Demand For Potatoes Research Articles

Opportunities to Narrow Potato Yield Gaps and Increase Resource Use Efficiency in West Java, Indonesia

AbstractConsumer demand for potato in Indonesia increases while production stagnates. Government policy recognised this discrepancy and prioritised efforts to increase potato yields through farmer support programs with moderate effects to date. This study aimed to decompose potato yield gaps and identify agronomic yield constraints in West Java. Actual yield and management practices of 178 farm registrations over five consecutive growing seasons were analysed with stochastic frontier analysis. The potential yield (Yp) for each registration was simulated with the LINTUL-POTATO-DSS crop model. The overall yield gap was decomposed into its efficiency, resource and technology components. The potato yield gap was 21.5 t ha−1, corresponding to 54% of Yp. The efficiency and technology yield gaps were both ca. 10 t ha−1, corresponding to 26% of Yp, and the resource yield gap was negligible. All fields received sufficient inputs for potential production, but most inputs were used inefficiently. An early first fungicide spray after emergence and frequently spraying to control late blight increased yields significantly. The seed generation planted was critical to potato yield gaps as yield decreased significantly with older generations. Some high-yielding fields, however, were also planted with older seed generations, so other production factors contributed to the yield gap as well. Improving potato yield and reducing current yield gaps in West Java will require well-performed late blight control, the use of high-quality seed and improved management practices, which include reduced input rates.

Research Progress on Fog Cultivation Technology for Potato Seed Production

The market demand for potato seed (minituber) is increasing with the progression and expansion of the potato industry, and the potato seed degeneration has become one of the important factors to restrict the yield and quality of potatoes in the actual development of potato industry. In recent years, the aeroponic cultivation of potato seed has the advantages of high yield and high efficiency as a newly developed virus-free production technology, which effectively solves the problems of soil-borne diseases and continuous cropping obstacles during the potato seed production, as well as opens up a new way for the scalization of potato seed production. In this thesis, the key points of potato seed aeroponic technology, the facility intelligentization development, the core nutrient solution and cultivation management and methods of automatic control of supply system were elaborated, the current problems and application prospects of this technology are summarized based on personal production experience, aimed to provide some foundations for the production as well as practical guidance of potato seed aeroponics cultivation.

Dinamika Usahatani Kentang di Desa Margamulya, Kecamatan Pangalengan

Potatoes are the world's fourth largest staple food after wheat, rice, and maize. In Indonesia, potato farming holds great potential, especially in highland areas like Pangalengan, West Java. However, despite the increasing demand for potatoes, production remains insufficient. The high production costs have led many potato farmers in Margamulya Village, Pangalengan Subdistrict, to switch to other commodities. This research aims to identify the farmers who continue to grow potatoes and examine their farming systems. The study employs a qualitative approach with a case study method, as defined by W. Creswell (2020), focusing on understanding individuals or groups' perspectives on social or human issues. The remaining potato farmers in Margamulya Village are considered to be in their productive age, possessing physical strength and openness to innovation. Most of them have received a high level of education, with many holding bachelor's degrees. These enduring potato farmers have inherited the tradition of potato cultivation and boast strong networks and substantial capital. Their motivation to grow potatoes is high, often described as being "passionate" about potato farming. While their cultivation techniques align with guidelines, they do not strictly adhere to good agricultural practices.

