed as more harmful compared to HDT during most of the studied characteristics. The response of antioxidant enzyme activities, viz, SOD, POD, CAT, APX, ASC, GSH, GR, and GSSC activities, to the temperature treatments varied between the two cultivars. Antioxidant activities decreased in the leaves and xylem sap of IR-64 but increased in those of Huanghuazhan upon exposure to high-temperature stress. Huanghuazhan exhibited better heat tolerance compared to IR-64, which was linked to its increased antioxidant enzyme activation and metabolite synthesis. As compared to the control, all soil fertilization treatments considerably reduced the adverse impacts of high temperature on the rice cultivars. The combination of biochar and P resulted in better performance compared to the other treatments in terms of all studied attributes.