Carotene Accumulation Research Articles

Practical application of heterosis on yield evidence and fruits biochemical composition for tomato (Solanum lycopersicum L.) in open ground

Relevance. The research is devoted to studying the peculiarities of the high-parent heterosis manifestation which connected with yield traits and the biochemical composition of tomato fruits.Materials and Methods. The work was carried out in 2021–2023 in open field conditions on the experimental plot of the Belarusian State Agricultural Academy (Mogilev region, Belarus). The objects of research were 30 F1 hybrids and 11 parental forms with different levels of economically valuable traits and with the specific set of genes for pathogen resistance and lycopene accumulation. The aim of the research was to create high-yield heterotic F1 tomato hybrids, adapted to open field conditions in Belarus, with a valuable biochemical composition of fruits.Results. The best hybrid combinations showed an early yield of 0.90–2.49 kg/m2, a marketable yield of 7.50–11.40 kg/m2, and a total yield of 8.22–13.12 kg/m2. High heterosis effect was established for early (88.9–291.0%), marketable (36.0–111.2%), and total (28.6–97.8%) yield in some hybrids. Significant differences in the accumulation of dry matter, carotene, and soluble carbohydrates were ascertained between the hybrids. Hybrid combinations with the highest value of true heterosis on accumulation of dry matter (18.3–21.6%), carotene (20.2–22.9%), and soluble carbohydrates (15.7–38.9%) were identified. Inheritance of early, marketable and total yield, dry matter content, carotene and soluble carbohydrates predominantly took place according to the positive overdominance, fruit weight – according to the intermediate inheritance, vitamin C content – according to the negative overdominance. Hybrids Brusnichny F1, Mansiata F1, Rada F1 were transferred to the State Inspection for Testing and Protection of Plant Varieties of the Republic of Belarus and successfully passed the testing stage in 2023.

D-cysteine desulfhydrase silence influences the level of sugar, organic acid, carotenoids, and polyphenols in tomato fruit

Hydrogen sulfide (H2S) plays important roles in the regulation of fruit ripening. D-cysteine desulfhydrase (DCD) is one of the key enzymes of H2S synthesis. However, whether and how DCD is involved in the regulation of tomato fruit quality is still unknown. Here, the tobacco rattle virus (TRV)-based virus-induced gene-silencing (VIGS) was used to silence DCD to explore the effect of DCD on quality regulation in postharvest tomato fruit. The results revealed that DCD silence accelerated the accumulation of fructose, glucose, soluble sugar, soluble protein, carotene, and lycopene. The expressions of the major genes (PFPP, ATPPF, FBA6; GPI, GPD1, POL2; ZDS, CCD7, CrtL-e-1, psy1, LCY1 and PDS) in sugar, acid and carotene metabolism were up-regulated in DCD-silenced tomatoes. DCD silence also decreased the content of malic acid, citric acid, ascorbic acid, total phenols, and total flavonoid by reducing the transcriptional level of their metabolism related genes (MDH, ME1, ME2; CSG, CS3, CSM; MDHAR and DHAR1; PAL5, 4CL, CHS2 and F3H). Meanwhile, the effects of DCD silence on tomato fruit were reversed by the addition of H2S. Thus, H2S might regulate the quality of postharvest tomato fruit through a DCD-dependent pathway.

The transcription factor IbNAC29 positively regulates the carotenoid accumulation in sweet potato.

