Tuber-bearing Solanum Research Articles

Chloroplast DNA variation between the common cultivated potato (Solanum tuberosum ssp. tuberosum) and several South American relatives

Chloroplast DNA (ctDNA) from the tuberbearing Solanum species tuberosum, vernei, phureja, and chacoense has been compared by restriction endonuclease analysis. Digestion by Hind III or Xba I reveal no differences, but digestion with Bam HI and Eco RI reveals minor differences in the ctDNA among these species. The ctDNA restriction patterns of the tetraploid common cultivated potato of North America and Europe, S. tuberosum ssp. tuberosum and the South American tetraploid, S. tuberosum ssp. andigena are identical for all four restriction endonucleases. These data suggest that ssp. tuberosum and ssp. andigena contain similar ctDNA and therefore may share a common ancestor, or direct lineage. The ctDNA restriction patterns of S. vernei and S. chacoense are identical for all four restriction endonucleases, and S. phureja ctDNA, can be distinguished from the other diploid ctDNAs by digestion with Bam HI. None of the diploids analyzed contain ctDNA identical to the tetraploids and therefore either did not contribute their chloroplast genomes to the evolution of the tetraploids, or the ctDNA has diverged since this evolutionary event. The ctDNAs studied did not contain restriction polymorphisms which could be correlated to cytoplasmic male sterility in Solanum. This is the first demonstration of ctDNA diversity in the tuber-bearing Solanum species.

The pattern of megasporogenesis and megagametogenesis in diploid Solanum species hybrids; its relevance to the origin of 2n-eggs and the induction of apomixis

Megasporogenesis and megagametogenesis in diploid tuber-bearing Solanum species hybrids were studied and illustrated in detail. Megagametogenesis followed the normal or Polygonum type of embryo sac development. In megasporogenesis a few regularly occurring deviations from what is usually considered to be the normal course of megasporogenesis were detected. Firstly, the development of a surplus of adjacent or non-adjacent megaspore mother cells in a single ovule was frequently observed. As they eventually may give rise to normally reduced, sexual embryo sacs, it is concluded that the archesporium in potato cannot be delimited to a single cell or even a group of adjacent cells in the ovule. Secondly, the micropylar daughter cell which is formed after completion of the first division was often found to degenerate before the onset or completion of the second division giving rise to a triad instead of a tetrad of megaspores. The spatial arrangement of megaspores within the ovule was found to vary according to the variation in the relative orientation of second division spindles. It is concluded that these deviations should be considered random legitimate variations of megasporogenesis rather than systematic abnormal events. The implications of the overall pattern of megasporogenesis for the formation of 2n-eggs and the attempts to induce diplosporic or aposporic apomixis in potato are discussed.

Natural triploid hybrids between Solanum acauleBitter and S. infundibuliformePhilippi in the province of Jujuy, Argentina

The occurrence of natural triploid hybrids between tetraploid Solanum acauleBitter subsp. acaule and diploid S. infundibuliformePhilippi both tuber-bearing Solanums, in the Puna region of Jujuy, is reported. The natural hybrids, which are morphologically intermediate between their putative parents and completely male sterile, have a somatic chromosome number of 36. The artificial hybrids, obtained by crossing both parental species, closely resemble the natural ones thereby confirming their parentage. It is proposed to designate the natural hybrids Solanum x viirsooi hybr. nov.

Mayer's hemalum-methyl salicylate: a stain-clearing technique for observations within whole ovules.

Nondissected ovaries of tuber-bearing Solanum sp. were stained with Mayer's hemalum, a positive stain for chromatin and nucleoli, and then optically cleared with methyl salicylate, a clearing agent. Clarity, resolution and contrast within the ovules dissected from ovaries were comparable to those of sectioned, paraffin embedded ovaries. Contrast within ovules greatly exceeded that of unstained and nonspecifically stained clearings, and eliminated the need of special optics, i.e., Nomarski interference-contrast optics, for optimal viewing and photography. Much less time and labor were required than for embedded specimens. Usefulness of the technique for cytogenetic and cytological research was verified by analyzing meiosis and other features of megasporogenesis and megagametogenesis in normal, and in two meiotic mutants, of Solanum. The results illustrate the usefulness of combined Mayer's hemalum staining and methyl salicylate clearing, and suggest additional stain-clearing agent combinations have potential for cytological and cytogenetic research. Preliminary results with other species suggest the technique may also be useful for classroom instruction.

