Vertical farming is a new agricultural system which aims to utilize the limited access to land, especially in big cities. Vertical agriculture is the answer to meet the challenges posed by land and water shortages, including urban agriculture with limited access to land and water. This research study uses the Preferred Reporting for Systematic Review and Meta-analysis (PRISMA) item as one of the literary approaches. PRISMA is one way to check the validity of articles for a literature review or a systematic review resulting from this paper. One of the aims of this study is to review a survey of scientific literature related to vertical farming published in the last six years. Artificial intelligence with machine learning, deep learning, and the Internet of Things (IoT) in supporting precision agriculture has been optimally utilized, especially in its application to vertical farming. The results of this study provide information regarding all of the challenges and technological trends in the area of vertical agriculture, as well as exploring future opportunities.

Post-harvest treatment of Amorphophallus muelleri Blume (porang) tubers carried out by Indonesian farmers is slicing tubers into chips, drying, exporting, or processing them to a porang flour before export. To increase the economic value of porang tuber, it can be directly extracted to obtain glucomannan. Glucomannan is a polysaccharide that has many benefits. This work investigated the simple extraction method to produce high purity of glucomannan from fresh porang tubers and study the physicochemical properties of glucomannan. Sliced porang tuber repeatedly (three times) extracted by 60% ethanol (fixed concentration method). In addition, repeated extraction was conducted by varying ethanol concentrations (multilevel concentration method), in the first extraction, the sample was milled in 60% ethanol, then the precipitated sample was extracted again with 70% ethanol and finally extracted in 80% ethanol. Glucomannan with high purity (90.00%), whiteness degree (89.91), viscosity (14696.86 mPa.s), and a small number of impurities: ash (0.92%), fat (0.01%), protein (5.18%), without starch content was isolated by multilevel ethanol extraction method. By varying the concentration of ethanol, the impurities with different polarities could be dissolved effectively without heating, repetition of extraction, and further purification. FTIR spectra confirmed the presence of functional groups composing the glucomannan compound. XRD pattern showed that the extracted glucomannan had a more crystalline phase than commercial glucomannan. SEM results verified the purity of the appearance of glucomannan particles.

The corms and leaves of elephant foot yams (Amorphophallus paeoniifolius (Dennst.) Nicolson) are important foods in the local diet in many Asian regions. The crop has high productivity and wide agroecological adaptation and exhibits suitability for the agroforestry system. Although the plant is assumed to reproduce via panmixia, a comprehensive study on the genetic background across regions to enhance wider consumer palatability is still lacking. Here, ten informative microsatellites were analyzed in 29 populations across regions in India, Indonesia and Thailand to understand the genetic diversity, population structure and distribution to improve breeding and conservation programs. The genetic diversity was high among and within regions. Some populations exhibited excess heterozygosity and bottlenecking. Pairwise F_ST indicated very high genetic differentiation across regions (F_ST = 0.274), and the Asian population was unlikely to be panmictic. Phylogenetic tree construction grouped the populations according to country of origin with the exception of the Medan population from Indonesia. The current gene flow was apparent within the regions but was restricted among the regions. The present study revealed that Indonesia and Thailand populations could be alternative centers of the gene pool, together with India. Consequently, regional action should be incorporated in genetic conservation and breeding efforts to develop new varieties with global acceptance.

Previous studies revealed the impact growing location has on the quantity and quality of essential oils derived from numerous Citrus spp., except on the kaffir lime. This study aims to analyze the relationship shared by agroclimatic variables and soil-plant nutrient status to kaffir lime leaves essential oil yield and main composition. The experiment was conducted between February and April 2019 in four growing locations, namely Bogor (6°36′36″ S, 106°46′47″ E), West Bandung (6°48′12″ S, 107°39′16″ E), Pasuruan (7°45′5″ S, 112°40′6″ E) and Tulungagung (8°6′27″ S, 112°0′35″ E). The highest essential oil yield was obtained from Bogor (1.5%), while the lowest one was from Tulungagung (0.78%). The yield was positively and significantly correlated with the rainfall, soil organic carbon, soil pH, and macronutrient levels, i.e., nitrogen, phosphorus, and magnesium. Citronellal, the major component in metabolites’ profile of kaffir lime leaves essential oils, was significantly affected by the growing location. The absolute content of citronellal was positively and significantly correlated with the actual soil pH and leaf Ca content; furthermore, it negatively correlated with the leaf content of Fe, Mn, Zn, Cu. Pearson correlation analysis also showed (i) a negative significant correlation between the relative percentage of citronellol and annual rainfall intensity; (ii) a negative significant correlation between altitude and relative percentage of caryophyllene, and (iii) a positive significant correlation between the relative percentage of linalool and leaf K content.

Planting multifunctional trees (e.g., fruit species) in cities can promote genetic conservation, economic activity, ecosystem services, and social cohesion. However, in Indonesia, the relationship between the abundance of fruit tree species and different city characteristics, including their involvement in the national smart city project, is still unknown. In this study, published reports and field surveys were used to evaluate the fruit tree distribution and its relationship with the characteristics of 224 of 514 Indonesian cities in order to identify tree species for multifunctional city greenery. This is the first study on the distribution of fruit tree species at the national level. The study identified 151 fruit species of 90 genera and 40 families, including large-sized fruits, such as avocados, breadfruit, coconuts, durians, jackfruit, and mangos. On average, cities contained 54 tree species, of which 21 (38.9%) were fruit trees. These findings indicate that cities are important contributors to the genetic conservation of local fruit trees, which can be further evaluated as new city greenery. However, a city’s involvement in the smart city project bore no relationship (p > 0.05) with the number of identified fruit species. Conversely, non-fruit species tended to be more diverse in smart cities. Since the presence of fruit species is associated with the city population, geographic position, climate, altitude, and attitude towards the fragility of sustainable conservation, introducing and maintaining these species as city greenery requires advocacy to city stakeholders.