On the Hybrid F1 Characteristics of Physiology, Biochemistry, Product Quality and Resistance to Black Shank in Oriental Tobacco

AbstractExperiments were conducted from 1996 to 1998 at the Hefei Institute of Economics and Technology and at the Oriental Experimental Station of the Zhejiang Province (China). Seven F1 hybrids and three parental varieties of Oriental tobaccos were evaluated for the characteristics of photosynthetic and transpiration rates, esterase isozymes, resistance to black shank, quality and product potential from the 1996-1998 growing seasons. Tobacco leaves had higher photosynthetic rates and many differences among genotypes in the early stage of plant vigorous growth compared with more mature leaves. However, transpiration rates were lower in the younger leaves and greater in the more mature leaves. All the entries had four common bands (B1, B3, B4 and B6) of the esterase isoenzymes. Differences between entries resulted from in having or not having the B2 and B5 bands and color intensity differences of all the bands. These differences could be used to identify individual entries. The F1hybrids Samsun X Toy and Samsun X Argjiro, compared with the CK Samsun control, had obvious heterotic vigor in the characteristics of product, for yield, quality and resistance to black shank. The F1 hybrid Samsun X Toy maintained higher photosynthetic and transpiration rates in the two growth stages compared to other entries. However, the F1hybrid Samsun X Argjiro had higher photosynthetic rates and lower transpiration rates in the early growth stage and the two rates were lower in the later stage, but it maintained higher photosynthetic rates for the whole growth stage. Net photosynthetic rates had a significant positive correlation with yield product, quality and resistance to black shank of the Oriental tobacco F1hybrids.

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Rhizopus Head Rot of Confectionery Sunflower: Effects on Yield Quantity and Quality and Implications for Disease Management

Phytopathology ◽

10.1094/phyto.1997.87.12.1226 ◽

1997 ◽

Vol 87 (12) ◽

pp. 1226-1232 ◽

Cited By ~ 13

Author(s):

D. Shtienberg

Keyword(s):

Growth Stage ◽

Field Experiments ◽

Rhizopus Oryzae ◽

Development Stage ◽

Crop Growth ◽

Growth Stages ◽

Yield Quality ◽

Crop Growth Stage ◽

Head Rot ◽

The Individual

The effects of Rhizopus head rot, caused by Rhizopus oryzae, on the yield of confectionery sunflower and its quality were studied in field experiments conducted from 1994 to 1996. The extent of yield loss was related to the crop growth stage at inoculation. When heads were inoculated at the budding stage, loss was not apparent, because inoculated heads were not infected. When inoculated at the anthesis stage, loss was relatively high (42.5 to 99.1%), and both the number of achenes per head and the individual achene weight were reduced. When heads were inoculated at the seed development stage, yield was not reduced significantly (although the entire receptacle was rotted). Effects of Rhizopus head rot on measures of yield quality were examined as well. Inoculation with R. oryzae did not affect the size of the achenes at any crop growth stage. In contrast, the incidence of discolored achenes (an external sign of nutmeats with a bitter off-flavor) was affected by the disease at all crop growth stages. A survey in eight commercial fields from 1992 to 1996 found that, by the end of the season, incidence of disease ranged from 2.3 to 17.4%. However, since disease intensified late, resultant yield losses were minor and did not exceed 3.1%. Loss figures were estimated by means of a model that was developed and validated in the field experiments. The disease did affect the incidence of discolored achenes. Thus, the conclusion drawn is that the effects of Rhizopus head rot in confectionery sunflower on crop yield is of minimal concern, at least when disease intensifies late, as was the case in the studied fields, but management of the disease should be considered in some situations. The objectives would be to prevent a reduction in yield quality, not yield quantity.

