Genetic Variability and Fruit Morphological Diversity in the Tomato Germplasm

Tomato (Solanum lycopersicum L.), broadly divided into two varieties: Solanum lycopersicum var. lycopersicum (domesticated tomato) and the weedy Solanum lycopersicum var. cerasiforme (cherry tomato), is closely related to the wild tomato species Solanum pimpinellifolium. Studies show presence of a very low genetic diversity among tomato cultivars, which is estimated to be lower than 5% of that available in nature. With the estimation of such a low level of genetic variability in the germplasm, assessment of the extent and nature of the genetic variation in tomatoes would be important for breeding and genetic resource conservation programs. I used AFLP data to analyze the genetic variability within the germplasm of Solanum lycopersicum var. cerasiforme (112 accessions), and genetic variability along with fruit morphological diversity in the accessions of Solanum lycopersicum var. lycopersicum (219 accessions) from different parts of the World. Cherry tomato (Solanum lycopersicum var. cerasiforme) in terms of genetic distance and molecular variance (1% molecular variance) was very close to Solanum lycopersicum var. lycopersicum than its wild sister taxa Solanum pimpinellifolium (20% molecular variance). It also showed more genetic diversity (Hj, 0.42052-0.48361) than that of S. l. lycopersicum (Hj, 0.26008-0.42017); and among its geographic groups, South American accessions had more genetic diversity (Hj, 0.43703-0.48361) than that of Mesoamerican (Hj, 0.42052-0.46946) and Caribbean accessions (Hj, 0.42287). The germplasm of S. l. lycopersicum showed presence of more genetic diversity in the accessions from Western South America, Caribbean and Mediterranean regions (Hj, 0.42017), and Mesoamerica (Hj, 0.41790), the places associated with tomato domestication and subsequent dispersal after domestication.Studied tomato germplasm was divided into three genetically distinct clusters (K=3), and one of the clusters (cluster 3) in S. l. lycopersicu

Preliminary Phytochemical Screening of Healthy and Leaf Curl Virus Infected Tomato (Solanum Lycopersicum) Leaves

The present investigation deals with the determination of phytochemical constituents of healthy and leaf curl virus infected tomato (Solanum lycopersicum) leaves. Specimens were collected from Koraye in Zaria and transported to the Herbarium unit for proper authentication. Healthy and curl leaves of Solanum lycopersicum were washed thoroughly three times with running tap water and once with sterile distilled water, air dried at temperature on a sterile blotter. After complete drying, young leaves were pulverized. The powdered material was weighed and kept in air tight container in dark place for further extraction procedure. Extraction was done by methanol method, where 100g each of pulverized powder of both healthy and infected Solanum lycopersicum leaves was put in a cornical flask and (1000ml) of measuring cylinder was used to measure 500ml of 70% methanol. The results obtained from the qualitative phytochemical analysis revealed the presence of; Alkaloids, Flavonoids, Tanins, Cardiac glycosides, Phenols and Saponins in both healthy and infected leaves of Solanum lycopersicum and the absence of; Carbohydrates, Steroids and Anthroquinone in both healthy and infected leaves of Solanum lycopersicum. While the quantitative analysis revealed the presence of 8.2% and 3.8% Alkaloids, 49.6% and 48.2% Flavonoids, 30.6% and 19.99%, Tanins 30.6% and 19.9%, Phenols 13.6% and 7.022% Saponins 1.2% and 0.1% in both healthy and infected leaf curl of Solanum lycopersicum. Evidently, from the above investigation there are no reducing sugars in Solanum lycopersicum leaves and there are metabolites in some healthy and infected leaf curl of Solanum lycopersicum leaves

Annotated world bibliography of host fruits of Bactrocera latifrons (Hendel) (Diptera: Tephritidae)

Bactrocera latifrons (Hendel) (Diptera: Tephritidae) infests fruits and vegetables of a number of different plant species, with host plants primarily found in the plant families Solanaceae and Cucurbitaceae. Although B. latifrons is of primarily Asian distribution (e.g., Pakistan, India, Sri Lanka, Burma, China [Fujian, Yunnan, Hong Kong, Hainan], Thailand, Laos, Vietnam, Malaysia, Singapore, Taiwan, and Brunei), its range has expanded through introductions into Hawaii, Okinawa, Tanzania, and Kenya, and poses a threat of introduction into other countries where it does not presently occur. As with other tephritid fruit fly species, establishment of B. latifrons can have significant economic consequences, including damage and loss of food production, as well as requirements for implementation of costly quarantine treatments to permit export of commodities susceptible to infestation by B. latifrons. In order to avoid these adverse economic consequences, one needs to prevent the entry, establishment and spread of B. latifrons into a new habitat. To successfully achieve this, an accurate knowledge of the fly’s host plants is essential. Cognizant of this need, we prepared, and present here, a worldwide list of host plants for B. latifrons, with annotations on reported laboratory and field infestation data. Overall, a total of 59 plant species from 14 plant families are identified as hosts of B. latifrons, based on reported field infestation data

Translational regulation contributes to the elevated CO2 response in two Solanum species.

