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1.
Plants (Basel) ; 13(12)2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38931044

RESUMO

Unraveling the intricate physiological and biochemical intricacies associated with female dominance in grape berries across diverse developmental stages is imperative for optimizing grape production and ensuring the attainment of high-quality yields. This study conducted a thorough analysis of grape berries across phenological stages (BBCH-79, BBCH-81, BBCH-89) and cultivars. At BBCH-89, Bozcaada Çavusu*Vasilâki demonstrated the highest berry weight and total soluble solids (TSS) levels, emphasizing its enological potential. Acidity peaked at BBCH-79 (28.16) and declined at BBCH-89 (6.11), signaling a shift towards lower acidity in later stages. Bozcaada Çavusu*Vasilâki consistently showed the highest maturity index (MI). Mineral content variations were observed across nitrogen (N), calcium (Ca), potassium (K), phosphorus (P), magnesium (Mg), sulfur (S), iron (Fe), manganese (Mn), boron (B), zinc (Zn), and copper (Cu), with Bozcaada Çavusu*Vasilâki often having the highest concentrations, particularly in potassium, calcium, and boron. Hormonal analysis revealed a significant surge in concentrations at BBCH-89, with Bozcaada Çavusu*Vasilâki standing out. Notably, Indole-3-acetic acid (IAA) concentrations increased by 106%, and abscisic acid (ABA) levels peaked at BBCH-79 with a 38% increase in Bozcaada Çavusu*Kuntra. Sugar content analysis showed variations in fructose, glucose, sucrose, rhamnose, xylose, galactose, and arabinose levels across sampling times and cultivars. Bozcaada Çavusu*Vasilâki consistently exhibited higher sugar levels, especially at BBCH-81 and BBCH-89. Vitamin concentrations varied temporally and among cultivars, with BBCH-89 displaying the highest vitamin A concentration (6.24 mg/100 g FW), and Bozcaada Çavusu*Vasilâki often exhibiting maximum values for vitamin B1, B2, B6, and C. Further research and targeted cultivation practices focusing on the unique attributes of Bozcaada Çavusu*Vasilâki could enhance grape production efficiency, emphasizing its potential contribution to achieving consistently high-quality yields across various phenological stages.

2.
Front Plant Sci ; 15: 1379328, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38828219

RESUMO

The dynamic fluctuations in autumn temperatures, particularly the marked diurnal variations and the subsequent precipitous drops are key and a pivotal role in viticulture, as they critically influence the acclimation process of grapevines to cold, thereby directly impacting their survival and productivity in cold-climate regions. In this comprehensive study, we investigated the cold hardiness of four grapevine cultivars: 'Itasca', 'Frontenac', 'La Crescent', and 'Marquette', focusing on how these cultivars and their individual buds (1st, 2nd, 3rd, 4th, 5th, 6th, 7th, 8th, and 9th) respond to fluctuating weather and low temperatures typical of autumn [-1.1°C (30°F) -9.4°C (15°F) and -17.8°C (0°F)]. Our results illuminated the striking variability in cold hardiness that was manifest not only among the different cultivars but also within individual buds on the same vine, underscoring the critical influence of bud position on a vine for cold hardiness. 'Frontenac' showed greater cold hardiness at critical temperatures at which 10%, and 50% of the dormant buds were lethally affected by cold (LT10 and LT50) compared to 'Itasca' and 'La Crescent', with 'Marquette' exhibiting intermediate values. However, in cultivars such as 'Itasca' and 'Marquette', certain buds demonstrated a pronounced hardiness when faced with colder temperatures, while others exhibited a heightened sensitivity, thereby revealing a nuanced interplay between bud position and a vine's ability to withstand cold stress. Our study revealed a notable divergence from traditional viticulture understanding; apical buds demonstrated greater cold hardiness than basal buds and opened new paths for research into grapevine physiology. Our results also indicated a significant trend wherein older vines across all studied cultivars displayed enhanced cold hardiness, particularly pronounced at the critical LT50 and the critical temperature at which 90% of the dormant buds were lethally affected by cold (LT90) thresholds, in comparison to younger vines. Moreover, our findings shed light on the impact of autumn's diurnal temperature variations and the subsequent drop in temperatures on vine cold hardiness, thus highlighted the complex interplay between environmental temperature dynamics and dormant bud hardiness. In conclusion, our study showed that the cold damage observed in grapevines in North Dakota was not a result of extreme temperature fluctuations in the fall. This was confirmed by testing the vines after they had reached various threshold temperatures through differential thermal analysis (DTA) and optical differential nucleation and expansion analysis (ODNEAL) methodologies, particularly before the onset of severe pre-winter cold conditions. These comprehensive findings highlighted the complexity of the vine's response to climatic conditions and viticultural management, pointing to the need for specific strategies in vineyard management and cultivar selection to optimize bud hardiness and productivity in the face of various environmental challenges, especially in cold climate viticulture.