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Effect of Harvest Schedule on Organic Kale Grown during the Winter in High Tunnels

HortTechnology ◽

10.21273/horttech04584-20 ◽

2020 ◽

Vol 30 (5) ◽

pp. 570-575

Author(s):

Robert F. Heyduck ◽

Dawn VanLeeuwen ◽

Steven J. Guldan

Keyword(s):

New Mexico ◽

Brassica Napus ◽

Growth Stage ◽

Total Yield ◽

Market Demand ◽

High Tunnel ◽

Mature Leaves ◽

Growing Seasons ◽

High Tunnels ◽

Delayed Growth

We examined the effect of harvest schedule on the yield of ‘Red Russian’ kale (Brassica napus ssp. napus var. pabularia) grown during the winter in 16 × 32-ft high tunnels in northern New Mexico. We conducted the study for two growing seasons: 2013–14 and 2014–15. All plots were sown on 16 Oct. and harvested four times according to four harvest schedules: A) 8, 16, 20, and 24 weeks after sowing; B) 10, 17, 21, and 25 weeks after sowing; C) 12, 18, 22, and 26 weeks after sowing; and D) 14, 19, 23, and 27 weeks after sowing. The first harvest of each treatment was the greatest, averaging 216 g/ft2, compared with 88, 109, and 104 g/ft2 for harvests 2, 3, and 4, respectively. Season total yield of treatments B, C, and D (harvests beginning at 10, 12, and 14 weeks after sowing) yielded significantly more than treatment A, but only in year 2, when delayed growth resulted in very low yields for treatment A at harvest 1. Considering the entire 240-ft2 cropped area of the high tunnel, staggered harvests of 60 ft2 at a time can yield 2.6 to 17.5 kg per harvest or up to 124 kg over an entire season. Although we examined the yield of mature leaves, harvests could possibly begin earlier than in this study for “baby” kale or salad mixes, and the area harvested could be tailored to plant growth stage and market demand.

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Reevaluating the Economic Injury Level for Brown Stink Bug (Hemiptera: Pentatomidae) at Various Growth Stages of Maize

Journal of Economic Entomology ◽

10.1093/jee/toaa173 ◽

2020 ◽

Vol 113 (5) ◽

pp. 2250-2258

Author(s):

Tim B Bryant ◽

Seth J Dorman ◽

Dominic D Reisig ◽

DeShae Dillard ◽

Roger Schürch ◽

...

Keyword(s):

Grain Yield ◽

Growth Stage ◽

Early Stage ◽

Growth Stages ◽

Stink Bug ◽

Infestation Level ◽

Economic Injury Level ◽

Euschistus Servus ◽

Economic Injury ◽

Late Stages

Abstract Economic yield loss and reduction in grain quality from brown stink bug, Euschistus servus (Say), feeding injury in early and late stages of maize, Zea mays (Poales: Poaceae, Linnaeus), development was assessed in Virginia and North Carolina in 2018 and 2019. Varying levels of stink bug infestations were introduced to seedling maize (V2—early stage), and a range of late-stages of maize, including 1) the last stage of vegetative development (V12/V14), 2) prior to tasseling, 3) at tasseling (VT), and 4) across all tested late growth stages. Euschistus servus infestation levels included 33, 67, and 100% of maize seedlings, and 25, 50, 100, and 200% of plants during later stages. Infestations were maintained on seedling maize for 7 d, and 8 or 16 d in reproductive stages. Infestation level in seedling maize had an impact on grain yield. Infestation level and growth stage both had an impact on grain yield in reproductive maize. The percentage of discolored kernels was also affected by infestation level, but not growth stage. Regression analysis between grain yield and infestation level indicated that the average economic injury level is 7% in seedling maize (7 bugs/100 plants) and 12% (12 bugs/100 plants) from the last vegetative stages (V12/V14) through pollination (VT). The economic injury level in the late vegetative stages is only applicable when infestations are present for an extended period of time (16 d), emphasizing the need for continued scouting of maize throughout the season to make informed management decisions.

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A Method of distinguishing the larval Stages of Agriotes sputator (L.) (Col., Elaterid.)

