Molecular properties and activities of tuber proteins from starch potato cv. Kuras

Potato starch production leaves behind a huge amount of juice. This juice is rich in protein, which might be exploited for food, biotechnological, and pharmaceutical applications. In northern Europe cv. Kuras is dominant for industrial starch production, and juice protein of freshly harvested mature tubers was fractionated by Superdex 200 gel filtration. The fractions were subjected to selected activity assays (patatin, peroxidase, glyoxalases I and II, alpha-mannosidase, inhibition of trypsin, Fusarium protease, and alcalase) and protein subunit size determination by SDS-PAGE and mass spectrometry. Proteins present in SDS-PAGE bands were identified by tryptic peptide mass fingerprinting. Protein complexes such as ribosomes and proteasomes eluted with the void volume of the gel filtration. Large proteins were enzymes of starch synthesis dominated by starch phosphorylase L-1 (ca. 4% of total protein). Five identified dimeric patatin variants (25%) coeluted with four monomeric lipoxygenase variants (10%) at 97 kDa. Protease inhibitor I variants (4%) at 46 kDa (hexamer) inhibited alcalase. Fourteen Kunitz protease inhibitor variants (30%) at 19 kDa inhibited trypsin and Fusarium protease. Carboxypeptidase inhibitor variants (5%) and defensins (5%) coeluted with phenolics. The native sizes and molecular properties were determined for 43 different potato tuber proteins, several for the first time.     

Genetic manipulation for enhancing calcium content in potato tuber

Increased calcium (Ca) in potatoes may increase the production rate by enhancing tuber quality and storability. Additionally, increased Ca levels in important agricultural crops may help ameliorate the incidence of osteoporosis. However, the capacity to alter Ca levels in potato tubers through genetic manipulations has not been previously addressed. Here we demonstrate that potato tubers expressing the Arabidopsis H+/Ca2+ transporter sCAX1 (N-terminal autoinhibitory domain truncated version of CAtion eXchanger 1) contain up to 3-fold more Ca than wild-type tubers. The increased Ca appears to be distributed throughout the tuber. The sCAX1-expressing potatoes have normally undergone the tuber/plant/tuber cycle for three generations; the trait appeared stable through successive generations. The expression of sCAX1 does not appear to alter potato growth and development. Furthermore, increased Ca levels in sCAX1-expressing tubers do not appear to alter tuber morphology or yield. Given the preponderance of potato consumption worldwide, these transgenic plants may be a means of marginally increasing Ca intake levels in the population. To our knowledge, this study represents the first attempts to use biotechnology to increase the Ca content of potatoes.     

氮肥减量分施促进甘薯根系分化与块根膨大

【目的】研究减氮运筹对甘薯根系生长发育、块根分化建成的影响,并讨论其与产量形成的关系,为高产高效甘薯栽培提供理论和技术依据。【方法】2016年和2017年在安徽省农业科学院本部试验基地黄棕壤上以商薯19和徐薯22为供试材料进行盆栽试验。以常规习惯基施氮100 kg/hm2 (FP) 为对照,在减氮20%的条件下,设置3种氮肥施用方式:全部基施 (JS)、全部块根形成期 (移栽后35 d) 追施 (KS)、50%基施+50%块根形成期追施 (FS)。于移栽后35 d(块根分化建成后期)、80 d(块根膨大期) 和收获期挖根取样,调查不定根数、不定根根长、粗根和单株有效薯块的根径范围、根尖数、根表面积、根体积等,测定根系活力、地上部和根系生物量。【结果】与FP处理相比,JS处理降低了单薯重,使块根产量显著降低,KS处理显著增加了单株有效薯块数,使块根产量分别提高7.61%(商薯19) 和11.74%(徐薯22),FS处理提高了单株有效结薯数和单薯重,使块根产量分别增加22.10%(商薯19) 和21.37%(徐薯22)。同时,FS处理较FP处理增加了块根形成期和块根膨大期根系总长度、根系表面积、根系体积和根尖数目,增强了根系活力,提高了地上部、根系及有效薯块干重和根系/地上部干重比值。相关分析表明,块根膨大期甘薯根系形态特征参数均与单薯重和产量呈显著或者极显著正相关。【结论】将施氮量由100 kg/hm2减至80 kg/hm2,并将其中一半氮肥在块根形成期追施,可有效促进甘薯根系生长和有效薯块的早期形成,保证单株结薯数,同时还可维持生育后期较高的根系活力,提高块根膨大期生物量和分配比例,有利于薯块的膨大和产量的增加。     

Relative abundance and inhibitory distribution of protease inhibitors in potato juice from cv. Elkana.

