Showing papers in "Journal of Horticultural Science & Biotechnology in 1999"
TL;DR: Yields were higher in all the cultivars with irrigated treatments than in the rain-fed control, and during the season the relative water content in the leaves was higher in the irrigated treatment than inThe rain- fed control.
Abstract: SummaryThe aim of the present study was to evaluate the qualitative and quantitative yield response to irrigation of olive in southern Italy. The olive cvs Kalamata, Ascolana Tenera, and Nocellara del Belice were tested in a factorial combination with four irrigation levels: a rain-fed control (T0) and three treatments (T1, T2 and T3) irrigated daily with an amount of 33%, 66% and 100%, respectively of crop evapotranspiration. Soil water content remained near field capacity in treatment T3 with no difference with respect to treatment T2. In T0 and T1, the soil moisture decreased during the summer with the lowest value (20.8%) found in T0 on 12 August, after which rainfall restored the soil moisture to field capacity. During the season the relative water content in the leaves was higher in the irrigated treatments than in the rain-fed control. Yields were higher in all the cultivars with irrigated treatments than in the rain-fed control. The yield increase with treatment T1 in `Nocellara del Belice' was 20...
144 citations
TL;DR: An experiment on Regulated Deficit Irrigation (RDI) was performed in a ten year old, drip-irrigated `Clementina de Nules' mandarin orchard in Moncada, Spain during 1995 and 1996, with positive effects on yield and fruit quality.
Abstract: SummaryAn experiment on Regulated Deficit Irrigation (RDI) was performed during 1995 and 1996 in a ten year old, drip-irrigated `Clementina de Nules' mandarin orchard in Moncada, Spain. Treatments consisted of a control, where irrigation was applied without restriction during the whole year at 125% ETlys and RDI treatments where irrigation was reduced to 25% or to 50% of crop evapotranspiration measured by a weighing lysimeter (ETlys) during one of the following periods: I) flowering and fruit set (spring, 20 March to 3 July in 1995, and 1 April to 1 July in 1996); II) initial fruit enlargement phase (summer, 4 July to 7 August in 1995, and 2 to 28 July in 1996), and III) final fruit growth and maturation phases (end of summer–autumn, 8 August in 1995, and 29 July in 1996 to harvest). An additional treatment, denominated 50%–Year, was irrigated at 50% ETlys during the whole year. The effects of the treatments on yield and fruit quality in relation to tree water status (pre-dawn (ca) and midday (cmd) leaf ...
130 citations
TL;DR: Leaves of 22 accessions of olive from three named cultivars, and 17 accessions from cultivars with names that are suspected to include synonyms, showed a within-cultivar genetic similarity of at least 98% irrespective of source, while Verdale showed a high genetic variability, with some accessions having less than 80% similarity to others.
Abstract: SummaryLeaves of 22 accessions of olive (Olea europaea L.) from three named cultivars (Manzanillo, Kalamata, and Verdale), and 17 accessions from cultivars with names that are suspected to include synonyms (Corregiola, Corregiolo, Frantoio, Frantoja, Frantojol, Nevadillo, Nevadillo Blanco, and Picual) were obtained from Israel, Italy, the USA and Australia. Their genetic variability was investigated using random amplified polymorphic DNA (RAPD). Analysis of the PCR products was achieved by using the simple matching coefficient and UPGMA clustering. `Manzanillo' and `Kalamata' showed a within-cultivar genetic similarity of at least 98% irrespective of source. In contrast, `Verdale' showed a high genetic variability, with some accessions having less than 80% similarity to others. `Picual' and `Nevadillo' (including `Nevadillo Blanco'), which clustered at 69%, are possibly distinct cultivars. The identity of `Corregiola' and `Frantoio' and their synonyms is uncertain. Considering the extent of the genetic di...
95 citations
TL;DR: The results suggest that the improvement in fruit quality induced by the salinity is caused by the reduction of water import into the fruit.
