Ecophysiology of seed dormancy and the control of germination in early spring‐flowering Galanthus nivalis and Narcissus pseudonarcissus (Amaryllidaceae)

Seed dormancy induction and alleviation in the winter‐flowering, moist temperate woodland species Galanthus nivalis and Narcissus pseudonarcissus are complex and poorly understood. Temperature, light and desiccation were investigated to elucidate their role in the germination ecophysiology of these species. The effect of different seasonal temperatures, seasonal durations, temperature fluctuations, the presence of light during different seasons and intermittent drying (during the summer period) over several ‘years’ on seed germination was investigated with outdoor and laboratory experiments. Warm summer‐like temperatures (20 °C) were necessary for germination at subsequent cooler autumn‐like temperatures (greatest at 15 °C in G. nivalis and 10 °C in N. pseudonarcissus). As the warm temperature duration increased, so did germination at subsequent cooler temperatures; further germination occurred in subsequent ‘years’ at cooler temperatures following a second, and also third, warm period. Germination was significantly greater in darkness, particularly in G. nivalis. Dormancy increased with seed maturation period in G. nivalis, because seeds extracted from green capsules germinated more readily than those from yellow capsules. Desiccation increased dormancy in an increasing proportion of N. pseudonarcissus seeds the later they were dried in ‘summer’. Seed viability was only slightly reduced by desiccation in N. pseudonarcissus, but was poor and variable in G. nivalis. Shoot formation occurred both at the temperature at which germination was greatest and also if 5 °C cooler. In summary, continuous hydration of seeds of both species during warm summer‐like temperatures results in the gradual release of seed dormancy; thereafter, darkness and cooler temperatures promote germination. Cold temperatures, increased seed maturity (G. nivalis) and desiccation (N. pseudonarcissus) increase dormancy, and light inhibits germination. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 177 , 246–262.     

Cold tolerance and plant growth promotion potential of Serratia marcescens strain SRM (MTCC 8708) isolated from flowers of summer squash (Cucurbita pepo)

Aim: To determine the cold tolerance and plant growth promotion potential of Serratia marcescens strain SRM (MTCC 8708). Methods and Results: Serratia marcescens strain SRM was isolated from the flowers of summer squash plants, showing no apparent symptoms of yellow vine disease. It was evaluated for growth and plant growth promotion attributes at 15 and 4°C. At 15°C, the isolate was able to solubilize 76·6 μg ml^?1 of P and produce Indole Acetic Acid, IAA (11·1 μg ml^?1). HCN and siderophore production were also detected at 15°C. The isolate retained all the plant growth promotion traits at 4°C. Seed bacterization with the isolate significantly enhanced plant biomass and nutrient uptake of wheat seedlings grown in cold temperatures. Conclusion: Serratia marcescens strain SRM is a promising cold‐tolerant isolate that can significantly influence wheat seedling growth at cold temperatures. Significance and Impact of the Study: This strain can be employed as a bioinoculant in cold temperature conditions.     

From seed to seedling: A critical transitional stage for the Mediterranean psammophilous species Dianthus morisianus (Caryophyllaceae)

Abstract

Seed germination, seedling emergence and seed persistence in the soil were investigated for Dianthus morisianus (Caryophyllaceae), a psammophilous endemic species of Sardinia. Stored and freshly collected seeds were incubated in a range of constant temperatures (5–25°C) and an alternating temperature regime (25/10°C). The effect of seed burial depth on seedling emergence was investigated under controlled environmental conditions. Seed persistence in the soil was verified by in situ experimental seed burials. Seeds of this species were non-dormant, and all seed lots germinated both in the light and darkness, mainly at low temperatures (≤20°C), with a maximum at 15°C (≥95%). Optimal seedling emergence was obtained when seeds were buried at a depth of 1–2 cm, and a declining emergence with increasing depth was observed. D. morisianus was also unable to form a persistent soil seed bank. The fate of the seeds that, after dispersal, do not emerge from the soil in the spring is, therefore, presumably to die before the next favourable growing season.     

