Fruit Shape Index Research Articles

Selection of Fertilizer and Cultivar of Sweet Pepper and Eggplant for Hydroponic Production

Dutch bucket hydroponic trials were conducted with the aim to evaluate the effects of different hydroponic fertilizers (5N-4.8P-21.6K, 5N-5.2P-21.6K, and 7N-3.9P-4.1K) on growth, fruit production, and the fruit quality (fruit shape index) parameters of two cultivars of sweet pepper (Capsicum annuum L.) and on two cultivars of eggplant (Solanum melongena L.). For sweet pepper yield, the 5N-4.8P-21.6K fertilizer was responsible for the greatest yield for both cultivars. For sweet pepper fresh and dry shoot weight interaction, the ‘Orangella’ cultivar had greater growth in 5N-4.8P-21.6K and 5N-5.2P-21.6K fertilizers, whereas there was no difference among cultivars in 7N-3.9P-4.1K. Shape index was not affected by fertilizers or cultivars. For the eggplant yield, there was no main effect nor interaction between fertilizers and cultivars for fruit yield, while the interaction between fertilizers and cultivars was significant for shoot fresh weight production. Shoot fresh weight was greater for ‘Angela’ than ‘Jaylo’ in 5N-4.8P-21.6K and 7N-3.9P-4.1K. Furthermore, both eggplant cultivars were affected with yellowing of fruits in all fertilizer treatments after 2 months, which was probably due to the accumulation of nutrients in the closed hydroponic system. Therefore, hydroponic producers could select 5N-4.8P-21.6K and 5N-5.2P-21.6K fertilizers for the cultivation of the ‘Orangella’ cultivar of sweet pepper based on yield. It is important to evaluate more fertilizers and cultivars for eggplant hydroponic cultivation.

Effects of quince pollen pollination on fruit qualities and phenolic substance contents of apples

In the apple industry, the improvement of apple fruit aroma and polyphenol content has always been an important goal of breeding. In this study, pollination experiments of ‘Yan 3 Fuji’, ‘Indo’ and ‘Ryokano kisetsu’ apples were carried out by using pollen grains of quince (Cydonia oblonga Mill.). The results indicated that single fruit weight, fruit firmness, vitamin C content, sugar-acid ratio, total phenolics and total flavonoids were significantly affected by quince pollen, while quince pollen had no significant effect on fruit shape index, titration acid and total anthocyanins. In addition, valuable phenolic compounds, including catechin, epicatechin, chlorogenic acid, phloridzin, quercetin, and quercetin 3-D-galactoside, were significantly influenced by quince pollen. Moreover, esters such as acetic acid pentyl ester, acetic acid hexyl ester, butanoic acid hexyl ester, butanoic acid-2-methyl- hexyl ester and hexanoic acid hexyl ester in three kinds of apple were all increased after pollination by quince. Obvious metaxenia was observed between quince pollen and apple.

HETEROSIS AND COMBINING ABILITY FOR SOME FRUIT QUALITY TRAITS OF EGYPTIAN MELON INBRED LINES USING LINE × TESTER ANALYSIS

