scholarly journals A Heat Unit Accumulation Method for Predicting Cucumber Harvest Date

1996 ◽  
Vol 6 (1) ◽  
pp. 27-30 ◽  
Author(s):  
Katharine B. Perry ◽  
Todd C. Wehner
Keyword(s):  
North Carolina ◽  
Production Systems ◽  
Planting Date ◽  
Harvest Date ◽  
Daily Maximum ◽  
Base Temperature ◽  
Harvest Dates ◽  
The Difference ◽  
Maximum Temperatures ◽  
Accumulation Method

The use of a previously developed model for predicting harvest date in cucumber production systems is described. In previous research we developed a new method using daily maximum temperatures in heat units to predict cucumber harvest dates. This method sums, from planting to harvest, the daily maximum minus a base temperature of 60F (15.5 C), but if the maximum is >90F (32C) it is replaced by 90F minus the difference between the maximum and 90F. This method was more accurate than counting days to harvest in predicting cucumber harvest in North Carolina, even when harvest was predicted using 5 years of experience for a particular location and planting date.

scholarly journals Influence of Planting Date, Fungicide Seed Treatment, and Phorate on Peanut in North Carolina

2019 ◽  
Vol 46 (1) ◽  
pp. 14-21
Author(s):  
D.J. Mahoney ◽  
D.L. Jordan ◽  
R.L. Brandenburg ◽  
B.B. Shew ◽  
B.R. Royals ◽  
...  
Keyword(s):  
North Carolina ◽  
Seed Treatment ◽  
Production Systems ◽  
Negative Impact ◽  
Planting Date ◽  
Soil Borne Pathogens ◽  
Arachis Hypogaea L ◽  
Treated Seed ◽  
Tobacco Thrips ◽  
Negative Impacts

ABSTRACT Establishing an adequate stand of peanut (Arachis hypogaea L.) and minimizing the negative impact of tobacco thrips [Frankliniella fusca (Hinds)] is important for maximizing yield in both organic and conventional production systems. The incidence, severity, and impact of soil borne pathogens and thrips populations on peanut may be influenced by planting date, fungicide seed treatment, and/or systemic insecticide application. However, the interaction of these management techniques has not been investigated in North Carolina with Virginia market type cultivars to date. As such, research was conducted over four years in North Carolina to determine peanut stand, injury caused by tobacco thrips feeding, and pod yield as influenced by planting date (early, mid-, and late-May), fungicide seed treatment, and phorate applied in the seed furrow at planting. Peanut stand increased when planting fungicide-treated seed compared to non-treated seed, although the magnitude of this effect lessened with later May plantings. Regardless of phorate treatment, less thrips injury was noted when peanut was planted in mid- or late-May compared with early May in three of four years. Yet the addition of phorate in-furrow further reduced thrips injury at every planting date. Peanut yield increased 75% and 50% of the time when seed was treated with fungicide and phorate was applied in the seed furrow at planting, respectively. Yield was generally greater when peanut was planted in mid-May and late-May compared to planting in early May irrespective of fungicide seed treatment or phorate treatment. Peanut stand was negatively and positively correlated with observed thrips injury and peanut yield, respectively. Additionally, peanut yield was negatively correlated to thrips injury. These data suggest that conventional producers should utilize treated seed and phorate in-furrow for thrips management regardless of planting date and that organic producers should plant in late May to minimize negative impacts of thrips and soil borne pathogens.

scholarly journals Plant Hardiness Zone Map in Korea and an Analysis of the Distribution of Evergreen Trees in Zone 7b

2021 ◽  
Vol 24 (5) ◽  
pp. 519-527
Author(s):  
Jung Nam Suh ◽  
Yun-Im Kang ◽  
Youn Jung Choi ◽  
Kyung Hye Seo ◽  
Yong Hyun Kim
Keyword(s):  
Global Warming ◽  
Temperature Fluctuation ◽  
Daily Maximum ◽  
Meteorological Observation ◽  
Before And After ◽  
Extreme Minimum Temperature ◽  
Data Portal ◽  
The Difference ◽  
Maximum Temperatures ◽  
Plant Hardiness

