Solanum L. section Solanum—a name change in S. villosum Miller

The discovery of an earlier epithet for the eglandular-haired subspecies of the Eurasian tetraploid Solarium villosum Miller has necessitated a name change and a new combination. The taxon previously called S. villosum Miller subsp. puniceum (Kirschl.) Edmonds now becomes S. villosum subsp. miniatum (Bernh. ex Willd.) Edmonds. Additional synonyms of this subspecies are given, together with the reasons for the selection of the epithet 'miniatum' rather than 'humile' which was published at the same time.     

The black nightshades (Solatium section Solatium) of the Indian subcontinent

Material of Solanum section Solanum from India and Pakistan is assignable to three species: a diploid, S. americanum; a tetraploid, S. villosum; and a hexaploid, S. nigrum. These species are distinguished by slight but consistent differences and a key is included to facilitate their identification. None of the members of section Solanum appears to be a weed of significant agronomic importance in this area, except in a few localized areas.     

Asymmetry of larval diet breadth and oviposition preference in Leptinotarsa undecimlineata

The relationship between preference and performance was studied under laboratory conditions for larvae and adult females of Leptinotarsa undecimlineata (Stål) (Coleoptera: Chrysomelidae). Leptinotarsa undecimlineata feeds exclusively on Solanum lanceolatum L. (Solanaceae) in the centre of Veracruz, Mexico. A common sympatric species, Solanum myriacanthum Dunal, is not used as host. We conducted a series of laboratory experiments to detect reasons for the exclusive use of one host plant. Leptinotarsa undecimlineata larvae were reared under laboratory conditions on both plant species, Solanum lanceolatum and S. myriacanthum . Length of larval stages, pupal weight, and percent adult eclosion were compared, and larval preference for both Solanum species was tested. Upon eclosion, adult females were exposed to each of the plants, and the effect of larval diet on adult preference was determined. Oviposition on both Solanum species was observed in no-choice tests. Larvae showed no significant preferences for either plant species. Pupal weight, however, was significantly higher on S. lanceolatum . Female beetles significantly preferred S. lanceolatum leaves, and no effect of preimaginal conditioning was found. Females reproduced in lower numbers after feeding on S. myriacanthum , oviposition initiated later, and females laid fewer eggs than females fed with S. lanceolatum . No female accepted S. myriacanthum for oviposition. Results obtained suggest that the potential host breadth of L. undecimlineata is broader in larvae than in female beetles.     

Taxonomic studies on Solarium section Solarium (Maurella)

Various taxonomic methods are being used to clarify the systematics of Solarium section Solanum , the large and variable species group centring around the black nightshade, S. nigrum. To put the experimental work into perspective, a summary of former taxonomic treatments is given, together with an outline of the provisional taxonomic framework of the section, initially established from earlier classical studies, and supplemented by later experimental work.
Experimentation with living populations has shown that Solanum taxonomy is complicated by several factors. In addition to the historical factors, phenotypic plasticity, genetic variation, the existence of a polyploid series, and the possibilities of interspecific hybridization accompanied by various pre- and post-zygotic isolating mechanisms are dealt with.
The various taxonomic categories attached to Solanum accessions during earlier classical studies derive support from the crossability behaviour of the taxa concerned. Morphological divergence is generally accompanied by genetical isolation which can manifest itself at any time between pollination and the maturation of the F₂ progeny. Data from the hybridization studies, in which 14 diploid species, five tetraploid species, four hexaploid species and one octoploid taxon were used, are presented in detail.     

内蒙古被子植物新资料

报道了内蒙古3个新分布记录属:鼠尾草属(Salvia L.)、单蕊草属(Cinna L.)、裂稃茅属(Schizachne Hackel);3个新分布记录种:荫生鼠尾草(Salvia umbratica Hance)、红果龙葵(Solanum villosum Miller)、单蕊草[Cinna latifolia (Trev.) Griseb.];1个新记录亚种: 裂稃茅[Schizachne purpurascens (Torrey) Swallen subsp.callosa (Turcz.) T.Koyama & Kawano];1个黄芪属(豆科)新变型--皇甫川黄芪.     