this study was carried out during the period from 2016 to 2018 summer seasons in the open field at Kaha Vegetable Research Farm (KVRF), Kalubia, Egypt. Thirty local inbred lines of melon (Cucumis melo var. ananas) were evaluated in this investigation during 2016 and 2017 summer seasons in the open field to determine their mean performance. Based on the former evaluation, 12 inbred lines (RIL A2, RIL A3, RIL A7, RIL A8, RIL A14, RIL A18, RIL A19, RIL A22, RIL A23, RIL A26, RIL A29, RIL A30) and 3 testers (RIL A5, RIL A10 and RIL A20) were selected to determine their genetic performance using line × tester mating design during 2018 summer season. Thirty six crosses in one direction were conducted in the plastic house of Kaha Vegetable Research Farm, Kalubia through the 2017 late summer season. The 36 hybrids were evaluated along with their parents to determine heterosis, combining ability and heritability of leaf area index (LAI), yield components, average fruit weight, netting percentage, fruit shape index (FSI), seed cavity diameter, flesh thickness and total soluble solids (TSS). The genotype results showed highly significant mean squares for most of the studied traits. Inbred lines (female parents), Testers (male parents) and Line x Tester interaction showed highly significant differences of almost whole traits. Some crosses revealed highly significant and significant mid-parent and better-parent heterosis for many of the traits. The inbred line RIL A5 (T5) showed higher positive general combining ability (GCA) impact for all traits except early yield and FSI, which could be used as parent in breeding programs and the potential parent (good combiner) that in selection program would be effective for its efficient use in subsequent crossing programs for more LAI, total yield, marketable yield percentage, average fruit weight, netting percentage, flesh thickness, TSS and less seed cavity diameter. Nine, eight, twelve and seven hybrids revealed highly significant and significant specific combining ability (SCA) impacts ofearly yield, total yield, average fruit weight and TSS, respectively. The best specific combining ability (SCA) was observed in hybrids RIL A29 × RIL A5 for early yield, RIL A19 × RIL A20 for total yield and RIL A8 × RIL A10 for average fruit weight and TSS. The results confirmed the presence of genetic differences among the genotypes (female and male parents) and heterosis of crosses indicating the existence of predominance of nonadditive gene action in genetic control of the studied traits.

CHANGES IN PHYSICAL AND CHEMICAL PROPERTIES OF CORNELIAN CHERRY (CORNUS MAS L.) FRUITS IN DEPENDENCE ON DEGREE OF RIPENING AND ECOTYPES

Cornelian cherry in Poland belongs to the alternative fruit species. The fruits are suitable for fresh consumption, however they can be used for processing: juice, jams, jellies, syrups, tinctures. Fruits are abundant in mineral elements, vitamin C, organic acids, iridoids, anthocyanins and due to that they have health-promoting significance. In this experiment, the fruit quality of several 16-year-old ecotypes in the Lublin region was compared. They were compared in terms of the beginning of fruit ripening and fruit size (length, diameter, mass), fruit shape index, share of stone in the fruit, SSC, TA, SSC/TA, reducing sugar, dry matter content and anthocyanins content. The color of fruit was evaluated in two dates, visually and using HanterLab spectrophotometer. Cornelian cherry fruits began to mature at the beginning of August and at the latest at the end of August. With the increase of the maturity degree, the SSC, reducing sugars, TA, dry matter and anthocyanins increased significantly. There was no difference in the taste of light red fruits and dark red fruits, which were characterized by similar ratio of SSC/TA. Ecotype No. 11, as the earliest maturing, with big round fruits, dark red colored with the highest content of anthocyanins, could be distinguished. As well as ecotypes No. 4 and 5, ripening in mid-August, and having a high ratio of SSC/TA, providing a good taste. Studied ecotypes could be used in breeding programs to incorporate a wide range of quality and agronomic characteristics into a final cornelian cherry cultivar.

Potential for domestication of Borassus aethiopum Mart., a wild multipurpose palm species in Sub-Saharan Africa

Borassus aethiopum Mart. is a multipurpose palm native to mainland Africa. Fruits and hypocotyls are the most exploited parts which collection/harvest threats the species. As a pre-requisite for its domestication, this study assessed the (1) environmental-induced diversity in morphological traits of fruits and (2) differences in growth and weight of hypocotyls from one-seeded, two-seeded, and three-seeded fruits from three provenances in the three climatic regions of Benin. 5400 fruits collected from 180 trees in six populations were measured for fruits and tree morphological traits. A randomized complete block design with three replicates was used for the experimentation in each region. Variation in fruit morphological traits was not influenced by climatic regions. The greatest variation (65–94%) in fruit morphological traits was located at tree level, highlighting that selection of many fruits and individual trees within a few populations would capture large variation of fruit traits. Tree diameter at breast height (18.5–52 cm), total (6.4–19.6 m) and bole (4.8–17.6 m) height, and fruit length (7.00–20.50 cm), dry weight (98–2552 g), shape index (0.59–2.80), and number of seed (1–3) were the most discriminative traits of studied populations. Clustering of the trees resulted into five morphotypes based on discriminating traits. Morphotypes 1 and 2 showed high performances for fruits and seeds production. These morphotypes are good candidates for selection and breeding programs. Irrespective of the provenances, best performances of hypocotyls were observed in the humid region. This study provides important baseline information for the domestication of B. aethiopum.

