Iran's Pistachio Research Institute, Qazvin Station, No.''8, Beheshti Blvd. Agri. & Natural Resources Research Center, Qazvin, Iran.

DOI: https://doi.org/10.37855/jah.2007.v09i02.33

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Abstract: Chilling threshold and growth degree day (GDD) of two main pistachio pistillate cultivars were determined. Layout was factorial based on a complete randomized design with three factors, two cultivars (Qazvini and Ouhedi), 5 thermal levels (+2, 0, -2, -4 and -6 ^oC) and three developmental stages including dormant bud, swelling bud and fully bloomed flowers for chilling studies. Critical temperature for reversible tissue colour change was determined as -4^oC at bud stage, -2^oC at blooming bud and +2^oC at flower. Decreasing temperature down to two more degrees (e.g. -6 ^oC at bud) could shift the damage into the irreversible browning injury. For GDD measurements, three factors, including cultivar, thermal accumulation (calculation based on +4.5^oC) and phenological stages were considered. Kernel filling period varied in two cultivars; Ouhedi's bigger kernel required more time to grow fully and more growth degrees day. Qazvini needed 2561.044 GDD and 138.5 days for total bearing period (flowering to harvest), and 623.363 GDD and 30 days for kernel filling period. Ouhedi needed 2917.823 GDD and 160 days for total period, and 730.61 GDD and 33.5 days for kernel filling.

Plant Biotechnology Centre, Rajasthan Agricultural University, Bikaner-334006

DOI: https://doi.org/10.37855/jah.2007.v09i02.34

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Abstract: Capparis deciduas is an important constituent of desert ecosystem, however, due to population pressure on the land their stands are reducing at an alarming rate. Establishment through root suckers and seeds being very slow and cumbersome, remains the major bottleneck for their reestablishment in the area. Thus, realizing the constraint, a rapid and efficient micropropagation protocol for multiple shoot regeneration employing shoot tip explant was developed. The protocol is more efficient and reproducible than reported earlier. Maximum number of explants (100%) responded on Murashige and Skoog (MS) medium supplemented with 6-benzyl amino purine (BAP) 7 mg L^-1 and naphthaline acetic acid (NAA) 0.1 mg L^-1 while number of shoots per explant were maximum (8.5) on alone BAP 7 mg L^-1. Regenerated shoots could be rooted best on MS medium supplemented with indole butyric acid (IBA) 1 mg L^-1. Rooted shoots could be hardened and transplanted in to the field.

'CECEA - Centre for Agricultural Sciences and Engineering, University of Tras-os-Montes e Alto Douro, Apt. '0'3, 500'-80' Vila Real, Portugal, Department of Plant Science and Agricultural Engineering; CETAV - Centre for Technological, Environmental and Li

DOI: https://doi.org/10.37855/jah.2007.v09i02.35

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Abstract: Chemical composition (crude protein, crude fat, starch, neutral detergent fibre - NDF and free a-amino acids) of six hazelnut cultivars (Butler, Ennis, Fertile de Coutard, Grossal, Merveille de Bollwiller and Segorbe) was investigated. Genotype significantly affected fruit nutritive value. Crude protein ranged from 12-17 g 100 g^-1 dry weight (dw) in cultivar Ennis and Merveille de Bollwiller, respectively; crude fat was 50-62 g 100 g^-1 dw in cvs. Fertile de Coutard and Butler; starch varied from 1.0 to 2.4 g 100 g^-1 dw in cvs. Segorbe and Butler; and NDF was 8-14 g 100 g^-1 dw in cvs. Merveille de Bollwiller and Ennis. Total free a-amino acids content ranged from 144 mg 100 g^-1 dw (cv. Segorbe) to 413 mg 100 g^-1 dw (cv. Butler). The essential amino acids content varied between 23 mg 100 g^-1 dw (cv. Butler) to 55 mg 100 g^-1 dw (cv. Merveille de Bollwiller). Alanine was the main amino acid found (62% of total amino acids) and methionine was the lowest (0.3%). Based on the available data on the phytochemical content of hazelnuts, including the data presented in this study, there is a high likelihood that this fruit will provide positive health benefits.

