Papaya Varieties Research Articles

Diversity Profiling of Seed Associated Endophytic Microbiome in Important Species of Caricaceae Family

Background: Plant associated endophytic microbes play an important role in plant’s growth and development. After seed germination, the seed associated endophytes rapidly colonize the seedlings and help in their growth and protection against pathogens. This study was aimed to understand the diversity in the endophytic microbial population associated with the seeds of papaya (Carica papaya) and its wild relatives from Vasconcellea genus (family: Caricaceae). The species of Vasconcellea genus are widely used to introgress virus resistance in cultivated varieties of papaya. Hence, the diversity of seed associated endophytic microbes and their gene functional analysis was carried out through next generation sequencing of the microbial 16S rRNA and ITS sequences. Results: The 16S rRNA amplicon analysis revealed that the number of operational taxonomic units (OTUs) was higher for the endophytic bacteria, ranging between 144–204 when compared to 41–69 OTUs for the endophytic fungi. The bacterial phylum Proteobacteria was the most abundant seed associated phylum, with 64.7–72.8% abundance, across all four species of Caricaceae family, followed by Firmicutes (13.6–26.1%), Patescibacteria (1.1–2%) and Actinobacteria (0.7–2.7%). With respect to the diversity of bacteria by abundance indices, Vasconcellea goudotiana had the highest OTUs of 204, followed by 177 in V. cauliflora, 156 in V. cundinamarcensis, and 144 in C. papaya. The alpha diversity indices and functional analysis revealed the differences in the OTUs and the functional annotations among the above four plant species. The fungal OTUs were in the range of 41–69; however, only a small fraction of them could be taxonomically classified. Conclusion: Our microbiome studies reveal the differences in the seed associated endophytic microbial community across the four plant species of Caricaceae family. This study also unravels the composition of endophytic microbial population associated with the seeds of different plant species of Caricaceae family and their gene functions. It also provides an insight into both culturable and nonculturable endophytic microbes. Further this study reveals that domestication of Carica papaya might have resulted into reduced microbial diversity when compared to their wild relatives from Vasconcellea genus.

Effect of High Hydrostatic Pressure on the Extractability and Bioaccessibility of Carotenoids and Their Esters from Papaya (Carica papaya L.) and Its Impact on Tissue Microstructure.

High hydrostatic pressure (HHP) is a non-thermal technology widely used in the industry to extend food shelf-life and it has been proven to enhance the extractability of secondary metabolites, such as carotenoids, in plant foods. In this study, fresh-cut papaya pulp of varieties (Sweet Mary, Alicia and Eksotika) from the Canary Islands (Spain) were submitted to the HHP process (pressure: 100, 350 and 600 MPa; time: come-up time (CUT) and 5 min) to evaluate, for the first time, individual carotenoid and carotenoid ester extractability and to assess their bioaccessibility using an in vitro simulated gastrointestinal digestion assay, following the standardized INFOGEST® methodology. In addition, changes in papaya pulp microstructure after HHP treatments and during the different phases of the in vitro digestion were evaluated with optical light microscopy. HPLC-DAD (LC-MS/MS (APCI+)) analyses revealed that HHP treatments increased the carotenoid content, obtaining the highest extractability in pulp of the Sweet Mary papaya variety treated at 350 MPa during 5 min (4469 ± 124 μg/100 g fresh weight) which was an increase of 269% in respect to the HHP-untreated control sample. The highest carotenoid extraction value within each papaya variety among all HHP treatments was observed for (all-E)-lycopene, in a range of 98–1302 μg/100 g fresh weight (23–344%). Light micrographs of HHP-treated pulps showed many microstructural changes associated to carotenoid release related to the observed increase in their content. Carotenoids and carotenoid esters of papaya pulp submitted to in vitro digestion showed great stability; however, their bioaccessibility was very low due to the low content of fatty acids in papaya pulp necessary for the micellarization process. Further studies will be required to improve papaya carotenoid and carotenoid ester bioaccessibility.

Papaya (Carica papaya L.) Flavour Profiling.

