Sweet Orange Research Articles

Gibberellic acid mitigates Huanglongbing symptoms by reducing osmotic and oxidative stress in sweet orange

Huanglongbing (HLB; citrus greening disease) is presumably caused by the bacterium Candidatus Liberibacter (CLas). Here, we present evidence in terms of physiological, carbohydrate, transcriptome, phytohormones, and key enzyme activities behind the beneficial effect of gibberellic acid (GA3) in mitigating biotic (CLas-infection) and abiotic (osmotic) stresses in HLB-affected ‘Valencia’ sweet orange. For two consecutive years, non-fruiting leaves of untreated control tress accumulated ≈ 8 % higher fructose whereas fruiting leaves accumulated ≈ 10 % higher fructose and glucose compared to GA3 treated trees. Control trees also had higher starch (≈ 25 %) and callose (≈ 15 %) content than GA3 trees, which are indicators for osmotic stress, and CLas-induced plasmodesmata closure resulting in anemic growth. In non-fruiting leaves of control trees, higher auxins and salicylic acid, and lower jasmonic acid content were found compared to GA3 trees. In fruiting leaves, higher abscisic acid was found in control trees than GA3 trees, suggesting water deficient conditions. In February, non-fruiting leaves of control versus GA3, differentially expressed genes (DEGs) related to response to stress, defense response, and carbohydrate metabolic process were upregulated, and those with stomatal movement and gibberellic acid mediated signaling pathway were downregulated. DEGs encoding sucrose synthase (provide UDP-glucose for callose synthesis) and invertase (sucrose to hexose conversion) were upregulated in control compared to GA3 trees, indicating a higher capacity to import assimilates thus attracting water as well as callose accumulation. Furthermore, osmotic stress induced key markers including DEGs encoding lactate dehydrogenase and hexokinase, and the acyl-CoA-binding protein transcription factor family were upregulated in control compared to GA3 trees, with a concomitant of higher enzymatic activity of alcohol dehydrogenase in control trees. Altogether, control trees indicate a higher carbohydrate tradeoff on defenses against biotic (CLas), and abiotic (osmotic) stresses than on growth. GA3 improves vegetative growth as indicated by greater leaf weight and area, stem length, leaf relative water content thus improving photosynthetic activity as well as gas exchange potential in leaves. Thus facilitating, and better carbohydrate translocation within the tree body leading to better fruit retention on tree and productivity in HLB-affected sweet orange.

Profitability Analysis of Sweet Orange Production in Mamfe Municipality, Cameroon

This study aimed to investigate the profitability analysis of sweet orange production in Mamfe municipality, Cameroon. The study employed primary data collection through self-administered questionnaires to sweet orange farmers and a total of 200 samples were selected. The study used financial profitability analyses and percentage ranking to estimate the result. The gross return and net return for a hectare of the sweet orange orchard were 14155000 FCFA and 11759200 FCFA respectively for a 12 year sweet orange orchard. The NPV was estimated to be 4447824 FCFA per hectare of sweet orange orchard which indicates that sweet orange production fetches higher returns. The estimated BCR was 3.95 for a hectare of sweet orange orchard which shows that investment in sweet orange production is feasible for farmers. The production of sweet orange production was also found to be a profitable investment since the IRR was high (34.836%). The results also revealed that profits from sweet orange production have an impact on the livelihood of farmers. The result from the percentage ranking shows that the major constraints of sweet orange farmers are credit facilities, lack of agrochemicals, absence of extension services, high cost of farm inputs, high cost of labor, pests and diseases, and bushfires. The study concluded that sweet orange production was profitable and recommended that decision makers should promote sweet orange production via easy agricultural credits and others. This is a wise step towards improve well-being in Mamfe municipality in particular and Cameroon at large.

Valorization of Citrus peels: GC/MS-based metabolites profiling, multivariate analysis, and antiaging potential.

