Dragon Fruit ( Hylocereus undatus ) Pollination in New Zealand: A Preliminary Report on Flower Visitors, Natural Pollen Deposition, and Artificial Pollination

Pollen viabilities and stigma receptivities of 19 accessions in Viola tricolor were assayed by in vitro pollen germination and benzidine-H 2 O 2 method in this paper respectively. The seed set through hand-pollinate selfing was also investigated. The results showed that the pollen germination percent of V. tricolor reach peak at 8 h after in vitro germination and at that time pollen viabilities among 19 accessions were significantly different. The pollen viability of ‘08-NL-H5’ is the highest with 65.14% germination and that of ‘EP-1’ is lowest with 19.32% germination. The stigma receptivity of V. tricolor was up to best on flower opening day and declined to nearly zero on fifth day after flowering. The variation of stigma receptivities among 19 accessions are great, in which the stigma receptivity of ‘Yellow-1’ is strongest and that of ‘Yellow-2’ is weakest. The variation of seed sets among 19 accessions are also divesity by manual selfing pollination. The correlation between the pollen viability and the stigma receptivity is significantly high, but the correlation between seed set and pollen viability, and seed set and stigma receptivity in V. tricolor are low, which implies that the compatibility between pollen and stigma of V. tricolor maybe lies in important role during pollination and fertilization.

Plants in the Gesneriaceae family are appreciated for their decorative leaves and flowers, ease of cultivation, and shade tolerance. Sexual hybridisation has long been carried out for producing novel hybrids. However, scientific knowledge is lacking on the correct timing of pollination in this family. This study was conducted to elucidate the optimal timing for pollination by screening pollen viability and stigma receptivity throughout the flowering period in eight gesneriad taxa. Pollen viability was evaluated by the in vitro germination test and stigma receptivity was based on stigma morphology and pistil length. The flowering duration varied from 10 days in Alsobia to 18 days in Streptocarpus. While the pollens of Episcia, Kohleria, Saintpaulia, Sinningia, and Smithiantha had totally lost viability 2–5 days before the flowers withered, a slightly contrasting situation was observed in the cases of Alsobia, Deinostigma, and Streptocarpus, where a small portion of pollen grains remained viable towards the end of the flowering period. The highest pollen germination rate was recorded from 1 day in Alsobia, Episcia, and Kohleria, to 9 days in Deinostigma. The reduction in pollen germination was rapid in Alsobia, Saintpaulia, and Smithiantha, and moderate in the remaining taxa. The greatest pollen tube growth occurred at 1–3 days after flower opening and decreased rapidly in all the taxa tested. The longest pistil of 2.03–3.50 cm was observed at 3–8 days of anthesis depending on the plant tested. The findings in this study suggest that higher pollination success may be achieved using pollen grains of newly opened flowers and stigmas of mature flowers in this family.

Dragon fruit (Hylocereus undatus) is a tropical and subtropical fruit that undergoes multiple ripening cycles throughout the year. Accurate monitoring of the flower and fruit quantities at various stages is crucial for growers to estimate yields, plan orders, and implement effective management strategies. However, traditional manual counting methods are labor-intensive and inefficient. Deep learning techniques have proven effective for object recognition tasks but limited research has been conducted on dragon fruit due to its unique stem morphology and the coexistence of flowers and fruits. Additionally, the challenge lies in developing a lightweight recognition and tracking model that can be seamlessly integrated into mobile platforms, enabling on-site quantity counting. In this study, a video stream inspection method was proposed to classify and count dragon fruit flowers, immature fruits (green fruits), and mature fruits (red fruits) in a dragon fruit plantation. The approach involves three key steps: (1) utilizing the YOLOv5 network for the identification of different dragon fruit categories, (2) employing the improved ByteTrack object tracking algorithm to assign unique IDs to each target and track their movement, and (3) defining a region of interest area for precise classification and counting of dragon fruit across categories. Experimental results demonstrate recognition accuracies of 94.1%, 94.8%, and 96.1% for dragon fruit flowers, green fruits, and red fruits, respectively, with an overall average recognition accuracy of 95.0%. Furthermore, the counting accuracy for each category is measured at 97.68%, 93.97%, and 91.89%, respectively. The proposed method achieves a counting speed of 56 frames per second on a 1080ti GPU. The findings establish the efficacy and practicality of this method for accurate counting of dragon fruit or other fruit varieties.

