USING A GEOGRAPHIC INFORMATION SYSTEM (GIS) TO CHARACTERIZE AND TO MAP GROWING SEASONS FOR VEGETABLES

Vegetable production has become a multi-million dollar activity in Tennessee. The large number of options of planting dates and maturity classes of different vegetable species and cultivars result in a flexible, yet confusing, situation for the grower. A plentiful supply of vegetables for the processor, fresh market, or family table can be assured by the proper scheduling of planting and harvest of different crops and cultivars. Growers have very limited access to climatic data oriented to vegetable production in their locations. For the most part, they depend on planting maps on the backs of seed packets, or on extension bulletins with very general planting and harvest date recommendations. Tennessee consists of 4 climatic divisions that do not adequately describe the multitude of climates due to the diverse topography. The objective of this research was to create GIS maps of climatic variables important to vegetable production. Maps of temperatures, growing degree days, and rainfall, freeze and heat stress probabilities based on data from 72 locations in Tennessee were used to characterize the growing seasons for different vegetables.

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Improving the Prediction of Processing Pea Maturity Based on the Growing-degree Day Approach

HortScience ◽

10.21273/hortsci.35.4.611 ◽

2000 ◽

Vol 35 (4) ◽

pp. 611-614 ◽

Cited By ~ 4

Author(s):

Gaétan Bourgeois ◽

Sylvie Jenni ◽

Hélène Laurence ◽

Nicolas Tremblay

Keyword(s):

Current Model ◽

Climatic Conditions ◽

Developmental Period ◽

Temperature Data ◽

Growing Degree Days ◽

Base Temperature ◽

Degree Days ◽

Planting Dates ◽

Average Temperature ◽

Unit System

The heat-unit system, involving the sum of daily mean temperatures above a given base temperature, is used with processing pea (Pisum sativum L.) to predict relative maturity during the growing season and to schedule planting dates based on average temperature data. The Quebec pea processing industry uses a base temperature of 5 °C to compute growing-degree days (GDD) between sowing and maturity. This study was initiated to verify if the current model, which uses a base temperature of 5 °C, can be improved to predict maturity in Quebec. Four pea cultivars, `Bolero', `Rally', `Flair', and `Kriter', were grown between 1985 and 1997 on an experimental farm in Quebec. For all cultivars, when using a limited number of years, a base temperature between 0.0 and 0.8 °C reduced the coefficient of variation (cv) as compared with 5.0 °C, indicating that the base temperature used commercially is probably not the most appropriate for Quebec climatic conditions. The division of the developmental period into different stages (sowing until emergence, emergence until flowering, and flowering until maturity) was also investigated for some years. Use of base temperatures specific for each crop phase did not improve the prediction of maturity when compared with the use of an overall base temperature. All years for a given cultivar were then used to determine the base temperature with the lowest cv for predicting the time from sowing to maturity. A base temperature from 0 to 5 °C was generally adequate for all cultivars, and a common base temperature of 3.0 °C was selected for all cultivars. For the years and cultivars used in this study, the computation of GDD with a base temperature of 3 °C gave an overall prediction of maturity of 2.0, 2.4, 2.2, and 2.5 days based on the average of the absolute values of the differences for the cultivars Bolero, Rally, Flair, and Kriter, respectively.

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Use of Belowground Growing Degree Days to Predict Rooting of Dormant Hardwood Cuttings of Populus

Silvae Genetica ◽

10.1515/sg-2004-0028 ◽

2004 ◽

Vol 53 (1-6) ◽

pp. 154-160 ◽

Cited By ~ 10

Author(s):

R. S. Zalesny ◽

E. O. Bauer ◽

D. E. Riemenschneider

Keyword(s):

