Flower Anthesis Research Articles

Contribution to the Study of Malagasy Orchids. XXXIX. Two New Species of Bulbophyllum from Madagascar

Two new species of Bulbophyllum Thouars, B. psittacinum Verlynde & Ramand. and B. vespertilioides Verlynde & Ramand. (Orchidaceae), are recognized and described. Both species are endemic to Madagascar and were found in the Ankerana forest, part of the Ankeniheny-Zahamena corridor (CAZ) protected area in the eastern escarpment forests. These two species belong to section Pantoblepharon Schltr.; B. psittacinum differs from the rest of the section by its conjoined lateral sepals and B. vespertilioides by its larger pseudobulbs, longer inflorescence, and number of flowers. Taxonomic treatments of both species with descriptions, illustrations, distribution, and habitat information as well as preliminary IUCN Red List assessments are provided.

Evaluating the role of insect pollinators in the viability of true seeds of shallot in tropical agroecosystems

Pollen transfer in tropical agroecosystems to increase seed production has received limited research, notably on shallot pollination and insect pollinators. This study evaluated how insect pollinators optimize shallot seed production in tropical agroecosystems, i.e. Batu and Malang Districts in Indonesia. This study was conducted from June to October in 2023. We examined pollinator diversity, foraging behavior, and the effectiveness of dominating insect pollinators during umbel flower anthesis, as well as visiting insect foraging and visiting patterns. We assessed pollinator effectiveness by comparing visitation rates under four treatments. A total of 21 insect species belonging to three orders visited the shallot flowers, of which 14 species have the potential to act as pollinators. Apis cerana Fabricius, 1793 (Hymenoptera: Apidae) and Lucilia sericata (Meigen, 1826) (Diptera: Calliphoridae) emerged as potentially effective pollinators. Air temperature significantly influenced pollinator activity in visiting anthesis umbels. Evaluations of pollinator efficiency showed that A. cerana was more efficient than L. sericata in promoting the production of true shallot seed and has a significant role in ensuring high-quality pollination. This highlights the necessity of comprehending the specialized contributions of pollinators for shallot seed production.

Comparative chemometric modeling of fresh and dry cannabis inflorescences using FT-NIR spectroscopy: Quantification and classification insights.

Cannabis sativa L. inflorescences are rich in cannabinoids and terpenes. Traditional chemical analysis methods for cannabinoids and terpenes, such as liquid and gas chromatography (using UV or MS detectors), are expensive and time-consuming. This study explores the use of Fourier transform near-infrared (FT-NIR) spectroscopy combined with chemometric approaches for classifying cannabis chemovars and predicting cannabinoid and terpene concentrations for the first time in freshly harvested (wet) cannabis inflorescence. The study also compares the performance of FT-NIR spectroscopy on wet versus dry cannabis inflorescences. Spectral data from 187 samples across seven cannabis chemovars were analyzed using partial least squares-discriminant analysis (PLS-DA) and partial least squares-regression (PLS-R) models. The PLS-DA models effectively classified chemovars and major classes using only two latent variables (LVs) with minimal overfitting risk, with sensitivity, specificity, and accuracy values approaching 1. Despite the high water content in wet cannabis inflorescence, the PLS-R models demonstrated good to excellent predictive capabilities for nine cannabinoids and eight terpenes using FT-NIR spectra for the first time, achieving cross-validation and prediction R-squared values greater than 0.7, ratio of performance to interquartile range (RPIQ) exceeding 2, and a RMSECV/RMSEC ratio below 1.24. However, the low-cannabidiolic acid submodel and (-)-Δ9-trans-tetrahydrocannabinol model showed poor predictive performance. Some cannabinoid and terpene prediction models in wet cannabis inflorescence exhibited lower predictive capabilities compared with previously published models for dry cannabis inflorescence. These findings suggest that FT-NIR spectroscopy can be a viable rapid on-site analytical tool for growers during the inflorescence flowering stage.