Carotenoid is a tetraterpene pigment beneficial for human health. Although the carotenoid biosynthesis pathway has been extensively studied in plants, relatively little is known about their regulation in sweet potato. Previously, we conducted the transcriptome database of differentially expressed genes between the sweet potato (Ipomoea batatas) cultivar 'Weiduoli' and its high-carotenoid mutant 'HVB-3'. In this study, we selected one of these candidate genes, IbNAC29, for subsequent analyses. IbNAC29 belongs to the plant-specific NAC (NAM, ATAF1/2, and CUC2) transcription factor family. Relative IbNAC29 mRNA level in the HVB-3 storage roots was ~1.71-fold higher than Weiduoli. Additional experiments showed that the contents of α-carotene, lutein, β-carotene, zeaxanthin, and capsanthin are obviously increased in the storage roots of transgenic sweet potato plants overexpressing IbNAC29. Moreover, the levels of carotenoid biosynthesis genes in transgenic plants were also up-regulated. Nevertheless, yeast one-hybrid assays indicated that IbNAC29 could not directly bind to the promoters of these carotenoid biosynthesis genes. Furthermore, the level of IbSGR1 was down-regulated, whose homologous genes in tomato can negatively regulate carotene accumulation. Yeast three-hybrid analysis revealed that the IbNAC29-IbMYB1R1-IbAITR5 could form a regulatory module. Yeast one-hybrid, electrophoretic mobility shift assay, quantitative PCR analysis of chromatin immunoprecipitation and dual-luciferase reporter assay showed that IbAITR5 directly binds to and inhibits the promoter activity of IbSGR1, up-regulating carotenoid biosynthesis gene IbPSY. Taken together, IbNAC29 is a potential candidate gene for the genetic improvement of nutritive value in sweet potato.

Сравнительный анализ кормовой ценности сортов суданской травы в условиях Карагандинской области

The article presents the results of an experiment on the cultivation of three varieties of Sudanese grass in the conditions of Karaganda city. Sudanese grass is a heat-loving valuable food crop with high drought resistance. It is cultivated to produce green feed, hay, silage. It is a rich source of vitamins, proteins, minerals. The results of field experiments showed that cryopreservation of Sudanese grass seeds had a positive effect on the productivity of the aboveground mass. Excess in terms of yield indicators for the “Novosibirsk 84” variety is 38.85 c/ha for raw weight and 58.80 c/ha for dry weight; for the “Nika” variety — by 23.55 and 41.25 c/ha, respectively; for the “Tugai” variety — 8.55 and 8.55 c/ha, respectively. According to the fodder value analysis, all three varieties of Sudanese grass have good nutrition of aboveground organs. Varieties differ slightly in the accumulation of starch, sugar, raw protein, ash, carotene, calcium, and phosphorus. Preliminary data make it possible to distinguish the “Novosibirsk 84” variety with the maximum yield, and the “Tugai” variety with the maximum accumulation of elements of fodder value.

Differential hydroxylation efficiency of the two non-heme carotene hydroxylases: DcBCH1, rather than DcBCH2, plays a major role in carrot taproot.

Carotene hydroxylase plays an important role in catalyzing the hydroxylation of carotene to xanthopylls, including two types: non-heme carotene hydroxylase (BCH type) and heme-containing cytochrome P450 hydroxylase (P450 type). Two BCH-encoding genes were annotated in the carrot genome. However, the role of BCHs and whether there are functional interactions between the duplicated BCHs in carrot remains unclear. In this study, two BCH encoding genes, DcBCH1 and DcBCH2, were cloned from carrot. The relative expression level of DcBCH1 was much higher than that of DcBCH2 in carrot taproots with different carotene accumulation levels. Overexpression of DcBCH1 in 'KRD' (high carotene accumulated) carrot changed the taproot color from orange to yellow, accompanied by substantial reductions in α-carotene and β-carotene. There was no obvious change in taproot color between transgenic 'KRD' carrot overexpressing DcBCH2 and control carrot. Simultaneously, the content of α-carotene in the taproot of DcBCH2-overexpressing carrot decreased, but the content of β-carotene did not change significantly in comparison with control carrot. Using the CRISPR/Cas9 system to knock out DcBCH1 in 'KRD' carrot lightened the taproot color from orange to pink-orange; the content of α-carotene in the taproot increased slightly, while the β-carotene content was still significantly decreased, compared with control carrot. In DcBCH1-knockout carrot, the transcript level of DcBCH2 was significantly increased. These results indicated that in carrot taproot, DcBCH1 played the main function of BCH enzyme, which could hydroxylate α-carotene and β-carotene; DcBCH1 and DcBCH2 had functional redundancy, and these two DcBCHs could partially compensate for each other.

