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Salt stress is a major constraint of crop productivity because it reduces yield and limits the expansion of agriculture. This study investigated salt tolerance in 26 cultivars of cut lilies (Lilium hybrids) by examining the effect of salt stress on the growth and morphological characteristics of flowers and leaves and their physiological properties (chlorophyll a fluorescence). Salt stress significantly affected the growth and development of cut lilies. Canonical discriminant analysis indicates that the middle leaf width, number of flowers, first flower diameter, petal width, and chlorophyll a fluorescence were correlated with salt stress, whereas plant height, the middle leaf length, days to flowering, and sepal width were less affected by the stress. The cultivars examined were divided into three groups: Group 1 included the salt-sensitive cultivars, which failed to develop normal flowers, Group 2 included cultivars sensitive to salt stress but tolerant to osmotic stress, and Group 3 was the salt-tolerant group, which developed commercially valuable flowers. In conclusion, the cultivars contained a variable range of cut flower characteristics and growth traits that can be employed for lily breeding programs and as material for molecular mechanisms and signaling networks under salt stress.

Freesia (Freesia hybrida Hort.) ‘Sweet Lemon’ was developed for the cut flowers in National Institute of Horticultural Herbal Science, Rural Development Administration, Korea in 2015. This hybrid was crossed and selected from ‘Teresa’ and ‘Yvonne’ in 2007. Morphological characteristics of the selected freesia hybrid were investigated for 5 years from 2009 to 2014, and then it was named ‘Sweet Lemon’ in 2015. ‘Sweet Lemon’ has double and lemon petals (RHS color chart Y2B). The average flower diameter was 6.8 cm and the average yield is 6.7. The growth of the plant is vigorous and the average plant height is 99.0cm, which is 34.7cm higher than the standard cultivar ‘Yvonne’. The average floret number per stalk of ‘Sweet Lemon’ was 10.7, and stalk length was 7.7 cm. The average days to first flowering of ‘Sweet Lemon’, 126 days, was approximately 20 days earlier than the control cultivar. It’s average vase life and yield is 8.7 days and 5.6 cormlets per plant, respectively. Totally 58 of volatile compounds were identified using gas chromatography-mass spectrometry (GC-MS), the major components were linalool, alpha-terpineol, alpha-selinene, and limonene.

Ranunculus asiaticus characterizes colorful and attractive flower shapes that are related with the ornamental value of bulbous plants. Improving ornamental value of bulbous flowers has been the general goal of floricultural market. Gibberellic acid (GA3) and benzyladenine (BA) play an important role in growth and developmental processes in floriculture. Combinational treatments of these two hormones have been used in floriculture to improve flower quality. We assessed the effects of combined GA3 and BA, as well as the individual effects of each hormone, on growth characteristics using soil drench application to eight R. asiaticus cultivars, ‘Giallo Millepetali’, ‘Bianco Millepetali’, ‘Arancio Millepetali’, ‘Rosa SC’, ‘Arancio Pratolino’, ‘Giallo Pratolino’, ‘Bianco Pratolino’, and ‘Rosa Ch Pratolino’. GA3 treatments increased plant height and first flower size of R. asiaticus cultivars. Moreover, about 5 to 9 days to flowering were averagely shortened by GA3 treatments compared to controls. On the other hand, the opposites, including first flower size and days to flowering, were observed for cultivars treated with BA, compared with controls. Treatments of GA3 + BA generally affected growth traits, such as plant height, flower size, and the timing of flowering on some R. asiaticus cultivars. In particular, about 5 to 6 days to flowering were reduced on average by Treatments of GA3 + BA. Our results showed positive growth effects, including plant height, days to flowering, first flower height, number of flowers from the application of individual and combined hormones to R. asiaticus cultivars and demonstrate a role for these hormones in future bulbous floriculture.

Scent is one of the most important economic traits in Freesia hybrida. &ldquo, Shiny Gold&rdquo, a popular cultivar in South Korea, is widely cultivated for its scent. The relative scent intensity of &ldquo, was approximately 16% higher in full-bloomed flower when compared to the yellow bud stage, while tissue-specifically, tepals showed higher intensity in electronic-nose (e-nose) analysis. E-nose analysis also showed that the scent intensity of &ldquo, was higher and lower than &ldquo, 10C3-424&rdquo, and &ldquo, 10C3-894&rdquo, respectively, and was similar to &ldquo, Yvonne&rdquo, These results correlated to those of the olfactory tests. In total, 19 volatile compounds, including linalool, &beta, ocimene, D-limonene, trans-&beta, ionone were detected in gas chromatography&ndash, mass spectrometry analysis. Among these, linalool was the major volatile compound, accounting for 38.7% in &ldquo, Linalool synthase and TPS gene expression corresponded to the scent intensity of the four cultivars, with the lowest expression in the &ldquo, TPS 2, TPS 3, TPS 5, TPS 6 and TPS 8 were highly expressed in both bud and flower in &ldquo, while the expression of TPS 4 was lower, relative to other TPS genes in both the flowering stages. These results may aid in enhancing scent composition in Freesia cultivars using marker-assisted selection.

