Estimation of seasonal ascospore production of Mycosphaerellapopulorum

1991 ◽  
Vol 21 (9) ◽  
pp. 1349-1353 ◽  
Author(s):  
Christopher J. Luley ◽  
Harold S. McNabb Jr.
Keyword(s):  
Laboratory Data ◽  
Growing Season ◽  
Regression Coefficients ◽  
Degree Days ◽  
Degree Day ◽  
Collection Data ◽  
Moist Environment ◽  
The Difference ◽  
Ascospore Production ◽  
Coated Slide

A model was developed that estimates ascospore production by Mycosphaerellapopulorum Thompson in response to degree-days. Spore production and release in two field seasons were monitored with an ascospore liberation tunnel and Vaseline-coated slide traps, respectively. Ascospore production in a moist environment and under controlled temperatures was monitored in the laboratory with the liberation tunnel. Ascospores were produced in the laboratory for periods of 192, 98, and 74 days at 9, 16, and 21 °C, respectively, after initial ascospore maturation. Field and laboratory ascospore collection data were linearized with a Gompit transformation. Regression coefficients on the linearized data were greatest when a degree-day base of 0 °C was used. Slopes of the regression lines (k-values) developed from laboratory and field (1984 season) data were not significantly different. The k-values from laboratory data and data collected during the 1985 growing season were significantly different. The difference was attributed to dry weather during the period of ascospore production and release. The laboratory regression model could be used to predict ascospore production during the growing season after initial ascospore maturation if adequate moisture is present and if degree-day accumulation is predicted.

scholarly journals Determining Heat Unit Requirements for Broccoli Harvest in Coastal South Carolina

1997 ◽  
Vol 122 (2) ◽  
pp. 169-174 ◽  
Author(s):  
Robert J. Dufault
Keyword(s):  
South Carolina ◽  
Standard Method ◽  
Growing Season ◽  
Base Temperature ◽  
Degree Days ◽  
Heat Unit ◽  
Mean Temperature ◽  
Coefficients Of Variation ◽  
The Mean ◽  
The Difference

The objective of this research was to determine the least variable method to predict the dates of the first and last broccoli (Brassica oleracea L. var Italica) harvests based on heat unit summation using coefficients of variation (cv). The method with the lowest cv for predicting first harvest was to sum, over days from planting to harvest, the difference between the growing season mean (GSM) temperature and a base temperature of 7.2 °C. If the GSM maximum (max) temperature, however, was >26.7 °C, an adjusted max temperature was calculated by first subtracting 26.7 °C from the GSM max temperature and then subtracting the GSM mean temperature. Then the growing degree days (GDDs) were summed by subtracting the base temperature of 7.2 °C from the average of the GSM minimum (min) and adjusted max temperatures. This method produced a cv of 3.96 compared to 4.13 for the standard method of summing over the entire growing season, the mean temperature minus the base temperature of 4.4 °C. The method with the lowest cv for predicting last harvest was to sum, over days from planting to harvest, the difference between the GSM max temperature and a base temperature of 7.2 °C. If the GSM max temperature, however, was >29.4 °C, the base temperature was subtracted from 29.4 °C and not the actual GSM max temperature. This method produced a cv of 3.71 compared to 4.10 for the standard method of summing over the growing season, the mean temperature minus the base of 4.4 °C.

scholarly journals What is the Uncertainty in Degree-Day Projections due to Different Calibration Methodologies?

2017 ◽  
Vol 30 (22) ◽  
pp. 9059-9075 ◽  
Author(s):  
Caroline Holmes ◽  
Simon Tett ◽  
Adam Butler
Keyword(s):  
Energy Use ◽  
Climate Model ◽  
Absolute Number ◽  
Degree Days ◽  
Temperature Index ◽  
Degree Day ◽  
Heating And Cooling ◽  
Cooling Degree Days ◽  
The Difference ◽  
The Impact