A major challenge to the papaya industry is inconsistency in fruit quality and, in particular, flavour, which is a complex trait that comprises taste perception in the mouth (sweetness, acidity, or bitterness) and aroma produced by several volatile compounds. Current commercial varieties vary greatly in their taste, likely due to historical prioritised selection for fruit appearance as well as large environmental effects. Therefore, it is important to better understand the genetic and biochemical mechanisms and biosynthesis pathways underpinning preferable flavour in order to select and breed for better tasting new commercial papaya varieties. As an initial step, objectively measurable standards of the compound profiles that provide papaya’s taste and aroma, together with ‘mouth feel’, are required. This review presents an overview of the approaches to characterise the flavour profiles of papaya through sugar component determination, volatile compound detection, sensory panel testing, as well as genomics-based studies to identify the papaya flavour.

Performance of papaya variety ‘Surya’ under fertigation and foliar nutrition

Effects of fertigation and foliar nutrition with micronutrients on papaya flowering, yield and fruit quality parameters were studied during the period 2018 – 2020 at Instructional Farm, College of Agriculture, Vellayani, Thiruvananthapuram, Kerala, India. A field experiment consists of 14 treatments replicated thrice was laid out based on randomized block design. A combination of four fertigation doses of 75 %, 100 %, 125 % and 150 % Recommended Dose of Fertilizers (RDF) of N (304.89, 406.52, 508.15 and 609.78 gm urea plant-1 year-1 respectively based on soil test data in 76 fertigation) and K (426.25, 568.33, 710.42 and 852.50 gm muriate of potash plant?¹ year?¹ respectively based on soil test data in 76 fertigation) and three foliar sprays (1.0 % 19:19:19 at bimonthly interval starting from 4 MAP (Month After Planting) to 16 MAP, 0.5% ZnSO4 + 0.3% borax at 4th, 8th, 12th and 16th MAP and water spray at bimonthly interval starting from 4 MAP to 16 MAP) where compared with soil application of recommended dose of NPK (187:170:341 g NPK plant-1 year-1 based on soil test data) (control 1) and 187:170:341 g NPK plant-1 year-1 based on soil test data as organic manures as combination of FYM (Farm Yard Manure), poultry manure and vermicompost in the ratio of 2:1:1 (control 2). Application of 100 % recommended dose of N and K through fertigation at weekly interval from one MAP to 20 MAP and foliar sprays of 0.5 % ZnSO4 and 0.3 % borax at 4th, 8th, 12th and 16th MAP (T5) initiated earliness in flowering (142.67 days) and harvest (275.00 days). However, plants receiving 100 % recommended dose of N and K through fertigation at weekly interval from one MAP to 20 MAP with foliar sprays of 1% 19:19:19 at bimonthly interval starting from 4 MAP to 16 MAP (T4) significantly improved the fruit weight, number of fruits per plant and total yield per plant in papaya variety ‘Surya’ and it was on par with T5. Fruit quality parameters namely TSS (Total Soluble Solids), ascorbic acid and total sugars were found significantly highest in T5 and lowest titratable acidity was also recorded in T5. Hence, treatment T5 which is found superior in initiating early harvest, with higher yield and good quality characters in papaya variety ‘Surya’ can be recommended to farmers.

Optimization of Annealing Cycle and Temperature SNAP T12 Primer Distinguishing Markers for Male, Female and Hermaphrodite Plants in Papaya (Carica papaya L)

Papaya has three types of efflorescense which are male flowers, female flowers, hermaphrodite. That was difficult to determine in advance for the type of flower that appear. The molecular technology approach is an effort to quickly predict the types of flowers that will appear. SNAP primers were designed based on SNP on genomic sequences of male papaya and hermaphrodite DNA. This research aimed to found the specific cycle and annealing temperature for PCR. The research was conducted at the in Indonesia Tropical Fruit Research Institute from January to March 2020. The SNAP primer used was T12, The plants used were papaya varieties of Pomegranate and local cultivar from male and hermaphrodite aged 8 months trees. The results showed that an annealing temperature of 59°C with a cycle of 28 times as effective in producing male DNA amplification on SNAP T2 reverse (R) primers and hermaphrodite DNA amplification plants appeared on alternate SNAP T12 primers (A) with a product size is 430 bp, while female plants did not occur. Amplification according to the SNAPT12 primer.

Carotenoid and Carotenoid Ester Profile and Their Deposition in Plastids in Fruits of New Papaya (Carica papaya L.) Varieties from the Canary Islands.