Phytophthora cryptogea root rot of tomato in rock woo] nutrient culture. II. Effect of root zone temperature on infection, sporulation and symptom development

The effect of root-zone temperature on Phytophthora cryptogea root rot was studied in tomato cv. Counter grown under winter and summer conditions in rockwool culture. A nutrient temperature of 25°C resulted in increased root initiation and growth, higher in winter-grown than in summer-grown plants. Rhizosphere zoospore populations were greatly reduced at 25°C and above. Growth of P. cryptogea in vitro was optimal between 20°C and 25°C and completely suppressed at 30°C. Encystment was enhanced by increased temperatures above 20°C. Zoospore release in vitro occurred in cultures maintained at constant temperatures in the absence of the normal chilling stimulus. Optimal release was at 10°C; no zoospores were released at 30°C. Inoculated, winter-grown tomato plants maintained at 15°C developed acute aerial symptoms and died after 21 days. Comparable plants grown at a root-zone temperature of 25°C remained symptomless for the 3-months duration of the experiment. Summer-grown infected plants at the higher root temperature wilted but did not die. Enhanced temperature was ineffective as a curative treatment in summer-grown plants with established infection. Aerial symptoms of Phytophthora infection are seen as a function of the net amount of available healthy root. With high root zone temperatures this is determined by new root production and decreased inoculum and infection.     

The effect of gradual changes in temperature on the release of hormones from nerve endings isolated from bovine neural lobes.

Abstract— Homogenates of bovine neural lobe tissue were fractionated by differential centrifugation at 20°C or at 4°C and the distribution of activities of vasopressin and oxytocin among the fractions was compared. The ratio of total hormone to protein (mg) in the homogenate was similar at the two temperatures. At 20°C a much smaller proportion of the total hormone was recovered in the soluble fraction (100,000 g_av supernatant), than at 4°C with a corresponding increase in recovery in the nerve-ending fraction (800–3000 g sediment). Nerve endings isolated at 4°C did not, when incubated, release hormone in response to changes in temperature. Nerve endings isolated at 20°C released hormone when the temperature was reduced below 15°C. Gradual reduction in temperature led to hormone release unaccompanied by lactate dehydrogenase release. Incubation of nerve endings for 10 min at 10°C increased the release of vasopressin and of neurophysin without any increase in lactate dehydrogenase. These results demonstrate that release of vasopressin by cold stimulation occurs by way of exocytosis.     

COMBINED EFFECTS OF ULTRAVIOLET RADIATION AND TEMPERATURE ON MORPHOLOGY,PHOTOSYNTHESIS, AND DNA OF ARTHROSPIRA (SPIRULINA) PLATENSIS (CYANOPHYTA)1

Natural levels of solar UVR were shown to break and alter the spiral structure of Arthrospira (Spirulina) platensis (Nordst.) Gomont during winter. However, this phenomenon was not observed during summer at temperatures of ～30°C. Since little has been documented on the interactive effects of solar UV radiation (UVR; 280–400 nm) and temperature on cyanobacteria, the morphology, photosynthesis, and DNA damage of A. platensis were examined using two radiation treatments (PAR [400–700 nm] and PAB [PAR + UV‐A + UV‐B: 280–700]), three temperatures (15, 22, and 30°C), and three biomass concentrations (100, 160, and 240 mg dwt [dry weight] · L^?1). UVR caused a breakage of the spiral structure at 15°C and 22°C, but not at 30°C. High PAR levels also induced a significant breakage at 15°C and 22°C, but only at low biomass densities, and to lesser extent when compared with the PAB treatment. A. platensis was able to alter its spiral structure by increasing helix tightness at the highest temperature tested. The photochemical efficiency was depressed to undetectable levels at 15°C but was relatively high at 30°C even under the treatment with UVR in 8 h. At 30°C, UVR led to 93%–97% less DNA damage when compared with 15°C after 8 h of exposure. UV‐absorbing compounds were determined as negligible at all light and temperature combinations. The possible mechanisms for the temperature‐dependent effects of UVR on this organism are discussed in this paper.     

Temperature effects on branch and rhizoid production in six species of Fontinalis

Abstract

Branching in Fontinalis occurs primarily in the range of 5 to 15°C and differs among the species. Pool conditions reduce branching significantly among most species and can account for the reduction in growth observed in those conditions.

Data on six species of Fontinalis support the hypothesis that Fontinalis produces more rhizoids in response to temperatures above 10°C and that this production will correspond with the summer season in the north temperate and arctic zones. Since branch production is not inhibited at 15°C and is only slightly reduced at 20°C, it appears that rhizoid production does not interfere significantly with branch production. Since rhizoid clumps often originate at branch innovations, the continuation of branching throughout the summer could aid the moss in attaching during the summer when its chances of success are maximum.     