Degree-days are a temperature index used for understanding the impact of climate change. Different methods to deal with climate model biases, termed bias correction or more generally calibration, yield different projections of such indices, something not widely understood for temperature indices in many impact sectors. An analytical expression is derived for the expected value of degree-days given parameters of the underlying statistical distribution (assumed to be Gaussian). It is demonstrated that the uncertainty introduced by calibration methodology is driven by the magnitude of the nonlinearity in this expression. In a climate where mean temperature is, and remains, far from (approximately three standard deviations) the threshold used in defining the index, the equation is approximately linear, and methodological choice makes little difference relative to the absolute number of degree-days. However, case studies for U.K. cities London and Glasgow for heating and cooling degree-days (HDD and CDD; these are degree-day indices used in the estimation of energy use for heating and cooling buildings) demonstrate that, when temperatures are close to the threshold, unrealistic results may arise if appropriate calibration is not performed. Seasonally varying temperature biases in the 11-member perturbed parameter ensemble HadRM3 are discussed, and different calibration strategies are applied to this ensemble. For projections of U.K. HDD, the difference between results from simple and advanced methodologies is relatively small, as the expression for HDD is approximately linear in many months and locations. For U.K. CDD, an inappropriate method has a large relative impact on projections because of the proximity to the threshold. In both cases, the uncertainty caused by methodology is comparable to that caused by ensemble spread.

Applications of the herbicide sethoxydim increase wheat yield in the absence of weeds

1996 ◽  
Vol 36 (5) ◽  
pp. 555
Author(s):  
ID Black ◽  
CB Dyson ◽  
AR Fischle
Keyword(s):  
Leaf Growth ◽  
Wheat Yield ◽  
South Australia ◽  
Growing Season ◽  
Degree Days ◽  
Experimental Site ◽  
Yield Increase ◽  
Growing Seasons ◽  
Positive Linear Correlation ◽  
Area North

In 11 experiments over 6 seasons the herbicide sethoxydim was applied to Machete, Spear and Blade wheat cultivars in the absence or near absence of weeds (10 sites) or where the weeds were controlled by selective herbicides (1 site), in the cropping area north of Adelaide, South Australia. The rates applied included 9-47 g a.i./ha at the 2-3 leaf growth stage and 9-74 g a.i./ha at early tillering. Except for the very long growing season of 1992, there was a highly significant positive linear correlation between the number of degree days in the growing season at each experimental site and relative mean yield increase of these sethoxydim treatments. Yield increases ranged from nil in growing seasons of about 1000 degree days to 32% in a growing season of 1480 degree days, with a median of 8% over the experiments.

scholarly journals Effects of Environmental Temperature onCapnodis tenebrionisAdult Phenology

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Carmelo Peter Bonsignore
Keyword(s):  
Late Summer ◽  
Early Summer ◽  
Adult Density ◽  
Degree Days ◽  
Continuous Increase ◽  
Climate Conditions ◽  
Average Annual Temperature ◽  
Activity Temperature ◽  
The Difference ◽  
New Generation

The phenology ofCapnodis tenebrionisadults was presented with reference to two different climate conditions. In a temperate moderate-warm climate, adult density showed two separate peaks during the year: one in early summer of the overwintering generation and one with beetles emerging in the late summer. In a warmer semiarid climate, the overwintering adults and the new generation overlapped during summer with a continuous increase of adult density. The difference in the average annual temperature between areas during the study period was almost3∘C, and, in the warmer area, the new generation ofC. tenebrionisemerged at least one month earlier. To make a prediction of adult presence, a model utilizing degree-days was developed from data collected over a five-year period. Models obtained from equations (Logistic 4-parameter,y(x)=yo+a/(1+(x/xo)b)) of each year were developed to describe the relationship between degree-day accumulation (with a minimal threshold activity temperature of14.21∘Ccalculated in the laboratory) and the cumulative percentage of adult presence. According to the overall model, the 50% of overwintering beetles occurred at 726 degree-days (Biofix: 1st March) and the emerging beetles occurred at 801 degree-days (Biofix: 1st July). The results show that a change in temperature is an important aspect that highlights the adaptability of this species.

CHLOROGENIC ACID CONTENT OF SUNFLOWER SEED FLOUR AS AFFECTED BY SEEDING AND HARVEST DATE

1976 ◽  
Vol 56 (4) ◽  
pp. 901-905 ◽  
Author(s):  
D. G. DORRELL
Keyword(s):  
Chlorogenic Acid ◽  
Acid Content ◽  
Vegetative Growth ◽  
Sunflower Seed ◽  
Growing Season ◽  
Growing Degree Days ◽  
Degree Days ◽  
Normal Field ◽  
Seed Flour ◽  
Seeding Date