Ectopic AtCBF1 over-expression enhances freezing tolerance and induces cold acclimation-associated physiological modifications in potato

We studied the effect of ectopic AtCBF over-expression on physiological alterations that occur during cold exposure in frost-sensitive Solanum tuberosum and frost-tolerant Solanum commersonii . Relative to wild-type plants, ectopic AtCBF1 over-expression induced expression of COR genes without a cold stimulus in both species, and imparted a significant freezing tolerance gain in both species: 2 °C in S. tuberosum and up to 4 °C in S. commersonii . Transgenic S. commersonii displayed improved cold acclimation potential, whereas transgenic S. tuberosum was still incapable of cold acclimation. During cold treatment, leaves of wild-type S. commersonii showed significant thickening resulting from palisade cell lengthening and intercellular space enlargement, whereas those of S. tuberosum did not. Ectopic AtCBF1 activity induced these same leaf alterations in the absence of cold in both species. In transgenic S. commersonii , AtCBF1 activity also mimicked cold treatment by increasing proline and total sugar contents in the absence of cold. Relative to wild type, transgenic S. commersonii leaves were darker green, had higher chlorophyll and lower anthocyanin levels, greater stomatal numbers, and displayed greater photosynthetic capacity, suggesting higher productivity potential. These results suggest an endogenous CBF pathway is involved in many of the structural, biochemical and physiological alterations associated with cold acclimation in these Solanum species.     

Host plant defenses of black (Solanum nigrum L.) and red nightshade (Solanum villosum Mill.) against specialist Solanaceae herbivore Leptinotarsa decemlineata (Say)

Black nightshade (Solanum nigrum, S. nigrum L.) and red nightshade ( Solanum villosum, S. villosum Mill.) are medicinal plants from the Solanaceae family that synthesize glycoalkaloids and other secondary metabolites. To recognize the potential insecticide activity of these compounds, leaf extracts (containing glycoalkaloid and methanol fractions) were tested for enzyme inhibition, antifeedant activity and toxicity. For in‐vitro glutathione S‐transferase (GST) inhibition activity, we used insecticide‐resistant Colorado potato beetle, Leptinotarsa decemlineata ( L. decemlineata; Say) midgut and fat‐body homogenate. In‐vivo toxicity and the antifeedant activity were performed using larval bioassays. The methanol extracts had greater GST inhibitory activity compared to the glycoalkaloids, as well as greater 2nd instar larvae mortality and antifeedant activity. Furthermore, the green leaf volatile compound, cis‐hex‐3‐enyl acetate, at the concentration of 5 ppm, caused 50% mortality of 2nd instar larvae. Our findings suggest the potential usefulness of S. nigrum and S. villosum extracts to control L. decemlineata.     

Leaf cuticular n-alkanes as markers in the chemotaxonomy of the eggplant (Solanum melongena L.) and related species

The complex of species formed by eggplant (Solanum melongena L.) and its wild and weedy relatives (mainly S. incanum L. and S. insanum L.) is characterised by an extreme morphological divergence that is not always associated with genetic variation. The taxonomy of so‐called ‘spiny Solanum’ species (subgenus Leptostemonum) is therefore extremely unclear. Cultivated eggplant lacks resistance to pests that frequently occur among the wild forms and species. As these wild plants are a potential gene pool for improvement of eggplant cultivars, knowledge of the characteristics of taxonomic relations between plants of different origin is crucial. We suggest using the leaf cuticular n‐alkane chain length distribution pattern as an alternative taxonomic marker for eggplant and related species. The results are in good agreement with current knowledge of the systematics of these plants; at the same time, the method developed here is useful for verifying plant identification based on morphological traits. Analysis of 13 eggplant cultivars, five accessions of S. incanum and two lines of S. macrocarpon enabled the intraspecific variation within eggplant to be assessed as low. There was wide variability among S. incanum accessions, probably because plants described as S. incanum are members of a number of different species. Some Asian accessions (sometimes described as S. insanum) were found to be almost identical to S. melongena, while a truly wild African S. incanum plant showed extensive similarity. The usefulness of the chemotaxonomic approach in dealing with the S. melongena–S. incanum complex is discussed.     

