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1.
Cuphea (Cuphea viscosissima Jacq. x C. lanceolata W.T. Aiton; PSR23) is a new oilseed crop rich in medium-chain fatty acids similar to tropical palms. Agronomic studies suggest that temperature is a key determinant of cuphea seed yields. However, little is known about the growth and photosynthesis response of cuphea to temperature. The following study is the first of its kind to evaluate cuphea's growth and photosynthesis response to temperature. Cuphea was grown under day/night temperature regimes of 18/12, 24/18, and 30/24 °C and regression analysis was used to assess its responses of growth and photosynthesis and determine their optimum temperature range. Vegetative growth and leaf photosynthesis adapted well over the temperature range studied. However, reproductive growth was more sensitive showing a decline with increasing temperature. Reproductive growth rate was greatest under the lowest (18/12 °C) temperature treatment and declined by 43% at the highest growth temperatures. In contrast, vegetative growth, which was greatest under the 24/18 °C treatment, declined by just 25 and 10% at the lowest and highest temperatures, respectively. Photosynthesis acclimated to temperature by up-regulation of in vivo Rubisco activity with declining growth temperature. Maximum Rubisco activity (Vcmax) in leaves under the 18/12 °C treatment was 76% greater than that of leaves grown at 30/24 °C. Photosynthetic acclimation permitted cuphea to vegetatively grow well over a wide temperature range, but does not explain the sensitivity of reproductive growth to temperature, which will require further research to elucidate.  相似文献   

2.
Cuphea (Cuphea viscosissima Jacq. × C. lanceolata f. silenoides W.T. Aiton, line PSR23) is a new crop being developed in the North Central United States, as an industrial oilseed crop. Cuphea PSR23 seed oil is rich in medium-chain-length fatty acids such as capric acid used to manufacture soaps and detergents. The objective of this research was to determine the time when physiological maturity of cuphea seed is reached and how seed development affects seed moisture, weight, oil content, fatty acid content, germination, and seedling vigor. To evaluate seed development, 2000 cuphea flowers were tagged at anthesis in the field at Prosper, North Dakota in 2004 and 2005. Each flower was tagged when open and the position on the main stem or branch was recorded. Two hundred capsules from the tagged flowers were harvested at 3- to 4-d intervals from 5- to 48-d post anthesis (DPA). Seed weight increased as a function of growing degree days (GDD) and the days from anthesis. Physiological maturity occurred when maximum dry seed weight was attained. Seed weight increases followed the Gompertz function with a R2 = 0.90 (2004) and R2 = 0.95 (2005). All capsules, regardless of their position on the stem, followed the same growth function for seed weight. The maximum dry seed weight estimated by the Gompertz function was 3.61 for 2004 and 3.58 mg seed−1 for 2005. Physiological maturity estimated with a quadratic function occurred at 38 DPA or 270 GDD in 2004. In 2005, physiological maturity occurred at 26 DPA or 265 GDD. As a visual indicator when the capsules split-open seeds inside that capsule are physiologically mature. Seed moisture decreased from 900 g kg−1 at 37 GDD post anthesis to 450 g kg−1 at 319 GDD post anthesis in 2004; however, in 2005 seed moisture decreased from 850 to 81 g kg−1 at 293 GDD post anthesis. Seed germination increased as seed developed and it was 83% when harvested 234 GDD post anthesis. Oil content increased from 98 g kg−1 at 37 GDD post anthesis to 279 g kg−1 319 GDD post anthesis. Fatty acid composition varied throughout seed development. Seed development for 111 GDD and greater had more than 66% of capric acid (10:0). Cuphea should be harvested after 265 GDD post anthesis when most capsules on the main stem are split-open, have attained maximum seed weight, germination, seedling vigor, and oil content.  相似文献   

3.
Applications of ultrahigh CO2 treatments accelerated cuphea (Cuphea viscosissima × C. lanceolata ‘PSR23’) growth and development and aided in seedling establishment. The growth (fresh weight) and morphogenesis (number of leaves and roots and seedling length) were determined in cuphea seedlings exposed to 350, 1500, 3000, 10,000, or 30,000 μmol mol−1 CO2 for 30 days under greenhouse conditions. Greater CO2 levels, especially the ultrahigh levels (i.e. ≥3000 μmol mol−1 CO2) resulted in significantly higher (P ≤ 0.05) fresh weights, leaf numbers, root numbers, and seedling lengths compared to seedlings grown under ambient air (350 μmol mol−1 CO2). For example, cuphea ‘PSR23’ Morris heavy seedlings showed the greatest seedling fresh weight, leaf number, root number, and seedling length when supplemented with 10,000 μmol mol−1 CO2 increasing 607%, 184%, 784%, and 175%, respectively, when compared to seedlings grown without CO2 enrichment.  相似文献   

