Fruit Weight Research Articles

Evaluation of the Algerian Apricot Phenotypic and Genetic Diversity: Impact of Graft-Propagated Autochthonous and Introduced Cultivars in a Traditional Seed-Propagated System

AbstractDespite the apricot cultivars introduced from Spain and France are displacing the autochthonous Algerian cultivars in each area, there are a lot of local cultivars that still have a great interest and they are cultivated in the orchards from the Algerian arid agrosystem. This study addresses the phenotypical and molecular characterization of autochthonous (Algerian and Tunisian cultivars) and introduced (Spanish and French) graft-propagated apricot cultivars in a traditional seed-propagated system. Sixty-five apricot cultivated autochthonous and introduced accessions from the provinces of Batna (slightly arid area) and M’Sila (semi-arid area) in Algeria have been evaluated. These cultivated accessions included autochthonous Algerian cultivars (graft and seed propagated) selected over the years for its adaptation to warm Mediterranean climate and Spanish and French introduced cultivars (graft propagated). In these materials and agronomical evaluation of phenological (budburst, flowering and ripening date), pomological (fruit weight and yield per tree) and fruit quality (firmness and acidity), traits were performed together with a molecular characterization of the genetic diversity using simple sequence repeat (SSR) marks. Results showed the great diversity at agronomical and molecular level of this Algerian apricot germplasm. The seed-propagated autochthonous cultivars showed a lower yield per tree and fruit weight. Seed-propagated autochthonous also showed a longer fruit development and ripening cycle in comparison with the grafted cultivars with a later ripening date. Regarding fruit quality, seed-propagated autochthonous cultivars present low firmness and high acidity compared with the rest. Results also showed the effectiveness of the SSR markers by the correct identification, detecting some synonymies and suggesting the origin of some autochthonous cultivars. These results will provide more in-depth information to develop a strategy for in situ conservation of cultivars and to reduce gene flow from introduced material to ancient orchards. These materials would be interesting to modify some quality traits such as the acidity or firmness and drought resistance in apricot breeding programs.

Influence of Low Concentration of Paclobutrazol and Its Application Close to the Main Trunk on Fruiting of Mango in Ultra High Density Plantations

Control of flowering and fruiting in mango is achieved by the application of Paclobutrazol (PBZ) in many commercial orchards. However, growers tend to use very high concentrations of the chemical, resulting in high costs of operation and long-term effects. This study examines the impact of low concentrations and varying application methods of PBZ on mango fruit yield in ultra-high-density plantations. Here 3 methods of application and 4 levels of PBZ concentrations (PBZ 23% SC) were tried in a 3 year study. Application of PBZ at N1 (close to the trunk, also termed as collar drench), N2 (20 cm away from the trunk) and N3, (1 m away from the trunk), all resulted in similar number of fruits and fruit weights. Using very low concentrations of PBZ, 4 (0.37 g a.i. /m canopy diameter (cd), 5 (0.46 g a.i. /m cd) and 6 (0.55 g a.i. /m cd) ml/2 liter water, it was found that the lowest 0.37 g a.i. /m cd is enough to get statistically higher fruit yield. These findings: a very low dose of PBZ can result in high productivity and a requirement of least volume of the solution when applied as a collar drench would make the use of PBZ more sustainable and encourage more growers to adopt the hormonal use for mango production.

Genetic Variation in Yield and Fruit Weight Among Strawberry (Fragaria ×ananassa) Cultivars and the Interaction With Year and Location Effect

ABSTRACTStrawberry (Fragaria ×ananassa) is an important crop in the United States. In this study, we analysed strawberry trials established across 7 years and two locations. Our objective was to estimate genetic parameters and predict breeding values for yield. Linear mixed models were used for unbalanced data across years and locations and study the genotype by year and location interactions. The results suggested significant differences between cultivars for fruit weight but not for total and marketable yield. Fruit weight was controlled by genetic factors, shown by the high heritability of cultivar means (0.93), whereas marketable yield and total yield showed lower heritability estimates (0.48 and 0.63, respectively), indicating a substantial environmental influence. For fruit weight, cultivars exhibited stability across years and locations, supported by the high additive genetic correlations observed for cultivar‐by‐year (r = 0.90) and cultivar‐by‐location interactions (r = 0.98). Fruit weight and total yield were genetically independent as suggested near zero additive genetic correlation (−0.06 ± 0.416) between two traits, and they should be considered for an index selection in the strawberry breeding strategy.

