Pomelo Citrus Research Articles

SWOT-AHP integration for determining development strategy of Pangkep Pomelo Citrus Agro-industry

SWOT-AHP integration for determining development strategy of Pangkep Pomelo Citrus Agro-industry

Identification of Some Species of the Family Coccidae that Infest Fruit Orchards in Syria

Saleh, A.T. and A.M. Basheer. 2024. Identification of Some Species of the Family Coccidae that Infest Fruit Orchards in Syria. Arab Journal of Plant Protection, 42(2): 174-183. https://doi.org/10.22268/AJPP-001224 Soft scale insects are serious plant pests, are often small and highly cryptic. These pests are economically important in agriculture. Insect samples and infested plant parts were collected during the period April to June 2016 and 2017 from three locations (Al-Sanobar, Daba, and Jaba) and then brought to the Biological Control Studies and Research Center (BCSRC). The following soft scale insects of the order Coccomorpha and family Coccidae were identified: Coccus pseudomagnoliarum Kuwana, in Al-Sanobar and Dabba in Lattakia governorate in Java orange orchards, Saissetia oleae Olivier and C. pseudomagnoliarum Kuwana in Pomelo citrus tree in Daba locality, Sphaerolecanium prunastri Fonscolombe at the third site Jaba, Quneitra governorate, in almond orchards, and to our knowledge is the first record in Syria. Identification and characterization of the soft scale insects was based on microscopic characters of adult female using slide-mounted specimens. Identification of pests is essential for the implementation of biological control programs. Keywords: Coccidae, soft scale insects, Syria

Community Empowerment Through Digital Literacy in Marketing Processed Pomelo Oranges in Attangsalo Village, Ma'rang District, Pangkep Regency

As a pomelo agricultural center, the Attangsalo Village faces challenges in marketing processed oranges that have not reached their optimal potential. Therefore, it is essential to empower the community through digital literacy training for marketing processed pomelo oranges in Attangsalo Village, Ma'rang District, Pangkep Regency. The goal of this program is to promote the marketing of processed pomelo oranges within the pomelo citrus farming businesses. This initiative involved approximately 30 participants, representing groups of housewives, and was carried out through participatory surveys, observations, lectures, discussions, and hands-on practice. The results of the program implementation demonstrate the participants' dedication and enthusiasm during each training session. Several technical aspects, including the utilization of social media for marketing processed pomelo oranges, were comprehensively understood by the program partners. Furthermore, participants were able to apply the training during the practical learning sessions.

Analysis of stem rot disease severity on Pomelo (Citrus maxima) plantation in Pangkep Regency, South Sulawesi

AbstrackPamelo (Citrus maxima) is native to Southeast Asia, and the contribution of South Sulawesi nationally as a producer ranks first at 30.76%. The purpose of this study was to determine the intensity of stem rot disease on Pomelo in Ma’rang, Labakkang, and Segeri Districts of Pangkep Regency. After calculating the disease severity, samples were taken on the symptomatic tissue, then the disease-causing pathogens were isolated and purified, followed by microscopic observation at the Laboratory of Pest and Plant Diseases, Hasanuddin University. The results showed that the highest stem rot disease intensity was in Ma’rang District on red and white Pomelo varieties at 53% and 44%, followed by Labakkang District at 33% on red Pomelo and 26% on white Pomelo. The lowest disease severity was in Segeri District with 30% on red and 24% on white Pomelo. Pomelo citrus production in Ma’rang District was 92.72 tons/ha, Labakkang 213.51 tons/ha, and Segeri District 259.40 tons/ha. These data indicate that the intensity of disease severity and land conditions affect the production of Pomelo in the three sub-districts observed.

Physiological Variables Influenced by 'Candidatus Liberibacter asiaticus' Infection in Two Citrus Species.

