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Volume 2 Numbers 1 & 2 2008 
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CONTENTS AND ABSTRACTS
Number 1
Antonio Dell’Aquila (Italy) Perspectives in Probing Seed Germination and Vigour (pp 1-14)
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ABSTRACT
Invited Mini-Review: This paper reviews the developments of techniques which are applied in seed quality, in terms of germination and vigour testing. First the definition of seed germination, viability, and vigour derived from evaluation methods over the last four decades will be reassessed to account how new techniques need to satisfy the demand of farmers, seed industries, seed-gene banks and basic seed research. The course of development of seed quality testing techniques is associated with that of basic knowledge and insight into seed morphology, physiology, biochemistry and molecular biology. Related vigour indices, mostly assessed in a destructive manner, are generally used to establish correlations with declining seed viability. The classical tests are widely reviewed and problems inherent to their application are discussed. A new generation of seed quality testing techniques, such as computer imaging analysis, NMR-microimaging and X-ray inspection, chlorophyll fluorescence sorting, infrared-photoacoustic and electrical impedance spectrometry, and micro-calorimetry, contributes to improve relationships between different seed characteristics and viability in economically important crop species. In the future perspectives section, I focus on the interest of seed researchers and analysts in introducing new automated and computer-aided testing systems in a seed laboratory. The ultimate goal should cover two aspects: First, the definition of non-destructive markers in testing and sorting seed quality, suitable also to be applied on an individual seed within a seed population in automated way, and secondly, the integration of new testing technology with standard methods in a seed laboratory where a large number of seed species may be evaluated for genetic purity analysis, taxonomic variability screening, and viability and vigour prediction.
Alicia Gamboa-deBuen, Alma Orozco-Segovia (Mexico) Hydrophyllaceae Seeds and Germination (pp 15-26)
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ABSTRACT
Invited Review: Germination of members of the Hydrophyllaceae family has been extensively studied, to shed light on basic germination mechanisms and to determine the evolved reproductive strategies that enable species to adapt to different environmental conditions. The effect of environmental factors on seed development and on seed soil permanence has been studied in Hydrophyllum appendiculatum, Phacelia secunda and Wigandia urens. Metabolic changes of osmotically conditioned W. urens were also investigated. The effect of fire on seed germination has been studied mainly in Emmenanthe penduliflora and several Phacelia species. These studies include the effect of smoke products on germination of different Hydrophyllaceae species. The mechanisms involved, and the effect of the putative main promoter of smoke have also been determined in several Hydrophyllaceae. The basic mechanisms of dormancy in relation to light and temperature inhibition have been determined in seeds of Nemophila insignis and Phacelia tanacetifolia.
Danuta Packa, Hanna Jackowiak, Tomasz Góral, Marian Wiwart, Juliusz Perkowski (Poland) Scanning Electron Microscopy of Fusarium-Infected Kernels of Winter Triticale (x Triticosecale Wittmack) (pp 27-31)
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ABSTRACT
Original Research Paper: Infection tests involved kernels of four winter triticale (x Triticosecale Wittmack) cultivars, which showed different infection severity following artificial inoculation of triticale heads with an aqueous suspension of Fusarium culmorum (W.G.Smith) Sacc. spores applied at mid-anthesis. After threshing, the concentration of ergosterol, an indicator of fungal biomass, was determined in kernels. Kernels, which differed in their severity of infection, were examined using scanning electron microscopy (SEM). We confirmed the presence of hyphae both on the surface and in the tissues of triticale kernels. Observations of the endosperm of severely infected kernels, classified as FDKs (Fusarium damaged kernels), proved the presence of hyphae in the endosperm and changes in its structure such as damage of its cellular structure, loose arrangement of starch granules, disappearance of small starch granules and damage to large starch granules. The microscopic image of the starch endosperm of triticale FDKs resembles that of wheat FDKs.
Elias Soltani, Serolla Galeshi, Behnam Kamkar, Farshid Akramghaderi (Iran) Modeling Seed Aging Effects on the Response of Germination to Temperature in Wheat (pp 32-36)
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ABSTRACT
Original Research Paper: Seed germination is strongly dependent on temperature. Reduced germination rate as a consequence of seed aging might be due to changing the type of response function to temperature or changing the parameters that govern the function. The objectives of this research were: (1) to determine the effect of seed aging on the type of response function describing the relationship of germination rate to temperature, and (2) to evaluate how the parameter(s) of the response function are changed when the germination rate is reduced as a result of seed aging. Seeds (cv. ‘Zagros’) were kept at a high temperature (43°C) and high relative humidity (90-95%) to create different classes of seed aging. Seed aging had no effect on the type of response function or cardinal temperatures. A dent-like function adequately described the response of germination rate to temperature in all the aging treatments. Cardinal temperatures of 2.2°C for the base, 28.6°C for the lower optimum, 38.0°C for upper optimum and 45°C for ceiling temperatures were obtained. Inherent maximum rate of germination (Rmax) was the sole parameter that was affected by seed aging periods and characterized differences between seed aging periods with respect to germination rate at various temperatures.