Physiological, biochemical, and molecular characterization of some cucumber (Cucumis sativus L.) genotypes

ABSTRACT This study aimed to determine the morphological, pomological, biochemical contents, and molecular characterization of 11 cucumber genotypes of Egyptian origin and to reveal their molecular characterization. As a result it was determined that the highest fruit weight, the highest fruit length, and the highest fruit width were in the “Rahaf” genotype (respectively, 337.39 g, 23.25 cm, 53.97 mm). Biochemical analyses of the genotypes revealed that the highest total phenolic content was in the “Madayın” genotype (1938 mg gallic acid equivalent 100 g−1), the highest total antioxidant content was in the “C.5” genotype (59.25% inhibition), and the highest total flavonoid content was in the “Gazir” genotype (752.78 mg catechin equivalent 100 g−1). The highest Chlorophyll (a) content and Chlorophyll (a+b) was in the “Madayın” genotype (respectively, 4.33 mg g−1, 20.92 mg g−1), the highest Chlorophyll (b) content was in the “Iskay” genotype (6.59 mg g−1). It was determined that there were differences between genotypes in terms of other biochemical parameters examined. Using ten Inter Simple Sequence Repeat primers, 119 bands were obtained and the polymorphism rate was determined as 90.75%.

Effect of Organic Nutrients and Zinc Biofortification on Growth and Yield of Sponge Gourd (Luffa cylindrica L.) CV. Mahy Harita

A field experiment was carried out at Orchard, Department of Horticulture, Annamalai University, Faculty of Agriculture, TamilNadu during 2023-2024. The experiment was laid out in RBD with fifteen treatments in three replications. The organic manures used in the experiment were farm yard manure (25 t ha-1) and enriched manure (1 t ha-1) as soil application along with consortium biofertilizer (2 kg ha-1) and foliar application of biostimulants viz., panchagavya (3%), sea weed extract (3%) and effective microbial inoculants (2%). The zinc in the form of Bacillus subtilis @ 10 and 20g was applied as soil application. The results of the experiment revealed that the growth parameters viz., vine length, number of leaves, leaf length, leaf breadth and leaf area were recorded the highest in the treatment that received the application of farmyard manure 25 t ha-1combined with panchagavya (3%) as foliar application and Bacillus subtilis @ 20g. The yield attributes viz., the highest number of fruits plant-1, fruit length, fruit girth, fruit weight, fruit yield plant-1 and the zinc uptake in fruit were registered in the treatment which received the application of enriched manure @1 t ha1 combined with panchagavya (3%) as foliar application and Bacillus subtilis @ 20g (T11) respectively.

Effect of Seaweed Extract and Humic Acid Treatment on the Phenological and Yield Characteristics of Guava (Psidium guajava L.)

Aim: The main aim of this study was to evaluate the impact of seaweed and humic acid treatment at different doses on the phenological characteristics and yield of guava. Study Design: Randomized block design. Place and Duration of Study: A field experiment was conducted from December 2023 to July 2024 to assess the impact of bio-stimulants on the phenological and yield traits of guava (var. Arka Kiran) in the Poongunam village, Chengalpattu Dist, Tamil Nadu, India. Methodology: The experiment followed a Randomized Block Design with eight treatments: T₁ - Absolute control, T₂ - Water Spray, T₃ - 1% Seaweed Extract, T₄ - 1.5% Seaweed Extract, T₅ - 2% Seaweed Extract, T₆ - 1% Humic Acid, T₇ - 1.5% Humic Acid, and T₈ - 2% Humic Acid, each replicated three times. Results: Results showed that 2% Seaweed Extract (T₅) significantly improved flower retention (7.55 flowers per shoot), reduced the duration from flowering to fruit set (12.47 days), and shortened the time from fruit set to harvest (121.56 days). T₅ also led to the highest fruit set (68.65%), lowest fruit drop (48.72%), largest fruit weight (150.02 g), and greatest yield (13.35 kg/tree). Humic Acid at 2% (T₈) also improved fruit set (64.32%), fruit drop (49.54%), and yield (12.34 kg/tree), but was less effective than Seaweed Extract. Conclusion: This study demonstrates the potential of Seaweed Extract as a powerful bio-stimulant to enhance guava production, offering a sustainable alternative to traditional chemical treatments.