The effect of seeding date on the chlorogenic acid content of sunflower seed flour was determined by seeding the cultivars Krasnodarets and Peredovik at seven dates, starting on 14 May, over 3 yr. Sequential plantings were made at increments of approximately 70 growing degree days (base = 5.6 C). Plants were harvested at normal field maturity. The time and rate of deposition of chlorogenic acid was determined by harvesting plants at 7-day intervals from 21 to 49 days after flowering. The seeds were dehulled and defatted before determining the chlorogenic acid content of the flour. Chlorogenic acid content declined steadily from an average of 4.22% for the first seeding to 3.30% for the last seeding. About one-half of the total chlorogenic acid was present 21 days after flowering. Deposition continued rapidly for the next 14 days then the level began to stabilize. Delay in seeding tended to shorten the period of vegetative growth and shift the deposition of chlorogenic acid to a cooler portion of the growing season. It is suggested that a combination of these factors caused the reduction in chlorogenic acid content of sunflower flour.

Timing and rate of bud formation in Pinus resinosa

1971 ◽  
Vol 49 (10) ◽  
pp. 1821-1832 ◽  
Author(s):  
Edward Sucoff
Keyword(s):  
Quantitative Data ◽  
Shoot Growth ◽  
Pinus Resinosa ◽  
Growing Season ◽  
Axillary Buds ◽  
Growing Degree Days ◽  
Degree Days ◽  
Bud Formation ◽  
Late Season ◽  
Apical Dome

During the 1969 and 1970 growing season buds were collected almost weekly from matched trees in northeastern Minnesota. Cataphyll primordia for the year n + 1 shoot began forming at the time that internodes in the year n shoot started elongating (late April) and continued forming until early September. Primordia for axillary buds started forming about 2 months later and stopped forming at the same time as cataphylls. The size and deposition activity of the apical dome simultaneously increased during the early growing season and decreased during the late season. The maximum rates in July were over nine cataphylls per day.Rate of cataphyll deposition paralleled elongation of the needles on subtending shoots. Forty to fifty percent of the cataphylls had been formed when shoot growth was 95% complete. Although the bulk of the depositions occurred earlier in 1970, when growing degree days were used as the clock, the 2 years were similar.The results provide quantitative data to complement the histologic emphasis of previous studies.

scholarly journals Pengaruh Suhu terhadap Perkembangan Pradewasa Parasitoid Eriborus argenteopilosus Cameron (Hymenoptera: Ichneumonidae)

2012 ◽  
Vol 13 (3) ◽  
pp. 250
Author(s):  
Novri Nelly ◽  
Trimurti Habazar ◽  
Rahmat Syahni ◽  
Damayanti Buchori
Keyword(s):  
Survival Rate ◽  
Temperature Effect ◽  
Development Time ◽  
Degree Days ◽  
Degree Day ◽  
Adult Parasitoid ◽  
Different Temperatures ◽  
Lepidoptera Pyralidae

Temperature effect on development time of the preadult parasitoid Eriborus argenteopilosus Cameron(Hymenoptera: Ichneumonidae) were studied to know development time, degree days and survival rate.Crocidolomia pavonana (Fabricius)(Lepidoptera: Pyralidae) larvae was exposed to E. argenteopilosus female andreared at four different temperatures i.e 160C, 200C, 250C and 300C. Data were analyzed using anova and linearregression to calculate degree day. At 200C E. argenteopilosus showed the highest degree day and survival rate(18.67 %), while at 300C nothing adult parasitoid emergenced. Degree day to development time of parasitoid attemperature 200C i.e fase egg-adult: 300.05; egg-pupae 173.35; pupae-adult 171.

scholarly journals ECOLOGICAL-GEOGRAPHIC APPROACHES TO THE STUDY OF GENETIC DIVERSITY OF BARLEY AND OAT FROM THE VIR COLLECTION

2020 ◽  
Author(s):  
Igor Loskutov ◽  
Lubov Novikova ◽  
Olga Kovaleva ◽  
Nadezhda Ivanova ◽  
Elena Blinova ◽  
...  
Keyword(s):  
Environmental Conditions ◽  
Growing Season ◽  
Regression Coefficients ◽  
Cultivation Conditions ◽  
High Productivity ◽  
Sum Of Effective Temperatures ◽  
Economically Valuable Traits ◽  
Effective Temperatures ◽  
The Stability ◽  
Selection Of