Aging and agro-waste are major challenges. Natural ingredients are preferred in skincare. This study intended to isolate the essential oils (EO) from the leftover peels obtained from three commonly edible Citrus species fruit peels, namely Citrus paradisi (grapefruit), Citrus sinensis (sweet orange), and Citrus deliciosa (mandarin). Gas chromatography/mass spectrometry analysis identified volatile constituents in EO and headspace aroma. Multivariate analysis distinguished between the three species. The antiaging effects of Citrus EO were assessed in vitro and in silico, studying volatile interactions with target enzymes. C. sinensis peels had the highest oil yield, rich in monoterpenes. C. paradisi and C. deliciosa contained sesquiterpenes. Limonene dominated the hydrodistilled EO: 94.50% in C. paradisi, 96.80% in C. sinensis, and 80.66% in C. deliciosa. Unsupervised multivariate analysis of Citrus species revealed that d-limonene, γ-terpinene, and β-pinene are the key phytochemical markers contributing to their diverse chemical composition. C. paradisi exhibited the highest enzyme inhibitory activity, with IC50 values of 12.82, 27.58, and 18.16 µg/mL for tyrosinase, elastase, and collagenase, respectively. In silico studies showed that the volatiles can inhibit the tested antiaging enzymes. According to these findings, the investigated agro-waste might slow aging in skin care.

Larvicidal Efficacy of Citrus sinensi (Sweet Orange) Peel Extract against Anopheles Mosquito Larva from Nagazi Adavi Local Government Area, Kogi State, Nigeria

Larvicidal Efficacy of Citrus sinensi (Sweet Orange) Peel Extract against Anopheles Mosquito Larva from Nagazi Adavi Local Government Area, Kogi State, Nigeria

HLB Progress and Yield Sustainability in Mature Sweet Orange Orchards Treated with Nutritional and Elicitor Products

Although the implementation of area-wide inoculum reduction and Asian citrus psyllid control are decisive in controlling Huanglongbing (HLB) epidemics, growers continue looking for enhanced nutritional and/or resistance inducer (ENRI) treatments to mitigate yield damage in HLB-affected trees. Therefore, an experiment was set up in an 8-year-old sweet orange orchard to evaluate the effects of the foliar application of nutrients, phosphite, and salicylate sprayed four to five times per year during flushing periods. The trial had eight treatments in four randomized blocks. HLB incidence and yield were assessed from December 2010 to January 2017. HLB-symptomatic trees with less than 5% HLB severity were selected from each plot in the first (Group 1), second (Group 2), and third years (Group 3) after the beginning of treatments to assess the frequency of trees with different HLB symptoms and micronutrient deficiencies, HLB severity, and fruit yield until January 2017. Twenty asymptomatic trees from each plot were also harvested for comparison each year. ENRI treatments did not reduce the progress of HLB incidence in the plots or the HLB severity progress or frequency of HLB symptoms in the selected trees. ENRI treatments did not improve the yield of symptomatic trees compared with asymptomatic trees. Hence, in a scenario without HLB-symptomatic tree removal in mature orchards, disease severity progress and yield reduction in HLB-affected trees remained regardless of ENRI treatment. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .

Selecting autotetraploids from a facultatively apomictic tree of the nonapomictic ‘Licheng’ sweet orange (Citrus sinensis) variety

Tetraploid plays major roles in the polyploid breeding and production of citrus plants. Autotetraploids of nonapomictic citrus varieties are desirable in citrus polyploid breeding due to their high frequencies of hybrid polyploid production, certain genotypes and some predictable phenotypes. However, it is difficult to obtain autotetraploids of nonapomictic citrus varieties. In the present study, the nonapomictic sweet orange variety ‘Licheng’, which is native to China, was used as the main material. A ‘Licheng’ tree, LCOYC-04, that produced polyembryonic seeds at a frequency of 34.96±2.88 % was selected. Plants that grew from self-pollinated polyembryonic seeds of LCOYC-04 were investigated by flow cytometry. Four tetraploids were selected from 550 plants and identified according to chromosome observation. Exonic single-nucleotide polymorphism (SNP) locus genotyping based on genome resequencing showed that 22.18 %-70.49 % of heterozygous loci in the genome of LCOYC-04 were homozygous in the genomes of plants grown from self-pollinated monoembryonic seeds. The proportions of homozygous loci were 2.07 %-2.45 % in the 4 selected tetraploids. These values were close to those in 7 asexual ‘Licheng’ relatives (1.97 %-2.71 %). Therefore, the 4 tetraploids were confirmed to be autotetraploids of LCOYC-04. Genome sequencing revealed a region of low sequencing depth (approximately 855 kb) on chromosome 4 of all ‘Licheng’ trees. The CitRWP gene, which is responsible for the occurrence of nucellar embryos in citrus plants, was located in the low sequencing depth region. It was confirmed by quantitative PCR that one of two allelic CitRWP gene was defective in genome of ‘Licheng’. The current study indicates that it is possible to induce nonapomictic citrus to mutate into facultatively apomictic citrus through chromosome segment deletion, and provides a reference for excavating autotetraploids which produce polyembryonic and monoembryonic seeds.