Characterization and production potential of carotenes in Peruvian strains of Dunaliella salina Teodoresco

AbstractChlorophyte microalgae Dunaliella are halophilic flagellated cells; they can resist high salinities, producing β‐carotene to balance osmotic stress. This pigment has important antioxidant properties for biotechnology, the prevention of tissue aging, the efficiency of the immune system, and sun protection against UV‐B rays. The objective of this study was to characterize native strains of the genus Dunaliella from the Marine Institute of Peru, under the influence of stress factors for the production and concentration of β‐carotene. Different tools were used to characterize these strains through molecular analysis, optimization of parameters for carotene accumulation, growth curves, life cycle, and carotene analysis. The accumulation of this pigment was mainly due to adaptation to salt stress. The differences between Dunaliella strains according to their population growth demonstrated that they did not have the same capacity to respond to the same cultivation conditions, although most of them are from the same species. The IMP‐BG‐001 strain, from Piura, can accumulate high concentrations of β‐carotene (up to 8.64 pg/cell) and still maintain a considerable growth rate without affecting the increase in biomass under controlled conditions.

Response of some maize hybrids (Zea mays L.) for foliar application by polyisoprenic on bioactive components grown under middle Egyptian conditions

Grains of three maize hybrids grown in the middle Egypt zone were obtained and investigated for study the effect of spraying treatment with two β-carotene (βC) levels and natural carotenoids extract (NCE). The maize hybrids are yellow hybrid (No. 352) Yellow hybrid (No.178) and High Tec. White(No.2031). Results indicate that the most efficient solvent for carotenoids extraction is boiled methanol whereas the extract weight reached to be 0.913 and 0.9692 g/250 g dry weight grains followed by chloroform and ethanol. Application results of βC and NCE on crude lipids show that yellow hybrid (No. 352) recorded the highest levels followed by yellow hybrid (No. 178) and the lowest levels are recorded in High Tec. White (No. 2130). The concentrations with 7.5 and 15 µg/mL βC are better than NCE. It could be concluded that response of lipids in maize hybrids for foliar application are low. The yellow corn genotypes studied here are characterized with high levels of different isoforms of carotenes and xanthophylls and the results show that the most predominant carotene is β-carotene and the three predominant xanthophyll are zeaxanthin folowed by lutein and β-cryptoxanthin. Total carotenoids in untreated and treated samples ranged from 47.63 to 568.49 µg /g and the highest concentration was recorded with 15 ppm β-carotene as foliar spraying. The Yellow hybrid (No.178) contains higher concentrations from lutein, zeaxanthin, b-cryptoxanthin and b-caotene compared with Yellow hybrid (No.352) and High Tec. White (No.2031). Generally, provitamin A carotenoid constitute 7.65-39.34 % of total carotenoids in maize, whereas zeaxanthin and lutein each commonly represent 30–50 %. Results show that the provitamin A carotenoid compose one third and xanthophyll carotenoids reached to be two thirds. The amounts of provitamin A in traditional yellow maize varieties range from 0.25 μg to 2.5 μg g-1 dry weight. Results obtained here, indicate that spraying with polyisoprenic led to the accumulation of xanthophylls with 60% and carotenes with 40%. The precursors of vitamin A are less and this is due to the genotypes behavior under study which directed to the accumulation of both xanthophylls and carotenes, but the xanthophylls were predominant and higher.

Transcriptional Analysis of Carotenoids Accumulation and Metabolism in a Pink-Fleshed Lemon Mutant.

Pink lemon is a spontaneous bud mutation of lemon (Citrus limon, L. Burm. f) characterized by the production of pink-fleshed fruits due to an unusual accumulation of lycopene. To elucidate the genetic determinism of the altered pigmentation, comparative carotenoid profiling and transcriptional analysis of both the genes involved in carotenoid precursors and metabolism, and the proteins related to carotenoid-sequestering structures were performed in pink-fleshed lemon and its wild-type. The carotenoid profile of pink lemon pulp is characterized by an increased accumulation of linear carotenoids, such as lycopene, phytoene and phytofluene, from the early stages of development, reaching their maximum in mature green fruits. The distinctive phenotype of pink lemon is associated with an up-regulation and down-regulation of the genes upstream and downstream the lycopene cyclase, respectively. In particular, 9-cis epoxycarotenoid dioxygenase genes were overexpressed in pink lemon compared with the wild-type, suggesting an altered regulation of abscisic acid biosynthesis. Similarly, during early development of the fruits, genes of the carotenoid-associated proteins heat shock protein 21, fibrillin 1 and 2 and orange gene were overexpressed in the pulp of the pink-fleshed lemon compared to the wild-type, indicating its increased capacity for sequestration, stabilization or accumulation of carotenes. Altogether, the results highlighted significant differences at the transcriptomic level between the pink-fleshed lemon and its wild-type, in terms of carotenoid metabolism and the capacity of stabilization in storage structures between the two accessions. Such changes may be either responsible for the altered carotenoid accumulation or in contrast, a metabolic consequence.