Protease inhibitors from potato juice of cv. Elkana were purified and quantified. The protease inhibitors represent ca. 50% of the total soluble proteins in potato juice. The protease inhibitors were classified into seven different families: potato inhibitor I (PI-1), potato inhibitor II (PI-2), potato cysteine protease inhibitor (PCPI), potato aspartate protease inhibitor (PAPI), potato Kunitz-type protease inhibitor (PKPI), potato carboxypeptidase inhibitor (PCI), and "other serine protease inhibitors". The most abundant families were the PI-2 and PCPI families, representing 22 and 12% of all proteins in potato juice, respectively. Potato protease inhibitors show a broad spectrum of enzyme inhibition. All the families (except PCI) inhibited trypsin and/or chymotrypsin. PI-2 isoforms exhibit 82 and 50% of the total trypsin and chymotrypsin inhibiting activity, respectively. A strong variation within the latter activities was shown within one family and between protease inhibitor families.     

Increase in lipid content in potato tubers modified by 14-3-3 gene overexpression

Recently, transgenic potato plants were created with overexpression of the 14-3-3 protein derived from Cucurbita pepo. Detailed analysis of those plants suggested that the function of the isolated 14-3-3 isoform is in the control of carbohydrate and lipid metabolism in the plants. 14-3-3 protein overexpression gave rise to an increase in soluble sugar and catecholamine contents in both leaves and tubers. It is proposed that 14-3-3 protein affects carbohydrate metabolism in potato plants via regulation of catecholamine synthesis. Furthermore, genetically modified potato tubers with 14-3-3 protein overexpression showed changes in lipid content and composition. The transgenic potato tubers contained 69% more total fat compared to the wild-type plant. Separation of tuber lipids into polar and nonpolar fractions revealed that the transgenic potato tubers contained almost 3 times more nonpolar lipids than the control. Analysis of fatty acid composition, conducted by the means of gas chromatography, showed that linoleic acid was the main fatty acid present in the tubers of both modified and control potato plants. In the nonpolar fraction of the fat of the transgenic tubers the unsaturated fatty acids exhibited a higher participation in the sum of all fatty acids.     

Optimizing crop geometry for processing-grade tuber yield,quality and economics of potato in Grey Terrace Soil

Crop geometry has great influence on economically important characteristics such as total yield, processing-grade yield, tuber size distribution and tuber quality in Grey Terrace Soil. An experiment was conducted to develop a suitable crop geometry for the production of higher processing-grade yield and quality of potato tubers. The treatment consisted of three levels of inter-row spacing (60, 67.5 and 75 cm) and four levels of intra-row spacing (20, 25, 30 and 35 cm). Crop geometry significantly influenced growth, yield contributing characters, tuber size distribution and yield of potato. The highest chips, French fry grade tubers and total potato tuber yield were found in 67.5 cm × 25 cm crop geometry without affecting processing quality but all were in the highly acceptable range. Intra-row spacing of 25 cm produced the maximum processing quality tubers, closely followed by 30 cm. The highest gross and net returns with a benefit–cost ratio of 1.75 were recorded in 67.5 cm × 25 cm crop geometry. Therefore, the 67.5 cm × 25 cm crop geometry can be recommended for higher potato tuber yield and processing-grade tubers as well as higher economic return.     

patatin启动子调控烟草液泡转化酶抑制子在马铃薯抗低温糖化中的作用

为了降低马铃薯(Solanum tuberosum )块茎低温贮藏下还原糖的积累，实验构建了马铃薯块茎特异性启动子（CIPP）调控的烟草液泡转化酶抑制子Nt-VIF基因表达载体pBICNI，并转化马铃薯植株。PCR、Northern杂交和Southern杂交分析结果显示，CIPP调控的Nt-VIF基因全长cDNA成功地导入鄂马铃薯3号（E-3）植株。14个转基因株系块茎分别贮藏在4℃和20℃条件下，贮藏1个月后进行还原糖含量和液泡酸性转化酶（VI）活性测定。结果表明，在20℃条件下转基因株系块茎还原糖（RS）含量与对照相比差异不明显，在4℃条件下RS含量则显著下降，与对照相比下降幅度从34%（株系B-13）至76.8%（株系B-1），说明Nt-VIF cDNA在马铃薯中的表达，成功地抑制了液泡酸性转化酶的活性，导致还原糖含量降低。进一步分析表明，转基因块茎低温贮藏其液泡转化酶活性与还原糖含量呈显著的正直线相关（VI = 0.3084RS + 0.0673）。实验获得的B-1、B-2、B-6、B-9、B-14等5个转基因株系，块茎低温贮藏后能直接满足炸片加工对还原糖含量的要求。     