Genetic studies of yield and its component traits using generation mean analysis in summer squash (Cucurbita pepo subsp. pepo)

The present investigation involved the generation mean analysis of six generations (P1, P2, F1, F2, BC1P1 (F1 × PCK-1) and BC1P2 (F1× Lady Godiva) derived from cross of PCK- 1(hulled seed) × Lady Godiva (hull-less seed) in summer squash. The pooled analysis of variances revealed highly significant differences among the generation means of different populations for vine length (cm), leaf length (cm), days to 50% flowering, inter-nodal length (cm), peduncle length (cm), polar diameter (cm), equatorial diameter (cm), flesh thickness (cm), fruit yield per plant (kg), number of seeds per fruit and seed yield per fruit (g).The epistasis was absent for node number of 1st female flower, node number of 1st male flower, number of primary branches, leaf width (cm), days to 1st harvest, number of fruits per plant, average fruit weight (kg), fruit shape index and petiole length (cm), where leaf width, number of fruits per plant, and petiole length with highly significant additive genetic variances and partial dominance can be improved through inbreeding and selection. However, over-dominance in the inheritance of node number to first female flower, node number to first male flower, number of primary branches per vine, days to 1st harvest, average fruit weight and fruit shape index suggested use of heterosis breeding for improvement. Six parameter model unveiled the preponderance of dominance and dominant × dominant [l] gene interactions for most of the other traits with the inheritance of many dominant genes carrying small and cumulative effects. However, the opposite effects of dominance [h] and the estimates of dominant × dominant [l] interactions highlighted duplicate type of geneinteractions. Therefore, summer squash cross involving PCK-1(hulled seed) × Lady Godiva (hull-less seed) can be used as a source of dominant genes and inter-allelic gene combinations for the expression of yield and related traits that can be exploited in the form of hybrid vigour through heterosis breeding.

Genetic variability studies in tomato (Solanum lycopersicum L.) under ecofriendly management

Twenty genotypes of tomato were evaluated for yield, quality and other traits under eco-friendly management. Analysis of variance revealed that highly significant differences among genotypes for all the traits. High magnitude of phenotypic coefficients of variation and genotypic coefficients of variation were observed for traits including fruit yield per plant, plant height and number of fruits per plant. High heritability coupled with high genetic advance estimates were observed for number of fruits perplant, plant height and fruit yield per plant. Fruit yield/planthad positive and highly significant correlation with number of fruits/ plant, fruit weight, fruit shape index and number of primary branches/plant indicating these traits are important yield components. Whereas, negative andsignificant association with days to 50% flowering, leaf curl and fruit borer incidence, ascorbic acid content and thickness. Maximum positive and direct effect towards fruit yield/plant was exerted by average fruit weight, number of fruits per plant, leaf curl incidence and plant height. Few genotypes with high yield and other useful traits were identified for future under eco-friendly management.

Heterosis and Combining Ability for Development of Squash Hybrids (Cucurbita pepo L.)

