Showing papers in "Journal of Horticultural Science & Biotechnology in 2001"
TL;DR: In this paper, the combined effect of increasing concentrations of NaCl in the irrigation water and fertilization with different nitrogen sources on the chemical composition of tomato (Lycopersicon esculentum mill.) fruit was investigated.
Abstract: SummaryThe combined effect of increasing concentrations of NaCl in the irrigation water and fertilization with different nitrogen sources on the chemical composition of tomato (Lycopersicon esculentum Mill.) fruit was investigated. Increasing water salinity from 0.5.dS m-1 (non-salinized control) to 15.7.dS m-1 resulted in both reduced fruit size and fruit water content, whereas it caused an increase in soluble solids, carbohydrates, sodium and chloride concentrations. Titratable acidity increased upon irrigation with saline water, whereas the fruit redness significantly decreased. In addition, salinity reduced P, K+, Mg2+ and NO3- fruit concentrations. Total carotenoids and lycopene concentrations expressed on both fresh- and dry-weight basis gradually increased from the non-salinized control to the 4.4.dS m-1 treatment (approximately 0.25% NaCl w/v) and they decreased at electrical conductivities of the irrigation water higher than 4.4.dS m-1. Overall these data show that it is possible to improve carot...
241 citations
TL;DR: In this article, the authors studied the possibility to manipulate the nature of the vegetative growth of greens to improve the yield and quality desirable for various ornamental crops, including green decorative branches.
Abstract: SummaryMany green decorative branches (“greens”), which form an important part of ornamental bouquets, originatefrom shade plants, and are commercially grown in Israel under black shade nets. We are studying the possibility to manipulate the nature of the vegetative growth of greens to improve the yield and quality desirable for various ornamental crops.The present paper summarizes the results obtained for Pittosporum variegatum grown under shade nets of various optical properties: green, red, blue, grey, black, and reflective. The knitting density and design of the nets were adjusted to give the same transmittance of sunlight in the PAR (photosynthetically active radiation, 400–700.nm) region. The experiments were carried out in a commercial plot. A single layer of 50% shade net covered the plot during thewinter season, and two layers in the summer, according to common practice. Data were collected mostly during the second growth year. The main results obtained included: (i) pronounced stimulation of bra...
170 citations
TL;DR: Together, solarization and grafting provided complete protection from all three diseases, and had an additive effect on yield, resulting in a significant increase over that obtained by either method alone.
Abstract: SummarySoil solarization and grafting onto a resistant tomato rootstock (‘Brigeor F1‘), and the integrated use of both methods were evaluated in four field trials carried out in Cyprus, for management of soil-borne pathogens and pests of eggplant. Soil solarization was highly effective against Verticillium wilt (V. dahliae) but only partially effective against corky root rot (Pyrenochaeta lycopersici) and root-knot nematodes (Meloidogyne spp.); it also controlled adequately most annual weeds. By contrast, grafting provided complete protection from corky root rot and root-knot, but only partial protection from Verticillium wilt. Complete resistance to nematodes, however, occurred only in trials with greenhouse-grown (winter) crops. In open-field (summer) crops, about 50% of the grafted plants sustained slight nematode infection, apparently because of breakdown of resistance at high soil temperatures. Solarization, or grafting gave significant yield increases over that of the untreated check. However, a com...
84 citations
TL;DR: In muskmelon, interestingly, seedling growth was increased by both walnut leaf extracts and juglone, and positive correlation was found between the effects of jugl one and the extracts.
Abstract: SummaryThe allelopathic effects of juglone and leaf extracts of walnut (Juglans regia L.) on seed germination and seedling growth of 11 species were investigated. Seed germination was less affected than root and shoot growth in all species. Both seed germination and seedling growth of tomato, cucumber, garden cress and alfalfa were inhibited strongly by the treatments. However, seed germination of wheat, barley, corn, watermelon, radish and bean was not affected but their seedling growth was inhibited slightly. In muskmelon, interestingly, seedling growth was increased by both walnut leaf extracts and juglone. Positive correlation was found between the effects of juglone and the extracts.
82 citations
TL;DR: The aim of this study was to find a photoperiod treatment that induces flowering but does not reduce vegetative growth in strawberry ‘Korona’.
