Evaluation of Potato Hybrids Obtained from Tetraploid-Diploid Crosses I. Parent-Offspring Relationships

A total of 45 tetraploid-diploid (4x—2x) hybrid progenies were obtained by crossing each of ten diploid parents as males to each of five tetraploid parents. A relatively low degree of determination (R²) of both 4x and 2x parents on the performance of their 4x—2x hybrid progenies was found for all six traits studied. This implies that test crossing and subsequent progeny analysis is necessary before such parents can be used in a breeding program. Since marketable yield was found to have a higher predictability than total yield, it is the preferred yield trait to be measured. Diploids which produce 2n gametes via FDR usually give rise to 4x progenies with a greater amount of heterosis than similar progenies derived from diploids which produce 2n gametes via SDR, although such heterosis is not necessarily expressed in terms of marketable yield.     

叶面喷施MnSO4对马铃薯植株叶片生理特性和块茎品质的影响

锰是马铃薯生长发育不可缺少的微量元素之一,本试验以‘青薯9号’为供试品种,设置了0(CK)、0.05%(T1)、0.1%(T2)、0.6%(T3)、1.1%(T4)5个MnSO₄浓度处理,对马铃薯幼苗期至块茎形成期进行叶面喷施,研究锰素对马铃薯叶片生理特性以及块茎贮藏期品质变化的影响。结果表明,过氧化物酶(peroxidase,POD)、氧化物歧化酶(oxide dismutase,SOD)、过氧化氢酶(catalase,CAT)活性随着喷施MnSO₄浓度的增加呈先升高后降低的趋势,其中喷施浓度为0.05%~0.1%MnSO₄可显著提高马铃薯叶片的POD活性,浓度为0.1%MnSO₄促进SOD、CAT活性的提高。喷施浓度为1.1%MnSO₄有利于块茎形成期根系活力(TTC还原量)的提高。就马铃薯块茎品质而言,喷施浓度为0.1%~0.6%MnSO₄可有效提高马铃薯块茎可溶性蛋白、有机酸、Vc、淀粉含量,且有利于减少贮藏期其各品质的流失;而喷施MnSO₄对块茎有机酸含量影响较小。由此表明,喷施0.1%~0.6%的MnSO₄可提高马铃薯植株叶片生理特性,并优化马铃薯品质。     

蔗糖对不同基因型马铃薯试管苗生长和长期保存的影响

研究不同蔗糖浓度对四个基因型马铃薯试管苗生长和长期保存的影响,为培育马铃薯健壮试管苗和长期保存马铃薯种质资源提供理论依据。以‘大西洋’、‘夏波蒂’、‘克新一号’和‘费乌瑞它’四个不同基因型马铃薯脱毒试管苗为试验材料,测定在不同蔗糖浓度下及经长期保存后恢复生长的马铃薯试管苗相关生理指标。结果表明:随着蔗糖处理浓度的增加,四个基因型马铃薯株高、有效节位数及腋芽萌发率均出现先增加后降低的生长趋势,当蔗糖浓度达到3%～4%时,除‘克新一号’外其余三个基因型均达到了最大值,6%的蔗糖浓度对‘大西洋’、‘夏波蒂’和‘费乌瑞它’的生长有明显的抑制作用;3%～6%的蔗糖浓度均能有效促进‘克新一号’的正常生长,8%的蔗糖浓度对其生长有显著的抑制作用;同时随着蔗糖浓度的增加均能有效延长四个基因型马铃薯试管苗的保存时间,当蔗糖浓度达到10%时,经保存一年均能达到90%以上的存活率,随着保存时间的延长其存活率又会有所下降。因此,3%的蔗糖浓度适合于‘大西洋’、‘夏波蒂’和‘费乌瑞它’基础苗扩繁,4%的蔗糖可作为三个基因型的壮苗培养基;4%的蔗糖浓度可同时作为‘克新一号’的扩繁和下地培养基;10%的蔗糖浓度可将四个基因型马铃薯脱毒试管苗的保存时间延长至1年,存活率均可达到90%以上,且长期保存后对试管苗继代生长无影响。本研究通过系统研究蔗糖对马铃薯试管苗生长和长期保存的影响,既有助于降低马铃薯试管苗工厂化生产成本,同时还可规避传统保存法造成的耗时耗工、种质资源易丢失等弊端,降低以植物生长抑制剂保存马铃薯种质造成的成活率低、变异率高等不安全因素。     

