百合小鳞茎膨大发育过程中氮磷钾的吸收与分配规律

本文以周径为4～6cm的‘耀眼’（Evening Star）百合的小鳞茎为试材,研究了常规栽培条件下百合小鳞茎膨大发育过程中养分的吸收和分配规律。结果表明,百合小鳞茎在苗期以前,主要以消耗鳞茎中的养分为主;苗期后对营养元素的吸收量逐渐增大。营养元素的吸收高峰期在半枯期前后至采收期历时37天,氮、磷、钾的吸收比例为1:0.14:1.09。现蕾期以前,营养元素主要分配于茎叶中,各养分含量水平于苗期达最高;现蕾24天后养分分配以鳞茎中为主;分配于根系和新鳞茎中营养元素仅为10%左右。     

果梅不同物候期氮、磷、钾含量变化规律及特征

以盆栽的3年生细叶青梅/桃砧为试材，分别测定了不同物候期果梅各器官内氮、磷、钾的含量，结果表明：休眠期，果梅各器官都具有氮、磷、钾贮藏与供应能力；其中粗根贮藏与供应氮的能力最强；其它多年生器官均是贮藏与供应钾的能力最强。冬季花芽的进一步分化要求高浓度的钾、磷和相对低浓度的氮。从休眠期花蕾至新梢旺长期幼果，氮的含量呈上升趋势，而磷、钾的含量则有所下降。新梢旺长期，新梢争夺氮、磷、钾的能力强于幼果，其中新梢对氮、钾的需求量大致相等，而幼果对氮的需求量大于钾。花芽分化期，花芽的进一步分化、叶片功能的维持及各多年生器官的加粗都对三要素中钾素的依赖性更强。果梅体内氮、磷、钾有随生长中心转移而转移的特性。果梅吸收氮、磷的适宜时期为前一年花芽分化期之后至来年新梢旺长期；吸收钾的高峰期为新梢旺长期至花芽分化期。     

福建山樱花组培快繁研究

以福建山樱花(Prunus campanulata Maxim.)嫩枝作为外植体,接种到1 / 4MS＋BA1.0mg/L+IBA0.01 mg/L,可诱导大量丛生芽。增殖阶段,培养基MS＋BA1.0mg/L+GA0.3 mg/L有利于苗的快速繁殖,提高繁殖系数。最佳生根培养基配方为：1/2MS＋NAA1.0 mg/L＋IBA0.2 mg/L。     

磨盘柿杂种胚挽救中的生根壮苗培养

针对磨盘柿杂种胚挽救培养后的幼苗侧根少、直接成苗率低这一问题,采用对比法设计研究了在后续培养中几种措施的生根壮苗效应。结果表明:在原萌发培养基中添加1%墨汁可使胚挽救培养的直接成苗率提高到87%以上;对不能直接驯化移栽的胚挽救苗,短截主根和无糖培养措施能促进其侧根发育,并提高了幼苗的自养能力;3种措施的综合运用最终可使96%以上的杂种胚得以挽救成苗,并成功移栽于大田。     

盐生植物盐穗木种子和幼苗对干旱胁迫的响应

摘 要：以盐生植物盐穗木的种子和幼苗为材料，研究干旱胁迫下盐穗木种子的萌发特性和幼苗的生理变化，以确定其对干旱胁迫的适应能力。利用PEG人工模拟干旱胁迫，检测盐穗木种子萌发期和幼苗期生长指标和生理指标的变化。结果表明：高渗透势(-0.6~-0.4 MPa)对盐穗木种子萌发有促进作用，提高其初始萌发率，并缩短其达到最终萌发率的时间，且高渗透势处理的最终萌发率与CK无显著差异，而中、低渗透势(-2.0~-0.8 MPa)对盐穗木种子萌发则有抑制作用，降低其初始萌发率，并延长其达到最终萌发率的时间；中、高渗透势(-0.7~-0.3 MPa)刺激了盐穗木幼苗做出积极的生理反应，表现为相对电导率下降、可溶性糖含量增加、过氧化氢酶(CAT)和过氧化物酶(POD)活性增强；综合种子萌发期和幼苗期的表现，盐穗木对在中、轻度干旱环境（渗透势为-0.7~-0.3 MPa）有较好的适应。     