Marcin Kozak, Dariusz Gozdowski, Zdzisław Wyszyński (Poland) Does Number of Kernels per Spike Follow a Normal Distribution in Spring Barley? (pp 37-41)
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ABSTRACT
Original Research Paper: In this paper we investigate whether distribution of number of kernels per spike, which is a component of small grain cereal yield per spike, can be approximated by a normal distribution in spring barley. We emphasize that this trait is not the same as mean number of kernels per spike, which is normally considered in the classical yield component analysis (conducted for grain yield per unit area or per plant), even though the latter is referred to by the same name as the former; we consider this a mistake in terminology. Hence we suggest that in classical yield component analysis one should use the correct name of mean number of kernels per spike. Further, our study shows that the distribution of number of kernels per spike in spring barley is usually not normal, although in some situations it follows the pattern of this distribution. The Box-Cox transformation seldom led to approximate normal distribution of this trait.
Number 2
Cileide Maria Medeiros Coelho (Brazil), Vagner Augusto Benedito (USA) Seed Development and Reserve Compound Accumulation in Common Bean (Phaseolus vulgaris L.) (pp 42-52)
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ABSTRACT
Invited Review: Much of what we know today on the molecular aspects of seed development comes from basic studies carried out in the model species Arabidopsis. However, many differences exist between the developmental programs of the small seeds of Arabidopsis, basically without nutritional reserves, and the crop legume seeds, which are bigger and accumulate nutrients designated to germination. Since seed nutritional reserves are essential to guarantee food production, it is important to understand the genetic, biochemical and physiological mechanisms favouring a better incorporation rate of the main reserve compounds in seeds, such as proteins, carbohydrates, lipids and minerals, which will foster breeding programs towards more productive and efficient genotypes. Here, we review the current understanding of seed development of common beans as well as refer to conserved developmental mechanisms between this and other related species. The state of the art of biochemistry, genetics and physiology, including protein, hormonal and nutritional interactions, during seed development of common beans and the perspectives to further understand and control it are discussed with emphases on metabolic pathways, and nutrient transport and storage compounds. The text also alludes to crop management favouring incorporation of certain substances or altering the proportion of storage compounds and genotypes that store more efficient forms of phosphate than phytates. Additionally, we discuss the major challenges and perspectives for future investigation on controlling mechanisms of the main reserve compounds in common bean seeds.
Behnam Kamkar, Mansoureh Ahmadi, Afshin Soltani, Ebrahim Zeinali (Iran) Evaluating Non-Linear Regression Models to Describe Response of Wheat Emergence Rate to Temperature (pp 53-57)
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ABSTRACT
Original Research Paper: We aimed to formulate and validate mathematical functions that can be used to determine cardinal temperatures and the effect of temperature on biological days required from seeding to emergence of wheat cv. ‘Tajan’. For this purpose, different non-linear regression models including flat, logistic, quadratic, cubic, dent-like, segmented and Curvilinear were used. Root mean square of errors, coefficient of determination and regression coefficients of predicted versus observed values were used to find the appropriate model. Investigating regression coefficients indicated that only in flat and logistic models, related coefficients were not significant. Other models (quadratic, cubic, dent-like, segmented and curvilinear) were not used to select the best model. Because the root mean square of errors was less in the logistic model than in the flat one, the former was chosen as the best model to describe the response of emergence rate to temperature. Using this function, base and optimum temperatures were 5.2 and 24.8°C. This function and its parameters can be used in wheat simulation models to predict seedling to emergence duration based on a thermal time concept. Also, required biological days from seeding to emergence using these models varied from 2.78 to 3.98.
