scholarly journals DIVERSITY AND ABUNDANCE OF LANDING APHIDS IN TWO AREAS OF SEED POTATO PRODUCTION IN TUNISIA; RELATIVE TO THE INCIDENCE OF POTATO VIRUSES

Redia ◽  
2020 ◽  
Vol 103 ◽  
pp. 75-85
Author(s):  
AMEN HLAOUI ◽  
EMANUELE MAZZONI ◽  
REBHA SOUISSI ◽  
SONIA BOUKHRIS BOUHACHEM
Keyword(s):  
Seed Potato ◽  
Potato Virus ◽  
Acyrthosiphon Pisum ◽  
Viral Infections ◽  
Virus Transmission ◽  
Potato Production ◽  
Climatic Conditions ◽  
Seed Potato Production ◽  
Potato Viruses ◽  
Chi Square Analysis

Aphid flight activities were monitored in 2015 in two areas of seed potato production in Tunisia. Yellow water traps were used to investigate the diversity of aphidofauna and the incidence of aphids involved in potato virus transmission. A total of 9966 specimens belonged to 73 taxa were captured. The cumulative abundance recorded in Douala (first site) was much higher than in El Ogla (second site) (8768 vs 1189 specimens). The most preponderant species in Douala were Aphis spiraecola Patch (66.1%) and Aphis spp. group (13.5%). In El Ogla Rhopalosiphum padi (L.) comprised 58.9% of total catches, followed by Acyrthosiphon pisum (Harris) (12%) and Aploneura lentisci (Passerini) (10.4%). The highest values of diversity indices were recorded on April 23 th [Shannon-Wiener index (H’)=2.58; Simpson index (1-D)=0.88] in Douala and on May 12th (H’=1.70; 1-D=0.75) in El Ogla. The detection of viral infections by DAS-ELISA determined the predominance of Potato virus Y amongst five main potato viruses tested. Overall Chi-square analysis determined significant differences crossing all areas of seed and ware potatoes and season crops. The highest incidence of viruses was recorded in Douala (18.5%) while El Ogla was under the threshold value (4%). This might be attributed to the occurrence of aphids in early season known previously to be efficient vectors of PVY and to the characteristics of area including climatic conditions, altitude and landscape structure. These results provide new evidence for El Ogla as ideal site to produce healthy tubers while conversely Douala is favourable for the propagation of vectors and viruses.

scholarly journals The effects of monitoring the abundance and species composition of aphids as virus vectors on seed potato production in Serbia

2014 ◽  
Vol 29 (1) ◽  
pp. 9-19 ◽  
Author(s):  
Drago Milosevic ◽  
Slobodan Milenkovic ◽  
Pantelija Peric ◽  
Svetomir Stamenkovic
Keyword(s):  
Species Composition ◽  
Seed Potato ◽  
Potato Virus ◽  
Potato Virus Y ◽  
Potato Production ◽  
Control Measures ◽  
Seed Potato Production ◽  
Potato Viruses ◽  
Plant Infection ◽  
Haulm Destruction

Aphids are the most important vectors of potato viruses during the crop?s growing season. The most widespread and damaging viruses, the potato virus Y and potato leaf roll virus, are transmitted by aphids in non-persistent and persistent manner, respectively. The two viruses cause the greatest concern of potato producers and a great constraint to seed potato production in Serbia, the region and across the world. Potato virus Y is particularly harmful, given its distribution and spreading rate. Seed potato production systems under well-managed conditions involve a series of virus control measures, including the monitoring of outbreaks of winged aphids, their abundance and species composition, in order to forecast virosis, i.e. potential plant and tuber infection periods. Monitoring the aphid vectors of potato viruses enables determination of optimum dates for haulm destruction when higher than normal numbers of winged aphids as vectors of economically harmful diseases have been observed. Haulm destruction in a potato crop reduces the risk of plant infection and virus translocation from the aboveground parts to tubers, thus keeping the proportion of infected tubers within tolerance limits allowed for certain categories of seed potatoes. This practice has positive effects if used in combination with other viral disease control measures; otherwise, it becomes ineffective. This paper provides an integral analysis of the effects and role of monitoring outbreaks of aphids, their abundance and species composition in timing haulm growth termination to prevent plant infection, virus translocation and tuber infestation in potato crops in Serbia and the wider region.

scholarly journals Possible Escape of a Recombinant Isolate of Potato virus Y by Serological Indexing and Methods of its Detection

