Acclimatization Treatment Research Articles

Seeding and Acclimatization for Aerobic Processing of Restaurant Wastewater with Sequencing Batch Reactor

Restaurant wastewater has a relatively high organic matter content, so it needs to be treated to meet the specified quality standard. One of the technologies that can be used in restaurant wastewater treatment is Sequencing Batch Reactor (SBR) technology. The purpose of this study is to set up an aerobic SBR system with seeding and acclimatization treatments to reduce the amount of organic matter in restaurant wastewater when a shock load occurs. The research was done using wastewater from a restaurant in Bandung and activated sludge from the food industry in Bogor as seeds for microorganisms. In this study, the seeding process was carried out by introducing 25% activated sludge and 75% nutrients into the reactor, and the acclimatization process was carried out by introducing a specific ratio of nutrients and wastewater into the reactor gradually until the waste concentration reached 100%. The parameters tested were COD, MLVSS, DO, pH, and temperature. During the seeding procedure, the initial COD value of 3,200 mg/L declined. It began to stabilize on the seventh day, with a COD value of 1,080 mg/L. The COD removal reached a relatively stable condition in the acclimatization process starting on day 2, where COD decreased from the original 1,280 mg/L to 480 mg/L.

Growth of Eucheuma cottonii seaweed from tissue culture with different time acclimatization in Hurun Bay

Constraints on the seaweed culture in Indonesia until now still rely on seeds obtained by vegetative propagation and have poor quality, which often causes a decrease in genetic variability. Planting seaweed seedlings from tissue cultures that have been acclimatized in a greenhouse laboratory is believed to improve the quality of the seaweed seeds. This research aimed to observe the growth of tissue culture acclimatized Eucheuma cottonii seaweed seedlings to different rearing times in greenhouses applied to floating raft cages. This study used a completely randomized design (CRD) with three treatments and three replications. Acclimatization treatment was conducted for 2 weeks, 4 weeks, and 6 weeks. Seaweed seedlings acclimatized in the greenhouse are reared on bamboo floating rafts in the sea, with an initial weight of 5 grams each. The length of maintenance at sea is 28 days. The resulting daily growth rate in two-week acclimatization was 2.92%, the four-week treatment was 2.93%, and the six-week treatment was 2.57%. in raising seedlings at sea, the highest daily growth rate value was in the four-week treatment of 7.25%, followed by the two-week treatment of 7.11% and the six-week treatment of 6.43%.

Differences in Early Season Emergence and Reproductive Activity Between Spathius agrili (Hymenoptera: Braconidae) and Spathius galinae, Larval Parasitoids of the Invasive Emerald Ash Borer (Coleoptera: Buprestidae).

Both Spathius agrili Yang and Spathius galinae Belokobylskij and Strazanac are host-specific parasitic wasps introduced for biological control of emerald ash borer in North America. Spathius agrili is native to northeastern China and S. galinae comes from a more northern, colder climate in the Russian Far East. Their origin may lead to differing abilities to adapt to climate and their host in North America. We conducted both field and laboratory experiments to determine the timing of early season emergence and synchronization of each parasitoid species to their host in the United States, and if manipulating prerelease conditions could affect emergence time. A cold acclimatization treatment prior to parasitoid emergence was assessed and compared with untreated control group reared with standard rearing protocols. Stands of naturally emerald ash borer-infested ash were sampled at two locations in Virginia throughout the experiment to determine when the parasitoid-susceptible life stage (third to fourth instar) occurred. Untreated S. galinae emerged approximately 2 wk earlier than any other cohort, whereas cold acclimatized S. galinae emerged later than any other cohort. Emergence time of S. agrili was unaffected by cold acclimatization. Cold acclimatization treatment did not affect the parasitism rate of either species, nor did it have multigenerational effects. Emergence time of the subsequent generation of S. agrili was delayed by cold acclimatization treatment, whereas S. galinae experienced no multigenerational effects. At Virginia field sites, susceptible EAB larvae were present during the emergence time of all four groups of parasitoids. Untreated S. galinae had the least overlap with any susceptible EAB larvae.