Understanding the impact of elevated CO2 (eCO2 ) in global agriculture is important given climate change projections. Breeding climate-resilient crops depends on genetic variation within naturally varying populations. The effect of genetic variation in response to eCO2 is poorly understood, especially in crop species. We describe the different ways in which Solanum lycopersicum and its wild relative S. pennellii respond to eCO2 , from cell anatomy, to the transcriptome, and metabolome. We further validate the importance of translational regulation as a potential mechanism for plants to adaptively respond to rising levels of atmospheric CO2

Genes Encoding Recognition of the Cladosporium fulvum Effector Protein Ecp5 Are Encoded at Several Loci in the Tomato Genome

The molecular interactions between tomato and Cladosporium fulvum have been an important model for molecular plant pathology. Complex genetic loci on tomato chromosomes 1 and 6 harbor genes for resistance to Cladosporium fulvum, encoding receptor like-proteins that perceive distinct Cladosporium fulvum effectors and trigger plant defenses. Here, we report classical mapping strategies for loci in tomato accessions that respond to Cladosporium fulvum effector Ecp5, which is very sequence-monomorphic. We screened 139 wild tomato accessions for an Ecp5-induced hypersensitive response, and in five accessions, the Ecp5-induced hypersensitive response segregated as a monogenic trait, mapping to distinct loci in the tomato genome. We identified at least three loci on chromosomes 1, 7 and 12 that harbor distinct Cf-Ecp5 genes in four different accessions. Our mapping showed that the Cf-Ecp5 in Solanum pimpinellifolium G1.1161 is located at the Milky Way locus. The Cf-Ecp5 in Solanum pimpinellifolium LA0722 was mapped to the bottom arm of chromosome 7, while the Cf-Ecp5 genes in Solanum lycopersicum Ontario 7522 and Solanum pimpinellifolium LA2852 were mapped to the same locus on the top arm of chromosome 12. Bi-parental crosses between accessions carrying distinct Cf-Ecp5 genes revealed putative genetically unlinked suppressors of the Ecp5-induced hypersensitive response. Our mapping also showed that Cf-11 is located on chromosome 11, close to the Cf-3 locus. The Ecp5-induced hypersensitive response is widely distributed within tomato species and is variable in strength. This novel example of convergent evolution could be used for choosing different functional Cf-Ecp5 genes according to individual plant breeding needs

Effect of cadmium hyperaccumulation on antioxidative defense and proline accumulation of Solanum nigrum

Changes in cadmium (Cd) accumulation, the activity of antioxidant enzymes including superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and the concentrations of malondialdehyde (MDA), chlorophyll and free proline in Solanum nigrum, Cd-hyperaccumulator were examined and compared with a non-hyperaccumulator, Solanum lycopersicum L. It was indicated that the root and leaf SOD, POD and CAT activities of S. nigrum were significantly higher than that of S. lycopersicum. In comparison with S. nigrum, there was a decrease in the growth and chlorophyll content, and an increase in MDA concentrations in the roots and leaves of S. lycopersicum. Although lipid peroxidation was promoted in both S. nigrum and S. lycopersicum by high Cd stress, higher increase occurred in the tissues of S. lycopersicum. The concentration of free proline in the leaves and roots of S. nigrum was higher than those in S. lycopersicum across all the Cd treatments. These results showed that the Cdhyperaccumulator, S. nigrum had a greater capacity than S. lycopersicum to adapt to oxidative stress caused by Cd.Key words: Solanum nigrum L., hyperaccumulator, antioxidative defense, proline, cadmium

アントシアニジン合成系遺伝子DFRの系統解析

Plants have various color pigments. Many plants have fruits and flowers of vivid colors such as orange, red, purple and blue. Anthocyanins with anthocyanidins as aglycone are one group of plant pigments. Each type of anthocyanidins is determined by the substrate specificity of dihydroflavonol 4-reductase (DFR) in its biosynthetic pathway and has a major influence on the determination of plant color. We performed a phylogenetic analysis of DFR genes, which are key enzymes of this anthocyanidin biosynthesis pathway. We collected 170 DFR clones in various plants by browsing database (NCBI). The collected DFRs were classified into ten groups according tosequence similarity. The consensus sequences within each group were aligned, and amino acids involved in the responsible region for determination of the substrate specificity of DFR have been shown. In addition, DFR's intron sites were highly conserved. These results would be useful to unveil the relationship between DFR and plant pigments

Morphological characters, occurrence and distribution among members of the family Solanaceae in parts of the Niger Delta Ecological Zone

This study investigated a comparative micro-morphological features of 14 species in the family Solanaceae, using trichome and stomatal complements in delimitation of species and genera within the taxon, family. The genus Solanum L. is the largest among the genera in Solanaceae. Solanum aethiopicum Linn. Solanum macrocarpon Linn. Solanum torvum Swartz. Solanum anomalum Thonn. Solanum erianthum D. Don, are covered with stellate trichomes. While Solanum nigrum Linn., Solanum lycopersicum Linn., Solanum incanum Linn., Datura spp., Schwenckia spp., Capsicum spp., Physalis spp. have simple uniseriate trichomes. S. aethiopicum Linn. S. torvum Swartz. S. lycopersicum Linn, and Physalis micrantha Linn, revealed higher trichome indices. In most species, these trichomes are not visibly observed with the naked eyes. While in some others such as in S. torvum and S. lycopersicum the trichomes are observable on the plants. Glandular hairs are also present in Solanaceae. Stomata is amphistomatic, types commonly observed are: anisocytic and anomocytic, while paracytic and tetracytic stomata are sometimes revealed in stem epidermis in Solanaceae. The usefulness of trichome and stomatal complements in species and generic taxa are recommended as pertinent characters for classification in Solanaceae and their density may vary from one ecological zone to another.Keywords: Solanaceae, Solanum, Stomata, trichomes, Complements, Comparativ