Departmentof Horticulture, InstitutAgronomique et VeterinaireHassanII, ComplexeHorticole d'Agadir, BP 728, Agadir 80 000, Morocco, Faculte des sciences Mohamed V, 4 Avenue Ibn Battouta B.P. 1014 RP, Rabat, Morocco; Department of Horticulture, Institut Agr

DOI: https://doi.org/10.37855/jah.2007.v09i02.36

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Abstract: For a citrus grower to choose the right clementine cultivar for a given region or market, it is very important to know the characteristics of that cultivar particularly in terms of the development of its internal as well as external quality attributes. In particular, it is very important to know when the maturity index is attained along with the rate of color change, sugar accumulation, acid dissipation, firmness loss, etc. This paper describes the results obtained for several quality attributes (rind color, firmness, juice content, juice titratable acidity and soluble solids content) of seven clementine cultivars sampled at different stages of maturity. All of the cultivars reached minimum maturity index (sugar / acid ratio greater than 7.0) by early November. The rate of rind color change is significantly influenced by picking period and is the main attribute that differs among most of the clementine cultivars. In addition, 'Guerdane', the new clementine cultivar, is the only cultivar that matures much later (January-February) and has the characteristics of a late-maturing cultivar both internally (juice quality) and externally (rind color).

Department of Botany and Microbiology, University of Ibadan, Nigeria. International Institute of tropical Agriculture (IITA), Ibadan, Nigeria.

DOI: https://doi.org/10.37855/jah.2007.v09i02.37

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Abstract: The multiplication ratio for seed yam production is very low compared to other tuberous crops. Seven clones of Dioscorea rotundata Poir (white yam) were evaluated for production of mini tubers from their vine cuttings. Three to four nodes leafy vine cuttings were prepared from the middle portion of the lateral branches collected from mother plants 127, 134 and 141 days after planting (DAP). The lower portion of these nodes were wounded with a clean razor blade and then dusted with 1.0% Indole-3 butyric acid (IBA) powder in order to promote rooting. The mini tubers were harvested 115 DAP. The developed mini tubers varied in sizes among the tested cultivars from 1.9 to 4.2g. The weights were found to be genotype dependent. The survival rate of the planted vine cuttings ranged from 31.1 to 77.1% while the average total number of roots per vine ranged from 5.1 to 5.8. The average number of tubers per vine was 1.8 ?0.8. If these number and weights of mini tubers can be obtained from propagation of vine cuttings, there will be tremendous increase in propagating material thereby making yam cultivation less expensive and also allowing the ware yam only for consumption and other uses.

'Embrapa Cattle Southeast, Rodovia Washington Luiz, Km 234, C.P. 339, 13560-970, Sao Carlos, Sao Paulo State, Brazil; Embrapa Western Amazon, C.P. 3'9, 69011-970, Manaus, Amazonas State, Brazil; Embrapa Soybean, C.P. 23', 8600'-970

DOI: https://doi.org/10.37855/jah.2007.v09i02.20

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Abstract: Banana cultivation is ranked as one of the agricultural activities of greatest economic importance and social significance in Brazil. The area under banana cultivation in Brazil (516,000 ha) is larger than India and Ecuador, leading countires in production, but with rather lower productivity due to lack of adequate crop management, particularly fertilizer application. The objective of this work was to investigate the rate of nutrient retranslocation and the effect of fertilization on the yield and uniformity of banana bunches cultivated in central Amazon region. Two field experiments were conducted in a xanthic Ferralsol (dystrophic Yellow Latosol) - predominant soil of the region, examining: a) the nutrient translocation rate in twelve plants; and b) the efficiency of zinc use, in a completely randomized blocks in split plot design with four rates of ZnSO₄ (0, 30, 60 and 120 g plant¹ cycle¹) and two application times (in the hole together with the seedling or applied in the fifth month after planting), with four replicates. Under the local edaphoclimatic conditions, the results show that N, P, K, Mg and Cu have a high retranslocation rate. The plant yield was influenced by the rates of ZnSO₄, with the most efficient application method being in the planting hole. Results indicated that at high concentrations, zinc had mobility in the phloem from the leaves to the fruits. The proposed critical leaf zinc concentration at the start of inflorescence was 12.9 mg kg^-1 for the third leaf.