Plant Disease ◽  
2003 ◽  
Vol 87 (6) ◽  
pp. 679-685 ◽  
Author(s):  
R. P. Singh ◽  
D. L. McLaren ◽  
X. Nie ◽  
M. Singh
Keyword(s):  
Seed Potato ◽  
Potato Virus ◽  
Potato Virus Y ◽  
Simultaneous Detection ◽  
Potato Production ◽  
Rt Pcr ◽  
Seed Potato Production ◽  
Strain Characterization ◽  
Production Area ◽  
Polymerase Chain

Surveys of commercial and seed potato fields for virus diseases (1998 to 2002) in Manitoba established that Potato virus Y (PVY) is of concern in seed potato production. To determine the prevalence of PVY strains, PVY-infected tubers identified by reverse transcription-polymerase chain reaction (RT-PCR) from surveys (2000 to 2001) were grown for symptom expression and strain characterization by strain-specific RT-PCR, bioassays, and serological assays. Of the samples collected (2000 to 2001) and tested by RT-PCR, 4.0% contained PVY. Further analysis of the PVY-positive samples by a duplex RT-PCR facilitating the simultaneous detection of common (PVYO) and tobacco veinal necrosis strains (PVYN/NTN) indicated that 37.5% contained PVYO and 63.5% contained PVYN-type isolates. Analysis of the PVYN-type samples using three monoclonal antibodies (MAbs) showed that all reacted with only the PVYO MAbs and not with the PVYN-specific MAb. Partial nucleotide sequences of both ends of PVY-RNA showed that the PVYN-type isolates resembled those reported in 1996 from Manitoba. These isolates are designated as PVYN:O. In view of the increased incidence of PVYN:O in one production area, seed tubers imported from other provinces of Canada and the neighboring United States were analyzed for PVYN:O. The PVYN:O was detected in imported seeds from Minnesota, Montana, and North Dakota.

Technical Efficiency in Seed Potato Production Systems in Uganda

2018 ◽  
Vol 10 (3(J)) ◽  
pp. 122-140
Author(s):  
Ambrose Rwaheru Aheisibwe ◽  
Razack B. Lokina ◽  
Aloyce S. Hepelwa
Keyword(s):  
Technical Efficiency ◽  
Seed Potato ◽  
Arable Land ◽  
Stochastic Frontier ◽  
Potato Production ◽  
Maximum Likelihood Estimates ◽  
Farm Income ◽  
Seed Potato Production ◽  
Extension Services ◽  
Income Source

This study established the level of technical efficiency and its determinants among the informal and formal seed potato producers in the southwestern highlands agro - ecological zone of Uganda. A multi- stage sampling procedure was employed to select 636 households (499 informal seed producers and 137 formal seed producers) from which data was collected for two seasons using a semi - structured questionnaire. Data was analyzed using the stochastic frontier approach with a one - step approach. Maximum likelihood estimates for the efficiency parameters showed that both informal and formal seed potato producers were not fully efficient. The mean technical efficiency for informal and formal seed potato producers was 8 1 .4 and 80.4 percent respectively. In terms of yield loss, informal and formal seed potato producers respectively lost an average of 981 and 1,208 kg/acre of seed potato tubers due to inefficiency factors . Specifically, off- farm income source, scale of production, seasonal variation, access to extension services and seed producer being male positively influenced informal seed producers’ technical efficiency while producers’ level of education and seed potato variety diversity negatively influenced their efficiency. For formal seed producers, technical efficiency was influenced positively by producers’ education and negatively by household size. The study suggests that there is an opportunity to improve technical efficiency of informal and formal seed producers by 19 and 20 percent respectively. Therefore, this calls for increased investment in developing and promoting high yielding varieties, provision of extension services, input intensification and addressing gender issues in seed potato production in the context of limited arable land .

Suitability of a Cool Maritime Climate for Seed Potato Production

Nature ◽  
1944 ◽  
Vol 154 (3916) ◽  
pp. 644-645 ◽  
Author(s):  
J. E. VAN DER PLANK
Keyword(s):  
Seed Potato ◽  
Potato Production ◽  
Seed Potato Production ◽  
Maritime Climate

scholarly journals Seed Potato Production Business through a Gender Lens

2019 ◽  
Vol 2 (2) ◽  
Author(s):  
Etiang Joseph ◽  
Rose Mwesige ◽  
Sarah Kyarisiima ◽  
Ambrose Aheisibwe ◽  
Kwikiriza Gerald ◽  
...  
Keyword(s):  
Seed Potato ◽  
Potato Production ◽  
Seed Potato Production ◽  
Gender Lens
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