Genotypic Variability in Tomato for Total Carotenoids and Lycopene Content during Summer and Response to Post Harvest Temperature

Lycopene is the major carotenoid responsible for fruit colour in tomato (Lycopersicon esculentum Mill.). However, colour of the fruit is greatly affected by high temperature prevailing during fruit growth in the summer crop. To select a genotype suitable for summer conditions that can maintain colour better, a set of 52 tomato genotypes were evaluated for lycopene, total carotenoids and for TSS during summer in Bengaluru. Among the genotypes screened, IIHR 2892 recorded very high lycopene content (328.4mg/100g dry weight) and IIHR 2866 recorded very low lycopene content (25.2mg/100g dry weight). TSS values ranged from 2.6° Brix in cv. Vybhav to 7.0° Brix in IIHR 2866. In addition, study was carried out to determine the effect of postharvest temperature on biosynthesis of lycopene in five selected tomato cultivars (Arka Rakshak, Arka Samrat, Arka Ananya, Lakshmi and Abhinava). Tomatoes harvested at breaker stage were stored at 27° C, 35° C and 40° C for ripening. High temperature reduced lycopene content in tomato fruits. Lycopene synthesis in fruits was completely inhibited above 35°C. In this study, mean lycopene content in tomatoes stored at 27° C was 3-4 times higher than that in tomatoes stored at 40° C. This indicates that in tomatoes, temperature at which the fruits are stored after harvest, is a more important factor for colour development

Changes in Fruit Quality and Carotenoid Profile in Tomato (Solanum lycopersicon L.) Genotypes under Elevated Temperature

Tomato (Solanum lycopersicon L.) is a rich source of carotenoids, especially lycopene, and is affected severely by high temperatures under tropical conditions. To study the effect of elevated temperature on lycopene content and other quality parameters, five tomato genotypes, viz., RF4A, Abhinava, Arka Saurabh, IIHR 2195 and Arka Vikas, were grown in a temperature gradient tunnel (TGT) facility under 33.4 and 35.4°C temperature conditions. Fruits were analyzed for total carotenoids, total phenols, total flavonoids, total sugars, TSS, acidity, Vitamin C besides carotenoids profile (β-carotene, lycopene, phytoene and luteoxanthin content). Results revealed that all the quality parameters studied were superior at 33.4°C, compared to 35.4°C in all the genotypes. 'IIHR 2195' recorded highest total phenols (479.28mg/100g dw), total flavonoids (70.27mg/100g dw), ferric reducing antioxidant potential (FRAP) (310.53mg/100g dw), diphenyl picryl hydrazyl (DPPH) radical (487.89mg/100g dw), Vitamin C content (292.25mg/ 100g dw) and total sugars (606.88mg/g dw) at 33.4°C and at 35.4°C. 'RF4A' and 'Arka Vikas' were found to have better total carotenoids content and lycopene at higher temperature than other genotypes. 'Arka Vikas' recorded highest total soluble solids (TSS) (8.9°Brix) and acidity (0.80%) at 35.4°C. Higher TSS and acidity were recorded at 35.4°C than at 33.4°C in all the five genotypes. Genotypic variation was observed in the above stated biochemical parameters in response to elevated temperatures

Breeding tomato (Solanum lycopersicum L.) for resistance to biotic and abiotic stresses

Tomato (Solanum lycopersicum L.) is an important vegetable crop cultivated in the tropical and sub-tropical regions of the world. Low productivity in India is due to occurrence of both biotic and abiotic stresses. Among the biotic stresses, tomato leaf curl disease, bacterial wilt, early blight and Groundnut Bud Necrosis Virus disease have become serious production constraints causing considerable yield loss in the major tomato growing areas of the country. Adoption of multiple disease resistant varieties or F1 hybrids would be the most appropriate way to address these diseases. At ICAR-IIHR, Bengaluru systematic breeding strategies were employed to pyramid genes for resistance to early blight, bacterial wilt and tomato leaf curl diseases and to develop advanced breeding lines& F1 hybrids with triple disease resistance. Stable source of resistance to early blight and bi-partite begomo-virus (Tomato Leaf Curl New Delhi Virus) has been identified in Solanum habrochaites LA-1777. Validation with molecular markers linked to tomato leaf curl virus resistance revealed that LA-1777 carryTy2 and other putative resistant genes. Several high yielding dual purpose hybrids were also developed for fresh market and processing with high level of resistance to multiple diseases. Cherry tomato lines have also been bred for high TSS, total carotenoids, total phenols, flavonoids, vitamin C, acidity and lycopene content. IIHR-249-1, IIHR-2101 (Solanum habrochaites LA-1777), IIHR- 2866 and IIHR-2864 recorded high values for quality parameters like total carotenoids, lycopene, vitamin C, total phenols, flavonoids and TSS. Drought tolerant root stock has been developed by an interspecific cross between S. habrochaites LA-1777 and S. lycopersicum (15 SB SB). Resistant sources have also been identified against Tuta absoluta, a serious insect pest reported from major tomato growing areas in the country in recent time. High temperature tolerant breeding lines are in pipe line

