Potato quality inspection app enforces easy QC, manages your potato processing, storage, packing & value adding. Complete potato quality & business management solution.

Potato quality inspection  brochures:  [Potato quality inspection packing]     [Farm management]      [RFID]

Potato quality inspection app.

The farmsoft quality control app for fresh produce fruit & vegetable, seeds, meat, seafood, coffee, herbs, chili quality control & quality management.

Inventory quality control

Manage incoming fresh produce  inventory quality,  capture supplier details and photos, traceability and costs, create inventory & pallet labels, record storage location of inventory.  Bar-code inventory.

Stock-take quality control

Perform stock-takes any time by category or storage location.  Know how much  inventory you have in real time, even search by storage location.  Report by product line and storage location, or product category. 

OPTION:
FARM QUALITY APP

Quality control for farm tasks, farm equipment (tractors, spray rig etc), in field fresh produce QC tests. 

Sales, shipping,  orders

Print pick sheet to pick inventory, or scan inventory / pallets onto orders, or auto select inventory,  or rapidly sell without an order.  Track paid, and unpaid invoices. 

Perform optional quality control tests on fresh produce prior to shipping.

Traceability & recalls

Mock recalls up and down supply chain.   Reduces fresh produce food safety compliance costs, makes audits easy. Optional fresh produce blockchain by CHAIN-TRACE.COM

QC tests relate to specific batches, from specific suppliers from specific farming areas.


Invoices, BOL, labels for pallets & inventory

Choose from a gallery of invoices, bill of lading, freight notes, and industry standard fresh produce labels including Walmart, Tesco, Aldi, Coles, Pick 'n Save, Woolworths and more...

Quality Control tests can be recalled back to a specific invoice if a client has an issue with quality and quotes and invoice number which can be used to find the quality test.

Batch packing

Record all batch inputs such as fruit & vegetables, packaging materials, and other raw materials.  Batch costs automatically tracked.  Batch recalls automatically track suppliers & traceability.

Batch level quality control, lookup QC tests using the batch number.

Logistics

View open orders & balances. Assign orders to specific staff for picking, assign to trucks / driver, transport company.  Set loading order for multiple orders on one truck.  See when orders are ready shipped and print bill of lading, export documents, and invoices. 

Send quality information with shipments.

Quality control

Perform QC tests for incoming pepper inventory, packed, pre-shipping. Configure QC tests for ANYTHING you want to test, supplier quality control tracking.  Attach unlimited photos & documents to QC tests from your cell or tablet.  

Supplier quality control

Rapidly perform quality control tests on fresh produce from suppliers.  Compare the quality  performance of multiple suppliers, and compare quality criteria performance.  Provide quality feedback to suppliers.

Dashboards

Profit:  Analyze profit of each product, individual customer, and batch.  Sales:  Monitor sales progress & shipments.  Quality control dashboard: Internal quality monitoring, supplier performance & more...

Quality control labels

Optionally show a QR code on customer or consumer units that will instantly show the quality control results for that batch of fresh produce.

Value adding

For food service and processors:  specify the ingredients for each product you manufacture, farmsoft will calculate required quantities to fill open orders and schedule the batch.  Quality control tests on all finished product packed.

Unlimited sites & warehouses

Create multiple sites, specify which sites each employee can view (this restricts inventory, orders, invoices etc to selected sites).  Great for businesses with multiple locations across the country or planet.

Advanced tailoring

Add new fields to screens, choose from a wide selection of interfaces (touch based, PC based, data entry, tablet), control special business processes, activate defaults, configure automatic alerts and more...

Purchase order quality control

Order raw materials, packaging materials and more from suppliers.  Analyze orders and prices using Purchases dashboard. 

Perform quality control tests on fresh produce Purchase Order deliveries.

Re-order alerts

Receive alerts when inventory needs to be reordered, analyze inventory that will need ordering in the future, and inventory that is approaching expiry...


Finance apps

Integrate with Xero finance, or export invoices (AR) and Purchase Orders (AP) to your chosen finance app like MYOB, Quickbooks, , FreshBooks, Wave, SaasAnt, SAGE and others...

Unlimited Potato quality control tests

Configure unlimited quality control tests for any fresh produce, meat, seafood, seeds, coffee, chilis, hops...

Rapid Potato quality control

Perform rapid quality control (QC) tests on any fresh produce directly from  your cell or tablet app.

Better Potato packing quality now

Quality control and food safety has never been easier with industry standard quality tests, food safety checklists; or configure your own tests. 

Improve Potato food safety

Farmsoft manages your business wide food safety, as an integral part of the farmsoft fresh produce business management app.

Easy Potato quality traceability

Perform instant mock recalls and audits at any time, from anywhere. No need to compile reports or search for documents. International food safety standards maintained.

Increase Potato inventory quality

Improve management of the quality of incoming fresh produce from the moment it arrives at your pack house.

Improved customer satisfaction from consistent quality Potato 

Customer appreciate consistent fresh produce quality control.

Potato quality control on the production line

In line and end of line fresh produce quality control ensures maximum quality without quality surprises. 

How to influence potato quality
There are three main criteria which define the quality of potato: tuber quality, skin finish and storage and cooking quality. A balanced crop nutrition program is important to help manage all of these criteria.

Tuber quality
Tuber quality, whether it is dry matter content, starch content, internal disorders or cooking ability is critical for the end user.