Background and objective: This study was conducted to establish a Plant Hardiness Zone (PHZ) map, investigate the effect of global warming on changes in PHZ, and elucidate the difference in the distribution of evergreen trees between the central and southern region within hardiness Zone 7b in Korea. Methods: Mean annual extreme minimum temperature (EMT) and related temperature fluctuation data for 40 years (1981 to 2020) in each of the meteorological observation points were extracted from the Open MET Data Portal of the Korea Meteorological Administration. Using EMT data from 60 meteorological observation points, PHZs were classified according to temperature range in the USDA Plant Hardiness Zone Map. Changes in PHZs for each decade related to the effects of global warming were analyzed. Temperature fluctuation before and after the day of EMT were analyzed for 4 areas of Seoul, Suwon, Suncheon, and Jinju falling under Zone 7b. For statistical analysis, descriptive statistics and ANOVA were performed using the IBM SPSS 22 Statistics software package. Results: Plant hardiness zones in Korea ranged from 6a to 9b. Over four decades, changes to warmer PHZ occurred in 10 areas, especially in colder ones. Based on the analysis of daily temperature fluctuation, the duration of sub-zero temperatures was at least 2 days in Seoul and Suwon, while daily maximum temperatures were above zero in Suncheon and Jinju before and after EMT day. Conclusion: It was found that the duration of sub-zero temperatures in a given area is an important factor affecting the distribution of evergreen trees in PHZ 7b.

scholarly journals Effect of Planting Date and Cultivar Maturity in Edamame Quality and Harvest Window

2021 ◽  
Vol 11 ◽  
Author(s):  
David Moseley ◽  
Marcos Paulo da Silva ◽  
Leandro Mozzoni ◽  
Moldir Orazaly ◽  
Liliana Florez-Palacios ◽  
...  
Keyword(s):  
The United States ◽  
Planting Date ◽  
Harvest Date ◽  
Timely Manner ◽  
Phenological Stages ◽  
Planting Dates ◽  
Harvest Dates ◽  
Key Factor ◽  
Harvest Strategy ◽  
The Impact

Edamame is a food-grade soybean [Glycine max (L.) Merr.] that is harvested immature between the R6 and R7 reproductive stages. To be labeled as a premium product, the edamame market demands large pod size and intense green color. A staggered harvest season is critical for the commercial industry to post-harvest process the crop in a timely manner. Currently, there is little information to assist in predicting the optimum time to harvest edamame when the pods are at their collective largest size and greenest color. The objectives of this study were to assess the impact of cultivar, planting date, and harvest date on edamame color, pod weight, and a newly minted Edamame Harvest Quality Index combining both aforementioned factors. And to predict edamame harvest quality based on phenological stages, thermal units, and planting dates. We observed that pod color and weight depended on the cultivar, planting date, and harvest date combination. Our results also indicated that edamame quality is increased with delayed planting dates and that quality was dependent on harvest date with a quadratic negative response to delaying harvest. Maximum quality depended on cultivar and planting and harvest dates, but it remained stable for an interval of 18–27 days around the peak. Finally, we observed that the number of days between R1 and harvest was consistently identified as a key factor driving edamame quality by both stepwise regression and neural network analysis. These research results will help define a planting and harvest strategy for edamame production in Arkansas and the United States Mid-South.

MODIFICATION OF THE HEAT UNIT FORMULA FOR PEAS

1962 ◽  
Vol 42 (1) ◽  
pp. 15-21 ◽  
Author(s):  
G. W. Hope
Keyword(s):  
Daily Maximum ◽  
Base Temperature ◽  
Heat Unit ◽  
Yearly Variation ◽  
Coefficients Of Variation ◽  
Maximum Temperatures ◽  
Unit Formula

The yearly variation in computed heat unit requirements of Perfection peas was reduced by modifying the method of deriving the units. Coefficients of variation of heat unit sums derived from daily means were lowest when daily maximum temperatures in excess of 60°F. were equated to 60° and when a base temperature of 36°F. was subtracted from the mean.Heat unit sums obtained from daily maxima were as homogeneous as those obtained from daily means.