The fruit cuticles of wild tomato species exhibit architectural and chemical diversity, providing a new model for studying the evolution of cuticle function

The cuticle covers the aerial epidermis of land plants and plays a primary role in water regulation and protection from external stresses. Remarkable species diversity in the structure and composition of its components, cutin and wax, have been catalogued, but few functional or genetic correlations have emerged. Tomato (Solanum lycopersicum) is part of a complex of closely related wild species endemic to the northern Andes and the Galapagos Islands (Solanum Sect. Lycopersicon). Although sharing an ancestor <7 million years ago, these species are found in diverse environments and are subject to unique selective pressures. Furthermore, they are genetically tractable, since they can be crossed with S. lycopersicum, which has a sequenced genome. With the aim of evaluating the relationships between evolution, structure and function of the cuticle, we characterized the morphological and chemical diversity of fruit cuticles of seven species from Solanum Sect. Lycopersicon. Striking differences in cuticular architecture and quantities of cutin and waxes were observed, with the wax coverage of wild species exceeding that of S. lycopersicum by up to seven fold. Wax composition varied in the occurrence of wax esters and triterpenoid isomers. Using a Solanum habrochaites introgression line population, we mapped triterpenoid differences to a genomic region that includes two S. lycopersicum triterpene synthases. Based on known metabolic pathways for acyl wax compounds, hypotheses are discussed to explain the appearance of wax esters with atypical chain lengths. These results establish a model system for understanding the ecological and evolutionary functional genomics of plant cuticles.     

Screening of non-tuber bearing Solanaceae for resistance to and induction of juvenile hatch of potato cyst nematodes and their potential for trap cropping

Ninety accessions of non‐tuber bearing Solanaceae were screened for (i) resistance to and (ii) stimulatory effect on juvenile hatch of potato cyst nematodes, and (iii) their growth under temperate climatic conditions. All plant species belonging to the genus Solanum tested induced hatching but this effect was most pronounced for plant species of the Solanum nigrum complex. Hatching of juveniles was hardly or not stimulated by other plant genera of the Solanaceae. Solanum sisymbriifolium combined a high hatching effect with complete resistance to both Globodera rosiochiensis and G pallida. Two S. nigrum varieties showed full resistance to G rostochiensis and a high level of resistance to G pallida. Moreover, S. sisymbriifolium and the two varieties of S. nigrum performed very well under Dutch field conditions and, therefore, they are suggested as candidate trap crops for the control of potato cyst nematodes.     

HT proteins contribute to S‐RNase‐independent pollen rejection in Solanum

Plants have mechanisms to recognize and reject pollen from other species. Although widespread, these mechanisms are less well understood than the self‐incompatibility (SI) mechanisms plants use to reject pollen from close relatives. Previous studies have shown that some interspecific reproductive barriers (IRBs) are related to SI in the Solanaceae. For example, the pistil SI proteins S‐RNase and HT protein function in a pistil‐side IRB that causes rejection of pollen from self‐compatible (SC) red/orange‐fruited species in the tomato clade. However, S‐RNase‐independent IRBs also clearly contribute to rejecting pollen from these species. We investigated S‐RNase‐independent rejection of Solanum lycopersicum pollen by SC Solanum pennellii LA0716, SC. Solanum habrochaites LA0407, and SC Solanum arcanum LA2157, which lack functional S‐RNase expression. We found that all three accessions express HT proteins, which previously had been known to function only in conjunction with S‐RNase, and then used RNAi to test whether they also function in S‐RNase‐independent pollen rejection. Suppressing HT expression in SC S. pennellii LA0716 allows S. lycopersicum pollen tubes to penetrate farther into the pistil in HT suppressed plants, but not to reach the ovary. In contrast, suppressing HT expression in SC. Solanum habrochaites LA0407 and in SC S. arcanum LA2157 allows S. lycopersicum pollen tubes to penetrate to the ovary and produce hybrids that, otherwise, would be difficult to obtain. Thus, HT proteins are implicated in both S‐RNase‐dependent and S‐RNase‐independent pollen rejection. The results support the view that overall compatibility results from multiple pollen–pistil interactions with additive effects.     

