贮藏温度对毛竹春笋采后生理的影响

以毛竹春笋为试材,在低温(4℃)和常温(15℃左右)条件下贮藏,在贮藏的第0、2、4、6、8天测定笋的水分、呼吸强度、灰分含量以及与笋氧化和木质化密切相关的酶活力水平,研究低温贮藏对毛竹春笋采后生理的影响。结果显示,低温贮藏条件下的毛竹笋水分散失量、呼吸强度和灰分含量都低于常温条件下的毛竹笋,且在贮藏第8天3个指标在2种温度条件下的差异达显著性水平;低温条件下毛竹笋的过氧化物酶活性在贮藏的第8天显著低于常温条件下的,而多酚氧化酶活性在贮藏的第4天显著低于常温条件下的。研究结果表明,低温贮藏有利于维持毛竹笋的食用品质和外观品质。     

高温胁迫对马银花的生理指标影响

通过人为模拟高温环境,观察马银花(Rhododendron ovatum)叶片生理指标变化情况及生长情况,分析其适应高温环境的能力。结果显示:(1)随着处理时间的延长,各温度处理的叶绿素a、b和类胡萝卜素含量出现先下降后上升的趋势,电导率基本呈上升的趋势,SOD活性、MDA含量基本呈先上升后降低的趋势。(2)在相同处理时间时,38℃/28℃、42℃/31℃两个高温处理下,叶绿素和类胡萝卜素含量相对较低;处理到了第10天,随着温度的升高电导率逐渐降低;随着处理温度的升高,植株SOD活性基本呈上升的趋势,MDA含量基本呈下降的趋势。(3)在42℃/31℃高温下,第5天植株叶片出现褐色斑点,38℃/28℃高温下,第25天植株叶片出现少量褐色斑点。结果表明马银花适合应用于我国东南及中南部省份的园林绿化。     

黄藤花粉低温贮藏初探

研究了贮藏温度、真空与常压以及化冻方式对黄藤花粉低温贮藏后生活力的影响.结果表明:贮藏天数增加,黄藤花粉生活力下降;贮藏温度越低,花粉生活力下降越缓慢;常温、0、-5、-20℃下真空贮藏比常压贮藏效果好,但-30℃和-40℃条件下两者间不存在显著差异;40℃水浴化冻与室温下缓慢复苏两者间没有显著差异.     

柔性气调库中CO2浓度对沾化冬枣果实品质和耐藏性的影响

以沾化冬枣为试材,研究了不同浓度CO2对冬枣果实品质及贮藏效果的影响。结果表明,在温度-1℃~-2℃,氧气3%~5%条件下,1.0%~1.5%的CO2浓度能有效抑制冬枣呼吸作用,减缓可溶性固形物的增加,减少维生素的损失,保持果实硬度,降低冬枣的失重率和腐烂率,保持贮藏品质,延长贮藏期。     

温度和处理方式对余甘子果理化性质影响

余甘子果实采收期长于多数水果,留树越冬落果率低,采后余甘子果实失重率、腐烂率高,容易发生褐变,所以果实的贮藏保鲜成为了余甘子加工行业的关键问题,试验选取包装、预处理方式以及贮藏温度对采后余甘子果进行贮藏工艺的研究。结果表明:冷激处理并且真空包装,贮藏温度为4℃条件下,余甘子果实的失重率为0,含水率保持在81.5%左右,贮藏时间达到70 d,理化性质变化较小,Vc和还原糖等营养成分得到较好保留,无胀袋现象,为余甘子果的贮藏提供理论参考。     

桃新品种‘保佳红’与‘早久保’果实生长发育及贮藏特性的对比研究

以河北省辛集市南智邱镇大车城村桃园9年生桃新品种‘保佳红’与‘早久保’为参试对象,测定分析了其果实生长发育过程中单果重、横纵侧径、总糖含量、可滴定酸含量等指标的动态变化以及贮藏过程中可溶性固形物含量、硬度和失重率的变化。结果表明,‘保佳红’果实生长动态与‘早久保’相似,单果重、横纵侧径增长均呈双“S”形曲线;在果实整个生长发育过程中,总糖含量呈上升趋势;可滴定酸含量呈现先上升后下降趋势;硬度在果实发育前期变化较小,至果实第二次快速生长阶段迅速下降;糖酸比逐渐增加。‘保佳红’比‘早久保’耐贮,常温下贮藏6天、0℃条件下贮藏27天仍保持固有风味。     

晚大新高砂梨臭氧保鲜试验研究

用臭氧气体、臭氧水对晚大新高砂梨进行处理,并在10℃条件下贮藏,研究其呼吸强度、POD活性、总糖、总酸和维生素C含量以及失重率和腐烂率的变化.结果表明:晚大新高砂梨用臭氧水处理能保持原有的品质和风味,降低呼吸强度,延缓其营养成分的损失,失重率和腐烂率显著低于对照组,延长贮藏期限.     