The aim of this study is to evaluate a set of inbred lines and their hybrids and to determinate the phenotypic and genotypic parameters. In addition, identify the heterosis and combining ability for the studied traits in order to determine the best combinations and the ideal improvement strategy for hybrid production in squash. The experimental study was conducted at El-Baramoon Research Station, Horticulture Research Institute during the two summer season of 2016 and 2017. Six inbred lines selected from Eskandrani cultivar and fifteen F1 hybrids were evaluated for different traits. Significant differences were observed among the hybrids and their parents for all studied traits. Based on mid-parent heterosis, the hybrid (P5 x P6) gave the highest value for early yield per plant (98.51 %) followed by the hybrid (P1 x P4) (90.24%) for the same trait. While heterosis over better parent, the hybrid (P1 x P6) gave the highest value for early yield per plant (78.95 %) followed by the hybrid (P5 x P6) (73.91 %) for the same trait. Furthermore, the highest mid-parent hertrosis for total yield per plant was obtained by the hybrid P4 x P6 (75.0%) followed by P5 x P6 (60.38%) and P4 x P5 (59.65%). Otherwise, the largest heterosis over better parent for total yield per plant were expressed by P4 x P6(61.77%) followed by P4 x P5 (46.77%) and P5 x P6 (37.10%), respectively. General combining ability (GCA) was significant or highly significant for all traits except for early yield per plant and shape index, specific combining ability was highly significant for all traits except for number of node female flower and early yield per plant. The estimated GCA/SCA mean squares revealed that the additive gene effects were the major effect in the inheritance of all studied traits, except for early yield per plant and vitamin C. Also, GCA estimates were larger than their corresponding estimates of SCA for most of the studied traits. The result illustrated that both additive and non-additive gene actions were positive for all studied traits. Heritability in broad sense ranged from 72.95 to 99.46 % for number of node female flower and total soluble solids, respectively. Also, heritability in narrow sense ranged from 28.49 to 81.94 % for number of leaves per plant and fruit shape index. The parent P1, P2 and P3 could be recommended as good combiners for average fruit weight, vitamin C, number of fruits per plant and total yield per plant whereas the P5 and P6 as promising parents for plant height, leaf area, number of leaves per plant , days to anthesis of female flowers, number of node of female flower and total soluble solids.

Influence of Compost, Boron and Potassium on some Traits in Cucumber (Cucumis sativus L.) Grown in Alluvial Soil

Cucumber (Cucumis sativus L.) is among the most important vegetable crops grown in Egypt for local consumption and exportation. The purpose of this investigation was to evaluate the effect of two compost types (plant residues and animal residues) with foliar spraying of potassium and boron elements on improving the fruit yield and quality of the cucumber plants grown in an alluvial soil during the two successive summer seasons of 2015 and 2016. The experimental design was a split plot design with three replicates for each treatment. The compost treatments were (C1): Animal compost was applied at rate of 0.2 m3 plot-1 and (C2): compost of rice straw (CRS) was applied at rate of 0.2 m3 plot-1 .While the foliar treatments were (T1): B was foliar applied as boric acid at rate of 0.44 mg L-1, (T2): K was foliar applied as potassium acetate at rate of 200 mg L-1 and (T3): combination of B and K was foliar applied at the same rates as mentioned above. The results showed that, the highest values of all studied vegetative growth parameter such as fresh and dry weights (g plant-1), stem length and diameter(cm) of cucumber plant in both studied seasons were achieved at (C2 (Plant compost) × T3 (B+K)) treatment, while the lowest values were obtained at control treatment (without compost or foliar application).Also, fruit characteristics such as [average fruit weight (g), fruit diameter and length (cm), fruit shape index (LD-1)] and yield [early, total yield (kg plot-1) and total yield (ton fed-1)] gave the same trend in both studied seasons. Also, the values of nitrogen, phosphorus, potassium and boron contents in leaves of cucumber plant were evaluated under the effect of different types of compost and foliar application of B and K at the same time.

The evaluation of lipids raw material resources with the fatty acid profile and morphological characteristics of Idesia polycarpa Maxim. var. vestita Diels fruit in harvesting

Idesia polycarpa Maxim. var. vestita Diels (further referred as I. polycarpa), belonging to Salicaceae family, is a perennial woody plant. I. polycarpa seed and fruit are well known to be rich in oils, what’s more it is considered to be an industrially valuable oilseed plant grown in the subtropical and temperate regions. The aim of this paper is to systematically study the lipid content, fatty acid profile of oil and morphological characteristics of the I. polycarpa fruit collected from various regions in China. The degree of the changes in oil content and fatty acid composition is also compared for its better industrial application as a source of linoleic acid. Our study found that the sum of the oil content of the pulp and the seed was not significantly different from the oil content of the entire fruit. The present work focuses on the integral use of I. polycarpa fruit. The morphological characteristics of fruits were systematically studied, including fruit shape index, fruit dry biomass, seed number per fruit, seed dry biomass, pulp dry biomass. Gas chromatograph with a mass detector (GC/MS) analysis of fatty acid composition of fruit, pulp and seed were carried out separately. At the same time, we also carried out a correlation analysis between climatic conditions, fruit morphological characteristics and fatty acid composition. The results showed the dry weight, the seed number per fruit, and the seed dry weight are positively correlated with the oil content. The oil content of the fruit from different regions ranged from 21.27 ± 0.83% to 39.47 ± 0.32%. In fruit oil, linoleic acid is the main fatty acid. The linoleic acid content in all regions is above 60%, which is not correlated with the size of the fruit. Our results indicated that I. polycarpa is a potential woody oil plant rich in linoleic acid, which has multiple industrial applications, such as the production of alkyne resin, shoe polish, and the preparation of conjugated linoleic acid as well as varnishes. The results of the study could help us to use targeted fruit collection during fruit ripening and guide us to use the fruit for developing industrial products preparation.

