Evaluation and improvement of post-harvest performance of cut Viburnum tinus inflorescence

Post-harvest performance of cut viburnum inflorescences was examined in the present study. Harvesting viburnum at three developmental stages resulted in significant differences on flower opening rate (FOR) and flower abscission rate (FAR), but not on vase life. Harvesting at Stage III (>50% open flowers) resulted in highest flower opening percentage, whereas harvesting at Stage I (10–30% open flowers) in significantly lower flower abscission percentage. Pulsing with 20 or 40 mg/l AgNO₃ for 24 h extended vase life by 1.6 and 1.9 days, respectively, compared to the controls. Furthermore, flower abscission was significantly reduced after 20 or 40 mg/l AgNO₃ treatments by 51 and 62%, respectively, compared to the controls. In contrast, vase solutions containing 100 mg/l DICA or 100 and 200 mg/l methanol did not extend vase life of cut viburnum inflorescences, but significantly reduced flower abscission. Vase solutions containing 1 or 2% (w/v) sucrose negatively affected vase life, flower opening and flower abscission of viburnum inflorescence. Post-harvest treatments with 1-MCP at 10 μl/l in an ethylene-free environment resulted in extension of vase life and in significant reduction of FAR and respiration rates compared to the controls. Vase life of 1-MCP treated inflorescences was increased by 4.2 days compared to the controls. FAR of 1-MCP treated inflorescences remained significantly lower from the second to the eighth day of the vase life period.     

Effects of Bio-Bor Fertilizer Applications on Fruit Yield,Antioxidant Enzyme Activity and Freeze Injury of Strawberry

Deficiency of Boron (B) is widespread in the many parts of region of Turkey. So, the effects of boron and plant growth promoting bacteria (Bio-B) on the fruit yield, antioxidant enzyme activity and plant freeze injury of strawberry cv. Fern were investigated under field conditions between 2013 and 2014. The experimental plot was a completely randomized design with 4 replicates. Control and Bio-B were used as fertilizer agent in the experiment. Bio-B fertilizer was applied in three methods as soil, foliar and soil + foliar application methods to strawberry plants. Data through 2 years showed that the use of Bio-B significantly increased fruit yield, antioxidant enzyme activity and decreased freeze injury of strawberry leaf. Soil + foliar applications of Bio-B fertilizer increased to fruit yield compared to the control by 55.91?%. However, foliar application of Bio-B fertilizer increased to catalase (CAT), peroxidase (POD), and superoxide dismutase (SOD) enzyme activity compared with the control treatment 41.86?%, 48.99?%, and 26.59?%, respectively and decreased freeze injury of strawberry leaves 27.41?%. Overall, the results of this study suggest that Bio-B fertilizer application have the potential to increase the yield, antioxidant enzyme activity and decreased freeze injury of strawberry plants under field conditions.     

Freeze Injure and Antioxidant Enzyme Activity of Grapevine (<Emphasis Type="Italic">Vitis Vinifera</Emphasis>) Under Bio-Boron Fertilizer Applications

This study was conducted to determine the effects of plant growth promoting bacteria (PGPR) and boron (Bio-B) on the plant freeze injury, antioxidant enzyme activity and fruit yield of grapevine cultivar. The experimental plot was a completely randomized design with 5 replicates. As a trial model Bio-B and control were used as fertilizer agent. Bio-B fertilizer has been applied in different ways as soil?+?foliar, soil and foliar application methods to grapevine plants. Data through 2 years trials results showed that the use of Bio-B significantly decreased freeze injury and increased antioxidant enzyme activity of grapevine leaf. The highest damage rate at control group occurred with ?20?^°C and 94.89% ratio. In the same temperature degree at grape plant, the damage ratio of the Bio-B application from soil decreased by 21.55%; the application from leaf by 25.53% and with the application from soil?+?leaf by 26.24%. In addition to this, compared with control, in the CAT, POD and SOD enzyme activities increases occurred with the ratios as 28.57%, 22.05% and 39.25%, respectively. Generally, as results of this study under field conditions, Bio-B fertilizer application decreased freeze injure and increased antioxidant enzyme activity of the grapevine plant.     

北京观赏植物的冬、春季冻害分析

在2009年11月至2010年4月期间,北京地区出现了异常低温.与2000～2008年同期相比,平均气温降低了2.6℃,日均温＜0℃天数的频率增加了9.6％.这样的极端低温导致北京市植物园观赏植物的严重冻害.2010年春、夏季对17种160余株树木进行了调查.结果表明:广玉兰、紫薇、毛泡桐和天目琼花受冻害最为严重；其次是雪松、白皮松和紫叶李.冬季低温的强度与持续时间、树木的产地与抗寒性能以及栽植的生境等是导致树木受冻害程度差异的主要原因.     