VDAL、Harpin拌种对马铃薯生长发育的影响

马铃薯采用种薯切块播种,拌种十分必要,但现有方法多针对病虫害预防、侧重于化学药剂封闭。为满足马铃薯抗性诱导、绿色投入品增加和农业绿色发展的需求,以马铃薯早熟品种‘希森3号’为材料,选用了通过工程菌发酵工艺制得的VDAL和Harpin免疫诱导蛋白干粉拌种,分别以不同浓度进行种薯处理,与常规化学药剂拌种方法进行比较,用调查统计的方法,获得不同处理对种薯萌发、出苗、植株生长、块茎发育和产量性状等方面的试验数据,综合评价其对马铃薯生长发育的影响。其中,Harpin 0.5ppm和VDAL 3ppm表现较好,与CK相比,早期出苗率提高20%以上,株高分别增高13.73%和9.30%,块茎膨大期的单株块茎重量增加20%以上,产量分别提高20.04%和12.99%。本研究确定了利用VDAL和Harpin进行种薯处理的有益效果,为马铃薯拌种新方法和新产品的研发提供了参考。     

Growth and Distribution of Dry Matter in a Drought Tolerant and a Susceptible Potato Cultivar under Normal and Water Deficit Condition

The growth behaviour of Dekama (drought tolerant) and Kufri Jyoti (drought susceptible) was studied using potted plants maintained at well watered condition and water deficit condition respectively. Periodic harvestings were done starting from 50 days after planting till maturity. Recordings of plant height, leaf area, dry weights of different plant parts, the proportion of thinner and thicker roots, stomatal conductance and water saturation deficit were obtained. The plant height, leaf area and dry weight of shoot decreased to nearly the same extent in both the cultivars under stress. The stomatal conductance decreased by 61.7 % in Dekama and by 64 % in Kufri Jyoti due to water stress. Water saturation deficit increased by about 80 % in both the cultivars. The ratios of root to shoot and that of thinner to thicker root increased due to stress in both cultivars and this increase was 85 % and 71 % in Dekama and 64 % and 19 % in Kufri Jyoti respectively. The distribution of dry matter to leaf, stem, root were more at the expense of tuber under stress conditions in both cultivars. However, the tolerant cultivar Dekama got adjusted to the stress condition, with more dry matter partitioned to tubers in the last two samplings. The study points out the factors responsible for better drought tolerance of Dekama compared to Kufri Jyoti and the possible physiological traits useful for selecting drought tolerant cultivars.     

Bio-mass Production in Potato in Relation to Evapotranspiration and Energy Summation Indices in Northern Hills of India

In field experiments conducted for 2 consecutive years at Shimla (31°06'N, 77°10'E at 2202 m above mean sea level with potato ( Solarium tuberosum L.), weekly means of rainfall (P), potential evapotranspiration (PET), pan evaporation (PAN) and photosynthetically active radiation (PAR) were estimated during the crop season. It was evident that from April to end of June, the evaporative demand was more than the precipitation and that the crop suffered from water deficit from emergence to tuber initiation. Four different energy summation indices accumulated over important phenological stages of growth and energy-use efficiency in terms of biomass production at these stages were estimated for two seasons. Weekly cumulative biomass production showed a significant correlation with accumulated PET, PAN and PAR in the four genotypes tested in year 2.     

Components of Visual Selection in Early Clonal Generations of a Potato Breeding Programme

In the first two clonal generations of a potato breeding programme, clones are visually selected for ‘plant appearance’. Selection for plant appearance based on unreplicated small plots is unreliable, due to significant genotype × environment interaction and high error variance. In order to improve the selection efficiency, component traits of plant appearance were identified and the effect of selection for these components was studied. Tuber yield was found to be the principal component of plant appearance while stolon length and tuber appearance contributed significantly, but to a lesser extent. Tuber yield had a higher heritability than plant appearance. Characters determining the appearance of stolons and tubers were found to have equal or lower heritabilities than plant appearance at 80 days after planting and somewhat higher heritabilities than plant appearance at 145 days after planting. Hence, since the expected and observed selection responses of the component characters have been found to be equivalent to that of plant appearance, selection for plant appearance cannot be improved upon by separately selecting for characters like tuber yield and tuber appearance.     