Under conditions of climate change, the assessment of the stability of genotypes is of particular importance. To conduct directed selection of genotypes with a narrow or broad reaction rate, it is necessary to assess their stability already in the early stages of breeding. The aim of the study was to study the stability of breeding significant traits of oat and barley samples in contrasting ecological and geographical conditions. 25 oat samples and 25 barley samples were studied over 3 years under contrasting conditions in St. Petersburg and the Tambov region. Varieties are characterized by average values of economically valuable traits and genotype regression coefficients on the influence of the bi environment according to Eberhart and Russell. The most sensitive to a change in the ecological and geographical situation were the durations of the germination-heading, germination-harvest periods and grain yield. These characters varied to a greater extent depending on the cultivation conditions than on the genotype. According to regression coefficients for environmental conditions, significant differences in genotypes were only in yield. Contrasting groups of varieties were distinguished by regression coefficients on environmental conditions, genotypes with high productivity. The durations of germination-heading, germination-harvest, the plant height reacted to the change in the environment the same in different varieties. The duration of the growing season was determined by the sum of effective temperatures above 15C. The reduction of the growing season in both crops was 3 days with an increase in the sum of effective temperatures above 15C by 100C.

Spatial Analysis of Climate-Viticulture Indices for the Eastern United States

2016 ◽  
Vol 7 (4) ◽  
pp. 23-37 ◽  
Author(s):  
Rosalyn Francine MacCracken ◽  
Paul R. Houser
Keyword(s):  
United States ◽  
Spatial Analysis ◽  
Growing Season ◽  
Climate Indices ◽  
Growing Degree Days ◽  
Eastern United States ◽  
Degree Days ◽  
The Us ◽  
Resolution Dataset ◽  
Effective Degree

This study characterizes the climate structure in the Eastern United States for suitability of winegrape growth. For this study, the Eastern US is defined as the 44 contiguous Eastern most states. This excludes the premium wine growing states of California, Washington, Oregon and Idaho. For this characterization, a comparative study is performed on the four commonly used climate-viticulture indices (i.e., Average Growing Season Temperature, Growing Degree Days, Heliothermal Index and Biologically Effective Degree Days), and a new climate-viticulture index, the Modified-GSTavg (Mod-GSTavg). This is accomplished using the 1971 – 2000 PRISM 800-meter resolution dataset of climate temperature normal for the study area of 44 states and 62 American Viticultural Areas across the Eastern United States. The results revealed that all the climate indices have similar spatial patterns throughout the US with varying magnitudes and degrees of suitability.

scholarly journals Forest Soil Respirations are More Sensitive to Nighttime Temperature Change in Eastern China

2018 ◽  
Vol 47 (1) ◽  
pp. 249-254
Author(s):  
Zhaoyong SHI ◽  
Ke LI ◽  
Yongming WANG ◽  
Bede S. MICKAN ◽  
Weikang YUAN ◽  
...  
Keyword(s):  
Soil Respiration ◽  
Soil Temperature ◽  
Temperature Change ◽  
Global Climate ◽  
Eastern China ◽  
Growing Season ◽  
Mean Value ◽  
Apparent Temperature ◽  
Effect Of Temperature ◽  
The Difference

Soil respiration is one of the main fluxes in the global carbon cycle. The effect of temperature on soil respiration is well understood. The response of soil respiration to temperature warming is called apparent temperature sensitivity (Q10) of soil respiration, which is an important parameter in modeling soil CO2 effluxes under global climate warming. The difference of Q10 between daytime and nighttime was hardly reported although attentions are attracted by the differences of temperature change and its effects on vegetation productivity. In this study, we investigated the Q10 of soil respiration in daytime and nighttime by modeling empirical functions based on the in situ measurement of soil respiration and temperature in temperate and subtropical forests of eastern China. Our results showed that the Q10 of soil respiration is higher in nighttime with the mean value of 2.74 and 2.35 than daytime with the average of 2.49 and 2.18 in all measured months and growing season, respectively. Moreover, the explanatory rate of soil temperature to soil respiration in nighttime is also higher than in daytime in each site in both all measured and growing seasons. The Q10 and explanatory rate of soil temperature to soil respiration in nighttime is 1.08 and 1.15 times in daytime in growing season. These findings indicate that soil respiration has a bigger sensitivity to temperature in nighttime than daytime. The change of soil temperature explains more variation of soil respiration in nighttime than daytime.

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