An easy and reliable method for the rejuvenation of self-incompatible tuber-bearing Solanum species

True seed production was studied of self-incompatible diploid tuber-bearing Solanum species grown in the field under spatial isolation in cereals in 1979 and 1982. In comparison with hand pollinations in the greenhouse, extremely high amounts of seeds were obtained, the potential seed yield of 20 plants in 1979 being 66 000 to 540 000. As no indication of interspecific hybridization was found, the chosen isolation is considered to be adequate. It is concluded that sexual propagation of self-incompatible tuber-bearing Solanum species in the field is highly efficient.

New tuber-bearing Solanum taxa from Bolivia and northern Argentina

Six new Solarium taxa, from Bolivia and northern Argentina, belonging to Solarium section Petota, are described.

Frost Injury and Heterogeneous Ice Nucleation in Leaves of Tuber-Bearing Solanum Species

The heterogeneous ice nucleation characteristics and frost injury in supercooled leaves upon ice formation were studied in nonhardened and cold-hardened species and crosses of tuber-bearing Solanum. The ice nucleation activity of the leaves was low at temperatures just below 0 degrees C and further decreased as a result of cold acclimation. In the absence of supercooling, the nonhardened and cold-hardened leaves tolerated extracellular freezing between -3.5 degrees and -8.5 degrees C. However, if ice initiation in the supercooled leaves occurred at any temperature below -2.6 degrees C, the leaves were lethally injured.To prevent supercooling in these leaves, various nucleants were tested for their ice nucleating ability. One% aqueous suspensions of fluorophlogopite and acetoacetanilide were found to be effective in ice nucleation of the Solanum leaves above -1 degrees C. They had threshold temperatures of -0.7 degrees and -0.8 degrees C, respectively, for freezing in distilled H(2)O. Although freezing could be initiated in the Solanum leaves above -1 degrees C with both the nucleants, 1% aqueous fluorophlogopite suspension showed overall higher ice nucleation activity than acetoacetanilide and was nontoxic to the leaves. The cold-hardened leaves survived between -2.5 degrees and -6.5 degrees using 1% aqueous fluorophlogopite suspension as a nucleant. The killing temperatures in the cold-hardened leaves were similar to those determined using ice as a nucleant. However, in the nonhardened leaves, use of fluorophlogopite as a nucleant resulted in lethal injury at higher temperatures than those estimated using ice as a nucleant.

Resistance to potato cyst-nematodes in tuber-bearing Solanum species and its geographical distribution

Numerous accessions maintained in the potato collection of the ‘German-Netherlands Potato Department of the Gene Bank in the Federal Research Center for Agriculture Braunschweig-Volkenrode’ have been evaluated for resistance to potato cyst-nematodes. The results of several years testing for resistance to both Globodera rostochiensis and G. pallida are presented in this paper. It is concluded that resistance is predominantly found in some 17 species belonging to the series Tuberosa which have their geographical distribution mainly in the Andes. The geographical distribution of species with G. pallida resistance is discussed and it is pointed out that this resistance is mainly concentrated on the eastern slopes of the Andes (Cordillera oriental).

Interrelationships of Freezing and Heat Tolerance in Tuber-bearing Solanum species1

Abstract Several tuber-bearing Solanum species with different levels of frost hardiness and different capacities for cold acclimation were studied for the interrelationship of freezing and heat tolerance after cold and heat acclimation. Cold acclimation could increase the frost hardiness in some species as previously reported, but except for S. commersonii it did not change the heat hardiness in species studied. Heat acclimation, on the other hand, could increase the heat hardiness in all tested species without affecting their frost hardiness. There is no systematic relationship between freezing and heat tolerance and no correlation in heat hardiness between the controls and the heat acclimated plants. The results indicate that the mechanisms of cold and heat acclimation in the potato appear to be independent of each other.