Effects of Dicyandiamide on Potato Performance

A nitrification inhibitor which blocks the conversion of ammonium to nitrate may reduce the risk of leaching of nitrate during the growing season. In field experiments in 1988—1990 a nitrogen fertilizer enriched with the nitrification inhibitor dicyandiamid (Alzon) was compared with a standard calcium-ammonium-nitrate fertilizer (CAN), using rates of N supply up to 360 kg ha⁻¹. There were no significant differences between CAN and Alzon with respect to: stem length, apical lateral branchmg, fresh and dry weights of haulms and tubers at maturity, and nitrogen uptake. Alzon-treated plants showed lower concentrations of nitrate in stems and leaves than CAN-treated plants.     

Planting Time and Seed Density Effects on Potato in Subtropical China

Planting times of potato in subtropical China vary and are often not optimal; their effects were studied in association with those of plant density. The research programme included 10 trials at three elevations (500, 750, 1200 m asl) in the spring and autumn seasons of 2 years with several contrasting varieties and different seed origins. Earlier planting in spring increased yield at 500 m asl. This effect was associated with better light use efficiency, higher rates of photosynthesis and more tubers per plant. At 750 m asl the effects of planting time in spring were the opposite: later planting increased yield. At 1200 m asl effects on yield were absent. Effects of planting time in autumn on yield were generally absent at all elevations, although plant stands at early planting were consistently and often severely reduced. Denser planting produced yields that were higher per unit area because of larger accumulated canopy cover but were lower per plant. Higher density consistently reduced plant stand. Density did not interact with planting time, not even in those experiments in which planting time also affected plant stands.
Optimal planting time depended on the amount of rainfall prior to planting especially in the autumn season, but also on cultivar and dormancy of the seed tubers used. The earlier variety yielded more than the later variety at low elevation, whereas the later variety yielded more at higher elevation. It is necessary to use cultivars that tuberize early to make better use of the limited growing period at lower elevation. The large variation of dormancy that affects plant growth and yield is caused primarily by differences in accumulated temperature sum (as affected by planting time, elevation of growth and storage, and season), genetics (variety), and their interaction with cultivation techniques.     

温度与棉株生理年龄的协同效应对棉纤维发育的影响

通过设置播期试验,使位于棉株不同果枝果节部位棉铃的纤维加厚发育期（铃龄25~50 d）处于不同温度条件下,研究温度与棉株生理年龄对棉纤维加厚发育及纤维比强度的影响,结果表明,温度与棉株生理年龄的影响存在互作效应,铃龄25~50 d日均温26℃左右时,棉株中部（7~9果枝）铃纤维蔗糖合成酶活性最高,β-1,3-葡聚糖酶活性最     

黑色地膜对甘薯生理特性及产量的影响

为探讨更为有效的甘薯覆膜栽培模式。采用田间试验与人工观测相结合的方法,研究不同覆膜栽培模式的生理特性和对产量的影响。结果表明：黑色地膜模式垄内10cm土壤温度平均比透明膜低2℃,比不覆盖地膜高1℃;薯块产量比透明膜高18.0%,比不覆盖地膜高20.4%。黑色地膜模式具有地温适宜、茎叶生长协调、叶面积系数合理、地上下部养分分配合理、净同化率较高的优点,这是最终薯块产量较高的原因。且不用喷洒除草剂,无污染,省工省劲。覆盖黑色地膜将成为栽培甘薯的新模式。     

Potential and Actual Yields of Potato at Different Elevations and in Different Seasons in Subtropical Southwest China

Potential potato yields of nine spring and five autumn seasons at elevations ranging from 150 to 2650 m asl in subtropical China were assessed by a simple growth model and compared with attainable and experimental (actual) yields. Generally, both potential and actual yields were higher at higher elevation because of cooler temperatures and longer growing periods. The spring crops showed higher potential and actual yields but had lower light use efficiencies than the autumn crops, especially at higher altitudes. Specific relationships were given for relevant potential and attainable yields over altitudes and seasons. Light use efficiency declined with ascending elevation during the autumn season. The ratio actual: potential yields (range0.25–0.56) and the ratio actual: potential light use efficiency (range 0.34–0.70) were low because of drought stress, hot temperatures in the low elevations, presence of diseases and pests, low quality seed, and lack of adequate fertilization.     

