柑橘果实生长发育过程中果实不同部位的4种内源激素含量变化的研究

以单性结实的国庆1号温州蜜柑和自花结实的华农本地早橘为材料,研究了果实生长发育过程中果实不同部位的吲哚乙酸(IAA)、脱落酸(ABA)、赤霉素(GA1/3)和玉米素核苷(ZR)含量的变化。结果表明:(1)国庆1号果皮IAA、GA1/3和ZR含量在幼果阶段均相对较高,随后果皮和果肉IAA含量均趋下降,而在果实膨大期内果肉ABA和果皮、果肉GA1/3、ZR含量均出现上升峰值,果实成熟采收时果皮和果肉ABA含量均明显回升。(2)华农本地早种子、果皮和果肉IAA及其种子ABA含量均在果实膨大期内出现明显峰值,在幼果阶段至果实膨大初期内种子GA1/3和ZR含量均居较高并出现明显上升,对应的果皮、果肉4种内源激素水平均相对较低且变幅小。还就两结实类型柑橘果实生长发育与其内源IAA、ABA、GA1/3和ZR含量动态的关系进行了讨论。     

乌桕果实生长发育的观察及其营养物质积累的分析

<正> 乌桕(Sapium sebiferum(L. )Roxb. )是我国南方分布和栽培较广的油料树种。乌桕种子含有丰富的油脂,其油脂是重要的化工源料和传统的出口商品。如能掌握乌桕果实的生长发育及油脂物质积累规律,在生产上,可根据不同生长发育阶段采取相应的技术措施,以达到增产的目的。 为此,我们从1979年开始对乌桕果实进行定期观测和采样分析。现将试验结果,作简要的报道,供有关方面参考。     

珠子参根茎结构特征与皂苷积累的动态变化关系

皂苷类物质是珠子参根茎内贮存的重要次生代谢物质。根据皂苷类物质的化学性质,采用组织化学定位、显微制片技术和皂苷定量分析方法对不同生长年限珠子参的根茎节部进行了解剖学与皂苷动态积累的关系研究。结果表明:珠子参根茎节部横切面结构复杂,具有2至多个维管柱,属异常结构。珠子参根茎节部的加粗生长依赖于次生结构与三生结构的发生和分化。根茎节部分泌腔周围的分泌细胞、次生韧皮和三生韧皮部是珠子参皂苷类物质主要积累场所。随着珠子参生长年限的延长,根茎节部分泌腔、异常维管柱的数目及皂苷的含量增加。分泌腔、异常维管柱的数量和相对密集的节部可作为珠子参优良品种选育的结构和形态指标。     

宁夏枸杞果实生长发育期内源激素变化及关系研究

以‘宁杞1号’枸杞为材料,采用高效液相色谱技术,对不同发育时期宁夏枸杞果皮和种子内源激素(ZT、GA3、IAA、ABA)含量进行测定,以揭示其变化规律.结果显示:(1)种子中的生长素与果实横径和果实单粒重均呈极显著的正相关关系,与果实纵径呈显著正相关关系,即种子中的生长素在果实的增大中起着重要的作用.(2)果皮和种子中的赤霉酸含量都远远大于其他3种激素含量,且从第一次快速生长期(花后2～8 d)到缓慢生长期(花后8～25 d),其含量与种子中的生长素含量变化较为一致,进入第二次快速增长期(花后25～33 d)以后,果皮和种子中赤霉酸的含量则迅速下降,而种子中的生长素含量却急速上升,这可能是果皮和种子中的赤霉酸促进了种子内生长素的合成,而种子内的生长素可以直接调节果实细胞的伸长.研究表明,‘宁杞1号’种子中的内源激素在果实生长发育中起着重要的作用,且各激素间存在着平衡关系,果皮和种子中各种激素相互影响,共同促进果实的生长发育.     

