Estimation of genetic variance components and heritabilities for cut-flower yield in gerbera using least squares and maximum likelihood methods

Summary Genetic variance components and heritability were estimated for cut-flower yield of gerbera in the Davis population using ordinary least squares and maximum likelihood methods. The overall estimate of narrow-sense heritability is 0.33 based on least squares (LS) and 0.31 based on maximum likelihood (ML). The results of the study indicate that (1) ML and LS provide very similar results if sample size is large enough, suggesting both are useful for plant breeding programs; (2) about one third of the variation in gerbera cut-flower yield is additive, implying selection in cut-flower will be successful; and (3) although additive variation gradually decreased, heritability remained near 0.27 suggesting there is still potential variation in the population for further selection.     

外源水杨酸对盐胁迫下非洲菊抗氧化酶活性和生理特性的影响(英文)

以非洲菊(Gerbera jamesonii L.)品种Amaretto'为试材,研究外源水杨酸(SA)对缓解非洲菊生殖生长期因盐胁迫引起的过氧化伤害作用.在开花前分别用0、0.5和1.0mmol L-1SA对非洲菊植株进行预处理,3d后用100mmol L-1NaCl灌溉,持续2周;对照植株未经NaCl和SA处理.结果表明:盐胁迫处理后,叶片的超氧化物歧化酶(SOD)和过氧化物酶(POD)活性增加,丙二醛(MDA)含量、电解质外渗率和脯氨酸含量提高;外源SA预处理显著降低了盐胁迫植株叶片的MDA含量和电解质外渗率;在外源0.5mmol L-1SA预处理后,植株SOD和POD活性分别是对照的1.4倍和2.4倍;SA预处理后与植株耐盐性相关的生理生化指标呈显著相关,以0.5mmol L-1SA处理增强植株盐胁迫耐性的效果更好.说明外源SA处理能够诱导盐胁迫下非洲菊植株的抗氧化反应,水杨酸将是一种提高园艺作物耐盐性的有效物质.     

Methods for selecting flower quality based on consumer evaluation

Summary The quality ranking of a sample of Gerbera cut-flowers varies greatly from one person to another. Further, there are significant differences between the rankings assigned by a panel of trained horticulturalists and a panel sampled from the general public. Therefore, the selection of a panel to evaluate the flower quality component of a breeding program is very important to the outcome. If the purpose of a program is to breed (those) flowers preferred by the general public then the selection of flowers should be done by a panel sampled from the general public. The prediction of consumer preferences by multiple linear regression techniques using eleven flower characters was not successful. Much greater predictive value was obtained by measuring the perceived information content of flowers. This indicates that flower characteristics which increase flower complexity may be preferred. Implications to the practical breeding program are discussed.     

非洲菊过氧化物酶同工酶酶谱分析

分别以 6个品种非洲菊的成熟叶片和中心筒状花为试材 ,采用垂直平板聚丙烯凝胶电泳对其中的过氧化物酶同工酶进行分析。结果发现 ,该方法能够清楚地显示各品种间亲缘关系的远近 ;而且证明 ,中心筒状花不适于进行过氧化物酶同工酶分析。根据电泳显示的各品种条带分布 ,大致勾勒出功能叶片的酶谱类型。非洲菊的外部形态特征与同工酶鉴定结果在某些品种上存在差异 ,可能是环境因素的作用     

Paraquat Resistance in Leaf Discs of PAAG12-IPTModified Gerbera Is Related to the Activities of Superoxide Dismutase, Catalase, and Dehydroascorbate Reductase