Bulletin of Entomological Research ◽

10.1017/s000748530002770x ◽

1950 ◽

Vol 41 (2) ◽

pp. 395-413 ◽

Cited By ~ 3

Author(s):

Joan F. Basden

Keyword(s):

Growth Stage ◽

Early Stage ◽

Growth Stages ◽

Optimum Size ◽

Quick Method ◽

Stage Number ◽

Larval Stages ◽

Number Of Teeth ◽

Relationship Of ◽

The Relationship

The different instars of Agriotes sputator larvae cannot be distinguished by measurements of total length or of various parts of the wireworm.The number of teeth on the mesothoracic and abdominal spiracles increases with age, and an examination of 700 wireworms showed that the average numbers of teeth on the two thoracic or on all the abdominal spiracles fell into eight groups. These criteria were valid for populations collected at different times of the year.The number of teeth on the thoracic spiracles of a larva in any particular group approximates to that on the abdominal spiracles of a larva in the next larger group.The eight groups formed by counting either the thoracic or the abdominal spiracle teeth represent growth stages and not necessarily instars.The larvae may sometimes moult without growth, a phenomenon probably caused by an inadequate supply of food. At such an ecdysis the number of spiracle teeth does not increase.The larvae pupate after attaining an optimum size, and reach this size in seven or eight growth stages.A quick method of determining the growth stage to which a larva belongs is given, whereby more than 80 per cent, of the larvae are placed in their correct growth stages by counting the teeth on one spiracle only ; for less than 1 per cent, of the larvae is it necessary to examine as many as five spiracles ; an accuracy of more than 97 per cent, can be maintained.The possibility of determining the relationship of growth stage and age is discussed.The division of the larvae into those which will pupate after seven, and those which will pupate after eight growth stages is apparent at a very early stage in the life history. One larva was found which appeared to be in its ninth growth stage.The cause of this difference in growth stage number is unknown. It may be due to the size of the egg, to the time of the year at which hatching occurs, or to heredity.

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Growth Stages Classification of Potato Crop Based on Analysis of Spectral Response and Variables Optimization

Sensors ◽

10.3390/s20143995 ◽

2020 ◽

Vol 20 (14) ◽

pp. 3995 ◽

Cited By ~ 3

Author(s):

Ning Liu ◽

Ruomei Zhao ◽

Lang Qiao ◽

Yao Zhang ◽

Minzan Li ◽

...

Keyword(s):

Growth Stage ◽

Spectral Response ◽

Classification Model ◽

Growth Stages ◽

Potato Field ◽

Spectral Bands ◽

Svm Model ◽

Selection Algorithms ◽

Potato Crops

Potato is the world’s fourth-largest food crop, following rice, wheat, and maize. Unlike other crops, it is a typical root crop with a special growth cycle pattern and underground tubers, which makes it harder to track the progress of potatoes and to provide automated crop management. The classification of growth stages has great significance for right time management in the potato field. This paper aims to study how to classify the growth stage of potato crops accurately on the basis of spectroscopy technology. To develop a classification model that monitors the growth stage of potato crops, the field experiments were conducted at the tillering stage (S1), tuber formation stage (S2), tuber bulking stage (S3), and tuber maturation stage (S4), respectively. After spectral data pre-processing, the dynamic changes in chlorophyll content and spectral response during growth were analyzed. A classification model was then established using the support vector machine (SVM) algorithm based on spectral bands and the wavelet coefficients obtained from the continuous wavelet transform (CWT) of reflectance spectra. The spectral variables, which include sensitive spectral bands and feature wavelet coefficients, were optimized using three selection algorithms to improve the classification performance of the model. The selection algorithms include correlation analysis (CA), the successive projection algorithm (SPA), and the random frog (RF) algorithm. The model results were used to compare the performance of various methods. The CWT-SPA-SVM model exhibited excellent performance. The classification accuracies on the training set (Atrain) and the test set (Atest) were respectively 100% and 97.37%, demonstrating the good classification capability of the model. The difference between the Atrain and accuracy of cross-validation (Acv) was 1%, which showed that the model has good stability. Therefore, the CWT-SPA-SVM model can be used to classify the growth stages of potato crops accurately. This study provides an important support method for the classification of growth stages in the potato field.

