Abstract: The model CropSyst has proven useful for management-oriented simulations of growth and yield of cereals and other field crops, but no scientific information is available with reference to processing tomato. The aim of this paper was to parameterise and validate the crop module of CropSyst for the simulation of potential fruit production in processing transplanted tomato (Lycopersicon esculentum Mill.). Parameterisation and calibration were performed by using field data from an experiment carried out in 1997 in Central Italy. The same set of parameters was validated against five independent experiments, carried out on the same location in 1998, 1999, 2000, 2001 and 2002. The simulation of aerial biomass was always very good, with RRMSE values ranging from 7.5 to 13.4% and modelling efficiencies (EI) always above 0.976. The simulation of LAI was very good during the first part of growing season (up to 40-50 days after transplanting), while the decreasing trend in the final part of growing cycle was not always reliably simulated. Indeed, RRMSE for LAI ranged from 13.5 to 26.8% and EI ranged from 0.849 to 0.966. The differences between simulated and observed final fruit yield were below 10%, except in one year (18% in 2001), confirming the practical value of this model, for management and legislative purposes. For research purposes, it is confirmed that the simulation of dry matter partitioning is a crucial issue in vegetable crops such as tomato, wherein the growth of sources and sinks coexists for a main part of crop cycle.
Manasikan Thammawong and Osamu Arakawa
Faculty of Agriculture and Life Science, Hirosaki University, Bunkyocho, Hirosaki 036-8561, Japan.
Abstract: Fruit maturity indices, i.e. respiration rate and ethylene production, amylose (AM) and amylopectin (AP) content, total hydrolytic activity, and sugar content were investigated during the growth and maturation of 'Tsugaru' (early-maturing) and 'Fuji' (late-maturing) apples (Malus domestica Borkh.). Different starch degradation characteristics during the growth and maturation processes were observed between 'Tsugaru' and 'Fuji'. By iodine staining, the loss of starch in 'Tsugaru' was observed earlier than in 'Fuji'. The different degradation patterns of starch were also demonstrated through the observations on AM and AP content. In 'Tsugaru', AM and AP degraded rapidly between 95 to 110 days after full bloom (DAFB) and almost all starch were lost rapidly at 125 DAFB with simultaneous increases in rate of respiration and production of ethylene. However, in 'Fuji', starch degraded gradually throughout growth and maturation process and was clearly degraded at 170 DAFB with a low level of ethylene production and decreased respiration. In both the cultivars, content of AM and AP were highest in the outer cortex and lowest in the inner cortex. Starch degradation was observed simultaneously in 3 different tissue zones and there was little difference in the total hydrolytic activity among tissue zones in both cultivars. These results suggest that starch hydrolysis in the apple flesh began simultaneously rather than preferentially in any one tissue zone. For sugar content, although differences among tissue zones were not clear, it increased distinctly with loss of starch content. Moreover, sugars from the degradation of accumulated starch and sugar translocation seem to influence mainly the sweetness quality as the fruit ripens.
Reginald S. Fletcher
United States Department of Agriculture, Agricultural Research Service, Kika de la Garza Subtropical Agricultural Research Center, 2413 E. Hwy. 83, Weslaco, Texas 78596
DOI: https://doi.org/10.37855/jah.2009.v11i01.01
Key words: Citriculture, citrus, Citrus spp., Geographic Information System (GIS), soil survey geographic data (SSURGO), Topologically Integrated Geographic Encoding and Referencing (TIGER) data, grapefruit, Citrus paradisi, oranges, Citrus sinensis
Abstract: The South Texas citrus industry needs an inventory of soil properties within existing citrus (Citrus spp.) orchards, wants data at the county level showing soils that are suitable for citrus production, and would value any information related to the establishment of citrus orchards. This study discusses integration of citrus, soil survey geographic data (SSURGO), and U.S. Census spatial and tabular data with geographical information system (GIS) technology for citriculture. For this study, Hidalgo County Texas was evaluated because it is the major citrus producing county in South Texas. The spatial and tabular data and commercial GIS software were used to inventory selected soil chemical and physical properties within citrus groves, to identify orchards that may be affected by urban expansion, and to select potential sites for establishing new citrus orchards. Results indicated that citrus, SSURGO, and U.S. census spatial and tabular data integrated with GIS technology can be a powerful tool for citriculture. The information provided in this study should appeal to producers, extension agents, scientists, and government agencies within the U.S. and abroad.