Abstract: SummaryIn Junebearing strawberry cultivars, flowering is induced by short photoperiod, which also reduces vegetative growth. The loss in vigour can lower yield if plants are not cold treated to restore vegetative growth. The aim of this study was to find a photoperiod treatment that induces flowering but does not reduce vegetative growth in strawberry ‘Korona’. Plants were subjected to different photoperiods (12, 13.5 or 15.h) for varying durations (21, 35 or 49.d). After treatments, effects on plant development were recorded during forcing at 18 h daylength. Floral induction was comparably successful in 12 and 13.5.h photoperiods and the number of flowers and yield were increased by lengthening the treatment. Induction failed in many plants treated in a 15.h photoperiod and flowering was poor regardless of duration of treatment. Shorter photoperiod increased the number of branch crowns and reduced runner production, and these effects were enhanced by lengthening the treatment duration. Reduction in veget...
67 citations
TL;DR: In this article, a gradual reduction of irrigation during a three-week period followed by a 17 d recovery was applied to field-grown (SF) and lysimeter-grown trees.
Abstract: SummaryContinuous monitoring of trunk diameter and of sap flow were investigated to evaluate and characterize tree responses to irrigation water deficits in peach trees (Prunus persica (L.) Batsch ‘O’ Henry’). A gradual reduction of irrigation during a three-week period followed by a 17 d recovery was applied to field-grown (SF) and lysimeter-grown (SL) trees. Trunk-diameter change (TDC) measurements and maximum daily trunk shrinkage (MDS) were compared with predawn leaf water potential (PLWP) and midday stem water potential (SWP). TDC was also compared with sap flow calibrated in a weighing lysimeter. The experimental calibration of sap flow (r = 0.95) in a lysimeter showed a 45% underestimation of tree transpiration with a coefficient of 0.55, similar to values found in other tree species. The reductions of water supply were reflected clearly by MDS which showed differences among treatments after only 4 d of 75% ET application. MDS was closely related to PLWP and to midday SWP in both deficit irrigation...
65 citations
TL;DR: It seems that a large number of foragers per tree directly increases the amount of pollination, high bee mobility between rows increases the amounts of cross-pollination, and a high proportion of “topworkers” increases pollination efficiency.
Abstract: SummaryThe ‘Red Delicious’ apple exhibits full self-incompatibility, therefore its fruit production depends totally on cross pollination, especially by honeybees, which are the ultimate apple pollinators. In the present study, the technique of sequential introduction of honeybee colonies and doubling their density was applied to determine effects on yield. In three consecutive season it was found that sequentially increasing the density of colonies in the apple orchards from 2.5 colonies per ha., as recommended previously, to 5.0 colonies per ha, and introducing them sequentially (half at the 10% full bloom (FB) and half at FB), increased the number of bees per tree, their mobility among the rows, and the proportion of “topworkers” compared with “sideworkers” . It seems that a large number of foragers per tree directly increases the amount of pollination, high bee mobility between rows increases the amount of cross-pollination, and a high proportion of “topworkers” increases pollination efficiency. All th...
60 citations
TL;DR: This anatomical investigation on olive secondary somatic embryos describes several aspects of embryo development, including proembryoid origin and growth, aspects of tissue differentiation, localization of somatic embryogensis, and starch occurrence.
Abstract: SummaryThis anatomical investigation on olive secondary somatic embryos describes several aspects of embryo development, including proembryoid origin and growth, aspects of tissue differentiation, localization of somatic embryogensis, and starch occurrence. The failure of a number of secondary somatic embryos to develop into perfect structures is to be ascribed to defects in the last growth stages (fused embryos, fused cotyledons) and/or to tissue degeneration processes affecting both imperfect and apparently perfect somatic embryos.
55 citations
TL;DR: RAPD (random amplified polymorphic DNA) markers were used to determine genetic diversity within and between populations of cashew (Anacardium occidentale L.), with accessions from Brazil being the most distinct from the other provenances.
Abstract: SummaryRAPD (random amplified polymorphic DNA) markers were used to determine genetic diversity within and between populations of cashew (Anacardium occidentale L.). Efficient and novel procedures for extracting PCR-amplifiable, high molecular weight DNA from young cashew leaves were developed and the PCR conditions for RAPD analysis of cashew DNA using random 10.bp primers were defined. Optimized PCR-reaction conditions were then used to analyse differences in RAPD profiles within and between a selection of cashew varieties obtained from diverse geographical locations around the world and within a pool of twenty elite Tanazanian cashew lines. RAPD polymorphisms were obtained among the Tanzanian lines and between and within the geographically diverse lines. The relatively uniform RAPD profiles for the selection of random primers tested suggested a high degree of DNA level similarity between the Tanzanian accessions. Accessions from India, Mozambique and Tanzania showed the closest relationship, with acces...
