Seeds In Soil Research Articles

The study of the phytotoxic effects of alkaline detergent and disinfectant Sanimol L

The results of research of phytotoxicity of soils polluted with cleaning and disinfecting products for milking and dairy equipment were presented. Study of the product Sanimol L was conducted compared with the available products on the market, in particular, CircoSuper AF and Sulfohlorantin. It was established that when the content of the studied products in soils was 1.0 mg/kg, 10.0 mg/kg and 100.0 mg/kg, there was a gradual decrease in the mass of the maize stalk, on average by 18.8% and its length by 15.9 % compared to control. When the content of products Sanimol L and CircoSuper AF in soils was 1000.0 mg/kg there was a reducing the mass and length of the maize stalk by an average of 12.5% and 25.0%, respectively. The greatest decrease in the mass of the stem by 59.4% and its length by 62.3% was when the content of product Sulfohlorantin in the soil was 1000.0 mg/kg. After a five-day cultivation of maize seeds in soils with the content of the studied products 1.0 mg/kg and 100.0 mg/kg, it was observed a slight decline in the length of the longest roots by an average of 6.3%. When the content of these products in the soil was 10.0 mg/kg, the length of the longest corn root increased by 8.7%, indicating a stimulating effect on the growth of the root system and the absence of phytotoxicity. When soil was contaminated with products Sanimol L and CircoSuper AF in the amount of 1000 mg/kg, this morphometric index decreased by 12.9% and 21.7%, respectively. The most toxic was the soil with the content of the maximum amount of Sulfohlorantin. In doing so, the length of the longest corn root decreased by 66.9% compared with the control.

User-Centered Redesign of Evidence-Based Psychosocial Interventions to Enhance Implementation—Hospitable Soil or Better Seeds?

User-Centered Redesign of Evidence-Based Psychosocial Interventions to Enhance Implementation—Hospitable Soil or Better Seeds?

Public Health Physician Offers Vivid Parables of Social Inequity

Public Health Physician Offers Vivid Parables of Social Inequity

English

Seed bank (henceforth referred to as SB) refers to viable seed which is present on or in soil and associated with litter/humus. Under different land use/land cover systems and climatic regions, density of seeds in the soil is variable both in space and time. SB density decreases with increasing depth and age of seeds in the soil. Smaller seeds are more easily incorporated, moved to deeper soil layers and persist longer in the soil, whereas large sized seeds without hard seed coats lack persistence in the soil. Moreover, small and elongated seeds are more persistent than large and round seeds. In most vegetation types, grass and herbs have denser seeds in the soil than woody species. Due to shade intolerant properties, density of grasses and forbs are also higher in forest gaps and farmlands than under shade of trees. In most of vegetation types and under medium disturbances e.g. under grazing, density and diversity of species are higher than that of lower and higher disturbance intensities. Tillage practices also have negative impacts on density, composition and abundance of SB. Hence, seeds decline under conventional tillage than under conservational tillage practices. In several studies, seeds in the SB are not similar to above ground vegetation. Similarly, density and diversity of seeds in a SB exceeds that of standing vegetation. Persistence seeds in soil are essential in maintaining individual species and the plant community, conservation of genetic biodiversity and restoration of plant communities of degraded lands after disturbances under harsh environmental conditions, especially in arid regions. As a result, SB characteristics are used to elucidate seed dynamics in various vegetation types. Overall, scientific knowledge of SB is used for land use planning, to make recommendations for future cost effective measures and to establish policies for conservation or restoration programmes. Keywords: Seed bank (SB), dispersal, persistence, restoration, vegetation type.