Development of high-lycopene tomato hybrids using conventional breeding techniques and molecular markers

Relevance. High lycopene fruit content has been regarded as a very important genetic trait in tomato breeding. Use lycopene molecular markers in combination with conventional breeding techniques allowed us to create hybrids with high lycopene accumulation, excellent organoleptic qualities, high yield production and resistance to pathogens, and to effectively optimize our breeding programmes for commercial greehouses production.Material and Methods. In this study tomato samples including selected lines and hybrids with various allelic combinations of genes determining carotene accumulation, and other genetic traits, such as disease resistance and yield production were tested. Introgression of spontaneous and induced mutations was used to increase carotenoid levels (og and hp) and improve fruit technological qualities (nor, alc, rin). The research material was tomato collection, mutants, breeding lines and hybrids listed in the State Register Russian Federation tomato hybrids of breeding SS Agrofirm "Ilyinichna" VNIIO branch of the All-Russian Scientific Research Institute of Vegetable Growing – Branch of the FSBSI Federal Scientific Vegetable Center. DNA typing of fruit quality genes was performed at the Institute of Genetics and Cytology of the National Academy of Sciences of Belarus.Results. New domestic hybrids for industrial greenhouses, which characterised by improved organoleptic qualities and technological traits were developed with the help of phasedcross-breeding that allowed to combine the genes nor, rin, alc, leading to an extension of the shelf life with the genes B, og, hp1, etc., contributing to an increase in carotenoid content in fruits. It was established that for targeted selection and hybridization, despite the negative influence of the nor, rin, alc genes it is possible to raise the level of carotenoids to average values. Correlation between lycopene concentration in fruits and high temperature and level of insolation was confirmed. It was shown that pink-fruited forms contain significantly more lycopenethanred-fruitedones. Different all eliccombinations of structural genes involved in carotenoids biosynthesis and regulatory genes that provided maximal accumulation of lycopene in hybrid swithred and pink fruits were revealed. Hybrids with the combination of high concentrations of sugar (° Brix), dry matter and maximal lycopene values, combined defining excellent taste were selected: Prekrasnaiya lady, Olya, Quadrille, Victoria. New F1 hybrids one for industrial greenhouses: G950, G956, G960, Magistral and pink fruited G12897, surpassed the Dutch standard in productivity up to 21%, and in tastes/organoleptic qualities for 1-1.8 points.

Plant Biostimulant Effects of Baker’s Yeast Vinasse and Selenium on Tomatoes through Foliar Fertilization

The application of selenium (Se) to tomatoes enhances accumulation of bioactive compounds. The physiological window of Se is very narrow, and Se overdose reduces the yield. Glycine betaine was shown to reduce Se’s negative effects on plants and to potentiate its beneficial effects. In this study, baker’s yeast vinasse (BYV), as an affordable source of glycine betaine, was tested for its interaction with Se in an optimized foliar fertilizer. The application dose was selected after a laboratory experiment, wherein assays on plant height, leaves surfaces, stomatal conductance, and chlorophyll fluorescence were done. The Se and BYV supplemented foliar fertilizers were tested for their effects on accumulation of bioactives in drip-irrigated tomatoes cultivated in a greenhouse. Under laboratory conditions, assays demonstrated Se and BYV induced effects on tomatoes plants. Both the stomatal conductance and photosynthesis efficiency increased compared to a water treated control. The greenhouse experiment demonstrated that BYV and Se addition increases the number of tomato fruits in the “extra” marketable class and enhances the accumulation of ascorbic acid, carotenes, polyphenols, and flavonoids. The effects depend on the composition of the foliar fertilizer, the most significant effects being recorded for the foliar applied product with the highest BYV and nitrogen content.