Value chain analysis of potato in Bajhang district, Nepal

The study was conducted in the Bajhang district from February to July 2022. Its goals were to find the key actors in the potato value chain, assess their linkage, analyse marketing margins, determine the share of value-addition among each actor, evaluate the production cost, productivity, and profitability of producers, examine the producer’s share in consumer rupees, and conduct a SWOT analysis. The data collection process involved the random purposive sampling technique to select a total of 80 potato producers, 5 aggregators, 5 wholesalers, 10 retailers, 50 consumers, and 3 extension service providers. Findings revealed that, on average, potato cultivation covered 0.215 hectares (4.23 Ropani) with a productivity of 13.46 Mt/ha, which is lower than the national average. The production cost of the producer was NRs. 301,756.60/Ha (NRs. 15,356.57/Ropani) with a benefit-cost ratio of 1.37, and the producer’s share was 51.68%. The primary value chain actors included input suppliers, producers, aggregators, wholesalers, retailers, and consumers. Marketing margins for producers, aggregators, wholesalers, and retailers were NRs. 359.25/quintal, NRs. 965/quintal, NRs. 945/quintal, and NRs. 1170/quintal, respectively. Value addition by potato producers accounted for 10.45%, while aggregators, wholesalers, and retailers contributed 28.05%, 27.48%, and 34.02%, respectively. The SWOT analysis highlighted opportunities like favourable policies, subsidies, processing options, rising potato demand, and potential production area expansion. To boost the profitability of the potato industry, it is imperative to address challenges such as poor seed quality, diseases-pests, drought, short shelf life, soil degradation, and fertilizer and pesticide availability while strengthening the linkage of value chain actors.

PARTNERSHIP MANAGEMENT AND POTATO COMPETITIVENESS IN BENER MERIAH DISTRICT, ACEH PROVINCE

The research aims to identify supply chain partnerships and analyze potato competitiveness. The research location is in Bener Meriah Regency, Aceh Province. Supply chain partnership management is studied using qualitative and quantitative descriptive approaches. Potato competitiveness was analyzed using the Policy Analysis Matrix (PAM) approach. The research results show that potato farming is quite profitable for farmers and has competitiveness as a superior product. Potato farming partnerships are carried out by farmers at the level of seed procurement and farming costs with a profit-sharing system or general trading pattern through farming capital loans with the condition that farmers must sell potatoes to traders at below-market prices. Potato farming in Bener Meriah Regency has comparative advantages and competitive advantages. It is worthy of development based on the acquisition of PCR and DRCR, both of which have a value of more than one. Potato farming has good prospects for intensive development to increase the competitiveness of potatoes through synergistic partnership programs with downstream business players, considering the high market demand for potatoes and processed potato products.

THE POTENTIAL OF POTATO CULTIVATION (Solanum tuberosum L.) WITH THE APPLICATION OF PLANT GROWTH PROMOTING RHIZOBACTERIA (PGPR) AND TRICHO POWDER COMMERCIAL ON MEDIUM LAND

The market demand for potatoes is very high, and their cultivation can affect the environmental balance, so innovation in potato yield is needed. Medium land is an area with an elevation of 300-700mdpl. Crop yields in medium land are not optimal and more susceptible to disease than highlands. The role of microorganisms in PGPR and Tricho Powder can maximize crop yields and help reduce disease intensity. This study aims to determine the effect of different concentrations of commercial PGPR in increasing the yield of potato cultivation, the effect of different concentrations of Tricho Powder in suppressing the intensity of disease attacks, and find out one species in PGPR. This research was conducted with RAL (6 treatments with 4 replications). The treatments included P0 (Farmers’ Habits), P1 (PGPR 20mL), P2 (PGPR 40 mL), P3 (Tricho Powder 80gram/10Liter), P4 (Tricho Powder 150gram/10L), and P5 (PGPR 20mL+Tricho Powder) 80gr/10L). The data was then analyzed by ANOVA. If there is significance, a follow-up test is carried out, which is determined based on the KK value. The results showed that differences in PGPR concentrations positively affected potato yields with the combination treatment of PGPR 20mL/10L+Tricho Powder 80 gr/10L (P5), which was the best treatment producing the highest mean in each parameter. In the same treatment, disease intensity was reduced by 37.55% compared to the control treatment. Based on its ability to produce IAA from 5 isolates, only 1 isolate (IS 5) showed positive results and was continued to molecular tests.