54 citations
TL;DR: Marker assisted selection may greatly facilitate pistachio rootstock breeding as well as cultivar improvement, because of the long juvenile period of Pistacia species, and segregating populations from controlled crosses are required to elucidate such mechanism.
Abstract: SummaryMarker assisted selection may greatly facilitate pistachio rootstock breeding as well as cultivar improvement, because of the long juvenile period of Pistacia species. Early diagnosis of seedling sex type would assist breeding and nurserymanagement in these dioecious species. We searched for RAPD markers linked to sex in P. atlantica, P. terebinthus and P. eurycarpa, the main wild species in Turkey that are used as rootstocks for P. vera. For this purpose, leaf samples were collected from male and female individual trees from each species and sex-pooled DNA samples were prepared by mixing the DNA of ten male and ten female individuals, to screen for sex associated RAPD bands. A total of 472 primers have been screened so far and two bands, amplified by primers BC156 and BC360, appeared to be sex assocaited in P. eurycarpa. The bands were tested in 30 male and 37 female individuals. Band BC156 (1300) was present in all, except one, female trees and was absent from all the male trees. Band BC360 (500)...
52 citations
TL;DR: An efficient protocol for micropropagation of Rosa damascena Mill has been established using single node segments from mature bushes using thidiazuron and a short treatment with IBA was found to be very effective for root induction.
Abstract: SummaryAn efficient protocol for micropropagation of Rosa damascena Mill. has been established using single node segments from mature bushes. The effect of thidiazuron has been compared with that of N6-benzyladenine (BA) on in vitro shoot proliferation. The cultures initiated on medium supplemented with thidiazuron (TDZ) and/or cultured continuously on TDZ containing medium for 32–48 weeks exhibited considerably more shoot proliferation and growth during subsequent culture on a medium containing BA. Shoots induced on TDZ containing medium and then sub-cultured (8–12 times) on medium containing BA, attained the capacity to grow and proliferate on a medium free from plant growth regulators (PGR). Microshoots from TDZ induced cultures could be rooted easily on indole-3-butyric acid (IBA) supplemented medium. A short treatment with IBA (100 mM; 12 h) was found to be very effective for root induction. The rooted plants were successfully transferred to pots after 15 d of hardening in a mist chamber with about 7...
TL;DR: The regime involving least water and lowest temperature in the nursery period produced plants best adapted to stress at transplanting: a greater root length:shoot length ratio, higher percentage of brown roots and lower fresh weight:length ratio in shoots.
Abstract: SummaryThe influence of irrigation and temperature regimes in the nursery on the dynamics of root development after being transplanted with minimum management conditions was investigated in Lotus creticus. In the nursery period (three months), plants were pot-grown in greenhouses, heated and unheated, located on the Southeast Mediterranean coast of Spain. Drip irrigation was used, with three irrigation treatments: T-6, plants watered 6.d a week at the water-holding capacity; T-3, plants watered 3.d a week; and T-2, plants watered twice a week. The total water applied over the whole nursery period was (in litres per plant): T-6, 7; T-3, 3.5; and T-2, 2.3. After the nursery period, plants were transplanted in a growth chamber into transparent containers (round acrylic tubes 8.cm diameter and 100.cm tall) and just one establishment irrigation was applied. Three treatments were applied, using three different amounts of water in the establishment irrigation: 10, 30 and 60.mm. The containers were kept in the gr...
TL;DR: P. cerasus selections seem to be the best adapted rootstocks for cherry cultivars in heavy and calcareous soil conditions, under flood irrigation, however, they had the highest number of root suckers.
Abstract: SummaryThe field performance of CAB 6P, CAB 11E, ‘Colt’, GM 9 ('Inmil'), GM 61/1 (‘Damil’), GM 79 (‘Camil’), Masto de MontanAana 9 (MM 9), MaxMa 14, MaxMa 97 and Sainte Lucie GF 64 (SL 64) rootstocks grafted with one sweet cherry cultivar (P. avium ‘Sunburst’), were compared for the first nine years after planting. The orchard was located on a calcareous clay-loam soil, which was level-basin irrigated. While no trees of CAB 6P, ‘Colt’, ‘Damil’, MM 9, and MaxMa 97 rootstocks died, most of the trees on ‘Inmil’ and ‘Camil’ did die. ‘Damil’ proved to be the most dwarfing and low-yielding rootstock, whilst ‘Colt’, MM 9 and CAB 6P were the most invigorating rootstocks, although differences with CAB 11E and SL 64 by the ninth year after planting were not significant. An intermediate level of vigour, shown on MaxMa rootstocks, could indicate a semi-dwarfing potential for these selections. In general, P. cerasus rootstocks (CAB 6P, CAB 11E and MM 9) promoted greater cumulative yields and better yield efficiency th...