Ameliorative effects of <i>Daniellia</i>- and <i>Vitellaria</i>-derived biochars on the chemistry of oil-contaminated soils and germination indices of cowpea

The study assessed the effectiveness of biochars derived from Daniellia oliveri and Vitellaria paradoxa in ameliorating waste lubricant oil contaminated soils and improving germination of cowpea seeds. Daniellia oliveri and Vitellaria paradoxa biochars were applied at 0.5 and 1.0 % levels to soils contaminated with 2 % v/w waste lubricant oil (WLO). The unpolluted soil and WLO-contaminated soil without biochar were also used as controls. All treatments in three replicates were arranged in a randomized block design in a screen house. Biochars and soils were analyzed for pH, organic carbon (OC), nitrogen (N), phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg) and total petroleum hydrocarbon (TPH exclusively analyzed for soil). Ten cowpea seeds sown in soils were observed for sprouting from 1 to 10 days after sowing (DAS). Germination percentage and indices were determined from the number of sprouted seeds at 10 DAS. Vitellaria -derived biochar (BV) had higher N, K and Mg than Daniellia -derived biochar (BD). WLO contamination significantly reduced soil P but slightly affected pH, OC and exchangeable cations. Addition of BD and BV reduced TPH and improved soil quality. Oil contamination delayed and reduced cowpea germination by 9.3 % in un-amended WLO-contaminated soil. 1 % BV addition was effective in improving germination velocity and indices of cowpea seeds in oil-contaminated soils.

Winter Grazing and Rainfall Synergistically Affect Soil Seed Bank in Semiarid Area

The soil seed bank is an important ecological component of grassland restoration and renewal. In semiarid regions, grassland restoration and renewal are highly affected by annual variations in precipitation and grazing activity because these variations can affect the composition, density, richness, and diversity of seeds in the soil. This study aimed to characterize and compare these parameters of the germinable seed bank under different stocking rates in a winter grazing system in a semiarid area of China in 2015 and 2016 (dry and near-average rainfall condition, respectively). The composition, density, richness, and diversity of seeds were determined by the method of seedling emergence. The results showed that a total of 18 species belonging to nine families germinated from the soil. Drought significantly reduced the density, richness, and diversity of the soil seed bank, but grazing was able to significantly increase the richness and diversity of the soil seed bank by increasing the richness and diversity of the aboveground vegetation. The similarity between the soil seed bank and aboveground vegetation was influenced by the rainfall conditions: in the dry year, it was higher at the lower stocking rates (0 and 0.4 animal unit months [AUM] ha–1), and in the near-average rainfall condition year, it was higher at the higher stocking rates (0.8 and 1.3 AUM ha–1).

INFLUENCE OF TECHNOLOGY OF SPRING WHEAT CULTIVATION ON THE SOIL SEED BANK OF WEEDS

The work presents the results of the comparative study of the soil seed bank of weeds at crop cultivation in 2 three-fi eld crop rotations (wheat-wheat-oats and wheat-wheat-cabbage crops) using traditional and No-Till technologies. The research was carried out on leached chernozem of central forest-steppe of Priobskiy agricultural landscape area. Before the stationary experiment was laid in 2008, the soil layer of 0-10 cm contained an average of 31800 weed seeds on 1 m2 , and in the layer of 11-20 cm their number was 21200 pieces. Among the 17 identifi ed species, the redroot amaranth dominated. After the fi rst year of crop vegetation, the weed seed bank has grown by 2.2 times with the traditional technology, and by 1.3 times with No-Till technology. By the beginning of the second crop rotation in 2011 in the soil layer of 0- 10 cm there was about the same number of weed seeds with either technology: 41250±2532 pieces/m2 . At the same time, it was noted that the share of bluegrass weeds increased to 25.5-32% with No-Till technology and up to 34.8-35.5% with the traditional one. After the third crop rotation in 2016, the soil seed bank decreased by 5.7 times compared to 2011 with the traditional technology, and by 8.1 times with No-Till technology. The share of bluegrass weeds increased to 67.8% and 47.8%, respectively. The data obtained confi rm that mechanical tillage, which facilitates embedding weed seeds in the soil, ensures their more active germination, further development and distribution. The absence of mechanical tillage, which excludes contact of weed seeds with the soil, as well as the systematic use of herbicides reduce the weed seeds supply in the soil bank with No-Till technology.

