Taciane Finatto

Tomato cultivation in organic production systems faces production challenges related to the low availability of genotypes adapted to the particularities of this system. This study aimed to present a breeding program and select promising tomato lines for cultivation in an organic open-field system in Southern Brazil. Different combinations of crosses were obtained from three non-hybrid genotypes and one commercial hybrid, and the genotypes of interest were determined by visual selection. In the F6 generation, four parental genotypes (CH, GA, BGT_16 and BGT_37) and ten experimental lines (1731, 1732, 1733, 1724, 1725, 1716, 1717, 1718, 1729 and 17,210) were evaluated in open-field organic production management in a randomized complete block design with four replications. Various morpho-agronomic traits were evaluated, and nine traits of importance for the organic system were selected from a subset that underwent multicollinearity analysis. Using these traits, association analyses between traits, genetic diversity, and the Mulamba and Mock selection index were performed, focusing on the selection of superior traits such as commercial fruit production, soluble solids/titratable acidity ratio, foliage density, and a*/b* colour parameter ratio. Cluster analysis identified a promising cross between CH and BGT_37 for obtaining desirable genotypes. The selection index determined lines 1732, 1733, 1717, and 17,210 as the most promising for the breeding program's objectives, and 1733 stood out with satisfactory values for all traits with the highest economic weights for selection. By improving these lines, we aim to develop genotypes adapted to organic production with characteristics of interest to both farmers and the consumer market.

Arracacha is vegetatively propagated; thus, in vitro tissue culture combined with rooting and acclimatization is an alternative for acquiring high-quality disease-free plantlets. For in vitro propagation studies, three experiments were conducted. The first evaluated different combinations of plant growth regulators (PGRs): B5 medium formulation without a PGR, B5 + 0.2 mg·L⁻¹ 6-benzylaminopurine + 0.01 mg·L⁻¹ 1-naphthaleneacetic acid, and B5 + 0.3 mg·L⁻¹ 6-benzylaminopurine + 0.1 mg·L⁻¹ 1-naphthaleneacetic acid; this assay used three arracacha cultivars ('BRS Rubia 41', 'BRS Acarijó 56', and 'Amarela de Senador Amaral'). The second experiment evaluated the effect of photoperiod (10, 12, and 14 h) on three cultivars ('Amarela de Senador Amaral,' 'BRS Catarina 64', and 'BRS Rubia 41'). The third tested different concentrations of indolebutyric acid (IBA) (0.0, 3.0, 6.0, 9.0, 12.0 mg·L⁻¹) with and without activated charcoal (1.0 g·L⁻¹), and different formulations (B5 and ½ B5) supplemented with 0.3 mg·L⁻¹ 6-benzylaminopurine and 0.1 mg·L⁻¹ indolebutyric acid sealed with one of three different materials (parafilm, gauze, polyvinyl chloride). The culture medium with the highest shoot regeneration rate that was most favorable for in vitro establishment was B5 + 0.3 mg·L⁻¹ 6-benzylaminopurine + 0.1 mg·L⁻¹ 1-naphthaleneacetic acid. Photoperiod did not affect cultivar development, and the responses varied among cultivars. Activated charcoal did not improve the rooting rates. The culture medium with ½ B5 sealed with PVC promoted better in vitro rooting and hardening of arracacha.

Molecular markers are powerful tools for detecting genetic variation at the DNA level, offering a direct, reliable, and efficient approach for the characterization, conservation, management, and utilization of plant germplasm. Among these, Inter-Retrotransposon Amplified Polymorphism (IRAP) markers target the genomic regions between retrotransposon insertions, revealing polymorphisms based on insertion patterns. This study aimed to develop and validate new IRAP markers for the genetic characterization of common bean (Phaseolus vulgaris) genotypes. Twelve IRAP primers were designed based on LTR retrotransposon sequences identified in the P. vulgaris genome database and tested in a panel of 22 genotypes, including 11 landraces, 10 commercial cultivars, and one F₂ individual derived from a cross between cultivars IPR Andorinha and BRS Estilo. Genomic DNA was extracted from young leaves using a modified CTAB protocol, and PCR amplifications were performed using the newly designed primers. The average polymorphism rate among the markers was 90.67%, and the mean genetic similarity among the genotypes was 0.557. The polymorphic information content (PIC) values ranged from 0.086 (Pv_IRAP_8) to 0.500 (Pv_IRAP_10), with the most informative primers being Pv_IRAP_4, Pv_IRAP_6, Pv_IRAP_7, Pv_IRAP_9, and Pv_IRAP_10. High genetic similarity was observed between some landraces and commercial cultivars, suggesting redundancy within the germplasm collection and highlighting the importance of molecular tools in optimizing genetic resource management in common bean breeding programs.

