Final Germination Research Articles

SELECTION OF TOLERANT WHEAT VARIETIES DURING THE GERMINATION PHASE

In Morocco, wheat is an indispensable and important crop for the population. Its production in areas affected by salinity is a major problem. The salinity-tolerant variety factor is one of the ways to ensure good productivity. Germination is considered a critical step in the plant's development cycle. Consequently, this study aimed to screen the tolerance to salinity of five varieties of wheat at the germination stage. The experiment was carried out under laboratory conditions, using five concentrations of NaCl 0, 3, 6, 9, and 12g/L. Several parameters were used: the germination rate, the corrected germination, the reduction percentage in germination, the final percentage of germination, the mean daily germination, the germination index, the vigor index of germination, the germination rate index, the velocity coefficient, the average time of germination, the length of coleoptiles and roots. Intraspecific variability of wheat toward salinity was relatively large. The daily germination rate, the final germination, the reduction percentage in germination, the germination rate index, and the mean daily germination proved to be the most appropriate criteria to study the salinity effect on seed germination. Also, an equal hierarchy of sensitivity/tolerance levels during the subsequent development of the coleoptiles and the roots has been adversely affected by increasing salinity. All these parameters describing the germination wheat seeds showed that Rajae variety performs better (relatively tolerant) while; Radia and Kanz varieties are the most affected by salt stress. The results showed that the salt reduces germination by delaying its speed except for Rajae and Amal.

Use of plant growth-promoting bacteria to enhance salinity stress in soybean (Glycine max L.) plants.

The effects of three rhizobacterial isolates namely Pseudomonas fluorescens (M1), Pseudomonas putida (M2) and Bacillus subtilis (M3) were examined to enhance growth and chemical components such as chlorophyll and proline of three cultivars of soybean (Glycine max L.) under two levels of salinity stress (S1 = 200 mM and S2 = 400 mM of NaCl salt). Several morphological and physiological parameters were investigated. The highest mean values of final germination percent (FGP) were registered in cultivar Crawford (95%) followed by Giza111 cultivar (93%) in the presence of P. fluorescens, while, FGP of Clark was 85%. Mean germination time was decreased by the application of P. fluorescens or P. putida in both salt stressed and unstressed traits. All growth parameters were significantly decreased by salinity treatments, particularly at S2. A significant increase in stem length and shoot fresh weight was recorded in plants treated with P. fluorescens. This enhancing trend was followed by the application of P. putida then B. subtilis. Chlorophyll contents and plant soluble proteins were decreased, while proline content was increased as compared with control treatment. Results showed that the salt tolerant cultivar, Crawford, may have a better tolerance strategy against oxidative damages by increasing antioxidant enzymes activities under high salinity stress. These results suggest that salt induced oxidative stress in soybean is generally counteracted by enzymatic defense systems stimulated under harsh conditions. Our results showed that inoculation with plant growth-promoting rhizobacterial (PGPR) alleviated the harmful effects of salinity stress on soybean cultivars. The diversity in the phylogenetic relationship and in the level of genetic among cultivars was assessed by SDS-PAGE and RAPD markers. Among the polymorphism bands, only few were found to be useful as positive or negative markers associated with salt stress. The maximum number of bands (17) was recorded in Crawford, while the minimum number of bands (11) was recorded in Clark. Therefore, the ISSR can be used to identify alleles associated with the salt stress in soybean germplasm.

Screening for Cold Tolerance during Germination within Sweet and Fiber Sorghums [Sorghum bicolor (L.) Moench] for Energy Biomass