Fruit Quality Assessment of Novel Hybrid Pummelo × Sweet Orange and Its Molecular Characterization Using Acidity Specific Markers.

There is considerable diversity in newly developed pummelo × sweet orange citrus hybrids. Most hybrids showed lower peel thickness and high juice yield but there is a lack of information on fruit quality parameters and molecular characterization. Therefore, the aim of the current study is to determine the content of antioxidants and properties of the fresh juice of 24 new pummelo × sweet orange citrus hybrids (Citrus maxima [Burm. f.] Osbeck × Citrus sinensis [L.] Osbeck) and the parental genotypes along with molecular characteristics determined using acidity specific markers. The correlation and estimate of inheritance of the fruit juice properties: ascorbic acid, total phenol, total flavonoid, total antioxidant, total soluble solid and sugar contents, pH, titratable acidity, along with sensory evaluation was performed. Molecular characterization of these hybrids was carried out using de novo generated acidity specific simple sequence repeat (SSR) markers. The main constituents of the fruit juice of pummelo × sweet orange hybrids were observed in the range of w(ascorbic acid)=40.00-58.13 mg/100 g, total phenols expressed as gallic acid equivalents w(GAE)=40.67-107.33 mg/100 g, total antioxidants expressed as Trolox equivalents b(Trolox)=2.03-5.49 µmol/g, total flavonoids expressed as quercetin equivalents w(QE)=23.67-59.33 mg/100 g, along with other properties: total soluble solids=7.33-11.33 %, w(total sugar)=2.10-5.76 %, w(reducing sugar)=1.69-2.78 %, w(non-reducing sugar)=0.39-3.17 % and titratable acidity 1.00-2.11 %. The above parameters differed significantly in the fruit juice of the evaluated pummelo × sweet orange hybrids. Considering these parameters, the hybrids SCSH 17-9, SCSH 13-13, SCSH 11-15 and SCSH 3-15 had superior antioxidant properties in terms of these parameters. A higher heritability (≥80 %) was also observed for all juice properties. Molecular characterization of pummelo × sweet orange hybrids showed that >50 % of the hybrids were grouped with medium acidity parents. Both molecular and biochemical parameter-based clustering showed that interspecific hybrids exhibit transgressive segregation with increased antioxidants that help alleviate the health problems. These newly developed pummelo × sweet orange citrus hybrids are a valuable source of high-quality antioxidants for a healthy diet. The identification of trait markers that enable selection at the seedling stage is of great benefit to citrus breeders, as the characteristic features of a mature tree are not yet visible at the juvenile stage.

Genome-wide identification of the GRF family in sweet orange (Citrus sinensis) and functional analysis of the CsGRF04 in response to multiple abiotic stresses