Populus Deltoides ◽

Dry Weight ◽

Growing Degree Days ◽

Base Temperature ◽

Degree Days ◽

Planting Dates ◽

Growing Period ◽

Period 2 ◽

Soil Temperatures ◽

Total Dry Weight

Abstract Planting Populus cuttings based on calendar days neglects soil temperature extremes and does not promote rooting based on specific genotypes. Our objectives were to: 1) test the biological efficacy of a thermal index based on belowground growing degree days (GDD) across the growing period, 2) test for interactions between belowground GDD and clones, and 3) identify beneficial planting windows based on combinations of genotypes and belowground GDD. We tested two clones of Populus deltoides Bartr. ex Marsh (D133, D134) and four hybrid clones of P. deltoides × P. maximowiczii A. Henry (DM101, DM105, NC14105, NC14107). Cuttings, 20 cm long, were planted in randomized complete blocks at 15- × 15-cm spacing across three planting dates during 1999 at Alexandria, Minnesota, USA (45.9°N, 95.4°W) and Fertile, Minnesota, USA (47.3°N, 96.2°W). Temperatures at 20 cm belowground were converted to GDD with a base temperature of 10°C. We measured root, top, and total dry weight, along with number of roots after 14 d of growth. Relatively warmer and cooler soil temperatures promoted rooting for the cottonwoods and hybrids, respectively. We recommend planting after reaching a threshold of 163 belowground GDD for P. deltoides clones and planting before reaching a threshold of 173 belowground GDD for P. deltoides × P. maximowiczii clones.

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Investigating morpho-physiological traits and agro-meteorological indices in green gram [Vigna radiata L. Wilczek] for terminal heat tolerance

Legume Research - An International Journal ◽

10.18805/lr.v0i0.7588 ◽

2016 ◽

Author(s):

Chandan Kumar ◽

S. B. Mishra ◽

Nilanjaya . ◽

Chandra Mohan Singh

Keyword(s):

Heat Stress ◽

Seed Yield ◽

Stress Condition ◽

Growing Degree Days ◽

Degree Days ◽

Relative Temperature ◽

Thermal Index ◽

Heat Stress Condition ◽

Use Efficiency ◽

Temperature Depression

Forty genotypes of greengram were studied to ascertain the genetic variability and trait association among some important morpho-physiological traits and agro-meterological indices under heat stress condition. The results indicated that both GCV and PCV estimates were high for photo thermal index, heat use efficiency and seed yield. High heritability coupled with moderate genetic advance as per cent of mean was recorded for photo-thermal unit and relative temperature depression indicated that involvement of both additive and non-additive type of gene action and possibilities of effective selection for improvement of these traits. Seed yield showed significant and positive association with days to maturity, growing degree days, relative temperature depression and heat use efficiency. Based on variability, association and path analysis; heat use efficiency, maturity, photo thermal index and growing degree days were found most contributing indices/ traits should be considered as selection criteria for discrimination of outstanding greengram genotypes under heat stress condition.

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The effect of planting date on the yield and some fibre properties of cotton in the Namoi Valley

Australian Journal of Experimental Agriculture ◽

10.1071/ea9760265 ◽

1976 ◽

Vol 16 (79) ◽

pp. 265 ◽

Cited By ~ 10

Author(s):

GA Constable ◽

NV Harris ◽

RE Paull

Keyword(s):

Adverse Effect ◽

Maximum Yield ◽

Planting Date ◽

Growing Degree Days ◽

Degree Days ◽

Planting Dates ◽

Fibre Properties ◽

Commercial Cultivar ◽

Yield Variation ◽

Early Maturing

The effect of planting dates between September 30 and November 30 on the yield and some fibre properties of two cotton cultivars has been studied over three seasons. The yield of the commercial cultivar (Deltapine Smoothleaf) fell by an average of 20 kg ha-1 day-1 delay in planting after October 20, earlier planting dates having equal yields, producing a plateau effect. The yield of an early maturing cultivar (Short Sympodial) fell linearly by 11 kg ha-1 day-1 delay in planting. Planting dates after mid-October had an adverse effect on micronaire in the commercial cultivar, but lint length and strength were not affected. Thus maximum yield and micronaire for plantings after mid-October came from the early cultivar. Tolerance to low temperature is an important factor in cultivar earliness, and accounts for the performance of Short Sympodial in these experiments. The number of days from first flower to first frost was as reliable as growing degree days in explaining yield variation within a cultivar

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When do apples stop growing, and why does it matter?