Within the project “BIOSEA” funded by the Italian Ministry of Agriculture and Forestry, a preliminary laboratory test was conducted to assess the variability for cold tolerance during germination in 30 cultivars of biomass sorghum, among fiber and sweet types. Seed germination (%) and mean germination time (MGT) were examined at seven constant temperatures (from 8 °C to 35 °C) and base temperature (Tb) and thermal time (θT) for 50% germination were calculated. A wide genetic diversity in the germination response of sorghum was ascertained at 8 °C (CV 45%) and 10 °C (CV 25.4%). At 8 °C, in cultivars of ‘Padana 4’, ‘PR811F’, ‘PSE24213’, ‘PR849’ and ‘Zerberus’, seed germination exceeded 80%. Seeds of ‘Zerberus’ were also the fastest, requiring less than 13 days for final germination at this low temperature. Great differences were found in Tb and θT among cultivars. Tb varied between 7.44 °C (‘PR811F’) and 13.48 °C (‘Nectar’). Thermal time (θT) was, on average, 24.09 °Cd−1, and ranged between 16.62 (‘Nectar’) and 33.42 °Cd−1 (‘PSE24213’). The best combination of the two germination parameters (i.e., low Tb and θT) corresponded to ‘Zerberus’, ‘Sucrosorgo 506’, ‘Jumbo’ and ‘PR811F’. Accordingly, these cultivars are more tolerant to cold stress during germination and, thus, more adapt to early spring sowings in Mediterranean areas (March-April). Cultivars ‘PR811F’ (fiber type) and ‘Sucrosorgo 506’ (sweet type) also combine high cold tolerance with good productivity in terms of final dry biomass, as assessed in open-field conditions (late spring sowing). The genetic variation in the germination response to a low temperature is useful for the identification of genotypes of sorghum suitable to early sowings in semi-arid areas. Selection within existing cultivars for cold tolerance during germination may also contribute to the expansion of biomass sorghum into cooler cultivation areas, such as those of Northern Europe, which are less suitable to this warm season crop.

Accelerating Seed Germination and Juvenile Growth of Sorghum (Sorghum bicolor L. Moench) to Manage Climate Variability through Hydro-Priming

Agriculture in Mali, a country in Sahelian West Africa, strongly depends on rainfall and concurrently has a low adaptive capacity, making it consequently one of the most vulnerable regions to climate change worldwide. Since early-season drought limits crop germination, and hence growth, ultimately yield during rain-fed depending on production is commonly experienced nowadays in Mali. Germination and establishment of key crops such as the staple sorghum could be improved by seed priming. The effects of hydro-priming with different water sources (e.g., distilled, tap, rain, river, well water) were evaluated respectively for three priming time durations in tepid e.g., at 25 °C (4, 8, and 12 h) and by hot water at 70 °C (in contrast to 10, 20, and 30 min.) in 2014 and 2015. Seed germination and seedling development of nine sorghum genotypes were monitored. Compared to non-primed seed treatments, hydro-priming significantly [p = 0.01] improved final germination percentage, germination rate index, total seedling length, root length, root vigor index, shoot length, and seedling dry weight. The priming with water from wells and rivers resulted in significant higher seed germination (85%) and seedling development, compared to the three other sources of water. Seed germination rate, uniformity, and speed were enhanced by hydro-priming also. It is argued that hydro-priming is a safe and simple method that effectively improve seed germination and seedling development of sorghum. If used in crop fields, the above most promising genotypes may contribute to managing early season drought and avoid failure of seed germination and crop failure in high climate variability contexts.

How environmental stressors affect reproductive potential in a saltmarsh plant species Plantago maritima.

We examined whether the presence or absence of different environmental stressors influenced the reproductive potential of a saltmarsh species—Plantago maritima. We focused on total seed output, seed quality, and biomass of progeny. So far, there are no studies trying to answer the question of how different saltmarsh management affects the quality of seed in saltmarsh species. For the purposes of the study, plots subjected to light mowing, light or heavy grazing, trampling, or rooting were designated in three nature reserves in Poland. On each plot, the abundance of infructescences per sq. meter was calculated. Mature infructescences were collected, and their length and number of fruit capsules were measured. The seeds obtained from fruit capsules were weighted and sown in controlled conditions. The germination rate and the final germination percentage were calculated. A representative number of sprouts were grown. After a period of 2 months, the individuals of P. maritima were harvested and their total dry mass was measured. It was found that heavy grazing had the greatest effect on all of the studied characteristics. The presence of this factor resulted in shorter infructescences with a smaller number of fruit capsules. However, this phenomenon was compensated by the higher abundance of infructescences per sq. meter. At the same time, seeds produced by grazed individuals were significantly lighter. Interestingly, intensive trampling by people affected P. maritima individuals in a similar way to heavy grazing, while mowing and rooting had less impact on the considered characteristics. Although a positive correlation between seed mass and germination success was found, the altogether lower seed mass had a negligible effect on germination parameters. Also, the differences in seed parameters did not affect dry mass of obtained progeny grown in laboratory conditions. Synthesis and applications: Different environmental stressors, such as grazing and mowing, have an effect on reproductive potential of a saltmarsh species P. maritima. In the case of habitats created anthropogenically, such as brackish saltmarshes, the role of management is crucial for their conservation. Therefore, searching for the best active protection methods is important. In light of the results obtained, extensive or rotational grazing appears to be the best form of saltmarsh management.