Rapid cold hardening response in the predatory mite Neoseiulus californicus

We investigated the rapid cold hardening (RCH) response in the predatory mite Neoseiulus californicus (McGregor) (Acari: Phytoseiidae). On direct exposure, ≤2 % of adult females survived -10 °C for 2 h. However, when acclimatized first at 5 °C for 1 h, 75 % of females survived. RCH could also be induced by acclimatization at 30 °C for 2 h or anoxia (oxygen-free nitrogen) for 1-2 h. All immature stages showed enhanced survival when acclimatized at 5 °C for 2 h before exposure to -10 °C. Acclimatization at 30 °C induced RCH only in eggs and deutonymphs, and anoxia was effective for eggs, larvae, and deutonymphs. The variability among immature stages may be attributed to the cost associated with the acclimatization treatments. Our findings suggest that RCH may promote the survival of N. californicus during unexpected changes in temperatures, and can be an important feature particularly when this natural enemy is introduced to non-native environments.

Significant improvement of salt tolerance with 2-day acclimatization treatment in Elaeagnus oxycarpa seedlings

To enhance the salt tolerance of Elaeagnus oxycarpa, an orchard tree widely used for revegetation in northwest China, we applied a stress acclimatization treatment to hydroponically grown seedlings for 2 days by adding polyethylene glycol (PEG) to the culture solution. The seedlings were then transferred to culture solution containing 300 mM NaCl for 2 weeks to evaluate their salt tolerance. All seedlings pretreated with 20% (w/v) PEG survived until the end of the NaCl treatment, while most seedlings without the acclimatization treatment died. The photosynthetic rate and chlorophyll fluorescence of the un-pretreated seedlings were dramatically decreased by salt stress; however, photosynthesis was maintained and chlorophyll fluorescence was almost unchanged in the seedlings subjected to acclimatization pretreatment with 20% PEG. The acclimatization treatment significantly increased fructose, glucose, and Ca 2+, and slightly increased maltose, K +, Mg 2+, and β-alanine betaine in leaves. We conclude that 2-day stress acclimatization treatment can improve salt tolerance of E. oxycarpa seedlings enough to adapt them to a lethal concentration of NaCl.

STUDIES ON PRE ACCLIMATIZATION TREATMENTS TO IMPROVE POST ACCLIMATIZATION SURVIVAL IN STEVIA (STEVIA REBAUDIANA BERT.)

The special conditions during in vitro culture result in the formation of plantlets of abnormal morphology, anatomy and physiology. After ex vitro transfer, these plantlets might easily be impaired by sudden changes in environmental conditions, and so need a period of acclimatization to correct the abnormalities. The large number of plants lost or damaged during acclimatization often restricts application of micropropagation for rapid multiplication of plants. Acclimatization continues to be a major bottleneck in the micropropagation of stevia too with lower success reported. In the present investigation, pre acclimatization treatments such as dipping the explants in high concentration cytokinin (benzyl adenine, BA) before culture and use of growth retardants that inhibit gibberellin biosynthesis (ancymidol) in culture were used to study their effect on post acclimatization survival of micropropagated plantlets. Dipping of explants in high concentration BA resulted in an increase of number of multiple shoots and number of leaves per shoot and survival percentage after acclimatization. But a significant reduction was noted in internode length and shoot height. Dipping the explants with 100 mg/L BA before culture resulted in highest survival after acclimatization. Ancymidol reduced the length of the shoot, number of leaves, and internodal length considerably. Survival percentage increased with concentration until 3 mg/L ancymidol and reduced with further increases in ancymidol concentration. This reduction might be because the excessive reduction in growth characteristics, which made the plants too fragile to withstand the pressure of acclimatization. The use of 3 mg/L resulted in a higher number of multiple shoots and average growth parameters and a better survival percentage (75.80% - increase of 25.29% over the control - 60.50%).

