scholarly journals Sugar Beet Performance with Curly Top Is Related to Virus Accumulation and Age at Infection

Plant Disease ◽  
2006 ◽  
Vol 90 (5) ◽  
pp. 657-662 ◽  
Author(s):  
William M. Wintermantel ◽  
Stephen R. Kaffka

Resistance to curly top disease caused by Beet curly top virus (BCTV) and related curtoviruses has been important to sustainable sugar beet (Beta vulgaris) production in the western United States for most of the last century. Recent advances in sugar beet genetics have led to the development of high-yielding cultivars, but these cultivars have little resistance to curly top disease. These cultivars are highly effective when disease management practices or environmental factors minimize curly top incidence, but can result in significant losses in years with early infection or abundant curly top. A greenhouse assay has been developed to rapidly test cultivars for a broad array of factors affecting performance in the presence of curly top. Previous studies have shown that sugar beet plants were more susceptible and losses more severe when seedlings were infected by BCTV, but less severe when plants were larger at the time of infection. To evaluate more precisely the relationship between age at infection, disease severity, virus accumulation, and yield loss in modern cultivars that were not bred for curly top resistance, individual sugar beet plants varying in degree of resistance and susceptibility to curly top were inoculated by viruliferous beet leafhoppers (Circulifer tenellus) when plants had two, four, or six true leaves, and maintained in a greenhouse for 6 weeks. When plants were inoculated at the two-leaf stage, all cultivars became severely stunted, with high disease ratings and similar rates of symptom development, regardless of resistance or susceptibility of the cultivar. Plants inoculated at four-and six-leaf stages exhibited increasing separation between resistant and susceptible phenotypes, with highly resistant cultivars performing well with low disease ratings and increased plant weights relative to susceptible cultivars. High-yielding cultivars performed only slightly better than the susceptible control cultivar. Results from greenhouse trials matched those from field trials conducted under heavy curly top pressure. Importantly, low virus concentration was directly correlated with lower disease ratings and higher plant weight, while elevated virus concentrations corresponded to higher disease ratings and lower weights. This demonstrates that a rapid greenhouse assay involving multiple traits can provide a rapid and effective means of selecting cultivars with improved curly top control, and could lead to more rapid incorporation of resistance into high-yielding sugar beet.

Plant Disease ◽  
2005 ◽  
Vol 89 (3) ◽  
pp. 325-331 ◽  
Author(s):  
William M. Wintermantel

Three distinct aphid-transmitted viruses associated with a yellowing disease on sugar beet were examined in single and mixed infections for the effects of virus interactions on plant weight, rate of symptom development, and virus concentration. Sugar beet lines exhibiting different degrees of susceptibility to the virus yellows complex were inoculated with either one, two, or all three viruses. Severe stunting, as measured by fresh plant biomass, was observed with mixed infections with Beet yellows virus (BYV) and Beet mosaic virus (BtMV), compared to single infections of these viruses. In addition, the overall rate of appearance of Beet western yellows virus (BWYV) symptoms increased during co-infection with BtMV. Synergistic effects on stunting severity, as measured by plant biomass, were more pronounced in susceptible beet lines, but similar patterns also were observed in lines exhibiting tolerance to virus yellows. Relative concentrations of viruses were compared among single and mixed infections using dot-blot hybridization with virus specific probes, and quantified by phosphorimage analysis. Titers of all three viruses increased as a result of co-infection compared with single infections.


