Effect of Temperature,pH, and Media on the Mycelial Growth of Tuber koreanum

Members of the genus Tuber are ectomycorrhizal fungi; this genus includes more than 180 species worldwide. In the present study, the optimal pH, temperature, and medium suitable for the mycelial growth of the Korean truffle, Tuber koreanum, were determined. Mycelium of T. koreanum, isolated from fruiting bodies collected in Korea, was used to investigate the effects of these environmental factors. The results showed that malt extract agar and potato dextrose agar were the most suitable for the mycelial growth of T. koreanum when cultured at a pH of 6.0 at 25 °C for 30 days.     

Influence of Temperature and Light Conditions on Germination,Growth and Conidiation of Oidium neolycopersici

The effect of temperature and light conditions (spectral quality, intensity and photoperiod) on germination, development and conidiation of tomato powdery mildew (Oidium neolycopersici) on the highly susceptible tomato cv. Amateur were studied. Conidia germinated across the whole range of tested temperatures (10–35°C); however, at the end‐point temperatures, germination was strongly limited. At temperatures slightly lower than optimum (20–25°C), mycelial development and time of appearance of the first conidiophores was delayed. Conidiation occurred within the range of 15–25°C, however was most intense between 20–25°C. Pathogen development was also markedly influenced by the light conditions. Conidiation and mycelium development was greatest at light intensities of approximately 60 μmol/m² per second. At lower intensities, pathogen development was delayed, and in the dark, conidiation was completely inhibited. A dark period of 24 h after inoculation had no stimulatory effect on later mycelium development. However, 12 h of light after inoculation, followed by continuous dark, resulted in delayed mycelium development and total restriction of pathogen conidiation (evaluated 8 days postinoculation). When a longer dark period (4 days) was followed by normal photoperiod (12 h/12 h light/dark), mycelium development accelerated and the pathogen sporulated normally. When only inoculated leaf was covered with aluminium foil while whole plant was placed in photoperiod 12 h/12 h, the intensive mycelium development and slight subsequent sporulation on covered leaf was recorded.     

Ca2+、pH在花粉及萌发花粉管生长中的作用研究进展

花粉正常萌发并生长是精细胞顺利到达胚囊并实现受精作用的前提,因而是高等植物有性生殖的一个关键环节。花粉管生长涉及一系列过程,而花粉(或花粉管)内外的Ca^2 和pH的变化与花粉萌发、花粉管生长有着密切的关系。比较详细地论述了Ca^2 和pH在花粉萌发、花粉管生长过程中的分布特点、生理功能及分子机制。     

培养基组分及pH值对梨花粉萌发和花粉管生长的影响

采用花粉液体培养法研究不同培养基组分和pH值对梨花粉萌发和花粉管生长影响.结果表明:培养基内硼酸、氯化钙、PEG-4000、蔗糖、葡萄糖、麦芽糖、山梨醇、果糖在一定浓度范围内,对花粉萌发及花粉管生长起促进作用,但超过一定浓度时起抑制作用;最适的培养基组分为:30mmol/LMES、0.01%硼酸、0.03%CaCl2·2H2O、15%PEG-4000、5%果糖 或5%山梨醇、10%蔗糖 ,最适的pH值为6.5.在该培养基内梨花粉萌发率约为59.2%,花粉管生长长度为966.3μm.     

光照、温度和盐分对梭梭种子萌发的影响

梭梭是我国西北荒漠中分布的多年生植物,属中亚荒漠植被成分。其种子萌发的最适温度为10℃,亚适宜温度为15～20℃。从20℃起,温度越高,萌发比率越低。种子无论在光下和暗中都能萌发,萌发率无显著性差异。浓度低于0.2mol/L的NaCl溶液对萌发的影响不大;但从0.8mol/L起,萌发率随着浓度增高而降低,直至为零。将在盐溶液中处理9d的种子转移至蒸馏水后,原来较高浓度下的种子具有较高的萌发恢复率。不同浓度下的种子的萌发率和萌发恢复率要比蒸馏水中的低,表明NaCl处理后的部分种子永久地失去萌发力。     

光照、温度和盐分对长叶红沙种子萌发的影响

无论在光下和暗中长叶红沙种子都能萌发,萌发率无显著差异;种子萌发的适宜温度为20~25℃。温度高于25℃时,温度越高,萌发率越低;浓度低于100mmol·L-1的NaCl对种子萌发的影响不大,但高于150mmol·L-1时,NaCl下的萌发率随着NaCl浓度的增高而下降,直至0;NaCl溶液处理9d的未萌发种子转移至蒸馏水中后,经高浓度NaCl胁迫(小于500mmol·L-1)处理的种子萌发恢复率较高。     

Ca2+对韭兰花粉萌发和花粉管生长的影响

采用离体花粉培养技术,研究不同浓度Ca²⁺对韭兰花粉萌发和花粉管生长的影响。结果表明,较低浓度(10^-3 mol/L)的Ca²⁺对花粉萌发具明显地促进作用,并促进花粉管较快伸长;而过高或过低浓度则起不到促进的作用。     