Effects of reverse seasonal submersion on the germination and persistence of soil seed banks in hydro‐fluctuation belts

AbstractThe construction of the Three Gorges Dam has resulted in the occurrence of reverse seasonal water‐level fluctuations. The species composition and quantity of riparian soil seed banks collected from four hydro‐fluctuation belts were assessed by simulating different submersion cycles to determine the effects of reverse seasonal water‐level fluctuations on the germination and persistence of soil seed banks in the Three Gorges Reservoir Region. Results showed the number of species that germinated from the soil seed bank decreased with submersion. The number of germinated seeds in soil seed banks after submersion for 7 months in Xingshan, Zigui, Wanzhou, and Zhongxian decreased by 60%, 53%, 57%, and 57%, respectively, relative to the control. The species diversity index and seed density of germinated seeds in soil seed banks also significantly decreased with prolongation of submersion time. Seed density decreased by 93%, 83%, 76%, and 72%, respectively, after 7 months of submersion. Species composition and dominance within the soil seed bank changed over time due to submersion. In general, reverse seasonal submersion negatively impacts the germination and persistence of soil seed banks. The response of soil seed bank germination and persistence to reverse seasonal submersion became the key factor determining the heterogeneity in the spatial distribution of the soil seed bank in hydro‐fluctuation belts due to the large differences in submersion time between areas at various elevations.

Substrate, moisture, temperature and seed germination of the threatened endemic tree Eriotheca vargasii (Malvaceae)

We studied the germination of Eriotheca vargasii (Malvaceae), a poorly known endemic Peruvian Andean tree species characteristic of the dry forests of the Torobamba river valley. We determined seed characteristics, embryo morphology, viability, and assessed the influence of substrate (natural soil and commercially prepared media), temperature (controlled at 25 ºC and at ambient temperature between 18-22 ºC), and moisture (25 % and 50 % field capacity) on seed germination. Although most seeds were ovoid in shape and contained well-developed embryos, only 46% of them were viable. Substrate moisture levels had no influence on germination capacity or rate. In contrast, temperature and substrate type showed strong effects on germination. We observed the highest proportion of germinated seeds in prepared media at both temperatures tested (> 61 %). Furthermore, substrate types also influenced germination rates, with lower values in natural soil. The strongest effect on germination rates was by temperature, enhancing the difference in responses in substrate types. The low proportion of germinated seeds in soil (< 39 %), together with external local stress factors (e.g. grazing impact by herbivores), may be the critical factors contributing to the nearly total absence of seedlings and saplings of E. vargasii in the study area despite abundant seed production.

Contribution of the soil SEED bank to the recovery of a Cytisus oromediterraneus shrubland after fuel reduction treatments

Land managers need scientifically-based information to enable them to select the most appropriate treatments for reduction of high-severity wildfires in shrubland areas. The soil seed bank is known to play a key role in the post-disturbance recovery of shrubland communities, although information about how it is affected by fuel reduction treatments is still scarce. We carried out a combined greenhouse and field study to evaluate the effects of prescribed burning, clearing and mastication on the response of the soil seed bank and vegetation recovery in a Cytisus oromediterraneus (Spanish golden broom) shrubland area in central Spain. We determined the following variables: total seedling density in the greenhouse, broom density (in the greenhouse and field), vegetation cover recovery in the field, species richness (in the greenhouse and field) and similarity index between the floristic composition of the above-ground vegetation and soil seed bank. We also evaluated how the remaining soil organic cover and depth affected seedling emergence after treatments in the field. In addition, we explored the effect of soil thermal regime during prescribed burning on posterior seedling emergence.In the greenhouse experiment, a significantly greater number of seedlings emerged from the soil seed bank samples obtained after burning (1297 seedlings m−2) than from the seedlings obtained before burning (775 seedlings m−2) and after clearing (801 seedlings m−2) or mastication (705 seedlings m−2). The mechanical treatments did not induce any changes in the seedling emergence from the soil seed bank. Species richness in the soil seed bank was not altered by fuel reduction treatments. Post-burning seedling density was not significantly related to any of the soil thermal regime parameters during burning. Soil organic cover after the treatments negatively affected the response of the soil seed bank.The field study revealed no differences between treatments in relation to total vegetation cover, broom cover or grass cover. However, forbs cover was significantly higher in the prescribed burning treatment that is related with the higher density of seedlings of these species measured in the greenhouse experiment. C. oromediterraneus regenerated strongly via sprouting, being the seed germination rate in the field very low. That suggests that the soil seed bank makes little contribution to recovery of this species after fuel reduction treatments, and the same was observed for the remaining plant community.