钾肥基施利于甘薯块根产量的形成

【目的】 研究不同施钾方法对甘薯块根产量形成的影响,可为甘薯高产稳产寻找合理的钾肥施用方法,并阐明其增产机理。【方法】 选取典型的食用型甘薯品种红香蕉和北京553为试材,于2013~2014年两个生长季在山东农业大学农学试验站进行田间试验。设4个施钾处理:不施钾肥（CK）、全部钾肥基施（JS）、全部钾肥封垄期追施（FS）、基施钾肥和封垄期追施钾肥各占50%（1/₂ JS+1/₂ FS）。在主茎第4、5片展开叶上标记13CO₂,24、48和96 h后取样,用质谱仪（Isoprime 100）测定不同部位的13C含量。从甘薯栽秧后50 d开始,每隔20 d取样直到收获。按根、茎、叶、柄四部分分别称重,将主茎自功能叶所在位置至基部等分为三段,取上、下两端用于测定蔗糖含量。收获期测定生物产量和块根产量,计算经济系数。【结果】 甘薯施用钾肥能显著提高生物产量、经济系数和块根产量,增产21.33%~34.38%。各施钾处理之间比较,生物产量差异不显著,经济系数和块根产量差异显著,其中基施钾肥处理的经济系数和块根产量最高。栽秧后50 d,基施钾肥处理植株干物质积累量和功能叶光合产物在块根中的分配率都显著高于其他施钾处理。栽秧后50 d和110 d,基施钾肥处理光合产物源端装载和库端卸载的效率显著高于其他处理,栽秧后150 d,所有施钾肥处理趋于一致。栽秧后50 d,基施钾肥处理光合产物转运效率显著高于其他施钾处理,栽秧后100 d和150 d,施钾肥处理间效果趋于一致。在栽秧后50~130 d,基施钾肥处理的块根膨大速率一直高于其他施钾处理。【结论】 在相同供试土壤和气候条件下,钾肥施用时间越早,越有利于甘薯早发、快长,促进块根早形成、快膨大;光合产物由叶片向块根运转效率的高值持续期越长,越有利于提高光合产物在块根中的分配。因此,全部钾肥基施甘薯经济系数和块根产量最高,是最经济有效的施肥方法。     

采后UV-C辐照对马铃薯干腐病的抑制效应及相关酶活性的影响

为探讨不同辐照剂量的短波紫外线(UV-C)处理对马铃薯干腐病的抑制作用及相关酶活性的影响,以贮藏期间的马铃薯块茎为材料,经剂量为0、5、15、25、35、45 kJ·m-2的UV-C辐照,研究分析经损伤接菌后马铃薯块茎干腐病病斑及相关防御性酶[过氧化氢酶(CAT)、过氧化物酶(POD)、苯丙氨酸解氨酶(PAL)、丙二醛(MDA)]的变化情况。结果表明,损伤接菌后的马铃薯块茎,经剂量5~45 kJ·m~(-2)的UV-C辐照处理,块茎中MDA、PAL活性均显著降低,POD活性显著升高;剂量5 kJ·m~(-2)的辐照处理可显著提高损伤接菌后的马铃薯块茎中CAT活性;剂量5~45 kJ·m~(-2)的辐照处理均可有效抑制马铃薯块茎病斑直径的扩散,其中以35 kJ·m~(-2)处理效果最佳。本研究证实UV-C辐照有助于提高贮藏期间马铃薯块茎对于干腐病的抗性,为利用UV-C这种新型环保的马铃薯贮藏方法提供了理论参考。     