The carotenoid profile of non-saponified and saponified extracts of different tissues (pulp and peel) of fruits of three new papaya varieties, Sweet Mary, Alicia, and Eksotika, was characterized for the first time, and almost all carotenoid compounds were quantified. Carotenoids and carotenoid esters were analyzed and characterized using HPLC-photo diode array (PDA-MS with atmospheric pressure chemical ionization with positive ion mode (APCI+) with a C30 reversed-phase column. The carotenoid deposition in collenchyma and chlorenchyma cells of papaya pulp and peel tissues was assessed by optical microscopy, confocal laser scanning microscopy, and transmission electron microscopy. The most abundant carotenoids in the fruit of the three papaya varieties (pulp and peel) were (all-E)-lycopene (230.0–421.2 µg/100 g fresh weight), (all-E)-β-carotene (120.3–233.2 µg/100 g fresh weight), and (all-E)-β-cryptoxanthin laurate (74.4–223.2 µg/100 g fresh weight. Moreover, high concentrations of (all-E)-lutein (922.5–1381.1 µg/100 g fresh weight) and its esters, such as (all-E)-lutein-3-O-myristate and (all-E)-lutein dimyristate, were found in peel extracts. The optical microscopy study of papaya pulps showed that carotenoid deposition in all papaya varieties, including Maradol, was mainly localized close to the cell walls, showing the presence of some crystalloids and round-shaped structures, with different sizes and distribution due to the different carotenoid content among varieties. No crystalloids or globular depositions were found in any of the peel sections, and no remarkable differences were found in the papaya peel microstructure of the different papaya varieties.

The papaya selection based on fruit characters: a way to assembly new preferred variety

The recent program for assembly new papaya variety was aimed to improve its quality, which based on consumer preference on papaya fruit characters namely size (small to medium), flesh thickness, flesh color (reddish, orange and chewy), and the taste (sweet). To get that kind of papaya variety, a plant breeding program could be applied to assembly. Indonesian Tropical Fruit Research Institute (ITFRI) had conducted several papaya hybridizations in order to obtain a wide genetic variability. The study was carried out in Sumani Experimental Filed of ITFRI, Solok Regency, West Sumatra, and performed to select high-quality papaya hybrids based on the fruit characters. The tested genotypes were selected based on its heritability index on fruit size (length, diameter, and weight), flesh thickness and total dissolved solids (TSS). As the results, six papaya varieties were selected based on fruit character, which mirroring best quality of papaya fruit.

The study of distribution of chicken manure fertilizer for papaya growth and production beneath unproductive palm oil

The research was conducted in Naga Sari village, Muaro Jambi regency, from February 2020 to June 2020. The design applied was a group-randomized design with 2 treatment factors. The first factor was the California variety (V1) and ruby rise red variety (V2). The second factor was chicken manure distribution: without fertilizer distribution (P0), 50 g of (P1), 100 of (P2), 150 of (P3), and 200 of (P4). The result of this research showed that the distribution of 150 g has a real impact on the plant’s height and stem diameter, and the number of fruits on 5 Months After Cultivating to 6 Months After Cultivating. Variety treatment doesn’t have a real impact on the papaya observation parameter. The interaction among the varieties with a dose of chicken manure has a real impact on plant height, stem diameter, and a number of the leaf. Qualitative data from papaya varieties showed fruit color and taste experiment gets the real impact. The impact of papaya plants and chicken manure showed a good growth tendency on palm oil cultivated with ruby rise red papaya as the side plant. The organoleptic test shows that the variety of Ruby papaya is preferred.

Potency of Papaya Seed Powder (Carica papaya L.) as Chicken Meat and Shrimp Preservative

Chicken meat and shrimp are perishable food materials. Giving natural preservatives is one way to extend the storage time of food. This study aimed to know the potential of papaya seed powder varieties of ‘Bangkok’ and ‘California’ as preservatives. The sample consisted of two varieties of papaya seed powder with concentrations of 2,4,6 and 8 g. Storage time for chicken meat and shrimp was the third days. Parameters measured were total bacterial colonies, pH va-lues, and organoleptic characteristics (color, aroma and texture) of fresh chicken meat and shrimp. The result showed papaya seed pow-der influences the quality of chicken meat and shrimp. fresh chicken meat and shrimp with papaya seed powder varieties ‘Bangkok’ and ‘California’ had a lower total bacterial colony as much as 9 x 105 until 1x106 compared to control which were 4.2 x 107 - 1.87 x 107. Organoleptic result of chicken meat and shrimp with the treatment of papaya seed powder and stored for three days continue to decrease in term of color, aroma and texture. In chicken meat, the decrease in bacterial growth was still within the limits of microorganism con-tamination quality in animal-based food. However, the same con-centrations of papaya seed powder in the shrimp have not been able to reduce bacterial growth until the limit permitted by SNI.