Consejeria de Agricultura y Agua de la Region de Murcia. Plaza Juan XXIII. 30008 Murcia, Spain. Instituto Murciano de Investigacion y Desarrollo Agrario y Alimentario. C/Mayor s/n. 30150 La Alberca. Murcia. Spain.

DOI: https://doi.org/10.37855/jah.2007.v09i02.21

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Abstract: Field studies were conducted to compare the yield and fruit quality of processing tomatoes in surface and subsurface drip irrigation, with 100 and 50% of crop evapotranspiration (ETc). The results showed that when irrigation was reduced by 50% ETc the subsurface treatment showed higher water content at root depth compared with the on-surface treatment. At 50% ETc subsurface irrigation yield increased by 66.5% compared with the surface treatment. However at 100% ETc no significant difference in total fruit yield was observed between irrigation methods. The superficial and water-stressed treatment increased the pH and the acidity of the fruits but the subsurface treatment did not show differences with respect to the full-irrigation treatments. Our results show that the subsurface drip irrigation method could be reasonably applied for processing tomato when water resources are limited.

School of Agronomy and Horticulture Science, The University of Queensland, Gatton, Qld.4343, Australia. Present address: Brisbane South Lifestyle Support Services, 48 Duke Street Kangaroo Point, Q 4169

DOI: https://doi.org/10.37855/jah.2007.v09i01.03

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Abstract: The influence of light quality and carbon dioxide concentration on the development of photosynthetic functional structures of strawberry leaves in vitro was examined. We assessed the photochemical quenching parameter of chlorophyll a photochemical efficiency of photo system II (PSII) of strawberry leaves in vitro in a factorial set up. The main effects of light quality; averaged over CO₂ enriched, air flow and closed systems, increased the initial chlorophyll fluorescence value from 485 for yellow light developed PS II system of leaves to 1142 for white light (control) developed ones. The photochemical efficiency of PSII significantly increased from 0.64 under white light to 0.80 for yellow light developed leaves. The leaves developed under blue light were similar to that of control white light for many chlorophyll fluorescence parameters except the initial chlorophyll fluorescence level. The increase in photochemical efficiency of PSII of strawberry leaves can be attributed to lower initial fluorescence values. Under blue light the total dry weight and total chlorophyll content were increased. The possible role of high mercury peak of white light and photoinhibition during development in vitro is discussed.

Department of Chemistry and Biochemistry, University of Massachusetts Dartmouth, 285 Old Westport Road, North Dartmouth, MA 02747 USA.

DOI: https://doi.org/10.37855/jah.2007.v09i01.04

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Abstract: Cranberry callus was successfully induced from cranberry (Vaccinium macrocarpon Ait, Ericaceae) leaves by using Gamborg's B5 medium containing phytohormones at 25^oC in the dark. Anthocyanin-producing cranberry callus was obtained only under conditions of continuous light exposure. Red light and UV light exposure of the callus enhanced anthocyanin content by 41.3 and 29.3%, respectively. The light-dependent anthocyanin production in the callus was regulated by temperature. Anthocyanin content in the callus decreased 81.1% at 42^oC, 58.9% at 37^oC, 47.0% at 30^oC, and increased 10.4% at 4^oC, compared to the callus maintained at 25^oC after 48 hours of incubation at the given temperature. A temperature decrease of 10^oC from 25 to 15^oC resulted in a critical increase of the anthocyanin production in the callus, irrespective of differences in pH of culture medium. The growth of the callus cultured in medium at pH 7.0 was 6.2-fold higher than in the same medium at standard pH of 5.8.

Faculty of Agriculture, Kagawa University, Miki, Kagawa, Japan 761-0795; University Farm, Faculty of Agriculture, Kagawa University, Sanuki, Kagawa, Japan 769-2304

DOI: https://doi.org/10.37855/jah.2007.v09i01.05

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Abstract: Response of low-chill peach cultivar 'Premier' to early forcing culture was studied. Three-year-old trees were forced in a glasshouse from 15 November, 1 and 15 December and 1 and 15 January. Symptoms of insufficient chilling were detected when forcing was started from 15 November and 1 December. Bud break was delayed and sporadic. The flower and leaf buds forced from 15 December and 1 and 15 January rapidly burst within 15 days after the onset of the treatments. The final burst rate exceeded 70%. Generally, flowering started 10-15 days after flower bud burst. The size of the flowers from the trees forced from 15 November and 15 January was smaller than that recorded at other forcing times. Earliest harvest started under forcing from 15 December and 1 January. These results suggested that by using this low-chill cultivar, forcing could be initiated from mid-December, more than one month earlier than for high-chill cultivars, with complete dormancy release, in this region.