The effectiveness of growth cycles on improving fruit quality for grafted watermelon combinations

Abstract Two growth cycles per year, i.e., for early growing season (EGS) and late growing season (LGS) production, both of which are widely preferred in temperate climates, have been investigated for their effects on fruit quality attributes such as appearance; firmness; the content of total soluble solids, sugars, and total phenol; and antioxidant activity. Two watermelon [Citrullus lanatus (Thunb.) Matsum and Nakai] cultivars (cv. 'Anthem F1' and cv. 'Crimstar F1') were used as scion. Two C. maxima × C. moschata hybrids (cv. 'Shintoza F90' cv. 'Obez') and one Lagenaria siceraria rootstock cv. 'Macis' were used as rootstock. Self-rooted and self-grafted plants were used as controls. EGS resulted in a reduction of fruit shape index, rind thickness, juice pH, hue values, and glucose content as compared to LGS for both the cultivars. On the other hand, total soluble solids of cv. 'Crimstar', fructose of cv. 'Anthem', and the antioxidant activity of cv. 'Anthem' increased. The total phenol content was unaffected by the scion/rootstock combinations or growth seasons for both the cultivars. Most of the fruit quality attributes increased when a specific rootstock/scion combination and growth season was used and these combinations may change in relation to cultivar. It is important to evaluate and select suitable scion/rootstocks for each growth condition created by ecology and growth cycle to guarantee high fruit quality.

The effects of planting systems on soil biology and quality attributes of tomatoes

ABSTRACTThis study was carried out to determine the effects of seedling types (grafted and non-grafted) and different plantation systems (raised-bed and flat planting) on growth, yield and quality of tomato (Solanum lycopersicum cv. Depar F1) plants organically grown in open-field conditions in Samsun. Soil microbial biomass-C increased by 25% and soil CO2 contents increased by 16% in raised-bed systems. It was observed that soil microbial biomass-C positively correlated with CO2 contents, leaf chlorophyll content, stomatal conductance and yield (P < 0.05 and P < 0.01) and negatively correlated with soil compaction. The highest chlorophyll content (47.37 CCI), fruit shape index (1.21) and yield (1.95 kg plant−1) were obtained from grafted seedlings of the raised-bed planting systems. The highest stomatal conductance (118.50 mmol m−2 s−1) and firmness (79.34%) were obtained from non-grafted seedlings of the raised-bed planting systems. As a result, successful tomato cultivation was carried out with the use of raised-bed and grafted seedlings. However, non-grafted seedlings of the raised-beds had higher yield and quality values than the grafted seedlings of the flat planting.

WATER AVAILABILITY AND POTASSIUM DOSES IN CHERRY TOMATO QUALITY

ABSTRACT The quality of cherry tomato fruits is directly related to the management strategies used in the production system, such as irrigation and fertilization. This study aimed to assess the quality of cherry tomato fruits cultivated under water availability and potassium fertilization. The experiment was carried out in a greenhouse in pots of 12 dm3 of an Oxisol. The experimental design was a randomized block design in a 52 fractional factorial arrangement with five water availabilities in the soil (4, 14, 24, 34, and 44 -kPa), five potassium doses (0, 125, 250, 375, and 500 mg dm−3) and with four blocks. Irrigation was performed with a semi-automated drip irrigation system with soil moisture monitoring by the Diviner 2000® capacitance probe. The assessed variables in fruits were longitudinal and transversal diameter and pulp thickness, fruit shape index, total soluble solids (SS), titratable acidity (TA), the SS/TA ratio, and vitamin C. The data were submitted to statistical analyses at 5% probability error, with analysis of variance by the F-test and polynomial regression. Fruit size presents a reduction as water availability decreased. The total soluble solids have a higher concentration at a potassium dose of 326 mg dm−3. The quality of cherry tomato fruits cultivated in an Oxisol is influenced by water availability and potassium doses.