Effect of cashew nut shell liquid on rice growth and methane emission from paddy soil

ABSTRACT Rice cultivation and ruminants are the top two sources of methane (CH4), a potent greenhouse gas, in agriculture. The supplementation of ruminants with cashew nut shell liquid (CNSL), a by-product of the cashew nut industry, can reduce CH4 production through alteration of the rumen microbiota. To assess the effects of CNSL addition and its rate on rice growth and CH4 emissions from a paddy soil, we carried out four experiments. CNSL was added at 0 (control) to 1000 ppm by volume in water or agar. In 3-week in vitro anaerobic incubation of two soils, Fluvisol and Andosol, CNSL significantly (P < 0.05) reduced CH4 production dose-dependently, by 54–61% at 1000 ppm relative to the control. In 7-day seed germination testing, CNSL concentration did not affect the final germination percentage (96–99%). In 19-day early seedling growth, CNSL significantly increased the maximum root length by the same amount at all concentrations. In addition, the number of root hairs notably increased with increasing CNSL concentration. In pot culture of rice, the seasonal total CH4 emission was not affected by CNSL concentration. However, mixing CNSL at 1000 ppm with soil before transplanting tended to reduce the initial 30-day CH4 emission by 41%, whereas addition to surface water after plant establishment had no effect. Rice plant growth and dry matter production in pot cultivation were not affected by CNSL concentration. Altogether, the results indicate that CNSL addition can reduce CH4 production in a flooded paddy soil without major harm to rice growth. It is necessary to develop an effective method for the application of CNSL to paddy fields for enhancing the inhibitory effect of CNSL on soil CH4 emission.

Trichoderma harzianum IS005-12 promotes germination, seedling growth and seedborne fungi suppression in Italian ryegrass forage

Potential of Trichoderma harzianum IS005-12 (TH-IS005-12) to promote seed germination and seedling growth of Italian ryegrass (IRG) forage was evaluated in vitro. Non-desiccated seeds and those pre-harvestly desiccated with total herbicide were treated 25 days (freshly harvested) and 178 days after harvest (mature) with TH-IS005-12 spore suspensions at 0 (T0), 1.8 × 10&lt;sup&gt;7&lt;/sup&gt; (T1) and 1.2 × 10&lt;sup&gt;9&lt;/sup&gt; (T2) spore/mL. TH-IS005-12 promoted the early and final germination and seedling growth in all non-desiccated and desiccated, freshly harvested as well as mature IRG seeds. It was more effective in pre-harvestly desiccated freshly harvested seeds where T2 treatment increased final germination rate for 24%, root number per seedling 1.6-fold and seedling vigour 1.9-fold compared to the untreated control. Moreover, TH-IS005-12 showed an inhibitory activity against seedborne fungi Alternaria alternata and A. ventricosa suppressing their growth in vitro by 82% and 77%, respectively.