United Graduate School of Agricultural Sciences, Tottori University, Koyama-cho Minami, Tottori, Tottori 680-8553, Japan; Faculty of Life and Environmental Science, Shimane University, Kamihonjo, Matsue, Shimane 690-1102, Japan; Department of Soil Science

DOI: https://doi.org/10.37855/jah.2007.v09i01.06

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Abstract: In order to mitigate the autotoxicity in growing plants in closed hydroponic systems, the effects of foliar applications of 2,4-dichlorophenoxyacetic acid (2,4-D) and 1-naphthaleneacetic acid (NAA) on the growth of strawberry were investigated. Although the growth of strawberry plantlets was not affected by the auxin treatments in the fresh nutrient solution, the auxin treatments recovered the growth in the used nutrient solution. Benzoic acid, a compound reportedly accumulating in the reused nutrient solution of strawberry hydroponics, resulted in a significant decrease in the growth of strawberry plantlets at 50 uM concentration, compared to the growth in the nutrient solution without benzoic acid. Mitigation of the growth inhibition caused by the previously used nutrient solution or addition of the high concentration of benzoic acid in the fresh solution was demonstrated by immersing strawberry leaves in the auxin solutions (0.45 and 4.5 uM 2,4-D or 5.4 and 54.0 uM NAA) for two seconds before transplanting. The number of flowers and harvested fruits, and the fruit yield of strawberry plants grown in the greenhouse for about 33 weeks were reduced by the non-renewing the nutrient solutions. These values recovered in the 5.4 uM NAA treatment and were not significantly different from the control (renewal of the nutrient solution). These results suggested that reductions in the number of flowers and the yield of strawberry in closed hydroponic systems appear to be related to the allelochemicals exuded by the plant itself. The auxin such as NAA would avoid the growth reduction of strawberry caused by autotoxicity. The 5.4 uM NAA treatment may be the most effective for alleviating autotoxicity of strawberry and increasing the yield.

Department of Horticulture, Oregon State University, Corvallis, OR, 97331- 7304, USA; USDA-ARS, 45 Wiltshire Road, Kearneysville, WV, 25430-9606, USA, Forestry & Natural Resource Department, Purdue University, West Lafayette, IN, 47907-2072, USA, Departme

DOI: https://doi.org/10.37855/jah.2007.v09i01.01

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Abstract: Production of reactive oxygen species (ROS) is associated with a number of physiological disorders in plants. Superoxide dismutase (SOD) catalyzes the breakdown of superoxide (O₂^-) into O₂ and H₂O₂ and provides the first line of defense against the toxic effects of elevated levels of ROS. The effect of increased expression of Mn superoxide dismutase (Mn-SOD) on salt stress tolerance was studied using transformed tomato (Lycopersicon esculentum cv. Zhongshu No. 5) plants. Northern blots confirmed expression of the heterologous Mn-SOD in transgenic plants. Strong Mn-SOD enzyme activity was detected by native PAGE in transformed plants. Transgenic plants showed resistance to the superoxide-generating herbicide methyl viologen (MV, 10^-4 M). The total SOD activity was one and one half- to two-fold higher, and APX (ascorbate peroxidase) activity was six to seven fold higher in transgenic, than in wild-type (WT) plant under MV stress. Germination of transgenic tomato seeds at a NaCl concentration of 150 mM was greater than wild-type seeds. When exposed to salt stress, roots of transgenic plants were less stunted and leaf injury was lower than that observed in WT plants. Also, the total APX activity of transgenic plants was 4 to 5 fold higher than that of WT under NaCl (200 mM) stress.