Prevailing sea surface temperatures inhibit summer reproduction of the kelp Laminaria digitata at Helgoland (North Sea)

The impact of abiotic factors on kelp sporophyte reproduction has rarely been investigated. Laminaria digitata (Hudson) J.V. Lamouroux is one of the few summer fertile Laminaria species worldwide and reproduction is subjected to relatively high water temperatures. We investigated the impact of prevailing summer temperatures (~18°C in August) on the induction of sporangia, meiospore release, and germination at the island of Helgoland (North Sea). At Helgoland, fertile sporophytes are found between April and December with a maximum in late summer. While released meiospore numbers were constant between June and October, germination rates decreased significantly in summer. Short‐term exposure of mature sori to 17°C–22°C induced a significantly higher meiospore release indicating enhancement of sporulation by elevated temperatures. Induction of sporangia on vegetative blade disks was not possible at 20°C, and fertility was only 20% at 18°C–19°C, but it was 100% in cool temperatures of 1°C–10°C. It was shown for the first time in a kelp species that “sporogenesis” is the life‐cycle process with the narrowest temperature window compared to growth or survival of the sporophyte or reproduction, growth, and survival of the gametophyte. We incorporated several parameters (induction time, fertile area, and relative fertility) into a “Reproductive efficiency index.” This indicates that sporogenesis of L. digitata is a cold‐adapted process with an optimum at (5)–10°C. The results show that the population at Helgoland is at its reproduction limit despite the existence of other geographically more southerly located populations.     

Observations on the spore release of Paxillus panuoides

Spore release of Paxillus panuoides was studied in a forest environment at temperatures from ?4 to 24°C and 30 to 100% relative humidity (RH) near Stoneville, Mississippi, from December 1983 through February 1985. Spores were released when temperatures were above 0°C, and daily peaks were usually associated with increased temperatures and decreased RH. In a controlled environment, spore release increased from a temperature of 2°C, to a maximum at 37°C, then ceased at 45°C. Light and RH treatments did not significantly affect spore release. Temperature was determined to be the stimulus for the natural spore release pattern.     

The effect of temperature and wind on the flight activity of cereal aphids

The lower temperature threshold for take-off in Sitobion avenae obtained from an analysis of daily 12·2 m suction trap catches was 16°C. In the laboratory, the take-off threshold for S. avenae was 17·5°C in increasing temperatures, but 19°C when aphids were kept at constant temperatures for a short period of time. The equivalent thresholds were both 20·5°C for Metopolophium dirhodum. Over a period of 16 h no S. avenae took-off from plants at 10°C, 70% at 15°C and all within 16 h at 20°C. It was concluded that suction trap catches can be used to compare the temperature thresholds for take-off of both different species and morphs of a species of aphid. Emigrants of Rhopalosiphum padi, but not of M. dirhodum, took-off at a higher temperature than the alate exules. High winds were found to delay but not inhibit take-off both in the field, and in the laboratory, using both artificial and plant substrates. All aphids eventually flew, even from favourable hosts. It was concluded that adverse weather conditions will delay but not prevent cereal aphid migration in early summer.     

Adaptation to habitat in Aquilegia species endemic to Sardinia (Italy): Seed dispersal,germination and persistence in the soil

Abstract

The autecology of the Sardinian endemics Aquilegia barbaricina Arrigoni et Nardi and A. nugorensis Arrigoni et Nardi were investigated. Peaks of anthesis and seed dispersal were recorded for five populations occurring in two distinct habitats, one riparian and one rupicolous. Germination tests were carried out on seed lots belonging to each population by sowing seeds at 10, 15, 20, 25 and 25/15°C. In addition, seeds were incubated for 2 months at either 25°C (summer), 5°C (winter) or 25°C for 2 months plus 2 months at 5°C (summer followed by winter–SW), and then moved to the germination temperatures. Embryo measurements were taken during pre-treatments and germination. Experimental seed burials were carried out for two populations of each species. Both species dispersed in summer. The population of A. nugorensis occurring on rocky outcrops differed in phenology from both the other A. nugorensis population from riparian vegetation and from A. barbaricina. Both species showed morphophysiological seed dormancy, with <50% germination under laboratory conditions. All riparian populations germinated only after the SW pre-treatment, while the rupicolous population germinated at 25°C, without any pre-treatment. Low germination percentages were observed in the experimental seed burials, suggesting the ability for both species to form a persistent soil seed bank.     