BackgroundCitrus is one of the most valuable fruits worldwide and an economic pillar industry in southern China. Nevertheless, it frequently suffers from undesirable environmental stresses during the growth cycle, which severely restricts the growth, development and yield of citrus. In plants, the growth-regulating factor (GRF) family of transcription factors (TF) is extensively distributed and plays an vital part in plant growth and development, hormone response, as well as stress adaptation. However, the systematic identification and functional analysis of GRF TFs in citrus have not been reported.ResultsHere, a genome-wide identification of GRF TFs was performed in Citrus sinensis, 9 members of CsGRFs were systematically identified and discovered to be scattered throughout 5 chromosomes. Subsequently, physical and chemical properties, phylogenetic relationships, structural characteristics, gene duplication events, collinearity and cis-elements of promoter were elaborately analyzed. In particular, the expression patterns of the CsGRF genes in response to multiple phytohormone and abiotic stress treatments were investigated. Predicated on this result, CsGRF04, which exhibited the most differential expression pattern under multiple phytohormone and abiotic stress treatments was screened out. Virus-induced gene silencing (VIGS) technology was utilized to obtain gene silenced plants for CsGRF04 successfully. After the three stress treatments of high salinity, low temperature and drought, the CsGRF04-VIGS lines showed significantly reduced resistance to high salinity and low temperature stresses, but extremely increased resistance to drought stress.ConclusionsTaken together, our findings systematically analyzed the genomic characterization of GRF family in Citrus sinensis, and excavated a CsGRF04 with potential functions under multiple abiotic stresses. Our study lay a foundation for further study on the function of CsGRFs in abiotic stress and hormone signaling response.

Dissection of transcriptional events in graft incompatible reactions of "Bearss" lemon (Citrus limon) and "Valencia" sweet orange (C. sinensis) on a novel citrandarin (C. reticulata × Poncirus trifoliata) rootstock.

Citrus is commercially propagated via grafting, which ensures trees have consistent fruit traits combined with favorable traits from the rootstock such as soil adaptability, vigor, and resistance to soil pathogens. Graft incompatibility can occur when the scion and rootstock are not able to form a permanent, healthy union. Understanding and preventing graft incompatibility is of great importance in the breeding of new fruit cultivars and in the choice of scion and rootstock by growers. The rootstock US-1283, a citrandarin generated from a cross of "Ninkat" mandarin (Citrus reticulata) and "Gotha Road" #6 trifoliate orange (Poncirus trifoliata), was released after years of field evaluation because of its superior productivity and good fruit quality on "Hamlin" sweet orange (C. sinensis) under Florida's growing conditions. Subsequently, it was observed that trees of "Bearss" lemon (C. limon) and "Valencia" sweet orange (C. sinensis) grafted onto US-1283 exhibited unhealthy growth near the graft union. The incompatibility manifested as stem grooving and necrosis underneath the bark on the rootstock side of the graft. Another citrandarin rootstock, US-812 (C. reticulata "Sunki" × P. trifoliata "Benecke"), is fully graft compatible with the same scions. Transcriptome analysis was performed on the vascular tissues above and below the graft union of US-812 and US-1283 graft combinations with "Bearss" and "Valencia" to identify expression networks associated with incompatibility and help understand the processes and potential causes of incompatibility. Transcriptional reprogramming was stronger in the incompatible rootstock than in the grafted scions. Differentially expressed genes (DEGs) in US-1283, but not the scions, were associated with oxidative stress and plant defense, among others, similar to a pathogen-induced immune response localized to the rootstock; however, no pathogen infection was detected. Therefore, it is hypothesized that this response could have been triggered by signaling miscommunications between rootstock and scion either through (1) unknown molecules from the scion that were perceived as danger signals by the rootstock, (2) missing signals from the scion or missing receptors in the rootstock necessary for the formation of a healthy graft union, (3) the overall perception of the scion by the rootstock as non-self, or (4) a combination of the above.

Chemical Content and Pharmacology of Sweet Orange (Citrus sinensis) Fruit Peel: A Review

The sweet orange (Citrus sinensis) fruit peel is one of the often overlooked part of the sweet orange plant. However, recent research indicates that sweet orange peel possesses various bioactive properties and intriguing health benefits. The purpose of this article is to provide a comprehensive overview of the chemical compounds, pharmacological activities, and potential development of sweet orange peel, serving as an introduction to further research. Sweet orange peel contains a variety of chemical compounds, including essential oils, flavonoids, carotenoids, steroids, terpenoids, alkane groups, and ethyl esters. These chemical compositions confer antioxidant properties to sweet orange peel, which can protect the body from oxidative damage caused by free radicals. In vivo and in vitro studies have demonstrated that sweet orange peel extracts exhibit strong antioxidant activity and may aid in preventing degenerative diseases such as cancer. Additionally, sweet orange peel shows potential antimicrobial activity. Certain compounds in sweet orange peel have proven effective against various types of bacteria and pathogenic fungi.