TL;DR: Traditional pear cultivars in Xinjiang were evaluated using RAPD markers and compared with representatives of Occidental pear species, cultivars of P. communis and East Asian pear accessions to confirm that P. sinkiangensis is of hybrid origin and at least P. armeniacaefolia and Chinese white pears or sand pears have been involved.
Abstract: SummaryThirteen native pear species have been identified in China, of which P. armeniacaefolia Yu and P. sinkiangensis Yu are specific to Xinjiang. P. armeniacaefolia grows wild and a few cultivars have been assigned to this species. Cultivars of P. sinkiangensis have been suspected to be of hybrid origin involving P. communis L. and P. bretschneideri Rehd. In this study, traditional pear cultivars in Xinjiang were evaluated using RAPD markers and compared with representatives of Occidental pear species, cultivars of P. communis and East Asian pear accessions. The combination of 72 pear accessions and 20 selected primers produced 231 scorable polymorphic RAPD bands, of which some were specific to certain species. Five main groups of pear accessions could be distinguished from UPGMA analysis: 1) P. xerophila Yu, its relatives and one cultivar of P. ussuriensis Max., 2) cultivars of P. sinkiangensis, 3) cultivars of P. pyrifolia Nakai and P. bretschneideri, 4) wild Occidental species, cultivars of P. commun...
TL;DR: The findings demonstrate the effectiveness of CPPU in these pear cultivars and show that it has a significant potential to improve cropping, without any negative aspects.
Abstract: SummaryThe effects of the synthetic cytokinin CPPU, derived from phenylurea, on fruit size and yield of the small-fruited, low-chilling requiring ‘Spadona’ and ‘Costia’ pears, were examined in Israel. CPPU caused appreciable increases in fruit size of both cultivars, when applied at 10–20 ppm, two weeks after full bloom, whereas application after four weeks gave only small effects or none. The effect of CPPU on fruit growth was already evident two months after application, when the fruits reached 35–40 mm in diameter. The large increase in fruit size occurred without thinning and, therefore it must be attributed directly to the effect of CPPU. CPPU increased fruit size with no influence on fruit shape, seed number and it did not reduce return bloom in the following spring. A semi-commercial application of 10 ppm CPPU increased fruit size by 40% in ‘Spadona’ and 80% in ‘Costia’ with an increase of about 50% in the total yield of each cultivar. Our findings demonstrate the effectiveness of CPPU in these pea...
TL;DR: Rooted cuttings of Dendranthema grandiflora Tzvelev.
Abstract: SummaryRooted cuttings of Dendranthema grandiflora Tzvelev., Nerium oleander L. and Lantana camara L., as well as seedlings of Pelargonium zonale L. were grown in media containing cotton gin trash compost, rice hulls, peat and perlite in various ratios, and their vegetative growth and flowering was determined and compared with a control medium of 1 peat:1perlite (by volume). When up to 60% of peat in the control medium was replaced by cotton gin trash compost plant height was slightly reduced, except in P. zonale, the number of flowers was increased, except in pot D. grandiflora, and flowering was accelerated in all species except N. oleander. When half or all the perlite of the control was replaced by rice hulls, plant height and flower number was similar to that of the control plants, except in pot D. grandiflora where the number of flowers was reduced and in cut D. grandiflora where both stem length and flower number were reduced; also, in L. camara total replacement of perlite by rice hulls gave short...
TL;DR: An environmental friendly alternative to the use of maleic hydrazide for preventing sprouting in bulb onions is to prolong the natural dormancy by altering the pre-harvest growing conditions.