English

Optimization of planting dates under any climatic conditions is pre-requisite to improve the yield and quality of the major and minor crops. This study was conducted to evaluate the potential of various mungbean cultivars for morpho-physiological and yield traits under different planting dates. In this pot study twenty mungbean cultivars (MGP-17, DM-D4, C5/95-3-31, C6/95-3-8, 5-63-94, TM-1407, MGP-01, NM-11, MGP-41, 5-63-1, MGP-16, NM20-21, MUNG-88, NM-121-25, RAMZAN, NM-2016, NM-19-19, 1099, NM-51 and NM13-1) were planted on July 01 and August 01. Results revealed that various planting dates significantly affected all the attributes, however, genotypic variation was observed among the cultivars. Delayed planting reduced the stand establishment attributes as mean germination time (1.90%), germination index (3.10%), final germination percentage (7.34%), seedling growth including shoot length (14.88%), root length (23.31%), number of leaves (23.04%), leaf area (5.74%) and number of nodules (13.02%). Likely, gas exchange traits including photosynthetic rate (15.71%), transpiration rate (17.09%), sub-stomatal CO2 concentration (2.39%), stomatal conductance (30.56%), SPAD chlorophyll contents (7.42%) and water use efficiency (3.28%) were also reduced. Among morphological traits, various planting dates also reduced the number of pods per plant (5.04%), length of the pod (5.69%), number of grains per pod (28.68%) and 1000-grains weight (7.05%). Differential responses of all the mungbean cultivars were observed for all the pragmatic traits. Delayed planting significantly reduced the morpho-physiological and yield attributes of all mungbean cultivars. However, two mungbean cultivars (NM-121-25 and NM-2016) relatively performed better with minimum reductions in growth, yield and physiological attributes even in delayed planting while the DM-D4 and TM-1407 were found to be the most sensitive in delayed planting than other tested cultivars. Therefore, mungbean cultivars NM-121-25 and NM-2016 can be sown in late sown conditions to get higher yield. © 2021 Friends Science Publishers

Variability of Seed Germination and Seedling Growth Potential of Ricinodendron heudelotii (Euphorbiaceae) at Fine Scale in Southern of Benin

Ricinodendron heudelotii (Euphorbiaceae) is an oilseed plant with high socio-economic value. Unfortunately, the seed’s tegumentary dormancy causes low germination and severely limits its large-scale spread. Germination and juvenile growth of eleven provenances from Benin and Central African Republics were tested under four different pre-treatments (control, lime scarification, soaking in water for seven days and scarification followed by soaking in water for three days) in order to provide information for use in the reforestation and improvement of R. heudelotii. In a Fischer block with three replicates of ten seeds, the daily and final germination (nine months) was recorded and the cumulative germination rate, average germination time and survival rate were calculated. In addition, total height, diameters at the collar and above the cotyledons, internode length, total number of leaves and seedling internodes were measured quarterly. Germination and growth of juveniles were significantly different between provenances and pre-treatments. The highest germination rate (%) in short duration (d) was recorded with seeds both scarified and soaked for three days in water from Akouho (20%, 42.08 d), CRAPP (36.67%, 18.82 d), Agrimey (33.33%, 18.30 d), Ilikimou (26.67%, 19.94 d) and Woroko (26.67%, 19.25 d) and then lime scarified seeds from Massi (80%, 14.46 d), Itchede (80%, 21.29 d) and Lobaye (60%, 19.11 d). Seedlings from seeds that were scarified and soaked for three days in water showed optimal growth for all traits; Lobaye and CRAPP provenances showed the best height growth (33.22±1.45 and 31.96±1.15 cm) while Massi and Illikimou provenances showed the best growth in collar diameter (1.08±0.06 and 1.11±0.09 cm). Provenances and pre-treatments revealed a discrete variation in germination and growth of R. heudelotii. Scarification on the one hand and scarification coupled with soaking into the water for three days on the other hand, are the best pre-treatments to increase seedling production while the best provenances are Lobaye, Massi and Itchede. These provenances are potential seed sources for Forestation Program in Benin.

