pH对马铃薯‘转心乌’块茎花色苷颜色变化及降解速率的影响

用分光光度法在体外研究了不同pH条件下马铃薯'转心乌'块茎花色苷颜色呈现和降解速率的变化,以探讨马铃薯'转心乌,块茎颜色呈现的机理.结果显示:在pH 2.0时,该花色苷呈现最强烈的红色.随着pH从0增加到13.0,该花色苷在可见光区的最大吸收波长(λvis max)依次出现红移、蓝移,然后消失,在可见光区的最大吸收波长处的吸光值(Aλ,vis max)呈现为一条单峰曲线,峰值在pH 2.0处.当原始pH值被恢复到2.0后,如果原始pH小于或等于5.0,花色苷的红色均被恢复得更浓烈,λvis max不同程度地趋向537 nm,Aλ,vis max增加;如果原始pH大于或等于6.0,花色苷的红色根本不能被恢复,λvis max几乎不变,Aλ,vis max仍然维持低水平.在15℃、黑暗中,该花色苷在pH 0～5.0条件下均随时间推移而降解,在pH 2.0时的降解速度最慢;当pH小于或等于3.0时,该花色苷总体上降解缓慢,而且降解过程基本符合一级反应动力学.研究表明,'转心乌'块茎花色苷在可见光区的吸收光谱和在15℃、黑暗中的降解速度均具pH依赖性.     

用马铃薯人工饲养马铃薯块茎蛾的方法

介绍一种马铃薯块茎蛾Phthorimaeaoperculella的室内人工饲养方法。在人工养虫室内用 1 0 %的蜂蜜水喂养成虫 ,用滤纸收集卵块 ,幼虫在薯块上饲养 ,化蛹于牛皮纸卷成的纸筒中 ,饲养结果发现马铃薯块茎蛾完成 1代大约需要 35～ 4 6d ,室内连续饲养块茎蛾 3代 ,卵的孵化率、幼虫化蛹率、成虫羽化率均在 90 %以上。     

马铃薯块茎蛾的交配行为

在温度为(24±2)℃、光周期为L∶D=14∶10、相对湿度为50%～70%环境条件下观察了马铃薯块茎蛾Phthorimaea operculella(Zeller)交配行为。结果表明,1～2日龄、3～4日龄成虫交配高峰期分别发生在进入暗期后的8.0～10.0h、6.5～8.0h内。两性交配率随日龄的增加显著下降。马铃薯块茎蛾雄成虫具有多次交配能力,在连续发生2次以上行为交配时会导致雄蛾有效交配率下降。雄蛾平均有效交配次数可达3.8次/头,最高达6次。增加雄性比例不会显著提高单雌产卵量,但将性比(♀:♂)由1∶1升至2∶1时即可显著降低单雌产卵量。     

马铃薯块茎中总RNA的快速提取

马铃薯块茎中由于含有大量的多糖和酚类物质,因此难以从中提取RNA。本实验采用CTAB法从马铃薯块茎中提取了总RNA,并进行了马铃薯病毒的检验。结果表明:得到的RNA完整性好,A260/A280在1.7～2.0范围内,纯度也比较高。用RT-PCR方法进行马铃薯Y病毒的检验,得到了一条与预计扩增长度相同的一条带,并检验出枣庄地区马铃薯Y病毒的感染率为75%。     

理化因子导致梅花'南京红'花色色素的颜色变化

梅花是中国的候选国花之一。属于花色苷的梅花'南京红'花色色素用含1％浓盐酸(v／v)的甲醇提取,并呈现纯净的紫红色。体外试验表明:该色素在pH0-3范围内颜色稳定,因不同光质、热、氧化剂、还原剂、螯合剂而呈现无色、墨绿色或黄绿色,因不同金属离子、离子的不同浓度而呈现程度不同的红色、紫色、黑黄色、红中带黑或微蓝绿色,葡萄糖和低浓度苯甲酸钠几乎不影响其色泽,蔗糖使颜色变淡,柠檬酸却使其颜色变深。该文可为梅花红色花色的机理探索、梅花花色苷的分子结构鉴定、梅花红色花色色素的开发利用提供参考和前提。     