Microbial and organic manure fertilization alters rhizosphere bacteria and carotenoids of Citrus reticulata Blanco 'Orah'.

Citrus reticulata Blanco 'Orah' is one of the most widely grown citrus varieties in southern China. It has been proven that microbial and organic manure fertilization improve the yields and appearances of 'Orah' fruits. However, details regarding the mechanisms underlying the effects of combined fertilization on the agronomic traits and rhizosphere bacterial community of plants still need to be elucidated. This study compared the rhizosphere bacterial community and carotenoids of 'Orah' with (WYT group) and without (WYCK group) combined fertilization in a local orchard in Wuming town from Nanning, Guangxi, China. The WYT group was sprayed with 50ml Strongreen and 250g of Yumeiren five times while WYCK group did not sprayed. Combined fertilization increased fruit weight and the Citrus color index (CCI) significantly (p < 0.05). By 16s rRNA sequencing, 7,126 operational taxonomic units (OTU) were obtained. A higher Shannon index was observed in the WYT group compared to that in the WYCK group. Comparison between the two groups showed that Pseudomonas was enriched in the WYT group with LDA (log10) score of 4.32, and Cyanobacteria was enriched in the WYCK group with LDA (log10) score of -4.11. At the family level, Phyllobacteriaceae (abundance mean: 0.0046 in WYCK vs. 0.0073 in WYT) was significantly abundant in the WYT group, whereas Thermosporothrix (abundance mean: 0.00053 in WYCK vs. 0.0019 in WYT) and Sphingobium (abundance mean: 0.00053 in WYCK vs. 0.0013 in WYT) were significantly abundant in the WYCK group. A total of 51 carotenoid components were tested by UPLC-MS/MS. In the pulp tissues, 37 carotenoid components were decreased in the WYT group compared to those in the WYCK group. In fruit skin, 24 significantly different components (7 downregulated and 17 upregulated) were identified in WYT compared to those in WYCK. Correlation analysis revealed that the network between OTUs and carotenoids contained seven carotenoid components and four OTUs. Four OTUs, strain TRA3-20 (a eubacterium), Roseiflexus, OPB35, and Fictibacillus correlated to carotenoid accumulation regulation in fruit skin. This study demonstrates the impact of the fertilization on soil microorganisms and carotenoid components. It constructs the regulatory network contained four OTUs for seven carotenoid components, providing evidence on precise fertilization in Orah.

Estimation of genetic polymorphism in quince (Cydonia oblonga Mill.) genotypes using morphological traits and molecular (DNA barcoding) characterizations.