The plasticity of the germinative response in the populations of two xeric species inhabiting two contrasting environments of central Mexico

AbstractThe species' germination response evolves based on its population environment; therefore, the responses of each local population evolve independently. We investigated two xeric species from central Mexico, Echeveria gibbiflora and Penstemon campanulatus, the populations of which inhabit two localities (Reserva Ecológica del Pedregal de San Ángel [REPSA] and Parque Ecológico de la Ciudad de México [PECM]) that differ in environmental conditions. For both species and populations, final germination, cardinal temperatures, thermal time and range of temperature for germination (RTG) were determined in seeds that were (a) collected recently, (b) stored in a laboratory for 2 months and (c) reciprocally buried in field conditions for 2 months. The results indicated that for both species, seed population, laboratory storage and temperature were significant for final germination. These responses indicated differences in germination based primarily on the site in P. campanulatus (PECM seeds germinated at higher percentages than REPSA seeds) and the burial site in the REPSA seeds of E. gibbiflora. Cluster and discriminant analyses were conducted for both species, identifying the following significant variables for group treatments: base temperature between the stored and buried seeds of E. gibbiflora and the ceiling temperature between the recently collected, stored and buried seeds of P. campanulatus. The results suggest that instead of seed population, burial (in both species) and laboratory storage (in P. campanulatus) narrowed the RTG. These responses could indicate plasticity in both germination and dormancy in response to environmental conditions experienced in the different habitats, which are crucial for understanding species' adaptive capacity.

The influence of fulvic acid on spring cereals and sugar beets seed germination and plant productivity

The vegetations and fields experiments were conducted in 2017–2018 at Rumokai Experimental Station of the Lithuanian Research Centre for Agriculture and Forestry. The influence of naturally occurring fulvic acids on the germination of spring wheat and barley and sugar beet seeds, development of plants and their yield and quality was investigated. The use of fulvic acids for seed dressing reliably increased the final germination percentage and decreased the mean germination time in spring wheat, spring barley, and sugar beet. It significantly reduced the number of spring wheat sprouts damaged by Fusarium sp. and the number of spring barley sprouts damaged by Fusarium sp. and Microdochium nivale. Fulvic acids increased the length of spring wheat and barley shoots and the air-dry weight of shoots and roots. The use of fulvic acids during plant vegetation reliably increased spring wheat grain yield and sugar beet roots yield, and improved yield quality.Combinations of fulvic acids with pesticides were also investigated. The use of fulvic acids in combination with pesticides used in sugar beet crops improved the action of those pesticides, so it was possible to reduce the rates used, thus reducing environmental pollution.

Nitrogen signals and their ecological significance for seed germination of ten psammophilous plant species from European dry acidic grasslands.

The presented study evaluated effects of potassium nitrate (KNO3), ammonium nitrate (NH4 NO3) and ammonium chloride (NH4Cl) on the germination-related characteristics of 10 species from European dry acidic grasslands. Germination was studied under controlled laboratory conditions. The seeds were subjected to KNO3, NH4 NO3 and NH4Cl in four doses (1, 10, 50 and 100 mM) and to distilled water. Final germination percentage, index of germination velocity and index of germination synchrony were determined. Content of nitrogen in the soil probed from the site of seeds collection was also analyzed. Significant effects of type of the nitrogen compounds and their concentrations were observed. High concentrations of nitrogen-containing salts inhibited completion of germination in almost all species. Helichrysum arenarium and Hypericum perforatum showed preference for NH4+ over NO3‒, whereas Arnoseris minima, Alyssum montanum, Jasione montana and Spergula morisonii showed preference for NO3‒ over NH4+. Centaurea scabiosa, C. stoebe and Hypochaeris radicata had no preference and wide tolerance to the type of nitrogen-containing compound. Echium vulgare showed differential response hard for interpretation. A. montanum and J. montana showed stenotopic behavior in terms of nitrogen-related conditions. It is proposed that nitrogen-rich soil gaps favor establishment of more nitro-tolerant plant species (e.g. C. scabiosa, C. stoebe and H. radicata) as compared to nitrogen-poor ones.