Profitability and market performance of smallholder potato enterprises in the Eastern Cape Province, South Africa

Potato (Solanum tuberosum) is one of the major staple crops and cash crops in sub-Saharan Africa. Its reputation continues to rise due to the increase in human population and the demand for potatoes is predictable. Potato-produce has a good market reputation and is the major source of household income in developing countries, especially South Africa. However, the increase in potato enterprise comes with its share of challenges that need to be addressed. Smallholder farmers in South Africa are still facing challenges in accessing and participating in lucrative and agro-food value chains, hence their farm returns are very low. There are very few research studies that have assessed the profitability and market performance of potato enterprises. Therefore, this study aimed to investigate the profitability of smallholder potato enterprises in the Eastern Cape Province. A multi-stage sampling procedure was employed to select 160 potato farmers. Primary data were collected using a structured questionnaire. Descriptive statistics, gross margin analysis, benefit-cost ratio and marketing margin analysis were used to analyze the data. The study results reveal that the potato enterprise is profitable and contributes to farmers' well-being. Farmers and sellers determined the price of potatoes. The reason for this market conduct is due to the weak characterization of smallholder farming. Performance analysis established that the total gross marketing and profit margins were highest when farmers sold potatoes to consumers and the lowest when farmers sold to middlemen and retailers. The study recommends that policymakers and government invest in improving infrastructure and educational training of farmers in terms of marketing and taking farming as agribusiness. The study further recommends that policymakers and farm organizations must strengthen institutions that take reliable and timely market information; established potato markets close to the farmers, especially those residing in rural areas. There must be a partnership established between research institutes and universities so that they constantly contribute by releasing high-yielding and disease-resistant varieties to advance the production and productivity of the vegetable sector. The study suggests that there is a need for government involvement to create strong market relations between farmers and consumers and to give suitable training to agricultural extension agents. Key words: Eastern Cape, Food security, Gross margin, Potato enterprise

A review of remote sensing for potato traits characterization in precision agriculture.

Potato is one of the most significant food crops globally due to its essential role in the human diet. The growing demand for potato, coupled with severe environmental losses caused by extensive farming activities, implies the need for better crop protection and management practices. Precision agriculture is being well recognized as the solution as it deals with the management of spatial and temporal variability to improve agricultural returns and reduce environmental impact. As the initial step in precision agriculture, the traditional methods of crop and field characterization require a large input in labor, time, and cost. Recent developments in remote sensing technologies have facilitated the process of monitoring crops and quantifying field variations. Successful applications have been witnessed in the area of precision potato farming. Thus, this review reports the current knowledge on the applications of remote sensing technologies in precision potato trait characterization. We reviewed the commonly used imaging sensors and remote sensing platforms with the comparisons of their strengths and limitations and summarized the main applications of the remote sensing technologies in potato. As a result, this review could update potato agronomists and farmers with the latest approaches and research outcomes, as well as provide a selective list for those who have the intentions to apply remote sensing technologies to characterize potato traits for precision agriculture.

Production and availability of good quality seed potatoes in the East African region: A review

Demand for potatoes has grown rapidly in eastern Africa due to rapid population growth, urbanisation and life style changes. This has made potato an important commodity crop in the region contributing to food security and enhanced livelihoods. However, potato productivity in the region is low; ranging from 6 to10 t/ha against potential yields of over 30 t/ha. One of the major causes of low yields is the chronic shortage of good quality seed potatoes for planting, which also limits adoption of new and improved varieties. Therefore, the objective of this paper is to highlight the opportunities and progresses in the production and availability of good quality seed potatoes in the East African region to bolster the productivity and commercial value of the crop. The first section of the paper discusses the status of good quality seed potatoes production and availability in the East African region. The second section looks at the farmer-based seed potato production technologies while the third section focuses on the efforts of both the private and public sector in production of good quality seed potatoes. Availability of good quality seed potatoes constitutes < 1% of the requirement in eastern Africa. These seeds are mainly produced by public research institutions as well as some private players. Consequently, most farmers opt to plant seed potatoes from informal sources. However, seeds from informal sources are mostly of poor quality and often accelerate the spread of tuber-borne diseases, especially viruses and bacterial wilt. To improve seeds from informal system, some technologies have been identified and promoted to enhance farmer-based seed production and distribution. These include seed plot technology (SPT), positive selection techniques (PST) and Quality Declared Seed (QDS) systems. In addition, there has been adoption and promotion of rapid multiplication techniques (RMT) such as stem/shoot cuttings, aeroponics, sandponics, and hydroponics among others. Other measures that have been taken include importing seeds of new potato varieties. The imports increase the quantity of seeds and the number of potato varieties available to farmers. Despite these efforts, the quantity of good quality seeds available is still far below the requirements. There is need for the governments, private sector players as well as farmers to enhance their efforts and save the situation. Governments need to invest seriously in local breeding activities and multiplication of early generation seeds. These and other measures may increase availability of good quality and affordable seed potatoes in East African region.