Effects of balanced fertilization on growth and fruit quality of 'Huang-guan' pear on desert area.

A field experiment was carried out to study the effects of balanced fertilization on growth and development, yield, fruit quality and mineral content in 'Huang-guan' pear to provide a theoretical basis for the reasonable level of fertilization in pear orchards. Four treatments were arranged with 12-year old 'Huang-guan' pear trees from the same orchard: conventional fertilization (CK), low levels of N, P2O5 and high level of S (T1), medium levels of N, P2O5 and S (T2), high levels of N, P2O5 and low level of S (T3). The results showed that different treatments had little effect on the growth and development of current-year branch and leaves in the first year. However, in the se-cond year, T1 treatment promoted the length and diameter of current-year branch by 16.2% and 11.4%, respectively. Continuous fertilization could increase the leaf mineral contents in different degrees. The contents of Cu, Fe, and Zn in leaves under T1 treatment, Mg and B in leaves under T2 treatment, and P and Mn in leaves under T3 treatment were highest. Different fertilization levels had no significant effect on yield but on fruit quality. The contents of soluble sugars and vitamin C (Vc) were significantly increased by T2 treatment, which was 4.2% and 7.1% higher than those in CK. However, T1 significantly decreased contents of total soluble solid, soluble sugars and Vc, while highest organic acid content presented in T3. Fruit Fe content was positively correlated with soluble sugar content and fruit shape index, but was negatively correlated with single fruit mass, organic acids and Vc. Fruit P content was positively correlated with fruit shape index and firmness, but was negatively correlated with contents of soluble sugars, organic acids and Vc. Accordingly, T2 could improve fruit quality and maintain the productivity, and thus should be the suitable fertilization strategy for the 'Huang-guan' pear management in desert area.

Fruit yield and quality response of Newhall navel orange to different irrigation regimes and ground cover in Chongqing Three Gorges Reservoir area

Abstract In order to reduce unwanted negative effect of frequent rainfall in spring and high-temperature in summer on fruit yield and quality of Newhall navel orange trees in Chongqing Three-Gorges Reservoir area. In this study, the influence of Tyvek® nonwoven materials ground cover (TC) and with different irrigation density 110% (ID110), 60% (ID60), and 0 (ID0) of the local evapotranspiration (ETc) on yield and fruit quality were evaluated during three consecutive years (2015–2017) in a commercial Newhall navel orange drip irrigated orchard. During spring frequent rainfall period, all TC treatments had a significant higher in leaf sucrose content and leaf starch content during flower bloom period due to their significantly increased the leaf ACO2 exchange parameter compared to CK group. As a result, the highest in the number of fruit bearing (FBN) was obtained in TC+ID60 group due to its 84.6% and 13.5% higher the total flower number (TFN) than CK and TC+ID110 groups, respectively. However, the TC+ID110 and TC+ID0 groups had a significantly lower FBN due to their significantly 38.3% and 19.9% rate of dropped flowers (FLDR) compared to TC+ID60 group. During summer high-temperature period, the leaf water potential significantly decreased in order: TC+ID110, TC+ID60 and CK, TC+ID0, which resulted in the significant higher ACO2 and transpiration rate in TC+ID110 and TC+ID60 groups, and significant lower ACO2 and transpiration rate in TC+ID0 group. Consequently, there was a significant increase of total soluble solids, titratable acid, vitamin C in fruit internal quality and “a”, “b”, “a/b” value in fruit external quality, and a significant decrease of juice yield in fruit internal quality and fruit shape index, and weight per fruit with increasing water stress as compared to TC+ID110 group. In conclusion, TC+ID60 treatment can reduce the negative effect of frequent rainfall spring and high summer temperatures and improve the fruit yield and quality of Newhall navel oranges.