4.
Lesquerella (Lesquerella fendleri) is a potential alternative crop that is being studied for commercial oilseed production. Understanding the minimum temperatures for germination and seedling growth is important for determining potential areas for lesquerella production. The objectives of this study were to determine the cardinal temperatures for germination and seedling growth, and to screen ecotypes for germination and growth characteristics. A temperature gradient table arrangement was used to observe seed germination over a range of temperatures, and time to germination and shoot appearance. Times to 5 mm root length and 5 mm shoot length were also measured to assess cardinal temperatures for seedling survival and growth. Two different species were examined, L. fendleri and a species we refer to as ‘L. pallida aff.’ because it differed from typical L. pallida plants in chromosome number and in oil quality. We concluded that both germination and growth of L. pallida aff. occurred fastest at 22 °C, whereas L. fendleri germinated earlier at 18 °C, but grew faster at 22 °C. L. pallida aff. also had lower germination than L. fendleri over the range studied. Non-dormant seeds of improved lines of L. fendleri had better performance at temperatures above 22 °C than did unimproved accessions. Lines of L. fendleri selected for high oil content and salt tolerance had similar temperature requirements for germination except for improved line WCL-LO3, the current line being used in production. This line had optimal temperatures 6 °C higher for germination and growth than the other improved lines. Accessions of L. fendleri collected from elevations above 2000 m performed better at warmer temperatures, whereas those collected from elevations below 2000 m tended to perform better at cooler temperatures. Dormant seeds of L. fendleri germinated more quickly at low temperatures and had lower base (<3 °C) and optimal (22 °C) temperatures than non-dormant seeds (>7 °C and 28 °C, respectively). We speculate that this partial dormancy trait allows populations of L. fendleri to exploit a wider range of temperature conditions in the wild in order to thrive in extreme environments.  相似文献   

5.
In the present work, thermogravimetric analysis of 17 organosolv lignin samples was carried out to determine their thermal stability and calculate the kinetic parameters of their pyrolysis. The thermal stability has been estimated by the measurement of the degradation temperature (Td), calculated according to the maximum reaction rate. In addition, degradation temperature at 10% of conversion (T10%) has been obtained in order to compare the initial stability of the samples with Td for all samples. The values of Td are comprised between 262 and 389 °C and the average value is 340 °C. The range for T10% is 251–320 °C and the average value is 270 °C. The ashes content of the samples has been analyzed and all the residues presented values lower than 4 wt%. Kinetic parameters of lignin pyrolysis were calculated by Borchardt–Daniels’ method assuming nth order reaction. The activation energy values obtained are comprised between 17.9 and 42.5 kJ/mol and the average value is 28.1 kJ/mol. These results are in agreement with the bibliography.  相似文献   

6.
Cuphea (Cuphea viscosissima × C. lanceolata ‘PSR 23’) seed contains oils that have industrial application. However, little is known regarding cuphea’s optimal mineral nutritional requirements or responses to inhibiting elements. Oil seed crops often need additional phosphorus (P) to achieve optimal economic yield. Vanadium (V), a commonly occurring soil constituent, interferes with plant P uptake and earlier work showed that V is a factor in lipid metabolism. Hydroponic culture was used to evaluate the relative effect of V on the development of cuphea. Relative root length, root surface area, root weight, and aerial dry weights decreased exponentially as the V concentration increased from 0 to 153 μM. In contrast to field observations of other crops, additions of MgSO4 to increase the Mg:(Mg+Ca) ratio further decreased plant growth by as much 50% at V concentrations greater than 31 μM. Root length was decreased by about 50% of the control when the plant was grown in 153 μM V and relative root area and dry weight were decreased by ≥75%. Increases in V concentration sharply reduced secondary and higher order lateral branching. Reduction in root growth was accompanied by a general chlorotic appearance. The results suggest that readily available V in field situations will result in poor root growth and crop performance. Also, the interaction of V and MgSO4, common in soils in the region, will lead to further reductions in yields in the field.  相似文献   