Berhanu Kebebew and Ketema Tilahun
Oromia Irrigation Development Authority, Addis Ababa, Ethiopia. Haramaya University, Ethiopia.Present address: School of Agricultural and Wine Sciences, Charles Sturt University, Locked Bag 588, Wagga Wagga,NSW 2678, Australia
DOI: https://doi.org/10.37855/jah.2009.v11i01.05
Key words: Crop factor, drip irrigation, Ethiopia, tomato, water use efficiency.
Abstract: Efficient irrigation is essential for sustainable use of available water resources. A field experiment was conducted on two tomato cultivars (Melka Shola and Melkassa Marglobe) and four irrigation deficit levels (0%ETc, 25%ETc, 50%ETc, and 75%ETc). The objective was to determine crop factor (Kf)and water use efficiency (WUE). The Kcfvalues of 0.62, 0.65, 0.70, and 0.71 during the respective four growth stages of the crop were determined. The highest (91.23 kg ha1 mm1) and lowest (81.62 kg ha1 mm1) water use efficiencies were recorded in 25 and 0% deficit levels, respectively. The yield and WUE of Melka Shola cultivar was higher than that of Melkassa Marglobe. Generally, it was found that irrigating the tomato crop with 75% of ETc(i.e. 25%ETcdeficit) is the best irrigation practice in the area. In terms of both yield and WUE, Melka Shola tomato cultivar was found to perform better than Melkassa Marglobe.
Boodia Navindra, Ruggoo Arvind and Boodoo B. Hassina
Faculty of Agriculture, University of Mauritius, Reduit, Mauritius.
Abstract: Green mature jackfruits were minimally processed into cubes, dipped in solution of citric acid (0 and 1%) and ascorbic acid (0, 1 and 2%), vacuum packed at 550 mbar atmospheric pressure in 80 urn laminated low density polyethylene vacuum pouches and stored at 2-4?C for 15 days. A control was prepared, using water. Quality parameters like colour, firmness, pH, titratable acidity and total soluble solids were determined during storage. Colour parameters indicated increase in browning during storage. A significant increase (P<0.05) in titratable acidity and significant decrease (P<0.05) in pH were observed in all treatments. Texture significantly decreased (P<0.05) in all treatments during storage. Combinations of the browning inhibitors were more effective than when applied individually. Citric acid and ascorbic acid when applied together resulted in non-significant change (P>0.05) in microbial counts, browning, and colour lightness. Treatment of 1% citric acid and 2% ascorbic acid in combination with moderate vacuum packaging and low temperature storage was found most effective in inhibiting browning and deterioration of fresh-cut green jackfruit for up to 15 days.
Neji Tarchoun Salah Rezgui and Abdelaziz Mougou
Centre Regional des Recherches en Horticulture et Agriculture Biologique BP47- 4042 Sousse, Tunisia, Institut National Agronomique de Tunisie (INAT) 43, av. Charles Nicolle 1082 cite mahrajene Tunis- Tunisia
DOI: https://doi.org/10.37855/jah.2009.v11i01.07
Key words: Abortion, bud and flower, hot pepper, low night temperature, sucrose synthase, acid invertase.
