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Maria C. Morera, Paul F. Monaghan, Michael D. Dukes, Ondine Wells and Stacia L. Davis

Over the last 10 years, Florida has repeatedly ranked as one of the nation’s largest users of groundwater ( Hutson et al., 2004 ; Kenny et al., 2009 ; Marella, 2014 ; Maupin et al., 2014 ). In 2006, three of the state’s five water management

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Shuiming Zhang, Zhongshan Gao, Changjie Xu, Kunsong Chen, Guoyun Wang, Jintu Zheng and Ting Lu

Chinese bayberry ( Myrica rubra Sieb. et Zucc., Myricaceae) is a subtropical evergreen fruit tree native to China and other Asian countries that bears delicious, juicy fruit rich in healthy compounds ( Chen et al., 2004 , 2008 ; Zhang et al

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D.C. Bowman and L. Macaulay

Comparative evapotranspiration (ET) rates of 20 cultivars of tall fescue (Festuca arundinacea Schreb.) were measured over 7 days in a greenhouse study. Small but significant differences in ET rates existed between the cultivars grown under nonlimiting water and nutrient conditions on day 1 following mowing. Greater differences had developed after 7 days of growth, with ET ranging from a low of 10.0 mm·day-1 for `Shortstop' to a high of 13.5 mm·day-1 for `Alta'. Day 7 ET was positively correlated (r = 0.82) with clipping dry weight. Six of the tall fescue cultivars were selected for a subsequent experiment to determine the stability of relative rankings for ET over time. Although average ET varied by up to a factor of two among five dates, the rankings were nearly identical for the five dates and were consistent with the rankings in the first experiment.

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Changling Zhao, Weiming Guo, Junyu Chen and Zhongchun Jiang*

Mei (Prunus mume Sieb. et Zucc.) flower is one of the candidates for the national flower of the People's Republic of China. Several major anthocyanins from the flowers of P. mume Sieb. et Zucc. were isolated with MeOH-HOAc-water (10:1:9, v/v), and purified by paper chromatography and subsequent column chromatography. Specific chemical reactions, chromatographic and spectroscopic analyses indicated that the anthocyanins in `Nanjing Hongxu' (Nanjing red-bearded) were cyanidin 3-O-(6'-O-α-rhamnopyranosyl-β-glucopyranoside) and cyanidin 3-O-(6'-O-galloyl-3'-O-β-glucopyranosyl-β-glucopyranoside). Anthocyanins in `Nanjing Hong' (Nanjing red) were cyanidin 3-O-(6'-O-α-rhamnopyranosyl-β-glucopyranoside), cyanidin 3-O-(6'-O-galloyl-β-glucopyranoside) and cyanidin 3-O-(6'-O-E-feruloyl-βglucopyranoside). In addition to contributing to the blue flower color, the anthocyanins may improve the ability of the two cultivars to survive at low temperatures.

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Takuya Tetsumura and Kensuke Yamashita

Japanese chestnut (Castanea crenata Sieb. et Zucc.) was micropropagated from nodal explants of 2-month-old seedlings, and the regenerated plantlets were acclimatized after potting. For in vitro establishment, 5 μm zeatin was more effective than 5 μm BA or TDZ, and Sato's (BW) medium was as effective as MS(½NO3) medium. Driver-Kuniyuki walnut medium produced more shoots showing hyperhydricity symptoms. In the multiplication culture, the higher the concentration of zeatin added to BW medium, the greater the number of shoots showing hyperhydricity, although the longest shoot was obtained when 6.9 μm zeatin was added. After planting in ½BW medium with 15 μm IBA for 5 d to induce rooting, shoots planted in ½BW medium plus vermiculite gelled with Gellan Gum (SV substrate) rooted better than those in either the gelled medium without vermiculite (S substrate) or vermiculite plus liquid medium (V substrate). One third of the shoots planted in the V substrate died, although 62% of the surviving shoots rooted well. Of the shoots planted in the S substrate, 83% survived, but only 35% of these survived rooting. Shoots rooted in the SV and V substrates survived well after the completion of acclimatization, and shoots rooted in the SV substrate grew more vigorously after potting. Chemical names used: 6-benzyladenine (BA); 6-(4-hydroxy-3-methyl-but-2-enylamino)purine (zeatin); indole-3-butyric acid (IBA); 1-phenyl-3-(1,2,3-thiadiazol-5-yl)urea (thidiazuron, TDZ).