Variability of physio-chemical, anti-oxidant, and sensorial quality of newly released papaya varieties in Ethiopia

A study was carried out to investigate the physic-chemical, proximate, antioxidant, and sensorial qualities of the released papaya varieties namely, KK-103, MK-121, and CMF-078 which are widely grown in Ethiopia.

Studies on Effect of Different Packaging Materials on Shelf-Life of Blended Guava-Papaya Fruit Leather

Aims: To study the effect different packaging materials on shelf-life and quality of blended fruit leather.
 Place of Study: The present investigation was carried out at the Department of Post-Harvest Technology and Agri. Engineering, Indian Institute of Horticultural Research (IIHR), Bengaluru.
 Methodology: Guava variety ‘Allahabad Safeda’ and papaya variety ‘Taiwan Red Lady’ fruit leathers were prepared by blending their pulp at different ratios of 100:0, 80:20, 60:40, 50:50, 40:60, 20:80 and 0:100 respectively. Citric acid at 0.3% and KMS (Potassium meta-bisulphite) at 600 ppm was added to the blended pulp and TSS was adjusted to 20°B. The pulp according to treatments were then dried in a cabinet drier at 55 to 60°C till the desired moisture content (approx. 15%) was achieved.
 Results: Blended guava-papaya (40:60) leather was found best among the treatments in terms of better nutritional and sensory characteristics at initial and also during the subsequent storage periods. The prepared fruit leathers that were packed in biaxially oriented polypropylene showed better results with better nutrient retention (ascorbic acid 90.1 mg/100 g and carotenoids 947.2 µg/100 g) and higher organoleptic score (70.03 overall acceptability out of 100) to those packed in punnets (ascorbic acid 73.2 mg/100 g, and carotenoids 893.0 µg/100 g) during the storage period of 4 months. The microbial examination also revealed that all the samples were found to be safe from the consumption point of view till the end of four months of storage. 
 Conclusion: The blended fruit leather can be a good source of various heath promoting phytochemical nutrients with a unique taste and acceptability having a storage stability for safe consumption till 4 months.

Evaluation of different papaya varieties for yield and quality parameters under Rayalaseema zone of Andhra Pradesh, India

Papaya (Carica papaya L.) is one of the most important fruits of tropical and subtropical regions of the world. It is believed to be native of Tropical America; probably Southern Mexico from where it spread to most of the Caribbean and Asian countries during the16th century. India stands first in the production of papaya in the world followed by Nigeria, Indonesia, Mexico, Ethiopia and others. The fruit has high nutritive and medicinal value especially vitamin A (2020 IU/l00g). It also possesses vitamin B, folate and pantothenic acid besides minerals like potassium and magnesium. Five papaya varieties were evaluated for yield and quality parameters under rayalseema dry zone of Andhra Pradesh. The highest yield per plant (45.57 kg) was recorded in TFCP-2 while highest estimated yield per hectare (121.62t/ha) was recorded in the variety Red Lady. Maximum fruit length (21.80 cm), maximum level of total soluble solids (14.88 0brix) was found in the variety TFCP-4. However, Highest pulp thickness (3.96 cm) was recorded in the variety Red Lady. Among five papaya varieties Red lady was found to be superior in terms of yield and quality parameters.

Foliar Traits in Papaya Plants Intercropped in Coconut

The present study compared the shade adapting traits among the two gynodioecious papaya varieties Arka Surya and Arka Prabhath intercropped in coconut garden. Morphological traits such as internodal length, leaf traits (area, colour attributes, fresh and dry weight), fruit number, fruit weight and yield were analysed. Correlations and step-wise regression equations were used to infer the relationship among the traits and fruit yield. Larger leaf area, greater internodal length, high leaf fresh weight, high leaf dry weight, small fruits and low fruit yield were observed in Arka Surya. Fresh weight, dry weight and lightness of leaf together showed significant regression (R2 = 0.528) with annual fruit yield per plant. Arka Prabhath performed better than Arka Surya under coconut canopy with optimal fruit size and yield.