Quince (Cydonia oblonga) is a medicinal plant and a member of family Rosaceae. It is native plant of Asia Minor and Europe. It is used in production of jam and jellies and also as a remedy of several ailments. The present study was conducted to evaluate the genetic polymorphism based on morphological and molecular traits. Different varieties of Quince were collected from different ecological zones of Khyber Pakhtunkhwa Pakistan and a total of 26 different morphological traits were recorded among studied genotypes. Based on qualitative morphological trait study, the variety collected from Tindodag was unique one with highest fruit weight (328.82 g). The lowest fruit weight (68.38 g) was recorded for Talash genotype. The Charbagh and Tindodag genotypes showed highest seed length (10.6 mm) while genotypes of Chitral was recorded as lowest (8.4 mm). Statistically, significant level of variation was noted with coefficient of variance ranged from 2.23% to 30.38%. Based on correlation analysis, fruit length had strongly correlation with fruit weight (r = 0.89**), Average Fruit width was found significant with fruit weight (r = 0.90**). Similarly, the Core Width was found strongly significant with Core Length (r = 0.95**). ANOVA analysis indicated 10 quantitative characters to be highly significant, 2 significant and 1 insignificant. Principal component analysis was also computed for the 13 quantitative traits with Eigen value of 0.48 and a total variance of 97.78%. The first principal component shows total variation of 52.52%. In PC2 the total variation was 80.15%, PC3 94.06% while in PC4 it was 97.78%. The NCBI BLAST results shows that all the genotypes have similar origin except Tindodag genotype, which shows differences in its origin. Accession number for all other genotypes is MN216014.1, while accession number of Tindodag genotype is KF861967.1. Based on this study, it can be concluded that Tindodag genotype is unique out of the studied localities. NCBI BLAST have provided further support for the drawn conclusion.

Releasing a sugar brake generates sweeter tomato without yield penalty.

In tomato, sugar content is highly correlated with consumer preferences, with most consumers preferring sweeter fruit1-4. However, the sugar content of commercial varieties is generally low, as it is inversely correlated with fruit size, and growers prioritize yield over flavour quality5-7. Here we identified two genes,tomato(Solanum lycopersicum) calcium-dependent protein kinase 27 (SlCDPK27; also known as SlCPK27) and its paralogue SlCDPK26, that control fruit sugar content. They act as sugar brakes by phosphorylating a sucrose synthase, which promotes degradationof the sucrose synthase. Gene-edited SlCDPK27 and SlCDPK26 knockouts increased glucose and fructose contents by up to 30%, enhancing perceived sweetness without fruit weight or yield penalty. Although there are fewer, lighter seeds in the mutants, they exhibit normal germination. Together, these findings provide insight into the regulatory mechanisms controlling fruit sugar accumulation in tomato and offer opportunities to increase sugar content in large-fruited cultivars without sacrificing size and yield.

Efficacy of soil drench and foliar application of iron nanoparticles on the growth and physiology of Solanum lycopersicum L. exposed to cadmium stress.

Cadmium (Cd) can harm the yield and quality of vegetables, threatening food safety. Essential microelements such as iron are crucial for plant growth and can help alleviate heavy metal stress. Recently, nanoparticles have been studied as eco-friendly solutions for mitigating heavy metal stress in plants. In the present study, iron nanoparticles (FeNPs) at 0, 100, and 300mg/L were applied as soil drenches and foliar sprays to tomato plants under cadmium stress. A comparison was made between the application methods of FeNPs by evaluating the growth parameters of tomato plants, including shoot length (SL), root length (RL), number of branches (NB), number of leaves per plant (NL), and leaf area (LA), as well as by assessing biochemical and antioxidant enzyme parameters. In the Cd stress treatment, the protein content decreased by 24.71%, and the phenolic and flavonoid content of the tomato plants also decreased due to cadmium stress, with levels decreasing from 16.07 to 6.9µg and from 0.36 to 0.16µg, respectively. Compared with the soil drench, 100mg/L FeNPs significantly improved the parameters of Cd-stressed plants when used as a foliar spray, leading to increases in shoot length, root length, fruit weight, number of fruits, number of leaves, and number of branches by 42%, 66%, 24%, 66%, 173%, and 45%, respectively. Tomato plants treated with this spray presented increased carotenoid and lycopene contents. FeNP foliar spray also reduced Cd accumulation in plant tissues. This technique shows promise in alleviating Cd stress in vulnerable vegetable plants such as tomatoes.