森林蔬菜黄藤笋的营养成分分析及评价

黄藤是我国特有的一种棕榈藤,它的藤茎嫩梢(藤笋)很早就被原产地居民所食用．分析评价了黄藤笋的营养成分,并与其它几类蔬菜进行了比较．结果显示:黄藤笋中的蛋白质含量高达20．2％,仅略低于绿叶菜类蔬菜(23．8％),高于葱蒜类(13．89％)、瓜类(17．82％)、根菜类(12．98％)、薯芋类(11．41％)蔬菜．脂肪含量为0．221％,低于上述几类藏菜．黄藤笋中含有丰富的矿质元素,其中钙含量最高(0．824％),其次为磷和镁,含量分别为0．547％和2780mg／kg．黄藤笋中含有17种氨基酸,总量为224．5mg／g,其中人体必需氨基酸8种,占氨基酸总量的52．69％．采用氨基酸比值系数法对黄藤笋中的蛋白质营养价值进行了评价,氨基酸比值系数分为75．23,营养价值优于韭菜(69．80)、菠菜(66．77)和苋菜(61．88)等常见蔬菜．     

NO对杨梅采后活性氧代谢和腐烂的影响

用0,10,25和50 μmol·L-1硝普钠(SNP)浸泡杨梅2 h,在(0±0.5)℃贮藏16天.贮藏期间每隔4天取样测定活性氧产量、相对电导率、MDA含量及相关酶类如SOD,CAT,POD的变化,最后统计腐烂指数.结果显示:25μmol·L-1 SNP释放的NO处理可降低杨梅果实的腐烂率,延缓Vc的降解,抑制贮藏前期可滴定酸的下降和总糖的变化,提高杨梅果实中SOD,CAT,POD保护酶的活性,抑制H2O2,O2-·含量的增加,降低MDA的含量和膜透性的升高,防止膜脂过氧化,延缓果实的衰老.适宜浓度的NO处理可维持杨梅采后活性氧代谢的平衡,从而延缓果实的衰老进程和抑制果实腐烂,保持杨梅良好的贮藏品质.     

贮藏温度和贮藏时间对垂柳种子生活力的影响

以成熟的垂柳种子为材料,测定了不同贮藏温度和不同贮藏时间下垂柳种子发芽率、发芽势、活力指数等生活力指标的变化,以探索贮藏温度和贮藏时间对垂柳种子生活力的影响。结果表明:适当的低温-10℃、-5℃、4℃可以延缓垂柳种子的劣变,延长其贮藏时间;常温20℃与极低温-20℃条件下会降低种子的生活力,表现为活力指数降低;随贮藏天数的增加,发芽率、发芽势、发芽指数表现出先升高后降低的趋势,发芽速则是先降低后升高。常温20℃贮藏7天种子发芽率显著下降,在-5℃贮藏3天的条件下种子生活力最强,可应用于垂柳种子萌发及人工种苗培育的实践中。     

Effects of storage conditions on dormancy and vigor of Picea abies seeds

The dormancy and vigor of Picea abies seeds were studied after five months of storage at 25 and 75% relative humidity (RH) and 5 and 12 °C. Dormancy was evaluated by studying germination response to light and moist chilling at 12 and 21 °C. Dormancy causing germination reduction in the dark was induced in seeds during storage at 25% RH (5–6% moisture content, MC) in darkness. The dormancy was greater when seeds were germinated at 12 than at 21 °C and after storage at 12 than at 5 °C. The effective dormancy relief by light indicates that germination was under phytochrome control. Moist chilling could partly replace light. According to accelerated aging and leachate conductivity tests, dry seeds could be stored at 12 °C for five months without affecting their vigor. After storage at 75% RH (11% MC) and 5 °C, the seeds germinated slowly and incompletely. The decreased germination response to light indicates that other processes than those mediated directly by phytochrome restricted germination of these seeds. The positive germination response to moist chilling suggested that secondary dormancy was induced in the seeds. However, vigor tests gave some evidence of simultaneous decrease of vigor. Storage at 75% RH and 12 °C decreased germination nearly to 0%. Germination of seeds stored at 75% RH could be stimulated by a short accelerated aging period.     

