Isolation of Beauveria Strains and Their Potential as Control Agents for Lema bilineata Germar (Coleoptera: Chrysomelidae)

Lema bilineata Germar (Coleoptera: Chrysomelidae) was recently reported to damage Physalis peruviana crops in Brazil. Given the potential for inflicting damage on other Solanaceae species and the lack of alternatives for controlling this pest, we assessed the pathogenicity of 15 Beauveria isolates against L. bilineata adults in vitro. In addition, three of these isolates were tested for their ovicidal effect against L. bilineata eggs. Fungal strains were isolated from mummified corpses of L. bilineata collected in a non-commercial field in Paraná, Brazil. The isolates were identified as Beauveria bassiana using molecular markers. Lema bilineata adults were susceptible to conidial suspensions of all these isolates at a concentration of 108 conidia mL−1. Deaths caused by fungal extrusion were confirmed. Three strains were found to be more virulent against L. bilineata adults and showed ovicidal effects. This is the first study on entomopathogenic fungi isolated from dead insects collected from P. peruviana crops and tested against L. bilineata carried out in Brazil. The results obtained in the laboratory indicate the high potential of the use of three B. bassiana strains against L. bilineata as a biocontrol agent.

Phytophthora infestans: An Overview of Methods and Attempts to Combat Late Blight

Phytophthora infestans (Mont.) de Bary is one of the main pathogens in the agricultural sector. The most affected are the Solanaceae species, with the potato (Solanum tuberosum) and the tomato (Solanum lycopersicum) being of great agricultural importance. Ornamental Solanaceae can also host the pests Petunia spp., Calibrachoa spp., as well as the wild species Solanum dulcamara, Solanum sarrachoides, etc. Annual crop losses caused by this pathogen are highly significant. Although the interaction between P. infestans and the potato has been investigated for a long time, further studies are still needed. This review summarises the basic approaches in the fight against the late blight over the past 20 years and includes four sections devoted to methods of control: (1) fungicides; (2) R-gene-based resistance of potato species; (3) RNA interference approaches; (4) other approaches to control P. infestans. Based on the latest advances, we have provided a description of the significant advantages and disadvantages of each approach.

POLLEN MORPHOLOGY OF LYCIUM (SOLANACEAE) SPECIES IN IRAN

Lycium (Solanaceae) has more than 100 species in arid and semi-arid parts of the world. In Iran, this medicinal plant is represented by 6 species, on which no palynological study has been conducted. Pollen morphology of 7 taxa are considered for the first time to evaluate the species relationships based on palynological data. Observations were made by use of Scanning electron microscopy on untreated pollen grains. Multivariate statistical analyses were carried out for qualitative and quantitative pollen features in the species studied. Results show that all pollen grains were monad, isopolar, zonotricolporate in prolate and preprolate shape. Exine sculpture was of striate and regulate patterns. Variations in pollen grains are considered to overcome the identification problems in species separation in morphologically similar taxa in this genus in Iran. The importance of pollen features in delimitation in some genera of Solanaceae was previously proven and the present study elucidates that some features as exine sculpture and some quantitative characters are of diagnostic importance in Lycium species native to Iran.

Living in extreme environments: distribution of Lycium humile (Solanaceae), an endemic halophyte from the Altiplano-Puna region, South America

Very few Solanaceae species are able to grow in saline soils; one of them is Lycium humile. This species is endemic to the Altiplano-Puna region (Central Andes, South America) where there are multiple extreme environmental conditions such as hypersaline soils. Here we present an updated description and distribution of L. humile including its new record for Bolivia at the edges of “Salar de Uyuni”, the largest salt flat in the world; we discuss its ecological role in saline environments by analyzing soil salinity and cover-abundance values ​​of the studied sites. According to IUCN criteria, we recommend a category of Least Concern for L. humile, but the growing development of lithium mining in saline environments of the Altiplano-Puna region may potentially threaten exclusive communities.