scholarly journals Seed Germination and Early Growth Responses of Hyssop, Sweet Basil and Oregano to Temperature Levels

2013 ◽  
Vol 5 (4) ◽  
pp. 462-467 ◽  
Author(s):  
Sajad MIJANI ◽  
Samieh ESKANDARI NASRABADI ◽  
Hadi ZARGHANI ◽  
Mohhamad GHIAS ABADI
Keyword(s):  
Germination Rate ◽  
Germination Percentage ◽  
Effect Of Temperature ◽  
Base Temperature ◽  
Growth Responses ◽  
Model Base ◽  
Sweet Basil ◽  
The Difference ◽  
Maximum Temperatures ◽  
Temperature Levels

The objectives of this survey were to determine the effect of temperature on germination and seedling growth of Hyssop (Hyssopus officinalis L.), Sweet basil (Ocimum basilicum L.) and Oregano (Origanum vulgare L.) (Lamiaceae family) as well as comparing species regarding germination behavior and growth characteristics. Seeds were germinated on a temperature-gradient bar varying between 5 and 40 °C (with 5 °C intervals). Results indicated that the highest germination percentage of hyssop (92-98%), sweet basil (86-90%) and oregano (74-77%) occurred at 20-30 °C, 25-30 °C and 20-30 °C, respectively; therefore, moderate and warm temperatures are proper for germination of all species. In all species the maximum germination rate obtained at 30 °C. Among all species, Day 10 % of Sweet basil Germination had the lowest value, which indicates faster germination. The cardinal temperatures (base, optimum and ceiling or maximum) were estimated by the segmented model. Base temperature (Tb) was calculated for hyssop, sweet basil and oregano as 3.42, 5.70 and 5.46 °C, respectively. Optimal temperature (To) calculated for all species was approximately 30°C, So warmer temperatures are much more proper for them. The species showed different maximum temperatures (Tm) from 42.91 (Oregano) to 48.05 °C (Hyssop). In Hyssop and Sweet basil optimum growth of seedlings were observed at 30°C while Oregano reached its best growth at 25°C. The difference between maximum and minimum temperatures of germination knowing as temperature range (TR) index could show adaptation capability to broad sites for planting and domestication. Regarding this index Hyssop stood in the first place.

scholarly journals Predicting white spruce cone crops in the boreal forests of southern and central Yukon

2017 ◽  
Vol 47 (1) ◽  
pp. 47-52 ◽  
Author(s):  
C.J. Krebs ◽  
M. O’Donoghue ◽  
Shawn Taylor ◽  
A.J. Kenney ◽  
E.J. Hofer ◽  
...  
Keyword(s):  
Picea Glauca ◽  
Boreal Forests ◽  
Predictive Performance ◽  
Information Criterion ◽  
White Spruce ◽  
Daily Maximum ◽  
Degree Days ◽  
The Difference ◽  
Maximum Temperatures ◽  
Regional Synchrony

White spruce (Picea glauca (Moench) Voss) cone crops were measured at five regional centers in southern and central Yukon for 30 years at one site from 1986 to 2015 and at four other sites during 9 to 11 years to select the best climatic model that uses cues from growing season temperature and rainfall to predict the size of cone crops. We evaluated six climatic models that use summer temperature and rainfall of years t – 1 and t – 2 to predict cone crops in year t. July temperatures provided the best predictors of white spruce cone crops, and no rainfall variable was related to the size of cone crops. We explored three variants of July temperatures: mean temperature, degree-days > 5 °C, and maximum temperatures. For each of these, we used the ΔT model that uses the difference in the July temperature measures of years t – 1 and t – 2. We compared the resulting six models with corrected Akaike’s information criterion (AICc) to determine their relative predictive performance. The best model combined ΔT measures of degree-days > 5 °C and the four highest daily maximum July temperatures with R2 = 0.65. By comparison, the ΔT model involving only mean July temperatures was less successful (R2 = 0.49). There was good regional synchrony (rp = 0.7 to 0.8) in high cone crops over southern and central Yukon during 1986 to 2015.

