The assessment of the optimum harvesting stage is a prerequisite to evaluating the performance of new citrus genotypes. The intrinsic and extrinsic fruit quality traits of citrus fruits change ...throughout their developmental process; therefore, to ensure the highest quality, the fruit must be harvested at an appropriate stage of maturity. The biochemical changes in terms of total soluble solids (TSS), titratable acidity (TA), TSS/TA ratio, BrimA (Brix minus acidity), and ascorbic acid, in addition to the organoleptic acceptability of 16 new interspecific citrus hybrids, were evaluated in New Delhi (India) during the H1-H8 harvesting stage at 15-day intervals to standardize the optimum harvesting stage. The TA and ascorbic acid content were at a maximum level during the early harvesting stage and declined with time, reaching the minimum level in the last harvesting stage. The TSS, TSS/TA ratio, and BrimA values were found to have an increasing trend up to the last stage in most of the hybrids. The juice content shows an inclining trend during the initial harvesting observations, followed by stable juice content and then a decline. The BrimA was found to be a better predictor for consumer acceptability compared to the traditional maturity index TSS/TA ratio and, thus, harvesting maturity. Specific TSS, TA, and BrimA values, in addition to the juice percentage and ascorbic acid content, corresponding to the highest hedonic score, were judged as the optimum harvesting stage indicators for an individual hybrid genotype. Among the interspecific hybrids, SCSH-9-10/12, SCSH-11-15/12, and SCSH-17-19/13 were found to be superior, having better juice acceptability organoleptic scores (≥6.0) and higher juice content (≥40%). Principal component analysis based on fruit physico-chemical traits could be able to distinguish the optimum maturity stage in all of the citrus genotypes.
Tulipa suaveolens Roth is a decorative bulbous, polycarpic species in the Liliaceae family. Currently, the species populations are declining due to the degradation of natural steppes. In the present ...article, we evaluated the genetic diversity of 216 specimens from 22 natural T. suaveolens localities in the European part of the species range using 10 inter simple sequence repeat (ISSR) markers. The polymerase chain reaction (PCR) yielded 250 unambiguous and reproducible polymorphic bands with a mean polymorphism information content (PIC) value of 0.27. Neither the principal component analysis nor the clustering method split the dataset. However, the Bayesian model‐based STRUCTURE analysis detected two genetic clusters of T. suaveolens. The analysis of the biogeographical distributional pattern of the revealed genetic groups confirmed our hypothesis that the evolution and distribution of T. suaveolens were likely affected by the Early Khvalynian transgression of the Caspian Sea and the following Enotayevsk regression. Furthermore, this hypothesis was supported by the results of the NEW HYBRIDS analysis identifying the specimens from the populations located outside the Early Khvalynian flooding limit as pure parents, while the specimens of the populations within the flooding limit were classified as backcrosses and second generation hybrids.
Fruit juices of pigmented and non-pigmented new citrus hybrids obtained by crossing clementine cv. Oroval with different cultivars of blood oranges were analysed to determine parameters related to ...fruit quality (total soluble solids titratable acidity, pH), and the content of ascorbic acid, total phenolics, flavanones, anthocyanins and phenolic acids. Antioxidant properties were evaluated by oxygen radical absorbance capacity (ORAC), and inhibition of induced linoleic acid peroxidation (InLAP) assays. The results of this study show that some hybrids with high antioxidant activity owing to considerable polyphenol content may be considered rich sources of phytochemicals. The OTA 9 hybrid was shown to be richest in polyphenols, suggesting that consumption of OTA 9 fruit or juice could be useful in health promotion and a disease-preventing diet. Moreover, the juice of this hybrid could be used as raw material to produce antioxidant ingredients for dietary, pharmaceutical, or cosmetic purposes.
A new hybrid, Ophrys × armentariae, caused by crossing between Ophrys
passionis and Ophrys speculum, is described.
Se describe un nuevo híbrido dentro del género Ophrys, concretamente
el generado ...tras el cruce entre Ophrys passionis y Ophrys speculum. También
se discute la validez nomenclatural de los parentales.