Megalopodidae (Insecta, Coleoptera): new occurrence and host plant records for Brazil

The Brazilian Megalopodidae fauna consists of 147 species from 11 genera, of which Mastostethus Lacordaire is the most diverse, representing about half of the species. Nevertheless, knowledge about species distributions and their relationships with host plants is still scarce. Since this group has endophytic immatures and bore into branches, they are economically important as they mainly damage Solanaceae species. Thus, this study sought to determine the Megalopodidae species that occur in forest fragments of southwestern and western Paraná and associate them with their host plants. For this purpose, we used material collected with Malaise traps and active manual sampling to determine associations with host plants. A total of 170 specimens of 11 species were sampled, of which Pseudhomalopterus carinatus Pic, 1920 was the most abundant and collected in all fragments. Four species were sampled exclusively through manual collections and associated with their host plants, all of which were new association records for Brazilian megalopodides. Mastostethus pantherinus Lacordaire, 1845 was associated with an Asteraceae for the first time. Additionally, Mastostethus minutus Monrós, 1947 is a new record for Brazil.

Transcriptome-Based Identification and Functional Characterization of NAC Transcription Factors Responsive to Drought Stress in Capsicum annuum L.

Capsicum annuum L. is one of the most cultivated Solanaceae species, and in the open field, water limitation leading to drought stress affects its fruit quality, fruit setting, fruit size and ultimately yield. We identified stage-specific and a common core set of differentially expressed genes, following RNA-seq transcriptome analyses of a breeding line subjected to acute drought stress followed by recovery (rewatering), at three stages of plant development. Among them, two NAC transcription factor (TF) genes, i.e., CaNAC072 and CaNAC104, were always upregulated after drought stress and downregulated after recovery. The two TF proteins were observed to be localized in the nucleus following their transient expression in Nicotiana benthamiana leaves. The expression of the two NACs was also induced by NaCl, polyethylene glycol (PEG) and abscisic acid (ABA) treatments, suggesting that CaNAC072 is an early, while CaNAC104 is a late abiotic stress-responsive gene. Virus-induced gene silencing (VIGS) of CaNAC104 did not affect the pepper plantlet’s tolerance to drought stress, while VIGS of CaNAC072 increased drought tolerance. Heterologous expression of CaNAC072 in Arabidopsis thaliana as well as in plants mutated for its homolog ANAC072 did not increase drought stress tolerance. This highlights a different role of the two NAC homologs in the two species. Here, we discuss the complex role of NACs as transcriptional switches in the response to drought stress in bell pepper.

All-Flesh Tomato Regulated by Reduced Expression Dosage of AFF Through a Promoter SV Mutation

The formation of locule gel is an important process in tomato and a typical characteristic of berry fruit. In this study, we collected a tomato natural mutant that produces all-flesh fruits (AFF) in which the locule tissue remains in a solid state during fruit development. We built genetic populations to fine-map the causal gene of the AFF trait and identified the gene AFF (SlMBP3) as the locus conferring the locule gel formation. We determined the causal mutation as a 416-bp deletion that occurred in the promoter region of AFF and reduced its expression dosage. The 416-bp sequence is highly conserved among Solanaceae species, as well as within the tomato germplasm. Furthermore, with the BC6 NIL materials, we revealed that the reduced expression dosage of AFF did not impact the normal development of seeds but produced unique non-liquefied locule tissue, which was distinct from that of normal tomatoes in terms of metabolic components. We further revealed the importance of AFF gene in locule tissue liquefaction through combined analysis using mRNA-seq and metabolomics. Our findings provide clues to investigate fruit type differentiation in Solanaceae crops and also contribute to the application of the AFF gene in tomato breeding programs.

Genome assembly of primitive cultivated potato Solanum stenotomum provides insights into potato evolution

Genetic diversity is the raw material for germplasm enhancement. Landraces and wild species relatives of potato, which contain a rich gene pool of valuable agronomic traits, can provide insights into the genetic diversity behind the adaptability of the common potato. The diploid plant, Solanum stenotomum (Sst), is believed to have an ancestral relationship with modern potato cultivars and be a potential source of resistance against disease. Sequencing of the Sst genome generated an assembly of 852.85 Mb (N50 scaffold size, 3.7 Mb). Pseudomolecule construction anchored 788.75 Mb of the assembly onto 12 pseudochromosomes, with an anchor rate of 92.4%. Genome annotation yielded 41,914 high-confidence protein-coding gene models and comparative analyses with closely related Solanaceae species identified 358 Sst-specific gene families, 885 gene families with expansion along the Sst lineage, and 149 genes experiencing accelerated rates of protein sequence evolution in Sst, the functions of which were mainly associated with defense responses, particularly against bacterial and fungal infection. Insights into the Sst genome and the genomic variation of cultivated potato taxa are valuable in elaborating the impact of potato evolution in early landrace diploid and facilitate modern potato breeding.