Comparison of the Morphological Characteristics, Yield, and Quality Traits of Fruits of Two Papaya Cultivars Grown Under Protected Cultivation

This study aimed to investigate the morphological characteristics and performance of Formosa and Sunrise Solo papaya cultivars under protected cultivation in subtropical climate conditions as well as the relationships between the yield and factors affecting the yield. The Formosa cultivars had higher values in terms of plant height (519.4 cm), stem diameter (238.4 mm), first flowering height (138.2 cm), and duration from flowering to harvest (141 days) compared to the Sunrise Solo cultivars. The yield per plant was higher in the Formosa cultivars (52.5 kg/plant/year) than in the Sunrise Solo cultivars (27.4 kg/plant/year). The values of fruit peel color parameters were highest in the spring, the fruit flesh firmness was highest in the autumn, and the soluble solid content was higher in fruits harvested in the summer. Medium to high positive phenotypic correlations were found between the first flowering height and fruit set, fruit weight, yield, fruit width, fruit length, and fruit flesh firmness (0.371–0.595) and between the fruit set (number/plant) and fruit weight, yield, fruit width, fruit length, and fruit flesh firmness (0.388–0.819) (p ≤ 0.01). The papaya can be commercially cultivated under protected cultivation in extreme subtropical conditions, and the Formosa cultivars generally performed better than the Sunrise Solo cultivars across many parameters.

Changes in total soluble solids concentration, fruit acidity, and yeast assimilable nitrogen in response to altered leaf area to fruit weight ratio in Pinot noir

The increasing consumer demand for lower alcohol wine and the need to mitigate against a warming climate presents new challenges for winegrowers and the desire to produce grapes with lower total soluble solids (sugar) or earlier harvesting, while preserving other wine compounds and attributes, particularly for varieties intended for red wine production. We investigated how reducing vine leaf area through shoot trimming and leaf removal, applied at different severities and timings to modify the leaf area to fruit weight (LA) ratio, affects fruit composition for producing lower alcohol quality Pinot noir wine. Shoot trimming treatments (half canopy, H in 2015/16 and 2016/17, and quarter canopy, Q in 2016/17 by alternately removing leaves after trimming shoots to half) were applied shortly before veraison (V-, E-L 34), during veraison (V, E-L 35) and post-veraison (V+, E-L 36) in three different vineyard locations (Marlborough, Canterbury and Central Otago, New Zealand). Untrimmed vines served as the control. Lateral shoots were removed during treatment application, and regrowth was removed to maintain a consistent leaf area. Results showed that reducing the LA:FW ratio delayed the accumulation and concentration of total soluble solids (reduction of 1.0 to 2.7 °Brix) at harvest in all trimmed vines over both seasons. Berry weight, malic acid concentration, titratable acidity, and pH at harvest were unaffected by trimming. At target TSS levels of 18 °Brix (10 % ethanol, v/v) in the Marlborough vineyard and 20 °Brix (11 % v/v) in the Central Otago vineyard, V+ vines showed malic acid and titratable acidity levels comparable to the control. At the Canterbury vineyard, these parameters remained similar across all treatments at 16 °Brix (8.9 % v/v). Yeast-assimilable nitrogen concentration increased (188 to 411 mg/L) in early trimmed vines. At Central Otago, roots showed lower carbohydrate reserves across all trimming treatments, likely due to the high yield at the site, while at Canterbury, trimming did not result in significant differences in carbohydrate reserves, likely due to the low yield at the site. At the Marlborough vineyard, vines trimmed early and more severely had less starch in their roots, while HV+ vines maintained similar levels of starch to controls. In conclusion, halving the canopy post-veraison (HV+, LA 0.70 m²/kg as observed in Marlborough) could be considered a viable viticultural option to lower sugar accumulation, thereby reducing potential alcohol content, without affecting titratable acidity and pH. This practice offers significant potential for adapting to a warming climate and producing lower alcohol Pinot noir wines in a sustainable manner.