滇重楼采收期研究

目的:获得滇重楼栽培的采收周期和采收的最佳时间。方法:采用高效液相色谱分析不同生长年龄(1~8年)的滇重楼种子苗地下根茎的皂苷含量,每月分析滇重楼地下根茎的皂苷含量;称取滇重楼地下根茎的重量,获得滇重楼种子苗地下根茎的年度生长特点,获得滇重楼地下根茎生长发育的月度变化规律。结果:滇重楼种子苗地下根茎的皂苷含量随栽培年限的增加,含量增高,第七年达到最高,第四年达到药材标准;地下根茎的发育从第四年进入快速生长期。一年之中,滇重楼地下根茎的皂苷含量,7月份最高,6月份最低。地下根茎的生长旺盛期从6月份开始,10月份达到顶峰。结论:滇重楼的采收周期以7年为宜,采收的最佳时间为10月份。     

宁夏枸杞果实内源激素的变化及其与细胞壁成分和相关酶的关系

采用高效液相色谱技术, 研究了不同发育时期宁杞1号和宁杞5号枸杞(Lycium barbarum)果皮和种子内源激素(玉米素(ZT)、赤霉素(GA₃)、生长素(IAA)和脱落酶(ABA))含量与果实生长发育的关系。结果表明, 宁杞5号果实横纵径和单粒重均大于宁杞1号, 果实发育前期, 尤其是缓慢生长期, 是宁杞5号果实大小和重量积累的关键时期。宁杞1号种子中的生长素含量与果实横径和果实单粒重均呈极显著正相关, 与果实纵径呈显著正相关。宁杞5号果皮中玉米素含量与果实横径和单粒重均呈显著正相关, 种子中生长素含量与果实横径和单粒重均呈显著正相关。玉米素促进细胞的分裂, 而细胞数目比细胞体积对决定果实大小的作用更大; 在缓慢生长期(开花后8–25天), 宁杞5号果皮和种子中的脱落酸含量均显著小于宁杞1号。以上两点可能是宁杞5号的横纵径和单粒重均大于宁杞1号的主要原因。宁杞1号果皮中的GA₃与半纤维素酶(Cx)活性的变化相反, 说明宁杞1号果实发育前期和中期果皮中高含量的GA₃对细胞壁中Cx活性有一定的抑制作用, 从而表现出果实膨大。宁杞5号果皮中的IAA与多聚半乳糖醛酸酶(PG)和果胶酯酶(PE), ZT与PE, ABA与Cx, 种子中的ZT与PE的变化均相反, 说明宁杞5号果实发育前期和中期果皮中高含量的IAA、ZT、ABA及种子中的ZT可促进果实的膨大。推测这可能是宁杞5号果实单粒重大于宁杞1号的主要原因之一。宁杞5号果皮中的ZT和种子中的IAA可以增强Cx的活性; 宁杞1号果皮中的ABA可以增强PE的活性, 进而促进果实的成熟。     

基于种实性状的无患子天然群体表型多样性研究

无患子(Sapindus mukorossi Gaertn.)是我国长江以南地区传统的重要绿化树种,其果皮富含皂苷,种仁富含油脂,是国家林业局审定的新型木本油料树种之一。为揭示无患子群体间和群体内种实表型性状变异式样,采用单因素方差分析、巢式方差分析、相关分析和主成分分析等方法,对无患子13个天然群体的10个种实表型性状进行比较分析,研究其群体间和群体内种实表型多样性以及表型变异与地理生态因子间的相关性。结果表明:无患子种实表型性状变异系数平均为7.34%,在群体间和群体内均存在丰富的表型变异。表型性状分化系数平均为62.21%,群体间变异(39.93%)大于群体内(27.46%),是无患子种实表型性状变异的主要来源。多数性状在群体间差异显著,不同程度的表现出边缘群体易于分化的特点,但地理变化规律不连续,而在群体内不同性状的差异性亦不一致。种子形态受群体地理生态的影响较果实形态大,西北部群体种子趋于椭圆形,东部、南部则趋于圆球形;地理纬度、年平均气温与多数种实性状间呈显著相关,是无患子种实表型性状变异的主要地理生态影响因子。可见,无患子种实表型性状在群体间、群体内变异都较为丰富,这些变异是由遗传和环境因素共同作用的结果。群体间和群体内多层次的变异为无患子优良种质资源保育和利用提供了物质基础。     

不同生长年限白头翁根的解剖结构与皂苷组织化学定位研究

皂苷类物质是白头翁的重要药用成分,主要存在于根内。研究白头翁根的解剖结构与皂苷类物质的关系有重要意义。利用解剖学和组织化学定位方法对不同生长龄白头翁根的解剖结构和皂苷的储藏场所进行了研究.结果表明:栓内层和次生韧皮部中的分泌细胞团、分泌腔和分泌道是白头翁根的主要结构特征,是皂苷类物质的主要贮存场所;而分泌腔和分泌道的数量及分泌道的宽窄与生长年限相关,4~5年生达到最大值。推测白头翁的栽培年限应为4年。     