4UFD-1400型马铃薯联合收获机改进设计与试验

针对4UFD-1400型马铃薯联合收获机田间收获试验中存在的传动速度偏高,输送系统易对薯块表皮造成擦伤,薯块输送和分级装袋自然流动不畅,有滞留堆积现象等问题,对该机传动系统、薯块输送系统进行了改进设计,并在平播旱地和全覆膜双垄播旱地进行了马铃薯收获试验。试验结果表明,改进机型土薯分离、薯秧分离、薯块输送、分级装袋等各部分的工作更协调、平稳、可靠,对全膜双垄播旱地和平播旱地马铃薯收获的质量和适应性好,对薯秧、杂草、地膜的分离能力强,可在不清除地膜、薯秧和杂草的条件下不缠绕、不堵塞地顺利作业;损失率、伤薯率、破皮率和含杂率分别低于0.8%、1.8%、2.9%和1.2%,较改进前显著降低,符合国家农业行业标准《NYT 1130-2006马铃薯收获机械》的规定;整机结构更紧凑,机组机动性更好,适用于土质松软、无板结的旱地(覆膜)种植马铃薯收获作业。     

Einfluß des Calcium-Angebotes auf Wachstumsrate und Calcium-Gehalt von Kartoffelknollen

Effect of calcium supply on growth rate and calcium content of potato tubers. . Using potato plants in water culture with a constant calcium supply to the roots, a study was made of the influence of additional supply of calcium to the tuber surface on growth rate and calcium content of the tubers. Under conditions of high relative humidity around the tubers the calcium nutrition of the tubers was exclusively dependent on the calcium supplied to the tuber surface (?exogenous calcium”?). With a high level of exogenous Ca the growth rate of the tubers was high and the rate of uptake of Ca was proportional to the tuber growth. With a low level of exogenous Ca the growth rate declined to a lower but constant value. In absence of exogenous supply of Ca the growth rate of the tubers declined gradually until growth ceased. Cessation of tuber growth occurred when the Ca content decreased below 0,36 mg Ca per g dry matter for smaller tubers and below 0,14 mg Ca per g dry matter for larger tubers. Severe Ca deficiency in potato tubers causes necrosis at the tuber apex.     

Cultivation of transgenic cyanophycin-producing potatoes does not negatively affect growth,reproduction and activity of the earthworm Lumbricus terrestris (L.)

A microcosm experiment was performed to investigate the effects of post-harvest potato tubers from transgenic cyanophycin-producing potatoes on Lumbricus terrestris (L.) activity and biomass, number of cocoons and their hatchability as well as the remaining cyanophycin content in soil and cast samples during a period of 80 days. Potato tubers from four transgenic potato events with different cyanophycin content in a range from 0.8 to 7.5% were compared to the near isogenic, non-transgenic control (Solanum tuberosum L. cv. Albatros) and a comparative potato cultivar (S. tuberosum L. cv. Désirée). One treatment with transgenic tuber residue but without earthworms was prepared as an additional control. Potato tuber loss from the surface of the microcosms was significantly higher in the treatments with transgenic potato tubers compared with non-transgenic treatments. It can be estimated that the earthworm contribution to potato tuber loss from the soil surface was approximately 61%. Mean number of cocoons in addition to the number of hatched cocoons varied from 2.6 to 6.2 and from 7 to 15 accounting for 45.2–83.35% hatchability, respectively, but no significant differences between the treatments were found. The same was true for the development of earthworm biomass in the various treatments. The cyanophycin content in soil samples was significantly higher when earthworms were present indicating that the cyanophycin content in the upper soil layer might have been enhanced through earthworm burrowing activity. Overall, it is concluded that tubers from transgenic cyanophycin potatoes are easily degradable and neither inhibit nor stimulate earthworm growth, reproduction, and activity.     

Characterization of the major proteins of tubers of yam bean (Pachyrhizus ahipa)

Tubers of six accessions of ahipa (Pachyrhizus ahipa) contained between 0.77 and 1.34% nitrogen on a dry weight basis. This corresponds to 4.8 to 8.4% crude protein based on a nitrogen to protein conversion factor of 6.25; but detailed analysis of AC230 showed that although 93% of the total N was extracted with buffer containing 1.0 M NaCl, about a third of this was lost on dialysis. It was calculated, therefore, that salt-soluble proteins comprise about 60% of the total tuber nitrogen, with low-molecular-mass nitrogenous components comprising a further 30%. Electophoretic analysis of the salt-soluble proteins showed similar patterns of components in the six accessions, with none being present in amounts sufficiently high to suggest a role as storage proteins. Furthermore, light microscopy failed to show significant deposits of protein within the tuber cells. Five "major" protein bands, which together accounted for about 19% of the total salt-soluble protein fraction were purified and subjected to N-terminal amino acid sequencing. Comparison of these with sequences in protein databases revealed similarities to alpha-amylases, chitinases and chitin binding proteins, cysteine proteinases (including major components from P. erosus tubers), a tuberization-specific protein from potato, and proteins induced in soybean and pea by stress or the plant hormone abscisic acid, respectively. It was concluded that the primary roles of these proteins are probably in aspects of tuber metabolism and development and/or conferring protection to pests and pathogens, and that true storage proteins are not present. The absence of storage proteins is consistent with the biological role of the tubers as storage organs for carbohydrates (cf cassava tuberous roots) rather than as propagules (cf yam and potato tubers).     