Effects of wood biochar addition on growth of cherry radish (Raphanus sativus L. var. radculus pers)

Extensive cultivation and unreasonable management of the farmland result in severe soil degradation such as compaction, acidification, and salinization. Our results showed that the biochar amendment increased the cherry radish germination rate, while barely influenced the fresh biomass of shoot and root. Moreover, both 1.5% and 3% biochar addition showed no significant difference in the fruit shape index of cherry radish compared to the control treatment. These results suggested that the biochar application alone could not improve the cherry radish growth in this tested soil. Thus, application of biochar combined with fertilizer or composted with organic wastes should be taken into account for this soil.

Characterization of IQ Domain Gene Homologs as Common Candidate Genes for Elongated Fruit Shape in Cucurbits

The SUN gene is responsible for an elongated fruit shape in tomato and belongs to the IQ domain (IQD) gene family, which is involved in growth and development in plants. In the present study, IQD gene homologs were evaluated for their roles in determining fruit shape in cucurbit crops. A total of 151 IQD homologs and their chromosomal locations in Arabidopsis, tomato, and three cucurbit species, watermelon, melon, and cucumber, were compared based on their genomic information. A phylogenetic dendrogram of these IQD homologs revealed putative orthologous and paralogous relationships among these genes, and showed that previously reported candidate fruit shape IQD genes in watermelon (ClSUN8), melon (CmSUN14), and cucumber (CsSUN2) were clustered under the same node with a similarity coefficient of 0.97. A comparison of the physical locations of the IQD homologs with fruit shape QTLs in genetic maps indicated that ClSUN8, CmSUN14, and CsSUN2 were co-localized with the major QTLs for the fruit shape index (FSI). This co-localization further indicated that minor QTLs for FSI were also associated with the IQD gene family. We used early developmental stages of immature fruits to conduct a morphological assay and characterize ClSUN8 in watermelon. Histological analysis indicated that elongated or round fruit shape is determined at the early stage of ovary formation, at least earlier than -4 days after fertilization (-4 DAF), and fruit elongation is due to increased cell division in the longitudinal direction. Quantitative RT-PCR showed that the highest expression of ClSUN8 occurred at -4 days after fertilization and gradually decreased; however, there was no direct relationship between the gene expression level and fruit shape. RACE-PCR revealed a non-synonymous SNP between the ClSUN8 alleles of elongated- and round-fruited watermelon accessions, suggesting that the SNP might be a causative mutation affecting fruit shape.

Genetic Analysis for Fruit Yield and Quality Attributes in Some Processing and Fresh Market Tomato Genotypes

ABSTRACTHigher demands for improved fruit yield and processing qualities for Tomato (Solanum lycopersicum L.) could be met through heterosis breeding. It is important to identify the parental line combination performing better for economically important quality traits. The experiment was composed of seven tomato inbred lines (two processing and five fresh market) and 21 F1 hybrids produced by crossing of them in a 7 × 7 half-diallel fashion. The nature and type of gene actions were analyzed to determine how they were involved in inheritance of fruit per plant, yield per plant, average fruit weight, total soluble solids, fruit juice pH, titratable acidity, sugar acid ratio, fruit juice content, shape index, and pericarp thickness. Most characters were predominantly controlled by nonadditive gene actions. Employing hybrid breeding for improving characters could be effective. The crosses ‘Metadel × Marglobe’, ‘Bishola × CLN2037E’, ‘Roma VF × ARP Tomato d2’, ‘Roma VF × CLN2037E’, ‘ARP Tomato d2 × Marglobe’, and ‘Eshete × CLN2037E’ showed positive and highly significant specific combining ability (SCA) effects for number of fruit per plant and fruit yield per plant. This indicated that the crosses could be used for developing high-yielding varieties. The crosses ‘Metadel × Roma VF’, ‘Bishola × Roma VF’, ‘Roma VF × Eshete’, and ‘ARP Tomato d2 × Marglobe’ exhibited positive, significant SCA effects for total soluble solids and negative, significant SCA effects for fruit juice pH. These crosses could be utilized as hybrids with better processing qualities. The crosses ‘Metadel × Marglobe’, ‘Bishola × Eshete’, ‘ARP Tomato d2 × CLN2037E’, and ‘Eshete × Marglobe’ exhibited positive, highly significant SCA effects for sugar-to-acid ratio, indicating that they could be used in hybridization for developing lines with better fruit flavor.

