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Salinity is a major abiotic stress that inhibits seed germination, plant growth, and consequently the productivity of many important crops such as barley. Expansins are a major group of cell wall-loosening proteins, which play important roles in plant growth and development, and in response to different environmental stresses. In this study, salinity tolerance and changes in the expression of expansin genes in barley were tested. The germination percentage of Yarmouk was 72.3% of the control after 48 hours of salt stress, and that of Rum was 27.4%. Reserve mobilization was 61.6% and 43.6% of the control in Yarmouk and Rum, respectively. The decrease in the total soluble sugars was 0.3, and 0.54 mg. ml−1. g−1 FW in Yarmouk and Rum, respectively. Yarmouk has a higher number of induced expansin genes under salt stress compared to Rum. This indicates a significant role for expansins in the improvement of salinity tolerance of barley. [ABSTRACT FROM AUTHOR]

Rice is an important cereal consumed globally, however, poor germination and non-uniform seedling establishment are major causes of low rice yield in water-limiting arid ecosystems. Seed priming study with KNO3, SA and SiO2 to enhance germination and seedling growth was carried out with the objectives of (1) to determine the effects of seed priming on germination and early seedling growth, and (2) to evaluate effects of seed priming on physiological growth characteristics of rice seedling under drought stress simulated by polyethylene glycol (PEG6000). Under well-watered conditions, rice seeds were primed with concentrations of KNO3 (2.5%, 5%, 10%, 15% and 20%), SiO2 (2.5%, 3%, 3.5%, 4% and 4.5%) and SA (0.5, 1, 1.5, 2, and 2.5 mM). While under drought stress, rice seeds were primed with 2.5% and 5% KNO3; 3% and 3.5% SiO2 and 1 mM and 2.5 mM SA. The results showed that all primed rice seedlings under both well-watered and drought stress conditions had significantly enhanced rice seedling growth parameters of seedling length, plumule length, root length, seedling vigor, seedling biomass and germination index and shorter germination time compared to unprimed controls. However, seed priming with concentrations of 2.5% and 5% KNO3; 3% and 3.5% SiO2, and 1 mM and 2.5 mM SA increased rice seedling growth parameters studied better than other concentrations. However, germination percentage was not significantly affected. Thus, priming of FARO44 rice with these concentrations of chemicals is recommended for fast germination, seedling growth and emergence in arid ecosystems. [ABSTRACT FROM AUTHOR]

Turkey is the widest distribution area of Anatolian black pine (Pinus nigra Arnold. subsp. pallasiana Lamb. Holmboe). It has a distribution of 4.2 million ha which is the second largest area among conifer species having 27% of the plantation areas (540,000 ha) in Turkey. The variation in carbon, nitrogen, carbon/nitrogen ratios, carbon mass, nitrogen mass and optimum germination temperature in the seeds of different Anatolian black pine populations were investigated. The seed material was collected from 10 populations distributed over Turkey. Seeds were germinated under three different temperatures: 15°C, 20°C and 25°C. Seven populations showed highest germination percentages at 15°C, indicating this temperature as optimum for germination. Increasing the temperature, mean germination time values significantly decreased. All evaluated parameters were significantly different among populations. The germination percentages ranged from 49% to 85% while the mean germination times were between 4.6 and 10.1. Carbon and nitrogen ratios ranged between 52%–57.4% and 4.1%–5.0%, respectively. The magnitude of the variance on carbon (%), nitrogen (%), carbon mass, nitrogen mass traits among populations were 31%, 47%, 30%, 25%, respectively. The highest correlation was found between the mean germination time and the combined of carbon mass and nitrogen mass at 25°C (R2 = 0.70). [ABSTRACT FROM AUTHOR]

We explored the temporal effects of fruit consumption on the subsequent seed germination pattern of a fleshy-fruited tree, the Chinese hackberry ( Celtis sinensis). Via nursery-based sowing experiments, we investigated (1) how pulp removal affected seed germination patterns at the different stages of fruit maturation, and (2) how the timing of seed dispersal (August, October, and December) affected the germination patterns of seeds from ripe fruits after the removal of pulp. We found that the removal of pulp from around the seeds of ripe fruit had no effect on the percentage and timing of germination. In contrast, the removal of pulp from seeds of unripe fruits largely reduced the germination percentage. The time of sowing did not affect the germination percentage, whereas the timing of germination was delayed for seeds that were sown later or under shaded environments. [ABSTRACT FROM AUTHOR]

This study investigated the variations in the carbon (C), nitrogen (N), and C/N ratios in the seeds of the Mediterranean Cypress (Cupressus sempervirensL.), a typical forest tree of the Mediterranean Region. The data were gathered from populations distributed across Turkey. We also evaluated the relationship between these variations and germination parameters such as the germination percentage (GP) and mean germination time (MGT). All of the evaluated characteristics demonstrated statistically significant variations among the populations. The GPs were generally low and varied between 14% in Datça and 51% in the Köprülü Kanyon. The MGTs ranged from 14.9 in the Köprülü Kanyon to 18.9 in Marmaris. In addition, the C ratios varied between 46% in Marmaris and 52% in the Köprülü Kanyon, while the N ratios ranged from 1.1% in Beycik and Göksu to 1.8% in the Köprülü Kanyon. Furthermore, we observed a positive correlation between the GP and the C and N contents (R2= 0.51 andR2= 0.49, respectively) but found a negative correlation between the MGT and the C and N contents (R2= 0.56 andR2= 0.32, respectively). Moreover, with regard to the combined C and N seed ratios of the regression models,R2= 0.95 for the GP andR2= 0.87 for the MGT, and the populations with higher quantities of C and N in their seeds had shorter MGTs and higher GPs. [ABSTRACT FROM AUTHOR]