Effect of Used Lubricating Oil Contaminated Soil on Seed Germination and Early Growth Performance of Wild -Type Legume, Crotalaria retusa L.

Contamination of soil due to used lubricating oil (ULO) has become a common environmental issue, especially in major cities worldwide. This may affect negatively on overall soil quality and may pose a risk to biota. Phytoremediation is a novel green technological approach, which uses plants to remove organic and inorganic pollutants from contaminated soil, air and water and can be usefully used to clean up ULO contaminated soil. Screening of plant species with tolerance to ULO contamination is the most critical initial step in phytoremediation. The aim of the present study is to evaluate tolerance of Crotalaria retusa L. to ULO-contaminated soil. Germination of C. retusa seeds in soils with 1-5% w/w ULO contamination levels was tested according to the ISO method, with five replicates per treatment and ten seeds per replicate. Percentage inhibition of seed germination, root growth and biomass were measured at 48 and 72 hours of incubation. Results showed 100% seed germination in the control (uncontaminated soil) and all treatments indicating high tolerance of tested seeds to germinate in ULO-contaminated soil. However, there was a significant (p<0.05) reduction in root length of seedlings in all treatments above 3% w/w ULO. Therefore, a further pot experiment was carried out using ULO contamination levels of 0.5%, 1%, 1.5%, 2%, 2.5% and 3% w/w ULO. A fully randomized block design (RBD) was employed with 4 replicates per treatment and control. Percentage biodegradation of ULO and shoot height were measured monthly and at the end of a three month exposure chlorophyll a, b, total chlorophyll content, shoot height, root length, shoot system biomass and root system biomass were all measured. Results indicated time-dependent increases in percentage biodegradation of different treatments. At three months, percentage biodegradation was 52.2%, 43.8%, 35.6%, 32.2%, 25.2% and 22.0% for the 0.5-3.0% w/w ULO treatments, respectively. A decrease in growth parameters was observed with an increase in ULO contamination levels. However, the calculated IC50values inferred that the substantial negative effects resulted only on plants grown in soil with contamination levels greater than 2% w/w. There were no significant differences in chlorophyll contents of seedlings under any treatments. Therefore, from the present study we can conclude that C. retusa is able to grow in soils contaminated with ULO up to a level of 2% w/w without showing any negative effects. This result highlights the potential of C. retusa for the phytoremediation of ULO contaminated soil. Keywords: Crotalaria retusa, Phytoremediation, Used lubricant oil Acknowledgements: National Research Council, Sri Lanka (Grant No. 16-144) for financial assistance

Plant traits and population characteristics predict extinctions in a long-term survey of Mediterranean annual plants

Global and local environmental changes lead to frequent plant extinctions many of which occur in man-made habitats such as agricultural fields. Plant traits and site conditions modify risks of extinction, but strength and sense of their effect are not known yet. Here, we present a long-term survey of population sizes for Mediterranean annual plants that we revisited 20 years after their first record to evaluate climate, population size, traits and habitat requirements as drivers of local extinctions. Small populations had an increased probability of extinction in our data-set. Our analyses revealed that seed production and survival of seeds in the soil seed bank decreased extinction rate, whereas plant size increased extinction probability. Mean annual temperature increased extinction rates of annual plants in cereal fields. We discuss these effects as a response to recent and ongoing habitat changes, and discuss how traits may be used to guide conservation practices in the face of local extinctions.