Differential Influence of Growth Regulators during Somatic Embryogenesis of Gynodioecious Papaya Varieties‘CO.7’ and ‘Red Lady

The study involved two auxins viz., 2,4-D (2,4-Diclorophenoxyacetic acid) and picloram at three different concentrations (1,2, 3 mg/L) in full strength MS media to study their comparative influence on induction of somatic embryogenesis from immature zygotic embryos of two gynodioecious varieties of papaya ‘CO.7’ and ‘Red Lady’. In papaya cultivar ‘CO.7’, 2,4-D at 2 mg/L gave the highest callus induction frequency of 90.93%, whereas comparatively higher concentration of 3 mg/L 2,4-D was found suitable for ‘Red Lady’ (87.26%). Although there was profuse callus formation, 2 mg/L 2,4-D recorded comparatively higher frequency of embryogenic calli in ‘Red Lady’ (51.67%) when compared to ‘CO.7’ (30.00%). Somatic embryo maturation was achieved upon transfer of embryogenic calli exhibiting globular stage embryos on to maturation medium (MS medium + ABA (Abscisic acid) and BAP (Benzyl amino purine) in different concentrations + glutamine 400 mg/L). In the maturation medium, the combination of 1.5 mg/L ABA and 0.4 mg/L BAP registered better conversion of the globular embryo to cotyledonary embryos than other levels. The frequency of somatic embryo germination was higher in ‘Red Lady’ (50.00%) as compared to ‘CO.7’ (31.67%) on half-strength MS medium devoid of growth regulators.

Correlation between Off-flavor and Morphology of Papaya (Carica papaya L.) Fruits

Aims: To investigate the correlation between fruit morphology and off-flavor characteristics which are naturally present in papaya.
 Place and Duration of Study: Department of Food Science and Technology (Sensory Laboratory and Food Analysis Services Laboratory), Centre for Tropical Horticulture Study (Chemistry Laboratory) and Indonesian Centre for Rice Research of Indonesian Agriculture Ministry (Flavor Laboratory), between December 2014 and September 2015.
 Methodology: Morphology descriptions of 6 papaya varieties, i.e. “Carisya”, “Callina”, “Sukma”, “Merah Delima”, “Burung” and “Bangkok”; off-flavor description using Quantitative Descriptive Analysis; semi-quantification of volatile compounds by using Headspace Solid-Phase Micro-Extraction and Gas Chromatography-Mass Spectrometry have been conducted.
 Results: The stinky-sour odor had positive correlation with the presence of butanoic acid (r=0.879) and octanoic acid (r=0.876). The stinky-sour odor had negative correlation with the weight (r= -0.836), length (r= -0.873), flesh thickness (r= -0.887), and ripe peel color (r= -0.838) in accordance to the octanoic acid content which showed negative correlation to fruit weight (r= -0.871), length (r= -0.830) and ripe peel color (r= -0.911). The stinky-sour odor as well as the concentration of butanoic and octanoic acid were most dominant in “Burung” and “Carisya” papayas. “Callina” and “Sukma” papayas had the weakest off- flavor intensity.
 Conclusion: The off-flavor perception of papaya was dominated by stinky-sour odor. The presence of octanoic acid might deliver synergism impact to butanoic acid in giving the perception of stinky-sour odor. High concentration of octanoic acid and strong intensity of stinky-sour odor were closely related to the small type of fruit weight (650 g or less), short size fruit (16.5 cm or less), thin flesh (less than 3 cm), and papaya varieties with orangish ripe peel color. These phenomena can be utilized in selection process in the field selection criteria to breed favorable papaya varieties.

ADAPTASI TIGA VARIETAS PEPAYA (MERAH DELIMA, JUPE, MADU) DI LAHAN KERING DATARAN RENDAH

Papaya fruit (Carica papaya L.) is classified as having high economic value and is being developed by many farmer. A common problem is the papaya variety that farmer \s develop usually from careless seeds, so the production and quality are low. The aim of this research is to introduce superior papaya and have good quality. Three varieties papaya are used in this study, namely: Merah Delima, Jupe, and Madu.The research location is located in the dry land of Banturung, Palangka Raya City. The result that the land suitability class of the study site included S3wa,on, which is Marginal Suitability with the heaviest inhibiting factors of water availability and oxygen availability. On Growth parameters, then Merah Delima has the largest stem circumference of 10,1 cm althought it is not significantly different from other varieties 8,8 cm. While the plant height is the best Merah Delima papaya and signficantly different from Madu. Interms of Productioan Jupe has a number of Fruits (38 fruits/tree) that are significantly different from Madu, and the weight of fruit (1,2 kg/fruit) is significantly different from Merah Delima., and fruit weight per tree 34,1 kg is significantly different from the other two varieties. Base on the sweetness level, the sweetest Merah Delima reaches 9,1 oBrix significantly different from Jupe (6,9 oBrix) and Madu (6,6 oBrix). Parameters of growth, productionand quality of papaya can still be improved by improving the management of inhibiting factors.