Theobroma subincanum (cupuí) is a fruit species native to the Amazon region. Fruits are enjoyed by local people and consumed both as fresh fruit such as juice, nectar or soft drinks. Reproductive biology studies provide contributions to conservation strategies and plant improvement. The present study aimed to analyze the stigmatic receptivity and pollen viability of T. subincanum. This study was developed in a forest fragment located in the urban perimeter of the municipality of Alta Floresta, MT. In the flowering period, flower buds or flowers were collected in seven different times, as follows: 10 pm, 02 am, 06 am, 10 am, 2 pm, 6 pm, and 10 pm. Pollen viability was estimated by reactive Alexander (1969) and stigmatic receptivity using 3% hydrogen peroxide. Pollen viability averages were submitted to analysis of variance, while stigmatic receptivity was analyzed by average percentage in each interval. Four floral stages were characterized based on flower opening, and from 6 am, fully opened flowers have already been found (stage IV). The percentage of pollen viability was not affected by collection times. In the stigmatic receptivity analysis, it was observed that in all floral stages, stigma was receptive; however, the highest percentages of stigmatic receptivity were found from 2 am to 10 am of the same day, which is the most propitious time for fertilization. Pollen collection of T. subincanum may be performed in any of schedules evaluated in this study, since it is held with high viability percentage.

<i>Hylocereus undatus</i> (dragon fruit).

Occurrence of Anthracnose Disease Caused by<i>Colletotrichum siamense</i>on Dragon Fruit (<i>Hylocereus undatus</i>) in Andaman Islands, India

Dragon fruits are usually consumed by people directly or being processed into juice. Therefore, the major by-product of dragon fruits is the peel. As by-product, dragon fruit peels have higher antioxidant level than pulp especially for White Dragon Fruits (Hylocereus undatus). This research is carried out in order to evaluate the antioxidant level and sensory of dragon fruit peel tea which produced through a partially fermented process. The objective of this research is to investigate the effect of withering time and rolling time on antioxidant level and sensory of dragon fruit peel tea. Withering time varied in 30, 60, and 120 min while the rolling time varied in 10, 20, and 30 sec. 2, 2, diphenyl-1-picrylhydrazil (DPPH) assay showed that radical scavenging activities of dragon fruit peel tea infusion increased with the longer withering time and shorter rolling time. Likewise the total phenol content (TPC) assay demonstrated the amount of phenol increased with the longer withering time and shorter rolling time. There were found that the dragon fruit peel had 29.58% in proportion compared with the whole fruit and vitamin C content in the peel higher than that in the pulp. The longer withering time and shorter rolling time will increase the phenol total content, antioxidant activity, and the lightness color, but decrease the acidity degree of tea infusions. In addition, the withering time was 120 min and rolling time was 10 sec had higher Antioxidant activity 41.19% and the total phenol 55.93 mg/L.

Background and AimsMale fertility is often suboptimal in parthenocarpic banana cultivars, hindering their use as male parents in current banana breeding schemes. Next to genotype-specific traits, such as ploidy and structural heterozygosity, inflorescence developmental age and environmental factors can significantly influence male reproductive performance.MethodsIn this study, pollen viability, germination capacity and diameter, were closely monitored throughout the entire male flowering phase of Musa acuminata wild diploids and diploid and triploid cultivars. Additionally, environmental parameters, including temperature, light radiation and humidity, were monitored up to 40 days before anthesis to determine their influence on microgametogenesis.Key ResultsWild accessions showed a gradual reduction in pollen germination over the flowering period. High light radiation prior to pollen mitosis I and II reduced germination capacity, whereas during meiosis it negatively affected pollen viability. Conversely, in cultivated bananas, pollen traits improved with the developmental age of the male inflorescence. In these cultivars, higher temperatures during meiosis enhanced pollen diameter, viability and germination rates.ConclusionsThese findings indicate that both inflorescence maturity and specific environmental conditions during pollen development significantly influence pollen quality in bananas. Pollen performance could be optimized in wild diploids by obtaining pollen in the first months of the male flowering phase and shielding the plants from high light intensities, whereas for cultivars the pollen should be harvested towards the end of the male flowering phase, and a heat treatment during meiosis could lead to higher pollen quality and thereby increase breeding success.