Drought stress affects the germination of four co-occurring

The interactive effect of seasonal temperatures and water potential (Ψ) were examined on the germination of four co-occurring Eucalyptus species (Eucalyptus melanophloia F.Muell., E. pilligaensis Maiden, E. populnea subsp. bimbil L.A.S.Johnson &amp; K.D.Hill and E. viridis R.T.Baker) from the Brigalow Belt South bioregion of New South Wales. These eucalypts are important canopy species, and are a key inclusion for restoring native vegetation to areas that have had significant landscape modification. Final germination, time to first germination, and time to 50% germination were recorded at three alternating temperature regimes for winter (day/night, 19/5°C), spring–autumn (27/12°C) and summer (34/20°C), and eight different Ψ treatments between saturation point (0 MPa) and permanent wilting point (–1.5 MPa) under controlled laboratory conditions. Final germination was highest in all species when seeds were incubated at winter conditions, but spring–autumn and summer temperatures had mixed effects on final germination, depending on the species. Final germination consistently declined with lower Ψ across all temperatures for E. pilliagaensis, E. populnea subsp. bimbil and E. viridis, whereas E. melanophloia displayed a mixed response to temperature and Ψ. No germination occurred when Ψ was lower than –0.25 MPa. Time to first germination and time to reach 50% germination (t50) were lowest at summer temperatures for all species, and all species except E. pilligaensis experienced higher time to first germination and t50 (i.e. slower germination rates) as Ψ decreased from 0 to –0.25 MPa. Our results indicate that all four eucalypts should be treated as drought-sensitive species with a higher probability of field recruitment during cooler and wet conditions.

Physiological potential of green bean seeds treated with Bacillus subtilis

Abstract: The association between beneficial microorganisms and green beans can accelerate establishment in the field. The objective of this study was to investigate the influence of seed treatments in different doses of Bacillus subtilis on the physiological potential of green beans. Seeds from the cultivar Macarrão Baixo were used. The study used a completely randomized design in a double factorial scheme with factor A in the treatments: Pelliculation (PC), Pelliculation with Drying (PCD), Pre-Imbibition (PI), Biopriming (BP); factor B, doses of B. subtilis: 0; 7; 14 and 28 mL of a commercial product.kg of seed-1, and a control. The following treatments were applied: moisture content analysis, first count and final germination, electrical conductivity, length, fresh and dry seedling weight, speed index, and final emergence. Analysis of variance was applied to the data and when significant, it was compared using Tukey’s test and polynomial regression; for the absolute control, orthogonal contrast was applied, with p &lt; 0.05 for all analyses. The treatments did not impair seed viability. Vigor benefited with the use of PI and doses between 16 and 20 mL of p.c.kg of seed-1. PI alone had the best performance. Biopriming, associated with B. subtilis, favors the vigor of green beans.

IN VITRO SEED GERMINATION AND PLANT GROWTH OF “CABEÇA-DE-FRADE” (CACTACEAE)

ABSTRACT The genus Melocactus (“cabeça-de-frade”) comprises 32 species in Brazil, of which M. glaucescens and M. paucispinus are threatened with extinction. The present work evaluated the effects of different concentrations of Murashige &amp; Skoog (MS, MS/2 and MS/4) culture medium and sucrose (15 g L-1 and 30 g L-1) on in vitro seed germination and plant growth of M. glaucescens and the efficiency of sterilization with sodium hypochlorite (NaOCl) on in vitro seed germination and plant growth of M. glaucescens when using seeds and M. glaucescens and M. paucispinus when using apical segment of cladode. In M. glaucescens, the final germination at the different MS and sucrose concentrations varied between 53.5 and 68.1% and the best results for in vitro growth were observed with the lowest mineral salt (MS/2 and MS/4) and sucrose (15 g L-1) concentrations, with lengths of the aerial portion of 9.70 and 10.76 mm, respectively. There was no difference in seed germination and plant growth in chemical and autoclave medium. It is concluded that the use of chemical sterilization with NaOCl at low concentrations of salts (MS/2 and MS/4) and sucrose (15 g L-1) are quite advantageous for producing ornamental plants germinated in vitro and/or apical segment of cladode of M. glaucescens andM. paucispinus, representing a reduction of costs for in vitro cultivation of this species.