'Zaoheibao' (a red tetraploid hybrid) and 'Wuhecuibao' (a white triploid hybrid) grapes have been obtained from Guibao ♀ (diploid, Vitis vinifera) x Zaomeigui ♂ (diploid, V. vinifera) and Guibao ♀ ...(diploid, V. vinifera) x Wuhebaijixin♂ (triploid, V. vinifera) respectively. Aroma characterisation of the two new table grape cultivars was firstly done by the investigation of volatile compounds. The influence of greenhouse cultivation and vintage on berry aroma was studied as well. The results showed that linalool, decanal, β-damascenone, hexanal and (E)-2-hexenal were the main volatile compounds of the two cultivars, which meant that the floral, fruity and sweet odour were prominent, followed by the herbaceous aroma. Greenhouse cultivation enhanced herbaceous odour in both 'Wuhecuibao' and 'Zaoheibao' berries, and reduced the floral aroma, contributed mainly by β-damascenone, in 'Wuhecuibao', and the sweet aroma, represented mainly by linalool, in 'Zaoheibao'. The concentrations of the main aroma compounds were greatly affected by vintage and the intensity of sensorial perception was correspondingly changed, but varietal odour attributes were not significantly altered. These results will not only help promote the cultivation and popularisation of these cultivars, but also will provide valuable data for the use of these cultivars in future breeding.
The response of dry matter accumulation and leaf photosynthesis in maize (
Zea mays L.) to low temperature has been documented during early phases of development, but little is known about the ...low-temperature response of maize during later phases of development. Studies were conducted in 1999 at the Cambridge Research Station, Ontario, Canada, to quantify the effect of low night temperature during grain filling on leaf photosynthesis of short-season maize hybrids. Plants were grown in a hydroponic system in the field with plants in the low-night temperature treatments exposed to 4°C from late afternoon (17:00
h) to the next morning (9:00
h). Plants of three maize hybrids (i.e., an older hybrid, Pride 5, and two more recent hybrids, Pioneer 3902 and Cargill 1877) were exposed to one night or three consecutive nights of 4°C at weekly intervals from tasseling to 6 weeks after silking. Carbon exchange rate (CER) was measured at 10:00, 12:00, 14:00, and 16:00
h on the second leaf above that subtending the topmost ear. Dark-adapted chlorophyll fluorescence (
F
v/
F
m) was measured at 9:00
h at 6 weeks after silking. Leaf CER of control plants declined almost linearly from about 50
μmol
m
−2
s
−1 at tasseling to about 20
μmol
m
−2
s
−1 at 6 weeks after silking with the rate of decline in the older hybrid approximately two times greater than that in the two newer hybrids. No trend in the reduction in cold-stressed leaf CER relative to the field-grown control was apparent from tasseling to 6 weeks after silking. Reduction in CER was greater during the morning than during the afternoon after exposure to 4°C and the reduction in leaf CER increased from 19.4% after one night, to 25.8% after two nights, and 30.2% after three nights. Mean reduction in leaf CER after one night at 4°C differed significantly among the three hybrids and was 29.7% for Pride 5, 15.4% for Pioneer 3902, and 13.5% for Cargill 1877. The reduction in leaf CER due to low night temperature was associated with a reduction in leaf chlorophyll fluorescence. In conclusion, maize hybrids differ significantly in leaf CER response to cold night temperature during the grain-filling period.
This study reports a new hybrid combination Ophrys × circlarium Pellegrino, hybr. nov., which derives from two highly divergent species, O. lutea (O. fusca-lutea complex) and O. tarentina (O. ...sphegodes complex). These two species grow sympatrically in the north of Calabria region (southern Italy), in a stand where two potential hybrid individuals were found during a floristic investigation. Two of the 16 morphometric characters analyzed were intermediate relative to those of the potential parental species. PCR-RFLP analysis of nuclear ribosomal DNA Internal Transcribed Spacer sequences (rDNA ITS) confirmed that the two specimens are hybrids of the two cooccurring Ophrys species.