scholarly journals Predicting Yield and Time to Maturity of Muskmelons from Weather and Crop Observations

1998 ◽  
Vol 123 (2) ◽  
pp. 195-201 ◽  
Author(s):  
Sylvie Jenni ◽  
Katrine A. Stewart ◽  
Gaétan Bourgeois ◽  
Daniel C. Cloutier
Keyword(s):  
Total Yield ◽  
Developmental Time ◽  
Daily Maximum ◽  
Base Temperature ◽  
Heat Unit ◽  
Data Set ◽  
Simple Method ◽  
Fruit Maturity ◽  
Richards Function ◽  
Maximum Temperatures

A simple method to predict time from anthesis of perfect flowers to fruit maturity (full slip) and yield is presented here for muskmelon (Cucumis melo L.) grown in a northern climate. Developmental time for individual muskmelons from anthesis to full slip could be predicted from several heat unit formulas, depending on the temperature data set used. When temperature at 7.5 cm above soil level was used, the heat unit formula resulting in the lowest coefficient of variation (cv=6.9%) accumulated daily average temperatures with a base temperature of 11 °C and an upper threshold of 25 °C. With temperatures recorded at a meteorological station located 2 km from the experimental field, the method showing the lowest cv (8.9%) accumulated daily maximum temperatures with a base temperature of 15 °C. This latter method was improved by including a 60-degree-day lag for second cycle fruit. The proportion of fruit volume at full slip of 22 fruit from the first cycle could be described by a common Richards function (R2=0.99). Although 65% of the plants produced two fruit cycles, fruit from the first cycle represented 72% of total yield in terms of number and mass. The blooming period of productive flowers lasted 34 days, each cycle overlapping and covering an equal period of 19 days. Counting the number of developing fruit >4 cm after 225 degree days from the start of anthesis (when 90% of the plants have at least one blooming perfect flower) could rapidly estimate the number of fruit that will reach maturity.

scholarly journals Connection of fertilization conditions of sour cherry and meteorological parameters

2010 ◽  
Vol 16 (1) ◽  
Author(s):  
L. Lakatos ◽  
T. Szabó ◽  
M. Soltész ◽  
Z. Szabó ◽  
M. C. Dussi ◽  
...  
Keyword(s):  
Minimum Temperature ◽  
Sunshine Duration ◽  
Sour Cherry ◽  
Maximum Temperature ◽  
Daily Maximum ◽  
Low Degree ◽  
Development Duration ◽  
Self Fertilization ◽  
The Difference ◽  
Maximum Temperatures

Our analyses showed that the degree of free fertilization is mostly influenced by maximum temperature and sunshine duration.We found that free fertilization ratio increases with higher daily maximum temperatures; similar results characterise sunshine duration as well, namely we observed higher free fertilization ratio at higher sunshine duration values. Total amount of precipitation during the period between blossoming and maturity and the difference between the average daytime and night temperatures have an important role in the tendency of maturity time. Photosynthesis and respiration are essentially significant in the development of biological systems. These two processes are mostly regulated by the daytime and night temperatures. Therefore, it is not surprising that if the difference between daytime and night temperatures is large, it means intensive photosynthesis and a low degree of respiratory loss. Under these conditions intensive development and ripening can take place; however, in case of a low temperature difference intensive respiration slows down the process of development. Duration of ripening is also significantly influenced by the amount of precipitation of the period between blossoming and maturity.Abundant precipitation slows down the process of ripening, while dry weather accelerates it. Self-fertilization takes place in a space isolated from the environment. In spite of that, we found that effectiveness of self-pollination significantly depends on the meteorological conditions. Degree of self-fertilization is influenced directly by temperature and indirectly by other climatic parameters. We found a significant connection between the values of maximum and minimum temperatures during blossoming and the ratio of self-fertilization. Increase of maximum temperature reduces the effectiveness of self-pollination.A 1 °C increase of maximum temperature reduces self-fertilization ratio by 0,6%. In the case of minimum temperature we can state that the morning minimum temperature of 7,5–8,5°C is the most favourable. If minimum temperatures are under 4 °C or above 12 °C, self-fertilization ratio reduces to the quarter of the value characteristic at 8 °C. We believe that the effectiveness of self-fertilization can be improved considerably by the rational placement of isolator bags within the crown area, avoiding their placement to the external, western crown surface.