Comparative evaluation of different carbon sources supply on simultaneous production of lipid and carotene of Rhodotorula glutinis with irradiation and the assessment of key gene transcription

To investigate the feasibility of simultaneously enhancing lipid and carotene production by irradiation with different carbon sources, a strategy by controlling the carbon sources supply were selected to culture Rhodotorula glutinis under the irradiation condition. The results demonstrated that the irradiation indeed enhanced cell growth, lipid and carotene production with different carbon sources supply. Besides, the fatty acids profiling as revealed by more unsaturated fatty acids (mainly C16:1, C18:2 and C18:3) and less saturated fatty acids (C18:0, C22:0 and C24:0) were found during the process of irradiation. Compared with the control, the increase of the transcription levels in genes connected with substrates assimilation, lipid production and carotene accumulation were observed under the irradiation condition. The results suggest the possibility of using irradiation as an effective strategy to increase the production of both lipid and carotene with the controlled carbon sources supply.

High hydrostatic pressure treatments trigger de novo carotenoid biosynthesis in papaya fruit (Carica papaya cv. Maradol).

High hydrostatic pressure (HHP) processing is a non-thermal technology reported to increase desirable metabolites in plant foods. This work evaluated changes in carotenoid accumulation in fresh-cut papaya fruit as affected by HHP treatment (50-400 MPa for 3-60 min) and during subsequent storage at 4 °C; simultaneously, transcriptional activities of carotenoid biosynthetic genes and oxidative stress markers were evaluated. LC-MS analyses revealed that HHP treatment increased carotenoid precursors and carotenes contents following processing and storage: lycopene levels increased up to 11-fold compared to the non-treated samples, and H2O2 and lipid peroxidation were concomitantly increased. qRT-PCR of intact RNA showed that the amount of phytoene desaturase transcripts increased after HHP treatment, and that they were correlated with carotene accumulation. This is the first study to show that HHP treatment triggers de novo carotenoid biosynthesis, which is regulated at the transcriptional level, possibly by inducing oxidative stress signaling in fruit tissue.

Exogenously applied auxins and cytokinins ameliorate lead toxicity by inducing antioxidant defence system in green alga Acutodesmus obliquus

The effects of auxins (IAA, IBA, PAA) and cytokinins (tZ, Kin, DPU) on the growth, oxidative damage, level of antioxidants and the activity of antioxidant enzymes as well as the contents of proteins and photosynthetic pigments in green alga Acutodesmus obliquus were investigated under 100 μM lead (Pb) stress. Heavy metal induced oxidative damage as evidenced by a decrease in cell number and reduction in the contents of proteins and chlorophylls as a consequence of an increase in reactive oxygen species (ROS) formation and lipid peroxidation. The application of exogenous auxins and cytokinins modulated biosorption of Pb by algal cells significantly alleviated the growth inhibition and stimulated the accumulation of proteins, chlorophylls and carotenes. Phytohormones also activated the xanthophyll cycle which is extensively involved in the protection of the photosynthetic apparatus in adverse environmental conditions. The reduction in oxidative stress caused by the presence of toxic Pb was observed in algal cultures treated with phytohormones. Cytokinins were more effective in lowering hydrogen peroxide and lipid peroxidation levels in comparison with auxins. This improving effect of cytokinins seems to be mediated by a decrease in Pb accumulation by algal cells, whereas auxins promoted metal uptake. Importantly, auxins and cytokinins enhanced the redox status of algal cells inducing the increase in the content of antioxidants (ascorbate, glutathione, and proline) and in the activity of antioxidant enzymes (superoxide dismutase, catalase, ascorbate peroxidase, and glutathione reductase) involved in ROS scavenging. The results of the present study strongly suggest that exogenous auxins and cytokinins enhanced the resistance of microalga A. obliquus against Pb toxicity through the activation of the antioxidant defence system.