StGATA12对马铃薯(Solanum tuberosum)生长发育的影响

GATA转录因子是广泛存在于真核植物中的一类转录因子,它是锌指蛋白家族的成员,具有锌指结构,可以识别和特异性结合DNA序列。在调控植物开花时间、叶片延伸、花的发育以及光周期和光信号转导、叶绿素合成和碳、氮代谢调节等生物学过程中发挥重要作用。研究GATA家族的基因可以为作物增产提供一定的理论基础。本研究对转StGATA12基因的株系进行了生理生化分析,结果表明:转基因株系表现出叶面积、茎直径及单株结薯量增加的性状;叶绿素含量、淀粉含量增加;激素含量发生变化。由此可知,StGATA12转录因子在马铃薯叶绿素合成及激素平衡方面起着重要的调控作用。本研究初步阐明了StGATA12转录因子在马铃薯发育过程中的生物学功能和作用机制,丰富了植物GATA12基因的功能研究,并为培育优良的马铃薯新品种提供理论参考。     

Effects of Root-Zone Temperature on Growth and Development of Roots of Two Potato (Solanum tuberosum L.) Clones as Influenced by Plant Age, Nutrient Supply, and Light Intensity

The effects of supraoptimal root-zone temperature (30 °C) on growth and development of roots were investigated in water and soil culture with cuttings of two potato clones DTO-2 (heat tolerant) and LT-1 (heat sensitive) at different plant ages, with different compositions of the nutrient solution, and different light intensities. It is suggested that the negative relation between cutting age and heat susceptibility observed in our experiments, is a reflection of the decreasing shoot/root dry weight ratio rather than of age. Heat damage of root systems increased with the concentration of the nutrient solution, nitrate being the main factor responsible. The influence of light intensity on temperature mediated restriction of root growth was relatively small. However the roots of plants grown under low light intensity (60 W m⁻² PAR) appeared to be less stressed by supraoptimal temperature, i.e. roots appeared brighter, thinner and more ramified than plants growing at high light intensity (190 W m⁻²).     

Further Characterization of rollC Transgenic Tetraploid Potato Clones, and Influence of Daylength and Level of rolC Expression on Yield Parameters

Tetraploid rolC transformants have been analyzed considering the level of rolC expression and yield parameters. In rolC transformants a maximum of five integrated copies of the gene were detected by Southern analysis. A relation between copy number of the rolC gene, phenotypic rolC expression and intensity of morphological alterations was established. Three experiments were performed to assess the differential effect of the rolC gene on yield and its interaction with growth factors. In the first experiment, the influence of day length on plant morphological and physiological characters was studied. The phenotype of the transgenic plants with a low rolC expression was like the control under the two day-regimes tested, while the intermediate expressing genotype showed a different reaction. In the second and third experiment, tuber yield, tuber number and weight per tuber were recorded under short and long day conditions. When grown in smaller pots of 1.15 1 volume, the control plants had the highest yield of tubers under both day lengths tested. Yield decreased with increasing rolC expression. Tuber number revealed to be genotype dependent: it was higher for low rolC expressing plants and lower for intermediate rolC transformants (Experiment 2). In the third experiment the influence of variable pot size and shape was analyzed for one clone with intermediate and two with low level of rolC expression. Remarkable differences between pots and flat boxes of the same volume were noted for tuber yield and number: Under the two conditions the control clone and the low rolC expressing genotypes gave similar tuber yield and number in both growth containers, whereas the rolC intermediate genotype yielded significantly more in flat boxes. The effect of variable hormonal levels induced in transgenic plants through prokaryotic genes are discussed with the existence of non-predictable genotype in relation to environmental interactions. It is concluded that at least the agronomic performance of potatoes transformed with these genes cannot be predicted on the basis of simple linear relationships among the expression of the gene and of the traits.     

马铃薯SoFtsH基因全长cDNA克隆与在干旱条件下表达研究

FtsH (Filamentation Temperature-Sensitive H)是一种ATP和Zn²⁺依赖型金属蛋白酶，广泛存在于原核生物和真核生物中，在真核生物中是多基因家族。FtsH具有ATP酶活性、蛋白水解活性和分子伴侣活性，参与多种胁迫反应。从抗旱马铃薯（Solanum tuberosum）二倍体品系H145中分离得到cDNA-AFLP差异片段,利用RACE技术克隆了SoFtsH cDNA全长序列, 并对其进行分析。结果表明, 该序列包含完整的开放阅读框，长为723 bp, 编码129个氨基酸。SoFtsH具有2个铁氧化还原蛋白结合位点，并存在信号肽序列、跨膜区域和Zn²⁺结合域。SoFtsH基因序列与GenBank数据库中的其他FtsH基因进行同源序列比对, 并构建系统进化树, 发现该基因与番茄、烟草、拟南芥等高等植物FtsH基因同源性达90%以上。半定量RT-PCR和Northern Blot杂交结果表明SoFtsH基因在干旱胁迫下叶片和根系里的表达量明显增加, 且在抗旱品系H145与干旱敏感品系H214中表达模式不同。说明SoFtsH基因在马铃薯抗旱中起作用。     