Weed Science ◽  
1986 ◽  
Vol 34 (6) ◽  
pp. 883-888 ◽  
Author(s):  
Cheo L. Massion ◽  
Steven E. Lindow

Teliospores ofSphacelotheca holciJack. [=S. cruenta(Kuhn.) Potter] infected johnsongrass [Sorghum halepense(L.) Pers. # SORHA) systemically after inoculation of cut stems in greenhouse studies. A preliminary host range test in the greenhouse revealed that no infection occurred on four varieties of sorghum (S. vulgareL.) and three cultivars of sudangrass (S. SudaneseL.). Infected johnsongrass plants grown in the greenhouse exhibited reduced vegetative growth and altered morphological characteristics compared to healthy johnsongrass plants. The aboveground biomass and lateral rhizome expansion of smutted johnsongrass field transplants were significantly lower than that of uninfected plants. Significant correlations between fraction of johnsongrass stems infected and plant weight, and basal area of plants were observed in field studies. Corn (Zea maysL.) and alfalfa (Medicago sativaL.) grown in competition with johnsongrass, and johnsongrass infected withS. holcireduced the aboveground biomass and rhizome length of johnsongrass plants significantly, compared to that of uninfected johnsongrass plants grown alone in greenhouse studies. Uninfected johnsongrass plants also exhibited higher plant weight than infected plants when both were grown in competition with alfalfa, regardless of the alfalfa planting density in the greenhouse or when measured after 3 months in field trials.


2018 ◽  
Vol 28 (4) ◽  
pp. 1281-1284
Author(s):  
Petar Petrov ◽  
Bojan Mitrovski

Due to the great economic significance of the sugar beet, the new production trends are aimed at improving the quantitative and qualitative properties and one of the basic agro technical measures that is directly dependent on the yield and quality of the turnip is the properly conducted plant nutrition. Exporting high quantities of nutrients from the soil, the sugar beet requires application of advanced agro-technology, primarily application of adequate and controlled nutrition and irrigation. Application of this measure, in combination with soil processing, has sustained influence over the following cultures in the crop rotation in terms of nutrients regiment and fight against weeds.In order to determine the effects of mineral fertilizers on sugar beet, field experiment was conducted on fluvisol soil. The experiment is set according to a random block system, following the standard methods of agricultural chemistry for conducting field trials. The experiment includes eight variants, as follows: 1. Control (non-fertilized), 2. NP, 3. NK, 4. PK, 5. NPK, 6. N2PK, 7. N2P2K, 8. N3PK.In the phase of technological maturity of sugar beet, collection of the vegetative material and measurement of the height of the biological yield of the turnips was carried out. Based on the survey results, it can be concluded that the variant N2P2K has achieved the highest yield of swollen roots, i.e. 69.330 kg/ha. The highest yield of leafy greens was achieved in the variant N3PK, i.e. 41.920 kg/ha, which indicates the fact that nitrogen has direct influence over the vegetation mass of sugar beet.


Agronomy ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 291
Author(s):  
Ramón Bienes ◽  
Maria Jose Marques ◽  
Blanca Sastre ◽  
Andrés García-Díaz ◽  
Iris Esparza ◽  
...  

Long-term field trials are essential for monitoring the effects of sustainable land management strategies for adaptation and mitigation to climate change. The influence of more than thirty years of different management is analyzed on extensive crops under three tillage systems, conventional tillage (CT), minimum tillage (MT), and no-tillage (NT), and with two crop rotations, monoculture winter-wheat (Triticum aestivum L.) and wheat-vetch (Triticum aestivum L.-Vicia sativa L.), widely present in the center of Spain. The soil under NT experienced the largest change in organic carbon (SOC) sequestration, macroaggregate stability, and bulk density. In the MT and NT treatments, SOC content was still increasing after 32 years, being 26.5 and 32.2 Mg ha−1, respectively, compared to 20.8 Mg ha−1 in CT. The SOC stratification (ratio of SOC at the topsoil/SOC at the layer underneath), an indicator of soil conservation, increased with decreasing tillage intensity (2.32, 1.36, and 1.01 for NT, MT, and CT respectively). Tillage intensity affected the majority of soil parameters, except the water stable aggregates, infiltration, and porosity. The NT treatment increased available water, but only in monocropping. More water was retained at the permanent wilting point in NT treatments, which can be a disadvantage in dry periods of these edaphoclimatic conditions.


Author(s):  
Róbert Kun ◽  
Dániel Babai ◽  
András István Csathó ◽  
Csaba Vadász ◽  
Nikoletta Kálmán ◽  
...  

