Grandis Cv Research Articles

Preliminary exploration of the plant culture of <italic>Torreya grandis</italic> in China

The conifer Torreya grandis is endemic to China and is a rare esculent species in the family Taxaceae. The plant culture of Torreya includes classification,food and medicine,landscape gardening,forestry,and related literature. The species was originally recorded on bamboo strips during the reign of the first emperor Qin Shi Huang. All the identifying features of the species have been described since the Ming Dynasty. The species was described scientifically in 1857. Torreya seeds have been used in herbal medicine since the Eastern Han Dynasty. More information on the potency of the species has been revealed since then. The use of the esculent torreya nut can be traced back to the middle of the Tang Dynasty. The cultivated variety,Chinese Torreya(T. grandis cv. Merrillii),was successfully cultivated by grafting. The West Zhejiang and South Anhui provinces are regarded as the origin of this variety. The selection of this species for landscape gardening began in the Western Han Dynasty. The conifer has even been planted in the Luoyang region,far from its natural source region in the Tang Dynasty. The use of the species in forestry can be traced back to the Song Dynasty. Its use reached its peak during the late Ming and the early Qing Dynasty in the Zhejiang and Anhui provinces. The appreciation of this species was encouraged by Su Shi,which led to Chinese torreya becoming fashionable during the Song Dynasty. Many poems were created about the conifer at this time.

Programmed cell death of secretory cavity cells in fruits of Citrus grandis cv. Tomentosa is associated with activation of caspase 3-like protease

Previously, we found that secretory cell degradation typically occurred through programmed cell death during secretory cavity development in Citrus sinensis L. (Osbeck). This finding indicated that secretory cavities could be utilized as a new cell biology model for investigating the regulatory mechanisms of plant programmed cell death. To study further the programmed cell death during secretory cavity development in Citrus fruit, we studied the morphogenetic characteristics of secretory cavities during their development in Citrus grandis cv. Tomentosa. Using light microscope- and electron microscope-TUNEL assays, immunohistochemistry and immunocytochemistry, we described the precise spatial and temporal alterations in caspase 3-like distribution, chromatin condensation and DNA fragmentation during the programmed cell death of secretory cavity cells. Caspase 3-like was found to be significantly located in both the cytoplasm and the nucleus of secretory cavity cells undergoing programmed cell death, and caspase 3-like is closely associated with chromatin condensation and DNA fragmentation. Interestingly, both caspase 3-like and DNA fragmentation were detected in the nucleoli. Our findings suggest that caspase 3-like may be involved in the programmed cell death of secretory cavity cells, especially in chromatin condensation, DNA fragmentation, nuclear degradation and the degradation of certain organelles.

Antioxidant Activity and Chemical Composition of Torreya grandis cv. Merrillii Seed

Torreya grandis cv. Merrillii is an endemic tree species in China, seeds of which are used as a popular snack, possessing beneficial effects on preventing angiosclerosis and coronary heart diseases. In this study, antioxidant activity and chemical constituents of T. grandis cv. Merrillii seed (TGMS) were investigated. The antioxidant activity of different fractions and the ethanol extract was evaluated using 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity, hydroxyl radical scavenging activity and lipid peroxidation assays. The oil, CH2Cl2 and n-BuOH fractions, and ethanol extract of TGMS all showed antioxidant activities in these models, especially the DPPH one. By GC-MS analysis, twenty-seven constituents were identified from the oil fraction of TGMS. The total content of phenolic compounds in the CH2Cl2 and n-BuOH fractions and ethanol extract was also determined by the Folin-Ciocalteau method as 17.6, 21.6 and 12.9 microg/mg, respectively. In addition, analysis of the CH2Cl2 fraction yielded four phenolic compounds: 4-hydroxybenzaldehyde, 4-methoxy pyrocatechol, coniferyl aldehyde, 4-hydroxy cinnamaldehyde, and two steroids, beta-sitosterol and daucosterol. These results provide scientific support for the empirical use of TGMS as a medicinal food for cardiovascular diseases.

Differential Reaction of Citrus Species in Malaysia to Huanglongbing (HLB) Disease using Grafting Method

Problem statement: Huanglongbing (HLB) is a phloem limited disease in citrus caused by a fastidious bacterium called 'Candidatus Liberibacter' found in Africa, Asia and United States of America (USA). HLB can severely reduce vigor and yield or kill all citrus trees within 5 years. There is a need to screen and identify suitable rootstock for propagation of clean plan materials for citrus in the tropics. This study was conducted to detect the presence of HLB on 18 selected citrus species and to categorize the level of infection and susceptibility of citrus species to HLB. Approach: Eighteen citrus species were assessed for susceptibility to HLB by graft transmission from source infection (Citrus reticulata). Results: HLB was detected in 15 species 6 months after grafting using PCR test. Conclusion: The species could be categorized in five groups: Severe group (72-58% severity) which includes C. reticulata, C. sinensis, C. reshni cv. cleopatra, moderate group (50- 41% severity) includes Fortunella sp. cv. Kasturi Chinai, C. macrophylla, C. microcarpa, mild group (25-17% severity) which included C. medica, C. aurantifolia, Citrus sp. (natural biotype), C. jambhiri. The tolerant group which did not show any HLB symptoms but tested positive by PCR test includes C. aurantium and C. aurantifolia. The resistant groups which include C. grandis cv. Limau Bali, C. hysterix and Citrus sp. cv. Limau Tembikai showed no symptoms and were tested negative for HLB.

Optimizing Culture System of Ri T-DNA Transformed Roots for Citrus grandis cv. Changshou Shatian You

Genetic transformation experiments of the different explants from Citrus grandis cv. Changshou Shatian You infected with Agrobacterium rhizogenes were carried out in darkness or in light. The optimizing culture system of Ri T-DNA transformed roots for C. grandis cv. Changshou Shatian You was constructed as follows: After the ventral wounded striations on the single activation cotyledon were inoculated by A. rhizogenes A4 (logarithmic period), they were cocultured at (25 ± 2)°C in darkness for 25–30 days; some transformed roots were generated from wounded striations of most cotyledons. The genetically transformed ratio is (83 ± 11)%. Axenic Ri T-DNA transformed roots (hairy roots) were harvested after five subcultures. Explants were activated on MT medium. The MS medium was used for subculture of transformed roots. Mass Ri T-DNA transformed roots in which the hormone was produced independently were harvested from this optimizing culture system. White, fresh Ri T-DNA transformed roots were (1.14 ± 0.07) cm long, (0.73 ± 0.04) mm wide, and the growth direction of transformed roots was negative geotropism.