USING BIOPREPARATIONS TO OPTIMIZE POTATO NUTRITION IN THE SOUTHERN STEPPE OF UKRAINE

Potatoes in Ukraine belong to the main food crops, it is used for food throughout the year for the high nutritional quality of tubers. However, despite the significant demand for potatoes, its yield remains low and there is a need to improve the technological methods of the crop growing, which contribute to both increasing the production of tubers and improving the main indicators of their quality. The article presents the results of research conducted in 2017-2019 years on improving the nutrition of potato varieties by drip irrigation on southern Chernozem. It was determined the positive influence of mineral fertilizers and foliar nutrition on the background of application of modern biopreparations in the main periods of vegetation of plants on the level of yield of tubers and their quality. It was found that the yield of tubers under the influence of nutrition in the potato variety Minerva grew in the range of 3.0 up to 13.2 t/ha, and in the Riviera variety the yield of tuber grew from 3.2 up to 12.6 t/ha, or respectively by 18.0-79.0% and 16.4-64.6% depending on the variant. In addition to the increase in the yield level, the main properties of tubers were improved by optimizing nutrition - they increased the content of dry substance, vitamin C and starch, the conditional yield of starch per unit area increased, and, if the tubers were processed, the yield of alcohol and bioethanol increased.

Non-linearity in Marginal LCA: Application of a Spatial Optimization Model

Typical applications of LCA assume that the magnitude of life-cycle impact grows proportionally to the volume of demand, while in reality the additional impact due to marginal increase in demand may differ from the average impact. In the literature, the calculation of marginal life-cycle impacts often involves the use of optimization models, where typically the total economic costs are minimized. However, modeling spatially explicit marginal responses of a system involving multiple producers and consumers has not been discussed in LCA literature. In this paper, we demonstrate a spatial optimization technique for modeling marginal responses of a multi-producer, multi-consumer system. Our model determines the optimal production-by-location mix and associated environmental stressor at minimum systems cost. We demonstrate the model using a preliminary case study on blue water consumption by potato. We collected state-by-state data on potato yield, cost of potato production, and water use for irrigation, as well as interstate transportation fuel costs. We also estimated the marginal increase in demand for potato following USDA's recommended diet. The results show that the cradle-to-gate blue water consumption of potatoes based on 2016 demand was 96 m3/ton potato, which changes non-linearly along with the growth of potato demands. In order to meet the USDA's recommended diet, the additional demand on potato (530,000 ton per year) would result in a 29% lower blue water consumption per ton of potato (68 m3/ton) as compared to the average result of the current production system. In addition, we tested the model to analyze the marginal impacts under two scenarios: (1) high fuel tax and (2) high water price. The preliminary results indicate that water pricing is more effective than a fuel tax increase in reducing the marginal blue water consumption of potato based on our scenarios of the recommended diet demand. The results demonstrate that our model can be used to understand the non-linear behavior of marginal effect over demand crease, and for testing alternative policy scenarios involving a system with multiple producers and consumers across regions.