马铃薯StSOD1基因酵母双杂交诱饵载体的构建及鉴定

为了筛选与马铃薯超氧化物歧化酶(superoxide dismutase,SOD)基因StSOD1作用的上游蛋白,构建其酵母双杂交诱饵重组载体。本研究利用PCR方法扩增得到马铃薯StSOD1的基因片段,通过与pMD-T18连接构建克隆载体,经验证构建成功后,与诱饵载体pGBKT7连接构建诱饵重组载体,经双酶切以及测序检测验证重组载体构建成功后,通过PEG/Li Ac法将诱饵载体pGBKT7-StSOD1与空载体pGBKT7分别转化到酵母AH109感受态细胞中,检测其是否有自激活作用和对酵母菌株的毒性作用。结果表明:经PCR扩增后得到了StSOD1基因,成功构建了诱饵重组载体pGBKT7-St SOD1,并且此诱饵载体无自激活活性和对酵母菌株的毒性作用。此研究结果可进一步为筛选与StSOD1互作的蛋白质及功能研究提供科学依据。     

纯合四倍体马铃薯遗传转化体系优化及转基因块茎的褐化鉴定

以农杆菌介导的反义POT32基因对纯合四倍体马铃薯不同外植体类型进行遗传转化,发现叶片预培养2d,侵染10min,共培养3d所得的抗性愈伤组织频率最高,污染频率最低。茎段预培养2～3d,侵染8min,共培养2d能够获得较高的抗性愈伤组织频率和较低的茎外植体污染率。试管微型薯在农杆菌工程菌侵染10min时获得高达52.8%的抗性愈伤组织频率。另外,1mg/LNAA 5mg/LGA3 2mg/LZT的激素配比能够有效促进不定芽分化并提高转化频率,其不定芽及转化频率分别为12.5%和8.3%。对块茎褐化的检测结果表明,转基因块茎的褐变强度和PPO活性明显低于对照(未转基因品种),且PPO活性与褐变强度及褐变指数呈正相关(r1=0.8244**,r3=0.7524*)。损伤后的转基因块茎的褐化出现时间及褐化指数明显迟于及低于对照。     

转基因纯合四倍体马铃薯多酚氧化酶活性及同工酶谱的变异

选择14个已插入反义PPO基因的纯合四倍体马铃薯“GD-9-qc”系列,进行叶片、微型薯PPO活性检测和同工酶分析,结果表明,不同品系间的叶片、微型薯PPO活性存在极显著差异,其中2个品系的叶片及8个品系的微型薯PPO活性明显低于对照;供试转基因品系间的叶片PPO同工酶谱带的颜色深浅表现差异,所示结果与PPO活性检测基本一致;     

水肥互作效应对陕北温室马铃薯生长及品质的影响

为在陕北地区栽培马铃薯(Solanum tuberosum)过程中选择合理的灌水施肥量,本研究采用随机区块组合的温室试验,滴灌施肥由3个灌水水平(100%ET0, 80%ET0和60%ET0)和3个施肥水平(100%F(N-P2O5-K2O=240-120-300 kg/hm2), 75%F和50%F)完全随机组成为9个处理(T1, 100%ET0×100%F;T2,80%ET0×75%F;T3, 60%ET0×50%F;T4, 100%ET0×75%F;T5, 80%ET0×50%F;T6, 60%ET0×100%F;T7, 100%ET0×50%F;T8, 80%ET0×100%F;T9, 60%ET0×70%F),以常规施肥(施肥量为50%F)和沟灌(灌水量为60%ET0)为对照处理(CK),研究水肥互作对马铃薯不同生育时期的株高、茎粗、叶面积、叶绿素含量、产量和品质的影响。结果显示,T9处理(60%ET0×70%F)条件下的马铃薯株高、茎粗生长优势较为明显,不会产生"徒长"现象,叶绿素含量较高,有利于马铃薯植株的生长,增产量明显且变异系数小,各品质指标含量较高且变异系数较小。因此,该处理可作为陕北地区温室马铃薯种植灌水施肥优选方案。本研究结果可为该地区优质马铃薯生产提供有力的技术支持。