Soil and tuber calcium affecting tuber quality of processing potato (Solanum tuberosum L.) cultivars grown in Hokkaido,Japan

Calcium (Ca) nutrition for potato (Solanum tuberosum L.) is important to increase tuber Ca concentration and improve potato tuber yield and quality. High tuber Ca content among other benefits mitigates incidence of blackspot bruise through maintenance of membrane health and regulation of biochemical reactions that leads to potato tuber discoloration. However, growers avoid application of Ca fertilizer in potato production in the belief that it causes potato common scab in Hokkaido, Japan. This study was conducted in Hokkaido to determine the current status of soil Ca and tuber Ca content levels, and its effect in mitigating incidence of potato bruise. Soil and tuber samples were collected from 90 and 80 fields in Tokachi and Kamikawa districts, respectively, in 2013 and 2014. Soil samples were analyzed for base saturation, Ca saturation, and exchangeable Al. Tuber Ca content and susceptibility of tubers to bruising were also evaluated. This study found that (1) 81% and 76% of soils collected from Tokachi and Kamikawa district, respectively, were deficient in Ca level, (2) tuber Ca content was lower than the reported value (250 mg kg^?1) considered to mitigate incidence of bruise, and (3) incidence of bruise were influenced by both tuber specific gravity and Ca content. There is urgent need to apply Ca fertilizer to attain increased soil Ca levels and improve quality of tubers.     

Nitrates content in table potato tubers under the influence of herbicides and biostimulants

The objective of the study was to determine the effect of herbicides and biostimulants on the potato tuber content of nitrates. The experimental material consisted of tubers harvested in a field experiment which examined the following factors: three medium early potato cultivars (Bartek, Gawin, Honorata) and five methods of herbicide and biostimulant application (Harrier 295 ZC (linuron?+?chlomazon), Sencor 70 WG (metribuzin), growth regulator Kelpak SL (algae extract from Ecklonia maxima ? auxins and gibberellins), growth regulator Asahi SL (sodium para-nitrophenol, sodium ortho-nitrophenol, sodium 5-nitroguaiacol) and a control unit where weeds were mechanically controlled). The tuber content of nitrates was determined in fresh matter with an ion-selective nitrate electrode and silver–silver chloride reference electrode. Herbicides and biostimulants increased the potato tuber content of nitrates compared with control tubers. However, they did not pose a threat to consumer health. Tubers of plants sprayed with the herbicide Sencor 70 WG (metribuzin) and the biostimulant Asahi SL (sodium para-nitrophenol, sodium ortho-nitrophenol, sodium 5-nitroguaiacol) contained the most nitrates whose accumulation was also affected by cultivars and weather conditions in the study years.     

收获期马铃薯块茎碰撞恢复系数测定与影响因素分析

为了建立马铃薯块茎在土薯分离机构和振动筛上发生碰撞时的碰撞模型,该文基于质点对固定面的碰撞动力学理论在自制测定装置上对马铃薯块茎碰撞恢复系数进行了试验测定。对块茎碰撞恢复系数的主要影响因素碰撞材料、下落高度、块茎质量、含水率、跌落方向和马铃薯品种等进行了混合正交试验和单因素试验。混合正交试验结果表明,各因素对马铃薯块茎碰撞恢复系数的影响顺序为:碰撞材料、下落高度、块茎质量、含水率、跌落方向和马铃薯品种,其中碰撞材料、下落高度、块茎质量和含水率影响较为显著。单因素试验结果表明,马铃薯与65Mn钢、橡胶、马铃薯和土块间块茎碰撞恢复系数依次减小,其中新大坪的值分别为0.791 2、0.710 5、0.663 2、0.525 3,陇薯7号的值分别为0.762 7、0.695 2、0.690 4、0.563 1;马铃薯块茎碰撞恢复系数随着下落高度、块茎质量和含水率的增加而减小,回归方程决定系数均大于0.9。研究结果可为马铃薯收获机挖掘及土薯分离装置关键部件的优化设计提供参考。     