温度及pH对自絮凝小球藻JSC-7生长的影响（英文）

微藻是可广泛用于健康食品及水产养殖的饵料,同时,微藻细胞内积累的油脂可作为可再生生物燃料,因此微藻的生长和代谢受到广泛关注。温度和pH对微藻的生物量积累有很大影响,考察不同温度和pH条件下微藻细胞的生长有助于寻找最佳的条件进行微藻的培养。自絮凝小球藻JSC-7(Chlorella vulgaris JSC-7)可实现自沉降采收,有利于降低微藻生产成本,优化其生长条件对更好地利用该微藻具有重要意义。考察了温度(22~40℃)及pH(6.0~10.0)对其细胞生长、叶绿素含量和油脂产量的影响。在所选取的温度及pH范围内,JSC-7细胞均可生长,显示该藻种可以适应广泛的温度和pH条件。适合细胞生长的温度依次为31℃28℃35℃25℃,pH依次为7.08.06.0。pH 8.0时生物量和油脂的积累量最多,说明该藻株在弱碱条件下更适合生长和产油。当温度为31℃、pH为7.0时,可获得最高的生长量(OD690=0.941)、叶绿素含量(19 mg/L)及油脂产量(39.07%/克干重)。     

补骨脂中呋喃香豆素类物质的积累规律及组织定位

应用高效液相色谱技术,分析了补骨脂(Psoralea corylifolia)不同器官、不同发育时期补骨脂素和异补骨脂素的含量变化规律。2种呋喃香豆素类物质在补骨脂的根、茎、叶、花、果实和种子中均有积累,其含量在果实中最高,根中最低,幼嫩茎叶高于成熟茎叶,成熟期果实高于幼嫩期果实。通过组织化学和荧光显微技术对呋喃香豆素类物质的定位研究,同时结合分泌腔的系数与2种呋喃香豆素的含量相关性分析,证明补骨脂中分泌腔是2种呋喃香豆素积累的主要场所。     

Synergistic/potentiation interaction between nematostatic constituents from Azadirachta indica,Madhuca indica and Sapindus mukorossi

Triterpenic saponins isolated from seeds of Madhuca indica and fruit pericarp from Sapindus mukorossi exhibited inhibitory effect against two phyto-parasitic nematodes. Azadirachtin and salanin-nimbin-desacetylnimbin (SND) was extracted from seeds and oil of Azadirachta indica A. Juss, respectively. M. indica and S. mukorossi saponins were found to inhibit the movement of pre-adult (J₄) stage of Rotylenchulus reniformis with LC₅₀ of 168.8 and 181.9 µg/mL. Azadirachtin and SND affected the mobility of secondary juvenile stage (J₂) of Meloidogyne incognita by 83.3 and 80.1% respectively, at 0.5 mg m/L. M. indica saponin (LC₅₀ 220 µg/mL) exhibited a potentiation effect in the presence of azadirachtin in a 1:3 ratio (LC₅₀ 120.1 µg/mL). A binary mixture (1:1) of azadirachtin and SND was found to show significant nematicidal activity against M. incognita (LC₅₀ 70.9 µg/mL) and R. reniformis (LC₅₀ 91.2 µg/mL).     

浙江低山地区多用途植物无患子的开花物候特征

无患子(Sapindus mukorossi Gaertn.)是我国长江以南地区传统的重要绿化树种,其果皮富含皂苷,种仁富含油脂,是国家林业局审定的新型木本油料树种之一。为研究多用途树种无患子在浙江低山地区的开花特征,2012年和2013年连续两年对位于浙江省天台县9年生无患子人工林在群体、个体、花序和单花水平进行开花物候观测和比较,并运用开花日期、相对开花强度和同步性等指数研究了无患子开花物候特征。观察结果显示:无患子花呈浅黄白色,花的类型有雄花和两性花,没有发现雌花。雄花较两性花大(花径分别为5.09 mm和3.72 mm),雄蕊多为8枚,个别7或9、10枚;雌蕊退化仅留下浅绿色凸起。两性花花萼稍抱拢,花药藏于花被片下,雄蕊大多8枚,极少数7枚或9枚,柱头高于花药并伸出花苞,子房一般具3室,极少数4室或仅2室。无患子2012年的开花进程略早于2013年,其花期集中在在5月中旬至6月上旬,单花从花蕾膨大到花朵凋谢一般为8—9 d。在2012年和2013年,无患子在群体、个体和花序水平的花期约为30 d、20 d、11 d和28 d、19 d、13 d。个体水平的开花振幅均呈单峰曲线,年际间相似性较高;开花同步性在个体水平同步性较高(同步指数为0.868),表现出一种大量、集中的开花式样;相对开花强度在单株间分布范围相对宽泛,但主要分布在30%—40%,在年际间和年际内均呈现极显著差异。花期同步指数在两年的变异范围分别是0.81—0.97和0.70—0.98,不同单株开花同步性在年际内差异极显著,但在年际间差异性则不显著。由此可见,无患子的生殖资源分配存在明显的时空差异,较长的花期可以减少非法花粉的干扰、保持其种群基因多样性,遗传因子是决定无患子开花物候的主要因素,生态环境对无患子开花物候的影响还需进一步研究,本研究以期为探索无患子开花的主要限制因子奠定基础。     