Abstract: SummaryBecause of increasing concern about the use of chemical growth retardants in crop production, alternative approaches are required. An environmental friendly alternative to the use of maleic hydrazide for preventing sprouting in bulb onions is to prolong the natural dormancy by altering the pre-harvest growing conditions. Onions were grown at various N supplies or subjected to drought stress conditions just prior to harvest. After harvest the bulbs were stored at 1˚C until April, May or June the following year. During a 40.d shelf-life period at 15˚C or25˚C the rate of sprouting was recorded. In plants grown at low N supply, the harvest date was postponed and the yield reduced. A surplus supply of nitrogen did not influence the harvest date or the yield. In contrast, drought stress during the final growth forced the onions to mature earlier. Drought stress reduced the yield and increased the dry-matter percentage of the bulbs. Onion bulbs cold stored until April started to sprout after 20.dat15˚C sh...
TL;DR: It is suggested that fruit susceptibility to CO2-induced core browning is due to oxidative damage and lipid perodixation, and strongly influenced by ascorbate.
Abstract: Summary`Blanquilla' pears (Pyrus communis) were harvested 3.d after the estimated ideal time for commercial harvest and stored for six months in controlled atmosphere (CA) at 2% O2.1.0.7% CO2, 2% O2.+.5% CO2 or in air at –0.58C. The incidence of core browning, concentrations of ascorbate and glutathione and activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), glutathione reductase (GR) and lipoxygenase (LOX) were measured after storage. Core browning only occurred in pears stored at 5% CO2. It was associated with the accumulation of lipid peroxidation products (ethane and thiobarbituric acid reactive substances – TBARS), which is evidence of increasing oxidative damage during CA storage. Lower ascorbate concentrations were observed in CA stored fruits. Despite an important increase in the amount of glutathione at the end of the storage, no significant differences were found for the different atmospheres. Concomitantly, the activity of SOD, APX and LOX increased during stor...
TL;DR: In this paper, the effects of covering fruit with clear plastic film during the final stage of rapid fruit growth were investigated on ‘Big Top’ nectarine and ‘Opal’ peach over three years.
Abstract: SummaryThe effects of covering fruit with clear plastic film during the final stage of rapid fruit growth were investigated on ‘Big Top’ nectarine and ‘Opal’ peach over three years. Covering fruit with plastic film modified the microenvironment around the fruit, particularly by increasing relative humidity and temperature during the day. These modifications influenced fruit development, fruit quality and leaf photosynthesis. Covering fruit with plastic film significantly reduced the dry matter content, either for fruit flesh or for total fruit, the content of total soluble solids in fruit fresh, and leaf photosynthesis under high light intensities (photosynthetically active radiation in excess of 1000.m.mol.m–2.s–1) as compared with uncovered control fruit. The relationship between photosynthetic rate and other leaf physiological responses showed that the depression of photosynthetic CO2 assimilation was related to reduced stomatal aperture and increased leaf temperature. It is suggested that the stomatal...
TL;DR: It appears that the shortened vase life of cold-stored tuberose is not due to the induction of ethylene biosynthesis, and pre-storage pulsing with a 20% sucrosesolution (containing HQC) significantly improved the vaseLife and opening of cold -stored spikes.
Abstract: SummaryThe vase life and floret opening of cut tuberose inflorescences were signifiantly decreased by cold storage The ideal storage temperature was found to be 0˚C for short durations because even storage at 2˚C for only 3d significantly decreased floret opening and the vase life of stored inflorescences There was no signficant difference between “wet”storage in a preservative solution (250ppm 8-hydroxyquinoline citrate, 2% sucrose) and “dry” storage (spikeswrapped in polythene film to reduce water loss) Pre-storage pulsing with a 20% sucrosesolution (containing HQC) significantly improved the vase life and opening of cold-stored spikes The vase life and floret opening of spikes treated in this way were equal, after 6d of storage at 2˚C, to those of fresh cut inflorescences The end of the vase life of cut tuberosespikes coincided with the time taken to return to their initial fresh weight Cold storage resulted in a pronounced increase in ethylene production by the florets, particularly by immatu
TL;DR: It can be concluded that eachexternal quality character is influenced by several growing conditions interacting with each other, and the development of an explanatory model, as a climate control tool to predict and optimize external quality in year-round chrysanthemum production would be of utmost importance.
Abstract: SummaryThe effects of greenhouse climate and plant density on external quality of chrysanthemum (Dendranthema grandiflorum syn. Chrysanthemum morifolium) are reviewed. The external quality aspects analysed in this paper are stem morphology (length, diameter and “strength”), leaf morphology (number and size) and floweringaspects (number, size and position). Increasing assimilate availability level (e.g. higher light intensity, higher CO2 concentration and/or lower plant density) has a positive effect on several external quality aspects of chrysanthemum. It results in longer stems, more lateral branches, a higher number of flowers and increased flower size per plant. Furthermore, both temperature and daily light integral are the main factors that determine stem elongation and time toflowering. Time to flowering is not affected by the CO2level. In general it can be concluded that eachexternal quality character is influenced by several growing conditions interacting with each other. Therefore, the development...