Taxonomical notes on selected freshwater fish species described from northern and central Vietnam(Cypriniformes:Balitoridae,Cobitidae,Cyprinidae,Nemacheilidae; Perciformes:Channidae,Osphronemidae;Synbranchiformes:Mastacembelidae)

Selected,little known taxa of northern and central Vietnamese freshwater fish species are reviewed.Nomenclatural acts are taken:Hemibarbus lehoai is placed in synonymy of H.maculatus,Paracobitis hagiangensis in synonymy of Schistura caudofurca.A neotype of Micronemacheilus bacmeensis is assigned.The name Channa hanamensis is treated as a nomen nudum.Two labeonine species described from China are nomenclaturally affected:Garra findolabium is transferred to Vinagarra and its specific epithet is treated as a noun in apposition;the specific epithet of Sinigarra napoense is corrected to napoensis.     

A revision of the Solatium sessile species group (section Geminata pro parte: Solanaceae)

KNAPP, S., 1991. A revision of the Solatium sessile species (sectio Geminata pro parte : Solanaceae ). The taxonomy of the Solanum sessile species group (a part of the large and unwieldy section Geminata) is reviewed, based on detailed field and herbarium studies. Members of the group are found from Mexico to Bolivia in a variety of habitats. Ten species are recognized: S. obovalifolium, S. sessile, S. monadelphum, S. turgidum, S. triste, S. chlamydogynum, S. rovirosanum, S. palmillae, S. oppositifolium and conferliseriatum.     

Variations in resistance against Phthorimaea operculella in wild potato tubers

Tuber resistance can contribute to current management strategies against the potato tuber moth, Phthorimaea operculella Zeller (Lepidoptera: Gelechiidae), in field and stored potatoes. Wild potatoes represent a potential source of novel resistance traits against the moth. We assessed resistance in three wild potato species, Solanum multiinterruptum Bitt., Solanum sparsipilum (Bitt.) Juz. & Buk., and Solanum wittmackii Bitt. against neonate and developing tuber moth larvae. All three species had high levels of resistance but accessions of S. sparsipilum and S. wittmackii were significantly more resistant. Resistance in S. multiinterruptum was generally concentrated in the tuber periderm, whereas in S. sparsipilum and S. wittmackii resistance was mainly cortex‐based. Unidentified cortex‐resistance factors in all three species reduced survival and increased larval and pupal development times, but had no apparent effects on the pupal weights of survivors. A high proportion of larvae abandoned or died within tubers of S. wittmackii, which has particularly high levels of unidentified cortex‐based defenses. Resistance decreased in S. multiinterruptum and S. sparsipilum as tubers sprouted but was more stable in S. wittmackii. Periderm‐based resistance was more stable than cortex‐based resistance in S. multiinterruptum during sprouting. In contrast, cortex‐based resistance was stable in tubers of S. wittmackii as these sprouted, and resistance may have increased on some older sprouting tubers. Solanum multiinterruptum and S. sparsipilum are proposed as potential sources of resistance against the potato tuber moth.     

Resistance of three wild tuber-bearing potatoes to the Colorado potato beetle

The resistance of Solanum okadae Hawkes & Hjert. (PI 458367), Solanum oplocense Hawkes (PI 473368), and Solanum tarijense Hawkes (PI 414150) to the Colorado potato beetle, Leptinotarsa decemlineata (Say) (Chrysomelidae: Chrysomelini), was studied. In replicated field trials all three accessions showed a high level of resistance to the beetle. No significant genetic variability between genotypes of the same species was found. Results from host acceptance behavior experiments, suitability for larval development tests, foliage consumption tests, and adult survival and oviposition tests supported the hypothesis that the mode of resistance differs between the three wild Solanum species. Solanum okadae and S. oplocense affected host acceptance and consumption. Because the beetle reacted differently to these two species it was hypothesized that the antifeedant chemical(s) differed in nature or quantity. S. tarijense contrasted with the other two species by affecting mostly adult colonization and oviposition.     

Metabolomics-assisted refinement of the pathways of steroidal glycoalkaloid biosynthesis in the tomato clade

Steroidal glycoalkaloids (SGAs) are nitrogen-con-taining secondary metabolites of the Solanum species, which are known to have large chemical and bioactive diversity in nature. While recent effort and ...