'Candidatus Liberibacter asiaticus' is the bacterium associated with the citrus disease known as huanglongbing (HLB). This study evaluated the influence of 'Ca. L. asiaticus' infection on a number of key plant physiological variables concerning photosynthesis, cell integrity, reactive oxygen species scavengers' activity, and osmoregulation of two different species of citrus-the pomelo Citrus maxima and the mandarin C. reticulata 'Tankan'-relative to their measured 'Ca. L. asiaticus' infection load. Results indicated that all measured physiological variables except soluble sugar were affected by increased 'Ca. L. asiaticus' infection titers, wherein the variety C. maxima proved overall more resistant than C. reticulata. 'Ca. L. asiaticus' infection was linked in both plants to decrease in chlorophyll concentration, cell membrane permeability, and malondialdehyde, as well as increased free proline and starch contents. Chlorophyll fluorescence measurements taken 9 months after grafting the mandarin C. reticulata with 'Ca. L. asiaticus' scions revealed a significant decrease in the photosynthesis variables maximum photochemical quantum yield of photosystem II (PSII), effective photochemical quantum yield of PSII, and coefficient of photochemical fluorescence quenching assuming interconnected PSII antennae, whereas nonphotochemical fluorescence quenching increased significantly; C. maxima plants, on the other hand, did not show significant differences until the 12th month from infection exposure. The variables superoxide dismutase, catalase, peroxidase, and soluble protein initially increased and later decreased. In addition, progression of 'Ca. L. asiaticus' replication in both citrus species was accompanied by rapid changes in three reactive oxygen species scavenging enzymes in C. maxima, while the pattern was different in C. reticulata. We hypothesize that the observed interspecific differences in physiological change are related to their relative resistance against 'Ca. L. asiaticus' infection. These results provide a scaffold for better describing the pathogenesis, selecting the most resistant breeds, or even validating pertaining omics research; ultimately, these detailed observations can facilitate the diagnosis of 'Ca. L. asiaticus' infection.

Reducing Macronutrients and Increasing Micronutrient Fertilizers Are Key to Improving the Quality of Pomelo Citrus grandis (L.) Osbeck Cv. “Guanxi”

Due to long-term excessive fertilization, the fruit quality of the Guanxi pomelo (Citrus grandis) has been declining. The classification of fruit quality and its relationship with nutrients in soils and trees were studied to declaim the characteristics of nutrients in Guanxi pomelo orchards, ultimately guiding the fertilization for high-quality fruit production. By cluster analysis, 281 samples were grouped into four clusters. High-quality fruit (HF) showed a gourd shape with moderate weight size, high sweetness, edible rate (ER) up to 73%, and vitamin C content over 40 mg/100 g. Compared to sub-quality fruit (SF), common fruit (CF), and inferior fruit (IF), the content of magnesium (Mg) in the leaves of HF was 11.76, 11.76, and 18.75% higher, while the content of iron (Fe) was 6.45, 5.76 and 10.97% higher, respectively. Meanwhile, the contents of Zinc (Zn, 8.51, 6.44, and 11.22% higher than SF, CF, and IF, respectively) and Boron (B, 13.47, 13.83, and 25.40% higher than SF, CF, and IF, respectively) were also found to increase. However, the contents of Mn (35.34, 27.51, and 25.53% higher) and Cu (31.90, 31.99, and 5.64% higher) in IF were significantly higher than in HF, SF, and CF. Acid soils (4.24–4.40) with low OM content (23.00–26.71 g kg−1) led to an imbalance uptake of nutrients of citrus, ultimately resulting in poor quality. These results indicated that farmers should reduce the application of nitrogen (N), phosphorus (P), and K fertilizer and pesticides and increase micronutrient and organic fertilizer, which provides a theoretical basis for scientific fertilization to improve the fruit quality of Guanxi pomelo (Citrus grandis) of Pinghe County.

Application of Trichoderma as an Alternative to the use of Sulfuric Acid Pesticides in the Control of Diplodia Disease on Pomelo Citrus

This study aims to determine the ability of Trichoderma asperellum Tc-Pjn-02 compared to sulfuric acid pesticides in controlling the disease stem rot Diplodia on Pomelo citrus (Citrus maxima) caused by Botryodiplodia theobromae Pat. The research was conducted at Balai Penelitian Tanaman Buah Tropika Kebun Percobaan Kraton-Pasuruan, East Java Province, and the Laboratory of Microbiology and Biotechnology of Universitas Muhammadiyah Sidoarjo in February-April 2020. Trichoderma and sulfuric acid were applied in an aqueous paste formulation each of 10 units of diseased plants with rotten stems which were randomly selected as samples. The data from the observations were tested using the t-test at the real level of 5%. The results showed that Trichoderma sp. had a higher ability in suppressing pathogen attack compared to sulfuric acid which was able to heal rotten wounds on the stalks affected by 41.95% and 26.74%, respectively.

