A screen house study was carried out to assess the effects of three organic amendments (poultry droppings – pd, brewer's spent grain – bsg and wood shavings-ws) on the germination of four crops (Maize: Zea mays, Cowpea: Vigna sinensis, Okro: Abelmoschus esculentum and pepper: Capsicum annum), and on some properties; of an ultisol in Port – Harcourt, southeastern Nigeria. The four treatments, made up of the organic amendments were laid out in a completely randomized design replicated thrice, for each of the crops. Wood shavings were best suited for pepper and maize with 77.7 and 43.3 percents germination, respectively as against their controls of 59.9 and 33.3 percents. Brewer's spent grain gave a germination rate of 60% for cowpea while the poultry droppings treatment gave 100% germination for okra. Generally, the wood shavings enhanced germination for all the crops. Organic amendments reduced bulk density by 8.2,4.5 and 38.1% and increased porosity by 10.2, 6.1 and 40% for poultry droppings brewer's spent grain and wood shavings respectively. Wood shavings and poultry droppings significantly increased volumetric moisture contents from 0.37 to 0.50 and 0.43 respectively. There were inverse linear relationships between percentage germination and volumetric moisture contents for all treatments, with r-values of -0.06, -0.54, and -046 for PD, BSG and WS respectively. There were also the same relationship between percentage germination and bulk density for only PD and WS respectively. There were also the same relationship between percentage germination and bulk density for only PD and WS with r-values of -0.31 and -0.83 respectively. International Journal of Agriculture and Rural Development Vol. 7(2) 2006: 134-140

Experiments were carried out to investigate the germination traits of Fraxinus lanuginosa fruits. The optimal temperature for germination was 20 deg C; although fruits at lower temperatures (10 deg C and 15 deg C) retained their viability, and their germination was inhibited. While seeds extracted from fruits showed significantly higher germination percentages than intact fruits, partial scarification of the pericarp to enhance water permeability to the inner seed did not facilitate germination. This indicates that the dormancy of the fruit is mainly due to the physical inhibition of embryo growth by the pericarp. A pre-moist chilling treatment had a significant effect on breaking dormancy and enhancing the germination rate. However, since a substantial number of intact fruits was able to germinate without pre-treatment, we concluded that the dormancy of F. lanuginosa fruit is not very deep. These traits would be sufficient to prevent precocious germination of F. lanuginosa during the fruit-dispersal season in southeastern Hokkaido, Japan, which was characterized by a cool autumn followed by a severe winter.

Guayule (Parthenium argentatum Gray), a latex producing shrub from northern Mexico and southwestern Texas, has been considered a viable alternative commercial crop for arid lands throughout the world. Stand establishment by direct seeding has been ineffectual because of problems with seed germination. Seed dormancy has been ascribed as one of the main reasons for low germination. Special seed treatments, such as physical and chemical conditioning, have been devised to overcome embryo and seed coat dormancy, thereby improving germination and emergence. However, the treatments described in the literature have not been as effective as expected, and many of them are costly and time consuming. The objective of this study was to determine the effects of nine preconditioning treatments on the percentage and rate of germination and emergence, and seedling fresh weight. Three-year-old seed of lines AZ-101, AZ-3, and N9-3 were analyzed with X-ray to determine the seed lot quality. The results showed differences in quality (defined as seeds containing embryos and endosperm) among the three lines; however, no differences were found for percentage and rate of germination and emergence, and seedling fresh weight among the nine treatments. These results suggest that in older seed lots seed quality is of greater importance in determining germination and emergence than conditioning treatments.