Antimicrobial Activity of Pomegranate Peel and Its Applications on Food Preservation

Multiplex PCR is efficient in detection of Staphyloccocuus aureus and L.monocytogenes in food and may be used in tracing of toxins to promote food hygiene. Implications of contamination of processed meat to highlight food hygiene . The purpose of this study was to use Multiplex PCR for detecting listeria monocytogenes and Staphylococcus aureus in processed beef meat product . S.aureus 23S rRNA gene and L. monocytogenes 16SrRNA gene were used to detect Staphyloccocuus aureus and L.monocytogenes respectively in the examined beef meat product . A total of 40 random processed meat samples (10 each of minced meat, beef burger, beef sausage and beef kofta) were collected from different super markets in the study area (El-Menofia governorate). The peels of pomegranate fruits are the major by-products produced during food processing of pomegranate enriched in antioxidants and broad-spectrum antimicrobial agents and can prevent food deterioration even. In this study , the effect of The pomegranate peel extract give high microbial activity against Staphyloccocuus aureus and L.monocytogenes in minced meat. The in vitro antibacterial and antioxidant properties of hydromethanolic extract of peel from Citrus sinensis (Sweet orange) was investigated. In this study the antibacterial activity of Citrus sinensis peel extract against Stapyloccous aureus and listeria monocytogenes was reported ,Citrus sinensis peels had shown mild activity against the two microbes .

Efeitos da proteção solar e do manejo de água na fisiologia e produção de pomar de laranja ‘Pêra’ em clima subúmido

Abstract: The risks associated with climate events are the main factors responsible for sweet orange production losses in Brazil. For rainfed citrus cultivation, it is mainly due to soil water deficit, but also to citrus cultivation associated with extreme temperatures. The present study investigated the effects of water management in ‘Pera’ sweet orange orchards under sub-humid climate conditions and application of calcium carbonate-based sunscreen on the plant canopy, aiming to mitigate the effects of abiotic stresses on orchard physiology, production, and irrigation water use efficiency. The experimental design was in randomized blocks in a 3 x 2 factorial scheme. Treatments for water management factor were: full irrigation (100% ETc), irrigation with moderate deficit (65% ETc), and no irrigation; and for sunscreen protection: sunscreen use and no sunscreen. The factors have impacted gas exchange, fruit quality, and orchard yield. There was no isolated effect of soil water management on orchard productivity, but with sunscreen, citrus plants are more resilient based on gas exchange data, mitigating environmental effects (high temperatures and water deficit), resulting in improvements in fruit quality related to total fruit mass in plants grown without irrigation and with 12% increase in orchard productivity, regardless of soil water management. Productivity gains related to sunscreen indicate the need for the use of sunscreen protection regardless of soil water management in the region.

Population dynamics of citrus leaf miner and bark eating caterpillars on sweet orange (Citrus sinensis) using ICT-based pest surveillance

Population dynamics of citrus leaf miner and bark eating caterpillars on sweet orange (Citrus sinensis) using ICT-based pest surveillance

Optimization of in planta methodology for genome editing and transformation in Citrus.

Genetic transformation of many plant species relies on in vitro tissue culture-based approaches. This can be a labor-intensive process, requiring aseptic conditions and regenerating often recalcitrant species from tissue culture. Here, we have optimized an in planta transformation protocol to rapidly transform commercial citrus cultivars, bypassing the need for tissue culture. As a proof of concept, we used in planta transformation to introduce CRISPR/Cas9 constructs into Limoneira 8A Lisbon lemon and Pineapple sweet orange, cultivars that are challenging to transform with conventional techniques. Using our optimized protocol, the regeneration rate was significantly increased from 4.8% to over 95%, resulting in multiple gene-edited lines in lemon. We also successfully recovered gene-edited Pineapple sweet orange lines using this protocol; the transformation efficiency for these cultivars ranged between 0.63% and 4.17%. Remarkably, these lines were obtained within three months, making this in planta protocol a rapid methodology to obtain transformed citrus plants. This approach can rapidly and effectively introduce key genetic changes into a wide variety of citrus cultivars.