Study on sweet potato market behaviour in supporting food security

Sweet potato has an important role in food security. In the future, the demand for sweet potatoes will become higher. However, there has not been any significant awareness of sweet potatoes’ importance; moreover, it is considered an inferior commodity. New improved varieties of sweet potato having high beta-carotene, namely Beta 1 and high anthocyanins, Antin 2 and Antin 3 are already available. Besides, Pating 2 has high starch and dry matter (> 30%) as well as high potential yield (30-40 t ha−1). Sweet potato condition is indicated by its market behaviour described by market elasticity and integration. Sweet potato demand is inelastic, and the price level is inversely proportional to demand quantity. The cross elasticity showed rice was the strongest substitute for sweet potato. The negative value of income elasticity meant the decrease of sweet potato consumption would follow the increase in income. Similarly, the integration of production centres inter-regional market has not been well ordered, distorting product distribution. Suggestions for the sweet potato market included exploiting its potential as a functional food by promoting and community education, diversifying the products, structuring the market for distributional purpose, creating market regulation, issuing price stabilization policy, and improving marketing infrastructures.

Producing more potatoes with lower inputs and greenhouse gases emissions by regionalized cooperation in China

The Chinese government has projected that 30% of the total potato consumed as a staple food, to meet the yield demand for staple food anticipated by population growth and the recommended tuber consumption for a healthful diet. This policy has significantly promoted potato development in China in recent years. Nevertheless, it is urgent to determine where is it suitable to grow potatoes in China and how to match the future demand for potatoes with lower inputs and environmental costs. In the present study, we compared the integrated efficiencies of the six Chinese potato-production regions by analyzing the normalization scores of the Partial Factor Productivity of new nitrogen (N) and phosphorus (P) inputs (PFPN and PFPP), and greenhouse gas (GHG) intensity (GHGI) indicators, to reply to the first question. Then we predicated the national potato demand based on the historical trends of per capita tuber consumption in China’s urban and rural areas, and estimated the national new N and P inputs, irrigation water consumption, and total GHG emissions when meeting the future potato demand, by scenario analysis, to answer the second question. We found that the Chinese mean per capita tuber consumption is expected to rise to the recommended standard (50 g cap.−1 d−1) by 2026. If current increasing trends continue, potato yield will need to increase by 42.2% relative to 2015. The normalization score of the PFPN, PFPP, and GHGI indicators shows that northeast (NE, 3.0), northwest (NW, 1.4), and southwest (SW, 1.1) China have considerable advantages for growing potatoes, compared to the middle and lower reaches of the Yangtze River (MLRYR, 0.3), southeast China (SE, 0.4) and north China (NC, 0.1). Chinese potato production has the potential for mitigating total potato-sown area, new N and P inputs, irrigation water consumption, and total GHG emissions by 1.6–7.7%, 2.2–11.1%, 2.3–11.2%, 1.0–5.1% and 6.7–33.3%, respectively, relative to a business-as-usual scenario, with no compromise in yield. The combined measures include converting a small proportion of maize land to potato production in the NE, NW and SW regions, properly increasing winter potato planting after the late-rice season in MLRYR, SW and SE, and enhancing potato yield by adopting optimized agricultural practices in the six production regions. The proportions and combinations in which these three measures are promoted depend on the degree of difficulty for each region. Our results can not only help guide potato farming toward lower inputs and cleaner production in China by regionalized cooperation, but can also provide regionalized parameters for resource inputs and GHG emissions for further simulation models of Chinese potato production.

PROMISING EARLY PLANTING AND STRESS-TOLERANT POTATO GENOTYPES FOR NORTHERN BANGLADESH

Potato is the third major food crop in the world. In Northern Bangladesh, potato production outside the regular growing season can contribute to farmers’ profit and prices can be very favorable as consumers’ demand for potatoes is greater than the decreased, off-season supply. However, potato production may be negatively affected by increased pest and disease pressure and higher soil temperature. We hypothesized that some potato varieties would have smaller tuber yield reduction when they are grown outside the normal season. The objective of this experiment was to find out promising genotypes for earlier cultivation prior to mid of November, cultivation in northern regions of Bangladesh. The trials, corresponding to very early, early, normal and late growing seasons were planted using a randomized complete block design with three replications. Germination percent, plant height, stems per hill, marketable tuber yield at 65 days, marketable tuber yield at 90 days were recorded. For yield and components of yield contributing characters Clone 13.17, BARI Alu 7(Diamant) and Arizona outperformed in all growing condition and had wider adaptability and stability of tuber yield based on Additive main effects and multiplicative interaction (AMMI).