Effect of fertigation scheduling and doses of NPK on growth, yield and quality of cherry tomato (Solanum lycopersicum L. var. cerasiforme) under protected condition

This study investigated the impact of different fertigation schedules on cherry tomato (Solanum lycopersicum var. cerasiforme) cultivation in a controlled environment at TNAU, Coimbatore, India. A Completely Randomized Design with nine treatments and three replications was used, incorporating various combinations of soil application and fertigation with water-soluble fertilizers at 25%, 50%, 75%, and 100% of the recommended dose of fertilizer (RDF). Critical parameters such as growth, phenological traits, yield, fruit quality, soil nutrient status, and plant nutrient uptake were evaluated. Statistical analyses, including ANOVA, path coefficient analysis, and principal component analysis (PCA), were performed to assess treatment effects and identify relationships between variables. The results consistently demonstrated that fertigation with water-soluble fertilizers at 100% RDF (T3) yielded the best outcomes for most parameters, followed by 75% RDF fertigation (T4) and a combination of 25% soil application and 75% fertigation (T7). Significant improvements in plant growth, yield and fruit quality were observed with optimized fertigation compared to traditional soil application methods. T3 (100% RDF through fertigation) resulted in the highest plant height (263.95 cm), number of primary branches (15), leaf area (316.77 cm²) and dry matter production (96.85 kg/plant). Yield attributes such as fruits per plant (326.50), fruit weight (3.73 g), and total yield (23.95 t/ha) were also highest in T3. Path coefficient analysis indicated strong positive correlations between growth and yield parameters. PCA showed that the first principal component accounted for 85.9 % of the total variation. These findings highlight the potential for fertigation to improve resource use efficiency and productivity in cherry tomato cultivation.

Strategic honey bee hive placement improves honey bee visitation but not pollination in northern highbush blueberry.

Commercial blueberry Vaccinium spp. (Ericales: Ericaceae) production relies on insect-mediated pollination. Pollination is mostly provided by rented honey bees, Apis mellifera L. (Hymenoptera: Apidae), but blueberry crop yields can be limited due to pollination deficits. Various hive placement strategies have been recommended to mitigate pollination shortfalls, but the effect of hive placement has received limited formal investigation. This study explores the effects of clumped and dispersed hive placement strategies on honey bee visitation and pollination outcomes in "Bluecrop" and "Duke" fields over 2 years (2021 and 2022) within 2 economically important regions of production in the United States-the Midwest (Michigan) and Pacific Northwest (Oregon and Washington). Clumping hives consistently increased honey bee visitation rate but did not result in higher fruit set, fruit weight, or seed count. Increases in honey bee visitation through clumping could perhaps improve pollination outcomes in more pollination-limited blueberry cultivars and other pollination-dependent crops. Clumping hives is substantially more efficient and cost-effective for beekeepers due to fewer drop locations and could lead to cost savings for both beekeepers and blueberry growers without growers sacrificing pollination levels and crop yields.

Calcium Silicate Application as a Salt Stress Mitigation Strategy for Vegetables in the Salt-affected Soils of Sandy Plains of Kerala, India

Soil salinity inhibits plant growth due to osmotic stress and reduced plant and water uptake. In the Onattukara sandy plains of Kerala, saltwater intrusion is a major problem in several panchayaths near the coastal area. In uplands also, cultivation is not possible due to the salt stress from saltwater intrusion. One of the strategies for removing the inhibitory effect of salt stress on plant growth is the application of beneficial nutrients to the plants. Therefore, a study was carried out to understand the effect of calcium silicate application on mitigating salt stress in vegetables and using tomato as a test crop. A detailed germination study was conducted in laboratory conditions prior to pot culture experiment to find out the critical level of salinity for tomato and two salinity levels 30mM and 40 mM NaCl were selected for the pot culture experiment. For accessing the effect of the various levels of calcium silicate on reducing salt stress in tomato, a pot culture experiment was conducted in Onattukara region (AEU 3) in completely randomized design with ten treatments replicated thrice with varying levels of CaSiO3 from 100 kg ha-1 to 150 kg ha-1. The treatments had a significant effect on all the biometric characteristics and yield attributes of the crop. The highest fruit weight, fruit per plant, and fruit yield were observed in treatment with soil test-based NPK recommendation and 125 kg ha-1 of CaSiO3 applied. It was also observed that the relative water content was higher and the water saturation deficit was lower in this treatment. CaSiO3 application @125 kg ha-1 along with soil test-based recommendation of NPK can be recommended as a salt stress mitigation strategy for boosting vegetable production in the salt-affected soils of sandy plains of Kerala.