A murcha bacteriana, causada por espécies fitopatogênicas do gênero Ralstonia, é uma das principais doenças do tomateiro. O complexo de espécies de Ralstonia solanacearum ocorre devido a variantes com alta diversidade em termos de adaptação a diferentes condições climáticas, variabilidade de hospedeiros e agressividade, características que interferem na recomendação para o controle da doença. Neste estudo foram analisados por métodos moleculares 26 isolados de R. solanacearum isolados de plantas de tomateiro cultivadas na região sudoeste do Paraná. Os isolados foram obtidos de plantas com sintomas de murcha cultivadas em sistema de cultivo protegido e campo aberto. Os iniciadores específicos 759/760 foram usados para confirmar que os isolados pertenciam ao complexo específico Ralstonia solanacearum e os iniciadores Nmult foram usados para identificar o filotipo. A análise de variabilidade foi realizada por BOX-PCR com o primer BOX-A1R para 19 isolados. Os vinte e seis isolados foram confirmados como Ralstonia solanacearum e pertencentes ao filotipo II. A comparação entre os padrões de bandas do DNA genômico amplificado por BOX-PCR demonstrou variabilidade molecular com a formação de oito grupos ao nível de 0,63 de similaridade. Esses resultados confirmam a predominância de R. solanacearum filotipo II no sudoeste do Paraná e auxiliam na tomada de decisões relacionadas ao manejo da doença, bem como no melhoramento genético para obtenção de cultivares resistentes.

As plantas alimentícias não convencionais (PANC) são plantas espontâneas ou cultivadas, capazes de ampliar as fontes de nutrientes disponíveis à população e promover a soberania e segurança alimentar. Apesar do potencial que as PANC representam, as espécies nativas do Brasil, em sua maioria, não fazem parte do grupo de alimentos mais consumidos no país. O objetivo do trabalho foi analisar o estado da arte das pesquisas acadêmicas relacionadas às PANC, utilizando uma análise bibliométrica de pesquisa e produção científica mundial a respeito do tema. Foram identificados 2.056 artigos provenientes de pesquisa, com 50 termos de busca, sendo que, desses, 26 retornaram resultados. Foi observado um aumento em publicações sobre o tema, em especial a partir de 1996. A fonte mais relevante sobre o tema é o Journal of Ethnobiology and Ethnomedicine. Os Estados Unidos ocupam o primeiro lugar em relação ao número de citações sobre a temática, e o Brasil ocupa a 28ª colocação. Palavras como wild, edible, plant, flowers, food, traditional, indigenous e plants foram as mais citadas em títulos dos artigos. Apesar do aumento das pesquisas acerca do tema, o cenário ainda é incipiente, considerando a grande quantidade de plantas compreendidas como “não convencionais” existentes.

Climate change alters regular weather seasonality. Corn is one of the main crops affected by irregular water regimes. Due to complications in decision-making processes related to climate change, it is estimated that planting corn outside the optimal window results in around USD 340 million in losses per year in the United States’ Corn Belt. In turn, exogenous plant growth regulators have been gaining prominence due to their potential to positively influence the morphology and physiology of plants under stress. This study was based on the hypothesis that the use of plant growth regulators can assist in mitigating the adverse effects of climate change on corn plants sown both inside and outside the recommended planting period. In this context, the effects of biostimulant application on gas exchange in corn plants sown within and outside the recommended period were evaluated. The experiment was carried out in randomized blocks in a 4 × 5 × 2 factorial scheme with four repetitions. These were four sowing times, the application of the biostimulants via seeds in five doses, and foliar applications (presence and absence). The biostimulant doses were 0.00, 6.25, 12.50, 18.75, and 25 mL kg⁻¹. The foliar application used a dose of 500 mL ha⁻¹. Only in the period (2017/2) higher doses of biostimulants indicated a decrease in the water use efficiency of plants, suggesting the need to evaluate this variable carefully. In this regard, future studies may investigate the ideal doses and application timings of biostimulants for different edaphoclimatic conditions. In general, the combined use of biostimulants on seeds and as a foliar treatment boosted physiological activity and stimulated photosynthetic processes in corn plants. Based on these data, plant regulators can be a useful tool to mitigate the adverse effects of climate change on corn plants sown inside and outside the planting period.