Solanum sawyeri, a new wild potato species from the Peruvian tropics

During my ongoing study of the systematics of the Peruvian wild tuberbearing Solanums I have reviewed some rare and interesting collections made in the past which previously had seemed very difficult to classify correctly. After reviewing and comparing some of these specimens with other collections gathered in the main herbaria of U.S.A. and Europe, I am convinced of the existence of some still undescribed species such as the one I am presenting here under the name ofSolanum sawyeri in honor of Dr. Richard Leander Sawyer, promoter and founder of The International Potato Center located at Lima, Peru. Solanum sawyeri, is acclimated to the warm humid tropics of Southern Peru. It grows in forests of the low land regions of the Eastern province of Urubamba in the Department of Cusco and thereafter might serve as a source of breeding material for those who want to select potato cultivars for the low land tropics. This species belongs to the series Tuberosa with 2n = 2× = 24 chromosomes.

Glycoalkaloids of wild, tuber-bearing Solanum species

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTGlycoalkaloids of wild, tuber-bearing Solanum speciesPeter Gregory, Stephen L. Sinden, Stanley F. Osman, Ward M. Tingey, and Deborah A. ChessinCite this: J. Agric. Food Chem. 1981, 29, 6, 1212–1215Publication Date (Print):November 1, 1981Publication History Published online1 May 2002Published inissue 1 November 1981https://doi.org/10.1021/jf00108a028RIGHTS & PERMISSIONSArticle Views255Altmetric-Citations67LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (595 KB) Get e-Alerts Get e-Alerts

Relationship between Heat and Frost Resistance of Tuber-Bearing Solanum Species: Effect of Cold Acclimation on Heat Resistance

A possible relationship between heat and freezing-stress resistance was investigated in four potato species. These species differed in degree of freezing-stress resistance and ability to acclimate to cold. The 2, 3, 5-triphenyl tetrazolium chloride reduction and the conductivity test were used to evaluate the relative heat and freezing-stress resistance of excised leaflets. Data from both tests failed to show a systematic relationship between heat and freezing-stress resistance in the four potato species. The cultivated species, Solanum tuberosum, had the lowest level of freezing-stress resistance and one of the highest levels of heat-stress resistance. One noncultivated accession had a high degree of frost and heat resistance, whereas the other three accessions had a high degree of frost but poor heat resistance. Fifteen days at 5/2 C day/night did not increase heat- and freezing-stress resistance of S. tuberosum but increased both heat- and freezing-stress resistance in S. commersonii and other species capable of cold acclimation. These results show that (1) resistance to heat and freezing stress is not always mutually exclusive; (2) if a plant is capable of increasing freezing-stress resistance during cold acclimation, it also seems to have the ability to increase heat-stress resistance; and (3) the enzymes that participate in oxidation-reduction reactions and active transport of ions are sensitive to heat injury.

Liquid Nitrogen Preservation of Pollen from Tuber-bearing Solanum Species1,2

Abstract In short-term exposure studies pollen from several tuber-bearing Solanum species retained high viability after rapid cooling in liquid nitrogen, provided the initial moisture content was less than 35–40%. Some pollen samples dried over anhydrous CaCl2 to low moisture levels required rehydration before assessing germination in vitro.

Solanum etuberosum: A model for studying the cryobiology of shoot-tips in the tuber-bearing Solanum species

A high percentage of isolated shoot tips of Solanum etuberosum survived slow cooling at 0.3°C/min to −40°C. Below this temperature survival decreased. High survival could be obtained at −196°C by a two-step procedure of slow cooling to −40°C followed by immersion in liquid nitrogen. Dimethylsulfoxide was the cryoprotectant used in all studies. Essential for survival under these conditions was the culture in light of isolated shoot tips for a period of time (about 2 days) before addition of cryoprotectant and subsequent freezing. Under these conditions, formation of a multiple shoot mass was the predominant morphogenetic response.

Characteristics of Cold Acclimation and Deacclimation in Tuber-bearing Solanum Species

The effect of temperatures on cold acclimation and deacclimation in foliage tissues was studied in Solanum commersonii (Oka 4583), a tuber-bearing potato. The threshold temperature for cold acclimation was about 12 C. In a temperature range of 2 to 12 C, the increase in hardiness was dependent on the acclimating temperature; the lower the acclimating temperature, the more hardiness achieved. A day/night temperature of 2 C, regardless of photoperiod, appeared to the optimum acclimating temperature for the Solanum species studied. A subfreezing temperature hardened plants less effectively. The maximum level of hardiness could be reached after 15 days of cold acclimation. However, it took only 1 day to deacclimate the hardened plants to a preacclimation level when plants were subjected to a warm regime from cold. The degree of deacclimation was dependent on the temperature of the warm regime.Based on cold tolerance and the capacity to acclimate to cold, tuber-bearing Solanum species could be grouped into five categories. Chilling injury was also observed in some of the tuber-bearing Solanum species.