Using Land Cover, Population, and Night Light Data for Assessing Local Temperature Differences in Mainz, Germany

2015 ◽  
Vol 54 (3) ◽  
pp. 658-670 ◽  
Author(s):  
Jenny Lindén ◽  
Jan Esper ◽  
Björn Holmer
Keyword(s):  
Twentieth Century ◽  
Light Intensity ◽  
Central Europe ◽  
Urban Growth ◽  
Urban Areas ◽  
Surface Coverage ◽  
Daily Maximum ◽  
Source Areas ◽  
Maximum Temperatures ◽  
The City

AbstractUrban areas are believed to affect temperature readings, thereby biasing the estimation of twentieth-century warming at regional to global scales. The precise effect of changes in the surroundings of meteorological stations, particularly gradual changes due to urban growth, is difficult to determine. In this paper, data from 10 temperature stations within 15 km of the city of Mainz (Germany) over a period of 842 days are examined to assess the connection between temperature and the properties of the station surroundings, considering (i) built/paved area surface coverage, (ii) population, and (iii) night light intensity. These properties were examined in circles with increasing radii from the stations to identify the most influential source areas. Daily maximum temperatures Tmax, as well as daily average temperatures, are shown to be significantly influenced by elevation and were adjusted before the analysis of anthropogenic surroundings, whereas daily minimum temperatures Tmin were not. Significant correlations (p < 0.1) between temperature and all examined properties of station surroundings up to 1000 m are found, but the effects are diminished at larger distance. Other factors, such as slope and topographic position (e.g., hollows), were important, especially to Tmin. Therefore, properties of station surroundings up to 1000 m from the stations are most suitable for the assessment of potential urban influence on Tmax and Tmin in the temperate zone of central Europe.

scholarly journals GIS-Based Energy Consumption and Spatial Variation of Protected Grape Cultivation in China

2018 ◽  
Vol 10 (9) ◽  
pp. 3248 ◽  
Author(s):  
Dong Tian ◽  
Min Zhang ◽  
Xuejian Wei ◽  
Jing Wang ◽  
Weisong Mu ◽  
...  
Keyword(s):  
Renewable Energy ◽  
Energy Consumption ◽  
Total Energy ◽  
Energy Input ◽  
Production Systems ◽  
Organic Fertilizer ◽  
Total Energy Consumption ◽  
Renewable Energy Consumption ◽  
Input Structure ◽  
The Difference

This paper compares the difference in energy consumption in different sub-patterns and features of energy consumption structures used in protected grape production systems using statistical data. Then, spatial characteristics between different production modes based on geographic information systems are also analyzed. The results reveal that the types of energy consumption include steel, iron wire, water, chemical fertilizer, pesticides, electric power, organic fertilizer, plastic films, and labor. The total energy consumption for protected grape production was 210,534.3 MJ ha−1 in 2011, 211,504.6 MJ ha−1 in 2012, and 222,571.8 MJ ha−1 in 2013. From the perspective of cultivation modes, early ripening production and late ripening production consumed more energy than rain-shelter production; in terms of facility types, the total energy input of both vinyl tunnels and solar greenhouses were always higher than rain-shelter greenhouses. Indirect and non-renewable energy consumption were higher than that of direct and renewable energy, which accounted for 90% of energy consumption. Spatial analysis showed that the values of Moran’s I were all positive for the three years, which means protected grape input had a positive spatial autocorrelation. Therefore, we should adjust the energy input structure and choose more sustainable production modes to improve the sustainability of the production of protected grapes.

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