Mehmet Serhat Odabas, Cuneyt Cirak, Ali Kemal Ayan, Omer Caliskan (Turkey) Modeling the Effect of Different Pre-soaking Treatments on Seed Germination in Stinging Nettle (Urtica diocia L.) (pp 58-60)
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ABSTRACT
Short Communication: The aim of this study was to determine the effect of different pre-soaking applications on stinging nettle (Urtica diocia L.) germination in vitro with mathematical modeling. Pre-soaking applications were control, hot water (HW), gibberellic acid (GA) and sulfuric acid (H2SO4). Seed from stinging nettles were investigated by mathematical models based on temperature. For this reason a model D = a-(b ×T)+(c × T2) produced for predicting the time to emergence in relation to temperature for stinging nettle was utilized. Optimum temperature for seed germination was calculated by using the coefficients T0 = [-b / (2 × c)] obtained from the regression models of the days to germination GR = (12.983) - (0.458 × T) + (0.009 × T2), which was found to be 26°C. The regression coefficient was R² = 0.99 for germination percentage. Depending on the days to germination the effect of H2SO4 changes on germination was SA = (-19.309)+(5.701 × D)-(31.576 ×SAR) where D is number of days and SAR is H2SO4 rate. Depending on the days to germination the effect of GA changes on germination is GA = (29.567)+(0.165 × D)-(0.001 × GAR2) where D is day and GAR is GA3 rate. The effect of HW application is HW = (50.699)-(2.858 × D)+(0.624 × T) where D is number of days and T is temperature. Regression coefficients were R² = 0.95 for H2SO4 application, R² = 0.89 for GA application and R² = 0.69 for HW application.
Rakesh K. Dubey, Hari Har Ram (India) Genetics of Seed Yield and its Components in Bottle Gourd (Lagenaria siceraria (Mol.) Standl.) (pp 61-64)
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ABSTRACT
Original Research Paper: Genetic studies on seven traits of bottle gourd viz. days to first male flower, node to first female flower, number of primary branches per vine, fruit weight, pedicel diameter, number of seeds per fruit and 100-seed weight, were studied. Dominance components (H1 and H2) were significant for node number to first female flower and number of primary branches per vine. The degree of dominance averaged over two seasons (kharif and summer) (H1/D)1/2 was observed to be greater than unity for node number to first female flower, number of primary branches per vine, fruit weight, pedicel diameter, number of seeds per fruit and 100-seed weight, suggesting the presence of overdominance. The ratio of dominant and recessive alleles (4DH1)1/2 + F/(4DH1)1/2 – F was greater than unity for days to first male flower, node number to first female flower, fruit weight, pedicel diameter, number of seeds per fruit and 100-seed weight. The proportion of positive and negative effects of genes (H2/4H1) in the parents was not less than its maximum theoretical value (0.25) for the characters, i.e., number of primary branches per vine, fruit weight and pedicel diameter. However (H1/4H1) was almost equal to its maximum theoretical value in this investigation. In the F1, additive gene action was predominant, thus suggesting seed yield improvement through selection in bottle gourd.
Ravindra B. Malabadi (Canada/India), Jaime A. Teixeira da Silva (Japan), Gangadhar S. Mulgund (India) Smoke-Saturated Water Influences in Vitro Seed Germination of Vanda parviflora Lindl. (pp 65-69)
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ABSTRACT
Original Research Paper: This study for the first time reports the influence of smoke saturated water (SSW) on asymbiotic seed germination and an early differentiation of protocorms and plant regeneration of Vanda parviflora Lindl. High percentage germination (95%) and high percentage of plantlet recovery (93%) was achieved by culturing seeds on Mitra et al. (1976) basal medium supplemented with 10% (v/v) SSW. Rapid regeneration was observed within 60-70 days of culture on this medium where the majority (93%) of propagules developed leaves and roots. Well-rooted shoots were transferred to pots containing charcoal chips, coconut husk and broken tiles (2:2:1) and 90% survived. This study emphasizes the role of SSW as a natural additive at different stages of development from seed germination to plant regeneration. These results also suggest that the germination stimulatory activity of SSW at 10% (v/v) could be applied for micropropagation of other orchids as a low cost method. The added benefit of this protocol is that it can be transferred to a rural community surrounded by rich orchid diversity in the Western Ghat Forests of Karnataka state with less technical know-how where small-scale tissue culture units can be set up to generate employment as well as to conserve biodiversity.
Shweta Singh, M. M. Jana, Sulekha Hazra (India) Ex Vitro Performance of Peanut Plants from TDZ-pretreated Seeds (pp 70-73)
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ABSTRACT
Original Research Paper: Thidiazuron (TDZ) is a potent regulator of morphogenetic responses in a large number of species. The activity of TDZ varies widely depending on its concentration, exposure time, explant and species. In the present experiment, the effect of TDZ on peanut seed germination and seedling growth was evaluated by soaking the mature seeds of cultivar SB-11 for 12 h at various concentrations of TDZ before sowing in a sand: soil mixture in pots and growing the plants for 17 weeks (crop duration of this cultivar is 110-115 days) in a greenhouse. Shoot and root elongation was reduced in the seedlings raised from TDZ-treated seeds. Elongation of the hypocotyl remained unaffected. Flowering was delayed in seedlings raised from TDZ pretreated seeds. Flowering was further delayed in the plants raised from seeds treated with higher concentrations of TDZ. Flowers and flower buds were noted at the cotyledonary node during harvesting of plants raised from seeds treated with 22.71 µM TDZ. The number of pods was optimum in plants developed from seeds treated with the lowest concentration (2.27 µM). There were no nodules on hypocotyls of TDZ-treated seed-derived seedlings. In the control, the hypocotyl was full of nodules. The effect of TDZ pretreatment has never been tested on peanut seed germination and seedling growth. Retarded growth and delayed flowering indicated that the amount of TDZ absorbed by the seeds affected the plant through its entire life cycle.