Abstract: Effects of low night temperature were investigated on two local hot pepper varieties ('Beldi' and 'Baklouti') grown at day/night temperature of either low night temperature regime (25?C/10?C) or optimum night temperature regime (25?C/20?C). The negative effect of low night temperature on floral structure differentiation was registered on both varieties. The deleterious effect was more sensitive on bud stage than on flower buds stage. Abortion of these structures was less important in 'Beldi' than in 'Baklouti'. Floral structure abortion induced by low night temperature was negatively and significantly correlated with soluble acid invertase activity on 'Beldi' (r=-0.82), while on 'Baklouti', both sucrose synthase and insoluble acid invertase activities were correlated with floral abortion (r=-0.78). Under low night temperatures, sucrose synthase and soluble acid invertase activities were reduced to 50%, while the insoluble acid invertase activity was reduced by more than 90%. Enzymatic activities and flowers abortion correlation show a differential response between these two parameters and the developmental stages of flowers.
S. Eyob
Horticulture Department, Awassa College of Agriculture, Hawassa University, P.O.Box 5, Awassa, Ethiopia.
Abstract: Korarima (Aframomum corrorima (Braun) P.C.M. Jansen), a slow growing and persistent under tree shade as an under-story perennial plant, is native to Ethiopia. When it is grown in full sunny condition, all plants die off a few weeks after planting, but the effect of different shading materials on its growth is not known. Half a year old korarima plants were planted under differently coloured plastic shades (red, green, blue and clear) and coffee (Coffea arabica L.) tree shade to regulate the growth. The coffee tree shade was used as control. Varying levels of photosynthetic photon flux density (PPFD) and red to far red (R/FR) ratio of light were recorded under different shaded and open conditions. The korarima plant responded differently to the different plastic and coffee tree shades. Average plant height, number of leaves per plant, number of sprouts per plant, chlorophyll content, leaf area, total fresh and dry weights were significantly different when recorded at different stages of growth, highest being recorded under the blue plastic cover. The minimum efficiency was achieved under control..
Renu Singh, Ram C. Yadav and Neelam R. Yadav
Department of Biotechnology and Molecular Biology, CCS Haryana Agricultural University, Hisar. 125004, India.
Abstract: A study was carried out on mature female papaya (Carica papaya L.) plant of Selection 1 cultivar by using axillary bud as an explant and media supplementation with the main aim to assess the effect of growth regulators (auxins, cytokinins) and silver nitrate on in vitro regeneration of female papaya plant. Total of 28 media were used for shoot regeneration while for root regeneration total of eight media were tested supplemented with different growth hormones. Based on the results of this study, for shoot proliferation, MS basal medium supplemented with BAP (1.0 mg L-1) and BAP (2.0 mg L-1) + NAA (0.1 mg L-1) was found to give the best results while MS medium supplemented with IBA (2.0 mg L-1) gave best rooting percentage. Besides, auxins and cytokinins, effect of silver nitrate (AgNO3) on plant regeneration from axillary buds taken from mature female papaya plant was also carried out.
T Ban, H. Kitazawa, S. Matsumoto, N. Kobayashi, K. Tokumasa, M. Kobatake and T Asao
Faculty of Life and Environmental Science, Shimane University, 2059 Kamihonjyo, Matsue, Shimane, 690-1102, Japan, United Graduate School of Agricultural Science, Tottori University, Koyama-cho Minami Tottori, Tottori, 680
Abstract: The recommendation for a propagation medium of rabbiteye blueberry (Vaccinium ashei Reade) in Japan includes the incorporation of peat moss and Kanumatsuti (a volcanic ash deposit). This experiment compared the use of coal ash (clinker ash) and Kanumatsuti to peat moss as soil conditioner for rooting rabbiteye blueberry cutting. The numbers of cuttings survived and the root dry weight of plants propagated in clinker ash- peat moss mixes were almost the same as cuttings propagated in kanumatsuti- peat moss mix. While the quadratic model between the root dry weight and the clinker ash content in the medium was significant, the maximum root dry weight was estimated to reach about 0.2 g when the proportion of clinker ash in the medium was about 40%. These findings indicate that clinker ash can be used in the propagation medium of rabbiteye blueberry.