7.
Kenaf (Hibiscus cannabinus L.) is a potential alternative crop being developed for fiber production. Because planting area varies dramatically from year to year, seed supplies may greatly exceed use so that the excess seed must be stored for one to several years. The objectives of this study were to determine the effect of seed storage duration at 10 °C on germination, vigor, emergence, and yield. Replicated trials were established at Starkville, MS in 1999 and 2000 to evaluate field emergence and biomass yield of kenaf seed from five ‘Everglades 41’ (‘E41’) harvest year seed lots stored at 10 °C in ambient relative humidity for up to 4 years. Germination of these same seed lots under standard (20–30 °C) and cool (20 °C) temperatures, and seed vigor was evaluated over time. Field emergence was the same for the different seed storage durations up to 4 years, but was directly affected by drought conditions for each planted year. Biomass yields ranged from 12.39 to 14.57 Mg ha−1 in 1999 and 16.82 to 18.47 Mg ha−1 in 2000, but were not different between storage durations. Seed germination remained greater than 80% regardless of storage duration. Electrolyte leakage, based on conductivity, was 38–50% less with freshly harvested seed than seed stored for 4 years at 10 °C. However, neither the conductivity nor accelerated aging test were reliable predictors of field emergence. Kenaf seed stored up to 4 years at 10 °C retained germination rates acceptable for commercial use. Neither field emergence nor biomass yield was affected by seed storage duration.  相似文献   

8.
《Field Crops Research》1999,63(2):179-184
Spring barley (Hordeum vulgare L.) is well adapted to the cool and short growing season of interior Alaska but little is known about thermal requirements for development and maturation of barley at such latitudes. Air temperature and barley development were monitored over the course of six growing seasons at Fairbanks (65°N) and Delta Junction (64°N), Alaska. These data were used to assess the base temperature (Tb) in the linear, thermal-unit model using the least variable, x-intercept, and regression coefficient methods. These methods indicated a range in Tb from 0°C to 1.5°C. At a Tb of 0°C, barley required nearly 1100°C d to mature. The phyllochron differed between early and late sowings and averaged 75°C d leaf−1. Sowing date appeared to influence the phyllochron during early vegetative growth due to differences in daylength as well as temperature.  相似文献   

9.
《Field Crops Research》2001,69(1):69-79
Chronological and physiological age of seed tubers have major impacts on potato yields. This paper presents a new, simple and reliable physiological age index (PAI) that considers and reconciles the effects of chronological and physiological age. PAI calculation is based on the haulm killing date of the seed crop (T0) and the end of the incubation period of seed tubers, measured under standardized conditions. The PAI formula is T1/T2, where T1 is the time from haulm killing date (T0) to possible planting date and T2 the time from T0 to the end of the incubation period. The PAI expresses physiological ageing of seed potato tubers within a range from 0 (for physiologically young) to 1 (old) tubers. To test the PAI existing data were re-evaluated and re-elaborated and specific experiments regarding seed origin and storage conditions for different cultivars were performed during 1994–1999. The PAI proved useful in assessing differences due to differences in growing conditions, cultivar, haulm killing, seed origin and storage system, and pre-planting treatments. For example, for cv. Spunta 6 days after haulm killing the PAI was 0.025 and after 100-storage days the PAI was 0.56, 0.52 and 0.49 for seed tubers stored in heaps in the field, at relatively high temperatures, natural diffuse light and a cold (4°C) and ventilated store, respectively. The PAI is related to ground cover duration and yield of the future crop. For a PAI of 0.55 tuber yield was 55 t ha−1, while for a PAI of 0.80 tuber yield was 40 t ha−1. The PAI is easy to measure, non-invasive, objective, reproducible and reliable and could be used for modelling purposes to describe performance of seed tubers.  相似文献   

10.
In this work, the forward extraction of defatted wheat germ protein (DWGP) by reverse micelles was studied. The reverse micellar systems were formed by sulphosuccinic acid bis (2-ethylhexyl) ester sodium salt (AOT), isooctane and KCl solution. The effects of AOT concentration, pH, KCl concentration, extraction time, the amounts of defatted wheat germ flour (DWGF), W0 (the molar ratio of water to surfactant, i.e. W0 = [H2O]/[AOT]) and temperature on the forward extraction efficiency of DWGP were tested. On the basis of single-factor experiments, the optimum extraction was achieved by response surface methodology (RSM). The experimental results lead to the conclusion that the highest forward extraction efficiency of DWGP was reached at the AOT concentration 0.06 g/mL, pH 8, KCl concentration 0.1 mol/L, time 30 min, the amounts of DWGF 0.500 g, W0 25 and temperature 36 °C. Under these conditions, the forward extraction efficiency of DWGP achieved 37%.  相似文献   