Indicators of woody plants and soil in the urbanised environment of the Southern Urals (green zone of Ufa, Russia)

ABSTRACT The study investigates biometric indicators of assimilation and reproductive organs of coniferous and deciduous trees in urban environments: leaf area, inflorescence flower count, stipule length of Tilia cordata Mill. and needle length and weight of Scots pine (Pinus sylvestris L.). Samples of wood, needles, leaves and soil from the planting sites were analysed for 17 chemical elements, including Hazard Class I elements (Arsenic, Lead, Cadmium, Mercury, Selenium) and Hazard Class II elements (Chromium, Cobalt, Nickel, Copper, Molybdenum, Antimony). Tree plantations decreased airborne dust by 30–40% compared to open areas. Concentrations of PM2.5 and PM10 particles showed a direct correlation with busy roads (p < 0.05). In instances of environmental degradation, healthy trees exhibited in needle an increase in biomass and a reduction in weight and length. Consequently, forestry measurements and the impact of the urban environment require specific and individual monitoring of trees, rather than a general assessment of plantations.

Field evaluation of biostimulants on growth, flowering, yield, and quality of snap beans in subtropical environment

The cultivation of snap beans (Phaseolus vulgaris L.) in subtropical regions faces environmental challenges leading to potential declines in yield. This study explores the efficacy of biostimulants as a solution, specifically investigating spraying treatments with 6-benzylaminopurine (6-BA), chitosan (Ch), triacontanol (TRIA), and potassium silicate (KSi) on the snap bean cv. Paulista. Over two growing seasons with late sowing and elevated summer temperatures, the research assesses growth, flowering, yield, and quality. Notably, 5 ppm TRIA demonstrates the most significant impact on plant growth and leaf nutrient content. Treatments with 40 ppm 6-BA, 5 ppm TRIA, or 200 ppm KSi exhibit notable effects on inflorescence flower count and flowers per plant. These treatments prove most effective for crucial green pod yield measures, including the number and weight of marketable pods. Moreover, 40 ppm 6-BA or 5 ppm TRIA significantly enhances pod characteristics, such as length, diameter, and weight, consistently improving over both seasons. Particularly, 5 ppm TRIA outperforms in enhancing the chemical quality of pods throughout the study. Overall, the findings suggest that the application of 5 ppm TRIA offers the most favorable enhancements for the growth, flowering, productivity, and quality of snap bean plants in subtropical field conditions.

Evaluation Trial of IVY Gourd (Coccinia grandis L.) Varieties in Prayagraj Agro Climatic Condition

The current trial on commenced in February 2023 at the Horticulture Research Field, Department of Horticulture, Naini Agricultural Institute, Sam Higginbottom University of Agriculture, Technology and Sciences, Prayagraj, Uttar Pradesh. This experiment employed a Random Block Design (RBD) with seven varieties replicated three times. The varieties, namely V₁ (Arka Neelachal Khunki), V₂ (Arka Neelachal Sabuja), V₃ (Local Geda), V₄ (Local Denga), V₅ (Surekha), V₆ (CHIV-8), and V₇ (CHIV-9), were assessed based on various growth, yield, and quality parameters. These parameters included vine length, petiole length, appearance of the first female flower anthesis, internode length, fruit length, fruit diameter, average fruit weight, number of fruits per plant, number of seeds per fruit, fruit yield per plant, fruit yield in tonnes per hectare, total soluble solids (TSS), ascorbic acid content, fruit shape, and colour. From the different parameters it was concluded that all the seven varieties showed significant performance in almost all the characters. The variety V₂, Arka Neelachal Sabuja, exhibited superior characteristics in various parameters, including vine length (310.66 cm), internode length (12.71 cm), fruit length (6.11 cm), average fruit weight (21.07g), number of fruits per plant (422), number of seeds per fruit (122), fruit yield per plant (8.53 kg), fruit yield per hectare (17.36t/ha), total soluble solids (TSS - 4.31), and had the minimum days taken for the first female flower anthesis (32.67 days). It featured an ovoid-shaped fruit with dark green fractured strips. On the other hand, variety V₁, Arka Neelachal Khunki, demonstrated maximum petiole length (8.03 cm) and ascorbic acid content (15.30 mg/100g of fruit pulp). The fruit was uniform and cylindrical in shape with light green colour and white stripes.