Three-dimensional Numerical Simulation of the Flow Field in the Potato Storage in Summer

In recent years, with the rapid growth of potato demand, potato storage has become extremely important. It is vital that controls the ambient temperature and wind speed during potato storage. Therefore, this work simulated the temperature field and air flow organization in a potato storage using the underfloor air supply. The established computational fluid dynamics (CFD) model was used to study the temperature field and airflow organization in the warehouse under different air supply parameters, and compared the results to get their change rule. On this basis, the influence of the underfloor air supply on the flow field was studied to verify its feasibility. The results show that under reasonable conditions, the underfloor air supply can effectively guarantee the required temperature and airflow organization.

Respon Dua Varietas Tanaman Kentang (Solanum tuerosum L.) Terhadap Aplikasi Pupuk Majemuk NPK

Demand for potatoes from time to time is increasing. Therefore it is necessary to increase the productivity of potatoes through appropriate cultivation techniques especially in new potato varieties. This study aims to determine the effect of NPK (16:16:16) fertilizer dosage on the growth and yield of two potato varieties in the highlands.The design used was factorial Randomized Block Design (RAK) using 2 factors. The first factor was the aplication of NPK fertilizer with 3 levels, namely P0 = without fertilizer, P1 = 400 kg fertilizer NPK ha-1 and P2 = 800 kg NPK fertilizer ha-1. The second factor is the type of variety with 2 levels, V1 = Granola L and V2 = Granolla Arjuno. Of these two factors, there were six treatment, Each treatment was repeated 3 times. There are two observed variables which are growth variables (plant height, number of stems, number of leaves and stem diameter) and yield variables (number of tubers, weight of , tuber per plot and per hectare). The data collected was analyzed based on F Test at the level of 5% and LSD test 5%. The results showed that the best plant growth was Granolla Arjuno variety with a dose of NPK fertilizer 400 kg ha-1 (P1V2). While the treatment that gives the highest results is Granolla Arjuno variety with a dose of N-P-K fertilizer 400 kg ha-1 (P1V2)

РОССИЯ В МИРОВОМ ПРОИЗВОДСТВЕ И РЫНКЕ КАРТОФЕЛЯ И ПЛОДООВОЩНОЙ ПРОДУКЦИИ

In 1961-2018 in the world as a whole, the gross harvest of potatoes increased from 290.6 million tons to 368.2 million tons, that is, 1.36 times. Over the same period, the production of vegetables and food melons increased from 197.7 million tons to 1,088.8 million tons (5.51 times), and fruits and berries from 199.9 million tons to 867.8 million tons (4.34 times). In a number of states in 1992-2018 the corresponding increase significantly exceeded the average values for the world as a whole, as a result of which their place in the global ranking increased, and the positions of some traditional producers of potatoes and fruits and vegetables decreased. For example, in terms of gross harvest of potatoes in 1992, Russia was in first place, and Poland was in third, while in 2018 they were in 4th and 9th positions, respectively. In terms of vegetable production, Italy and Japan were displaced from 4th and 5th places, which were taken by Turkey and Nigeria. In terms of gross harvests of fruits and berries, Turkey occupied the fifth position in total world production by 2018, although in 1992 it belonged to Italy. Quantitative and qualitative changes inevitably have a significant impact on both the volume of the world market and the parameters of international trade in potatoes, vegetables and melons, fruits and berries. Processes in foreign economic liberalization and economic integration contributed to an increase in the specialization and concentration of production of relevant plants in countries with more favorable natural and climatic conditions, as well as a gradual increase in demand for potatoes, vegetables and melons, fruits and berries from a number of states, including those that used to meet the needs of their population in large volumes at the expense of their own producers. The Russian Federation is one of the significant players in the world potato and fruit and vegetable market. Despite the increase in gross fruit and vegetable production in recent years, Russia’s positions in the global rating dropped from 7th to 10th place in vegetables and melons, from 20th to 31st place in fruits and berries. As for potatoes, there was a decrease in the volume of its production, as a result, Russia dropped from 1st place in 1992 to 4th place in 2018.