Effect of Storage Material and Location on Physicochemical Properties and Nutritional Composition of Stored Bread Wheat in Ethiopia

Postharvest management intervention of wheat grain needs to be examined from technological quality perspectives before its introduction to end-users. Local and improved methods of grain storage cause a lot of losses in terms of physical and Physico-chemical properties. These losses could be improved by providing appropriate storage materials at all agro-ecologies. This study aimed to evaluate the effects of different grain storage materials on the physical and physicochemical properties of stored wheat at different locations. The experiment included three treatments; (Purdue Improved Crop Storage (PICS), polypropylene bags, and Jute bags) at different agro-ecological locations; midland (Debrezeit), lowland (Werer), and highland (Kulumsa). Wheat, Lemu variety was stored in triplicate (25 Kilogram/container) for six months (December 2018 - June 2018) under normal environmental conditions in a randomized complete block design (RCBD), with three replication times Wheat stored in Jute bag at lowland for 6 months had lower final germination percentage, lower gluten index, and higher falling number value. In addition, wheat stored at lowland in jute bag had reduced hardness index value. Meanwhile, wheat stored in a Jute bag at midland for 6 months had a lower final germination percentage, lower hectoliter weight but, insignificant change in the hardness index value. Wheat stored at low land, midland, and highland in a jute bag for 4 and 6 months had shown increment in protein content. Wheat stored at midland in jute bag and PICS for 6 months had lower hectoliter weight and flour yield percentage. Besides, wheat stored at midland in a jute bag for 4 months of storage had higher wet and dry gluten content but, lower gluten index value. This condition may pose a negative influence on the baking performance of flour from wheat stored at lowland and with traditional jut bags. From this study, it can be concluded that PICS bags at all storage sites had Significant effective storage materials to preserve wheat grains. Further investigation, however, is very important to evaluate the influence of these treatments on the end-use qualities including baking quality.

The effects of water depth on the growth of two submerged macrophytes in an in situ experiment

An in situ experiment was designed in which Potamogeton crispus and Hydrilla verticillata were planted in plastic pots 25, 50, 75, 100, 125, 150, 175 and 200 cm underwater to study the effect of water depth on the growth and photosynthetic fluorescence characteristics of the two submerged macrophytes in Lake Gehu, China. The results showed that: 1) Water depth had no significant effect on the germination of both submerged macrophytes. The final germination rate of P. crispus turions was higher than 80%, and the final germination rate of the H. verticillata winter buds was 100%; 2) Water depth affected the survival rate of both submerged macrophytes, and the seedlings at depths of 150, 175 and 200 cm all eventually died; 3) Water depth altered the morphological characteristics of P. crispus and H. verticillata seedlings. (4) Increasing water depth significantly affected biomass (p < .05), with the biomass initially tending to increase, but then decreasing. The root to shoot ratio of both submerged macrophytes decreased with increasing water depth; 5) Chlorophyll contents of P. crispus and H. verticillata increased with water depth from 25 to 150 cm; 6) Water depth had an obvious effect on the photosynthetic fluorescence of submerged macrophytes. The Fv/Fm increased slightly from water depths from 25 to 75 cm, and then decreased significantly when water depth exceeded 100 cm. The ETRmax was significantly different among all treatment groups, and ETRmax was obviously higher at water depths of 25 and 50 cm than at all other depths. These results showed that submerged macrophytes have a limited water depth tolerance range. In Lake Gehu, the recovery of submerged macrophytes will be better in areas with water depths less than 125 cm.

&amp;lt;i&amp;gt;In vitro&amp;lt;/i&amp;gt; Germination and Early Vegetative Growth of Five Tomato (&amp;lt;i&amp;gt;Solanum lycopersicum&amp;lt;/i&amp;gt; L.) Varieties under Salt Stress Conditions