11.
This investigation determined the functional properties of protein in Lesquerella fendleri seed and press cake from oil processing. L. fendleri seeds were heat-treated at 82 °C (180 °F) during 120 min residence time in the seed conditioner, and then screw-pressed to extract the oil. Unprocessed ground, defatted lesquerella seeds and press cakes were analyzed for proximate composition and protein functional properties. Protein from unprocessed lesquerella seed showed the greatest solubility (≥60%) at pH 2 and 10 and was least soluble (25%) at pH 5.5–7. Unprocessed lesquerella protein also had high surface hydrophobicity index (So), as well as, excellent foaming capacity and stability, emulsifying properties, and water-holding capacity (WHC) at pH 7. Protein solubility profile of the press cake showed up to 50% reduction in soluble proteins at nearly all pH levels, indicating heat denaturation during cooking and screw-pressing. Foaming capacity of the press cake protein decreased slightly, but foam stability was completely lost. Press cake protein also had markedly reduced values for So, emulsifying properties and WHC, further confirming lesquerella protein’s sensitivity to heat treatment.  相似文献   

12.
Hard red spring wheat (Triticum aestivum cv Butte86) was grown under controlled environmental conditions and grain produced under 24/17 °C, 37/17 °C or 37/28 °C day/night regimens with or without post-anthesis N supplied as NPK. Flour proteins were analyzed and quantified by differential fractionation and RP-HPLC, and endosperm proteins were assessed by two-dimensional gel electrophoresis (2-DE). High temperature or NPK during grain fill increased protein percentage and altered the proportions of S-rich and S-poor proteins. Addition of NPK increased protein accumulation per grain under the 24/17 °C but not the 37/28 °C regimen. However, flour protein composition was similar for grain produced with NPK at 24/17 °C or 37/28 °C. 2-DE of gluten proteins during grain development revealed that NPK or high temperature increased the accumulation rate for S-poor proteins more than for S-rich proteins. Flour S content did not indicate S-deficiency, however, and addition of post-anthesis S had no effect on protein composition. Although, high-protein flour from grain produced under the 37/28 °C regimen with or without NPK had loaf volumes comparable to flour produced at 24/17 °C with NPK, mixing tolerance was decreased by the high temperature regimen.  相似文献   

13.
Cuphea seed oil (CSO) is a potential domestic source of medium chain fatty acids. Although CSO has been obtained using solvent extraction and screw pressing, both methods suffer from disadvantages. Supercritical carbon dioxide (SC-CO2) extraction is a promising alternative extraction technology. It is a very effective means to extract vegetable oils, non-toxic, non-flammable, easy to separate from extracts (i.e., no solvent residues) and there are no solvent disposal costs. This research compared SC-CO2 and soxtec petroleum ether for the extraction of CSO. The CSO yield for the petroleum ether was 29.7% while the SC-CO2 was 28.1%. The free fatty acid content for the SC-CO2 extract was only 8.8% while the petroleum ether extract was 15.0%. The acid values were also much higher for the petroleum ether extract (i.e., 29.8) than for the SC-CO2 extract (i.e., 17.4). The Gardner color of the SC-CO2 extract was determined to be 2+ while the color of the petroleum ether soxtec extract could not be determined because it was very dark due to the presence of chlorophyll. Although the two extraction methods differed slightly in their individual fatty acid compositions, the magnitudes of the differences were inconsequential. This research demonstrated that CSO can be effectively extracted using SC-CO2 at a relatively low temperature and pressure (i.e., 50 °C and 20.7 MPa) to give a very high quality oil. Cuphea seed oil's status as a specialty oil and its corresponding higher value make its extraction using SC-CO2 an economically viable option.  相似文献   