Tentative Identification of Phytochemicals and Antioxidant Activities during Fruit-Ripening on <i>Chamaedorea radicalis</i> Mart.

This work aims to determine the phytochemical characterization of the pericarp of Chamaedorea radicalis Mart. fruit as a non-timber product with potential to obtain phytochemicals with potential applications in the industry. Fruit from C. radicalis were grouped in four ripening stages named as S1, S2, S3 and S4, according to maturity; S1 the most unripe stage and S4 the completely ripe stage. Determinations of total phenolic compounds, free radical scavenging activities and total flavonoid contents using spectrophotometric methods were done. Also, the tentative identification of phytochemicals during fruit ripening was done using UPLC-MS-MS. Total phenolic compound (TPC) content ranged from 7.24 to 12.53 mg gallic acid equivalents per gram of fresh weight (mg GAE/ g FW). Total flavonoids (TF) contents ranged from 0.163 to 0.23 mg of quercetin equivalents per g FW (mg QE/g FW). Free radical scavenging activity against DPPH and ABTS radicals varied from 40.80 to 53.68 and from 22.29 to 37.76 mmol Trolox equivalents g FW (mmol TE/g FW), respectively. Antioxidant assay in vitro by FRAP (ferric reducing antioxidant power) method showed that S3 was the highest level with antioxidant power while S4 was the lowest with Red ripeness stage showed the lowest contents for all determinations. Mass spectrometry allowed detection of 26 compounds, including phenolics, alkaloids and saponins. Afzelin, Kaempferol 3-neohesperidoside and the four saponins identified were present in all ripeness stages. Preliminary phytochemical identi- fication and the spectrophotometric determinations showed that the pericarp of C. radicalis presented antioxidants and compounds related to alkaloids, phenolics and saponins. The presence and abundance of each phytochemical regarding each ripeness stage should be considered.     

Physical and chemical properties of fruit and seeds eaten byPithecia andChiropotes in Surinam and Venezuela

Pithecia pithecia andChiropotes satanas are seed predators that eat fruits with hard pericarps. We measured resistance to puncturing and crushing of fruit and seeds eaten by these two pitheciins at two localities: in evergreen rain forest at Raleighvallen-Voltzberg, Surinam, and in tropical dry/transitional moist forest on islands in Guri Lake, Venezuela. Average measurements of pericarp hardness were similar at both sites for fruit eaten byChiropotes, but a higher maximum value was obtained at the rainforest site.Chiropotes andPithecia both ate fruits that had harder pericarps than did fruits eaten byAteles paniscus, but crushing resistances of seeds eaten were lower than values forAteles. Thus, both pitheciins selected fruits with hard pericarps and soft seeds, although there were notable intergeneric differences in hardness of fruit ingested. When fruit became scarce,Pithecia ate more flowers, whileChiropotes continued to eat fruits with hard seed coverings. Chemical analysis of species of seeds eaten byPithecia suggests that they avoided seeds with extremely high tannin levels, though they tolerated moderate tannin levels in combination with high levels of lipids. We propose that sclerocarpic harvesting (the preparation and ingestion of fruit with a hard pericarp) allows pitheciin monkeys to obtain nutritious seeds, with reduced tannins, that are softer than those ingested by other frugivores.Presented at XIIIth Congress, International Primatological Society, July 27, 1990.     