Rotimi Ayodele Oderinde, Adewale Adewuyi, Ibironke A. Ajayi (Nigeria) Determination of the Mineral Nutrients, Characterization and Analysis of the Fat-Soluble Vitamins of Caesalpinia pulcherrima and Albizia lebbeck Seeds and Seed Oils (pp 74-78)
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ABSTRACT
Original Research Paper: The seeds and seed oils of Caesalpinia pulcherrima (CP) and Albizia lebbeck (AL) were analyzed for their proximate composition, physico-chemical characteristics and levels (ppm) of selected toxic trace metals (Fe, Mn, Cu, Pb, Cd and Zn) and macro nutrients (Na, K, Mg and Ca). The fatsoluble vitamins were also investigated using HPLC. These seeds are good sources of protein, carbohydrate, fat-soluble vitamins and minerals. Triglyceride was the dominant lipid species in the oils while sterol was the major component of the unsaponifiable matter. Potassium was the most abundant metal in the seeds and oil. The physico-chemical characterization of the oils suggests a good industrial application of these oils.
Rotimi Ayodele Oderinde, Ibironke A. Ajayi, Adewale Adewuyi (Nigeria) Evaluation of the Mineral Nutrients, Characterization and some Possible Uses of Blighia unijugata Bak. Seed and Oil (pp 79-82)
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ABSTRACT
Original Research Paper: The kernel (KL), aril (AL) and mixture of the kernel and aril (KAL, in a 1:1 ratio) of Blighia Unijugata Bak. were analyzed for their proximate composition, physico-chemical characteristics and levels (ppm) of selected toxic trace metals (Fe, Mn, Cu, Pb, Cd and Zn) and macro nutrients (Na, K, Mg and Ca). The oil yield was 50.82% for AL, 14.15% for KL and 29.00% for KAL. The saponification and iodine value suggest their possible use in liquid soap, shampoo and oil-based ice cream production. The crude protein was 19.90% for AL, 14.00% for KL and 16.70% for KAL. The moisture content of AL (3.30%) was the lowest compared to those of KL (6.10%) and KAL (4.70%), suggesting that AL might exhibit the most stable shelf-life characteristics. Triacylglycerol was found to be the dominant lipid species in the oil with KL (90.80%) being higher than AL (88.30%). Sterol was also the major component of the unsaponifiable matter. The concentrations of the macronutrients were high with K (1559 ± 0.78 ppm) being the highest in KAL. The concentration of the trace metals also differs, with Zn (46.77 ± 0.01 ppm) being the highest in KL. The oils extracted from them were also found to be rich in macronutrients and had considerable amount of trace metals. Thus, the seeds could be considered as good source of minerals with the possibility of use as feed supplements and their oils for edible purpose and industrial applications.
J Rajesha, MA Harish Nayaka, Basavaraj Madhusudhan, MD Shylaja, M Karuna Kumar, GA Ravi Shankar (India) Antioxidant Potential of Secoisolariciresinol Diglucoside Isolated from Different Fractions of Flaxseeds (pp 83-88)
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Original Research Paper: Flaxseed lignan (secoisolariciresinol diglucoside; SDG) was isolated from dehulled flaxseed fractions such as hull, endosperm and flour of LVF-01 and GVF-03 varieties and were analyzed using HPLC. The flaxseed fractions containing SDG were evaluated for 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and reducing power. An EC50 of 12.6, 16.4 and 0.016 mg/mL were observed for hull fractions of LVF-01, GVF-03 and standard SDG, respectively. The flour fractions of both varieties showed moderate activity compared to hull fractions with an EC50 between 24 and 27 mg/mL, respectively. Least activity was observed in the endosperm fraction of LVF-01 (EC50 = 320 mg/mL) and GVF-03 (EC50 = 330 mg/mL) varieties. Further, dose dependent reducing power was observed in all the fractions. The hull fraction of LVF-01 showed 1.79- and 7.87-fold higher activity compared to their flour and endosperm fractions, respectively. Similarly, the hull fraction of GVF-03 showed a 1.41- and 7.31-fold higher activity than flour and endosperm fractions, respectively. In addition, at 3.0 mg dosage both LVF-01 and GVF-03 hull fractions offered protection to DNA against hydroxyl radical induced damage suggesting the antioxidant potential of SDG in flax seed fractions. |