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Effect of Herbicides on the Management of the Invasive Weed Solanum rostratum Dunal (Solanaceae)

Plants ◽

10.3390/plants10020284 ◽

2021 ◽

Vol 10 (2) ◽

pp. 284

Author(s):

Jackline Abu-Nassar ◽

Maor Matzrafi

Keyword(s):

Growth Stage ◽

Late Summer ◽

Early Spring ◽

Growth Stages ◽

Weed Species ◽

Invasive Weed ◽

Solanum Rostratum ◽

Stage 4 ◽

Chemical Solutions ◽

Late Growth

Solanum rostratum Dunal is an invasive weed species that invaded Israel in the 1950s. The weed appears in several germination flashes, from early spring until late summer. Recently, an increase in its distribution range was observed, alongside the identification of new populations in the northern part of Israel. This study aimed to investigate the efficacy of herbicide application for the control of S. rostratum using two field populations originated from the Golan Heights and the Jezreel Valley. While minor differences in herbicide efficacy were recorded between populations, plant growth stage had a significant effect on herbicide response. Carfentrazone-ethyl was found to be highly effective in controlling plants at both early and late growth stages. Metribuzin, oxadiazon, oxyfluorfen and tembutrione showed reduced efficacy when applied at later growth stage (8–9 cm height), as compared to the application at an early growth stage (4–5 cm height). Tank mixes of oxadiazon and oxyfluorfen with different concentrations of surfactant improved later growth stage plant control. Taken together, our study highlights several herbicides that can improve weed control and may be used as chemical solutions alongside diversified crop rotation options. Thus, they may aid in preventing the spread and further buildup of S. rostratum field populations.

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Interspecific root interactions enhance photosynthesis and biomass of intercropped millet and peanut plants

Crop and Pasture Science ◽

10.1071/cp18269 ◽

2019 ◽

Vol 70 (3) ◽

pp. 234

Author(s):

Xiaojin Zou ◽

Zhanxiang Sun ◽

Ning Yang ◽

Lizhen Zhang ◽

Wentao Sun ◽

...

Keyword(s):

Crop Yields ◽

Positive Root ◽

Foxtail Millet ◽

Phosphoglycerate Kinase ◽

Plant Productivity ◽

Photosynthetic Rates ◽

Interspecific Facilitation ◽

Growing Seasons ◽

Root Interactions ◽

Root Barrier

Intercropping is commonly practiced worldwide because of its benefits to plant productivity and resource-use efficiency. Belowground interactions in these species-diverse agro-ecosystems can greatly contribute to enhancing crop yields; however, our understanding remains quite limited of how plant roots might interact to influence crop biomass, photosynthetic rates, and the regulation of different proteins involved in CO2 fixation and photosynthesis. We address this research gap by using a pot experiment that included three root-barrier treatments with full, partial and no root interactions between foxtail millet (Setaria italica (L.) P.Beauv.) and peanut (Arachis hypogaea L.) across two growing seasons. Biomass of millet and peanut plants in the treatment with full root interaction was 3.4 and 3.0 times higher, respectively, than in the treatment with no root interaction. Net photosynthetic rates also significantly increased by 112–127% and 275–306% in millet and peanut, respectively, with full root interaction compared with no root interaction. Root interactions (without barriers) contributed to the upregulation of key proteins in millet plants (i.e. ribulose 1,5-biphosphate carboxylase; chloroplast β-carbonic anhydrase; phosphoglucomutase, cytoplasmic 2; and phosphoenolpyruvate carboxylase) and in peanut plants (i.e. ribulose 1,5-biphosphate carboxylase; glyceraldehyde-3-phosphate dehydrogenase; and phosphoglycerate kinase). Our results provide experimental evidence of a molecular basis that interspecific facilitation driven by positive root interactions can contribute to enhancing plant productivity and photosynthesis.