不同采收期黄桃的品质特性和微观结构变化

为研究不同采收期对黄桃果实品质特性和微观结构的影响,以4种不同采收期的锦绣黄桃为试验原料,对果实感官品质、质地、色差、微观结构、营养品质进行分析。结果表明:不同采收期的黄桃品质特性和微观结构不同。I期(7月25日采摘)到III期(8月8日采摘),随采收时间的推迟,黄桃果肉可溶性固形物、水溶性果胶、可溶性蛋白、VC含量逐步积累上升,但可滴定酸、原果胶含量逐步下降。I期和Ⅱ期(8月1日采摘)采收的果实硬度较高,微观组织结构紧密,营养品质低于III期。IV期(8月15日采摘)采收果实已过熟,果实软化,组织结构疏松,口感甜软,营养品质低于III期。III期(8月8日采摘)采收果实营养、感官品质最佳,为黄桃鲜食的最佳采收期。本研究为湖南炎陵锦绣黄桃的鲜食适期采收提供了理论依据。     

桃花粉活性检测和离体萌发特性的研究

果树花粉活力直接影响授粉、受精乃至座果。为了解果树品种的花粉生活力,给引种栽培和杂交育种工作创造有利条件,以桃花粉为试验材料,采用染色方法检测花粉的活性。试验结果表明,含有蓝墨水的花粉培养基,花粉萌发率可以达到64.67%,与对照相比差异不明显,因此该方法比较适合于快速检测花粉活性;固体培养基培养2个品种桃花粉,萌发率比液体培养基培养分别高25%和20%。另外温度、花粉密度、培养基中蔗糖及硼酸浓度都对花粉萌发率和花粉管长度有影响,在温度为24℃、1粒花药/100 μL、10%的蔗糖或100 mg/L的硼酸的条件下,均有利于花粉萌发和花粉管生长。     

Genetic resources in apple,pear and vineyard peach populations in former Yugoslavia

Summary During the period 1988–90, several germplasm collecting trips were made to all republics of former Yugoslavia. A total of 56 old apple cultivars, many of which are represented in up to 5 types, 38 old pear cultivars and 367 genotypes of vineyard peaches were collected. The availability of so much genetic and genotypic wealth made it possible to start apple disease resistance breeding and peach cultivar and rootstock breeding programmes.     

Differential cold sensitivity of pollen grain germination in two Prunus species

Summary Pollen grains from selected cutivars of almond [Prunus dulcis (Mill.) D. A. Webb] and peach (Prunus persica Batsch L.) were exposed to a range of temperatures between 1°C and 34°C on a thermogradient plate. Pollen germination at temperatures below 9°C was conspicuously greater in almond than peach. Miximal germination percentages were attained at about 16°C (almond) and 23°C (peach). The two species did not differ in their capacity for pollen tube elongation over a broad range of temperatures. Maximal pollen tube elongation occurred at temperatures 5°C to 8°C higher than maximal pollen germination. Species affiliation appeared to be of much greater consequence than chilling requirement or bloom date of the sporophyte in predicting gametophytic response to temperature.     

An in vitro assay for drought-tolerant coconut germplasm

Summary The feasibility of developing an in vitro technique for screening drought-tolerant coconut germplasm has been investigated. Embryos excised from mature nuts of Sri Lanka-tall coconut were cultured as described previously. Water-stress in the culture system was progressively increased with each passage, by incorporating polyethylene glycol (PEG-6000), mannitol and sodium chloride into the culture medium. PEG and mannitol were observed to be growth inhibitory in action event at low concentrations and these two compounds were abandoned. In NaCl-stressed media, about 21% of randomly selected Sri Lanka-tall embryos died before reaching the 170 mM NaCl. About 78% survived 170 mM NaCl and only 12.6% were able to resist 320 mM NaCl. When zygotic embryos derived from two known drought-susceptible cultivars of coconut, CRIC-65 and Dwarf (from pumila) were tested using the same technique, 29% and 73% of embryos respectively died due to stress damage caused by 170 mM NaCl and none of either cultivar survived a salt concentration above 230 mM.However, embryos originated from two putative drought-tolerant cultivars showed a higher survival rate when subjected to salt stress. At 170 mM NaCl, all the embryos had developed into seedlings. In fact, percent germination of embryos was somewhat higher in 170 mM NaCl than in the control, that was devoid of NaCl. However, percent survivors gradually dropped with increase in salt concentration and about 18% survived the 330 mM NaCl. The technique seems to have great potential in screening drought-tolerant coconut germplasm.     