2004年冬成都市外来园林植物冻害调查及建议

作者2005年春调查了成都市外来园林植物冻害情况,发现：（1）外来园林植物受冻害影响较为普遍,41种植物在不同程度上受害;（2）冻害影响存在区域差异,郊区冻害比城区严重.分析了冻害原因,并对园林植物引种提出建议.     

不同形态氮素对盐胁迫下番茄细胞超微结构与光合作用的影响

研究了在150 mmol ? L-1 NaCl胁迫下含铵态氮、硝态氮和硝酸铵（氮素浓度均为3 mmol ? L-1）的营养液培养的番茄幼苗生长、细胞超微结构、根系活力和光合作用参数的变化。结果表明：NaCl胁迫下,硝态氮处理叶片细胞出现伤害现象,而硝酸铵处理未见明显变化。铵态氮处理细胞超微结构明显发生破坏性变化,盐胁迫下,其伤害加剧。NaCl处理下,不同氮素形态处理下的植株生物量和根系活力均显著下降,其中硝酸铵处理的植株生物量和根系活力维持最高。NaCl胁迫下3种氮素形态处理的植株净光合速率（Pn）和蒸腾速率（Tr）均显著下降,其中硝酸铵处理的Pn和Tr要明显高于其他氮素处理。NaCl胁迫下,硝态氮处理和硝酸铵处理的水分利用效率（WUE）和气孔限制值（Ls）均明显上升,而铵态氮处理显著降低。综上,盐胁迫下,硝酸铵处理下番茄幼苗可维持较好的细胞超微结构、根系活力和较高的光合作用,维持较高的生物量,从而维持较高的耐盐性。     

2020年山东省泰沂山区苹果春季冻害调研报告

调查了2020年4月份3次大风降温天气对山东泰沂山区苹果主产县的影响情况。结果表明,4月5日低温冻害明显,9~12日低温冻害不明显,20~23日低温使个别地区冻害程度加剧;4月5日5~7时局部地区气温降至-6.1℃,沂水和沂源的苹果冻害严重,蒙阴稍轻,泰安、新泰和肥城基本未发生冻害;低洼地、近水地果树冻害明显高于山坡地;枝条、叶片、花瓣冻害较轻,雄蕊花药、花丝和雌蕊子房冻害较重,中心花较重边花较轻,均以子房受冻明显。在发生冻害的区域,富士品种受冻害严重,金冠、嘎拉受冻害较轻;受冻害程度晚熟品种>中熟品种>早熟品种,普通型品种>短枝型品种。     

宁夏酿酒葡萄不同埋土方式越冬效果的比较

为探索北方传统埋土方式和其他不同埋土方式下葡萄根部及藤蔓部温度变化规律及其保温效果,对宁夏贺兰山东麓冬季酿酒葡萄不同埋土方式下保温性能进行对比研究。结果表明,1)土覆乙烯醋酸-乙烯酯(EVA)膜的保温效果最好,翌年葡萄品质、产量最佳,产量高出传统埋土方式30%。2)传统埋土方式下葡萄冻害依然存在,虽埋土带下根部受冻较轻,但埋土区域外的侧根严重受冻。3)土覆EVA膜为推荐使用的北方冬季埋土越冬方式,其他推荐的方式依次是土覆聚氯乙烯(PVC)膜、土覆聚乙烯(PE)膜、PVC膜覆土及沟埋。     

Growth and nutrient partitioning of containerized Cercis siliquastrum L. under two fertilizer regimes

Lebanon's native flora is threatened by loss of natural habitat to rural and urban development and the increased demand of plant materials for landscaping. Despite Lebanon's floristic richness, most taxa used for landscaping are non-native. This study was done to determine if Cercis siliquastrum (L.) is amenable to container production. Therefore, six open pollinated seeds sources native to Lebanon were grown under two fertilizer rates to study growth, N, P, K uptake efficiency, and partitioning. Two-year-old seedlings were planted in 11 L containers in a 3:1 pine bark:compost substrate. Seedlings within each seed source or mother tree were grown at either 25 or 100 mg N L⁻¹ from 21N–3.1P–5.9K water-soluble fertilizer. Seedlings of all sources grown under 25 mg N L⁻¹ had greater dry weight than those grown at 100 mg. Nutrient loading occurred in plants under the high fertilizer rate, although total plant N, P, and K content were not affected by fertilizer rate. There were significant differences in mineral nutrient uptake and nutrient use efficiencies among the seed sources. The results show that C. siliquastrum is amenable to container production. The great variation in growth rate and nutrient use efficiency among the limited number of seed sources studied suggest that significant improvement can be made through mother tree selection and/or clonal propagation of superior individual plants within a source.     