TL;DR: Starch buildup in the Apogee-treated plants appeared to be associated with this effect, suggesting an involvement of a feedback inhibition of photosynthesis in the APOgee-induced stomatal control.
Abstract: SummaryPotted M.26 apple (Mahis domestica) liners were treated with the gibberellin biosynthesis inhibitor prohexadione-Ca (Apogee®) at 0 to 500 mg l”1 as a foliar spray. Apogee inhibited stem elongation, leaf formation, total leaf area and shoot dry weight, while significantly increasing specific leaf weight, root dry weight and root: shoot ratio, regardless of rate. Foliar application of gibberellin A4+7 (GA4+7) at 200 mg l”1 to Apogee-treated plants one day later reversed these effects, especially stem elongation, root dry-matter production and root: shoot ratio. Apogee increased N concentration in stems but not in leaves and roots. There was no effect on the pattern of N allocation amongst organs. GA4+7 increased leaf N concentration but decreased stem and root N concentrations compared with untreated controls, with N allocation shifting from roots to stem. Total nonstructural carbohydrates (TNC), expressed either on a concentration or content basis, increased in all parts of the Apogee-treated plants...
TL;DR: Interactions between irrigation and crop load on fruit size could be due to effects on fruit water relations and photosynthesis, but differences late in the season were significant only for CCL.
Abstract: SummaryInteractions were investigated between irrigation and crop load on photosynthesis, fruit growth and size, and fruit water relations of ‘Braeburn’ apple. The irrigation treatments were a commercially irrigated control (CI) and deficit irrigation (DI) applied throughout the season. The crop load treatments were commercial crop load (CCL) having six fruit per cm2 of trunk cross-sectional area and light crop load (LCL) having four. There were interactions between irrigation and crop load on fruit water potential (Ψfw), fruit turgor potential (Ψfp), and photosynthetic rate (Pn) during mid and late season, and on mean fruit weight at harvest. These parameters were the same for CCL and LCL under CI except for Ψfp which was lower in CCL. Under DI they were lower in CCL than in LCL. For both crop loads DI reduced Ψfw and Ψfp early in the season but from mid-season Ψfp was maintained through osmotic adjustment. Photosynthetic rates were lower in DI than in CI for both crop loads but differences late in the s...
TL;DR: The self- incompatibility in the genus Rosa breaks down with polyploidization, and the relationship between self-incompatibility and ploidy level is discussed.
Abstract: Self- and cross-compatibility was evaluated under field conditions in 48 taxa belonging to all sections of subgenus Rosa and subgenus Platyrhodon in the genus Rosa. Four species exhibited fruit set...
TL;DR: In this paper, the authors used the hydroponic recirculating nutrient film technique (NFT) to grow a cultivar of the Domino pepper at an EC of 2 dS m -1 during the autumn season.
Abstract: Sweet pepper plants of cultivar Domino were grown using the hydroponic recirculating nutrient film technique (NFT) at an EC of 2 dS m -1 during the autumn season. Two experiments examined the effec...
TL;DR: Experiments in glasshouse and controlled environment facilities investigated the effect of different fruit removal and lighting/shading treatments on the pattern of tomato yields, finding that fruit size remained fairly consistent, whereas the number of fruits picked per week exhibited much greater variability.
Abstract: SummaryExperiments in glasshouse and controlled environment facilities investigated the effect of different fruit removal and lighting/shading treatments on the pattern of tomato yields. While the removal of flowering trusses resulted in a yield loss about eight weeks later, there was little loss in cumulative yield as assimilates were distributed to neighbouring trusses. In the growth room experiment, increased photosynthetic photon flux density (PPFD) for one week resulted in a period of increased yield from 4–6 weeks after the start of the treatment, followed by suppressed yields due to smaller fruits on subsequent trusses. However, neither fruit load nor assimilate availability appeared to be responsible for the fluctuations in yield recorded within the glasshouse crop. In this experiment fruit size remained fairly consistent (except when fruit removal treatments were applied), whereas the number of fruits picked per week exhibited much greater variability. This was the case even when all trusses were...