AbstractLocal, adaptive traditional grassland management systems have played a fundamental role in the creation, maintenance and conservation of high nature value (HNV) grasslands. The state of diverse HNV grasslands has deteriorated across Europe in conjunction with changes in various management factors, such as management type and management intensity. To conserve the species-rich vegetation of HNV grasslands and to avoid undesirable shifts in plant functional type dominance, it is important to explore the effects of management factors crucial for nature conservation and to adapt them to local circumstances. In our study, we focus on three of the main factors in the management of valuable meadow steppes in the Great Hungarian Plain region (Central Hungary). We studied management types (mowing, grazing and combined), different levels of herbage removal intensity (low, medium, high) and spatio-temporal complexity (low, medium and high) of grassland management. Altogether 172 plots (1 m × 1 m) were designated in 17 sites. Plant diversity indexes and plant functional types were calculated according to the presence and percentage cover of plant species in the plots. Regarding plant diversity and the dominance of plant functional types, herbage removal intensity and spatio-temporal complexity of management had, for the most part, stronger effects than the type of management. Higher spatio-temporal complexity of management resulted in higher plant diversity, while higher intensity of management led to significantly lower diversity. Proper application of type, intensity and spatio-temporal complexity of management practices (separately and in combination) proved to be determining factors in the long-term maintenance and conservation of diversity and species composition of HNV grasslands.


1966 ◽  
Vol 46 (2) ◽  
pp. 141-149 ◽  
Author(s):  
Walter J. Kender ◽  
Franklin P. Eggert

A field experiment using various soil management practices showed that the most effective means to increase blueberry plant spread was through the use of a surface mulch. Peat and sawdust were of equal suitability as a mulching material influencing vegetative growth, although sawdust did result in a reduction in the number of flower buds produced when compared with peat. Mulching was associated with a higher soil moisture content than non-mulched plots.Blueberry plants growing in nitrogen-treated plots had an increased flower bud number and rhizome growth in contrast with those growing in unfertilized plots. Nitrogen fertilization was of particular benefit when applied in association with surface organic mulches.Plants growing in an undisturbed soil were more vigorous than in a homogenized or tilled soil. Sawdust was found to be detrimental to the growth of lowbush blueberry plants when incorporated into a homogenized soil.


2017 ◽  
Vol 47 (3) ◽  
pp. 185-194 ◽  
Author(s):  
Adriano Stephan NASCENTE ◽  
Ruby KROMOCARDI

ABSTRACT The upland rice farmers in Suriname use local varieties and low level technologies in the field. As a result, the upland rice grain yield is low, at about 1 000 kg ha-1. Our objective was to evaluate the use of upland rice cultivars from Suriname and Brazil, and the effect of nitrogen, N, phosphorus, P, and potassium, K, fertilizers on cultivation variables. We undertook four field trials in the Victoria Area, in the Brokopondo District, using a randomized block design each with four replications. The most productive rice varieties were BRS Esmeralda (grain yield 2 903 kg ha-1) and BRS Sertaneja (2 802 kg ha-1). The highest grain yield of 2 620 kg ha-1 was achieved with a top dressing application of 76.41 kg N ha-1 20 days after sowing. For P, the highest grain yield of 3 085 kg ha-1 was achieved with application of 98.06 kg ha-1 P2O5 applied at sowing. An application rate of 31.45 kg ha-1 of K2O at sowing achieved the highest grain yield of 2 952 kg ha-1. Together, these application rates of N, P and K resulted in rice grain yield of about 3 000 kg ha-1, which is three times greater than the national average for upland rice. We demonstrate that the use of improved rice varieties matched to the local conditions, and application of appropriate fertilizers, are management practices that can result in significant increases in rice grain yield in Suriname.