核桃树冻害发生原因及冻害预防对策

核桃已成为新疆叶城县农民家庭经济收入的重要来源。但核桃树低温冻害造成其巨大经济损失。现就核桃树冻害发生原因、预防对策及补救措施进行总结。     

5-氨基乙酰丙酸对弱光下甜瓜幼苗光合作用和抗冷性的促进效应

 5-氨基乙酰丙酸(ALA)10 mg·L 处理能够明显提高弱光下生长的甜瓜幼苗叶片净光合速率(Pn)，而低温胁迫明显降低甜瓜幼苗叶片光合能力。经ALA处理过的甜瓜幼苗光合表观量子效率、羧化效率、气孔开度、叶片叶绿素(特别是叶绿素b)和可溶性糖含量均显著增加。在ALA处理3 d之后将幼苗转移到8℃低温条件下4 h，对照叶片光合能力基本丧失，而ALA处理叶片仍能维持一定的光合能力，并在20 h内基本恢复至对照水平。若幼苗在低温下处理6 h，对照植株完全死亡，而ALA预处理植株仅出现少量伤害症状。本研究结果表明，ALA处理可以提高植物耐弱光性和抗冷性。     

中国猕猴桃主产区的冻害调查及其应对措施

2007～2011年对中国猕猴桃集中产业带的冻害情况进行了调查。结果表明:陕西关中中西部地区冻害发生具有普遍性和频繁性;"红阳"品种最重,"徐香"次之;冻害程度与树龄和树势有关,以初挂果果园和长势过旺的幼树发生比较严重,树冠上主要危害1 a生枝条,树干的受冻部位主要在地面以上至50 cm以下这个区段;应对措施包括园地选择和品种选择,提高嫁接部位,柴草包裹树干,控制生长,备根蘖苗进行桥接,减少花果量和枝叶量,材料包扎伤口等。     

番茄杂交及回交后代耐冷性分析

以番茄耐冷品系与冷敏感品系为亲本配制成杂种F1代、F2代、回交一代（BC1）及回交二代（BC2），以低温胁迫处理后的胚根生长抑制度和组织伤害率为指标对杂交及回交后代种子发芽期和植株开花期的耐冷性进行了鉴定。结果表明经耐冷性选择的F2与未经选择的F2相比耐冷性明显提高。在BC1群体中分别选择耐冷株和冷敏感株回交得到的BC2的耐冷性存在显著差异。     

茄子花药低温胁迫培养及耐冷性诱导

以 6个茄子品种为试材 ,在低温胁迫条件下进行花药培养。结果表明 5～ 6℃低温胁迫处理可诱导花药形成耐冷性愈伤组织 ,在MS +NAA(0 .0 2mg·L-1) +ZT(1.0mg·L-1)培养基上耐冷性愈伤组织的分化率达到31.6 % ,由耐冷性愈伤组织再生植株的低温伤害率明显低于原品种     

黄瓜霜冻与冰核活性细菌的关系

通过霜冻模拟试验,研究黄瓜霜冻与冰核活性(INA)细菌的关系。结果表明,黄瓜霜冻是细胞间水分结冰造成的伤害。发生霜冻有一个温度范围,在这个范围内不同温度下发生霜冻的机率接近对数正态分布。INA细菌是诱发黄瓜发生霜冻的重要因素,由于它的存在,黄瓜霜冻的叶温范围为-1.8～-7.0℃,而无菌叶为-4.8～-10.8℃。INA细菌的成冰活性越强、浓度越大,则发生霜冻的平均温度越高。叶片受害率与INA细菌的浓度和低温强度之间存在对数关系。通过降低INA细菌浓度或削弱其活性的方法将成为黄瓜防霜的一种新途径。特别是在细菌浓度大和低温强度逐渐减弱的春季,采用这种方法更为有效。     

贺兰山东麓六个酿酒葡萄品种抗寒性比较

以宁夏贺兰山东麓主栽的"赤霞珠""美乐""蛇龙珠""马瑟兰""西拉""霞多丽"6种酿酒葡萄发育良好的1年生枝条为试材,在4℃的对照及-18、-20、-22、-24℃的低温条件下模拟低温冻害,通过测定其电导率值、脯氨酸(Pro)含量、丙二醛(MDA)含量3项生理指标,以期鉴定贺兰山东麓大量种植的欧亚良种酿酒葡萄的抗寒性,提高贺兰山东麓葡萄产区的越冬冻害防御能力。结果表明:随着处理温度不断下降,6种酿酒葡萄品种中的枝条电解质渗出率增大;脯氨酸含量、丙二醛含量显著增加。6个试验品种的抗寒性强弱为"赤霞珠">"霞多丽">"蛇龙珠">"马瑟兰">"美乐">"西拉"。     

Regulation of K uptake, water uptake, and growth of tomato during K starvation and recovery