Regenerative Role of Soil Seed Banks of Different Successional Stages in A Saline-alkaline Grassland in Northeast China

Soil seed banks can act as a potential seed source for natural revegetation and restoration. However, in a saline-alkaline grassland, it remains unclear how the stages of vegetation succession affect the characteristics of soil seed banks and the potential of soil seed banks of different successional stages for vegetation restoration. In this study, seasonal changes of the soil seed bank, and seed production and dispersal dynamics along degradation successional gradients were investigated in a saline-alkaline grassland in Northeast China, where the dominant grass during the 1960s, Leymus chinensis was replaced with the secondary successional order of Puccinellia chinampoensis, Chloris virgata, and Suaeda salsa, together with bare patches. It was found that the soil seed bank composition varied according to the changing vegetation and had the highest species richness (7–16) in the climax successional stage, but had a low Sorensen similarity (0.22–0.37) with the aboveground vegetation. There was a high seed density of the soil seed bank (21 062–62 166/m2 in August and December) and also high Sorensen similarity index values (0.47–0.60) in the secondary successional stages of P. chinampoensis, C. virgata, and S. salsa. In bare patches, there were many seeds in the soil seed bank and some seedlings also appeared in the aboveground vegetation, indicating the existence of a persistent soil seed bank. Seed density and species richness differed substantially among the different successional stages, which was related to the reproductive characteristics of the standing plants in vegetation communities. Due to the lack of propagules of perennial species, especially the climax species of L. chinensis, in the soil, the successful restoration of the degraded saline-alkaline grassland was not possible. The study proved that in a degraded saline-alkaline grassland dominated by biennial or annual species, the soil seed bank was important for the revegetation of the current dominant plants, but not for the restoration of the original target species. Therefore, it is necessary to induce seeds or other propagules of the target perennial species.

Seed Germination and Seedling Recruitment Behavior of Winged Sea Lavender (Limonium lobatum) in Southern Australia

AbstractWinged sea lavender [Limonium lobatum(L.f. Chaz)] is emerging as a significant weed of field crops in southern Australia. Several environmental factors affecting germination and seedling recruitment were examined to provide a better understanding of the behavior of its seedbank. At maturity, weed seeds were dormant for a period of around 2 mo, but dormancy was easily broken with scarification or by pretreatment with 564 mM NaOCL for 30 min, which confirms the role of the seed coat in regulating seed germination. Exposure to light significantly increased germination. Seeds were able to germinate over a broad range of temperatures (5 to 30 C), with maximum germination (~92%) at temperatures between 10 and 30 C. At 20 to 25 C, 50% germination was reached within 1.3 to 2 d, and the predicted base temperature for germination of the two populations ranged from 1.4 to 3.9 C. The NaCl concentration required to inhibit germination by 50% was 230 mM, with some seeds capable of germination at salinity levels as high as 480 mM. These results indicated greater tolerance to salinity inL. lobatumthan many other Australian agricultural weed species previously investigated. Seedling emergence was the highest (51% to 57%) for seeds present on the soil surface and was significantly reduced by burial at 1 cm (≤11%) and 2 cm (≤2%), with no emergence at 5 cm. Under field conditions, seedling recruitment varied considerably among the three experimental sites. The level of seedling recruitment was negatively associated with rainfall received at the site, organic carbon (OC) level, and microbial biomass of the soil. Rapid decay of weed seeds in high-OC soils appears to be an important determinant of seedling recruitment in this species and could explain greater occurrence ofL. lobatumon soils with low OC and low microbial activity in low-rainfall areas of southern Australia. Furthermore, many such soils in southern Australia are affected by salinity, which would enableL. lobatumto be more competitive with crops and other weeds present at a site.