14.
Soluble sugar contents and antioxidant enzyme activities were measured in the embryo of wheat (Triticum aestivum) seeds throughout the desiccation phase of maturation in 2003 and 2004 to investigate whether they were related to seed quality. Whatever the date of harvest after the end of filling, seeds tolerated artificial drying in the ears, and almost all of them germinated at 10 °C whereas they were dormant at 30 °C. Their sensitivity to 5 day accelerated ageing treatment (45 °C, 100% relative humidity) slightly decreased during desiccation. This phase of development was associated with an accumulation of sucrose and raffinose, and an increase in the raffinose/sucrose ratio in the embryo. Artificial drying in the ears resulted in an increase in both sugars, but especially raffinose, and in the maintenance of a high value (around 0.6–0.7) of the raffinose/sucrose ratio. Superoxide dismutase, catalase and glutathione reductase activities did not change markedly in the embryo after mass maturity. They were sufficiently active to maintain malondialdehyde and H2O2 contents at very low levels. No clear relationship existed between the antioxidant enzyme activities and seed quality, whereas seed tolerance to ageing seemed to be related to a high value of the raffinose/sucrose ratio.  相似文献   

15.
《Field Crops Research》1998,59(1):73-79
Kenaf (Hibiscus cannabinus L.), an annual plant of the family Malvaceae, with potential use as a non-wood fiber source is a relatively new crop in Italy where it can be used in the manufacture of paper and pulp products. Cultivars differ markedly in their response to daylength, but stem growth generally declines rapidly following the onset of flowering such that under Italian conditions sowing for fiber production has to be carried out early to allow maximum growth before floral initiation. Sowing is generally delayed until soil temperature exceeds 12°C (approximately the middle of May), and therefore it is important to evaluate genetic diversity in response to low temperature during the germination stage to determine which kenaf cultivars are suited to early sowing. These trials screened various lines to identify those able to germinate at low temperature and therefore suitable for early sowing. The lines were also grown to evaluate photoperiodic requirements and seed yield in the trial environment (Experimental Centre of Rottaia, Pisa, central Italy, 43°40′N latitude;10°19′E longitude). In addition, the germination characteristics of seed obtained here were tested at low constant temperature (8°C) and at alternating 20–30°C temperature. Seed belonging to 15 lines – produced in Australia and selected for tolerance to low temperature – showed high germination percentage at 8°C in comparison with Tainung 2, a cultivar sensitive to low temperature and produced in USA (75 and 12% as overall mean of lines and Tainung 2, respectively). Lines differed significantly in their response to temperature both in germination percentage and mean germination time. Lines showed a wide range of duration of vegetative period. Flowering took place from 31 July to 23 August in most lines, and they are therefore considered early-maturing-types. Lines differed in duration of the period from emergence to seed maturity (from 134 to 187 days), in seed yield per plant (from 0.9 to 27.7 g plant−1), and harvest index (from 0.3 to 16.6%). In some lines, flowering occurred in mid-August and seed filling was then not completed due to low air temperature and unfavourable moisture conditions. Seed produced in central Italy had low quality due to more rapid deterioration and susceptibility to fungal pathogens. Sensitivity to low temperature during germination was greater in most lines and germination percentages were considerably lower than for seed produced in north-eastern Australia. Environmental conditions in central Italy appear inadequate for seed production.  相似文献   

16.
The color (L*, a*, b* parameters), the total phenols content and the global chemical composition (moisture, protein, fat, carbohydrates and ash) of four fresh varieties of olive leaves (Chemlali, Chemchali, Zarrazi and Chetoui) were determined. Fresh olive leaves are characterized by a green color (greenness parameter, a*, varying from ?5.01 ± 0.26 to ?9.14 ± 1.21), an intermediate moisture content (0.85 to 1.00 g/g dry matter, i.e. 46 to 50 g/100 g fresh matter) and a variable amount of total phenols according to the olive leaf variety (from ≈2.32 to ≈1.40 g caffeic acid/100 g dry matter).Fresh leaves were submitted to blanching and/or infrared drying at 40, 50, 60 and 70 °C in order to be stabilized by reducing their moisture contents. The impact of IR drying temperature on some quality attributes (color, total phenols and moisture rate removal) was evaluated. Nevertheless, the effect of prior blanching treatment on the quality attributes of dried leaves is less significant and it depends on the olive leaf variety. The infrared drying induces a considerable moisture removal from the fresh leaves (more than 85%) and short drying durations (varying from ≈162 at 40 °C to 15 min at 70 °C). IR drying temperature showed a significant effect of on total phenols content and the color of the leaves whatever the leaf variety. In fact, total phenols content of dried olive leaves increased if compared to fresh ones. For example, total phenols of Chemlali leaves increased from 1.38 ± 0.02 (fresh leaves) to 2.13 ± 0.29 (dried at 40 °C) and to 5.14 ± 0.60 g caffeic acid/100 g dry matter (dried at 70 °C). IR drying allows preserving the greenness color of fresh leaves and enhancing their luminosity. It could be suggested for preserving olives leaves before their use in food or cosmetic applications.  相似文献   