Babak Dehghan, Kourosh Vahdati, Darab Hassani and Reza Rezaee
Department of Horticulture, College of Abouraihan, University of Tehran, Tehran, Iran, Agricultural and Natural Resources Research Center, West Azerbaijan, Uromia, Iran, Department of Horticulture, Seed and Plant Improvement Institute (SPII), Karaj, Iran.
Abstract: The study was conducted to determine the effects of different grafting methods and scion cultivars on walnut grafting under controlled conditions in March 2006. Four walnut cultivars ('Z53', 'Hartley', 'Pedro' and 'Serr') were grafted using three bench grafting methods (side stub, omega and whip tongue) onto dormant two years old Persian walnut seedlings as rootstock. The plants after grafting were covered with moist sawdust with relative humidity of 85- 90% and stored in a humid room at 26-28 ?C for 21 days. Based on the results, the highest grafting success was observed with omega (84.33%) followed by side stub (41.89%) and whip tongue (24.31%) grafting, respectively. Significant variations were also observed in graft take and scion growth. The differences among walnut cultivars (scion) on grafting take and scion growth were not significant. However, the scions x grafting methods interaction was significant and 'Hartley' variety grafted by omega method showed the highest graft take (88.44%) among all combinations. A significant positive correlation (R2 = 0.84) was observed between the callus quality and graft takes in all grafting methods.
Zhiwen Li, Baoli Zhou, Yuwen Ding and Xiang Liu
College of Horticulture, Shenyang Agricultural University, Shenyang 110161, China; College of Agriculture and Bioengineering, Tianjin University, Tianjin 300072, China.
Abstract: A simple and effective high-performance liquid chromatographic (HPLC) method for determination of a-solanine in eggplant fruits is described in our study. A new extraction method is established for extracting a-solanine in eggplant fruits. Single and orthogonal tests were designed to analyze the effect of different extraction methods and ultrasonic wave extraction condition on extraction of a-solanine in eggplant fruits. HPLC separation was achieved on a Waters Nova-pak C18 column with the mobile phase acetonitrile-0.05N potassium dihydrogen phosphate (55:45, V/V). The flow rate was 0.7mL min-1 and the UV absorbance was monitored at 202 nm. The optimal extraction method was ultrasonic wave extraction in 70% methanol for 60 minutes at 50oC, and with material to liquid ratio of 1:10. Under the optimal extraction conditions, the average content of a-solanine in skins and flesh of dried eggplant fruits was 0.107?0.006 and 0.626?0.004mg g-1, respectively. The average recovery efficiency was 97.97%.
M. Altaf Wani, G.R. Lawania, R.A. Bhat, Iffiat Fayaz, A. Nanda and Gazenfar Gani
Division of Plant Breeding and Genetics, SK University of Agricultural Sciences and Technology of Kashmir, Srinagar, India. Division of Plant Breeding and Genetics, Allahabad Agricultural Institute-Deemed University, Allahabad, India.Division of Floricult
Abstract: Three different strains of Hypericum perforatum viz. HP-1, HP-2, and HP-3 were subjected to different levels of saline stress (0.25, 0.5, 0.75 and 1.0% with NaCl) and high pH regime (8.5, 9.0, 9.5 and 10.0 with NaOH). Gradual loss in callus growth was observed in all the three strains in response to both kinds of stress. However, high pH showed more drastic effect than saline stress. All the three strains showed higher content of pseudohypercin than hypercin. Change in hypercin production was negligible, however remarkable change was observed in pseudohypercin production in response to both kinds of stress. HP-2 strain produced higher content of hypercin than HP-1 and HP-3 strains under normal as well as under stressfull regime. Proteins were affected qualitatively as well as quantitatively. Maximum numbers of proteins were isolated from control cultures at the retention time of five minutes. Among the three strains maximum numbers of proteins were isolated from HP-3 strain. High pH reduced number of proteins to 12 and 3 while salinity increased number of proteins to 42 and 52 in HP-1 and HP-2, respectively due to accumulation of low molecular weight proteins in response to saline stress.