Abstract: SummarySingle-truss tomato plants grown hydroponically (wet-sheet culture) were exposed to a salinity (EC) of 5.0 dS m21 or 8.0 dS m21 at two fruit ripening stages, the immature green stage and the decolouring stage. These salinities were achieved by adding NaCl to the standard solution, which had an EC of 2.4 dS m21. Increased salinity at the immature green stage improved fruit quality more than increased salinity at the decolouring stage but decreased fruit yield more. The reduction in fruit yield was due to a decrease in fruit weight but not in fruit number. Salinity increased the concentration of soluble solids, citrate, ascorbic acid, K, chlorophyll a, chlorophyll b, lycopene, and carotene in the fruit, but the absolute amount of these constituents per fruit was decreased or not affected. These results suggest that the improvement in fruit quality induced by the salinity is caused by the reduction of water import into the fruit. The effectiveness of both salinities was significantly bigger when it wa...
81 citations
TL;DR: Cut scapes of the four gerbera cvs Campitano, Dino, Sangria and Testarossa were preharvest sprayed and postharvest dipped or injected with 0, 0.5, 1.0, and 1.5% CaCl2 to study flower longevity and bending incidence.
Abstract: SummaryCut scapes of the four gerbera cvs Campitano, Dino, Sangria and Testarossa were preharvest sprayed and postharvest dipped or injected with 0 (control), 0.5, 1.0, and 1.5% CaCl2. Vase life and bending incidence were determined during storage at 258C. Scape calcium content was determined at the end of vase life. Significant extension of vase life and decrease in bending incidence was observed in blooms of `Campitano', `Dino' and `Testarossa' gerberas injected with 1.0% CaCl2, followed by dipping in 1.0% CaCl2 postharvest compared with the control. `Sangria' gerbera scapes preharvest sprayed with 1.0–1.5% CaCl2 had the longest flower longevity and the lowest bending incidence. Scape calcium concentration of `Campitano', `Sangria' and `Testarossa' increased by 250, 130 and 370%, respectively, compared with the control; calcium treatments resulted in a 3–4 d increase in vase life and a 3-5 d delay in bending incidence relative to the control; treatments with 1.5% CaCl2 considerably increased scape calci...
70 citations
TL;DR: The results showed that controlled water stress can substitute for pruning as a means of manipulating growth and enhancing final plant quality in Rhododendron.
Abstract: SummaryThe effect of restricting irrigation on shoot growth and flower initiation in container-grown Rhododendron cv. Hoppy was assessed. The results showed that controlled water stress can substitute for pruning as a means of manipulating growth and enhancing final plant quality in Rhododendron. Plants were exposed to three irrigation regimes based on potential evapo-transpiration (ETp) rates: 1.5 ETp (well-watered), 0.75 ETp (moderate drought), 0.25 ETp (severe drought), with regimes imposed for eight weeks during June–July, July–August, August-September or September– October. The degree and timing of drought had significant effects on the water status and growth of plants. Exposing plants to severe drought (0.25 ETp) during July–August inhibited shoot extension for the rest of the season, and plants remained small and compact until re-growth the following spring. Severe drought resulted in the initiation of fewer flower buds than less stressful regimes, especially when applied during the first two peri...
60 citations
TL;DR: In this article, the effect of glucosinolates on the control of soil-borne diseases was investigated in a more sustainable agriculture system, where the authors focused on the use of a sustainable food system.
Abstract: (1999). Towards a more sustainable agriculture system: The effect of glucosinolates on the control of soil-borne diseases. The Journal of Horticultural Science and Biotechnology: Vol. 74, No. 6, pp. 667-674.
55 citations
TL;DR: In this article, two levels of Ca21 (2 and 8 mM) were combined factorially with 2 levels of phosphate (0.2 and 1 mM) under two regimens of NaCl salinity (10 and 80 mM).
Abstract: SummaryMelon plants were grown hydroponically in a greenhouse to investigate the interaction of phosphorus and Ca21 under saline conditions on vegetative biomass production, yield and fruit quality. Two levels of Ca21 (2 and 8 mM) were combined factorially with two levels of phosphate (0.2 and 1 mM) under two regimens of NaCl salinity (10 and 80 mM). The increase of Ca21 concentration in the nutrient solution under saline conditions improved to the same extent vegetative growth and fruit yield. Parameters of fruit quality were affected by salinity, phosphorus and Ca21 nutrition. Salinity increased fruit quality by increasing firmness, total sugars and total soluble solids (TSS). High Ca21 treatment increased sucrose, fructose and glucose, this effect being greater under low salinity conditions than under high. In the two saline treatments, the highest concentration of sucrose in flesh was found at 0.2 mM of phosphate in the nutrient solution.