Quantitative evaluation of the degree of sprout leaf bending of rice cultivars using P-type Fourier descriptors and principal component analysis

For decades, seedling peaches have been used as the standard rootstock in California almond orchards. Vigorous, deep rooted trees are needed in almond orchards for maximum yields and to withstand the annual tree-shaking at harvest. Currently, researchers are actively evaluating rootstocks for almonds in field trials and in various screening protocols. In this study, seedling rootstocks, obtained from male-sterile advanced generation peach-almond (PEAL) hybrid mother trees, were compared with ‘Nemaguard’ peach seedlings for emergence in the nursery row, trunk caliper at propagation time, and end of season dormant above ground tree weight. Seedling emergence was affected significantly (P ≤ 0.05) by seed source, as was trunk caliper and end of season dormant above ground tree weight. Trunk caliper and dormant above ground tree weight were also affected significantly (P ≤ 0.05) by planting year. Results obtained in this study demonstrate the enhanced first year growth from seedlings of advanced generation PEAL hybrids, as compared to ‘Nemaguard’ seedlings. Seedling emergence in the rootstock bed was not affected significantly by planting year. Advanced generation PEAL hybrid seedlings were ready for June-budding at an earlier date compared to ‘Nemaguard’ seedlings, providing the potential for larger-sized finished nursery stock by the end of the growing season. Due to the male-sterile status of the advanced generation PEAL mother trees, bloom periods of several root-knot nematode resistant rootstock cultivars were examined for their degree of synchronicity with the mother trees. The examined rootstocks and mother trees varied in both chill hour and post-chill heat requirements necessary to effect bloom. ‘Flordaguard’ peach rootstock began bloom in advance of the male-sterile mother trees, whereas the bloom period of ‘Tsukuba No. 4’ occurred well after, suggesting they would not be effective synchronous pollenizers for consistent hybrid seed production. Based on more limited flowering period data, better bloom synchronicity was achieved with a Tsukuba No. 4 X Flordaguard hybrid.     

Multivariate analysis of vineyard peach [Prunus persica (L.) Batsch.] germplasm collection

Thirty vineyard peach [Prunus persica (L.) Batsch.] genotypes were studied to determine the overall degree of polymorphism and to detect similarities among genotypes. The variation was observed for traits related to phenology, morphology, yield and fruit quality. Many fruit characteristics that are important to breeders are present in this collection. The majority of important correlations were determined between the characteristics representing fruit size (fruit width, fruit height, fruit weight and stone weight) and between those ones representing fruit quality (fruit attractiveness, taste, flavour and soluble solids content). Cluster and principal component analysis showed a considerable phenotypical diversity in the vineyard peach germplasm. Clustering of genotypes was in accordance with its purpose (fresh consumption or rootstocks production). Parameters with high discriminating values were those related to fruit size and fruit quality.     

光照和盐分对醉马草种子萌发的影响

研究了光照、水分和盐分对醉马草种子萌发的影响.结果表明,醉马草种子萌发对光照不敏感,在黑暗和光照下的发芽率及幼苗长度没有显著性差异.NaCl和等渗透势的PEG对种子的萌发均产生抑制作用,降低了发芽率,且PEG的抑制程度大于等渗NaCl,说明渗透胁迫是影响醉马草种子萌发的主要因素.醉马草种子能在0～398 mmol/L的NaC1浓度下萌发,较低盐浓度有利于根长的生长.     