光周期调节马铃薯块茎形成的分子机制

光周期调节马铃薯块茎形成的分子机制研究最近取得了很大进展.综合介绍了赤霉素(gibberellins,GAs)、马铃薯StCOL3(CONSTANS-LIKE3)基因和StFT(FLOWERING LOCUST)基因以及蔗糖运输载体(sucrose transporters,SUTs)在短日照调节马铃薯块茎形成中的作用.     

云南马铃薯地方彩色品种“剑川红”和“转心乌”的花色苷主成分分析

彩色马铃薯富含花色苷,是一种天然抗氧化食品.本研究采用高效液相色谱质谱联用技术以引进品种“黑美人”为对照分析了云南马铃薯地方特色品种“剑川红”和“转心乌”花色苷的主要成分.结果表明:“剑川红”色素主要为酰化天竺葵色素类花色苷,其主要成分为天竺葵素3-[ 6-O-( 4-O-E-p-香豆酰-O-α-吡喃鼠李糖苷)-β-D-吡喃葡萄糖苷]-5-O-β-D-毗喃葡萄糖苷.“转心乌”和“黑美人”所含色素相似,主要为酰化矮牵牛色索、锦葵色素、芍药色素类衍生物,主要成分均为矮牵牛花色素3-[ 6-O-( 4-O-E-p-香豆酰-O-α-吡喃鼠李糖苷)-β-D-毗喃葡萄糖苷]-5-O-β-D-毗喃葡萄糖苷.     

延迟交配对马铃薯块茎蛾繁殖的影响

[目的]为了明确延迟交配对马铃薯块茎蛾Phthorimaea operculella Zeller繁殖的影响.[方法]在室内条件下,设置雌雄延迟交配、雄虫延迟交配和雌虫延迟交配3种处理,观察延迟交配不同天数后马铃薯块茎蛾的交配率、交配持续时间、繁殖力和成虫寿命的变化情况.[结果]在3种延迟交配的情况下,延迟交配5d的交配率均是最低,且与雌虫延迟交配相比,雄虫延迟交配和雌雄虫延迟交配对交配率的影响更明显.延迟交配对卵孵化率和产卵量均有明显的不利影响,其中雌雄延迟交配、雄虫延迟交配、雌虫延迟交配三者的均在延迟交配2d时的产卵量最高,在延迟交配5d时的产卵量最低,且两性延迟交配、雌虫延迟交配之间有显著差异.此外,受到延迟交配的影响雌雄虫寿命均有所增加,并且与单一性别对寿命的影响而言,两性延迟交配对寿命的影响更为明显,与雌虫相比雄虫更容易受到延迟交配的影响.[结论]延迟交配会对马铃薯块茎蛾的繁殖有明显不利的影响,可以对迷向法对马铃薯块茎蛾防治提供一定的参考.     