Adenium obesum (Forssk.) Roem. &amp; Schult., popularly known as desert rose, has become a valuable ornamental plant. In floriculture, the production of hybrids is prioritized. Hence, knowledge on floral biology and sexual reproduction of the target species is fundamental. The objectives of this study were: (1) to test sucrose concentrations and temperatures for in vitro germination of A. obesum pollen grains; (2) to identify the effect of temperature on the viability of A. obesum pollen grains; and (3) to evaluate the viability of pollen grains and stigma receptivity in pre-anthesis, at flower opening, and 72 h post-flower opening in three accessions of A. obesum. A significant relationship between temperatures and sucrose concentrations was observed in the in vitro germination test. The highest percentage of in vitro germination of pollen grains, 39.81%, was observed at an estimated temperature of 26.05 °C. Desert rose accessions maintained in biochemical oxygen demand (BOD) chambers at 30 °C during a 16-h light photoperiod showed faster flowering, and temperatures ≥ 25 °C induced pollen grain viability percentages above 69%. Temperature is one of the most important abiotic factors, influencing mainly in pollen germination, pollen tube growing and in efficiency fertilization. The ICA-wd accession stood out and can be considered a pollen donor in artificial pollination. The stigmas of flowers were receptive from a day before flower opening until three days after. The two parameters presented above, stigma receptivity and pollen viability, allow inferences about the appropriate time for successful pollination and subsequent fertilization in desert roses.

Pollen viability and stigma receptivity are prerequisites for successful pollination and seed set in flowering plants. In this study, the pollen viabilities and stigma receptivities of nine Lilium genotypes (six cultivars and three species native to China) were assayed by in vitro pollen germination and the benzidine-H2O2 method, respectively. Embryo sac development during anthesis was observed to further ensure the timing of controlled pollination. In addition, the relationship between stigma secretion and stigma receptivity was studied to estimate the pollination time based on phenotype. Anthers cracked on the day of flowering in all genotypes, but pollen germination during anthesis was not observed in Asiatic hybrids excepted for ‘Tiny pudhye’, which exhibited low pollen viability for a short period of time (from 0 to 1 day after anthesis). In the other genotypes, pollen germination rates were highest on anthesis (five of seven genotypes), 0–1 day after anthesis (L. sulphureum), or 0–2 days after anthesis (one Longiflorum hybrid), and then gradually decreased with days after anthesis. While, stigma receptivity first increased and then decreased during anthesis. For most genotypes, stigmas began to be receptive 1 day after anthesis, and all genotypes exhibited stigma receptivity at 2 days after anthesis. The durations of stigma receptivity and strongest stigma receptivity, were genotype dependent, and were 5–8 days and 1–4 days, respectively. Moreover, on the first flowering day, 6 of 7 genotypes had mature embryo sacs, and at the time at which stigmas began to be receptive, all tested genotypes had mature embryo sacs. Some Lilium genotypes showed stigma secretion, which can be a sign of stigma receptivity. Stigmas became receptive and reached highest receptivity within 1 day of the first appearance of secretion on the surface of the stigma and at peaking, respectively. The results of this study are valuable for the implementation of successful Lilium breeding programs.

Aji SP, Anandito BK, Nurhartadi E. 2013. Study of addition of various types of honey as alternative sweetener in white dragon (Hylocereus undatus) juice drink. Biofarmasi 11: 13-18. Indonesia is a tropical country, so people tend to consume lots of water to refresh the body. Along with the development of technology and the desire of people to come back to healthy life, it is necessary to manufacture beverage that have functional value. Dragon fruit has a large nutritional content. Dragon fruit contains several bioactive components, such as: anthocyanin, vitamin C, beta-carotene and soluble fiber in the form of pectin. Therefore, the processing of dragon fruit into juice that contains bioactive components is potential. In general, fruit juice beverage use a sweetener based on sucrose, therefore in this study it was used honey as an alternative sweetener that has a functional value. This research aimed to study the making of white dragon juice (Hylocereus undatus) using honey sweetener types of rambutan, kelengkeng and randu, and to analyze its chemical characteristic (vitamin C and antioxidant) and sensory properties (taste, color, aftertaste, overall). In this study, it was used white dragon fruit and various types of honey such as randu honey, rambutan honey and kelengkeng honey with the concentrations of 5%, 10% and 15%, respectively. The results showed that dragon fruit juice with the addition of rambutan honey contained vitamin C and antioxidant greater than the addition of randu and kelengkeng honey. The addition of honey with the different concentrations (5%, 10%, 15%) could also increase vitamin C and antioxidant contents in the produced functional beverage. The higher concentration of honey that added, the higher produced vitamin C and antioxidant contents. Meanwhile, the sensory test results of color, taste, aftertaste and overall parameters for dragon fruit juice samples with the addition of rambutan, rambutan and kelengkeng honey, the average of panelists gave a like score. But, the higher concentration of honey that added, the sensory results indicated the panelist preference decreased. According to the results of the panelist study showed the level of fondness in all types of honey at a concentration of 10%.