陆地棉体细胞植株再生及其移栽技术研究

以7个陆地棉（Gossypium hirsutum L.）品种为材料，对体细胞植株再生及移栽技术进行了研究。在含IAA和KT和0.5ppm的MSB培养基上，Coker312、Coker201、鲁棉1024、冀合3016和河南79等5个品种能形成数量不等的胚性愈伤组织，中棉12和邯郸14的愈伤组织继代后便褐化死亡。胚性愈伤组织振荡培养1个月以上转移到成熟培养基上获得大     

Induction and development of adventitious shoots of Atropa baetica as a means of propagation

In vitro propagation of Atropa baetica was established employing axillary buds. Single buds were cultured through a multiple shoot induction phase, rooting phase, and then followed by acclimatization in soil. For multiple shoot induction, Murashige and Skoog (MS) medium with 3% sucrose, supplemented with either 0.75 or 1.25 mg l^-1 of BAP provided the best results with an average of 5.6 shoots per explant after 31 days of culture. Similar results were obtained with higher BAP concentrations (1.75–2.0 mg l^-1); however, these media had a negative effect on the subsequent root induction due to residual BAP effect. Medium containing only 0.25 mg l^-1 of BAP induced a significantly lower number of shoots. Root induction occurred spontaneously after transferring the shoots onto MS medium lacking any plant growth regulator. Moreover, root induction also occurred on media supplemented with 0.125 and 0.25 mg l^-1 of NAA. On these two rooting media, this response was more prominent and with a higher number of roots per explant. Nevertheless, after 28 days on root induction medium, the number of rooted plantlets was similar on the three media. Acclimatization of plantlets in soil was very successful (95.52%). However, all plantlets which died during acclimatization were rooted on medium containing 0.25 mg l^-1 NAA suggesting a negative carry over effect of this medium upon plantlet survival, irrespective of the initial BAP treatment used. On the other hand, karyological studies showed no variation in the number of chromosome (2n=72) in root tips of the plantlets produced. This revised version was published online in July 2006 with corrections to the Cover Date.     

玉米种子萌发期抗旱性鉴定方法及不同杂交种抗旱性比较研究

用PEG-6000高渗溶液模拟土壤水分胁迫的方法,比较了培养介质、浸种时间对不同粒质量类型玉米种子发芽率的影响,并采用砂培不浸种方式,研究了黄淮海地区近几年审定的32个玉米杂交种萌发期的抗旱性。结果表明:不同类型的玉米品种,在纸培模式下20%PEG渗透胁迫处理的发芽率均低于或等于25%,远低于砂培模式。砂培模式下,不浸种处理的发芽率总体好于浸种24 h和48 h处理。砂培不浸种方式下,渗透胁迫处理不同程度地降低了32个玉米杂交种种子的发芽率;大多数品种初生根条数低于对照,胚芽长和胚根长均减小,胚芽长比胚根长减小的程度大,胚芽干质量显著降低。     

Parameters of cold tolerance in common vetch

Summary The cold tolerance of 16 common vetch (Vicia sativa L.) strains was assessed by means of survival rate after direct freezing. Additionally, several seed and seedling parameters, germination in solution with osmotic pressure, and electrolyte exosmosis from shoots and from roots of seedlings were determined. The U.S. cv's Nova II, Vanguard and Warrior and the Turkish cv. Sari Elçi exhibited survival rates higher than 75% after direct freezing test, compared to less than 40% in the remaining entries. Simple correlation analysis showed that only electrolyte exosmosis from shoots after freezing was negatively correlated with survival rate.     