Standardisation of different levels and split application of nitrogen on growth and yield of sweet orange (Citrus sinensis (L.) OSBECK) CV. Phule Mosambi

Standardisation of different levels and split application of nitrogen on growth and yield of sweet orange (Citrus sinensis (L.) OSBECK) CV. Phule Mosambi

Chemometric discrimination of eight citrus plants utilizing chromatographic and spectroscopic techniques and insights into their biological potentials

Citrus sinensis balady orange, C. sinensis navel orange, C. paradisi, C. limon, C. sinensis bloody orange, C. sinensis sweet orange, C. aurantium var. amara and C. reticulata were successfully discriminated using chromatographic and spectroscopic techniques coupled with chemometrics. Ultraviolet spectroscopy (UV), and nuclear magnetic resonance spectroscopy (NMR) managed to discriminate the alcohol extract samples to six and five clusters respectively on exposing the obtained data to Principle component analysis (PCA). High performance liquid chromatography (HPLC) was utilized for differentiating the different samples based upon their rutin content where C. aurantium demonstrated the highest rutin content (0.795 mg/mL). LC-ESI-MS led to the identification of 35 compounds belonging mainly to flavonoids and limonoids. In vitro biological investigations including DDPH, ABTS, FRAP and enzyme inhibitory activities revealed the promising antioxidant, neuroprotective, anti-hyperglycaemic and skin-lightning potentials of citrus samples that were correlated with the total phenol and flavonoid contents. In silico ADME/TOPKAT reflected the acceptable pharmacokinetic, pharmacodynamic and toxicity properties of the identified secondary metabolites.

Effect of nutrients level on growth of sweet orange under Western Maharashtra conditions

Effect of nutrients level on growth of sweet orange under Western Maharashtra conditions

Quality properties of bread from blends of wheat flour and sweet orange seed protein concentrate

The study investigated the effect of substitution of wheat flour with sweet orange seed protein concentrate on the quality of bread. Protein concentrate, obtained from sweet orange (Citrus sinensis) seeds was used to substitute 5, 10, 15, 20 and 30% of wheat flour in breads. The flours were assessed for functional and pasting properties while the breads were evaluated for proximate composition, physical and sensory properties. Sweet orange seed protein concentrates and wheat flour had bulk densities of 0.45 g/cm3 and 0.72 g/cm3, respectively while those of the flour blends ranged from 0.61 - 0.70 g/cm3. Wheat flour had lower contents of moisture, crude fiber, ash, protein, and fat than the protein concentrate, which had lower carbohydrate content. Sweet orange seed protein concentrate had highest foaming capacity, water and oil absorption capacities but lowest least gelation concentration among all the flours. The peak viscosities of protein concentrate and wheat flour were 886.21 RVU and 675.20 RVU, respectively. The peak, trough, breakdown, final and setback viscosities of the flour blends decreased while peak time and pasting temperature increased with increase in the substitution of wheat flour with protein concentrate. In length, loaf weight, height, oven spring, loaf volume, specific volume and weight loss, the 100% wheat flour breads had 12.03 cm, 172.60 g, 5.35 cm, 0.62 cm, 471.50 cm3, 2.73 cm3/g and 10.42%, respectively while breads containing 5% sweet orange seed protein concentrate had 12.02 cm, 171.40 g, 4.60 cm, 0.61 cm, 350.50 cm3, 2.04 cm3/g and 9.28 %, respectively. The proximate composition of the breads containing 5 and 10% sweet orange seed protein concentrate were improved over that of wheat flour bread. The sensory attributes of the breads decreased with increased level of sweet orange seed protein concentrate in the breads. However, the breads containing 5 and 10% sweet orange seed protein concentrate were not significantly (p>0.05) different from the 100% wheat bread in colour. Thus, the incorporation of up to 10% sweet orange seed protein concentrate in wheat flour improved the functional properties of the flour blends and the qualities of the bread. Adoption of this approach will address malnutrition, wastages and environmental pollution (caused by the discard of orange seeds).