Correlation Coefficient and Path Analysis of Yield and It’s Components Analysis in Pumpkin (Cucurbita moschata Duch ex. Poir)

The current experiment was designed to evaluate the correlation coefficient and path analysis of yield and its components in pumpkin (Cucurbita moschata Duch ex. Poir) among various genotypes. The study involved 35 distinct genotypes, including a control, to measure both quantitative and qualitative traits. It was conducted in a randomized block design with three replications at Acharya Narendra Deva University of Agriculture and Technology, Kumarganj, Ayodhya, during the summer of 2021. Observations included the node number at first staminate and pistillate flower anthesis, days to anthesis of both flower types, days to first fruit harvest, fruit polar length, fruit equatorial circumference, flesh thickness, number of fruits per plant, average fruit weight, and total fruit yield per plant. The genotypes were assessed for yield through correlation coefficients and path analysis, indicating promising breeding values as supported by the analysis of variance. Among the 35 genotypes, four yielded significantly more than the highest-performing control, Narendra Agrim.

Trait Association and Path Analyses for Yield and Its Attributes in Ridge Gourd Commercial Hybrids (Luffa acutangula L.)

This study aims to explore the relationship between several traits among 18 ridge gourd hybrids. It was carried out during the rabi season of 2021–2022, at Pandit Jawaharlal Nehru College of Agriculture and Research Institute, Karaikal, U.T. of Puducherry. Twenty yield-related qualities were assessed using a randomized block design with two replications in order to determine the associations among various characters. The yield per vine was found to have a highly significant and positive correlation with the following variables: vine length at final harvest, number of primary branches vine-1, number of female flowers vine-1, days to final harvest, fruit length, fruit girth, number of seeds fruit-1, total number of harvest, number of fruits vine-1 and weight of individual fruit. Path analysis revealed that the characters such as number of female flowers vine-1, days to first female flower anthesis, total number of harvest, sex ratio, total soluble solids, days to first male flower anthesis, vine length at final harvest, number of seeds fruit-1, days to first harvest, number of primary branches vine-1, fruit length, fruit girth, number of seeds fruit-1, number of fruits vine-1 and weight of individual fruit are considered as important traits which directly and indirectly influences towards yield. It implies that the characters strongly influence the yield vine-1 and hence selection for these traits would be considered important in selection of hybrids for yield.

Performance of Different Pumpkin (Cucurbita moschata) Hybrids for Growth, Yield and Quality under Prayagraj Agro-Climatic Condition

An experimental material comprised of 10 hybrid of pumpkin viz., SADABAHAR, PK-2507 F1hybrid, P6 F1 hybrid, P6 Gold F1hybrid, SS-76 F1 hybrid, SURAJ F1hybrid, SIPRA F1 hybrid, PRITVI F1hybrid, LHP-SINGHAM F1hybrid, SW-1001 F1hybrid.The investigation was carried out in a Randomized Block Design with three replications. Main Experiment Station of the Department of Vegetable Science at Sam Higginbottom University of Agriculture, Technology and Sciences Prayagraj (U.P) during the spring season. Present investigation reveuled that pumpkin hybrids viz, vine length cm (SW-1001 F1hybrid), no of braches (PK-2507 F1hybrid) performance best in term of growth. Two hybrids namely LHP-SINGHAM F1hybrid and SW-1001 F1hybrid performance best in term of yield. For the maximum number of fruit per plant and minimum node number for the first staminate flower anthesis was observed in the case of LHP-SINGHAM F1hybrid which is promoted to earliness and high yielding. Two hybrids namely P6 Gold F1hybrid TSS (°Brix), LHP-SINGHAM F1hybrid Vitamin c /100gm.