马铃薯专用中耕培土犁的应用及增产效果

中耕培土是马铃薯生产的关键耕作技术,影响马铃薯的产量和品质。传统的中耕培土犁培土效果达不到当前生产作业要求,限制了马铃薯产业发展。为解决该问题,该研究根据马铃薯生产现状,应用自主研发马铃薯专用中耕培土犁,并以传统中耕培土犁为对照,开展不同垄距培土犁培土效果对比试验,设置垄距为65、70、80和90 cm,分别在马铃薯苗期及现蕾期进行2次培土,探讨马铃薯专用培土犁的最佳培土模式。研究结果表明:应用马铃薯专用中耕培土犁培土,垄体明显增大,垄体土壤质量高于对照21.7%~33.4%,有利于马铃薯生育期地下干物质的积累,提高马铃薯匍匐茎数;有利于地下薯块的增长,大、中薯块茎产量增加,小薯块茎所占比率有所减少;马铃薯产量两年平均为38 215.0~43 131.2 kg/hm~2,比对照提高1.1%~7.3%,商品薯产量为33 788.9~39 346.7 kg/hm~2,比对照提高4.1%~11.2%,青薯产量为670.7~834.3 kg/hm~2,比对照降低18.7%~28.8%;其中垄距为80 cm培土处理马铃薯产量最高、青薯产量最低,均值分别为43 131.2和670.7 kg/hm~2,为马铃薯专用中耕培犁的最佳培土模式。该研究可为马铃薯生产提供指导。     

Effects of pH and heat treatments on the structure and solubility of potato proteins in different preparations

The soluble potato proteins are mainly composed of patatin and protease inhibitors. Using DSC and both far-UV and near-UV CD spectroscopy, it was shown that potato proteins unfold between 55 and 75 degrees C. Increasing the ionic strength from 15 to 200 mM generally caused an increase in denaturation temperature. It was concluded that either the dimeric protein patatin unfolds in its monomeric state or its monomers are loosely associated and unfold independently. Thermal unfolding of the protease inhibitors was correlated with a decrease in protease inhibitor activities and resulted in an ionic strength dependent loss of protein solubility. Potato proteins were soluble at neutral and strongly acidic pH values. The tertiary structure of patatin was irreversibly altered by precipitation at pH 5. At mildly acidic pH the overall potato protein solubility was dependent on ionic strength and the presence of unfolded patatin.     

钙水平对马铃薯试管薯产量、质量和生理病害的影响

利用MS培养液研究了不同浓度氯化钙对马铃薯试管薯的产量、 质量、 薯内钙含量及生理病害的影响。结果表明,MS培养液中不添加钙时,试管薯的结薯数量、 薯重及大薯率大幅度降低,没有＞100 mg 的试管薯,薯表面出现明显的黄褐色粗糙斑块,个别薯块现水浸状腐烂,腐烂率2.21%。薯内干物质、 淀粉、 可溶性糖和蛋白质含量也较正常钙用量下分别降低了36.8%、 41.39%、 10.7%.和.39.43%,丙二醛含量上升。4℃下贮藏6个月,薯皮失水皱缩严重,平均病害率达53.77%;室温下放置3周,发芽率25.53%,芽生长缓慢;MS 培养液中添加不同浓度的氯化钙,茎段结薯数和薯重随钙浓度的增加呈先增加后降低的变化趋势,大薯率和薯皮表面光泽度呈上升趋势,与正常钙水平相比,薯重增加了2.7%~47.86%、 结薯数增加了-11.49%~22.64%、 大薯率14.43%~26.08%。薯内干物质、 淀粉、 可溶性糖和蛋白质含量的变化均随钙浓度的增加呈先上升后下降的趋势,并较正常钙用量下增加了4.43%~8.62%（干物质）、 6.79%~16.49%（淀粉）、 3.89%~6.31%（可溶性糖）和 4.63%~8.29%（蛋白质）。薯内钙含量大幅度上升,平均值为177~267 g/g（最高值为9 mmol/L处理）,薯皮光滑无水浸状腐烂。4℃下贮藏6个月,薯皮正常,生理病害率随薯内钙含量升高呈下降趋势,病害率为1%~8.9%,决定系数R2=0.3812,且试管薯芽的萌发和生长能力正常。确定MS培养液中添加 9 mmol/L CaCl2是新大坪品种试管薯数量和质量的最优处理。