Testing differences in methods of preparing moss samples. Effect of washing on Pseudoscleropodium purum

When terrestrial mosses are used to study the risks associated with the accumulation of airborne pollutants, samples must be washed to remove deposits adhering to the surface. Here, we studied the effects of washing the samples as well as of freezing, drying, and acclimatization treatments. The differences between the concentrations of Al, As, Cd, Cr, Cu, Fe, Hg, K, Ni, Pb, Se, V, and Zn in washed and unwashed samples were significant, and therefore, it would not be valid to combine or compare the data corresponding to samples treated thus. We also investigated whether there were significant differences in the concentrations of various metals and metalloids yielded from samples subjected to different treatments prior to washing (freezing, drying, acclimatization after drying, and acclimatization only), while also considering possible effects of the level and type of contamination and the weather conditions. For many of the elements, we found significant differences that depended on both the levels of contamination at each sampling site and the weather. As these differences may be due to changes in the contents of the different cellular fractions, the sequential elution technique was applied to determine the locations of Cu, K, and Zn. The freezing and drying procedures were rejected because they alter the permeability of the membranes and lead to underestimation of the concentrations of elements. With the acclimatization procedure, particles of some elements adhere to the surface, making this option unsuitable when a description of bioconcentration is required. Taking into account these limitations and the lack of an optimal procedure, acclimatization after drying is proposed as the best option for harmonizing the method.

Selection of thermotolerant yeast strains Saccharomyces cerevisiae for bioethanol production

The simultaneous saccharification and fermentation (SSF) process of lignocellulosic materials requires the utilization of microorganisms capable of working at high temperatures. The selection of Saccharomyces cerevisiae strains able to ferment sugars obtained from lignocellulosic material at temperatures above 35 °C with high ethanol yield has become a necessity. In this work, 11 S. cerevisiae strains were screened for their ability to grow and ferment glucose in a temperature range of 35–45 °C. All the strains grew (in agar plates) at 35 and 40 °C, only two strains grew at 42 °C, and no strain grew at 45 °C. The yeasts were placed in a liquid medium, and incubated at 35, 40 and 42 °C. Glucose-to-ethanol conversion yield was between 50% and 80% of the theoretical value. Strains that produced at least 70% of the theoretical ethanol yield were submitted to two acclimatization treatments. One pure yeast strain was isolated (IR2-9a). For bleached kraft pulp as well as organosolv-pretreated Pinus radiata chips, the ethanol yields by SSF using the IR2-9a strain were higher than those obtained using the control yeast.

Monitoring the stability of Rubisco in micropropagated grapevine (Vitis vinifera L.) by two-dimensional electrophoresis

Plants cultured in vitro suffer from several physiological and biochemical impairments due to the artificial conditions of growth, namely the composition of the heterotrophic media. Upon transfer to ex vitro, the higher irradiances, compared to in vitro, can lead to oxidative stress symptoms, which can be counteracted by CO2 concentrations above atmospheric levels. Here we analyse the stability of Rubisco in in vitro grapevine plantlets, and after transfer to ex vitro under four acclimatization treatments: low irradiance (LL, 150 micromol m(-2)s(-1)) and high irradiance (HL, 300 micromol m(-2)s(-1)) in association with CO2 concentrations of 350 (LCO2) and 700 (HCO2) microL L(-1). Proteins were separated with SDS polyacrylamide gel electrophoresis and two-dimensional electrophoresis and Rubisco degradation peptides were analysed by immunoblotting with anti-LSU antibodies. These degradation products were present in the leaves of plantlets under both in vitro and ex vitro treatments. Under LCO2 they were maintained for almost all of the 28 days of the acclimatization period, while becoming scarcely detected after 14 days under HCO2 and after 7 days when HCO2 was associated with HL. These results appear to confirm the counteraction of HCO2 concentrations over the oxidative stress eventually caused by HL. The patterns of soluble sugars in acclimatizing leaves under HLHCO2 also gave an indication of a faster acquisition of autotrophic characteristics.