In this paper, using in vitro leaf disc culture system, the changes of contents of chlorophylls, carotenoids, soluble protein, thiobarbituric acid reactive substance （TBARS）, and activities of antioxidant enzymes were investigated during the incubation of leaf discs of PSAG12-IPT modified gerbera in 0, 25, 50 μmol L^-1 paraquat （PQ） under continuous light intensity of 130 0tool m-2 s-1, compared with the control plant （wild type）. The results showed that PQ treatment significantly decreased the contents of chlorophylls, carotenoids, and soluble protein, therefore, promoted leaf senescence. However, the decreases in the leaf discs of modified gerbera were considerably smaller. The activities of superoxide dismutase （SOD）, catalase （CAT）, and dehydroascorbate reductase （DHAR） were significantly increased by PQ treatment and with the increasing of PQ concentration, particularly in the modified plants. The activities of ascorbate peroxidase （APX） and guaiacol peroxidase （GPX） could not be detected in the leaf discs of PQ treatments, which suggested that they were labile to the oxidative stress induced by PQ. As a product of lipid peroxidation, TBARS significantly increased in content with the increase of PQ concentration, while its concentration in the modified plants was significantly lower than that of control plants. Therefore, it could be concluded that the chimeric gene PSAG12-IPTtransfonnexi gerbera leaves had higher antioxidative potential, thus causing the delay of senescence under oxidative stress induced by PQ.     

非洲菊切花弯茎影响因素研究进展

非洲菊（Gerbera jamesonii）切花采后易出现弯茎现象,造成瓶插寿命缩短,观赏价值下降。非洲菊弯茎的发生受到其内在因素和外界环境的综合调控。从非洲菊花茎组织结构、物质代谢、导管堵塞、植物激素等方面对弯茎影响因素进行了综述,并在此基础上对进一步探讨弯茎影响因素之间的联系及其分子调控机制提出了展望。     

抗生素对非洲菊试管苗不定芽分化的影响研究

以卡那霉素和潮霉素作为非洲菊抗性植株的选择剂,头孢霉素和羧苄青霉素为抑菌剂,分别采取不同浓度,分析其对非洲菊试管苗不定芽分化的影响.结果表明,25 mg·L-1的卡那霉素或5 mg·L-1的潮霉素可作为非洲菊抗性植株的临界筛选浓度.头孢霉素浓度愈大,213品种不定芽分化频率愈低,当头孢霉素浓度较高(400～500 mg·L-1)时,愈伤组织生长受到抑制;而羧苄青霉素对愈伤组织影响很小,在适宜的浓度下能促进不定芽分化,213品种在羧苄青霉素浓度为200 mg·L-1时,分化频率达到最大值68.8.     

外源NO对非洲菊切花保鲜效果及作用机制

以硝普钠(SNP)作为外源NO的供体,分别采用0,10,100,500μmol·L-1浓度的SNP溶液作为非洲菊‘阳光海岸’的瓶插液,观察NO对非洲菊鲜切花的保鲜效果.同时,测定了花瓣超氧化物歧化酶(SOD),过氧化物酶(POD)、过氧化氧酶(CAT)活性的变化以及H2O2、丙二醛(MDA)、可溶性蛋白含量的变化.结果显示,100μmol·L-1浓度处理的非洲菊切花瓶插寿命最长,比对照延长了31.4％;外源NO提高了花瓣SOD,POD,CAT等保护酶的活性,也提高了可溶性蛋白质的含量,而H2O2,MDA含量比对照降低,从而延缓了非洲菊切花花瓣的衰老.     

Heritability of inflorescence and floret traits in gerbera

Summary Heritability, repeatability, and components of variance were estimated for 68 morphological characters describing the inflorescence, scape, and florets of Gerbera hybrida. The heritability estimates were generally moderate to high for simple dimension characters and characters which were the mean of several measurements, low to moderate for ratio and composite characters, and low for enumeration characters and characters describing the intraplant variation of traits. The repeatability estimates were generally low for intraplant variation characters, moderate for simple ratio characters, and largest for composite and mean characters. For most of the characters, the variance among inflorescences from the same plant was the largest portion of the total phenotypic variance.     

Components of genetic variation for cut-flower yield in the Davis Population of Gerbera

Summary Genetic variances for cut-flower yield in Gerbera hybrida were partitioned into additive and dominance components. Mean additive variance was 37.3 with a standard error of 12.9. Mean dominance variance was 12.7 with a standard error of 32.6. The dominance ratio was 0.34. Narrow sense heritability, estimated from these components of variance, averaged 0.42 with a standard error of 0.13. Heritabilities estimated from parent-offspring regression averaged 0.25. Gain from selection was less then expected; realized heritabilities were approximately 0.20.