Soil management systems and their effect on the weed seed bank

Abstract: The objective of this work was to evaluate the density and composition of the soil weed seed bank when bean, corn, and soybean are cultivated in the no-tillage system (NTS) in rotation with winter cover crop species and in the conventional tillage system (CTS). The experiment was installed in a complete randomized block design with three replicates. The evaluation of the seed bank was performed on soil samples (0-10 and 10-20 cm) in four points of each experimental unit, at 15, 30, 60, and 90 days of cultivation. Bean, corn, and soybean crops were sown in the NTS with different soil cover crops in rotation, as well as in the CTS. The NTS provided a more dense and abundant soil seed bank of the species Gnaphalium spicatum and Oxalis corniculata when corn, soybean, and bean were cultivated. The species Lolium multiflorum showed lower density and less seeds in the soil seed bank when the NTS was adopted. The use of the winter cover crops black oat and cow vetch, cultivated individually or in consortium, resulted in a lower density of weed species, especially of L. multiflorum. The NTS provides a lower density of weed species in the soil seed bank than the CTS.

Effect of management of organic wastes on inactivation of Brassica nigra and Fusarium oxysporum f.sp. lactucae using soil biosolarization

Soil biosolarization is a promising alternative to conventional fumigation. Volatile fatty acids (VFAs) produced in the soil through fermentation of amended organic matter can affect pest inactivation during biosolarization. The objective was to determine how soil amended with organic wastes that were partially stabilized through either composting or anaerobic digestion affected the inactivation of Brassica nigra (BN; a weed) and Fusarium oxysporum f. sp. lactucae (FOL; a phytopathogenic fungus). The mortality of BN seeds in the biosolarized soil was 12% higher than in the solarized soil, although this difference was not significant. However, a significant correlation between BN mortality and VFA accumulation was observed. The number of FOL colony-forming units (CFU) in solarized samples at 5 cm was 34 CFU g-1 of soil, whereas in the biosolarized samples levels were below the limit of quantification. At 15 cm, these levels were 100 CFU g-1 for solarized samples and < 50 CFU g-1 of soil for the biosolarized samples. Amendment addition positively affected the organic matter and potassium content after the solarization process. The organic waste stabilization method can impact downstream biosolarization performance and final pest inactivation levels. This study suggests that organic waste management practices can be leveraged to improve pest control and soil quality. © 2018 Society of Chemical Industry.

STRATEGI PEREMPUAN DAYAK NGAJU DALAM PROGRAM REDD+ DI KALIMANTAN TENGAH

The purpose of this research are to uncover and describing the role and strategy of Kalumpang women in DA-REDD+ program, that facilitated by KFCP. Ecofeminism approach used to finding Kalumpang women strategy, of looking at and treating nature. This approach is also intended to review the extent to which women's Kalumpang involvement in the DA-REDD+ KFCP. DA-REDD+ KFCP pilot project is one of the global framework related to climate change mitigation, saving the environment, by integrating the economics and sustainable prosperity through carbon stocks. The research was conducted in the Kalumpang village, Mantangai Kapuas District of Central Kalimantan Province, with an ethnographic approach. The data obtained by observation, participation observations, documentations, studies secondary data and in-depth interviews with informants who have been. The result showed that women are involved in a small part program, nursery and planting activities (reforestation), especially when filling the soil and planting seeds into polybags.While gender equality issues who was appointed by KFCP in the implementation of the program, has not been able to embrace all levels of society. Strategy undertaken by women Kalumpang also varies confront of the REDD+ program. There are so enthusiastic to follow each set of activities, some are then left and returned at the beginning of the activity.

Decreasing diversity in the soil seed bank after 50 years in Danish arable fields

Side-effects of intensification have raised public concerns. Declining diversity and abundance of wild species and pollution have been reported worldwide. National surveys are necessary to assess the overall effect on the wild flora of the changing management of arable land. We studied how the plant diversity in 40 fields in Denmark has changed over a period of 50 years. Three surveys of the vegetation and the viable soil seed banks were conducted at the same locations in Danish fields in 1964, 1989, and 2014. The same methods were used to estimate the soil seed bank in the ploug layer and to describe the corresponding vegetation in the three surveys. Soil samples were placed in trays in a greenhouse for nine months, and the plants from germinating seeds were identified. Significant changes were found in the viable soil seed bank and the vegetation. A drastic decline of plant species and seeds was observed after the first 25 years. The frequency of species and the number of seeds were reduced considerably from 1964 to 1989. In 2014, the number of seeds in the soil seed bank had increased to the same level as in 1964, whereas the frequency of the species in the vegetation was at about the same level as in 1989. The species in the vegetation deviated partly from those found in the viable soil seed bank as the number of species recorded in both assessments made up only about 50% in all surveys. Relatively few species dominated and have been able to adapt to modern cultivation practice.