Phenotypic Trait Analysis of Tomato (Solanum lysopersicum) Genotypes in Qatar and Indian Agro-climatic Conditions

Background: The study included four genotypes of tomato (EC620378, EC620380, EC620383, EC620534) which were cultivated to find out their similarities and differences based on phenotypic traits when they were grown under different soil zones of Doha (Qatar) and Meerut (India) to find out that which of the genotypes can be cultivated better in Qatar and India. Methods: The experiment was laid out in Randomized Complete Block Design (RBCD) with two replications. Statistical analysis for variation in quantitative characteristics among genotypes was done by collecting data in 15 qualitative and quantitative traits. Data showed great variation for almost all the traits. The principal component analysis involved plant height and days to marketable maturity as the most discriminating trait that accounted for greater variability in genotypes in both zones, and they should be considered in tomato improvement programs. The correlation analysis showed that fruit yield per plant was positively and significantly correlated with number of fruits per plant and fruit width. Present findings suggest that the identified superior genotypes may be utilized by different farms to further improve their breeding and cultivation strategies. Result: In Indian soil zone, genotype EC620534 performed extremely well in terms of maximum yield per plant. Similarly, in Qatar soil zone, EC620534 and EC620380 performed well. The phenotypic coefficient of variation (PCV) was higher than its corresponding genotypic counterpart (GCV) for all characters studied showing environmental influence. High broad-sense heritability were recorded for days to marketable maturity, fruit shape index and fruit weight in both agro-climatic zones, they were associated with low genetic advance indicating non-additive gene action and environmental influence, hence, heterosis breeding is recommended.

Estimation of genetic variability parameters and trait association in cherry tomato (Solanum lycopersicum L. var. cerasiforme)

Cherry tomatoes are the smaller version of classic tomatoes but are valued for their sweet taste and captivating colors. They are highly favored by the urban elite and the chefs catering to high-profile restaurants. To formulate selection criteria for utilization in breeding programs, variability parameters, an association between different characters, and direct and indirect effects of component traits of 29 cherry tomato genotypes were assessed under polyhouse conditions. Sufficient genetic variability was found for the morphological and yield traits studied, as revealed by the variance analysis. Plant height, primary branches per plant, days to 50 percent flowering, flower clusters per plant, flowers per cluster, fruits per cluster, days to first harvest, fruits per plant, fruit length, fruit girth, fruit weight, locules per fruit, pericarp thickness, days to final harvest, yield per plant, total soluble solids, lycopene, ascorbic acid, reducing sugars and non-reducing sugars showed high estimates of heritability and genetic advance as percent of the mean. Correlation analysis demonstrated a significant positive relationship between fruit yield per plant and pericarp thickness (0.727), fruit length (0.685), fruit girth (0.536), fruit weight (0.530), and the number of fruits per cluster (0.386). Principal component analysis identified the primary component (PC1) as the main contributor to variance. Path analysis revealed that fruit length, pericarp thickness, number of fruits per plant, flowers per cluster, and fruit weight had the highest direct effect on yield. These traits were the key factors influencing fruit yield per plant in cherry tomatoes.

Evaluation of F2 Segregating Population of Chilli (Capsicum annuum L.) for Yield and Leaf Curl Virus Resistance