52 citations
TL;DR: In this paper, the relationship between peach fruit composition and growth was studied in six cultivar training-site-season combinations, including Prunus persica L. Batsch.
Abstract: The relationship between peach fruit (Prunus persica L. Batsch) composition and growth was studied in six cultivar-training-site-season combinations. Individual fruit growth and sugar and acid cont...
50 citations
TL;DR: The effects of pollen source on fruit set and fruit quality characteristics (xenia effects) were examined in three commercial cultivars of mandarin, Imperial, Ellenor, and Murcott, with significant xenia effects found in all cultivars.
Abstract: SummaryThe effects of pollen source on fruit set and fruit quality characteristics (xenia effects) were examined in three commercial cultivars of mandarin, Imperial, Ellenor, and Murcott. Six trees of each cultivar received six pollination treatments: three cross-pollen sources, self-pollination, bagging and bagging with emasculation. Pollen tube growth, percentage fruit set, fruit weight, seediness, sugar and acid content were assessed in all treatments. Significant xenia effects, including effects on sugar content, were found in all cultivars. `Imperial' was found to be self-incompatible as self-pollen tubes were inhibited in the upper style. This resulted in a lower fruit set in self-pollinated fruits (P<0.01), a very low fruit weight (33–55 g, compared with 92–103 g, P<0.01), and fruits containing few or no seeds. In addition, `Ellenor' and `Murcott' pollen significantly increased sugar content of fruit by between 0.9–1.6% compared with self-pollinated and unpollinated treatments (P<0.05). Widespread ...
49 citations
TL;DR: The results imply that the European cultivated gooseberry has a narrow genetic base and that further improvement to this crop species may require the introduction of additional germplasm into breeding programmes.
Abstract: SummaryRAPD, ISSR and AFLP markers were used to fingerprint and to examine genetic diversity among twelve genotypes of the gooseberry (Ribes grossularia subgenus Grossularia). AFLP generated unique profiles for each genotype. ISSR could not distinguish three of the genotypes, `Whinham's Industry' `Whitesmith' and `Leveller', whereas RAPD could not distinguish `Whinham's Industry' and `Leveller'. Similarity matrices and dendrograms illustrated the genetic similarities between the different genotypes but some clustering varied, depending on which marker type was being used. The results imply that the European cultivated gooseberry has a narrow genetic base and that further improvement to this crop species may require the introduction of additional germplasm into breeding programmes.
TL;DR: In this article, the browning of litchi fruit pericarp caused by water loss was investigated in relation to total phenolic concentration, phenylalanine ammonia-lyase (PAL) activity, reduced glutathione content, polyphenol oxidase (PPO) and peroxidases (POD) activities, and peroxide content.
Abstract: SummaryThe browning of litchi fruit pericarp caused by water loss was investigated in relation to total phenolic concentration, phenylalanine ammonia-lyase (PAL) activity, reduced glutathione content, polyphenol oxidase (PPO) and peroxidase (POD) activities, and peroxide content. Development of pericarp browning increased with reduced storage relative humidity (r.h.; from 90% to 60% r.h.) and increased storage time (from 1–3 d), and there was a strong time 2 r.h. interaction. Water loss from the pericarp increased PAL activity of pericarp of fruit stored at 60% or 70% r.h. with a maximum after 2 d storage, while activity of this enzyme stored at 80%, 90% or 95% r.h. remained at lower levels. Total phenolic compounds of litchi pericarp was initially high, and tended to decrease. Reduced glutathione content as an indicator of antioxidant capacities was lower for low storage r.h. values than for high ones, whereas a higher content of peroxides for lower storage r.h. was observed. PPO and POD activities of li...
TL;DR: Fruit grown under elevated temperatures during stage one had larger pedicels and dorsal vascular bundles, which suggests that temperatures during early fruit development determine the fruits' fruits' composition.
Abstract: SummaryThe growth and composition of satsuma mandarin fruit from trees which had been covered by a tunnel house during either stage one (the first ten weeks after anthesis), stage two (10±20 weeks after anthesis) or throughout fruit growth, were compared with those grown under ambient conditions. During each stage temperature was identified as the key factor influencing fruit development and changes to fruit were generally maintained when trees were returned to ambient conditions. Raising maximum air temperatures in the canopy of trees by 2.4.K during stage one increased both fruit growth rates and accumulation of sugars throughout their development. Titratable acidity levels were also increased and quinate levels decreased when trees were warmed during stage one, but these differences did not persist until harvest. Fruit grown under elevated temperatures during stage one had larger pedicels and dorsal vascular bundles, which suggests that temperatures during early fruit development determine the fruits' ...