17.
The feasibility of producing biodiesel from Idesia polycarpa var. vestita fruit oil was studied. A methyl ester biodiesel was prepared from refined I. polycarpa fruit oil using methanol and potassium hydroxide (KOH) in an alkali-catalyzed transesterification process. The experimental variables investigated in this study were catalyst concentration (0.5–2.0 wt.% of oil), methanol/oil molar ratio (4.5:1 to 6.5:1), temperature (20–60 °C) and reaction time (20–60 min). A maximum yield of over 99% of methyl esters in I. polycarpa fruit oil biodiesel was achieved using a 6:1 molar ratio of methanol to oil, 1.0% KOH (% oil) and reaction time for 40 min at 30 °C. The properties of I. polycarpa fruit oil methyl esters produced under optimum conditions were also analyzed for specifications for biodiesel as fuel in diesel engines according to China Biofuel Systems Standards. The fuel properties of the I. polycarpa fruit oil biodiesel obtained are similar to the No. 0 light diesel fuel and most of the parameters comply with the limits established by specifications for biodiesel.  相似文献   

18.
Approximately all simmondsin and oil can be easily removed in one step by repeated extraction with water at 90 °C from ground jojoba seeds. The optimum time and temperature of extraction were respectively 1.5 h and 90 °C. Quantitative analysis of simmondsin was made by HLPC method using adenosine as internal standard.  相似文献   

19.
Soybean oil cake (SOC) has been studied to produce bio-oil in a fixed-bed pyrolysis unit. The effect of pyrolysis parameters on the product yields and compositions were investigated. The highest bio-oil yield of a ca 25.8 wt.% was obtained at 400 °C pyrolysis temperature with a heating rate of 50 °C/min for particles of 0.425–0.600 mm in size. The various characteristics of bio-oil acquired under these conditions were identified. The empirical formula of bio-oil with a calorific value of 33.6 MJ/kg was established as CH1.37O0.15N0.14. The chemical characterization studies showed that the bio-oil obtained from SOC might be a potentially valuable source as renewable fuel and chemical feedstocks.  相似文献   

20.
Cuphea (Cuphea viscosissima Jacq. × C. lanceolata f. silenoides W.T. Aiton, Lythraceae) is an oilseed crop, with medium-chain fatty acids, being developed for the North Central United States for industrial applications in the manufacture of soaps and detergents. Seed germination and seedling emergence of cuphea is often low when compared to the commercial crops. Identification of seed treatments to optimize seedling emergence and stand establishment for cuphea are important for commercial production. The objective of this study was to determine the effect of several fungicide treatments on pure live seed emergence (PLSE) of cuphea. Pure live seed emergence is defined as total seedling emergence adjusted by the germination of the seed planted. Field experiments were conducted at Prosper, ND and Glyndon, MN, in 2005 and 2006. Previous crop rotations were soybean [Glycine max (L.) Merr.]/hard red spring wheat (Triticum aestivum L.), and soybean/hard red spring wheat/sugarbeet (Beta vulgaris var. saccharifera L.) at Prosper and Glyndon, respectively, for both years. The experimental design was a randomized complete block with six treatments and four replicates. Treatments were: no fungicide applied (check treatment), captan, mefenoxam, fludioxonil + mefenoxam, azoxystrobin, and azoxystrobin + mefenoxam. Plant stand was counted and PLSE was calculated 10 to 15 d after seeding at all locations by counting emerged seedlings in the center two-plot-rows and adjusting PLSE for germination. Greenhouse experiments were conducted with soil treatments (pasteurized and non-pasteurized) and the same fungicide seed treatments as the field experiment. Pure live seed emergence, vigor index, and percent of diseased seedlings were recorded. Plant stand and PLSE were significantly greater for the seed treatments that had mefenoxam at the Glyndon, MN, environments, in which the previous crop was sugarbeet. Soil treatment (pasteurization) increased PLSE and vigor index. All fungicide seed treatments improved PLSE and vigor index and reduced damping-off compared to the untreated check. Results suggest that seed treatments including mefenoxam would be beneficial for commercial cuphea production.  相似文献   

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