白光下光敏素对番茄幼苗胚轴长度、花青素含量及开花的控制

 以番茄野生型（WT）和光敏素突变体phyA、phyB1、phyB2、phyB1phyB2和phyAphyB1phyB2为材料，研究了光敏素PHYA、PHYB1和PHYB2对番茄幼苗胚轴生长、花青素含量以及植株开花时间的影响。结果表明，白光下光敏素PHYA、PHYB1和PHYB2对番茄幼苗胚轴伸长和花青素合成的影响不同。PHYB1对胚轴伸长具有明显的抑制作用，同时促进花青素的合成。PHYA和PHYB2对胚轴伸长和花青素合成的影响程度较小，但是与PHYB1具有明显的互作效应。双突变体phyB1phyB2的首花节位和开花时间明显提前，三突变体phyAphyB1phyB2的第1～4 花序生长早期即停滞，花序极其微小。     

小麦品种豫麦66的散粉特性和穗部特征研究

以豫麦49、豫麦18为对照,对豫麦66及其优系和矮早系的花器构造、散粉特性和穗部特征进行了研究。结果表明:与对照相比,豫麦66各系的花药大,穗子较长,开颖角度较大,开花持续期较长,而且穗粒数、穗花数、外露花药数、中部穗粒数都较多,是理想的杂交小麦父本材料。     

摘花序、打顶对商洛丹参生长的影响

[目的]考察摘花序、打顶对商洛丹参生长的影响。[方法]对种植于陕西商洛香菊药源基地的2年生丹参样品,采用摘花序、打顶的处理方法,研究其对丹参生长性状及根部有效成分的影响。[结果]摘花序、打顶后的植株生长健壮、干物质积累多、根部产量高、有效成分积累量大,处理结果明显优于2种处理方法单独使用的效果。[结论]试验考察了摘花序、打顶对商洛丹参生长的影响,为商洛丹参的种质资源栽培提供了理论依据。     

蓖麻花序分化发育的解剖观察

对蓖麻不同熟性类型品种的主花序分化发育过程以及主花序分化与分枝发育间的关系作了解剖分析。将蓖麻花序分化过程划分为生长锥伸长膨大、花梗分化、小花分化、花粉粒和子房形成、花粉粒充实完成等五个时期。描述了各期解剖形态特征,划定了持续时段。提出把叶余数作为花序分化发育进程的间接标准用于生产实践。     

Effect of exogenous application of free polyamines on physiological disorders and yield of ‘Kaleh-Ghoochi’ pistachio shoots (Pistacia vera L.)

Pistachio trees exhibit some physiological disorders such as abscission of inflorescence buds, fruit abscission, the production of blank, non-split, early-split and deformed nuts. Since the occurrence of these disorders is closely related to the yield, the effect of free polyamine treatments on these disorders and the yield was investigated in two consecutive years (“on” and “off” years). Free polyamine treatments were applied one week before and also two weeks after full bloom. Results showed that Spermine (Spm), unlike Putrescine (Put), decreased the physiological disorders of pistachio and also increased the yield. Free polyamine treatments did not affect the percentage of early-split nuts. Spermidine (Spd) decreased the percentage of both fruit abscission and deformed nuts but did not affect the yield. In both the “on” and “off” years the effect of Spm and Spd was greatly dependent on both the time of application and the concentrations used. Results of free polyamine analysis showed that exogenous application of these compounds, especially two weeks after full bloom, increased the free polyamine contents of shoots in both “on” and “off” years confirming the absorption of free polyamines via spray application in pistachio crop. Exogenous application of Spm two weeks after full bloom decreased the abscission of inflorescence buds in “on” year supporting the idea that free polyamines could trigger the abscission process of inflorescence buds. Since Spm decreased the percentage of blank, non-split and deformed nuts, it seems that Spm dominantly plays a key role in the growth and development of pistachio nuts.     

Effect of photoperiod and temperature on inflorescence appearance and subsequent development towards flowering in onion raised from sets

The plants of two onion cultivars Sturon and Stuttgarter were raised from sets and placed in a growth room at 12 °C, a light flux density of 120 μmol m⁻² s⁻¹ and a 16 h photoperiod. Cultivar Stuttgarter took 195 days to initiate, whereas time for initiation in cv. Sturon was 201 days. After initiation the plants were transferred to wide range of photo-thermal regimes consisting of six set point temperatures (6, 10, 14, 18, 22 and 26 °C) and four photoperiods (8, 11, 14 and 17 h day⁻¹). An overall mean temperature for all developmental stages under each photo thermal combination was 12.2, 12.4, 15.9, 17.8, 23 and 24.4 °C. Time to inflorescence appearance, spathe opening and floret opening decreased linearly as temperature and photoperiod increased. At low to mild temperatures (12.2–17.8 °C), longer photoperiod enhanced florets per umbel, whereas at higher temperatures (23–24.4 °C), the floret number declined with lengthening photoperiods. As the photoperiod extension in each temperature advanced inflorescence appearance, spathe opening and floret opening and this would be beneficial in a programme to accelerate seed production in onion.     

冬季期间温度和水分对暗柳橙成花和花序类型的影响

冬季期间通过人工调控气温和土壤水分研究高温(30/25℃)、低温(冬季自然温)、高温(80％～90％F、C)和干旱(40％～50％F、C)对甜橙成花的单独与交互作用。低温或干早都能单独地诱导暗柳橙成花,但干旱因子在促花的同时有减弱叶片形成的效应,而低温因子主要表现为促进花的数目。高温加高湿导致不停顿的营养生长和不成花。足够的低温和适度的干旱有利于形成有叶花枝,因而有利于翌年之丰产,过度干旱导致形成无叶花枝,恶化花枝质量。     

燕麦新品种燕科一号组织培养特性及再生体系研究

为建立燕麦遗传转化的高效植株再生体系,选用裸燕麦新品种燕科一号的幼穗进行组织培养特性和再生体系研究。结果表明,在6种诱导培养基上愈伤组织状态和诱导率差异不大;在进一步继代培养过程中愈伤组织出现明显差异,其中培养基Y2和J结合培养效果好;愈伤组织分化产生绿色芽点和绿苗,二者分化率呈显著正相关;绿苗分化适宜的激素配比是6-BA0．5mg／L＋KT0．4mg／L＋NAA0．4mg／L,有84．90％的愈伤组织分化成苗,其中KT的作用较6-BA、NAA强;在1／2MS培养基上再生苗容易生根,生根率达到89．64％,移栽成活率91．05％;幼穗取样以0．5～1．0cm最为理想。     

一种新型的大蒜快繁体系-花苞不定芽再生体系的建立

大蒜花苞具有很强的不定芽增生潜力,是不定芽体系快繁的理想外植体。在MS NAA1 mg/L KT5 mg/L培养基上,早苔2号蒜花苞的繁殖系数为19.2,晚熟品种的繁殖系数更高。低温能促进试管鳞茎的发生,花苞4℃预处理10d后,82.9%的不定芽都形成试管鳞茎。由大蒜花苞诱导不定芽的发生,然后诱导试管鳞茎的形成,这是一种适于大蒜快繁的新型再生体系。