TL;DR: The application of 3,5,6-TPA advances fruit maturation of peaches and nectarines through different mechanisms, depending on the fruit development stage at treatment, according to the climateric stage or pit hardening.
Abstract: SummaryThe application of 3,5,6-TPA advances fruit maturation of peaches and nectarines through different mechanisms, depending on the fruit development stage at treatment. Treatments applied at pit hardening encourage the development of fruit, which grow faster, reach the climateric stage earlier, and can be harvested earlier. The effect is direct, since the number of fruits per tree is not reduced by the treatment and also can be obtained by applying the auxin locally to a small number of fruits per tree. Treatments applied a few days before climateric increase ethylene production without affecting fruit growth.
TL;DR: In this paper, changes in antioxidant content (ascorbate and glutathione) and in the activity of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), total peroxidase (POX), ascorbate peroxideidase(APX), and GR remained stable.
Abstract: SummaryPears (Pyrus communis L. cv. Conference) were picked 7 d before (27 d), during (0) or 7 d (+7 d) after the estimated ideal time for commercial harvest. Changes in antioxidant content (ascorbate and glutathione) and in the activity of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), total peroxidase (POX), ascorbate peroxidase (APX) and glutathione reductase (GR) were estimated immediately after harvest for each picking time. Ascorbate and non-protein thiols (glutathione) content significantly decreased with increasing maturity. Concommitantly, the activity of SOD and CAT fell about five-fold and two-fold, respectively, when the fruit was picked more mature, indicating a higher potential for the accumulation of cytotoxic O2.2 and H2O2 respectively. POX activity remained relatively constant until the optimal harvest date but increased later. APX activity increased 2.5-fold in the more mature fruit but GR remained stable. Collectively, these results provide evidence that harvest dat...
TL;DR: In this paper, the authors investigated the relationship between delay in loss of firmness, and differences between activity of cell wall enzymes and pectin content of chilled and non-chilled fruits.
Abstract: SummaryMango (Mangifera indica L. cv. Nam Dokmai) fruits chilled for 21 d at 48C were firmer than non-chilled fruits during subsequent ripening at 258C. The cell wall contents of chilled fruit contained less water-soluble pectin, more ammonium oxalate-soluble pectin and less alkali-soluble pectin than non-chilled fruits. The increase in ammonium oxalate-soluble pectin was at the expense of the alkali-soluble pectin and correlated with high pectinesterase activity in the fruit from low-temperature storage. Polygalacturonase and b-galactosidase activities were inhibited in chilled fruits. The relationships between delay in loss of firmness, and differences between activity of cell wall enzymes and pectin content of chilled and non-chilled fruits are discussed.
TL;DR: Changes in carbohydrate content of inflorescent buds of fruiting and defruited branches of the same tree were measured in 1994 and 1995 in the period before and during bud abscission in pistachio to investigate its relationship to inflorescent bud ab scission.
Abstract: SummaryChanges in carbohydrate content of inflorescent buds of fruiting and defruited branches of the same tree were measured in 1994 and 1995 in the period before and during bud abscission in pistachio (Pistacia vera L. cv. Aegenes) to investigate its relationship to inflorescent bud abscission. HPLC was used for soluble sugar analysis, while starch was hydrolyzed to glucose enzymatically and the amount of glucose was then determined using the glucose oxidaseperoxidase method. The effect of fruit on leaf net photosynthesis (Pn), chlorophyll a and b (Chl (a+b)) in leaves and specific leaf weight (SLW) was also investigated in 1995. Starch concentration was initially similar in buds of fruiting and defruited branches but became greater in buds of defruited branches from early June 1994 (57 d after full bloom (AFB)) and 20 June 1995 (61 dAFB), resulting in higher starch contents. Glucose and fructose concentrations were similar in flower buds throughout the whole period of measurement; inositol and sucrose ...
TL;DR: It may be concluded that bumble bees are efficient pollinators as long as the flower organs are functional and a minimum number of pollen grains is available.