Analysis of technical efficiency of potato (Solanum tuberosum L.) production in Chilga District, Amhara National Regional State, Ethiopia

BackgroundPotato is one of the major staple crops in the Eastern and Central Africa sub-region. Its importance continues to rise due to increased urbanization and demand for potato is projected. This increase will definitely come with its share of challenges that need to be addressed. This study was aimed to measure the level of technical efficiency, yield loss due to inefficiency and identify the factors that influence the efficiency levels of potato producers’ in Chilga District. Primary data were collected from 150 farmers selected using multistage sampling procedure and analyzed using descriptive statistics, a parametric stochastic frontier production function models.ResultsThe results of the study indicated that the minimum, maximum and average yields of potato production in the sample households were 1000, 36,000 and 13,108 kg/ha, respectively. The stochastic frontier and Cobb–Douglas functional form with a one-step approach was employed to analyze efficiency and factors affecting efficiency in potato production. The mean technical efficiency (TE) was found to be 46%, and about 17,782.43 kg of potato output per hectare was lost due to inefficiency factors implying there is a room for improvement in technical efficiency by 54% with the present technology. The Stochastic Production Frontier (SPF) result revealed that DAP at 5% and Oxen, MDE and seed at 1% probability level significantly influencing potato production. The socio-economic variables that exercised important role for variations in technical efficiency positively were age and improved seed and nevertheless distance to market was found to increase inefficiency significantly among farm household.ConclusionsThere is considerable difference in the efficiency level among plots. Hence if inputs are used to their maximum potential, there will be considerable gain from improvement in technical efficiency. The estimated SPF model together with the inefficiency parameters shows that age and improved seed variety were influenced by inefficiency negatively whereas distance to market increased the level of technical inefficiency.

Changes in potato tuber sugar metabolism in response to natural sprout suppressive compounds

The increased demand for potato by the Brazilian processing industry requires long term refrigerated storage, but after a few months, natural dormancy ends, and sprouts start to grow. Thus, sprout inhibitors are necessary to reduce the rate of growth and allow further storage. The purpose of research described here was to determine the effects clove and menthol essential oils have on the inhibition of sprout growth in non-dormant ‘Asterix’ tubers. Both eugenol and menthol treatments reduced the rate of sprout growth during storage at 8oC for up to 50 days. Eugenol and menthol essential oils diminished the rate of accumulation of reducing sugar, which are responsible for browning of French fries. Color after frying was within acceptable levels when the tubers were treated with eugenol or menthol essential oils.

COMPETITIVENESS OF THE EGYPTIAN POTATO IN THE MAJOR EXPORT MARKETS

The main objective of the research is to shed light on the competitive position of Egyptian potato exports and the most important countries competing in the export of onions during the period (2002 - 2017) in the most important export markets. The results show that Egypt has a relatively high comparative advantage of potato exports compared to the rest of the exporting countries with an average of about 18.7 in the period (2002-2017), which indicates that there is an opportunity to expand and increase Egypt's potato exports to the world. .A study of the geographical distribution of Egypt's potato exports revealed that the Russian market ranked first in quantity and value of Egypt's onion exports. Followed by the Italian market in that period. According to the market share, Egypt occupies the first place among the major exporters of potato for the Russian market, accounting for 29.3% of the Russian market and about 7.4% of the Italian market. The relative increase in potato production for Egypt compared to the most competitive countries in the Russian market and the Italian market. The index of the market penetration of Egyptian potato in these markets indicated that Egyptian exports to these markets could increase. Potato demand was also estimated in the most important markets for the Egyptian potato, the Russian market and the Italian market. The most important determinants of demand for Egyptian potatoes in the Russian market, which has a positive impact of positive, The export price of Azerbaijan Potato to the Russian market in dollars, While there was a significant inverse correlation between the amount of Egyptian potato exports to the Russian market and the price of Egypt's potato exports to the Russian market in dollars, while the determinants of demand for potatoes in the Italian market, which have a negative impact of significance. Italian imports of potatoes from other countries, Italy's production of potatoes, these factors were statistically significant.