Seed production capability of monocotyledonous and dicotyledonous weeds in segetal and ruderal habitats

The main cause of wide presence of weeds in segetal and ruderal habitats is their high seed production capacity. It defined in expressly establishing field experiments, in industrial sowings, in segetal and ruderal habitats of steppe zones of Ukraine. It is determined that average fruitfulness of weeds in ruderal habitats was larger, than in segetal habitats by 3.8 times, and indexes of the maximum fruitfulness – by 4.0 times and reached accordingly 7028 and 9345 pieces, and 20112 and 98337 pieces. In segetal habitats monocotyledonous species of weeds on seed production on conceded dicotyledonous species by 2.9–3.7 times, and on ruderal habitats – by 9.8–10.5 times. Average seed production of monocotyledonous plants made up accordingly 3594 and 5660, and dicotyledonous – 12417 and 55629 pieces of seeds from one plant. Most species of monocotyledonous weeds (56,1 %) formed on one plant from 1 to 10 thousand pieces of seeds, and dicotyledonous weeds (37,9 %) – more than 10 thousand pieces of seeds. In segetal habitats the maximum seed production had families Asteraceae, Brassicaceae, Chenopodiaceae, Lamiaceae, and on ruderal habitats – Asteraceae, Chenopodiaceae, Caryophyllaceae, Apiaceae, Brassicaceae. The highest seed production the most widespread and abundant in sowings and on ruderal habitats had weeds: Convolvulus arvensis L., Ambrosia artemisiifolia L., Cynodon dactylon (L.) Pers., Echinochloa crus-galli (L.) P.Beauv., Eragrostis minor Host, Descurainia sophia (L.) Webb ex Prantl, Cirsium arvense (L.) Scop., Chenopodium album L., Amaranthus retroflexus L., etc. The greatest reserve weed seeds in soil in segetal habitats descended at the expense of species from genera Amaranthus, Galium, Cirsium, Setaria, and on ruderal habitats – Amaranthus, Chenopodium, Plantago, etc. In segetal habitats proof presence of weeds of genera with low seed production was sustained at the expense of their larger number of species, and genera with low number of species – at the expense of high seed production. In ruderal habitats – as at the expense of larger number of species, and their high seed production. The absolute maximum of seed production in segetal habitats have been reached at weeds of genera Amaranthus, Cirsium, Galium – from 3288 to 242266 pieces, and in ruderal habitats – Amaranthus, Chenopodium, Plantago – from 108903 to 1911683 pieces from one plant.

The Effect of Drying of Bread Wheat Seeds Following First Water Uptake on Germination Rate

In semi-arid regions, unfavorable weather conditions are the most important limiting factors for seed germination. The imbibed or germinating seeds in soil can be dried by hot and dry weather. Thus, seeds can largely lose their germination abilities until the next water uptake (called as ‘alatav‘ in Turkish). Before drying, the time of the first water uptake by a seed may be more effective on seed viability at the second water uptake for germination. Therefore, this experiment was conducted to identify the first water uptake rates (WU) of seeds of three bread wheat genotypes (Bezotaja, Kirac and 13-BVD-4) per hour during 50 hours and their germination rates (GR) at the second water uptake after drying the seeds for 3-week in laboratory conditions. The results presented here indicated that the WU and GR were significantly affected by genotypes, imbibition time (T) and their interaction (1% probability level). There was also a significant negative correlation between the WU and GR (r** = –0.9295) at all times studied. Furthermore, the germination ability of Kirac lasted longest (for 38th hour) when the WU reached to 160.24%, and it was followed by Bezostaya and 13-BVD-4 genotypes (63.34% at 37th hour and 152.58% 34th hour, respectively).