Chilli (Capsicum annuum L.) is an important vegetable crop, cultivated worldwide for its fruits which are valued for pungency, flavor, and nutritional benefits. However, chilli production is significantly restricted by various biotic stresses, especially the Chilli leaf curl virus (CLCV). The present study was conducted at the Department of Vegetable Science, College of Agriculture, Vellayani, Kerala Agricultural University during 2020-2021 to evaluate the F2 segregating population of chilli crosses viz., CHIVAR-6 x Sel-4 and CHIVAR-10 x Sel-3 for yield and leaf curl virus resistance. Evaluation of vegetative and yield related traits was conducted on these populations under the field conditions. Significant variability was observed for various traits such as plant height, fruits per plant, fruit length, yield per plant and resistance to leaf curl virus. The scoring for chilli leaf curl virus was done and based on the scoring the segregants were categorized into highly resistant, resistant, moderately resistant, moderately susceptible, susceptible and highly susceptible. Among the F2 population of the first cross, fruits per plant, plant height, fruit weight and fruit girth showed high and positive correlation with yield per plant. The segregants of the second cross recorded significant positive correlation for fruits per plant, plant height and fruit length with yield. The results of the study provide valuable insights into breeding for both high yield and leaf curl virus resistance, crucial for enhancing chilli production under the challenging situations.

Breeding of new kiwifruit (Actinidia chinensis) cultivars with yellow (golden) fleshed and superior characteristics

The most widely cultivated species globally is Actinidia deliciosa cv. ‘Hayward’. However, in recent years, consumers have shown greater demand for new varieties with novel flesh colour, flavour and appearance in international markets. To meet these expectations, one breeding study was started in 2016 at the University of Guilan in Iran to develop new kiwifruit cultivars with superior characteristics. In this breeding program, 201 female and 534 male hybrid genotypes were obtained from combinations of six different parents using the controlled cross-breeding technique. The evaluations were carried out over three consecutive stages. In the first stage, 201 female hybrid genotypes and control (‘Golden’) were evaluated based on 25 phenological and pomological traits. In the second stage, hybrids passed the desired threshold values in 7 key attributes were selected. Sensory testing in the next stage evaluated these selected hybrid genotypes more. As a result of the first stage, 30 hybrid genotypes with fruit weight (90 ≥ g) were selected. Then, in the second stage, 21 hybrids that showed acceptable dry matter, hue angle, flesh firmness, soluble solid content, acidity, and ascorbic acid were selected. Finally, 13 hybrid genotypes received high scores in sensory testing, and just two hybrid genotypes represented a 100% of novelty with positive texture. These genotypes were selected as potential cultivar candidates. In future studies, fruit yield, disease/pest resistance, and post-harvest performance trials of the 13 selected candidates will be evaluated at different sites. Thus, the ones that give the best results will be introduced to kiwifruit growers.

Exploring Genomic Regions Associated with Fruit Traits in Pepper: Insights from Multiple GWAS Models.

This study utilized 303 pepper accessions from diverse Capsicum species to explore fruit traits, including length, width, wall thickness, and weight. Descriptive statistics revealed a mean fruit length of 66.19 mm, width of 23.48 mm, wall thickness of 1.89 mm, and weight of 15.29 g, with significant variability, particularly in fruit weight. Correlation analysis demonstrated strong positive relationships between fruit width, weight, and fruit wall thickness (r = 0.89 and r = 0.86, respectively), while fruit length showed weaker correlations with these traits. Analysis of fruit positions revealed that the majority of accessions had a pendent fruit position (156), followed by erect (85) and intermediate (8). In terms of fruit shape, triangular and narrow triangular shapes were the most common, observed in 102 and 98 accessions, respectively. Genome-wide association studies (GWAS) identified significant single nucleotide polymorphisms (SNPs) associated with fruit traits across four models (Blink, FarmCPU, MLM, MLMM). The number of significantly associated SNPs were as follows: fruit length (89), fruit width (55), fruit weight (63), fruit wall thickness (48), fruit shape (151), and fruit position (51). Several genes were also identified where the SNPs are located or adjacent to, providing candidate genes for further exploration of the genetic basis of fruit morphology. Notably, genes such as E3 ubiquitin-protein ligase RGLG1 (associated with fruit width), Homeobox-leucine zipper protein HDG11 (involved in fruit width), Auxin response factor 23 (linked to fruit shape), and ATP-dependent zinc metalloprotease FtsH (related to fruit weight) were identified. These findings enhance our understanding of the genetic basis of fruit morphology in Capsicum, offering valuable insights for breeding and agricultural practices.