Physical-physiological quality and early performance of sorghum plants under different boron doses via seed

Boron (B) deficiency is commonly found in tropical crops, among which sorghum stands out for its limited yield under B shortage. However, as a micronutrient, the range between its adequate and toxic levels is narrow, thus fertilization should be cautiously applied. Our goal was to evaluate the physiological and physical quality, as well as early performance, of grain sorghum seedlings under different B doses applied via seeds. Treatments consisted of six doses of boric acid (0.0, 2.5, 5.0, 7.5, 10.0, and 12.5 g Kg-1 seeds) plus a control (uncoated seeds). Boron doses were applied to seeds by coating, in which dolomitic limestone and glue were used for pellet formation. Coated seeds were assessed for physical, physiological, and nutritional characteristics in the laboratory, and early seedling performance was evaluated in a greenhouse. Seed tests were carried out in a fully randomized design, while seedling evaluations were carried out in a randomized block design. Boron application to seeds had no significant effect on seed physical characteristics, despite increases in coated seed sizes. Boron doses had a negative effect on the length and dry mass accumulation of both plant shoot and root. Seed-applied B accumulated mainly in roots and significantly interfered with Ca and Mg accumulations in sorghum seeds, shoots, and roots.

Selective Thermotolerant Lactic Acid Bacteria Isolated From Fermented Juice of Epiphytic Lactic Acid Bacteria and Their Effects on Fermentation Quality of Stylo Silages

The aim of the present study was to isolate and identify lactic acid bacteria (LAB) from fermented juice of tropical crops such as Napier grass, Ruzi grass, Purple guinea grass, Stylo legume, and Leucaena and their application to improve the quality of tropical crop silage. Fifteen strains of LAB were isolated. The LAB strains were Gram-positive and catalase-negative bacteria and could be divided into three groups, i.e., Pediococcus pentosaceus, Lactiplantibacillus (para)plantarum, and Limosilactobacillus fermentum according to the biochemical API 50CH test. Based on the analysis of 16S rRNA sequence, the strains isolated in the group L. (para)plantarum were distinguished. Two isolates (N3 and G4) were identified as Lactiplantibacillus plantarum. Three isolates (St1, St2, and St3) were identified as L. paraplantarum. In addition, the identification of other isolates was confirmed in the group P. pentosaceus (R1, R4, R5, R8, R11, and L1) and the group L. fermentum (N4, G6, G7, and N4). All selected strains were able to grow at 50°C. All LAB strains showed antimicrobial activity against Escherichia coli ATCC 25922, Shigella sonnei ATCC 25931, Pseudomonas aeruginosa ATCC 27853, and Bacillus cereus ATCC 11778. Four selected LAB strains (St1, St3, N4, and R4) were tested for their capacity to successfully ensile Stylo legume (Stylosanthes guianensis CIAT184). Stylo silages treated with LAB were well preserved, the NH3–N and butyric acid contents were lower, and the lactic acid content was higher than those in the control (p < 0.05). The acetic acid content was the highest in R4-treated silage among the treatments (p < 0.05). The crude protein (CP) content of St1-silage was significantly (p < 0.05) higher than the others. The inoculation of thermotolerant LAB selected from fermented juice of epiphytic lactic acid bacteria (FJLB) was found to be highly instrumental to obtain well-preserved silage from the Stylo legume.

Mimosa pudica (sensitive plant).

M. pudica is an annual or biannual sub-woody plant native to South America. It was introduced outside of its native range as an ornamental species, and is still available for sale today. This species is typically present in disturbed areas in much of the tropics where it has naturalized. It can be readily and accidentally dispersed thanks to its propagules that stick to mammals' hairs and human clothing. M. pudica can become extremely weedy in disturbed sites, often forming monotypic ground cover, and is a major weed of many tropical crops. It is classified as invasive in a wide range of countries in Asia and the Pacific and is regarded as an undesirable import in to Florida, USA and Australia (ISSG, 2017). It is also reported as invasive in Burundi, Kenya, Malawi, Tanzania and Uganda.

The Geological Heritage of Salobreña (South Spain): example of a touristic area

Salobreña consist of a touristic area with a typical Andalusian white town built on a hill and crowned with a Castle from the medieval era of Moors occupation. The urban area is bordered by fields of tropical crops and fruit trees that, together with its location by the sea, confer on Salobreña a beautiful postcard. These features, as a whole, are an attraction for visitors. Although the authorities are very interested in developing the beach tourism and displaying and protecting the historical center of the town, the interest in geological heritage is negligible. So, this paper tries to expose and evaluate the sites of geologic interest recognizable in the area, so that not only tourists and visitors, but also students, are offered more attractions for their visits. 30 sites are proposed as suitable to be considered as geological heritage, organized in three accessible walking itineraries named respectively: Urban, Panoramic and Littoral georoutes. The selected sites display a great variety of geological typologies as structural geology, stratigraphy, sedimentology, geomaterials, petrology, mineralogy, geomorphology and hydrogeology-hydraulics. Avoiding subjectivity, the sites and georoutes have been classified and ranked with a numerical methodology based on recent literature. The Scientific Value (SV), Potential Educational Value (PEV), Potential Touristic Value (PTV) have been quantified by using several criteria in each case. This allows visitors and teachers to select the most suitable route according to their goals. The Degradation Risk (DR) has also been evaluated, giving key geo-conservation actions. This plan can be presented to political and technical managers from Salobreña Town. Finally, some actions are proposed for better conservation of the sites but also to contribute to education and promote cultural tourism. These actions would also favor educational activities for students of all levels in earth science subjects, but also increase economic activity and sustainable development in the area by incorporating cultural visitors.

Development of Single Nucleotide Polymorphism (SNP) Markers in Tropical Crops

Understanding genetic diversity, association studies, evolution analysis, quantitative trait loci, marker-assisted selection and genome-wide association in tropical crops are important for improving plant characteristics in order to increase food sustainability in tropical countries. Single nucleotide polymorphism (SNP) marker is becoming the most popular molecular marker for those studies. By using SNP marker, genes associated with important traits can be identified efficiently compared to the other molecular markers. This review describes about how SNP can be discovered in the plant genomes and the application of SNP in plant breeding, especially in tropical crops such as rice, maize, peas, potato, tomato, cassava, taro, etc. Keywords: food sustainability, plant breeding, SNP marker, tropical crops

Cocoa pod husks as potential sources of renewable high-value-added products: A review of current valorizations and future prospects

Cocoa is among the most cultivated and important tropical crops in the world, and it is economically viable in the agro-pastoral systems of tropical Africa. Further, the amount of cocoa residue is steadily increasing due to the strong worldwide demand for chocolate products. This review of cocoa residue found that an average of 18 publications per year were published in the last 10 years. The most common type of publication on cocoa pod husks (CPH) was newspaper articles, which comprised 50% of the publications. This review examines the use of CHP in sustainable development, agrochemical materials, and agro-materials through their potential valorizations into high value-added products. Indeed, CPH is an abundant, accessible, and renewable resource of bioproducts, dietary fibers, nutraceuticals, functional foods, pectin, antioxidant compounds, theobromine, and minerals. Potential food applications of CPH include the production of flavor compounds, gums, texturing agents, and others. The production of biomaterials for food and non-food use, biofuels, and organic acids, such as lactic acid (the polymerization of which produces the PLA used in bioplastic production), are several potential areas for the biotechnological development of CPH and its fractions.