Plant Disease ◽  
2001 ◽  
Vol 85 (7) ◽  
pp. 718-722 ◽  
Author(s):  
Sebastian Kiewnick ◽  
Barry J. Jacobsen ◽  
Andrea Braun-Kiewnick ◽  
Joyce L. A. Eckhoff ◽  
Jerry W. Bergman

Rhizoctonia crown and root rot, caused by the fungus Rhizoctonia solani AG 2-2, is one of the most damaging sugar beet diseases worldwide and causes significant economic losses in more than 25% of the sugar beet production area in the United States. We report on field trials in the years 1996 to 1999 testing both experimental fungicides and antagonistic Bacillus sp. for their potential to reduce disease severity and increase sugar yield in trials inoculated with R. solani AG 2-2. Fungicides were applied as in-furrow sprays at planting or as band sprays directed at the crown at the four-leaf stage, or four- plus eight-leaf stage, while bacteria were applied at the four-leaf stage only. The fungicides azoxystrobin and tebuconazole reduced crown and root rot disease by 50 to 90% over 3 years when used at rates of 76 to 304 g a.i./ha and 250 g a.i./ha, respectively. The disease index at harvest was reduced and the root and sugar yield increased with azoxystrobin compared with tebuconazole. The combination of azoxystrobin applied at 76 g a.i./ha and the Bacillus isolate MSU-127 resulted in best disease reduction and greatest root and sucrose yield increase.


Agronomy ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 2409
Author(s):  
Hamed Alarefee ◽  
Che Fauziah Ishak ◽  
Daljit Singh Karam ◽  
Radziah Othman

Efficient use of co-composted organic manure with biochar is one of the sustainable management practices in an agriculture system to increase soil fertility and crop yield. The objectives of this research are to evaluate the use of co-composted biochar, biochar in formulation with poultry litter (PL), and PL compost on soil properties and maize growth. Organic amendments were applied at 10 Mg ha−1, and synthetic fertilizer was applied at the recommended rate of maize (N: P2O5: K2O at 60:60:40 kg ha−1). The results showed that addition of organic amendment significantly increased the total biomass parameter compared to the control, which ranged from 23.2% to 988.5%. The pure biochar treatment yielded lower biomass than the control by 27.1%, which was attributed to its low nutrient content. Consequently, the application of the co-composted biochar achieved higher plant height and aerial portion, which ranged from 46.86% to 25.74% and 7.8% to 108.2%, respectively, in comparison to the recommended fertilizer rate. In addition, the soil amended with co-composted biochar had a significant increase in soil organic matter and had significantly higher chlorophyll and nutrient concentrations in plants, which increased with an increase in the biochar ratio of the co-composts. This was probably attributed to the release of the nutrients retained during composting, thereby possibly making the co-composted biochar act as a slow-release fertilizer. In conclusion, the addition of organic manure with biochar enhanced the nutrient supply by gradual release in comparison to the mineral fertilizer.


2011 ◽  
Vol 28 (1) ◽  
pp. 36-40 ◽  
Author(s):  
Nathan D. Robertson ◽  
Anthony S. Davis

Abstract The expected production, dissemination, and planting of blight-resistant hybrid chestnut seedlings calls for anticipatory studies to establish optimal management practices. To test phytotoxic potential of a site preparation herbicide, seedling growth and physiological function were measured for potted American chestnut (Castanea dentata [Marsh.] Borkh.). Six concentrations (0.0, 0.026, 0.053, 0.105, 0.158, and 0.210 kg active ingredient [ai] ha−1) of sulfometuron methyl (Oust) were applied to pots in April 2008, which were planted with 1 + 0 seedlings in May, and grown until November 2008. Changes in height, rootcollar diameter, and root volume and length were measured. A portable photosynthesis system was used to measure net photosynthesis, stomatal conductance, and transpiration. Seedlings treated with label-recommended doses (0.105‐0.210 kg [ai] ha−1) showed growth and leaf function suppression, including 55, 71, and 82% reductions in height growth, root volume, and net photosynthesis, respectively. These results indicate that a strong need exists for field trials, with various dose regimes, to be conducted to refine an application rate that minimizes phytotoxic damage while still providing suitable control of competition vegetation.


Sign in / Sign up

Export Citation Format

Share Document