Efficacy of bio-based extracts on shelf life and quality of orange (citrus sinensis) fruits during storage in Makurdi, Nigeria

Experiment was conducted at the Biological Sciences Laboratory of Benue State University, Makurdi, Nigeria to determine the efficacy of bio-based extracts (Aloe vera and Gum arabic) on shelf-life and quality of sweet orange. Healthy orange fruits of two varieties (Valencia and Washington) used in the trial were picked at harvest maturity. The experimental design was a 2 x 4 factorial combination, fitted in a completely randomized design and replicated three times. The treatments consisted of two varieties of sweet orange and four extracts regimes (Aloe vera, Gum arabic, Aloe vera+Gum arabic and Control). The orange fruits were treated by dipping in extracts the various treatments until they were completely coated while the control fruits were not treated. The treated fruits and control were stored at ambient conditions of light and temperature for four weeks. Percentage weight loss, total soluble solids, fruit firmness, Vitamin C/Ascorbic acid content, pH, titratable acidity, decay percentage (DP %), marketability and shelf life of the fruits were recorded. The data were subjected to Analysis of Variance (ANOVA) using GENSTAT statistical package, and mean separation was done using Fisher’s Least Significant Difference (F-LSD) at 5% level of probability. Percent weight loss, fruit firmness, % decay and fruit marketability were significantly higher (P≤0.05) in Valencia compared with Washington. Fruits treated with Gum Arabic had significantly lower % weight loss and % decay compared with the control (P≤0.05). Fruit firmness was significantly higher (P≤0.05) in fruits treated with Gum Arabic + Aloe Vera while marketability was significantly higher in Aloe Vera treated fruits. All the treated fruits had significantly higher (P≤0.05) shelf life compared with the control. With respect to nutritional values, TSS was significantly higher (P≤0.05) in Valencia compared with Washington while Vitamin C and pH were significantly higher (P≤0.05) in Washington compared with Valencia. The TSS was significantly higher (P≤0.05) in Aloe Vera and Aloe Vera + Gum Arabic treated fruits compared with the control. The Vitamin C content of fruits treated with Gum Arabic was significantly (P≤0.05) higher followed by Aloe Vera + Gum Arabic compared with the control. All the treated fruits had significantly higher pH while TA was significantly lower (P≤0.05) compared with the control. Percent weight loss was positively and significantly correlated with % decay while marketability, shelf life, TSS, and TA were negatively and significantly correlated. The botanicals tested are environmentally friendly, cost-effective, easy to produce and also safe for consumers. The bio-based extracts of Aloe vera and Gum Arabic are recommended in the storage of flesh sweet orange fruits.

An Inception of Value Chain Development of Sweet Orange; Kinesis to Food Security in the Developing Countries Scenario

Sweet orange is one of the major citrus fruits of Nepal which is widely cultivated in mid-hills. This paper assesses the value chain of sweet oranges cultivated in the Ramechhap district of Nepal, considering its economic significance for farmers. The study adopts a qualitative research approach, utilizing key informant interviews and focus group discussions with various stakeholders. Participants were selected based on a list of producers collected from the Prime-Minister Agricultural Modernization Project (PMAMP) Ramechhap district, and the snowball method was employed to identify other actors. This study revealed that the value chain of sweet oranges in the Ramechhap district involves growers, vendors, wholesalers, retailers, and consumers as the main actors, while federal, provincial, and local agricultural service centres serve as enablers. Additionally, findings show vendors play a dominant role, in determining the per unit price and pressuring farmers to sell immediately after harvest due to limited storage capacity. Vendors are enjoying increased profit margins because they have greater bargaining power over farmers, who have inadequate storage facilities. The study suggests areas for improvement: using quality seedlings, managing nutrients effectively, and employing proper storage techniques like cold stores to prolong shelf-life and enhance quality, taste, and colour. Enhancing productivity via trifoliate rootstock, optimizing fruit quality, and extending shelf-life through improved storage facilities can substantially boost revenue for producers. Understanding the entire value chain provides insights into enhancing the overall performance of value chain actors. Further studies can explore additional dimensions of the chain in more depth.