Abstract: SummaryThe efficiency of an electric bee in pollinating tomatoes grown in an unheated greenhouse was compared with that of bumble bees. Two years of experiments show that under the moderate climatic conditions of autumn and early winter, the two methods had similar effects on fruit set, seed number, fruit size and yield. Under more severe winter conditions, however, bumble bees were more efficient than the common agricultural practice of using the electric bee 2–3 times a week. Even in the presence of relatively low amounts of pollen grains per flower, a high percentage of fruit set was obtained by the bees. Under these adverse climatic conditions, flower vibration with the electric bee and with bumble bees achieved equal degrees of fruit set, only when the electric bee was operated every day. It may be concluded, therefore, that bumble bees are efficient pollinators as long as the flower organs are functional and a minimum number of pollen grains is available. For achieving similar pollination efficacy w...
TL;DR: The yield per plant was higher and fewer fruit were affected by BER in the treatment involving the higher level of irrigation, and the Ca concentration in the stylar portion of mature fruit was not significantly affected by the level of irrigation.
Abstract: SummaryAn experiment investigated the effects of two rates of irrigation, one of which reflected a substantial degree of water stress, on the mineral content, free amino acid levels and incidence of blossom-end rot (BER) in tomato (Lycopersicon esculentum Mill. `Durinta'). The plants were grown in the open with drip irrigation using saline water from a well (mean ECw 5.2 dS m21). The yield per plant was higher and fewer fruit were affected by BER in the treatment involving the higher level of irrigation. The fruit of the first and fifth truss, and the leaves immediately above, were analysed for their macronutrient, micronutrient and free amino acid content. The macronutrient leaf and fruit content hardly showed any difference, only the N concentration in fruit being significantly affected in the water stressed plants, in which the levels were higher. The Ca concentration in the stylar portion of mature fruit, which is related with the incidence of BER, was not significantly affected by the level of irriga...
TL;DR: In this article, apple plants were subjected to root temperature of 8.6.1 and 23.18C (LRT) and were irrigated with 100 ml of water containing 20 mg of N as NH4NO3, in which both ammonium and nitrate-N fractions were enriched in 15N (10 atom%).
Abstract: SummaryNon-bearing, potted, apple plants were subjected to root temperature of 8.6.1(LRT) or 23.6.18C (HRT) and irrigated with 100 ml of water containing 20 mg of N as NH4NO3, in which both ammonium and nitrate-N fractions were enriched in 15N (10 atom%). The root system of each plant was pressurized (325 kPa) at day 1, 2, 4, and 8 after15 N application to evaluate the transport of nitrogen derived from fertilizer (NDFF) through the xylem. This technique was used to investigate N absorption. LRT reduced the rate of N uptake the day after 15N application relative to HRT. Two, 4 and 8.d after fertilization, the rate of exudation and consequently the uptake rate was similar for LRT and HRT. The total amount of N removed by plants after 8.d was not affected by root treatments. Carbon dioxide assimilation, transpiration rate and stomatal conductance were lower for trees subjected to LRT during the time course of the experiment. We suggest that the delay in N absorption was related mostly to the lower activity ...
TL;DR: Experimental data of the transpiration and surface temperature of detached tomato fruits were collected to study and analyse how tomato fruit transpiration (E) was related to fruit character (F) in order to establish a causal relationship between fruit character and transpiration.
Abstract: Experimental data of the transpiration and surface temperature of detached tomato fruits were collected to study and analyse how tomato fruit transpiration (E) was related to fruit characteristics,...
TL;DR: All plants produced with water deficit were more compact than control plants and the cyclic-grown plants most closely resembled commercially produced plants.
Abstract: SummaryThe degree of drought tolerance exhibited by a plant is related to its ability to respond to adverse conditions. To determine if it is possible to alter this capacity in potted miniature roses (Rosa x hybrida), plants were produced with reduced water availability during the six weeks prior to flowering. The response of two rose cultivars to a cyclic non-lethal water deficit treatment (moderate water deficit with 5.d stress and 5.d recovery) and two long-term steady-state water deficit treatments at 60% (severe water deficit) and 75% (moderate water deficit) water availability, were compared. All plants produced with water deficit were more compact than control plants and the cyclic-grown plants most closely resembled commercially produced plants. Whilst all drought treatments significantly reduced the number of buds at flowering, time to flowering was not influenced by the treatments. Moderately stressed plants maintained leaf numbers but reduced the size of the individual leaves by 20%. In contras...