Due to the high value of the fruit, the European chestnut (Castanea sativa Mill.), usually grown in agroforestry systems, has been planted as a single species in orchards managed with increasingly intensive cropping practices, such as the regular use of fertilisers. This justifies research into establishing fertilisation programmes oriented towards ecological intensification. In this study, the results of fruit production, plant nutritional status and soil properties are reported from a field trial in which three NPK fertilisers (20:7:10, 13:11:21 and 7:14:14) and a control treatment were used. Chestnut yields did not vary significantly between treatments, although the mean values of the control showed a clear downward trend. N supplied by the fertilisers seems to have been the most important factor in the difference between the fertilised and control treatments, since leaf N concentrations were lower in the control and often below the lower limit of the sufficiency range. Soil inorganic N levels in the autumn, and tissue N concentrations of the herbaceous vegetation developing beneath the trees, indicated risks of N loss to the environment and highlighted the importance of this vegetation remaining during the winter. The chestnuts’ poor response to fertiliser applications was attributed to the buffering effect of the large perennial structure of the trees on the distribution of nutrients to the growing plant parts. In large trees, it seems appropriate to base the annual fertilisation plan on leaf nutrient concentration. Thus, farmers probably should avoid spending money on fertilizer applications as long as leaf nutrient concentrations do not approach the lower limits of sufficiency ranges.

In this study, the aim of this study was to identify the source of resistance using KASP markers developed for Rpp1 – Rpp5 and screening for resistance in field trials in F₂ populations. Ten F₂ soybean (Glycine max (L.) Merrill) populations derived from crosses between rust-susceptible (55I57RSF IPRO, 63I64RSF IPRO) and rust-resistant sources (PI 200492, PI 594538A, PI 587880A, PI 594723, PI 230970, PI 506764, PI 459025A and PI 200487) were evaluated. All F2 plants were individually evaluated in field conditions for ASR phenotypic reactions and classified according to sporulation level. KASP markers were developed according to assays associated with Rpp genes available at SoyBase. Based on a slight difference in map position and different phenotypic disease reactions of PI 200492, we suggest that PI 594723 carries a resistance gene Rpp1-b. The Rpp1-b gene from PI 594723 was mapped on Chr 18 in a 12.4 cM region. The PIs carrying Rpp1-b (PI 594723, PI 587880A, and 594538A) showed strong resistance to ASR compared to the lines carrying Rpp1 (PI 200492). A total of 26 KASP markers were significantly associated (P < 0.01) with ASR resistance. Among those, M1, M5, and M6 (Rpp1), M13 and M14 (Rpp2), M16, M17 and M20 (Rpp3), M25 and M26 (Rpp4), and M27 and M28 (Rpp5) have the potential to be used in marker-assisted selection strategies.

Food insecurity has increased over time, combined with contamination, environmental degradation, and declining human health. This shows that conventional forms of agriculture are neither sustainable nor viable, whether from an ecological or social perspective. The objective of the study was to present the state of the art on the use of Non-Conventional Food Plants - Panc, in agroecological systems and their relationship with the strengthening of food and nutrition sovereignty and security. For this, a narrative bibliographic review was carried out, with data collected on SciELO platforms, CAPES and Web of Science journals. In addition to the Google Scholar® website, academic works (dissertations and theses) and FAO (Food and Agriculture Organization of the United Nations) reports. It was found that agroecology, seen as a science, and able to support a transition to sustainable agriculture models, has contributed to sustainable rural development. One of the objectives of agroecology is the search for the increasing use of a greater diversity of plants that, in addition to the food purpose, represent a subsistence alternative for rural communities and that also can contribute to the region's economy, such as Non-Food Plants. Conventional – Panc. The study also reinforces that the production of Panc in agroecological-based systems contributes to food security. They are sustainable systems concerned with the environment and nutrition, ensuring the distribution of affordable and nutritious food, and managing natural resources to preserve ecosystems.