The dragon fruit peels (Hylocereus undatus) are typically thrown away as agricultural waste. The disposal of bio-wastes, like peels from dragon fruit and microbiological contamination during their mass breakdown, all contribute to environmental degradation. Peel can be used to extract naturally occurring colour for pigments. The objective of this study is to investigate the feasibility of using the peel of Hylocereus undatus as a coating material for wound healing. The extraction method and potential uses of the pigments derived from the peel will be explored. The study aimed to determine the phytochemical components of Hylocereus undatus (peel) extract and the peel can be utilized as a raw material for pigment extraction due to the betalain content. With the use of a magnetic stirrer extraction, the peel of Hylocereus undatus was extracted with aqueous extraction. Thin layer chromatographic techniques are used to identify the pigment components. In the present study, we recorded both UV-VIS and FT-IR profile of peel extract to known the various phytoconstituents and determine the functional group present in Hylocereus undatus (white dragon fruit). The pigment needs to be applied to the wound gauze, and the stain resistance should be evaluated by determining how well the wound gauze can withstand contamination from the outside coating. Furthermore, the pharmaceutical and nutraceutical sectors are interested in Hylocereus undatus peel due to its components, which may have potential health applications such as anti-inflammatory, antioxidant, antibacterial, and anti-cancer characteristics

Pitaya, commonly known as dragon fruit, has generated considerable consumer interest because of its attractive color and micronutrient content. The present study investigated the total polyphenol and flavonoid content, antioxidant activity against various free radicals, and antiproliferative effect on several cancer cell lines of extracts of flesh and peel of white and red pitayas, collected from Jeju Island, Korea. The total polyphenol and flavonoid contents of 80% methanol extracts of red pitaya peel (RPP) and white pitaya peel (WPP) were approximately 3- and 5-fold higher than those of red pitaya flesh (RPF) and white pitaya flesh (WPF), respectively. Overall, the total flavonoid and polyphenol contents of these extracts were RPP>WPP>RPF>WPF and WPP>RPP>RPF>WPF, respectively. In addition, a study involving nontargeted high-performance liquid chromatography coupled with a photodiode array and electrospray ionization mass spectrometry (HPLC-PDA-ESI-MS) of different pitaya extracts indicated the presence of phenolic, hydroxycinnamic acid derivatives, flavonol glycosides, betacyanin, and its derivatives with a few unknown compounds. Separately, peel extracts of both red and white pitayas showed higher 2,2-diphenyl-1-picrylhydrazyl, hydroxyl, and alkyl radical-scavenging activity than did the corresponding flesh extracts. Both peel extracts also showed stronger antiproliferative activity against AGS and MCF-7 cancer cells than either flesh extract. There was a direct correlation between the phenolic content and antioxidant effect, but no correlation observed between antioxidant activity and antiproliferative activity. These results suggest that the peel of white and red pitaya may be a valuable ingredient in foods and may also be useful in cosmetic, nutraceutical, and pharmaceutical applications.

Dragon fruits are usually consumed by people directly or being processed into juice. Therefore,the major by-product of dragon fruits is the peel. As by-product, dragon fruit peels have higherantioxidant level than pulp especially for White Dragon Fruits (Hylocereus undatus). Thisresearch is carried out in order to evaluate the antioxidant level and sensory of dragon fruitpeel tea which produced through a partially fermented process. The objective of this researchis to investigate the effect of withering time and rolling time on antioxidant level and sensory ofdragon fruit peel tea. Withering time varied in 30, 60, and 120 min while the rolling timevaried in 10, 20, and 30 sec. 2, 2, diphenyl-1-picrylhydrazil (DPPH) assay showed that radicalscavenging activities of dragon fruit peel tea infusion increased with the longer withering timeand shorter rolling time. Likewise the total phenol content (TPC) assay demonstrated theamount of phenol increased with the longer withering time and shorter rolling time. Therewere found that the dragon fruit peel had 29.58% in proportion compared with the whole fruitand vitamin C content in the peel higher than that in the pulp. The longer withering time andshorter rolling time will increase the phenol total content, antioxidant activity, and thelightness color, but decrease the acidity degree of tea infusions. In addition, the withering timewas 120 min and rolling time was 10 sec had higher Antioxidant activity 41.19% and the totalphenol 55.93 mg/L.

Postharvest quality of Dragon fruit ( Hylocereus undatus) following disinfesting hot air treatments