3.
J Agric Food Chem ; 72(23): 12975-12987, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38807047

RESUMO

This study discovered the impact of high-tunnel (i.e., unheated greenhouse) and open-field production on two industrial hemp cultivars (SB1 and CJ2) over their yield parameters, cannabinoid development, and volatile profiles. Development of neutral cannabinoids (CBD, THC, and CBC), acidic cannabinoids (CBDA, THCA, and CBCA), and total cannabinoids during floral maturation were investigated. The volatile profiles of hemp flowers were holistically compared via HS-SPME-GC/MS. Findings indicated a high tunnel as an efficient practice for achieving greater total weight, stem number, and caliper, especially in the SB1 cultivar. Harvesting high-tunnel-grown SB1 cultivars during early flower maturation could obtain a high CBD yield while complying with THC regulations. Considering the volatile profiles, hemp flowers mainly consisted of mono- and sesquiterpenoids, as well as oxygenated mono- and sesquiterpenoids. Volatile analysis revealed the substantial impact of cultivars on the volatile profile compared to the production systems.


Assuntos
Canabinoides , Cannabis , Cromatografia Gasosa-Espectrometria de Massas , Inflorescência , Compostos Orgânicos Voláteis , Cannabis/química , Cannabis/crescimento & desenvolvimento , Cannabis/metabolismo , Canabinoides/análise , Canabinoides/metabolismo , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/metabolismo , Compostos Orgânicos Voláteis/análise , Inflorescência/química , Inflorescência/crescimento & desenvolvimento , Inflorescência/metabolismo , Flores/química , Flores/crescimento & desenvolvimento , Flores/metabolismo , Extratos Vegetais/química , Extratos Vegetais/metabolismo
4.
Front Plant Sci ; 15: 1321210, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38525141

RESUMO

Sugars and organic acids not only have a significant impact on taste balance and sensory acceptance by consumers but also play a crucial role in the chemical equilibrium of grape juices and wines. Therefore, this study aimed to quantify the content and composition of sugars and organic acids in 17 grape varieties over two consecutive years using high-performance liquid chromatography. The variability in all the parameters studied was strongly influenced by both the grape cultivars and specific years (p ≤ 0.05). In grape berries, the primary sugars identified were fructose and glucose, which ranged from 6.50 to 11.10 g/L and from 5.83 to 12.12 g/L, respectively, over the two years. However, sucrose was not detected in any of the grape varieties examined. For the two respective years, the highest titratable acidity (TA) was found in Tekirdag Çekirdeksizi (TeCe) (0.89 and 0.90 g/L), while the lowest was detected in Victoria (Vi) (0.48 and 0.51 g/L). Total soluble solids (TSS) peaked in Horoz Karasi (HoKA) (21.90 °Brix), whereas it reached its lowest point in Big Perlon (BiPe) (14.1 °Brix). The tartaric acid content in the grape berries, ranging from 1.48 to 10.33 g/L for the two years, exhibited similar characteristics to malic acid, which ranged from 1.09 to 9.62 g/L and from 1.03 to 9.68 g/L for the two respective years. The succinic, malic, tartaric, citric, and oxalic acid contents were notably higher in the Kyoho (Ky) variety than in the other varieties. When examining the dendrogram of the contents of organic acid and sugar for similarities, it was evident that 16 out of the 17 grape varieties had a high degree of similarity, except for Alphonse Lavallée (AlLa) and HoKa. The similarity levels among the varieties ranged from 99.49% to 72.36%. The highest similarity (99.49%) was observed between the AlLa and Baris (Ba) varieties. The lowest similarity was observed among the AlLa, HoKa, and Ky varieties. In summary, this study underscores that certain table grape varieties grown in Ankara exhibit significant variations in valuable organic acids and sugars, which are associated with potential health benefits when considering human consumption.