Combining Ability Analysis of Yield and Quality Traits in Pumpkin [Cucurbita moschataduch. Ex Poir

The present analysis was carried out with aims to estimate the general and specific combining ability of pumpkin involving six parents namely, Arka Chandan (P1), Ambili (P2), Arka Suryamukhi(P3), Pusa Vishwas (P4), CO 2 (P5) and CO 1 (P6) and 30 F1 hybrids obtained through full diallel analysis in randomized block design with three replication. The observation were recorded for eighteen traits viz., vine length, node number at which first male flower anthesis, node number at which first female flower anthesis, number of primary branches vine-1, days to first male flower anthesis, days to first female flower anthesis, number of male flowers vine-1, number of female flowers vine-1, sex ratio, number of fruits vine-1, fruit weight, polar diameter of fruit, equatorial diameter of fruit, flesh thickness, 100 seed weight, carotene content, total soluble solids and yield vine-1.. The analysis of variance for combining ability among various traits in pumpkin revealed that there were significant differences for all the traits. Among the parents, Ambili was the best general combiner for number of fruits vine-1, yield vine-1 and yield contributing traits. The highest desirable SCA were obtained from a cross of Ambili x Arka Suryamukhi for yield and attributing traits, which was the best and promising hybrid.

Urban environment decreases pollinator availability, fertility, and prolongs anthesis in the field bindweed (Convolvulus arvensis Linnaeus, 1753)

ABSTRACT Urbanization alters the natural environment, with broad negative impacts on living organisms. Urbanization can also disrupt plant-pollinator networks by reducing the abundance and diversity of invertebrates. Firstly, I investigated whether the field bindweed (Convolvulus arvensis) is an obligatory entomophilous plant because previous reports were ambiguous. Secondly, I investigated how the obligatory entomophilous plant, field bindweed, responds to urbanization by comparing the flowering duration (anthesis) and the reproductive success of field bindweeds in urban and rural populations. Unlike cross-pollinated flowers and controls, flowers experimentally prevented from pollination and self-pollinated flowers did not produce seeds, suggesting that the field bindweed is self-incompatible and obligatory entomophilous. The abundance of urban pollinators was 5–6 times lower than the abundance of rural pollinators, and flies (Diptera), beetles (Coleoptera) and moths (Lepidoptera) were significantly more negatively influenced by the urban environment than hymenopterans (Hymenoptera). Urban plants showed significantly longer anthesis duration and lower reproductive success than rural plants. Illuminance and low pollinator abundance were negatively associated with the duration of the anthesis, but relative humidity did not affect the anthesis. Prolonged duration of the anthesis may be an adaptation to pollinator scarcity because more prolonged flowering increases the likelihood of pollination. Future research should unravel whether the longer anthesis of urban flowers is determined by behavioral plasticity or by the evolutionary selection of plants with a genetically determined longer anthesis.

Components of Genetic Variation for Yield and its Attributing Traits in Bottle Gourd (Lagenaria siceraria (Mol.) Standl.)

An investigation was carried out to assess the gene action in bottle gourd for twenty- three characters at Main Experiment Station, Department of Vegetable Science, A.N.D.U.A.&amp;T., Kumarganj, Ayodhya (U.P). during Zaid 2022 using 12 genotypes, nine lines i.e., Narendra Rashmi, NDBG-17, Pusa Naveen, NDBG-21, Punjab Komal, NDBG-28, NDBG-65-2, NDBG-105, NDBG-Sel-2 and three testers i.e., Narendra Prabha, Narendra Kamna, Narendra Pooja and their 27 hybrids obtained through line × tester mating pattern. The variances due to sca (σ2 s) were higher than variance due to gca (σ2g) for all the characters. The value of dominance genetic variances (σ2 D) were larger than additive genetic variance (σ2 A), indicating the presence of dominance and over dominance effects and preponderance of non-additive gene action .The heritability in narrow sense was low for most of the traits except fruit length, days to first staminate flower anthesis and primary branches per plant where high estimate of heritability in narrow sense with low genetic advance were recorded, indicating the presence of non-additive gene action accompanied by environmental influence.