Carlos R. Bezic, Armando A. Dall Armellina, Omar A. Gajardo, Lucrecia M. Aviles and Silvia L. Canon
Weed Ecology and Control Research Group, CURZA-University of Comahue (8500) Viedma, Rio Negro province, Argentina.
Abstract: Russian knapweed is an invasive creeping perennial herb which affects crops by competition and allelopathy. Herbicides available for use in onion are not able to control Russian knapweed in a crop context. Conversely, recommended products for Russian knapweed are not selective for the crop. The aims of this work were to study Russian knapweed biomass production and propagation for a range of increasing densities in an experimental onion culture and to characterize the productive response of onion plants under these conditions. A partial additive experiment was carried out to study Russian knapweed interference (variable density, 0-64 ramet m-2) on onion transplants (constant density, 40 pl m-2) under greenhouse conditions in Viedma, Argentina (40? 03' S; 62? 48' O). Although no differences among treatments were found for weed final aboveground biomass, low density treatments (0, 2 ramet m-2) were lower than 64 ramet m-2 for belowground biomass. Final weed density was proportional to initial conditions. For onion, total (-54%) and commercial bulb yield (- 56 %) were reduced by weed competition with > 32 ramet m-2. While size 3 bulbs (50-70 mm eq. diam.) were less represented at weed densities higher than 16 ramets m-2, size 4 ones (70-90 mm eq. diam.) were not present in this condition. For A. repens, traits such as the rate of vegetative propagation, high competitive ability, mainly belowground, and high propagule pressure support its high invasive potential.
M. Sciortino and G. Iapichino
Dipartimento di Scienze e Tecnologie Agroambientali, Universita degli Studi di Bologna, Via Fanin 44, 40127, Bologna, Italy. Dipartimento di Agronomia Ambientale e Territoriale, Sezione di Orticoltura e Floricoltura, Universita degli Studi di Palermo, Via
DOI: https://doi.org/10.37855/jah.2009.v11i01.15
Key words: Brassica olearacea L. var. botrytis L., planting density, cultivars, quality
Abstract: New cultivars (F1 hybrids) of cauliflower (Brassica olearacea L. var. botrytis L.) were evaluated at four crop densities (1.3, 1.7, 2.2 or 3.3 plants m-2) for spring harvest crop in a Southern Mediterranean area (western coast of Sicily). The F1 hybrids ('White-Flash', 'Milky-Way' and 'White Excel') having white head, usually cultivated in Northern Italy and Europe in the autumn, were used. The aim was the introduction of new varieties which can fill the gap from mid May to mid July, now existing in the Sicilian cauliflower production, which is based on autochthonous ecotypes of green head varieties, e.g. 'Cavolfiore Verde di Palermo'. Crop density significantly influenced the growth and the phenology of the new hybrids. It was positively correlated to earliness, total marketable yield and inversely to unmarketable product percentage and head size. The best crop density was found to be 2.2 plants m-2. Among the cultivar tested 'White Flash' and 'Milky Way' appeared particularly suited for a spring harvest in the experimental environment. They gave high yields with a minimum discard and uniform heads of approximately 1 kg of weight each.
Funda Eryilmaz Acikgoz
Faculty of Agriculture, Namik Kemal University, Tekirdag, Turkey.
Abstract: The aim of the study was to determine the effect of different sowing times on development and efficiency of some Chinese cabbage varieties (Brassica campestris sbsp. pekinensis)under Corlu conditions. The study was conducted in Corlu County which has a tougher climate than its Province Tekirdag where a similar research had been done before. The research was conducted in 2000 and three different sowing times (15 August, 15 September and 15 October) and four domestic varieties (Tokat-2, Tokat-5, Tokat-29 and Tokat-89) were used. The variety, Tokat-89 and the sowing time of 15 September were found to be the most suitable variety and sowing time, respectively, The variety and time of sowing recorded superiority for head weight, level of hardness and head quality.