10.1101/2020.06.25.170910 ◽

2020 ◽

Cited By ~ 1

Author(s):

Maria D Christodoulou ◽

Alastair Culham

Keyword(s):

Linear Models ◽

Growing Season ◽

Apple Fruit ◽

Maximum Length ◽

Maximum Diameter ◽

Growing Degree Days ◽

Degree Days ◽

Growing Seasons ◽

Regular Time ◽

Log Linear

AbstractBackgroundApples in the commercial food chain are harvested up to two weeks before maturity. We explore apple fruit development through the growing season to establish the point at which the features differentiating those cultivars become evident. This is relevant both for the understanding of the growing process and to ensure that any identification and classification tools can be used both on ripened-on-tree and stored fruit. Current literature presents some contradictory findings on apple development, we explored the size development of 12 apple cultivars in the Brogdale National Fruit Collection, UK over two growing seasons.MethodsFruit were sampled at regular time points throughout the growing season and four morphometrics (maximum length, maximum diameter, weight, and centroid size) were collected. These were regressed against growing degree days in order to appropriately describe the growth pattern observed.ResultsAll four morphometrics were adequately described using log-log linear regressions, with adjusted R2 estimates ranging from 78.3% (maximum length) to 86.7% (weight). For all four morphometrics, a 10% increase in growing degree days was associated with a 1% increase in the morphometric measurement.DiscussionOur findings refine previous work presenting rapid early growth followed by a plateau in later stages of development and are in disagreement with published expo-linear models. We established that apples harvested for commercial storage purposes, two weeks prior to maturity, showed only a modest decrease in size, demonstrating that size morphometric approaches are appropriate for classification of apples, both ripened-on-tree and stored.

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Model Development to Predict Phenological scale of Table Grapes (cvs. Thompson, Crimson and Superior Seedless and Red Globe) using Growing Degree Days

OENO One ◽

10.20870/oeno-one.2017.51.2.1833 ◽

2017 ◽

Vol 51 (2) ◽

Cited By ~ 3

Author(s):

Nicolas Verdugo-Vásquez ◽

Carolina Pañitrur-De la Fuente ◽

Samuel Ortega-Farías

Keyword(s):

Mean Absolute Error ◽

Model Development ◽

Absolute Error ◽

Growing Degree Days ◽

Degree Days ◽

Independent Variables ◽

Growing Seasons ◽

Table Grapes ◽

Arid Conditions ◽

Linear Correlations

<p style="text-align: justify;">Phenological models have been made mainly for winegrape cultivars, despite the economic importance of table grapes. The aim of this work was to develop and validate models for predicting phenological scales of table grapes (cvs. Thompson, Crimson and Superior Seedless and Red Globe) grown under semi-arid conditions. Measurements of phenology were carried out weekly from budburst to harvest during four growing seasons (2009-2013). Phenology models were developed using the Mitscherlich monomolecular equation where the dependent and independent variables were the Eichhorn and Lorenz phenological (ELP) scale modified by Coombe and the growing degree days (GDD), respectively. Results indicated that there were strong non-linear correlations between the ELP scale and GDD for the four cultivars with coefficient of determinations (R<sup>2</sup>) ranging between 0.97-0.99. Also, validation indicated that the models were able to predict ELP scale with a root mean square (RMSE) and mean absolute error (MAE) ranging between 2.1-2.4 and 1.35-1.69, respectively. The prediction variability (expressed in days) was between 4.4-19.4 days, obtaining the best results for the flowering period. This study suggested that the phenological models based on GDD could be useful planning tools for farming, especially from budburst to veraison of table grape cultivars.</p>

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Assessing the Feasibility of Using Sentinel-2 Imagery to Quantify the Impact of Heatwaves on Irrigated Vineyards

Remote Sensing ◽

10.3390/rs11232869 ◽

2019 ◽

Vol 11 (23) ◽

pp. 2869 ◽

Cited By ~ 4

Author(s):

Alessia Cogato ◽

Vinay Pagay ◽

Francesco Marinello ◽

Franco Meggio ◽

Peter Grace ◽

...