The main objectives of this project was evaluation of seed samples of medicinal plant with different provenances of different stats of Iran for different seed technology test including: physical purity, genuineness of seed (genetically purity), thousand weight , determination of seed moisture content, seed healthy test, seed germination and seed vigour test in standard germination test. These type of seed test were carried out for the all seed samples of medicinal plant with different provenance in laboratory of seed gene bank. Also some specially test like pre- cold test, determination model of seed storage behavior, effect of dry storage (room temperature) and cold room temperature on germination and vigour, accelerated ageing test were carried out for some special of medicinal plant seeds by experimental design. Regarding to seed healthy test, seed samples of some species collected from different regions of Iran, were chosen for seed health testing. After cleaning and determination of physical purity, the seed samples were analyzed for determination of seed borne mycelia (fungi) and insects. Damaging effects of seed borne pest were observed on the seed samples, but there were not any life cycles of insect (adult, larva and pupa). The infected seeds were separated from healthy seed. Also for determination of mycoflora (seed borne fungi), with the trace of damaging, shapes of symptoms on the seed and their color were used for identification of healthy seeds from non-healthy seeds. The infected seeds were cultured on Potato Dextroz Agar (PDA), after growing of fungi, four genera called Penicillium, Alternaria, Aspergilus, Rhizopus and Fusarium were isolated from the seed samples. Moreover, the seed quality (percentage of germination and speed of germination) of infected seeds to seed borne fungi were compared to healthy seeds . In other experiment, for model determination of seed storage behavior, the seed samples of some medicinal plants from different state of country were processed and analyzed. The processing of the seed samples included for physical and genetically purity, seed healthy test, thousand weight, moisture content determination, germination test, packaging and conservation of the seed samples in cold room of gene bank. Evaluation and determination of model of seed storage behavior was the main point of this research work. By determination of moisture content, the model of seed storage behavior of medicinal plant seeds was identified and most of them have orthodox seed storage behavior. Therefore their conservation should be done as ex situ conservation. By pre-chilling treatment comparing of normal condition, total speed of germination and vigor index of seeds of 9 medicinal plant species were studied by an experiment. The vigor indexes were calculated by following equation: percentage of germination * mean of total length of root and shoot. The results were a function of the results of percent of germination and total speed of germination. With an experiment, the seeds of two medicinal species (Eruca sativa Lam. and Anthemis altissima L.) under two cold room (4°C) and dry storage (room temperature) conditions were maintained over six months and tested by standard germination test. The physiological quality of the seed rocket plant had not any significance differences in two conditions. The reason might be due to non-physiological dormancy of the seed species. Whereas, percent of germination in the species of chamomile was significant in the two conditions. As it is clear the percent of germination of the chamomile from dry storage condition was higher from cold room condition and this due to physiological dormancy of plant seed which overcome by dry storage condition. The speed and vigor index of plant seed had no significant differences in two conditions. For evaluation of seed quality traits (germination percent, rate of germination and vigor index) in Moldavian balm (Dracocephalum moldavica L.) an experiment was conducted using accelerated aging test (AAT) under laboratory condition. The seed samples were subjected to 40 0C in 100% relative humidity for 0, 12, 24, 48 and 72 hours. A completely randomized design with 3 replications was used. The results showed significant differences among treatments for germination percent, rate of germination and vigor index. There were no significant differences between 0, 12 and 24 hours AAT treatments for germination percent and rate of germination, but AAT treatments for 48 and 72 hours significantly decreased germination percent and rate of germination compare to 0, 12 and 24 hours. Increasing the time of AAT treatments decreased all of the three seed quality characters. The vigor index was affected more than the two other quality characters. The effect of AAT duration treatments on vigor index reduction was as fallow: 0 18, 24 48, 72. It is concluded that under conditions of this experiment, the vigor index is more sensitive trait for seed quality evaluation of Moldavian balm (Deracocephalum moldavica L.) seeds. For determination and evaluation of percent of germination, total speed of germination and vigor index of the seed of 17 species of medicinal plants, according to the International Seed Testing Association, different tests including standard germination test and accelerated ageing test were used. Among those species, some species were resist and some species were not, nevertheless the percent and speed of germination, of those seed samples which is resist to accelerated ageing, are meaningful, comparing with non-aged seeds.

There is extensive variability in physical and chemical properties among brands of retail potting media. The purpose of this study was to assess variability in seed germination and plant growth responses among and within brands. Twenty-four different brands of media, and multiple bags of five brands, were purchased at nine retail stores. Tomato (Lycopersicon esculentum) seeds were germinated in 11 different brands of media and in media from different bags of four of the same brands. Marigold (Tagetes erecta) and petunia (Petunia xhybrida) were grown to flowering in 10 brands of media. Germination varied significantly among media brands and among bags of one of the brands. Plant performance also varied significantly, with several of the brands producing plants with few flowers, long times to flowering, and low shoot and root dry weights even though all treatments received uniform applications of a complete fertilizer solution three times per week. Few relationships could be discerned between individual physical and chemical properties of the media and plant performance. Results indicate improvements in quality among brands and quality control within brands are needed in the retail potting media industry. Quality assessment tools emphasizing plant performance could improve overall media quality.

We describe effects of salinity and temperature on germination characteristics of three dominant macrophytes, Phragmites australis, Juncus acutus, and J. kraussii, located in wetlands along the Hunter River, New South Wales, Australia. These wetlands were altered, from estuarine to freshwater habitats, by flood mitigation activities initiated during the 1970s. Tidal restoration to approximately 300 hectares of the marsh is planned to occur by 2008, with the goal to reduce freshwater vegetation in favor of salt marsh species. We determined if timing restoration projects to coincide with natural germination cycles or seasonal conditions of high salinity would be disadvantageous to P. australis or J. acutus germination. Germination trials lasted 25 days under two temperature range treatments (10–25 and 15– 30°C) and a salinity gradient (0–30 ppt). Many P. australis seeds commenced decomposition after three days (up to 58%). Increased salinity lowered germination in all species; however, only P. australis was influenced by temperature. Phragmites australis germinated in all conditions, although germination rate was low (2% ± 1.7) in the highest salinity treatment at high temperature regime. Both Juncus species obtained 100% germination in freshwater, failed to germinate in the highest salinity, and seed viability was not affected by 25 days emersion in high salinity. For areas dominated by P. australis in eastern Australia, we suggest that tidal reinstatement should be initiated in late autumn when P. australis seed banks are low. Additionally, periods of heavy rainfall, which reduce soil salinity, may help other species colonize the area. Further studies are required to determine characteristics of J. acutus that can be used to repress the species spread along the eastern coast of Australia. Currently, active measures involving chemical and physical weed suppression, litter removal, and mass planting of native species, are likely to be required to achieve management goals.