Abstract: The effect of cold and hot aqueous leaf extracts of Lantana camara L. on the germination and seedling growth of Phalaris minor Retz. and Sorghum bicolor L. (Moench) was evaluated. Bioassays indicated that the inhibitory effect of the allelopathic plant on the germination percentage (GP), inhibition percentage (IP) and seed germination index (SGI) of the two recipient weed species was proportional to the concentration of the extract. High concentrations had stronger inhibitory effect than low concentrations that showed no stimulatory effect on both species. Both plumule (PL) and radicle (RL) lengths of the recipient species were affected negatively due to the addition of L. camara extracts and this effect was directly proportional to the concentration and more significant in the case of the radicle of P. minor compared with S. bicolor. Our results suggested that L. camara aqueous extract could be used as a potential allelopathic substance for some weed bio-control. [Copyright &y& Elsevier]

Traditional seed-coating agents are widespread and used in crop protection. However, the coatings can pose an environmental and health hazard. In this study, a novel wheat seed-coating agent was prepared by using natural polysaccharide as the main raw material, which produces bacteriostatic activity and enhances the germination and quality of seeds. The optimum formula of this seed-coating agent was ultimately determined through a series of laboratory experiments and field trials. The results showed that the yield of wheat seeds treated with this novel seed-coating agent was increased by 10% and its material cost was decreased by 15% compared with the conventional toxic seed-coating agent. The toxicity of the novel seed-coating agent was also less than that of the traditional one. Therefore, this wheat seed-coating agent had obvious economic and environmental benefits. [ABSTRACT FROM PUBLISHER]

In the study, a novel soybean seed-coating agent was prepared which used carboxymethylchitosan as the main component, complemented with trace elements, trace fertilizers, penetrating agent, etc, including high ratio of performance-to-price and environmental friendliness. It is efficient and effective, resulting in better seed and crop protection. The influence of coating film on germination energy, germination percentage, seedling growth, antifeedant rate, safety performance, and field growth of the soybean plants was studied in a series of tests and are described in this paper. The effect of increasing yield of this coating agent was tested in experiments conducted in both laboratory and field. Result of the tests showed that the crop yield of soybean seeds coated by the novel seed-coating agent was increased by 17.95%, and at 25.75% less cost, as compared with a traditional soybean seed-coating agent. The antifeedant test of the novel seed-coating agent showed that it had an excellent antifeedant effect and a unique efficacy in pest control as determined by the analysis of feeding area of the leaves and selective antifeedant rate. The acute toxicity test on Sprague-Dawley (SD) rats confirmed that it was safe for the public and meets environmental requirements during usage and disposal so it may show obvious economic and environmental benefits. [ABSTRACT FROM AUTHOR]

We examined the influence of nursery soil cover on germination of Thujopsis dolabrata var. hondai. Seeds were sown under seeding bed conditions: (1) nursery soil (andosol) without soil cover, (2) Kanuma pumice without soil cover, (3) nursery soil with nursery soil cover, and (4) nursery soil with sterilized sand cover. Germination percentages were compared between these conditions. The germination percentage (8.8%) at 10 weeks after sowing under condition 3 was significantly lower than under conditions 1, 2, and 4 (56.8%, 52.0%, and 47.2%, respectively). Of the nongerminated seeds under condition 3, 75.0% were decayed and several fungi were isolated from decayed seeds. An inoculation test of isolated fungi Cylindrocarpon tenue, Cylindrocarpon sp., Fusarium oxysporum, and Botrytis sp. to seeds showed that these fungi caused seed decay. Our results indicated that nursery soil cover may not be suitable for T. dolabrata var. hondai seeds sown in nursery soil because of seed decay by pathogens. [ABSTRACT FROM AUTHOR]

This study was carried out to evaluate seedling responses of 13 ecotypes of Medicago (3 ecotypes), Bromus (4 ecotypes) and Agropyron (6 ecotypes) to seed inoculation with spores of Fusarium solani and F. oxysporum. The ecotypes were from Iran, Russia and Kazakhstan. Seeds of each ecotype were inoculated with either of 2 levels of spores, 60 x 104/ml and 30 x 104/ml for F. solani and 90 x 104/ ml and 45 x 104/ml for F. oxysporum. Seed were grown under laboratory and greenhouse conditions and non-inoculated seed was used as control. Percent and speed of germination, length of root and shoot, and vigor index were measured, and responses of inoculated seed were compared with those of non-inoculated seed of each ecotype. There were significant differences among ecotypes for seedling characteristics due to the infection agents and concentrations. The effect of F. solani and F. oxysporum was more pronounced on speed of germination and vigor index than on germination percentage and other measured characteristics. [ABSTRACT FROM AUTHOR]

An aqueous leaf and root/tuber extracts of three important medicinal plant species (e.g., Bergenia ciliata, Hedychium spicatum and Potentilla fulgens) were tested for their allelopathic effects on germination, radicle and plumule elongation of Amaranthus caudatus, Eleusine coracana, Fagopyrum esculantum, Phaseolus mungoo, Phaseolus vulgaris and Triticum aestivum. The results revealed that: the allelopathic effects increased with increasing concentration of leachats from 2%, 5% to 10%. The susceptible crops were Amaranthus caudatus and Phaseolus mungoo whose germination, redicle and plumule growth were reduced significantly under aqueous extracts of all three medicinal species. The results suggested that all the three species can be grown satisfactorily under traditional agriculture systems of subtropical-sub temperate region if whole plants of these medicinal species are harvested from the agricultural fields and nothing is left in the fields for allelopathic influence. Domesticated cultivation of medicinal plants is clearly a sustainable alternative in order to preserve this wild wealth and increase the farm income of local farmers. [ABSTRACT FROM AUTHOR]