Keyword(s):

Heat Stress ◽

Relative Humidity ◽

Environmental Conditions ◽

Vegetation Index ◽

Growing Degree Days ◽

Degree Days ◽

Absorption Ratio ◽

Red Edge ◽

Medium Resolution ◽

Chlorophyll Absorption

Heatwaves are common in many viticultural regions of Australia. We evaluated the potential of satellite-based remote sensing to detect the effects of high temperatures on grapevines in a South Australian vineyard over the 2016–2017 and 2017–2018 seasons. The study involved: (i) comparing the normalized difference vegetation index (NDVI) from medium- and high-resolution satellite images; (ii) determining correlations between environmental conditions and vegetation indices (Vis); and (iii) identifying VIs that best indicate heatwave effects. Pearson’s correlation and Bland–Altman testing showed a significant agreement between the NDVI of high- and medium-resolution imagery (R = 0.74, estimated difference −0.093). The band and the VI most sensitive to changes in environmental conditions were 705 nm and enhanced vegetation index (EVI), both of which correlated with relative humidity (R = 0.65 and R = 0.62, respectively). Conversely, SWIR (short wave infrared, 1610 nm) exhibited a negative correlation with growing degree days (R = −0.64). The analysis of heat stress showed that green and red edge bands—the chlorophyll absorption ratio index (CARI) and transformed chlorophyll absorption ratio index (TCARI)—were negatively correlated with thermal environmental parameters such as air and soil temperature and growing degree days (GDDs). The red and red edge bands—the soil-adjusted vegetation index (SAVI) and CARI2—were correlated with relative humidity. To the best of our knowledge, this is the first study demonstrating the effectiveness of using medium-resolution imagery for the detection of heat stress on grapevines in irrigated vineyards.

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Effect of Genotype, Planting Date, and Spacing on Zoysiagrass Establishment from Vegetative Plugs

HortScience ◽

10.21273/hortsci.46.8.1194 ◽

2011 ◽

Vol 46 (8) ◽

pp. 1194-1197 ◽

Cited By ~ 1

Author(s):

Bradley S. Sladek ◽

Gerald M. Henry ◽

Dick L. Auld

Keyword(s):

Field Experiments ◽

Slow Growth ◽

Field Studies ◽

Early Summer ◽

Planting Date ◽

Growing Degree Days ◽

Degree Days ◽

Planting Dates ◽

Establishment Rate

Slow growth and establishment rate has become a major limitation to the increased use of zoysiagrass (Zoysia spp.) as a turfgrass surface. Two separate field studies were conducted to evaluate the effect of genotype, planting date, and plug spacing on zoysiagrass establishment. Field experiments were conducted in 2007 and 2008 to quantify the establishment rate of six zoysiagrass genotypes from vegetative plugs. ‘Meyer’ exhibited the largest plug diameter (22 cm) 6 weeks after planting (WAP). In contrast, ‘Diamond’ exhibited the smallest plug diameter (13 cm) 6 WAP. A similar trend was observed 12 WAP. ‘Meyer’, ‘Zorro’, and ‘Shadow Turf’ exhibited the largest plug diameters (60, 58, and 57 cm, respectively) 12 WAP. In contrast, ‘Emerald’ and ‘Diamond’ exhibited the smallest plug diameters (41 and 40 cm, respectively) 12 WAP. Although statistically different, all zoysiagrass genotypes reached similar establishment 18 WAP indicating that plugging these genotypes in a comparable environment and using techniques described in this research may result in analogous long-term (18 weeks) establishment. Field experiments were conducted in 2006 and 2007 to determine the optimum planting date and plug spacing of ‘Shadow Turf’ zoysiagrass. ‘Shadow Turf’ zoysiagrass plugs planted on 28 July 2006 (11% to 65% cover) and 14 June 2007 (5% to 39% cover) exhibited the greatest increase in turfgrass cover 6 WAP, except for plugs planted 15.2 cm apart on 26 May 2006 (74% cover). Zoysiagrass cover was greatest for plugs planted on 26 May 2006 (63% to 100%) and 17 May 2007 (46% to 97%) 16 WAP regardless of plug spacing. These planting dates corresponded to the highest accumulative growing degree-days (GDD) experienced by all planting dates in both years. Plugs planted on 15.2-cm centers exhibited the greatest zoysiagrass cover 6 and 16 WAP regardless of planting date. Using late spring/early summer planting dates and 15.2- to 30.5-cm plug spacings may result in the quickest turfgrass cover when establishing ‘Shadow Turf’ zoysiagrass from plugs.