Investigating the frequency of alleles of <i> crtRB1 </i> and <i> LcyE </i> genes that are favoable for -carotene accumulation in some maize lines cultivated in VietNam

Investigating the frequency of alleles of <i> crtRB1 </i> and <i> LcyE </i> genes that are favoable for -carotene accumulation in some maize lines cultivated in VietNam

Intercropping Induces Changes in Specific Secondary Metabolite Concentration in Ethiopian Kale (Brassica carinata) and African Nightshade (Solanum scabrum) under Controlled Conditions.

Intercropping is widespread in small-holder farming systems in tropical regions and is also practiced in the cultivation of indigenous vegetables, to alleviate the multiple burdens of malnutrition. Due to interspecific competition and/or complementation between intercrops, intercropping may lead to changes in plants accumulation of minerals and secondary metabolites and hence, alter nutritional quality for consumers. Intercropping aims to intensify land productivity, while ensuring that nutritional quality is not compromised. This study aimed to investigate changes in minerals and secondary plant metabolites in intercropped Brassica carinata and Solanum scabrum, two important African indigenous vegetables, and evaluated the suitability of this combination for dryer areas. B. carinata and S. scabrum were grown for 6 weeks under controlled conditions in a greenhouse trial. Large rootboxes (8000 cm3 volume) were specifically designed for this experiment. Each rootbox was planted with two plants, either of the same plant species (mono) or one of each plant species (mixed). A quartz sand/soil substrate was used and fertilized adequately for optimal plant growth. During the last 4 weeks of the experiment, the plants were either supplied with optimal (65% WHC) or low (30% WHC) irrigation, to test the effect of a late-season drought. Intercropping increased total glucosinolate content in B. carinata, while maintaining biomass production and the contents of other health related minerals in both B. carinata and S. scabrum. Moreover, low irrigation led to an increase in carotene accumulation in both mono and intercropped S. scabrum, but not in B. carinata, while the majority of kaempferol glycosides and hydroxycinnamic acid derivatives of both species were decreased by intercropping and drought treatment. This study indicates that some health-related phytochemicals can be modified by intercropping or late-season drought, but field validation of these results is necessary before definite recommendation can be made to stakeholders.

Cytological and molecular characterization of carotenoid accumulation in normal and high-lycopene mutant oranges

Ripe Cara Cara sweet orange contains 25 times as much carotenoids in flesh as Newhall sweet orange, due to high accumulation of carotenes, mainly phytoene, lycopene and phytofluene. Only yellow globular chromoplasts were observed in Newhall flesh. Distinct yellow globular and red elongated crystalline chromoplasts were found in Cara Cara but only one type of chromoplast was present in each cell. The red crystalline chromoplasts contained lycopene as a dominant carotenoid and were associated with characteristic carotenoid sequestering structures. The increased accumulation of linear carotenes in Cara Cara is not explained by differences in expression of all 18 carotenogenic genes or gene family members examined, or sequence or abundance of mRNAs from phytoene synthase (PSY) and chromoplast-specific lycopene β-cyclase (CYCB) alleles. 2-(4-Chlorophenylthio)-triethylamine hydrochloride (CPTA) enhanced lycopene accumulation and induced occurrence of red crystalline chromoplasts in cultured Newhall juice vesicles, indicating that carotenoid synthesis and accumulation can directly affect chromoplast differentiation and structure. Norflurazon (NFZ) treatment resulted in high accumulation of phytoene and phytofluene in both oranges, and the biosynthetic activity upstream of phytoene desaturase was similar in Newhall and Cara Cara. Possible mechanisms for high carotene accumulation and unique development of red crystalline chromoplasts in Cara Cara are discussed.

Biogenesis and possible modification of carotenoid composition in the eyespot of Chlamydomonas reinhardtii mutants

Biogenesis of the eyespot ultrastructure in the chloroplasts of the mutants of unicellular green algae Chlamydomonas renihardtii was studied. Development of the eyespot ultrastructure was found to correlate with carotenoid accumulation. Depending on their content, the eyespot formed 1 to 5 layers of lipid-carotenoid globules. Accumulation of carotene in the eyespot globules was shown. It was found that carotene composition in the eyespot of the mutants could vary depending on their composition in the chloroplast membranes.