TL;DR: Results of this study suggest fertilizer N is an important N source for fruiting lateral and fruit growth in the on-year and for new Primocane and primocane leaf growth inThe off-year.
Abstract: SummaryMature ‘Kotata’ trailing blackberry plants growing in the alternate-year (AY) system in the field, were treated with ammonium sulfate depleted in 15N in early April, 1997. Based on the whole plant, excluding roots, accumulation of new dry matter over the two year AY production cycle averaged 5.96 kg plant-1. On average, 28, 64 and 8% of this new dry-matter accumulation could be attributed to harvested fruit; loss from the crop as prunings and leaf senescence; and increased dry matter in the crowns for the next growth cycle, respectively. On average, 46% of new dry matter accumulation occurred in the off-year (non-producing). Whole plant (excluding roots) accumulation of new N (labelled and non-labelled) over the two-year AY production cycle averaged 63.7 g N plant” . Over a two-year production cycle, 44% of new N accumulation occurred in the off-year. Of the newly accumulated N, 37% was in harvested fruit, 58% was lost from the crop as prunings, and 5% was accumulated in crowns for the next growth ...
TL;DR: Commercial tree fruit nurseries can promote aggressive tree growth by adding greater amounts of N than is necessary, but this practice often causes physiological problems such as delays in growth cessation, bud dormancy development, and cold acclimation, especially in late apple cultivars.
Abstract: SummaryCommercial tree fruit nurseries can promote aggressive tree growth by adding greater amounts of N than is necessary. Although this practice may produce the largest stock possible, it often causes physiological problems such as delays in growth cessation, bud dormancy development, and cold acclimation, especially in late apple cultivars. In this study, abscisic acid (ABA) was applied to Fuji/M.26 apple (Malus domestica Borkh.) nursery plants that had been growing into the late season with a high N supply. We tested the hypothesis that exogenously applied ABA enhances growth cessation and that this is related to the improvement of bud dormancy development and cold acclimation. We also studied the effects on leaf senescence and mobilization of leaf N into perennial woody tissues. In September 1996, ABA at 1000.mg l-1 plus 0.1% Tween 80 was sprayed twice, at 7.d intervals. ABA treatment significantly enhanced shoot growth cessation and advanced the early stages of bud endodormancy development; these ef...
TL;DR: In this paper, the effects of pressure infiltrated (1.03 X 105 Pa, for 2 min) dilute acetic acid on the shelf-life of a banana (Musa AAB ‘Embul’) were examined.
Abstract: SummaryWhen the effects of pressure infiltrated (1.03 X 105 Pa, for 2 min) dilute acetic acid on the shelf-life of banana (Musa AAB ‘Embul’) were examined, a 0.2% acetic acid (pH 3) treatment showed a significantly low disease score. Of other acids at pH 3 (0.05% citric acid or 0.1% ascorbic acid), tested separately, citric acid significantly reduced disease incidence. A 0.12% benomyl (as ‘Benlate’) dip was the most effective. A three-factor combination of citric acid, acetic acid and `Benlate’, all at half strength showed the lowest disease score. The results indicate that ‘Benlate’ application could be reduced by half when applied concurrently with both citric acid and acetic acid. Firmness was higher in bananas treated with any one of the three acids and the effect was significant using citric acid and acetic acid. Ethylene ripening did not negate this firmness increase. Peel pH was only slightly lower in the acid treated bananas. Anthracnose lesions caused by Colletotrichum musae inoculated into fruit...
TL;DR: The usefulness of molecular markers in revealing the genetic diversity among different sweet cherry genotypes was demonstrated and the high degree of polymorphism of AFLPs provides an efficient system for identification and genome analysis of sweet cherry cultivars and selections.
Abstract: SummaryThe high degree of polymorphism of AFLPs provides an efficient system for identification and genome analysis of sweet cherry (Prunus avium) cultivars and selections. The cultivars of sweet cherry have usually been characterized by assessment of phenotypic and pomological traits. AFLP markers were employed to identify 38 sweet cherry accessions and estimate the genetic diversity among this material. Ten of 18 tested primer combinations were informative with up to 80 bands per primer combination. Seven to 33% of the amplfied bands were polymorphic depending upon primer combination. Allcultivars and selections tested could be clearly identified. The objective of this work was to demonstrate the usefulness of molecular markers in revealing the genetic diversity among different sweet cherry genotypes.