Physicochemical and Sensorial Analysis of Papaya Varieties in Ethiopia

A study was carried out on three papaya varieties namely, KK-103, MK-121 and CMF-078 for their physico-chemical, nutritional composition and sensory evaluation grown at Ethiopia. The results showed that maximum fruit weight was observed in MK-121 and lowest in CMF-078. It was also found that the TSS, citric acid, total carotenoid and vitamin C were 10.287-12.620 (brix), 1.455- 1.978 (g/l), 13.670-18.912 (µg/g) and 30.854-36.507 (mg/100g) respectively. Proximate analysis of the pulp showed that it contained crude protein (0.200- 0.907%), energy (32.744-44.280 kcal/g), crude fat (0.215-0.293%) and fibre (0.732-0.995%). All these results indicate that significantly difference between the papaya varieties. This difference may be come from genetically difference between the varieties. The results showed that papaya fruits had high moisture content (>85.5%), low acidity (>5.3 P^H), low crude fat and crude fibre moderate ascorbic acid contents. The sensory evaluation statistical results were showed in case of color, flavor, sourness and sweetness MK-121 Varity was showed significance difference and a higher value than the other two of varieties of papaya whereas except sweetness. The color, flavor and sourness of the two varieties (CMF-078 and kk-103) were showed the same in statistics value. Accordingly, the panelist result in overall acceptability of the sensory CMF-078 variety was showed high acceptability than the others two varieties. Additionally, the statistical result showed significantly different at P<0.05.

Effect of Calcium Nitrate and Potassium Nitrate Priming on Seed Germination and Seedling Vigour of Papaya (Carica papaya L.)

The effect of seed priming with calcium nitrate Ca (NO3)2 and potassium nitrate (KNO3) on germination and seedling vigour were studied in papaya varieties. Open pollinated local (gauty) papaya seeds were soaked in Ca (NO3)2 and KNO3 solutions (10000 ppm, 15000 ppm and 20000 ppm) up to 24 hours and germination percentage and seedling characteristics were recorded. The least number of days taken for seed germination (4.33 days), the highest germination percentage (82.56 % ), the highest shoot length (14.31 cm) the highest fresh biomass (1.36 g) and dry biomass (0.174 g) were recorded in 10000 ppm Ca(NO3)2 treatment. Further, seeds of papaya varieties viz., Arka Surya, Arka Prabhat and Madhu bindhu were treated with 5000 ppm, 10000 ppm and 15000 ppm Ca (NO3)2 and observed that Arka Prabhat seeds treated with 10000 ppm Ca (NO3)2 hadtaken the least number of days for germination (4.75 days) and also the highest shoot length (25.2 cm). The results of the experiment proved the significant effect of calcium ions over potassium ions on papaya seed germination and seedling vigour.

Effect of Calcium Nitrate and Potassium Nitrate Priming on Seed Germination and Seedling Vigour of Papaya (Carica papaya L.)

The effect of seed priming with calcium nitrate Ca (NO3)2 and potassium nitrate (KNO3) on germination and seedling vigour were studied in papaya varieties. Open pollinated local (gauty) papaya seeds were soaked in Ca (NO3)2 and KNO3 solutions (10000 ppm, 15000 ppm and 20000 ppm) up to 24 hours and germination percentage and seedling characteristics were recorded. The least number of days taken for seed germination (4.33 days), the highest germination percentage (82.56 % ), the highest shoot length (14.31 cm) the highest fresh biomass (1.36 g) and dry biomass (0.174 g) were recorded in 10000 ppm Ca(NO3)2 treatment. Further, seeds of papaya varieties viz., Arka Surya, Arka Prabhat and Madhu bindhu were treated with 5000 ppm, 10000 ppm and 15000 ppm Ca (NO3)2 and observed that Arka Prabhat seeds treated with 10000 ppm Ca (NO3)2 hadtaken the least number of days for germination (4.75 days) and also the highest shoot length (25.2 cm). The results of the experiment proved the significant effect of calcium ions over potassium ions on papaya seed germination and seedling vigour.

Field performance of hermaphrodite papaya plants obtained through molecular selection and micropropagation

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