In order to analyze the dynamics of growth, water and K uptake, the effects of 1, 3 and 7 days of potassium starvation and the recovery capability during 7 days afterwards were investigated in vegetative tomato plants. After 7 days of K starvation, plant dry matter was reduced by 36% compared to control plants. After 3 days of starvation plants showed a 15% reduction in dry matter and a 25% reduction in growth rate (not statistically significant). K starvation reduced leaf area and specific leaf area (SLA) and it increased leaf dry matter percentage. K starvation enhanced dry matter partitioning into the roots at the expense of the stem. Plant K concentration was reduced by K starvation with the strongest effect in the leaves and roots. When a 3-day K starvation period was followed by 7 days of recovery with full strength nutrient solution, growth and plant K concentration completely recovered, but not after 7 days of K starvation. Xylem sap flow was reduced by K starvation and after 7 days of starvation the K concentration in the sap was reduced by 60%. During the starvation period, the reduction in relative growth rate was linearly related to the plant K concentration. The critical potassium concentration in the plant (the K concentration at which relative growth rate was reduced by 10%) was determined according to the nutrient interruption technique. The critical concentration was 4.3% K which was reached after 2.5 days of K starvation while the potassium concentration of control plants was 6.3%. During recovery the dry matter growth rate seemed to be the most important factor determining K uptake.     

抗菌肽基因Gnk2-1经花粉管通道法导入西瓜的初步研究

 通过花粉管通道介导银杏抗菌肽基因Gnk2-1 于西瓜自交系‘04-1-2’中，以浓度为100、200、 300 和400 ng · μL-1 的DNA 为供体，分别于授粉后24、27、30 和33 h 导入，对子代进行PCR 检测。结 果表明：T0 代坐果率和单瓜结籽数随授粉后处理时间的增加而升高，但在各个处理时间下均显著低于对 照；外源DNA 的导入对授粉后27 h 处理的T1 代种子发芽率和授粉后24 h 处理的T1 代种子出苗率均造成 显著降低；不同DNA 浓度转化的T1 代种子的发芽率和出苗率与对照相比差异不显著；对1 280 株T1 幼 苗进行PCR 检测，得到32 株阳性转化植株，总体转化率为2.5%，最佳转化时间为授粉后24 ~ 27 h，最佳 DNA 转化浓度为100 ~ 200 ng · μL-1；PCR 阳性植株抗病鉴定表明转基因植株对西瓜枯萎病的抗性有所增强。     

Influence of sub-optimal temperature on tomato growth and yield: a review

Summary

The effects of temperature on growth, development and yield of tomato (Lycopersicon esculentum) are reviewed with special emphasis on cultivar differences. The focus is on sub-optimal temperatures, above the level where chilling injury occurs. Temperature has a large effect on all aspects of development. Leaf and truss initiation rates decrease linearly with decreasing temperature. Although these rates may be different for different cultivars their response to temperature is the same. Young plants grown at sub-optimal temperatures produce thicker leaves, so they intercept less light and therefore have a lower relative growth rate. There was no interaction between temperature and cultivar for relative growth rate and related traits. In a crop producing fruits, this aspect is less important as most of the light is intercepted anyway. At sub-optimal temperatures, fruit set is reduced as a result of poorer pollen quality. The period between anthesis and ripening of the fruit increases and, as the growth rate of the fruit at a certain developmental stage is independent of temperature, fruits become larger at sub-optimal temperature. Higher temperature leads to an increase in early yield, at the cost of vegetative growth, but may also cause a delay in later trusses. Total yield over a whole season might be equal at lower temperatures, but higher tomato prices early in the season do not make it economically profitable to reduce the temperature in the greenhouse. Short-term effects might thus be different from long-term effects. In the literature, the link between yield and whole plant growth is often missing, limiting the possibilities of studying the underlying processes that contribute to changes in yield. Breeding for cultivars with equal production at lower temperatures is hampered by the limited variation for temperature response in cultivated tomato. Therefore breeders have to look for other sources of variation, as in related wild Lycopersicon species.     

利用叶绿素荧光预测水蜜桃果实冷害研究

采用叶绿素荧光技术检测冷藏条件下水蜜桃冷害发生进程中初始荧光（Fv）、最大荧光（Fm）、可变荧光（Fv = Fm/Fo）、光化学效率（Fv/Fm）等叶绿素荧光动力学参数的变化,分析了叶绿素荧光参数与果肉出汁率的相关性以及与呼吸作用的关系。研究结果发现,在冷藏过程中,叶绿素荧光参数都呈下降趋势,冷害发生以后,Fm和Fv/Fm下降速度加快,而中途加温处理能够缓解Fm和Fv/Fm降低。同时,Fm和Fv/Fm与果肉出汁率之间存在显著的正相关,利用测定Fm和Fv/Fm能够初步预测冷害的发生情况。