5.
Life (Basel) ; 14(2)2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38398687

RESUMO

A total of fourteen diverse, interspecific hybrid grapevines (Vitis spp.) were evaluated for their adaptability to North Dakota winter conditions using differential thermal analysis (DTA) of low-temperature exotherms (LTE) and bud cross-sectional assessment of survival techniques. This research was conducted in two vineyard locations in eastern North Dakota. This work demonstrates the use of DTA for monitoring and selecting cultivars capable of withstanding sub-zero temperatures. These results were assessed for quantitative genetic traits. High heritability was observed for bud LTE traits and may thus be a useful target for cold hardiness breeding programs; however, it is necessary to ensure that variance is reduced when pooling multiple sample events. After DTA sampling, grapevines were assessed for survival of primary and secondary dormant buds using cross-sectional visual evaluation of death. 'Valiant' had the greatest primary bud survival (68%), followed by 'Frontenac gris', 'Crimson Pearl', and 'King of the North'. These varieties are among those with potential for production in eastern North Dakota's environment. The newly evaluated relationships between traits and the heritability of DTA results provide valuable tools to grapevine breeders for the development of cold-tolerant genotypes for future climatic challenges.

6.
Plants (Basel) ; 11(12)2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35736712

RESUMO

In Egypt's arid and semi-arid lands where the main olive production zone is located, evapotranspiration is higher than rainfall during winter. Limited research has used nanomaterials, especially nano-silicon (nSi) to improve the growth, development, and productivity of drought-stressed fruit trees, amid the global water scarcity problem. To assess the role of nSi on drought-sensitive 'Kalamata' olive tree growth, and biochemical and physiological changes under drought conditions, a split-plot experiment was conducted in a randomized complete block design. The trees were foliar sprayed with nSi in the field using nine treatments (three replicates each) of 0, 150, and 200 mg·L-1 under different irrigation regimes (100, 90, and 80% irrigation water requirements 'IWR') during the 2020 and 2021 seasons. Drought negatively affected the trees, but both concentrations of nSi alleviated drought effects at reduced irrigation levels, compared to the non-stressed trees. Foliar spray of both concentrations of nSi at a moderate level (90% IWR) of drought resulted in improved yield and fruit weight and reduced fruit drop percentage, compared to 80% IWR. In addition, there were reduced levels of osmoprotectants such as proline, soluble sugars, and abscisic acid (ABA) with less membrane damage expressed as reduced levels of malondialdehyde (MDA), H2O2 and electrolyte leakage at 90% compared to 80% IWR. These results suggest that 'Kalamata' olive trees were severely stressed at 80% compared to 90% IWR, which was not surprising as it is classified as drought sensitive. Overall, the application of 200 mg·L-1 nSi was beneficial for the improvement of the mechanical resistance, growth, and productivity of moderately-stressed (90% IWR) 'Kalamata' olive trees under the Egyptian semi-arid conditions.

7.
J Sport Rehabil ; 28(1): 67-71, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-28952869

RESUMO

CONTEXT: Chronic plantarflexor (PF) stretching during ankle immobilization helps preserve calf girth, plantarflexion peak torque, and ankle dorsiflexion (DF) motion. Immobilization can lead to decreases in muscle peak torque, muscle size, and joint range of motion (ROM). Recurrent static stretching during a period of immobilization may reduce the extent of these losses. OBJECTIVE: To investigate the effects of chronic static stretching on PF peak torque, calf girth, and DF ROM after 2 weeks of ankle immobilization. DESIGN: Randomized controlled clinical trial. SETTING: Athletic training facility. PARTICIPANTS: A total of 36 healthy college-aged (19.81 [2.48]) females. INTERVENTIONS: Subjects were randomly assigned to one of 3 groups: control group, immobilized group (IM), and immobilized plus stretching (IM+S) group. Each group participated in a familiarization period, a pretest, and, 2 weeks later, a posttest. The IM group and IM+S group wore the Aircast Foam Pneumatic Walker for 2 weeks on the left leg. During this time, the IM+S group participated in a stretching program, which consisted of two 10-minute stretching procedures each day for the 14 days. MAIN OUTCOME MEASURES: One-way analysis of variance was used to determine differences in the change of ankle girth, PF peak torque, and DF ROM between groups with an α level of <.05. RESULTS: A significant difference was noted between groups in girth (F2,31 = 5.64, P = .01), DF ROM (F2,31 = 26.13, P < .001), and PF peak torque (F2,31 = 7.74, P = .002). Post hoc testing also showed a significance difference between change in calf girth of the control group compared with the IM group (P = .01) and a significant difference in change of peak torque in the IM+S group and the IM group (P = .001). Also, a significant difference was shown in DF ROM between the control group and IM+S group (P = .01), the control group and the IM group (P < .001), and the IM+S group and the IM group (P < .001). CONCLUSION: Chronic static stretching during 2 weeks of immobilization may decrease the loss of calf girth, ankle PF peak torque, and ankle DF ROM.

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