钙和硼对蓝猪耳花粉萌发及花粉管生长的影响

研究了钙(Ca^2 )和硼(H3BO3)对蓝猪耳花粉萌发和花粉管生长的影响。结果表明：(1)在一定范围内Ca^2 几乎不影响花粉萌发频率,而主要影响花粉萌发速度和花粉管生长速度;低Ca^2 不利于花粉管生长,而高Ca^2 抑制花粉萌发速度和花粉管生长;在稍高于最适Ca^2 浓度的条件下,花粉管生长早期呈现波浪形。(2)硼明显影响花粉萌发频率及花粉管形态;花粉管生长必需硼,但不同浓度的硼对花粉管生长速度影响不明显;在高浓度硼条件下,较长时间内花粉管均呈现出波浪形。(3)Cooled-CCD动态跟踪观察进一步证实Ca^2 影响花粉管生长速度,而硼则不明显。     

西南獐芽菜种子萌发对温度、光照和外源生长调节物质的响应

研究不同温度、光照和外源生长调节物质处理种子对西南獐芽菜种子萌发特性的结果表明,西南獐芽菜种子为休眠型种子,其最适合萌发温度为20℃。光照促进种子的萌发,但影响并不显著。低浓度（10mg·L-1）6-BA促进西南獐芽菜种子萌发,而高浓度（50mg·L-1）的则抑制其萌发,不同浓度和浸种时间的赤霉素（GA）和IAA均促进种子萌发,GA的效果更好。     

不同贮藏温度对彩色马蹄莲块茎内源激素变化及萌芽与生长的影响

以彩色马蹄莲（Zantedeschia hybrids）的‘Black Magic’为试材,研究其块茎经不同贮藏温度和时间处理后,块茎内源激素的变化及对块茎萌芽的影响。结果表明：在不同温度条件下,随贮藏时间的延长,GA,和IAA含量水平均呈上升的趋势,并且贮藏温度越高,GA,含量水平越高。脱落酸ABA含量与GA3呈相反的变化趋势,相同贮藏天数均为15℃处理ABA含量水平最低,6℃处理ABA含量水平最高。随着贮藏时间延长,GA3／ABA、IAA／ABA质量分数比值越大。GA3／ABA、IAA／ABA质量分数比值与块茎萌芽率之间存在一定程度的对应关系。     

高温对苹果花粉在花柱内萌发和生长的影响

以‘长富2号’红富士苹果为母本,‘红星’苹果为父本,研究35℃高温对苹果花粉在花柱内萌发和生长的影响。结果表明：温度影响花粉在柱头和花柱内的萌发及生长,与对照相比,高温促进花粉在柱头表面快速萌发,并加速花粉管在花柱内的伸长生长,但是在授粉72hN,高温处理下培养的花粉管形态出现花粉管变粗、弯曲并有瘤状小结的异化现象,同时,花柱发生褐变,并产生胼胝质,最终导致花粉管不能进入胚珠完成受精。     

光照、温度和土壤水分对孜然芹种子萌发和幼苗生长的影响

连续光照和连续黑暗条件下,孜然芹种子萌发最适宜温度为25℃;16h光照18h黑暗的条件下,萌发最适温度为20℃和25/16℃的日夜变温。种子萌发最适宜土壤含水量为15％。     

花柱和花粉胞外钙调素对花粉萌发和花粉管伸长的影响

以烟草为材料,通过半体内实验,就花柱和花粉胞外钙调素对花粉萌发和花粉管伸长的影响进行了观察。发现用EGTA及钙调素抗血清处理柱头或花粉均可抑制花粉在柱头上的萌发;向花柱引导组织中显微注射纯化钙调素可促进花粉管束伸长,而注射钙调素抗血清可抑制花粉管束伸长;同时证实玉米花柱和花粉细胞壁中均存在钙调素及钙调素结合蛋白,而且花粉和花柱细胞壁中钙调素结合蛋白的种类有差异。结果表明存在于花粉和花柱细胞外的钙调素对花粉萌发和花粉管伸长均有促进作用。     

不同pH值土壤及其浸提液对羊草种子萌发和幼苗生长的影响

研究了不同pH值土壤以及重度盐碱土和非盐碱土浸提液对羊草(Leymus chinensis)种子萌发及幼苗生长的影响。不同pH值土壤由配土和调酸两种方式取得,前者由重度盐碱土(pH=10．24)与非盐碱土(pH=7．49)按不同比例配制,后者是由重度苏打盐碱土经硫酸调酸处理得到。配土发芽的实验结果表明,当pH值在7．49-9．14时,种子的发芽率均在50％以上,且幼苗能够正常生长;pH=9．53时,羊草种子的发芽率低于50％,仅部分幼苗个体能够成活;当pH>9．86时,幼苗在萌发后50天左右全部枯死。说明羊草种子个体萌发期最大耐受pH值在9．14-9．53之间。重度苏打盐碱土调酸发芽实验结果表明,当调酸后的土壤pH值降至7．0-10．0时,均能显著促进羊草种子的萌发,且幼苗生长正常。确定了羊草种子萌发的最适pH值为8．0-8．5。土／水比为1:1的非盐碱土浸提液能够显著提高羊草种子发芽率,而重度苏打盐碱土浸提液对羊草种子萌发没有产生显著抑制。     