In Senegal, tomato (Solanum lycopersicum L.) cultivation is affected by salinity in many agro-ecological zones. The selection of salt tolerant varieties would be an alternative solution to enhance the production. Thus, germination and growth are studied under axenic conditions for five varieties of tomato subjected to increasing concentrations of NaCl [0, 35, 70 and 105 mM], and supplemented in an MS/2 medium for 30 days. The results reveal that salt negatively affects the evaluated parameters. The Rodeo and Lady Nema varieties have the lowest final germination rates (50%) unlike the Mongal variety (55%). These last two varieties have a decrease of 71.78% and 81.28% in the height of the stem, respectively, in the presence of NaCl at [105 mM] while that of the Rodeo variety is 70%. The Xewel variety has the greatest average number of leaves in the presence of [NaCl 35 mM] (4.95 leaves) and [NaCl 70 mM] (4.77 leaves). The Lady Nema variety records the longest taproot length (2.99 cm) unlike the Rodeo variety (2.25 cm) at [NaCl 105 mM]. The Ganila variety reveals the highest number of secondary roots at the concentrations of [0, 35 and 105 mM] of NaCl with, respectively, 44.12, 29.25, and 4.25 roots. The Lady Nema variety records the highest fresh weight of aerial (0.055 g) and root parts (0.014 g) and the lowest root dry weights (0.0023 g). These results allow to conclude that the Lady Nema and Mongal varieties seem more tolerant, Ganila and Xewel are moderately tolerant and Rodeo is more sensitive to the presence of salt.

Evaluating salinity tolerance in progeny of domestic and wild barley crosses at germination stage

AbstractSalinity is one of the most important challenges facing future global barley (Hordeum vulgare L.) productivity, as it causes major reduction in germination, growth, grain yield, and quality. Screening germplasm for salinity tolerance at germination is vital to breeding programs because germination is the first stage of plant growth and occurs near the soil surface where salt can accumulate in high concentrations. This experiment was conducted to assess salinity tolerance of 249 genotypes (64 diploid (2×) H. vulgare crosses; 174 tetraploid (4×) H. vulgare crosses; and 11 parents) at the seed germination stage. Salinity treatments applied at imbibition included concentrations of 0, 100, 200, and 300 mM salinity and were maintained for 10 d. Analysis of variance of all families indicated significant (P ≤ .001) genotype × salinity interaction for final germination percentage (FG%), corrected germination percentage (CG%), and germination index (GI) at all treatment levels, indicating high genetic variation for salinity tolerance among screened genotypes. The mean of all measured parameters (FG%, CG%, and GI) decreased as salinity concentration increased. These responses can be used to identify genotypes with salinity tolerance at germination. At 300 mM salinity, progenies in 2× Families 1 and 2 were 14.3 and 12.5% saline tolerant, respectively. A total of 29 progenies from 4× families were tolerant to 300 mM treatment at germination. These progenies would have an economic value for improving barley tolerance for salinity.

Effect of abiotic stresses on germination behaviour of Ruta chalepensis

This work aims to highlight the optimal temperature for the seed germination of Ruta chalepensis, an important threatened ethnomedicinal shrub, and assess its germination tolerance against salinity and water stresses as well. For this, the seeds were incubated firstly under different temperatures (5 to 30°C). After that, at 20°C, germination tests were performed under different sodium chloride (NaCl) concentrations (0 to 273.9 mM) and various polyethylene glycol solutions (PEG6000) (0 to -2.20 bar). Final germination percentage, velocity coefficient and latency time were subsequently the germination patterns determined and analysed. The optimum temperature for germination was 15°C, in which the maximum final germination percentage (85%) was noticed; germination fell steadily, however, above and below this temperature and completely ceased at 30°C. Germination behaviour of R. chalepensis seeds under osmotic stress conditions showed a significant effect of both NaCl and PEG6000. Germination decreased whether sodium chloride or polyethylene glycol was increased in the medium (p &lt; 0.05). Moreover, the salinity tolerance threshold was 205.4 mM, equivalent to 16 g L-1 NaCl, while water stress was -1.16 bar, corresponding to 80 g L-1 PEG6000. Beyond these thresholds, germination stopped. Dropping in velocity coefficient and postponing in latency time with increasing both stresses were recorded either. The sensitivity of R. chalepensis seeds to environmental stresses should be taken into account for successful conservation programmes, which should be implemented by sowing seeds and planting seedlings in fresh habitats with sufficient annual rainfall.