氮、磷、钾肥配施对'红叶'南天竹叶片色素和 可溶性糖含量的影响及相关性分析

以2年生'红叶'南天竹(Nandina domestica'Hongye')盆栽苗为实验材料,根据L16(45)正交实验设计进行3因素(包括氮、磷和钾肥)4水平(N单株施用量分别为0.0、18.4、36.8和55.2 mg,P2O5单株施用量分别为0.0、14.4、28.8和43.2 mg,K2 O单株施用量分别为0.0、0.8、1.6和2.4 mg)施肥实验,对2015年11月5日至2016年1月20日期间各组叶片的光合色素(包括叶绿素a、叶绿素b、总叶绿素和类胡萝卜素)、花色素苷和可溶性糖含量进行了比较;在此基础上,对叶片色素和可溶性糖含量及各肥料单株施用量进行了Pearson相关性分析.结果表明:总体来看,各组的光合色素和可溶性糖含量显著高于对照(N、P2O5和K2O单株施用量均为0.0 mg)组,而花色素苷含量则显著低于对照组.其中,T14(N、P2O5和K2O单株施用量分别为55.2、14.4和1.6 mg)、T15(N、P2O5和K2O单株施用量分别为55.2、28.8和0.8 mg)和T16(N、P2O5和K2O单株施用量分别为55.2、43.2和0.0 mg)组的光合色素含量均较高,T2(N、P2O5和K2O单株施用量分别为0.0、14.4和0.8 mg)、T3(N、P2O5和K2O单株施用量分别为0.0、28.8和1.6 mg)和T4(N、P2O5和K2O单株施用量分别为0.0、43.2和2.4 mg)组的花色素苷含量均较高,T3和T4组的可溶性糖含量均较低.极差分析结果表明:N单株施用量对光合色素含量的影响最大,K2 O单株施用量的影响最小;N单株施用量对花色素苷和可溶性糖含量的影响最大,P2 O5单株施用量的影响最小.相关性分析结果表明:N单株施用量与各光合色素含量呈极显著正相关,与可溶性糖含量呈显著正相关,与花色素苷含量呈极显著负相关;而P2O5和K2O单株施用量与上述指标的相关性均不显著.各光合色素含量间存在极显著正相关,并与可溶性糖含量呈显著正相关,与花色素苷含量呈极显著负相关.此外,花色素苷含量与可溶性糖含量呈显著负相关.研究结果显示:高氮能够延长'红叶'南天竹的绿叶期,低氮能够促进其叶片呈现红色,因此,在园林栽培过程中应根据实际需要施肥.     

特异切割马铃薯纺锤形块茎类病毒负链的多价核酶的构建和体外活 …

根据锤头型核酶的作用模式,设计、合成并克隆了特异切割马铃薯纺锤形块茎类病毒（ＰＳＴＶｄ）负链ＲＮＡ不同区域位点的双价和三价锤头型核酶基因。通过体外转录,将ＰＳＴＶｄ负链ＲＮＡ分别与双价和三价核酶混合,３７℃温育２ｈ。结果表明,双价核酶和三价核酶均表现出较高的切割活性,其中双价核酶处理的切割产物的大小与理论值相符合。三价核酶虽表现出较高的切割活性,但只是其中一价核酶在起作用,讨论了二价和三价核酶的应     

Characterization of potato genotypes by chlorophyll fluorescence during plant aging in a Mediterranean environment

Field experiments were conducted in Sicily (south Italy) during two seasons to characterize by chlorophyll (Chl) fluorescence four genotypes (Spunta, Sieglinde, Daytona, and Ninfa) of potato (Solanum tuberosum L.) for off-season production during plant aging and to analyse the possible relation between Chl parameters and tuber yield. Chl fluorescence parameters [initial fluorescence (F₀), maximum fluorescence (F_m), F_v/F_m, time in which maximal fluorescence occurs (T_max)] gained from Kautsky kinetics and Chl content were measured weekly, from 5^th to 6^th leaf appearance to beginning of plant senescence in the first season and to full plant senescence in the second season. F₀ and F_v/F_m were the most reliable Chl fluorescence parameters for the definition of genotypic differences while Chl content and T_max were the most reliable Chl parameters to predict plant aging. Tuber yield was highly correlated with Chl content, T_max, F₀, and F_m.     

The hybridisation of somatically chromosome-doubled dihaploid potatoes with tetraploid cultivars and the use of doubled dihaploids in genetic analysis of Solatium tuberosum

Three doubled dihaploid potatoes were hybridised with six tetraploid cultivars and the offspring examined for commercially important characters. Doubled dihaploids used as parents did not reduce the within progeny phenotypic variation for most characters below that found in material produced by intercrossing heterozygous tetraploids. They could however prove useful for improving some characters in a breeding programme. The products of the hybridisations were used to examine the genetic control of discrete variables such as tuber skin pigmentation, tuber flesh colour, and skin russetting. Doubled dihaploids were found to be useful for such studies because they have only three out of the five possible tetraploid genotypes. Presence or absence of red tuber skin in the progenies of cv. Désirée was concluded to be due to the segregation of a dominant major gene which was simplex in the parental cultivar. The yellow flesh of Desiree was found to be recessive. On the hypothesis that russet skin was due to three complementary dominant genes, possible genotypes of the doubled dihaploids and cultivars could also be deduced.     