TL;DR: Higher contents of calcium and structural components viz. cellulose, hemicellulose and insoluble pectin were found in the pericarp cell walls of `Huaizhi', which might have materially contributed to its higherPericarp strength and thus cracking resistance as compared with `Nuomici'.
Abstract: SummaryTime-course changes of fruit cracking percentage, mechanical properties of pericarp and contents of cell wall components in litchi pericarp were studied by comparing two litchi cultivars differing in cracking susceptibility. Mechanical strength of the pericarp of crack-resistant cv. Huaizhi was greater than that of cracking-susceptible cv. Nuomici. The resistance of `Huaizhi' was also reflected in higher threshold cracking turgor as well as in higher pericarp tensile strength and extensibility. Correspondingly higher contents of calcium and structural components viz. cellulose, hemicellulose and insoluble pectin were found in the pericarp cell walls of `Huaizhi', which might have materially contributed to its higher pericarp strength and thus cracking resistance as compared with `Nuomici'.
TL;DR: The highest percentage of shoot formation and most shoots per responding explant were observed on florets taken from stage II flower heads, and direct shoot formation was confirmed by scanning electron microscopy and histological observations.
Abstract: SummaryThe main bottleneck of mutation induction in vegetatively propagated ornamentals is the development of chimera. Ephemeral small sectors apparent on petals cannot generally be recovered as solid mutant shoots. An efficient technique has been standardized in the present experiment for direct shoot regeneration from individual florets of...chrysanthemum (Chrysanthemum morifolium Ramat.) cv. Colchi Bahar. The efficiency of direct shoot regeneration was tested on 16 media based on MS basal medium containing sucrose, agar and different concentrations and combinations of BAP and NAA. The regenerative potential varied with the developmental stages of the flower head. The highest percentage of shoot formation and most shoots per responding explant were observed on florets taken from stage II flower heads. Direct shoot formation was confirmed by scanning electron microscopy and histological observations. The technique has been tested on 16 other cultivars in the medium containing 0.2 mg l21 NAA and 1.mg.l1 B...
TL;DR: A positive correlation between nitrate content and nitrogen application rate was found and a reduced contribution of nitrate to sap osmotic potential at the higher light level was accompanied by a significant increase in the contribution of sucrose.
Abstract: SummaryThe effect of nitrogen availability and low level supplementary light on the growth and nitrate content of butterhead lettuce (Lactuca sativa var. capitata L.) grown in soil under greenhouse conditions in winter was studied. No significant interactions between nitrogen availability and supplementary light on yield, nitrate content, osmotic potential of expressed leaf sap and component osmotica were found. Supplementary light greatly increased plant growth and resulted in earlier harvest. When harvested with similar fresh weights, plant nitrate content was significantly reduced by supplementary light although the effect was slight. The reduced contribution of nitrate to sap osmotic potential at the higher light level was accompanied by a significant increase in the contribution of sucrose. While plant fresh weight was unaffected by the rate of nitrogen application, a positive correlation between nitrate content and nitrogen application rate was found. Reduced nitrate content at low nitrogen applicat...
TL;DR: In this paper, the role of fruit expansion and turgor in the formation of cuticular cracking in bell pepper (Capsicum annuum L) was studied and it was shown that when isotonic mannitol solution was used, cracking did not occur.
Abstract: SummaryThe objective of this research was to study the role of fruit expansion and turgor in the formation of cuticular cracking in bell pepper (Capsicum annuum L.). Fruit was artificially cracked by filling detached hollowed pepper fruits with distilled water. However, when isotonic mannitol solution was used, cracking did not occur. Similarly, immersion of intact red fruits in tap water caused formation of cuticular cracks following a delay of 30 h during which the turgor potential of the red pericarp and the expansion of the fruit diameter increased to critical threshold values of 0.65 MPa and 1±2%, respectively. On the other hand, in the greenhouse, attached red fruits underwent diameter change of only 0.2% and, when most expanded, the fruit had a turgor potential of only 0.3 MPa. In greenhouse grown plants, pepper fruits become susceptible to cracking at the stage of colour turning, a stage at which they also become susceptible to artificially induced cracking by immersion in water. Under greenhouse ...
TL;DR: Thidiazuron (TDZ) remarkably increased fruit growth soon after application and tended to decrease the fruit length/average diameter ratio, especially at the higher concen...