Genetic Estimations of Available Quality Traits for Improved Growth Yield of Pumpkin (Cucurbita moschata Duch) in Kumarganj, India

Pumpkin is one of the most economically important and nutritious member of the family Cucurbitaceae. The present investigation was conducted to evaluate genetic variability, heritability and genetic advance in per cent of mean among the 30 genotypes including one check variety (Narendra Agrim) for 21 qualitative and quantitative traits. The experiment was conducted in randomized block design with three replication ,the observations were recorded on the traits like days to 50% staminate flower anthesis , days to 50% pistillate flower anthesis, node no. to first staminate flower anthesis, node no. to first pistillate flower anthesis, vine length, no. of nodes, no. of primary branches, inter-nodal length, days to first fruit harvest, polar circumference, equatorial circumference, flesh thickness, cavity, average fruit weight, no. of fruits per plant, total soluble solids, reducing sugars, non reducing sugars, total sugars, fruit yield per plant. The analysis of variance for the design of experiments indicated highly significant difference among the genotypes for all 21 characters. The four genotypesviz.NDPK-17-12-1,NDPK-23,NDPK-P-6 and NDPK-32-1-2 were found significantly superior for fruit yield per plant over the check variety (NarendraAgrim).The PCV was higher than the GCV and was found highest for the trait fruit yield per plant, the presence of high heritability in broad sense along with high genetic advance in per cent of mean were observed for fruit yield per plant.Therefore,from the above obtained results it can be concluded that the characters will result in effective crop improvement for higher yield and yield contributing traits.

Polinização de flores da cultivar de morango San Andreas

Abstract The objective of this work was to determine the optimal day for pollinating the flowers of the San Andreas strawberry cultivar after flower anthesis. The study was carried out in two periods (summer and fall), on a commercial farm. A total of 12 flower buds were monitored and photographed in each of the following 11 treatments: manual cross-pollination (MCP) on the first to fifth day after flower anthesis (MCP1 to MCP5), natural pollination (NP) on the first to fifth day after flower anthesis (NP1 to NP5), and self-pollination. After pollination, the flowers were bagged until the development and maturation of the flower receptacle. Subsequently, the fruits were harvested, quantified, and subjected to evaluations to determine biometry, degree of deformity, and the percentage of fertilized achenes. The flowers of the San Andreas cultivar remain open during five days, when the beginning of the development of the flower receptacle can already be observed. The optimal days for strawberry flower pollination through MCP or NP are the first two days after anthesis.

Effect of shading, organic fertilizer and Gibberellic acid on the flowering growth of (Lavandula angustifolia) growing in Kalar city

The experiment was conducted in the city of Kalar for the period from April 1, 2022 to September 1. The experiment included three factors. The first factor is the percentage of shading at two levels open field and 50% lath house. The second factor was organic fertilizer for poultry (Penguin) at three levels (0, 25, 50) gm.plant-1, and the third factor was spraying with Gibberellic acid at three levels (0, 250, 500) mg. L-1. The experiment was designed according to a completely randomized design (R.C.B.D.). The results showed the following. The 0% shading treatment had a significant effect on the characteristics of the number of flower clusters (19,836 clusters per plant), the length of the flower clusters (23,327 cm), the length of the flower (7,768 cm), and the fresh weight of the flower. Inflorescence (0.390 g), and the number of flowers in one inflorescence (36,095 flowers. Pink inflorescence. Plant-1). As for the effect of organic fertilizer (Penguin), both concentrations (25 and 50 gm Plant-1) had a significant effect. Characteristics of flower spike length (23.239 and 23.217 cm). Inflorescence length (6.699, 7.133 cm), inflorescence fresh weight (0.292, 0.298 g), and number of flowers in inflorescence (30.438, 30.715 flowers. inflorescence. plant-1), respectively. As for the effect of spraying with Gibberellic acid, the concentration treatment (250 and 500 mg L-1) significantly affected the length of the flower spike (22.812 and 23.215 cm). Respectively, treatment with 250 mg.L-1 significantly affected the length of the inflorescence (6.977 cm) and the number of flowers per inflorescence (30.656 flowers.Flower-1).

Pollen available during anthesis of Hylocereus undatus flowers

Pitahaya (Hylocereus spp) is a fruit that, due to the characteristics of its demand, both for fresh fruit and for industrial consumption, has detonated its development in various countries. However, it presents various self-incompatibility mechanisms that impact productivity. Therefore, the viability of pollen was analyzed during the anthesis (or flowering period)of two white-fleshed H. undatus cultivars, taking pollen samples for 13 hours, from the beginning of the anthesis in the afternoon, until it ends the following day. The method used was staining with tetrazolium salt (2,3,5-triphenyltetrazolium chloride) or TZ. The results showed that there is no viable pollen at the beginning of the anthesis. At 09:00 pm the viability began to grow slowly and after 12:00 am it doubled and the viability accelerated, marking the highest from 02:00 to 04:00 am. It was possible to observe the consistency of the pollen that begins with a phase I with humid pollen without viability, up to another with lower humidity with low viability (phase II). Phase III observed very granular mealy pollen, easy to handle precisely when the staining readings marked the viability of 93 % to 95 %. Subsequently, the viability decreases until it disappears when the floral structure begins to dehydrate.