El mistol (Ziziphus mistol Grisebach) es una especie arbórea nativa de Argentina, con múltiples usos como alimenticia, tintórea, maderera, medicinal y melífera. El fruto del mistol es una drupa con endocarpo leñoso que dificulta la germinación de las semillas. El objetivo de este trabajo fue seleccionar tratamientos pregerminativos para superar la dormición física impuesta por el endocarpo. Los endocarpos se trataron con escarificación física (remoción completa y desgaste del tejido de la zona basal externa), ácida y húmeda. Las pruebas de germinación se realizaron sobre papel (semillas) y en arena ó entre papel (endocarpos), a 25º C constante y fotoperíodo de 16/8 h oscuridad/luz. Los resultados mostraron que la remoción completa de endocarpos, el desgaste manual de la zona basal así como la escarificación con ácido sulfúrico durante 6-8 h, son métodos adecuados para romper la dormición, incrementando tanto el porcentaje como la velocidad de germinación, mientras que la escarificación húmeda no produjo efectos sobre la germinación. | The mistol (Ziziphus mistol Grisebach) is a native arboreal specie of Argentina with numerous uses such as feeding, tinctorial, wood, medicinal and melíferous. The fruit of mistol is a drupe that contains a woody endocarp to make difficult the germination of the seeds. The objective of this research was to select the pregerminative treatments to overcome the physical dormancy imposed for the endocarp. The endocarps were treated with physical (complete removal and abrasion of the basal zone), acid and moist scarification. Germination tests were performed top of paper (seeds) and sand or between paper (endocarps) at temperature of 25 ºC constant and photoperiod of 16/ 8 h (dark/ ligth). The results showed that complete removal of endocarps, scarification of the basal zone as scarification with concentrated sulphuric acid during 6-8 hours, are suitable methods in order to break such dormancy, improving both percentage and speed of germination. In contrast, moist scarification was ineffective for to promove germination.

Weeds can be suppressed in the field by cover crop residues, extracts of which have been demonstrated to exert chemical inhibition of crop and weed germination and early growth in bioassays. In this study, two complementary bioassays were developed with soil and mulch material originating from a long-term maize-cover crop experiment to determine the relative physical and chemical effect of rye cover crop residues on weed and maize germination and early growth. This was compared with the effect exerted by residue material from the natural vegetation that developed in the crop stubble during the winter before maize sowing. Germination percentage and early growth of maize and two maize weeds, Amaranthus retroflexus and Echinochloa crus-galli, were assessed in a seed incubator in tilled (green manured) and nontilled (surface mulched) soil, with and without N fertilisation, at various dates after cover crop destruction. Responses were compared to those of the same species in a standard soil without mulch or with an inert poplar mulch. A second bioassay was set up in a glasshouse to determine the effect of different quantities of fresh residue material and additional N fertilisation on emergence speed and percentage and on plant vigour during the first 22 days after cover crop destruction. These results were compared with no-mulch controls and poplar mulch controls. Results of these trials were compared with weed density and biomass that developed in the maize crop sown after cover crop destruction. Soil and mulch chemical and biological properties were determined for material collected in the field at different times after cover crop destruction. Chemical properties of the mulch differed only occasionally between the treatments, but variation in cover crop biomass production led to significantly different soil chemical properties. Although soil total phenolic acid content did not always correlate to weed and maize germination and early growth inhibition, soil microbial activity did. In suboptimal conditions, as is often the case in the field, plant residue material exerted both a physical and a chemical effect on maize and weed emergence and early growth. Nitrogen fertilisation and application timing can give the maize crop a competitive advantage with respect to the weeds, but the final response and the practical consequences depended largely on the weed species involved.

Fruit and seed development in Acer caesium is described for trees growing in montane, temperate forests of the western Himalayas of India. Fruits of A. caesium were harvested during 1997 and 1998 at biweekly intervals after anthesis until maturity. Changes in physical characteristics of samaras and the percent seed germination during developmental stages were recorded. Seeds matured around 210-225 days after anthesis (DAA).With maturation, pericarps and testae turned dark brown in color. This stage coincides with minimum fruit and seed moisture content and maximum germination percentage. Moisture content in both intact samaras and seed (hulled) showed an abrupt decline during the final phase of maturation and stabilized around 12-14% in mature seed. Dry weight accumulation ceased before seed attained physiological maturity. The study revealed that A. caesium seeds underwent a tri-phasic development, that is, growth, reserve accumulation and desiccation.