光照和温度对望天树种子萌发的影响

在实验室内人工气候箱控制的条件下,研究了我国重要珍稀濒危植物望天树（Shorea wantianshuea,龙脑香科（Dipterocarpaceae））种子萌发对持续光照、14小时光照／10小时黑暗周期性光照的反应;同时研究了望天树种子的萌发对不同温度的反应和低温贮藏对种子活力的影响。结果表明,不论是持续光照还是周期性光照都不能提高望天树种子的萌发率,相反,持续光照和周期性光照都不同程度降低了种子萌发率。光照能通过加速或延迟种子萌发的进程、或改变幼苗活力指数和萌发指数而影响种子萌发的质量;持续光照延迟种子萌发的进程,而周期性光照加快种子萌发的进程。30℃是种子的最适萌发温度,虽然15℃和5℃的相对低温对幼苗活力指数影响不大,但大大延迟了种子萌发进程,并提高萌发率。望天树种子不能耐受5℃低温贮藏,但具有在15℃下短期贮藏的潜力和一定程度的生理性休眠。     

The Influence of Water Activity and Temperature on Germination,Growth and Sporulation of <Emphasis Type="Italic">Stachybotrys chartarum</Emphasis> Strains

The objectives were to determine the influence of water activity (a_w, 0.997–0.92) and temperature (10–37°C) and their interactions on conidial germination, mycelial growth and sporulation of two strains of Stachybotrys chartarum in vitro on a potato dextrose medium. Studies were carried out by modifying the medium with glycerol and either spread plating with conidia to evaluate germination and germ tube extension or centrally inoculating treatment media for measuring mycelial growth rates and harvesting whole colonies for determining sporulation. Overall, germination of conidia was significantly influenced by a_w and temperature and was fastest at 0.997–0.98 a_w between 15 and 30°C with complete germination within 24 h. Germ tube extension was found to be most rapid at similar a_w levels and 25–30°C. Mycelial growth rates of both strains were optimal at 0.997 a_w between 25 and 30°C, with very little growth at 37°C. Sporulation was optimum at 30°C at 0.997 a_w. However, under drier conditions, this was optimum at 25°C. This shows that there are differences in the ranges of a_w x temperature for germination and growth and for sporulation. This may help in understanding the role of this fungal species in damp buildings and conditions under which immune-compromised patients may be at risk when exposed to such contaminants in the indoor air environment.     

温度、蔗糖和硼酸对含笑花粉离体萌发的影响

以含笑(Michelia figo)花粉为试验材料,采用花粉人工培养法研究了含笑花粉离体萌发的最适条件。结果表明:蔗糖、硼酸在一定浓度范围内能促进花粉萌发,含笑花粉萌发的最适蔗糖和硼酸分别为50 mg.L-1和5mg.L-1,萌发率分别为21.51%和44.14%;花粉最佳萌发温度为25℃,萌发率达53.33%。正交试验设计结果表明,花粉萌发的最佳组合为70 mg.L-1蔗糖+5 mg.L-1硼酸+28℃,萌发率可达65.33%。     

光、温度和土壤水分对坡垒种子萌发的影响

研究了温度,光照,土壤水分对坡垒（Hopea hainanensis Merr.et Chun)种子萌发和寿命的影响。结果表明坡垒种子萌发的最适温度为15－20℃种子在全黑暗条件与周期性光照条件下处理的萌发结果无明显差异。土壤含水量为20％－70％时种子能够萌发,而适宜的土壤含水量为30％－50％。在室内自然摊放第14天的发芽率为20％。18d完全丧失发芽能力。由于坡垒种子具有顽拗型种子的一些特点,该物种宜采取活体保存的方法,以就地保护为主,迁地保护为辅。     

Studies on the Germination of Pine Pollen (Pinus mugo) in vitro. I. Growth Conditions and Effects of pH and Temperature on Germination, Tube Growth and Respiration

The ability of pine pollen to grow in vitro is discussed in relation to its in situ. Optimal conditions of growth in vitro were investigated. All the experiments were made with pollen of Pinus mugo Turra. A satisfactory medium is described as that which at pH 5.2 and at 29 °C can lead to a tube growth bigger than in vivo. The initial growth (0–30) hours) in terms of tube growth and respiration is described in detail. It is shown that a correlation exists between tube growth and respiration. A method for estimating the metabolism and growth of the pollen tube, based on the uptake of ³²p-labelled phosphate, is described. Addition of known stimulators of plant growth and extension does not stimulate tube growth. Temperature studies show that under 20°C germination does not take place.