Studies on halimeda. V. effect of temperature on chloroplast migration in this Siphonous green alga&*

Abstract

The effect of temperatures between 15 and 30°C on the daily cycle of chloroplast migration in Halimeda distorta and H tuna was determined from changes in segment pigmentation recorded by time‐lapse videography throughout the experiments. An un‐named opuntioid species was also tested between 20 and 35°C. Both the daily pattern and the amplitude of change in surface pigmentation, which were sustained for at least 5 days at 25°C, were unchanged at the higher temperatures. At 20°C the amplitude was considerably reduced but cyclical changes in surface pigmentation continued to occur throughout the 3‐day low temperature period. However, at 15°C even greater reduction in amplitude was observed together with a reduced rate of paling at the onset of darkness and absence of pre‐dawn re‐greening. Furthermore, at 15°C all daily changes in surface pigmentation had ceased by the second day in H tuna and by the third day in H distorta. These effects of lower temperatures were reversed when the plants were returned to 25°C, although after the 15°C treatment of H tuna the amplitude of the change in surface pigmentation in two of the three replicate plants was small on the first night back at 25°C whilst the third plant lost pigmentation progressively and was completely white, and apparently dead, two days later.     

Seed dormancy,germination and soil seed bank of Lamiophlomis rotata and Marmoritis complanatum (Labiatae), two endemic species from Himalaya–Hengduan Mountains

Seed dormancy and germination characteristics are important factors determining plant reproductive success. In this study, we aimed to explore the characteristics of seed dormancy and germination of two endemic Labiatae species (Lamiophlomis rotata and Marmoritis complanatum) in the Himalaya–Hengduan Mountains. Germination was first tested in the light using freshly matured seeds at 25/15 and 15/5°C, and then again after dry after-ripening. Dried seeds were incubated in the light at a range of constant temperatures (1–35°C). The effects of dark and GA₃ on germination were tested at several different temperatures. Base temperature (T_b) and thermal times for 50% final germination (θ₅₀) were calculated. Seeds were also buried at the collection site to test seed persistence in the soil. Increased final germination after dry after-ripening indicated that the seeds of the two species exhibited non-deep physiological dormancy; however, they exhibited different germination characteristics and soil seed bank types. In L. rotata, GA₃ only promoted germination at 5°C, producing no significant effect at other temperatures. Dark conditions decreased germination significantly at all temperatures. T_b and θ₅₀ values were 0.6 and 82.7°C d. The soil seed bank of this species was classified as persistent. In M. complanatum, GA₃ significantly promoted germination at all temperatures except 15°C. Dark conditions depressed germination significantly at warmer temperatures (20 and 25°C) but had no effect at lower temperatures. T_b and θ₅₀ values were 0.1 and 92.3°C d. The soil seed bank was classified as transient. Our results suggest that the seed dormancy and germination of the two co-existing species share some commonalities but there are also species-specific adaptations to the harsh alpine environment.     

Thermal tolerance and acclimation response of larvae of the sub-Antarctic beetle Hydromedion sparsutum (Coleoptera: Perimylopidae)

Hydromedion sparsutum is a locally abundant herbivorous beetle on the sub-Antarctic island of South Georgia, often living in close association with the tussock grass Parodiochloa flabellata. Over a 4-day period in mid-summer when the air temperature varied from 0 to 20°C, the temperature in the leaf litter 5–10 cm deep at the base of tussock plants (the microhabitat of H. sparsutum) was consistently within the range of 5–7.5°C. Experiments were carried out to assess the ability of H. sparsutum larvae collected from this thermally stable environment to acclimate when maintained at lower (0°C) and higher (15°C) temperatures. The mean supercooling points (freezing temperature) of larvae collected in January and acclimated at 0°C for 3 and 6 weeks and 15°C for 3 weeks were all within the range of −2.6 to −4.6°C. Larvae in all treatment groups were freeze tolerant. Acclimation at 0°C significantly increased survival in a 15-min exposure at −8°C (from 27 to 96%) and −10°C (from 0 to 63%) compared with the field-fresh and 15°C-treated larvae. Similarly, survival of 0°C-acclimated larvae in a 72-h exposure at −6°C increased from 20 to 83%. Extending the acclimation period at 0°C to 6 weeks did not produce any further increase in cold tolerance. The concentrations of glucose and trehalose in larval body fluids increased significantly with low temperature acclimation. Larvae maintained at 15°C for 3 weeks (none survived for 6 weeks) were less able to survive 1-h exposures between 30 and 35°C than the 0°C-treated samples. Whilst vegetation and snow cover are an effective buffer against low winter temperatures in many polar insects, the inability of H. sparsutum larvae to acclimate or survive at 15°C suggests that protection against high summer temperatures is equally important for this species. Accepted: 2 August 1999     