Effects of Vacuum Concentration on Color, Polyphenol and Flavonoid Contents and Antioxidant Activity of Pomelo Citrus maxima (Burm. f.) Merr. Juice

Pomelo (Citrus maxima (Burm. f.) Merr). juice is known as an enriched source of antioxidants and nutrients. It is therefore necessary to develop a preservation method for freshly prepared juice. This study aims to determine the effect of the vacuum concentration process on the change in color, bioactive compounds and antioxidant activity of pomelo juice. High pressure showed negligible effects on color. However, longer heating time seemed to cause browning in juice. In comparison with the fresh sample, total color difference (TCD) value of the treated sample was 6.73 ± 0.58 after 150 min of heating at 85°C. The total polyphenol content (TPC) values in the sample also increased with longer heating time or increased pressure. The total flavonoid content (TFC) seemed to be non-responsive to changes in heating time and pressure but was closely related to total soluble solid. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and 2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonate) (ABTS) of pomelo juice are affected by heat and, to a lesser extent, by pressure. The changes caused by the application of vacuum dehydration in the juice texture resulted in a higher water loss and higher sugar content (52.92 ± 0.79 °Brix).

Effects of microwave extraction conditions on polyphenol content and antioxidant activity of pomelo extract (Citrus maxima (Burm.)Merr.)

The albedo, white peel of pomelo Citrus maxima (Burm.)Merr., is by-product of food processing, and has polyphenol and antioxidant activity. However, there are not many studies on polyphenol from pomelo peel in Vietnam by microwave extraction. Microwave-assisted extraction helps more efficient heating, faster energy transfer, increasing or decreasing temperature control, saving solvent and cost to extract active ingredients from plant materials. This research applied microwave extraction to extract polyphenol from pomelo Citrus maxima (Burm.)Merr. The factors that affected the extraction process such as solvent concentration, microwave power, extraction time and material to solid ratio were investigated. The results obtained that the highest polyphenol content (2.46 gGAE/L) and antioxidant activity (1325.85 µmolTE/L) with ethanol concentration of 60%, microwave power of 300W, microwave-assisted time of 2 minutes, and material to solvent ratio of 1:30.

POTENSI AKTIVITAS ANTIOKSIDAN EKSTRAK ETANOL DAN FRAKSI N-HEKSAN BUAH JERUK PAMELO (Citrus maxima (Burm) Merr) ASAL KABUPATEN PANGKEP

Pomelo citrus (Citrus maxima (Burm) Merr) is a fruit plant that has the potential to be developed for health. Pomelo fruit contains lycopene, flavonoids and vitamin C which can provide antioxidant activity. The purpose of this study was to determine the potential antioxidant activity of ethanol extract and fraction of n-hexane of pomelo citrus using quercetin as a comparison. Extraction of pomelo citrus fruit using the maceration method with liquid-liquid fractionation using water and n-hexane (1: 3 v / v). Testing of antioxidant activity using the DPPH (1,1-Diphenyl-2-picrylhidrazil) method is based on the ability of the sample to capture DPPH free radicals which are characterized by purple to yellow discoloration and a decrease in the absorbance value of DPPH which has reacted with samples in certain concentrations. Absorbance measurements using a UV-Vis spectrophotometer at a wavelength of 514,942 nm. The results showed that the IC50 value of quercetin was 6.55 µg / mL which was a strong antioxidant, while the IC50 value of the ethanol extract of pomelo citrus fruit was 2882.26 µg / mL and IC50 value of the n-hexane fraction of pomelo orange was 3668,44 µg / mL which is a weak antioxidant category. Kata kunci : Antioxidants, Ethanol Extract, n-Hexane Fraction, Pomelo citrus (Citrus maxima (Burm) Merr

Pomelo Citrus grandis (L.) osbeck peel as an economical alternative substrate for fungal pectinase production

Polygalacturonase production by Aspergillus niger LFP-1 was studied in solid state fermentation (SSF) using pomelo (Citrus grandis) peel as a substrate. This local agricultural waste product is rich in lignocellulolytic material, including pectin, which can act as an inducer of pectinase production. Using the parameters of 5 g of 0.75 mm (particle size) pomelo peel as a substrate, moisture content ratio of 1:1 (w/v), inoculum size of 1×107 spores/mL, cultivation temperature of 30°C, and no mixing, static fermentation conditions with addition of 1.2% ammonium nitrate produced the highest polygalacturonase production rate of 8.90 U/g of substrate and a fungal growth rate of 2.07mg of glucosamine/g of substrate on day 5 of cultivation. A large increase (1,434.5%) in enzyme production occurred after improvement of the growth parameters. Under optimum bioprocess conditions, pomelo peel can be used as solid substrate for production of pectinase.