Department of Horticulture and Landscape Architecture, Oklahoma State University, Stillwater, OK 74078-6027, USA

DOI: https://doi.org/10.37855/jah.2007.v09i01.07

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Abstract: Tolerance of field- and container-grown lilyturf (Liriope muscari (Decne.)), (Liliaceae) and four species of ornamental grasses (Poaceae), perennial quaking grass (Briza media L.), Japanese bloodgrass (Imperata cylindrica (L.) Beauv. 'Red Baron'), river oats (Chasmanthium latifolium (Michx.) Yates) and dwarf fountain grass (Pennisetum alopecuroides (L.) Spreng. 'Hameln'), to five preemergent herbicides (isoxaben, oryzalin, oxadiazon, oxyfluorfen, and prodiamine) was evaluated. Grasses were planted in the fall of 1997 and in the spring of 1998. Herbicides were applied to the fall planting in the spring of 1998. The April, 1998 plantings received herbicide applications within two or 45 days after planting. Herbicides were applied within two days of planting in May and June of 1998. All species in the field and containers were damaged most by oxyfluorfen, followed by oxadiazon; however, injury was not as severe with oxadiazon as with oxyfluorfen. The oxadiazon-treated plants recovered more quickly than oxyfluorfen-treated plants. Plants were least damaged by prodiamine, oryzalin, and isoxaben. Field-grown Japanese bloodgrass, dwarf fountain grass and lilyturf were generally less damaged when herbicide was applied in June, regardless of planting date or herbicide applied than by the April herbicide application. Prodiamine, oryzalin, or isoxaben caused few phototoxicity symptoms in the species tested, but oxyfluorfen and oxadiazon caused unacceptable injury.

Faculty of Agriculture, Shahid Chamran, University, Ahwaz, Iran.

DOI: https://doi.org/10.37855/jah.2007.v09i01.08

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Abstract: In Khuzestan (South Iran), onion bulbs are usually formed and harvested in spring and consumed either in the same season or during summer while some of these are kept for seed production. In order to study the losses in onion bulbs under hot store conditions, an experiment was conducted in autumn 2002 and spring 2003. The data were collected on five cultivars being produced at Shahid Chamran University, two local cultivars and three of those under commercial cultivation. The collected bulbs were kept in 30 x 50cm boxes, 15 cm in height. The experiment was replicated three times in completely randomized design. Data on change in number, weight of the healthy bulbs and decayed bulbs were recorded every 15 days. No bulb root was produced during the storage when maximum, average and minimum temperature were 48, 33 and 25^oC, respectively with the average relative humidity (RH) of 30%. As far as storage life was concerned, there was a significant difference among the varieties. Compared to both the local and market bulbs, those produced at Shahid Chamran University showed more storage life. Another important finding of this research was that 50% of the local and university bulbs remained unspoiled after 120 days, whereas the Taxes Yellow Grano, Taxes Early Grano and G1 had the short storage life; 50% of the stock were destroyed after 60 days. In the present study, Aspergillus niger was found to be the most important factor responsible for onion decay in hot stores of Khuzestan.

Centro Universitario de Investigacion y Desarrollo Agropecuario Universidad de Colima. Km 40Autopista Colima-Manza-nilloTecomdn, Col. 28100Mexico. InstitutoNacionaldeInvestigacionesForestales, Agricolas y Pecuarias. Campo Experimental Tecomdn.

DOI: https://doi.org/10.37855/jah.2007.v09i01.09

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Abstract: In cantaloupe farming (Cucumis melo L.), the production of export quality fruit require nutritional indicators that allow an adequate management of nitrogen fertilization and irrigation water supply. This study with cantaloupe muskmelon was carried out to test four nitrogen fertilization treatments and three levels of soil moisture tension under field conditions. Nitrate content (N-NO₃) in the cellular extract was evaluated as an indicator of nutritional status. Significant correlation was found between the lowest nitrate concentrations in the petiole sap and the N fertilization doses in three different sample periods. The effect of soil moisture tension on nitrate concentration varied in both years; this was attributed to soil temperature differences. Results showed that it is feasible to establish outcome predictions of yield and quality of the fruit based on the nitrate concentration in petiole sap, concluding that this is an adequate indicator of the nutritional status of the cantaloupe plant. However, its use as a guide for managing fertilization and irrigation must include a permanent follow up of the crop that evaluates the effects of environmental factors in plant growth and uptake of the nutrients.