Effect of maturation conditions on light and temperature requirements during seed germination of Citrullus colocynthis from the Arabian Desert

• Seed germination of Citrullus colocynthis, as in many other species of Cucurbitaceae, is inhibited by light, particularly at low temperatures. Germination response to light and temperature has been attributed to day length and temperature during seed maturation. This study assessed the effects of these factors on the germination response of C. colocynthis to temperature and light quality.
• Ripe fruits were collected from natural habitats during December and February and germinated at three temperatures (15/25, 20/30 and 25/35 °C) in five light treatments (dark, white light and Red:Far Red (R:FR) ratios of 0.30, 0.87 and 1.19). Additionally, unripe fruits were also collected from natural habitats and completed their maturation in growth chambers under different day lengths (6, 16 and 24 h of darkness) at 10/20 °C, and in darkness at both 10/20 °C and 25/35 °C. Mature seeds of the different treatments were germinated in the same five light treatments at 15/25 °C.
• Germination was significantly higher in the dark than that in any light treatment. Seeds matured at higher temperatures (i.e. seeds from the December collection and those matured at 25/35 °C) had significantly higher germination than those matured at lower temperatures (i.e. seeds from the February collection and those matured at 10/20 °C). Dark germination was significantly higher for the December collection than for the February collection. Seeds of the two collections germinated in the dark only at 15/25 °C. However, seeds matured in a growth chamber at 10/20 °C in darkness germinated at 15/25 °C in all light treatments, except for the R:FR ratio 0.30. Seeds of the different treatments failed to germinate in FR‐rich light.
• This study demonstrates that both temperature and day length during seed maturation play significant roles in the germination response of C. colocynthis. Additionally, the dark requirement for germination is likely beneficial for species with the larger seeds, such as C. colocynthis, which produce bigger seedlings that are able to emerge from deep soils and are competitively superior under dense vegetation and resource‐limited conditions.

     

Survival of Heleomyza borealis (Diptera, Heleomyzidae) larvae down to − 60°C

Heleomyza borealis Boh. (Diptera, Heleomyzidae) overwinters as larvae in Arctic habitats, where they may experience winter temperatures below ? 15°C. The larvae freeze at c.? 7°C but in acclimation experiments 80% survived when exposed to ? 60°C. Of the larvae exposed to between ? 4 and ? 15°C, only 3% pupated. However, when cooled to ? 20°C this increased to 44%, with 4% emerging as adults. Larvae maintained at 5°C contained low levels of glycerol, sorbitol and trehalose, which did not increase with acclimation to low temperatures. However, levels of fructose increased from 6.1 μg mg^?1 fw in control animals to 17 μg mg^?1 fw when exposed to ? 2°C for 1 week. Larval body water (2.2 ± 0.1 g/g dw, mean ± SD, n = 100) and lipid content (0.22 ± 0.002 g/g fw, mean ± SE) showed no significant change during acclimation to low temperatures. Larvae maintained at a constant 5°C survived for over 18 months with little loss of body mass (from 7.5 ± 1.2 to 7.0 ± 1.2 mg fw, mean ± SD, n = 20), but none pupated. Heleomyza borealis larvae appear to feed and grow until they reach a body mass of about 7.5 mg and then become dormant. They remain in this state until they experience a low temperature stimulus (< ? 15°C) followed by a warm period (≈ 5°C). This ensures that the larvae pupate and adults emerge in early summer, allowing the maximum growing period before the following winter. Heleomyza borealis are adapted to survive long winters in a dormant larval state. They have a low metabolic rate, can conserve body water even at subzero temperatures but do not synthesize large quantities of cryoprotectants.     

L'“Artemisia Verlotorum„ lamotte a roma e in altre località italiane

Acacia saligna is a phanerophyte native to Australia; it was introduced in the 1950s in Sardinia (Italy) for afforestation mainly in coastal areas and at present it is considered naturalized, becoming invasive in sand dune habitats. Seed biology is one of the most important factors contributing to the invasion success of Australian acacias, for this reason the germination ability is an important issue when trying to clarify the invasion dynamics of A. saligna. Germination tests were conducted at the BG-SAR, testing the effect of different temperatures and percentages of NaCl, on seeds belonging to five accessions from four populations of two coastal habitat types. The optimal temperature range for seed germination was 15–20°C; the increase of salt caused a decrease in the final germination percentages. At 1% of NaCl concentration, germination fell at 25–30°C and at 2% it was relatively low (below 40%) and occurred almost only at 15°C. This work represents a contribution to the knowledge of the seed ecology and germination behaviour of the species, providing new data on the interpopulation and interannual variability, and relating them to the invasion dynamics of A. saligna in the coastal Mediterranean habitats.     