母株から採取したシュートの接ぎ木によるピーマン（Ｃａｐｓｉｃｕｍ ａｎｎｕｕｍ Ｌ．）の苗生産方法‐接ぎ木活着率・苗質に及ぼす養生条件の影響

The effects of recuperating condition of grafting of sweet pepper scions harvested from a common mother plant were investigated. When mature sweet pepper shoots were grafted onto rootstocks of different cultivars, the success rate was about 75%. However, quite a few leaves fell from almost all grafts during three weeks of recuperation and acclimatization treatment. Growth was repressed on grafts in which three or more leaves fell and their fruit yields were rather low. In contrast, growth and yields of the grafts in which one or two leaves fell were equal to control seedlings; these were designated as good transplants. Examination of exposing stock/sion combinations to 15°C to 25°C for 4 to 7 days on percentage take revealed that the union healed fastest at 22.5°C; it was slower at lower temperatures. The higher the temperature, the more leaves fell. Transplant yield was highest (92%) when the temperature was maintained at 15°C for first four days and then raised stepwise daily to 17.5°C, 20°C, and 25°C on the seventh day. The grafts were transferred for acclimatization. The percentage take of grafts and yield of good transplants differed among cultivars used for rootstock, but a wide variety of sweet peppers served as good rootstocks.

Mass Propagation of Eucalyptus camaldulensis in a Scaled-up Vessel Under In Vitro Photoautotrophic Condition

A scaled-up culture vessel was designed for the large-scale photoautotrophic micropropagation of chlorophyllous plants. The culture vessel (volume 20l) contained a plug cell tray with 448 plantlets, and had a forced ventilation system to supply CO2-enriched air. A nutrient-reservoir was connected to the culture vessel from which nutrient solution was circulated to the culture vessel every 24h. Nodal leafy cuttings of Eucalyptus camaldulensis L. were cultured photoautotrophically in this system without sugar in the nutrient medium, but with an enriched CO2concentration and a high photosynthetic photon flux. The growth and the net photosynthetic rate of the in vitro grown plantlets and the survival percentage of the plantlets after transplanting to ex vitro conditions were compared with those of plantlets grown photoautotrophically under natural ventilation in conventional small culture vessels (Magenta-type vessels; volume 0.4l). Fresh and dry masses and net photosynthetic rate were significantly higher in plantlets grown in the scaled-up vessel compared to plantlets grown in the conventional small vessels (control). The environmental conditions created in this scaled-up vessel (with forced ventilation) also facilitated acclimatizationin vitro . Importantly, after transplanting to the ex vitro condition, plantlets grew well without any specializedex vitro acclimatization treatment.

In vitro hardening of red raspberry through CO2 enrichment and relative humidity reduction on sugar-free medium

Micropropagated shoots of red raspberry (Rubus idaeus L. ’Comet’) were rooted on modified Murashige-Skoog medium lacking sucrose, in specially constructed plexiglass chambers, under ambient (340 ± 20 ppm) or enriched (1500 ± 50 ppm) CO2 and ambient (ca. 100%) or reduced (90 ± 5%) relative humidity. Cultured plantlets were evaluated for their survival, rooting and relative vigor, leaf and root number, stem and root length, total leaf area, total fresh and dry weight, gas exchange rate, and stomatal features, prior to transplantation to soil and at intervals for 6 wk ex vitro. In vitro CO2 enrichment promoted plantlet growth, rooting and both the survival and early growth of transplants. CO2 enrichment increased stomatal aperture of plantlet leaves but did not apparently increase water stress at transplantation. Reduced in vitro RH did not affect plantlet growth but decreased stomatal apertures and stomatal index on leaves of cultured plantlets and promoted both the survival and early growth of transplants. In vitro CO2 and RH levels did not affect the photosynthetic rate of either plantlets or transplants. Only the stomata on leaves of plantlets from the ambient CO2 and reduced RH treatment were functional. Normal stomatal function was not observed in persistent leaves of transplants from the other treatments, even 2 wk after transplantation. In vitro CO2 enrichment acted synergistically with RH reduction in improving growth of plantlets both in vitro and ex vitro. Hardened red raspberry plantlets obtained through CO2 enrichment and RH reduction survived direct transfer to ambient greenhouse conditions without the necessity for specialized ex vitro acclimatization treatment. Key words: Acclimatization, growth analysis, photosynthesis, Rubus idaeus L., stomata, tissue culture