A review of the physiology of potato tuber dormancy

A review of the scientific literature relating to the physiology of potato (Solanum tuberosum) tuber dormancy is presented. Effort has been concentrated on an up-to-date overview of the current state of understanding, rather than comprehensively covering the very extensive literature going back over many decades. The format chosen follows the fate of the crop. After defining tuberisation and dormancy, the physiological activity of the dormant tuber is reviewed and the storage environment is considered from both a physical and chemical standpoint. Advances in chemical control and the potential for molecular biology are highlighted.     

Memristors: Memory elements in potato tubers

A memristor is a nonlinear element because its current-voltage characteristic is similar to that of a Lissajous pattern for nonlinear systems. This element was postulated recently and researchers are looking for it in different biosystems. We investigated electrical circuitry of red Irish potato tubers (Solanum tuberosum L.). The goal was to discover if potato tubers might have a new electrical component - a resistor with memory. The analysis was based on a cyclic current-voltage characteristic where the resistor with memory should manifest itself. We found that the electrostimulation by bipolar sinusoidal or triangle periodic waves induces electrical responses in the potato tubers with fingerprints of memristors. Tetraethylammonium chloride, an inhibitor of voltage gated K⁺ channels, transforms a memristor to a resistor in potato tubers. Our results demonstrate that a voltage gated K⁺ channel in the excitable tissue of potato tubers has properties of a memristor. Uncoupler carbonylcyanide-4-trifluoromethoxy-phenyl hydrazone decreases the amplitude of electrical responses at low and high frequencies of bipolar periodic sinusoidal or triangle electrostimulating waves. The discovery of memristors in plants creates a new direction in the understanding of electrical phenomena in plants.     

Effect of a granulovirus on mortality and dispersal of potato tuber worm (Lepidoptera: Gelechiidae) in refrigerated storage warehouse conditions

Potato tuber worm (PTW), Phthorimaea operculella (Zeller), is a world-wide pest of potato. In rustic stores, PTW larvae can infest 100% of stored tubers. Treatment of tubers in rustic stores with the PTW granulovirus (PoGV) has been demonstrated to protect stored tubers. This is the first study to show the effects of PoGV for protection of tubers stored in refrigerated warehouse conditions. Tubers were treated by dipping in aqueous suspensions of PoGV or water. An estimated 0.0819 larval equivalents of virus or 1.88×10⁹ viral occlusion bodies were deposited on each kilogram of tubers. They were held at 16°C for 11 days before lowering the temperature by 0.5°C per day until 10°C was reached. The tubers were stored at this temperature for 53 days. Mean numbers of infested tubers at the end of the assay was affected by both pre-infestation rate and virus treatment. Mean numbers of infested tubers in the control treatment was 3 tubers per chamber higher than in the virus treatment providing strong evidence that PoGV controlled larvae and minimized spread into un-infested tubers. Of the larvae that were retrieved in virus-treated infested tubers, the mean mortality was 87% compared to 37% in controls.     

Analysis of secreted protease inhibitors after water stress in potato tubers

Potato tubers (Solanum tuberosum) secrete two kinds of proteinase inhibitors after a water stress. The polypeptides have differing inhibitory activities but are Kunitz-type inhibitors based on amino-terminal sequences homologies. A proteolysis maturation type of a cell protease inhibitor was observed. They can constitute high MW complex, sometimes with another type of protein. The function of these protease inhibitors is discussed in relation to plant defence.