低温贮藏对白蛾黑基啮小蜂羽化及出蜂的影响

白蛾黑基啮小蜂(Tetrastichus nigricoxae Yang)在柞蚕(Antheraea pernyi Guerin-Meneville)蛹内分别发育至老熟幼虫期、预蛹期和蛹中期,再于5 ℃分别冷藏7,14,21 d后让其正常发育至羽化出蜂,测定低温贮藏对该寄生蜂羽化及出蜂的影响.结果表明白蛾黑基啮小蜂于5...     

黄藤笋和4种常见茎菜抗氧化活性的比较研究(英文)

以纯水和100%乙醇作为提取溶剂,采用超声波和50℃水浴萃取法获得了黄藤笋和4种常见茎类蔬菜(芦笋、茭白、莴笋和甜麻竹)的提取液,并通过DPPH法测定了这些提取液的总抗氧化活性(DPPH自由基清除率)。结果表明:黄藤笋提取液的抗氧化活性最强,其次是芦笋,甜麻竹提取液的抗氧化活性最低。黄藤笋、芦笋和莴笋乙醇提取液的抗氧化活性高于水提取液的抗氧化活性,而茭白和甜麻竹则相反。除甜麻竹外,其余4种茎菜提取液的抗氧化活性不因萃取方法的不同而有显著差异。研究还表明,黄藤笋提取液在稀释到3200倍时,DPPH自由基清除率仍有0.33%,而其他4种常见茎菜在稀释2～10倍后已丧失自由基清除能力。研究表明,黄藤笋作为保健品的添加剂具有很高的潜在利用价值。     

香水莲花花粉的采集、干燥和贮藏特性研究

【目的】研究香水莲花Nymphaea hybrid花粉活力和贮藏特性,以期为香水莲花有性繁殖和杂交育种的生产实践提供理论基础和技术指导。【方法】以黄、粉、紫3种不同花色的香水莲花品系为试材,采用花粉离体萌发培养基法测定不同开花天数(开花1、2、3、4、5 d)的香水莲花花粉活力、同一天不同时间段的香水莲花花粉活力、3个不同品系的香水莲花花粉活力、不同干燥方法(室内通风自然干燥、烘箱干燥和硅胶干燥)的香水莲花花粉活力及不同贮藏条件(室温、4、-20、-80℃)下贮藏不同时间(5、10、30、50、70、90、120、180 d)的香水莲花花粉活力。【结果】1)3种花色香水莲花的花粉活力均随开花时间呈现先升高后降低的变化规律,开花2 d的花粉活力最高;2)在一天7:30-17:30中,9:30-11:30的花粉活力较强;3)3个香水莲花品系间花粉活力存在差异,其中‘黄花型’香水莲花的花粉活力(60.61%)最高,‘紫花型’香水莲花的花粉活力(48.15%)最低;4)硅胶干燥法是香水莲花花粉干燥的最佳方式;5)4℃适于香水莲花花粉的短期贮藏,-20℃和-80℃适于香水莲花花粉的长期贮藏。【结论】在香水莲花开花2 d的9:30-11:30采集花粉,采用硅胶干燥法干燥后短期贮藏于4℃,长期贮藏于-20℃或-80℃条件下,可有效延长香水莲花花粉的寿命。     

Temporal variations in cold sensitivity of root growth in cold-stored white spruce seedlings

We examined effects of soil temperature on the number of roots produced by white spruce (Picea glauca (Moench.) Voss) seedlings during the first month of growth following 0-30 weeks of storage in darkness at -2 degrees C. After storage, seedlings were planted in pots and placed in a controlled-environment chamber with a constant air temperature of 11 degrees C and a 16-h photoperiod. Water baths were used to keep soil temperature at 3, 7 or 11 degrees C. The number of long roots (> 10 mm) produced was strongly dependent on soil temperature. At soil temperatures of 3 or 7 degrees C, the number of long roots produced was only 11 to 30% that at 11 degrees C. Seedlings that had been stored for 14 weeks and then planted in soil at 11 degrees C produced the greatest number of long roots. For seedlings planted in soil at 11 degrees C, the number of long roots increased with time of storage up to 14-18 weeks and then declined progressively with length of storage. No increase in number of long roots with length of storage up to 18 weeks was evident in seedlings planted in soil at 3 or 7 degrees C. The maximum number of short roots (5-10 mm) was observed in seedlings that had been stored for 17 weeks and then planted in soil at 7 or 11 degrees C.     