Die Flavonoid-Muster der knollentragenden Solanum-Arten I. Charakterisierung der Flavonoid-Glycoside

Leaf flavonoids were isolated from 107 species including a few natural hybrids and not yet described taxa of the section Tuberarium, subgenus Solanum, using column- and thinlayer-chromatography. 38 different flavonol glycosides and one flavone glycoside were fully or partly characterized by means of UV-spectroscopy and different hydrolysis methods. Among them are the following substances reported for the first time in tuber-bearing Solanums: Quercetin-3-arabinoside and -xyloside; 3-galactosides of quercetin, kaempferol and isorhamnetin; isorhamnetin-3-rutinoside; 3-neohesperidosides of quercetin and kaempferol; quercetin- and kaempferol-3-(2G-rhamnosyl-rutinoside) and kaempferol-3-sophorotrioside7-rhamnoside, acylated with p-coumaric- or ferulic acid. For all these substances Rf-values in different solvent systems and spectral data are given.

Successful hybridization of non-tuberous Solanum etuberosum Lind. and tuberbearing S. pinnatisectum Dun.

The results of extensive crosses between the non-tuberous species Solanum brevidens and S. etuberosum on the one hand and ten tuber-bearing Solanum species on the other are presented. Three crosses gave rise to viable progeny. Two progenies consisted of diploid plants only of the strictly self-incompatible species of the mother parent. One cross, viz. S. etuberosum × S. pinnatisectum, produced highly vigorous but fully male sterile F1 hybrids. It is suggested that this hybrid together with those between the tomato, Lycopersicon esculentum, and S, pennellii and S. lycopersicoides constitute piers of a bridge between tomato and potato species which in the future might enable gene transfer between these two crops via their wild relatives. However, such idea has to be treated with all proper reserve. The production of this new hybrid is the first step in making accessible to potato breeding the valuable genes which have been detected in S. brevidens and S. etuberosum, viz. the genes for high resistance to frost, leafroll and Y-virus.

Glycoalkaloid composition of wild and cultivated tuber-bearing Solanum species of potential value in potato breeding programs

Glycoalkaloid composition of wild and cultivated tuber-bearing Solanum species of potential value in potato breeding programs

2n gametes in potato species and their function in sexual polyploidization

The extent and pattern of polyploidy in the tuber-bearing Solanums varies among the many taxanomic series that have been identified in this subsection of Solanum. While several series appear to be entirely diploid, others exhibit a range of ploidy levels from 2x to 6x, and some contain only polyploid species.

Polyploid evolution via 2n gametes

Polyploid evolution is evident in several important taxonomic series of the tuber-bearing Solanums. Polyploids can result from the functioning of 2n gametes following both intra and inter-ploidy matings. The bilateral and unilateral sexual polyploidizations (BSP and USP, respectively) are greatly facilitated by the existence of genetically determined 2n gametes. Many species, in series containing polyploids, have individuals with 2n gametes. The genetic basis of 2n pollen formation has been established in Phurejahaploid Tuberosum hybrids, and the genetic basis of 2n egg formation is being investigated in these hybrids andS. chacoense. Preliminary results indicate that relatively few genes may be involved. FDR and to a lesser extent SDR 2n gametes avoid the inbreeding in the polyploid that is maximal with somatic doubling. The vigor, fertility and competitive ability of a founder polyploid are dependent on minimizing inbreeding depression. Even more important, polyploids, particularly from FDR 2n gametes, inherit the beneficial epistatic interactions of the parent(s). Genetically determined 2n gametes make systematic sexual polyploidization a recurring phenomenon in two ways. For example, initial BSP of two diploids gives rise to a tetraploid, and thereafter USP ensures continuing contact between ploidy levels resulting in unidirectional introgression. Triploids can also be involved in polyploid evolution if they produce 2n gametes by FDR. Artificial hybridizations indicate that 2n gametes, by overcoming crossing barriers between various ploidy levels, provide the opportunity for continuous gene flow.