Studies on Genetic Variability, Correlation Analysis in Mithipagal (Momordica charantia var. muricata) Genotypes

The present investigation was carried out in Tamil Nadu Agricultural University, Coimbatore to study the “Genetic variability and correlation analysis in Mithipagal (Momordica charantia var. muricata) genotypes”. Observations on vine length, days to male flower inflorescence, days to female flower inflorescence, node of first male flower appearance, node of first female flower appearance, sex ratio, number of fruits per vine, fruit weight, fruit length, fruit girth, number of seeds per fruit, yield per vine, ascorbic acid, protein content, iron content and total soluble solids were recorded. Variability and correlation analysis among genotypes were examined. The results, showed that yield per plant had high positive and high significant correlation with fruit weight, fruit girth, number of seeds per fruit, vine length and fruit length. High genotypic co-efficients of variation (GCV) were found for fruit yield per vine, fruit weight, TSS, fruit length, vine length, fruit girth, node of first female flower, number of fruits per vine, number of seeds per fruit, iron, protein content when genetic characteristics were taken into account, However low GCV was found for days to the first male and female flowering. Phenotypic variants were always greater than genotypic variances. For traits such asyield per vine, fruit weight, TSS, fruit length, vine length, fruit girth, number of fruits per vine, number of. seeds per fruit, node of first male flower appearance, node of first female flower appearance, sex ratio, vitamin C, protein, iron content high heritability was found together with high genetic advance in percent of mean, indicating that these features are under additive gene control and hence selection for genetic improvement would be successful. Node of first male flower appearance showed low heritability combined with low genetic advance as a percentage of the mean indicating that non-additive gene effects were involved in the expression of this trait and hence selection for such a trait could not be beneficial. The knowledge of these statistical factors would be useful in identifying genotypes with greater yield potential that might be used in the improvement of mithipagal.

Deciphering genetic variability in melon (Cucumis melo L.) using morphological characters

Genetic variability, heritability and genetic advance were investigated in 96 melon (Cucumis melo L.) genotypes from 4 horticultural or 6 varietal groups using 10 quantitative traits. The results of the analysis of variance showed that there was enough variation among the genotypes for all the attributes. The highest phenotypic and genotypic coefficients of variations (PCV and GCV) were observed for node to first male flower (40.98 and 31.3%), average fruit weight (36.23 and 30.8%) and total soluble solids (28.01 and 26.67%), while days to first male flower anthesis (10.49 and 8.85%) and days to first female flower anthesis (8.86 and 7.4%) had the least coefficients of variations. The high difference between PCV and GCV estimates exhibited that environmental factors had more influence on trait expression. High heritability coupled with high-moderate GAM was observed for TSS and flesh thickness, indicating that additive genes govern these traits and that these traits could be effectively breed through selective improvement. Nine promising genotypes were identified for further breeding for earliness and lateness in order to extend melon supply in the market.

Evaluation of Ivy Gourd (Coccinia grandis L) Genotypes under Prayagraj Agro Climatic Conditions