Effect of aqueous 1-methylcyclopropene in delaying postharvest ripening of breaker-turning tomato fruit

The effect of aqueous 1–methylcyclopropene (1–MCP) was investigated on ripening and quality of tomato (Solanun lycopersicum L.) during storage. Tomato fruits of cv. 'BARI Tomato–15' at breaker–turning stage were immersed in 100, 200, 300 and 400 µg L−1 of 1–MCP for 5 minutes, air–dried, packed in 1% perforated low density polyethylene bag and stored at 20 ± 2°C with 75%–80% RH for 24 days. The rate of respiration was strongly suppressed with higher concentrations of 200, 300 and 400 µg L−1 during storage. Similarly, tissue softening, rate of β–carotene accumulation and fruit surface colour were markedly delayed with higher concentrations of 1–MCP and consequently extended at least 12 days extra storage life compared to control treatment. The results demonstrated the efficacy of aqueous 1–MCP and imply prospects for the postharvest application at 200 µg L−1 for prolonging the storage life of tomato up to 24 days at 20 ± 2°C and 75%–80% RH maintaining better fruit quality.

Mapping of or, a gene conferring orange color on the inner leaf of the Chinese cabbage (Brassica rapa L. ssp. pekinensis)

The orange inner leaf of the Chinese cabbage is controlled by a single recessive gene (or), which causes abnormal accumulation of carotene. In the present study, an F2 population consisting of 600 individuals was used for mapping or and developing new markers closely linked to this gene. Bulked segregant analysis was performed by screening 435 simple sequence repeat (SSR) markers well-distributed on 10 linkage groups and 16 SSR primers derived from nine bacterial artificial chromosome (BAC) clones. On the basis of linkage analysis, the or gene was mapped in a region covering a total interval of 4.6 centimorgans (cM) between two SSR markers derived from BAC clones AC172873 and AC189246 at the end of linkage group 9, which matches with chromosome 1 of A genome in Chinese cabbage. A genetic map of the or locus was constructed by using five SSR markers and two morphological markers. Three SSR markers were tightly linked to or and two of them, sau (C) 586 and syau19, were located on the same side at distances of 1.6 and 1.3 cM, respectively. The other marker, syau15, was located on the other side at a distance of 3.3 cM. The two morphological markers, orange flower and orange cotyledon (before cotyledon turns green during the germination period), were obtained by visual determination and screening of the differences in the morphological traits between parents and the two segregated F2 populations; the two markers were designated as or-f (orange flower) and or-c (orange cotyledon). It was suggested that these two markers co-segregate with orange inner leaf trait or that the three characters, namely orange inner leaf, orange flower, and orange cotyledon, are determined by the same gene. These markers could be very helpful for marker-assisted selection in Chinese cabbage hybrid breeding programs.

Evaluation of Scar18 Marker Linked to B-Carotene for Early Screening of Mango (Mangifera indica L.) Progenies

A breeding program of Mango (Mangifera indica) was organized by a team of Brawijaya University since 2006 by cross pollination between Arumanis 143 (green skin) with yellow skin cvs. of Carabao, Haden, Podang and Swarnarika in vice versa. As early identification a molecular evaluation was conducted. Measurement were on carotene content, DNA analysis using PCR and sequencing. The result showed that mango cultivars having orange or yellowish skin contain carotene higher than those mango cultivar having green skin. SCAR18 marker as a sign on the presence of beta (B) locus in tomato was not related with the differences of beta carotene accumulation in those manggo cultivars. SCAR18 marker that was amplified in mango produced specific amplimer of 320 bp in length. The similarity of SCAR18320 sequence obtaining by sequences alignment among five parental cultivars and 12 hybrids was up to 100%. SCAR18320 sequences that were generated by SCAR18 markers as predicted beta (B) loci had no significant similarity with sequences database relating to beta (B) gene in NCBI. SCAR18320 match to 19 Ty3-gypsy retrotransposons and others sequences related transcriptional regulator in more dissimilar sequences (discontiguous megablast) category. Keywords: SCAR18, ? carotene, skin color, Mangifera indica