不同产地苦楝苗期生长节律研究

苦楝在我国分布广泛,具有丰富的遗传变异性。为进一步做好苦楝种源筛选和良种选育工作,该文对不同产地苦楝实生苗生长性状和各阶段的生长特点进行了比较分析,初步揭示了苦楝苗期生长规律。以15个产地的1年生实生苗为试材,对苗高、地径、复叶生长及生物量积累等生长性状进行了观测分析,并用Logistics方程对生长节律进行了拟合。结果表明:(1)不同产地苦楝苗高、地径生长差异均达显著水平,根生物量、茎生物量及复叶相关性状差异均达极显著性水平;(2)苗高和地径生长均呈现慢-快-慢的S型生长规律,且均存在2次生长高峰,与苗高生长高峰出现时间相比,地径生长高峰出现时间较晚;(3)Logistic拟合方程的R²为0.976～0.994,均达到极显著相关水平,说明可用Logistic方程拟合苦楝的生长节律;(4)总体上地径速生期较苗高速生期长20～30 d,北方产地苗高和地径进入速生期和结束速生期的时间均早于南方产地,速生期苗高和地径累积生长量均超过总生长量的60%;(5)各生长指标均与纬度负相关,苗高、生物量及复叶面积与经度正相关,其他指标与经度负相关。综上结果表明,苦楝为全期生长型树种,各生长性状在产地间达显著差异水平,生长受纬度和经度双重控制,以纬度控制为主。     

椰子脂肪酸积累及与FatB基因表达关系研究

为筛选控制椰子果实中低碳链脂肪酸积累的关键FatB基因,本研究以海南本地高种绿椰四个发育时期的果实为试验材料,参考国家标准GB/T2906-1982谷类、油料作物种子粗脂肪测定方法,用索氏提取法提取果肉脂肪酸,应用气质联用检测技术测定各发育时期脂肪酸含量及组分,同时应用qRT-PCR对椰子脂肪酸合成相关基因FatB1、FatB2及FatB3进行相对定量分析,明确各发育时期椰子果实脂肪酸积累与FatB基因表达量变化之间的关系。结果表明:(1)椰子油含9种脂肪酸成分,在椰子果实发育的早期(第6和第7个月),棕榈酸、硬脂酸和油酸的含量较高,月桂酸和肉豆蔻酸相对含量较低,通过实时荧光定量PCR发现,此时FatB1基因的相对表达量较高。(2)而在椰子果实发育的后期(第8和第9个月),棕榈酸、硬脂酸和油酸的相对含量迅速降低,月桂酸和肉豆蔻酸相对含量迅速升高,FatB2和FatB3基因的相对表达量较高,FatB1的表达量略有降低。该研究初步掌握了椰果各发育时期FatB基因表达量与脂肪酸成分间的变化趋势,该结果为将来筛选控制椰子果实中低碳链脂肪酸积累的关键FatB基因奠定基础,同时为椰子脂肪酸成分的分子改良提供理论依据。     

Fruit harvesting time and corresponding morphological changes of seed integuments influence in vitro seed germination of <Emphasis Type="Italic">Dendrobium nobile</Emphasis> Lindl.

In vitro asymbiotic seed germination of Dendrobium nobile varied significantly with fruit harvesting time and growth medium used for culturing seeds. Seeds harvested 129 days after pollination (DAP) possessing globular shaped embryos and a discontinuous cuticle layer showed a substantially greater germination on P668 medium. Alternatively, immature seeds harvested 96 and 116 DAP displayed a significantly lower germination response on various growth media. Most of the ovules at 96 DAP are in archesporial and megaspore mother cell stages, whereas the majority of ovules are mature and fertilized at 116 DAP. Mature seeds harvested 158 DAP also germinated at a higher frequency at Stage 5 (emergence of the first leaf) after 8 weeks of culture on different growth media indicating the absence of testa imposed dormancy in this endangered epiphytic orchid.     

Differences in regulation of carbohydrate metabolism during early fruit development between domesticated tomato and two wild relatives

