An assessment of the impact of ambient ozone on field-grown crops in New Jersey using the EDU method: Part 1—white potato (Solanum tuberosum)

1990 ◽  
Vol 66 (4) ◽  
pp. 351-360 ◽  
Author(s):  
Bruce B. Clarke ◽  
Barbara Greenhalgh-Weidman ◽  
Eileen G. Brennan
1990 ◽  
Vol 66 (4) ◽  
pp. 361-373 ◽  
Author(s):  
Eileen G. Brennan ◽  
Bruce B. Clarke ◽  
Barbara Greenhalgh-Weidman ◽  
Gretchen Smith

2021 ◽  
Vol 19 (1) ◽  
pp. 63-73
Author(s):  
Aimable Nsabimana ◽  
Fidele Niyitanga ◽  
Dave D. Weatherspoon ◽  
Anwar Naseem

Abstract Rwanda’s “Crop Intensification Program (CIP)” is primarily a land consolidation program aimed at improving agricultural productivity and food security. The program, which began in 2007, focuses on monocropping and commercialization of six priority crops: maize, wheat, rice, white potato, beans, and cassava. CIP has facilitated easy access to improved seed stocks, fertilizer, extension services, and postharvest handling and storage services. Although studies have documented the impact of CIP on changes in farm yield, incomes, and productivity, less is known about its impact on food prices. In this study, we examine the crop-food price differences in intensive monocropped CIP and non-intensive monocropped CIP zones in Rwanda. Specifically, the study evaluates price variations of beans and maize along with complementary food crops in intensive and non-intensive monocropped zones before and after the introduction of the CIP policy. We find that the CIP policy is not associated with differences in CIP crop prices between the intensive and non-intensive monocropped zones. Over time, prices increased for CIP crops but generally, the crop prices in the two zones were cointegrated. Prices for non-CIP crops in the two different zones did show price differentials prior to the implementation of CIP, with the prices in intensive monocropped zones being greater than in the non-intensive monocropped zones. Moreover, the prices in intensive areas are cointegrated with prices in non-intensive areas for maize and beans and these prices are converging. This indicates that farmers who intensively produced one CIP crop were able to go to the market and purchase other food crops and that price differences between zones have decreased over time, potentially making the CIP intensive farmers better off.


1982 ◽  
Vol 99 (2) ◽  
pp. 325-328 ◽  
Author(s):  
M. F. B. Dale ◽  
M. S. Phillips

SUMMARYThe inheritance of resistance to Globodera pallida was studied in seedling progenies derived from Solanum tuberosum ssp. andigena CPC 2802 (H3) and S. vernei and compared with resistance to G. rostochiensis derived from S. tuberosum ssp. andigena CPC 1673(H1). The resistance of CPC 2802 was originally thought to be due to a major gene (H3), but results presented here demonstrate that it and that derived from S. vernei are inherited in a similar manner quite distinct from the major gene inheritance from CPC 1673 (HI). It is concluded that the resistances derived from CPC 2802 and S. vernei are both polygenic in nature. These findings are discussed in relation to breeding policy and screening methods.


2020 ◽  
Vol 10 ◽  
Author(s):  
Edyta Deja-Sikora ◽  
Anita Kowalczyk ◽  
Alina Trejgell ◽  
Adriana Szmidt-Jaworska ◽  
Christel Baum ◽  
...  

2021 ◽  
Author(s):  
Ariel Thomas ◽  
Sönke Reiche ◽  
Christoph Clauser

<p>Offshore fresh groundwater reservoirs have been identified on continental shelves in several regions of the world. In many cases, sea-level change over geologic time-scales has been identified as a key factor in the emplacement of these freshwater systems. This numerical study analyzes a range of paleo-hydrogeological conditions on the New Jersey transect during the late Pleistocene, during which vast sections of the shelf were sub-aerially exposed. Coupled variable-density flow and heat transport simulations were conducted on a geologically representative 2D shelf model using SHEMAT-Suite. The model combines sequence stratigraphic interpretation of 2D depth migrated seismic lines and a stochastic facies distribution, with petrophysical properties derived from IODP Expedition 313 well data. The study considers a 60<sub></sub>000 year period of surface meteoric recharge, and the subsequent marine transgression from 12 000 years ago to present-day. A sensitivity analysis is conducted for key factors that influence offshore freshened groundwater emplacement during recharge phase: (1) topography-driven flow, and (2) permeability anisotropy. Systematically introducing anisotropy resulted in a 11 % – 31 % decrease in emplaced volume relative to the base-case. The results were analysed to determine whether the late Pleistocene sea-level lowstand drove enough freshwater emplacement that can explain the complex present-day observations. All of the simulated scenarios indicate that surface recharge lead to freshening of sediments across the entire transect during this period, even in case of high permeability anisotropy. The observations also suggest that the cyclical flushing and re-salinification of shelf sediments that takes place over glacial – interglacial cycles is an asymmetrical process, which favours storage of freshened pore fluid in the long run.</p>


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