Lily is an important cut-flower in Korea and world as well due to it’s a variety of flower colors and various sizes of flowers. To develop elite lily cultivars, conventional breeding techniques have been used so far. However, an introduction of tissue culture system in mass propagation of bulbs and regeneration of shoots with a high efficiency is prerequisite at this moment.Especially, growth of bulbs and shoots as well as reduction of browning is critical factor to proliferate bulbs with shoots of superior lines or cultivar in lily.For this purpose, we tried to test whether ascorbic acid, citric acid and silver nitrate in medium to facilitate growth of bulbs and shoots as well as reduction of browning of bulb scales in lily. As a result, ascorbic acid and silver nitrate showed no significant differences compared to control plants in the growth of bulbs and shoots. When bulb scales were treated with 150 mg ․l -1 of citric acid, formations of shoots and bulbs showed best result. While, bulb scale treated with 100 mg ․l

The effects of nutrient concentration and pH, two major chemical properties of soil, on plant responses were investigated with seedlings of tomato, which is widely grown in greenhouses, as the model plant. An experiment with four levels of nutrient concentration [None (NC 0), 1 (NC 1), 5 (NC 5), and 10 folds (NC 10)], in combination with three pH levels (4, 6, and 8), was conducted. The fresh and dry weight and leaf area of tomato seedling increased until NC5, but decreased at NC10. Transpiration rates, stomatal conductance, and evapotranspiration reduced with increasing nutrient concentration. The responses to the pH levels differed by the nutrient-concentration levels. The unsuitable root zone pH, pH 4 and pH 8, caused more reductions of transpiration rates, stomatal conductance, and evapotranspiration than pH 6 does under high nutrient concentrations, specifically pH 8 strongly depressed these. At pH 8, fresh and dry weight and areas of shoot and root sharply reduced more than at pH 4. Total nitrogen (...

This study was conducted to determine effects of soil pH and form of nitrogen fertilizers on tomato growth and chemical properties of greenhouse soil using ferigation system. Tomato (Lycopersicon esculentum Mill. cv. Superdoterang) were grown for three months in 18 L pots filled with two soil (pH 6.8 and pH 8.7). 4 different nitrogen fertilizers (urea, ammonium nitrate, ammonium sulfate, and potassium nitrate) were fertigated with different concentrations of 0, 10, 50, and 100 mg N/L during tomato cultivation. Soil pH 8.7 decreased yield and chlorophyll fluorescence compared with soil pH 6.8. Yield at soil pH 8.7 increased by ammonium nitrate and ammonium sulfate fertigation. Soil pH 6.8 induced increment of yield by nitrogen concentration than form of nitrogen fertilizers. Soil pH after cultivation of tomato decreased by application of ammonium nitrate and ammonium sulfate. Soil EC by 100 mg N/L application of ammonium sulfate was twice as much as other fertilizers. Form of nitrogen fertilizer had less effect on concentration of soil -N and -N in soil but the concentrations slightly reduced at pH 8.7. These results indicate that application of urea and ammonium nitrate for a nitrogen source of fertigation has little affects on soil chemical properties before and after tomato cultivation.

The thermotolerance and activation of antioxidant enzymes in the leaves of cucumber and tomato seedlings were induced by foliar application of H2O2. The induction of thermotolerance by foliar application of H2O2 was detected with decreased electrolyte leakage and malondialdehyde (MDA) content and increased water-soluble protein and chlorophyll content compared with heat-stressed seedlings. The levels of H2O2 and superoxide anions in the leaves of heat-stressed seedlings were also reduced by H2O2 pre-application before exposure to heat stress. The specific activities of ascorbic peroxidase (APX) and glucose-6-phosphate dehydrogenase (G6PDH) in the leaves of cucumber and tomato seedlings were significantly increased by foliar application of H2O2. The gel activities of superoxide dismutase (SOD), hydrogen peroxidase (HPX), and polyphenol oxidase (PPO) isozymes were abruptly increased by foliar application of H2O2 and these were maintained for 10 d afterward. The gel activities of guaiacol peroxidase (GPX) in the leaves of cucumber seedlings were significantly increased by foliar application of H2O2, but this did not occur in tomato leaves. Although one or two isoforms of SOD, HPX, and PPO isozymes in tomato leaves were suppressed by foliar application of H2O2, the total gel activities of the antioxidant enzymes were increased. These results suggest that foliar application of H2O2 before a crop is subjected to heat stress may be an effective and method to alleviate heat stress.