Early development and growth of fruit in the domesticated tomato Solanum lycopersicum cultivar Money Maker and two of its wild relatives, S. peruvianum LA0385 and S. habrochaites LA1777, were studied. Although small differences exist, the processes involved and the sequence of events in fruit development are similar in all three species. The growth of developing fruits is exponential and the relative growth rate accelerates from 5 days after pollination (DAP 5) to DAP 8, followed by a decline during further development. Growth is positively correlated to the standard “Brix plus starch’’ in the period DAP 8–DAP 20. Carbohydrate composition and levels of sugars and organic acids differ in fruits of the wild accessions compared to domesticated tomato. The wild accessions accumulate sucrose instead of glucose and fructose, and ripe fruits contain higher levels of malate and citrate. The enzymes responsible for the accumulation of glucose and fructose in domesticated tomatoes are soluble invertase and sucrose synthase. The regulation of initial carbohydrate metabolism in the domesticated tomato differs from that in the wild species, as could be concluded from measuring activities of enzymes involved in primary carbohydrate metabolism. Furthermore, changes in the activity of several enzymes, e.g., cell wall invertase, soluble invertase, fructokinase and phosphoglucomutase, could be attributed to changes in gene expression level. For other enzymes, additional control mechanisms play a role in the developing tomato fruits. Localization by in-situ activity staining of enzymes showed comparable results for fruits of domesticated tomato and the wild accessions. However, in the pericarp of S. peruvianum, less activity staining of phosphogluco-isomerase, phosphoglucomutase and UDP-glucosepyrophosphorylase was observed. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Seeds of tomato (Lycopersicon esculentum Mill.) which develop in a fully hydrated environment in the fruit switch from a developmental to a germinative mode without a requirement for desiccation

Seed water content is high during early development of tomato seeds (10–30 d after pollination (DAP)), declines at 35 DAP, then increases slightly during fruit ripening (following 50 DAP). The seed does not undergo maturation drying. Protein content during seed development peaks at 35 DAP in the embryo, while in the endosperm it exhibits a triphasic accumulation pattern. Peaks in endosperm protein deposition correspond to changes in endosperm morphology (i.e. formation of the hard endosperm) and are largely the consequence of increases in storage proteins. Storage-protein deposition commences at 20 DAP in the embryo and endosperm; both tissues accumulate identical proteins. Embryo maturation is complete by 40 DAP, when maximum embryo protein content, size and seed dry weight are attained. Seeds are tolerant of premature drying (fast and slow drying) from 40 DAP.Thirty-and 35-DAP seeds when removed from the fruit tissue and imbibed on water, complete germination by 120 h after isolation. Only seeds which have developed to 35 DAP produce viable seedlings. The inability of isolated 30-DAP seed to form viable seedlings appears to be related to a lack of stored nutrients, since the germinability of excised embryos (20 DAP and onwards) placed on Murashige and Skoog (1962, Physiol. Plant. 15, 473–497) medium is high. The switch from a developmental to germinative mode in the excised 30- and 35-DAP imbibed seeds is reflected in the pattern of in-vivo protein synthesis. Developmental and germinative proteins are present in the embryo and endosperm of the 30- and 35-DAP seeds 12 h after their isolation from the fruit. The mature seed (60 DAP) exhibits germinative protein synthesis from the earliest time of imbibition. The fruit environment prevents precocious germination of developing seeds, since the switch from development to germination requires only their removal from the fruit tissue.Abbreviations DAP days after pollination - kDa kilodaltons - SP1-4 storage proteins 1–4 - SDS-PAGE sodium dodecyl sulphate-polyacrylamide gel electrophoresis - HASI hours after seed isolation - MS medium Murashige and Skoog (1962) medium This work is supported by National Science and Engineering Research Council of Canada grant A2210 to J.D.B.     

Characterization of tomato endo-β-1,4-glucanase Cel1 protein in fruit during ripening and after fungal infection

The tomato (Lycopersicon esculentum Mill.) endo--1,4-glucanase (EGase) Cel1 protein was characterized in fruit using specific antibodies. Two polypeptides ranging between 51 and 52 kDa were detected in the pericarp, and polypeptides ranging between 49 and 51 kDa were detected in locules. The polypeptides recognized by Cel1 antiserum in fruit are within the size range predicted for Cel1 protein and could be derived from heterogeneous glycosylation. Cel1 protein accumulation was examined throughout fruit ripening. Cel1 protein appears in the pericarp at the stage in which many ripening-related changes start, and remains present throughout fruit ripening. In locules, Cel1 protein is already present at the onset of fruit ripening and remains constant during fruit ripening. This pattern of expression supports a possible role for this EGase in the softening of pericarp tissue and in the liquefaction of locules that takes place during ripening. The accumulation of Cel1 protein was also analyzed after fungal infection. Cel1 protein and mRNA levels are down-regulated in pericarp after Botrytis cinerea infection but are not affected in locular tissue. The same behavior was observed when fruits were infected with Penicillium expansum, another fungal pathogen. Cel1 protein and mRNA levels do not respond to wounding. These results support the idea that the tomato Cel1 EGase responds to pathogen infection and supports a relationship between EGases, plant defense responses and fruit ripening.This revised version was published online in August 2004 with corrections to Fig. 1 and Fig. 5.