药百合种子萌发及染色体倍性检测

以浙江省广布种药百合为材料,采用不同激素浓度的培养基进行种子诱导及萌发实验,以不添加任何激素的MS培养基为对照,对药百合种子萌发率、诱导率、诱导芽数及生长势等进行研究,同时,对药百合种子诱导所形成试管苗进行染色体制片常规技术分析。结果表明,添加不同激素浓度培养基能显著促进药百合种子萌发,最佳培养基为MS+6-BA1.0 mg.L-1+NAA0.1 mg.L-1,萌发率为83.3%,诱导率为88.9%,平均诱导不定芽数达2.5个;未经剥皮处理的种子在30 d时仍无任何萌动;将诱导后的种子转至MS基本培养基中,仍表现出与转接前一致的生长状态;93%以上种子属于子叶出土型,仅接种在高浓度6-BA（1.0 mg.L-1）及低浓度NAA（0.1～0.2 mg.L-1）培养基上的种子有少量表现为种子留土型,占4%;种子萌发试管苗染色体倍性为2n=2x=24,未发生遗传变异。     

黍稷芽、苗期抗旱性评价及抗旱资源鉴定

为了全面了解中国现存黍稷种质资源的抗旱性,研究黍稷在PEG6000模拟干旱胁迫下的抗旱表现,挖掘优异抗旱种质并筛选抗旱鉴定指标,本研究以前期构建的包含230份资源的黍稷微核心种质为试验对象,开展室内PEG6000模拟干旱胁迫处理下的芽、苗期抗旱性研究。通过对芽期和苗期抗旱性指标的测定发现:干旱胁迫下,芽期和苗期各指标较对照组均有下降趋势;芽期指标变异系数较苗期偏大,苗期根鲜重变异系数最大,根干重、苗鲜重、苗干重其次(变化范围在0.35~0.50之间)。相关性分析显示多数指标间相关性都达到了显著或极显著水平,其中相对根鲜重与相对根干重的相关性最高,而相对叶绿素含量与相对根长、相对苗长、相对根鲜重及相对苗干重的相关性均较低。采用平均值-标准差逐级分级法和分层聚类分析综合鉴定参试黍稷芽期和苗期抗旱性,发现芽期极强抗旱、强抗旱材料分别为3份和10份,苗期极强抗旱、强抗旱材料分别为24份和23份;其中紫秆黍(00003289)、乌克兰黍(00006438)和白糜子(00000101)三个品种在芽期和苗期均有很好的抗旱性,可作为后续全生育期抗旱研究和抗旱品种选育的优良资源。对芽期及苗期各抗旱鉴定指标进行相关性分析,结果表明芽期与苗期抗旱性没有显著相关性;主成分分析表明,相对苗长、相对苗鲜重以及相对叶绿素含量可作为评价黍稷苗期抗旱性鉴定的主要指标。     

Response of Wheat and Barley during Germination to Seed Osmopriming at Different Water Potential

Pre-sowing osmotic seed treatments were evaluated as a means of improving water uptake and germination performance of wheat ( Triticum durum L. cv. Hourani-27) and barley ( Hordeum vulgare L. cv. ACSAD 176) under four levels of water potential (0, –0.4, –0.8 and –1.2 MPa) created by using polyethylene glycol 8000. Seeds were osmoprimed in aerated solutions of 0.0, 0.2, 0.4 or 0.6 M KCl at 24 ± 2°C overnight and then rinsed and dried. Rate of water uptake by seeds was higher in osmoprimed than untreated seeds of both crops regardless of the water potential level. Decreasing water potential (more stress) adversely affected rate of water uptake in seeds of both crops. Seeds osmopriming increased germination percentage and decreased time to 50% germination at high water potentials (low stress), whereas the germination at low water potentials (more stress) was not affected by osmopriming treatments. The effect of osmopriming on rate of water uptake, germination percentage, and time to 50% germination was more pronounced in wheat than in barley. Reduction in the lag time of imbibition may be accounted for in part by some germination rate enhancement in the osmopriming treatments. Fresh weight and length of shoots (plumules) and roots (radicles) were enhanced in osmoprimed seeds in comparison to untreated seeds, in both crops at high water potentials (0 and – 0.4 MPa). As water potential in the medium decreased, these traits were inversely affected regardless of osmopriming treatment. Longer roots in wheat compared to barley were noted in the positive osmopriming treatments at high water potentials (0 and – 0.4). These results might indicate that wheat is more responsive than barley at relatively high water potentials to osmopriming through rapid penetrating root system.