The present investigation entitled “Evaluation of Ivy gourd (Coccinia grandis L) genotypes under Prayagraj agro climatic conditions” was carried out from October, 2022 to March 2023 at Horticultural Research Field, Department of Horticulture, Naini Agricultural Institute, Sam Higginbottom University of Agriculture, Technology And Sciences, Prayagraj, U.P. The experiment was laid out in randomized block design with seven genotypes in three replications. The genotypes namely G1-Arka Neelachal Khunki, G2-Arka Neelachal Sabuja, G3-Local Geda, G4-Local Denga, G5-Surekha, G6- CHIV-7 and G7-CHIV-8 were evaluated. It was concluded that all seven genotypes showed a significant performance on almost all the growth and yield characters as well as quality of Ivy gourd. The genotype G2-Arka Neelachal Sabuja was found superior in terms of vine length (315.11 cm), petiole length (6.37 cm), internodal length (12.71cm),fruit diameter (2.87 cm), average fruit weight (21.08 g), No. of seeds per fruit (122), No. of fruits per plant (422), fruit yield per plant (8.82 kg) ,fruit yield per hectare (17.35 t/ha), TSS (4.33), Ascorbic acid (15.34 mg/100g) and minimum days taken for first female flower anthesis (35.17 days) whereas maximum fruit length was obtained from genotype G1- Arka Neelachal Khunki (6.12 cm). Among the genotypes, highest gross return (Rs/ha) (3,47,000), net return (Rs/ha) (1,90,140), benefit cost ratio (2.21) was also obtained from genotype G2 i.e Arka Neelachal Sabuja.

DOMINANCE AND HETEROSIS IN F1 WATERMELON HYBRIDS

Purpose. To evaluate heterosis in new F1 hybrids and to select the best ones with the greatest dominance and heterosis for the "growing period length", "yield", "marketability" and "mean marketable fruit weight" traits for further use in breeding for heterosis. Object. Twenty-seven F1 watermelon hybrids and 22 parents. Methods. General scientific, measuring and weighing, computational and statistical. Results. F1 watermelon hybrids and their parents were screened for the following characteristics: lengths of interphase periods, total yield, marketability, and mean marketable fruit weight. Analysis of the growing period and its parts showed that in the hybrids the "emergence - ripening" period ranged 71 to 80 days in 2021 and 60 to 84 days in 2022. The variation limits were from 6 to 24 days. The "anthesis of male flowers - anthesis of female flowers" and "anthesis of female flowers – fruit setting" were the most stable interphase periods across the years both in the hybrids and in the parents. Eleven hybrids were classed as ultra-early, as their "emergence - ripening" period did not last longer than 63 days in 2022 or 72 days in 2021. On average in the hybrids across the study years, the variation amplitude (Am) of the "total yield" trait was 30.9 t/ha; of the “marketability” trait – 16%; of the "mean marketable fruit weight" trait – 2.9 kg. In the parents, Am was 43.1 t/ha, 20% and 2.8 kg for the ‘total yield’, ‘marketability” and "mean marketable fruit weight" traits, respectively. The variation limits (Lim) of the "yield" and "marketability" traits in the parents were wider than those in the hybrids. On the opposite, the variation limits of the "% to the check accession" and "mean marketable fruit weight" traits in the study years were wider in the hybrids. In breeding for yield, 10 F1 hybrids, which were significantly superior to the check F1 hybrid, ‘Kazka’, (130-166% to the check hybrid), are of practical value. Analysis of dominance and heterosis in the F1 hybrids allowed us to select the best combinations with the greatest dominance and heterosis for yield (hp=0.39-3.94; X=101-136), marketability (hp=0.11-7.00; X=101-106) and mean marketable fruit weight (hp=0.26-99.00; X=100-164). Based on high indicators of dominance and heterosis, 10 F1 hybrids were selected for further breeding; they were also noticeable for a set of economically valuable characteristics: early ripening, high yield, marketability, evenness, resistance to biotic factors, etc. Fruits of the selected hybrids are attractive in appearance and have excellent palatability. The selected F1 hybrids are valuable for breeding to create competitive first-generation watermelon hybrids. Conclusions. The interphase periods that were most stable across the years were determined. Eleven ultra-early hybrids were selected. Ten F1 hybrids, which in two study years were significantly superior to the check F1 hybrid, ‘Kazka’, (130-166% to the check hybrid), are of practical value. High marketability was noted in 6 hybrids. Analysis of dominance and heterosis in the F1 hybrids allowed us to select 10 combinations with the greatest dominance and heterosis for yield (hp=0.39-3.94; X=101-136), marketability (hp=0.11-7.00; X=101-106) and mean marketable fruit weight (hp=0.26-99.00; X=100-164) for further breeding, as they are of practical value for heterosis breeding.