Increasing temperature decreases the predatory effect of the intertidal shanny Lipophrys pholis on an amphipod prey

Interactions between Lipophrys pholis and its amphipod prey Echinogammarus marinus were used to investigate the effect of changing water temperatures, comparing current and predicted mean summer temperatures. Contrary to expectations, predator attack rates significantly decreased with increasing temperature. Handling times were significantly longer at 19° C than at 17 and 15° C and the maximum feeding estimate was significantly lower at 19° C than at 17° C. Functional‐response type changed from a destabilizing type II to the more stabilizing type III with a temperature increase to 19° C. This suggests that a temperature increase can mediate refuge for prey at low densities. Predatory pressure by teleosts may be dampened by a large increase in temperature (here from 15 to 19° C), but a short‐term and smaller temperature increase (to 17° C) may increase destabilizing resource consumption due to high maximum feeding rates; this has implications for the stability of important intertidal ecosystems during warming events.     

A comparative study of development and demographic parameters of <Emphasis Type="Italic">Tetranychus merganser</Emphasis> and <Emphasis Type="Italic">Tetranychus kanzawai</Emphasis> (Acari: Tetranychidae) at different temperatures

We investigated the effect of temperature on development and demographic parameters such as the intrinsic rate of natural increase (r _m) of the two spider mite species Tetranychus merganser Boudreaux and T. kanzawai Kishida at eleven constant temperatures ranging from 15 to 40°C at intervals of 2.5°C. Both male and female T. merganser and T. kanzawai completed development from egg to adult at temperatures ranging from 15 to 37.5°C. The longest developmental duration of immature stages was found at 15°C and the shortest developmental duration was found at 35°C for both species. Using linear and non-linear developmental rate models, the lower thermal thresholds for egg-to-adult (female and male) and egg-to-egg development were estimated as 12.2–12.3°C for T. merganser and as 10.8°C for T. kanzawai. The highest developmental rates were observed at around 35°C, whereas the upper developmental thresholds were around 40°C for both species. In fact, at 40°C, a few eggs of either species hatched, but no larvae reached the next stage. The r _m-values of T. merganser ranged from 0.072 (15°C) to 0.411 day⁻¹ (35°C), whereas those of T. kanzawai ranged from 0.104 (15°C) to 0.399 (30°C). The r _m-values were higher for T. kanzawai than for T. merganser at temperatures from 15 to 30°C, but not at 35°C (0.348 day⁻¹). Total fecundity of T. merganser was also higher than that of T. kanzawai at 35°C. These results indicate that higher temperatures favor T. merganser more than T. kanzawai.     

Growth promotion of wheat seedlings by <Emphasis Type="Italic">Exiguobacterium acetylicum</Emphasis> 1P (MTCC 8707) a cold tolerant bacterial strain from the Uttarakhand Himalayas

Exiguobacterium acetylicum strain 1P (MTCC 8707) is a gram-positive, rod-shaped, yellow pigmented bacterium isolated from soil on nutrient agar plates at 4°C. The identity of the bacterium was arrived on the basis of the biochemical characterization, BIOLOG sugar utilization pattern and sequencing of the 16S rRNA gene. It grew at temperatures ranging from 4 to 42°C, with temperature optima at 30°C. It expressed multiple plant growth promotion attributes such as phosphate solubilization, indole acetic acid (IAA), siderophore and hydrogen cyanide (HCN) production, differentially at suboptimal growth temperatures (15 and 4°C). At 15°C it solubilized phosphate (21.1 μg of P ml⁻¹ day⁻¹), and produced IAA (14.9 μg ml⁻¹ day⁻¹) in tryptophan amended media. Qualitative detection of siderophore production and HCN were possible at 15°C. At 4°C it retained all the plant growth promotion attributes. Seed bacterization with the isolate, positively influenced the growth and nutrient uptake parameters of wheat seedlings in glass house studies at suboptimal cold growing temperatures.