DETERMINATION OF HETEROSIS, GENE ACTION AND THE NATURE OF RESISTANCE TO FUSARIUM WILT DISEASE (FUSARIUM OXYSPORUM F.SP CAPSICI ) IN SWEET PEPPER HYBRIDS

Four parental genotypes from a Center of Germplasm Netherland (CGN) i.e. 1 (PI 23235), 2 (PI 17171), 3 (PI 23096) and 4 (PI 17150) and their six F1 hybrids in a diallel cross system without reciprocals were used to estimate combining ability (general and specific) and heterosis percentage relative to both mid and better parents and potence ratios for some characters in pepper (Capsicum annuum L.).The experiment was conducted at Kaha Research Farm, Kaliobia Governorate under unheated plastic house during two successive seasons 2015-2016.Survey was conducted at Kaliobia Governorate during 2015 and 2016 and the pathological studies were carried out at the Plant Pathology Research Institute, Agricultural Research center, Giza Governorate. The studies showed that Fusarium oxysporum f.sp capsici (isolate 3) was the highest in frequency and the level of pathogenicity . The susceptibility of 10 genotypes to Fusarium oxysporum f.sp. capsici (isolate 3) indicated that two F1 crosses 2 × 4 and 3 × 4 were resistant to Fusarium oxysporum f.sp. capsici (isolate 3). The correlation analysis revealed that the disease severity on roots was significantly correlated with four traits; weight/plant (kg), number of fruits /plant, number of days to 50% flower anthesis and fruit length (cm). In contrast, vascular discoloration was significantly correlated with three traits; weight/plant (kg), number of fruits /plant, and fruit length (cm). The 10 genotypes (4 parents and 6 hybrids) were evaluated for yield ;yield components and fusarium wilt resistance to determine the combining ability and heterosis effects.The obtained results reflected that the mean squares for both general combining ability (GCA) and specific combining ability (SCA) were significant for all studied traits except SCA in fruit shape index and fruit flesh thickness, suggesting the presence of both additive and non-additive gene effects in the inheritance of the various studied characters. Estimates of SCA effects showed that the F1 crosses 2 × 4 and 2 × 3 reflect the highest value in most studied traits; i.e. total yield as weight and number, fruit length and low disease severity of roots and shoots. Hybrid vigour was documented for total yield, as well as, most fruit characters and disease severity. In some crosses, high rate of parent heterosis and potence ratio values were attained for these traits supporting the over dominance hypothesis.

Association and Genetic Identification of Loci for Four Fruit Traits in Tomato Using InDel Markers.

Tomato (Solanum lycopersicum) fruit weight (FW), soluble solid content (SSC), fruit shape and fruit color are crucial for yield, quality and consumer acceptability. In this study, a 192 accessions tomato association panel comprising a mixture of wild species, cherry tomato, landraces, and modern varieties collected worldwide was genotyped with 547 InDel markers evenly distributed on 12 chromosomes and scored for FW, SSC, fruit shape index (FSI), and color parameters over 2 years with three replications each year. The association panel was sorted into two subpopulations. Linkage disequilibrium ranged from 3.0 to 47.2 Mb across 12 chromosomes. A set of 102 markers significantly (p < 1.19–1.30 × 10−4) associated with SSC, FW, fruit shape, and fruit color was identified on 11 of the 12 chromosomes using a mixed linear model. The associations were compared with the known gene/QTLs for the same traits. Genetic analysis using F2 populations detected 14 and 4 markers significantly (p < 0.05) associated with SSC and FW, respectively. Some loci were commonly detected by both association and linkage analysis. Particularly, one novel locus for FW on chromosome 4 detected by association analysis was also identified in F2 populations. The results demonstrated that association mapping using limited number of InDel markers and a relatively small population could not only complement and enhance previous QTL information, but also identify novel loci for marker-assisted selection of fruit traits in tomato.