Assessment of frost damage to leafless stem tissues of Quercus petraea: A reappraisal of the method of relative conductivity

Leafless Quercus petraea stems 1.4–5.0 mm in diameterwere exposed to freezing temperatures before assessing frostdamage visually and by two methods where electrolyte leakagefrom tissues was examined. Visual assessment could not discriminatelethal from non-lethal damage, whereas electrolyte leakage could.Assessments based on the rate of electrolyte leakage took almosttwice as many man hours to obtain, but were more consistentthan those produced using the method of relative conductivity.Full equilibration of electrolyte leakage following exposureto freezing temperatures required at least 5 days at 4°C. Autoclaving the tissues at 121°C for 15 min failed to releaseall diffusible electrolytes even after 10 days equilibration,but complete release was achieved 24 h after autoclaving for120 min. Unless full equilibration is achieved, it is impossibleto define a value of relative conductivity that is indicativeof lethal damage. The use of predefined lethal values of relativeconductivity is inad visable because the relative conductivityof undamaged (unfrozen) shoots varies substantially with thephysiological state of the tissues. Allowing 5–7 days after freezing to permit full electrolyteequilibration, followed by autoclaving for 90–120 minat 121°C and allowing 24 h before measurement provides areliable method for assessing freezing injury by the methodof relative conductivity in small pieces of leafless stem tissues.Differences between treatments can then be assessed using standardstatistical procedures.     

Storability measures of Norway spruce and Scots pine seedlings and assessment of post-storage vitality by measuring shoot electrolyte leakage

As indoor frozen storage is increasing in forest tree nurseries it is important to have accurate methods for assessing seedling storability in autumn and methods to determine post-storage vitality. Storability of spruce (Picea abies (L.) Karst.) and pine (Pinus sylvestris L.) seedlings can be based on determination of dry matter content (DMC) of seedling shoots or by freezing shoots at –25°C and thereafter measure electrolyte leakage (SEL_diff–25). To compare these two methods we stored 1-year-old spruce and pine seedlings at different occasions during the autumn. To test if leakage of electrolytes from shoots (SEL) could indicate deteriorated vitality, we measured SEL at the end of storage. After storage seedling viability was determined in a three-week growth test, measuring shoot and root growth capacity (RGC). Determination of freezing tolerance (SEL_diff–25) before storage had a better ability to predict the outcome of storage compared to the DMC test. Measuring SEL at the end of the frozen storage period accurately indicated seedling vitality. Seedlings with SEL of 0–5% had a high survival rate whereas SEL over 10% indicated low survival and growth capacity after storage. The SEL method has a potential to become a screening test for identifying batches of seedlings that have been damaged during storage in the nursery.     

低温胁迫对我国北方地区引种的无花果抗寒性的影响

为给无花果抗寒能力的评价与抗寒品种的选育提供参考依据,以我国北方地区引种的14个无花果品种为研究对象,采用人工低温(0~-20℃)处理对其1年生枝条进行了胁迫试验,并对其相对电导率、可溶性蛋白含量、可溶性糖含量、脯氨酸含量、SOD活性、POD活性和MDA含量进行了测定,还根据相对电导率和对应的低温温度,依据logistic方程,建立了回归模型,对14个无花果品种的抗寒性进行了综合评价。结果表明:依据半致死温度来评价,布兰瑞克、ALMA等品种的抗寒性均较强,-5~-10℃的低温会严重影响参试的大部分品种的生存和生长发育;其SOD和可溶性糖在-10℃时的测定值是反映无花果抵抗和适应低温能力的一个临界值,而可溶性蛋白和POD的临界值是在处理温度为-5℃时的测定值。部分品种的综合抗寒能力的评价结果与其半致死温度的测定结果存在差异,但新早黄、ALMA、金傲芬和紫蕾等品种均具备较好的抗寒潜力。     

温度对橡胶树微型芽条培育的影响

以橡胶树优良品系云研73-477花药组培试管苗的茎尖、茎段和基部为外植体,进行不同温度条件下微型芽条培育的比较试验,结果表明:外植体在昼温28℃,夜温26℃的平均不定芽数在1.50个以上,萌生枝较健壮,枯顶较少,培养效果优于其他处理。     

山茶花粉生活力及贮藏条件初探

以山茶两种开放程度花朵（初开和盛开）的花粉为试材,采用无机酸法和联苯胺染色法研究了花朵开放程度和贮藏条件对花粉生活力的影响.结果表明：无机酸法不适于山茶花粉生活力的测定,联苯胺染色法能快速地检测山茶花粉的生活力.实验结果表明,两种花粉生活力随着贮藏时间的增加呈逐渐下降的趋势.花朵的开放程度对花粉的生活力影响不大,而贮藏条件对其影响显著：室温（13℃～25℃）下,两种山茶花粉贮藏12 d后生活力完全丧失;冷藏（2℃）条件下,盛开花粉贮藏26 d后生活力完全丧失,而初开花粉生活力完全丧失需要30 d.