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Corn Yield Loss Due to Volunteer Soybean

Weed Science ◽

10.1614/ws-d-16-00004.1 ◽

2016 ◽

Vol 64 (3) ◽

pp. 495-500 ◽

Cited By ~ 3

Author(s):

Jill Alms ◽

Sharon A. Clay ◽

David Vos ◽

Michael Moechnig

Keyword(s):

Loss Function ◽

Growth Stage ◽

Yield Loss ◽

Corn Yield ◽

Yield Losses ◽

Herbicide Resistant ◽

Growing Seasons ◽

Previous Season ◽

Control Volunteer ◽

Soybean Plants

The widespread adoption of glyphosate-resistant corn and soybean in cropping rotations often results in volunteer plants from the previous season becoming problem weeds that require alternative herbicides for control. Corn yield losses due to season-long volunteer soybean competition at several densities in two growing seasons were used to define a hyperbolic yield loss function. The maximum corn yield loss observed at high volunteer soybean densities was about 56%, whereas, the incremental yield loss (I) at low densities was 3.2%. Corn yield loss at low volunteer soybean densities was similar to losses reported for low densities of velvetleaf and redroot pigweed, with 10% yield loss estimated to occur at 3 to 4 volunteer soybean plants m−2. Several herbicides, including dicamba with or without diflufenzopyr applied at the V2 growth stage of volunteer soybean, provided > 90% control, demonstrating several economical options to control volunteer glyphosate-resistant soybean in glyphosate-resistant corn. Reevaluation of control recommendations may be needed with commercialization of other genetically modified herbicide-resistant soybean varieties.

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Effect of Growth Stage on Susceptibility of Grape Berry and Rachis Tissues to Infection by Phomopsis viticola

Plant Disease ◽

10.1094/pdis.2001.85.5.517 ◽

2001 ◽

Vol 85 (5) ◽

pp. 517-520 ◽

Cited By ~ 25

Author(s):

O. Erincik ◽

L. V. Madden ◽

D. C. Ferree ◽

M. A. Ellis

Keyword(s):

Growth Stage ◽

Grape Berry ◽

Growth Stages ◽

Phomopsis Viticola ◽

Over Time

Intact ‘Seyval’ grape clusters in the greenhouse and ‘Catawba’ clusters in the field were inoculated with conidia of Phomopsis viticola at seven Eichorn-Lorenz growth stages between 12 (prebloom) and 35 (véraison) in 1998. Five pots (10 clusters) were used per inoculation, and the experiment was repeated three times. Also, 10 to 20 randomly selected Catawba clusters were inoculated in the field for each of three replications at each growth stage. Studies were repeated in 1999. In addition, Chambourcin clusters were also inoculated at four growth stages in the greenhouse in 1999. Results obtained in the greenhouse and field during both years and for all cultivars indicate that berry and rachis infections can occur at all growth stages between 12 and 35 with no evidence of decreasing susceptibility over time. Results disagree with some literature reports that indicate that berry infection occurs primarily during bloom and shortly after bloom, and susceptibility decreases as fruit matures.

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Hormesis with glyphosate depends on coffee growth stage

Anais da Academia Brasileira de Ciências ◽

10.1590/s0001-37652013005000027 ◽

2013 ◽

Vol 85 (2) ◽

pp. 813-822 ◽

Cited By ~ 25

Author(s):

LEONARDO B. DE CARVALHO ◽

PEDRO L.C.A. ALVES ◽

STEPHEN O. DUKE

Keyword(s):

Plant Growth ◽

Weed Management ◽

Growth Stage ◽

Growth Stages ◽

Coffee Plant ◽

Herbicide Application ◽

Coffee Plantations ◽

Plant Growth Stages ◽

Coffee Plants ◽

Almost All

Weed management systems in almost all Brazilian coffee plantations allow herbicide spray to drift on crop plants. In order to evaluate if there is any effect of the most commonly used herbicide in coffee production, glyphosate, on coffee plants, a range of glyphosate doses were applied directly on coffee plants at two distinct plant growth stages. Although growth of both young and old plants was reduced at higher glyphosate doses, low doses caused no effects on growth characteristics of young plants and stimulated growth of older plants. Therefore, hormesis with glyphosate is dependent on coffee plant growth stage at the time of herbicide application.

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