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Tillage and seed depth effects on velvetleaf (Abutilon theophrasti) emergence

Weed Science ◽

10.1017/s0043174500090202 ◽

1998 ◽

Vol 46 (1) ◽

pp. 76-82 ◽

Cited By ~ 13

Author(s):

Theodore M. Webster ◽

John Cardina ◽

Heather M. Norquay

Keyword(s):

Weed Management ◽

Management Practices ◽

Seedling Emergence ◽

Growing Season ◽

Growing Degree Days ◽

No Tillage ◽

Degree Days ◽

Growing Seasons ◽

Continuous Corn ◽

Emergence Patterns

Understanding patterns of weed seedling emergence within a growing season and over years is important to develop models to predict optimum timing of weed management practices. A study was conducted in a field with no previous velvetleaf infestations to describe emergence patterns following seed burial at three depths in two tillage systems. Freshly harvested velvetleaf seeds were planted 0, 2, and 6 cm deep in moldboard plowed (MP) and no-tillage (NT) corn stubble in October 1990. Velvetleaf seedling emergence was monitored over the following 4 yr in continuous corn. Emergence was higher in NT than in MP plots throughout 4 yr of observation. The first growing season following seeding, emerged seedlings represented 9.3 to 15.8% of the seeds sown in NT, compared with 0.1 to 0.8% of seeds sown in MP. After four growing seasons, emerged seedlings were 12.5 to 25% of seeds sown in NT but only 6 to 7.4 % of seeds sown in MP. Emergence was consistently higher from the 0-cm depth than from the 6-cm depth in NT, but seeding depth did not influence emergence in MP due to mixing of the soil during tillage. Velvetleaf emergence was related to growing degree days (base 7.5 C), with greater consistency in NT than in MP. Averaged over years and planting depths, 50% velvetleaf emergence occurred within 8 and 13 d of the predicted date in NT and MP systems, respectively.

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Early rooting of dormant hardwood cuttings of Populus: analysis of quantitative genetics and genotype × environment interactions

Canadian Journal of Forest Research ◽

10.1139/x05-018 ◽

2005 ◽

Vol 35 (4) ◽

pp. 918-929 ◽

Cited By ~ 44

Author(s):

Ronald S Zalesny, Jr. ◽

Don E Riemenschneider ◽

Richard B Hall

Keyword(s):

Root Growth ◽

Quantitative Genetics ◽

Populus Deltoides ◽

Populus Trichocarpa ◽

Dry Mass ◽

Growing Degree Days ◽

Broad Sense Heritability ◽

Degree Days ◽

Planting Dates ◽

Selection Of

Rooting of hardwood cuttings is under strong genetic control, although genotype × environment interactions affect selection of promising genotypes. Our objectives were (1) to assess the variation in rooting ability among 21 Populus clones and (2) to examine genotype × environment interactions to refine clonal recommendations. The clones belonged to five genomic groups ((Populus trichocarpa Torr. & Gray × Populus deltoides Bartr. ex Marsh.) × P. deltoides 'BC'; P. deltoides 'D'; P. deltoides × Populus maximowiczii A. Henry 'DM'; P. deltoides × Populus nigra L. 'DN'; and P. nigra × P. maximowiczii 'NM'). Cuttings, 20 cm long, were planted in Iowa and Minnesota in randomized complete blocks at 1.2 m × 2.4 m spacing, across three planting dates during 2001 and 2002. We measured nine belowground and aboveground traits from harvested cuttings after 14 days of growth. Percent rooting ranged from 22% to 86%. Broad-sense heritability for root and top dry mass ranged from 0.09 to 0.11 and 0.31 to 0.38, respectively. There were genotype × environment interactions for most traits, with belowground growing degree-days accounting for >54% of environmental variation. Clonal rooting was stable, except at Westport, Minnesota, during 2002, when root growth was relatively poor.

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