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Fachun Guan, Shiping Wang, Rongqin Li, Mu Peng and Fanjuan Meng

rigorous conditions and inaccessibility of the Tibetan Plateau, few studies regarding the genetic diversity in plant populations have been conducted ( Guo et al., 2006 ). Prunus mira Koehne ( Prunus mira Koehne Kov et. Kpst) has been recognized as an

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J. Fang, Y. Qiao, Z. Zhang and C.T. Chao

We used amplified fragment length polymorphism (AFLP) markers to analyze 14 fruiting mei cultivars from China and Japan. The levels of polymorphism and genetic relationship among cultivars were studied using two types of AFLP primer combinations [EcoR I + Mse I (E+M) and EcoR I + Taq I (E+T)] and the combined data from both types of primer combinations (E+M+T). The polymorphism among the cultivars was 57.92% based on E+M primers and 63.04% based on E+T primers. All three dendrograms generated by the three sets of data showed similar relationships among the fruiting mei cultivars. The corresponding main clusters contained the same cultivars and the subgroups correlated closely with the known geographic origins of the cultivars.

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Li-ping Chen, Yan-ju Wang and Man Zhao

In this study, in vitro induction of tetraploid Lychnis senno Siebold et Zucc. and its cytological and morphological characterization were conducted. For polyploid induction, nodal segments with axillary buds from in vitro grown plants were kept for 3 days in MS (Murashige and Skoog, 1962) liquid or solid media added with a series of concentrations of colchicine. Out of total 588 recovered plants, 15 tetraploids and 6 mixoploids determined by flow cytometry analysis were obtained. The tetraploid contained 48 chromosomes, twice the normal diploid number of 24, as observed under light microscope. The tetraploid plants exhibited much larger but less stomata than diploid plants. Moreover, significant differences in stem height and leaf size between the diploid and tetraploid plants were noted. The tetraploid plants were more compact than diploids.

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Dariusz Swietlik

Several soil moisture measuring sensors are used to schedule irrigation of horticultural crops. However, without precise knowledge on root distribution, these devices may not provide accurate data on soil moisture conditions around the majority of roots. Also, some devices are expensive and/or require a tedious calibration and careful maintenance, limiting their use by growers. ET models have been successfully used for many crops grown in arid climates; however some models are not very precise and do not account for seasonal differences in plant water needs. Moreover, in humid regions it is difficult to assess the magnitude of rainfall contribution to the plant water needs particularly when only a part of the root system is irrigated. Research is needed to characterize plant variables which are useful for scheduling irrigation.

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Sung-Do Oh, Won-Seob Song and Man-Sang Lee

From one week through 7 weeks after artificial pollination, immature ovules of yooza(Citrus junos Sieb. et Tanaka) were excised and cultured in vitro on MT media. Even though there was only a little difference in percentage of somatic embryo formation depending upon the time of excision, immature ovules of 4-week-old showed the highest ratio of somatic embryo formation without callus outgrowth. Various growth regulators or other stimulators were added to the MT media to increase the somatic embryogenesis, In general, BAP was more effective than 2,4-D for somatic embryo formation and the combinations of 0.01mg/l 2,4-D and 0,01 or 0.1mg/l BAP were particularly effective in stimulating somatic embryo formation. When 500mg/l malt extract was added to the medium, the percentage of somatic embryo formation increased reaching as high as 86.7%. Plant regeneration from somatic embryos reached to 66.7% on the medium containing 1.0mg/l zeatin. Isozyme banding patterns were also analyzed to confirm the variations of characteristics of the plantlets derived from direct somatic embryos.