Cold tolerance of the pupae in relation to the distribution of swallowtail butterflies

A steep decline in the diversity of swallowtail butterfly species at high latitudes could be due to limited cold tolerance of overwintering pupae. If this is so, species with unusually northerly distributions should be unusually cold tolerant. We compared the northerly distributed Papilio canadensis with its southern relative, P. glaucus. Pupae were exposed for 2–5 months to four acclimatization treatments: outdoors in Alaska, outdoors in Michigan, constant 5 °C, and constant −25 °C. Field temperatures encountered by pupae in Alaska were lower than in Michigan. The supercooling point of P. glaucus pupae was unaffected by acclimatization (mean ± SE= −23.5 ± 0.52 °C). The supercooling point of P. canadensis pupae did not differ from that of P. glaucus pupae, except following acclimatization in Alaska, when it dropped to −27.0 ± 0.55 °C. Survival of pupae in Michigan was high for all populations (70–90%); in Alaska, survival of P. canadensis was just as high, but survival of P. glaucus dropped to 14%. Freezing was usually fatal in both species, but death was not immediate. No pupae survived 6 weeks at −25 °C. Trehalose was the most conspicuous metabolite revealed by nuclear magnetic resonance spectroscopy of live pupae and hemolymph. Labelled glucose was metabolized differently by the two species, which may underly the difference in acclimation potential and cold tolerance. The results support the hypothesis that winter temperatures limit swallowtail distributions.

The influence of acclimatization treatment and plantlet morphology on early greenhouse-performance of tissue-cultured Douglas fir [Pseudotsuga menziesii (Mirb.) Franco

The objective of this investigation was to test for the possible effects of plantlet morphology and environmental stress on survival and growth during the acclimatization of tissue-cultured Douglas fir [Pseudotsuga menziesii (Mirb.) Franco]. Under a high-stress environmental regime of 40–70% relative humidity and 22–28°C, survival was 33%, compared to 89% under a low-stress regime of 80–90% RH and 15–20°C. Shoot elongation under low stress was twice as great as that under high stress. Certain morphological features were associated with improved survival under high stress, and they included a large (10+) root number, tall (40 + mm) shoots, and upright needles. Plantlets with 10 + roots had 52% survival, compared to 25% or 31% for those with 1–3 or 4–10 roots, respectively. Also, plantlets with an initial shoot height of 41–60 mm had a 53% survival rate compared to 20% or 37% for those with 21–30 mm or 31–40 mm shoots. Tall plantlets and those with 10+ roots also underwent the greatest shoot elongation during the 7 week observation period. However, plagiotropism was frequent on tall shoots.

THE ACCLIMATIZATION OF PLANTS TO CHILLING TEMPERATURES IN RELATION TO THE FATTY‐ACID COMPOSITION OF LEAF POLAR LIPIDS

SummaryAn examination was made of the effects of low‐temperature acclimatization on the fatty‐acid composition of the polar lipids of two chill‐sensitive species Gossypium hirsutum and Phaseolus vulgaris which harden readily against chilling injury. As controls, the effect of hardening temperatures on a chill‐resistant species, Hordeum vulgare, and a chill‐sensitive species, Episcia reptans, which did not harden were also investigated. The degree of unsaturation of the fatty acids associated with the phospholipid fraction increased during hardening of Gossypium hirsutum and Phaseolus vulgaris. Furthermore, the degree of unsaturation and weight of phospholipids decreased in the leaves of these species with increase in physiological age at 25° C and was related to the increased susceptibility of older leaves to chilling injury. The acclimatization treatment produced no effects on the fatty‐acid composition of the glycolipids of these plants and this agreed with earlier observations which showed no increase in unsaturation of the total leaf fatty acid on hardening (Wilson and Crawford, 1974). Therefore, in leaves, it was the phospholipid fraction alone and representing only 22% of the total leaf fatty acids that had its degree of unsaturation positively related to the chilling tolerance of the species investigated. These findings are discussed in relation to similar ones made on the acclimatization of animals to low temperatures.