Searches for Ultra-High-Energy Photons at the Pierre Auger Observatory

The Pierre Auger Observatory, being the largest air-shower experiment in the world, offers an unprecedented exposure to neutral particles at the highest energies. Since the start of data taking more than 18 years ago, various searches for ultra-high-energy (UHE, $E\gtrsim10^{17}\,\text{eV}$) photons have been performed: either for a diffuse flux of UHE photons, for point sources of UHE photons or for UHE photons associated with transient events like gravitational wave events. In the present paper, we summarize these searches and review the current results obtained using the wealth of data collected by the Pierre Auger Observatory.Comment: Review article accepted for publication in Universe (special issue on ultra-high energy photons

A Catalog of the Highest-energy Cosmic Rays Recorded during Phase I of Operation of the Pierre Auger Observatory

A catalog containing details of the highest-energy cosmic rays recorded through the detection of extensive air-showers at the Pierre Auger Observatory is presented with the aim of opening the data to detailed examination. Descriptions of the 100 showers created by the highest-energy particles recorded between 1 January 2004 and 31 December 2020 are given for cosmic rays that have energies in the range 78 EeV to 166 EeV. Details are also given of a further nine very-energetic events that have been used in the calibration procedure adopted to determine the energy of each primary. A sky plot of the arrival directions of the most energetic particles is shown. No interpretations of the data are offered

Constraining the sources of ultra-high-energy cosmic rays across and above the ankle with the spectrum and composition data measured at the Pierre Auger Observatory

In this work we present the interpretation of the energy spectrum and mass composition data as measured by the Pierre Auger Collaboration above $6 \times 10^{17}$ eV. We use an astrophysical model with two extragalactic source populations to model the hardening of the cosmic-ray flux at around $5\times 10^{18}$ eV (the so-called "ankle" feature) as a transition between these two components. We find our data to be well reproduced if sources above the ankle emit a mixed composition with a hard spectrum and a low rigidity cutoff. The component below the ankle is required to have a very soft spectrum and a mix of protons and intermediate-mass nuclei. The origin of this intermediate-mass component is not well constrained and it could originate from either Galactic or extragalactic sources. To the aim of evaluating our capability to constrain astrophysical models, we discuss the impact on the fit results of the main experimental systematic uncertainties and of the assumptions about quantities affecting the air shower development as well as the propagation and redshift distribution of injected ultra-high-energy cosmic rays (UHECRs).Comment: Submitted to JCA

Constraining the sources of ultra-high-energy cosmic rays across and above the ankle with the spectrum and composition data measured at the Pierre Auger Observatory

In this work we present the interpretation of the energy spectrum and mass composition data as measured by the Pierre Auger Collaboration above 6 × 1017 eV. We use an astrophysical model with two extragalactic source populations to model the hardening of the cosmic-ray flux at around 5 × 1018 eV (the so-called "ankle"feature) as a transition between these two components. We find our data to be well reproduced if sources above the ankle emit a mixed composition with a hard spectrum and a low rigidity cutoff. The component below the ankle is required to have a very soft spectrum and a mix of protons and intermediate-mass nuclei. The origin of this intermediate-mass component is not well constrained and it could originate from either Galactic or extragalactic sources. To the aim of evaluating our capability to constrain astrophysical models, we discuss the impact on the fit results of the main experimental systematic uncertainties and of the assumptions about quantities affecting the air shower development as well as the propagation and redshift distribution of injected ultra-high-energy cosmic rays (UHECRs)

A Catalog of the Highest-energy Cosmic Rays Recorded during Phase I of Operation of the Pierre Auger Observatory

A catalog containing details of the highest-energy cosmic rays recorded through the detection of extensive air showers at the Pierre Auger Observatory is presented with the aim of opening the data to detailed examination. Descriptions of the 100 showers created by the highest-energy particles recorded between 2004 January 1 and 2020 December 31 are given for cosmic rays that have energies in the range 78–166 EeV. Details are also given on a further nine very energetic events that have been used in the calibration procedure adopted to determine the energy of each primary. A sky plot of the arrival directions of the most energetic particles is shown. No interpretations of the data are offered