Abstract: SummaryThe effects of thidiazuron (TDZ) on growth, quality and ripening of kiwifruits were evaluated by comparison with untreated (control) and CPPU (cytokinin) treated fruits. Two weeks after full bloom (AFB), TDZ at 5, 10 or 20 ppm and CPPU at 20 ppm were applied to fruits by dipping them for about 5.s in aqueous solutions of the two compounds. TDZ remarkably increased fruit growth soon after application. The increase in size levelled off at 10 ppm and no further improvement in fruit size resulted from the 20 ppm treatment. At harvest, TDZ treated fruits, depending on the concentration, were 50% or 60% heavier than untreated ones. All TDZ concentrations used also gave a large (+44%) and similar increase in fruit dry weight. TDZ did not cause significant variations in the number and weight of seeds. TDZ caused some modification in fruit shape. It increased the percentage of fruits having a protruded distal end and tended to decrease the fruit length/average diameter ratio, especially at the higher concen...
TL;DR: In two consecutive seasons, it was found that the rate of fruit-set and fruit yield were significantly higher in the rows of `Topred' adjacent to the `Golden Delicious' as compared with the rows adjacent tothe `Jonathan'.
Abstract: Summary`Topred' is one of the main apple cultivars in Israel. Since `Topred' exhibits full self incompatibility, its fruit production is totally dependent on cross pollination. The two commercial pollenizers of `Topred' in Israel are `Golden Delicious' and `Jonathan'. In the study presented here, the potential of these two pollenizers was determined. In two consecutive seasons, it was found that the rate of fruit-set and fruit yield were significantly higher in the rows of `Topred' adjacent to the `Golden Delicious' as compared with the rows adjacent to the `Jonathan'. PCR analysis of the S-alleles, a polymorphic gene locus, determining the outcome of pollination, revealed that `Jonathan' and `Topred' share allele S9. PCR-S-allele analysis of progeny seedlings revealed that in `Jonathan' only S7, the unshared allele, took part in fertilization, whereas both alleles of `Golden Delicious' (S2,S3) participated at equal rates. Thus, the lower potency of `Jonathan' as a pollenizer of `Topred' is due, at least ...
TL;DR: A judicial trial offered a unique opportunity to develop an innovative line of research for molecularly characterizing Pelargonium peltatum genotypes on the basis of RAPD and AFLP fingerprinting.
Abstract: SummaryPelargoniums are of considerable commercial importance, mainly because they are highly decorative and relatively easy to cultivate. As the numbers of pelargonium cultivars are continuously increasing, the adoption of reliable and discriminant molecular tools capable of identifying new cultivars and determining their diversity with respect to already registered ones promises to be the prime requirement for a valuable decorative plant market, as well as a genetic guarantee of the value of plant materials. A judicial trial offered a unique opportunity to develop an innovative line of research for molecularly characterizing Pelargonium peltatum genotypes on the basis of RAPD and AFLP fingerprinting. The DNA polymorphism of a pelargonium flower recovered at the site of a crime was compared with those of nine plants seized in the house of the suspected murderer. Once an efficient protocol for isolating genomic DNA in pelargonium had been optimized, a total of 162 RAPD and 568 AFLP markers were detected u...
TL;DR: The results show that at night pepper plants transpired at a rate proportional to the vapour pressure difference (leaves to air; VDPla) in the respective greenhouses, and the percentage of cracked fruits was highest in the greenhouse with the lowest night vapours pressure deficit (VPD) and lowest in the greenhouses with the highest VPD.
Abstract: SummaryThe cracking of bell pepper fruit is one of the main physiological disorders that reduce marketable yield. Understanding the environmental and endogenous factors that influence this disorder may help to reduce its severity. Plants grown in three greenhouses were subjected to differing potential transpiration (Tp) at night, with identical daytime Tp. Measurements included climatic variables in the greenhouses, soil water content, sap flow, transpiration, leaf temperature, surface and internal fruit temperatures, fruit and stem diameters, stomatal conductance, and leaf area. The results show that at night pepper plants transpired at a rate proportional to the vapour pressure difference (leaves to air; VDPla) in the respective greenhouses. The percentage of cracked fruits was highest in the greenhouse with the lowest night vapour pressure deficit (VPD) and lowest in the greenhouse with the highest VPD. Both increased direct radiation reaching the fruit surface and decreased soil water content reduced ...