Nitrogen encourages leaf and tuber growth and maximises starch production, phosphate maintains leaf and tuber growth and influences starch quality and content, potassium maximizes water uptake and dry matter production and can help reduce the level of bruising, calcium minimizes internal rust spot and black spot, magnesium ensures a strong photosynthetic capacity and good growth, boron helps reduce internal rust spot and enzymatic blackening.

Skin finish
Skin finish is becoming more important as consumers increasingly demand potatoes with clean, attractive skins, particularly when buying pre-packed or loose potatoes. Tubers with surface diseases are not only less attractive, they are likely to have a reduced storage life.

Correct balanced nutrition of the plants will reduce the incidence of tuber skin disorders and improve the skin finish. Calcium strengthens tuber skins providing better resistance to diseases, boron enhances the effect of calcium by improving uptake and so and can reduce levels of common scab and other tuber diseases, zinc can minimize powdery scab and sulphur may reduce both powdery and common scab infection.

Storage and cooking quality
Storage and cooking quality cannot be overlooked and once the crop has been harvested the job is not finished as in most countries potatoes have to be stored to provide continuity of supply throughout the year. Tubers that are less prone to bruising or discolouration will store significantly better and retain better cooking qualities.

Correct balanced nutrition of the crop prior to harvest will influence the storage and cooking quality of the potato tubers. Potassium, calcium, magnesium and boron all have positive effect on potato tuber storage and cooking quality by reducing tuber bruising, enzymatic blackening and discolouration.

THE IMPORTANCE OF QUALITY POTATO SEED
IN INCREASING POTATO PRODUCTION
IN ASIA AND THE PACIFIC REGION

1. Introduction
Because of climate change, the reduction of arable land, increasing population, and frequent occurrence of natural disasters, food security has become a crucial issue. To face this situation, increased food supply has become a priority in the world’s development agenda. In terms of nutritional value, adaptability to diverse environments and yield potential, the potato is a preferred crop, especially in developing countries. According to FAO statistics, potato production in developing countries has increased by 94.6 percent over the last 15 years (Table 1). Out of the four major food crops (rice, wheat, potato and maize), the potato has the best potential for yield increases.

Table 1. World potato production in 1991-2007 (million ton)


The potato is grown in more than 150 countries with an average yield of about 16 tons/ha. However, yields in North America and some European countries are over 40 tons/ha; even 70 to 80 tons/ha can be realized in experimental plots. The yield in developing countries is less than 20 tons/ha, even less than 10 tons/ha in some countries. There is a big gap among the various countries between high and low yields, even with the same variety of potato. If constraints could be overcome to some extent, it would be possible to increase the yields in the developing world significantly.

2. Potato yield and the affecting factors
Potato yield is determined both by the crop per se and the environment. The former can be defined as internal causes including genetic identity, health and physiology. The latter are external factors that consist mainly of temperature, light, nutrition and water. The genotype determines tuber number, tuber size and yield potential for any given cultivar. Then, the performance of yield is largely influenced by the health status of seed tubers and plants. The physiological age of seed tubers is also a factor that can affect final yield. Since some external factors (such as light and temperature) cannot be controlled, we can only adjust the inputs of nutrition and water by appropriate fertilizer application and irrigation. Then, appropriate crop management practices should be applied to harmonize the relationship of crop and the environment. It is the only way to get good yields. Unfortunately, we cannot control all external factors, but efforts can be made to optimize yields by using high quality seed.

Genetic identity is modified by breeders through developing new cultivars. Healthy seed is the responsibility of seed producers, and only the physiological age of seed tubers can be adjusted by growers. After reviewing the history of potato breeding, it seems that all registered cultivars have similar yield potential; even some cultivars that have been cultivated for over
100 years can still yield 50 or 60 tons/ha if seed quality is good and, of course, under appropriate crop management. We can say that genotype at present is not a major constraint for getting higher yields. The physiological age of seed tubers can influence yield to a certain extent through adjusting growth speed. Old seed develops fast at an early stage and senesces earlier, which leads to relatively lower final yields. In contrast, young seed develops slowly at an early stage, but it can keep vigour longer and get higher final yields. The range of yield fluctuation adjusted by physiological age is not clear, but yield effects of physiological age are evident. Therefore, it is clear now that seed quality in terms of health and physiological status is a determinant factor of the yield potential of the potato crop.

Crop management practices are related to local conditions, production purposes and utilization, and growers’ experience. In many countries irrigation and fertilizer application are restricted by economic factors. Under these conditions what we can do for yield improvement is just to have healthy seed and good crop management. In fact, high productivity is based on good quality seed, combined with the use of other critical inputs and application of appropriate crop management practices.

3. Effects of good quality seed
Potato yields are affected by several factors. Quality seed is a very important factor. The average yield increase from the use of good quality seed is 30 to 50 percent compared to farmers’ seeds. Two cases from China and the Democratic People’s Republic of Korea can illustrate the differences of yield. The results of investigations carried out in 2005 in Shandong, China are shown in Table 2. In the whole province, the use of good quality seed accounted for 24 percent. Medium quality seed accounted for 43.3 percent; and 32.7 percent of production was based on poor quality seed. The yield difference between good quality and poor quality was 28.4 percent.

Table 2. Comparison of yields from different quality categories of seed



Data from Academy of Agriculture Sciences, DPR Korea, 2007.

The second case, in the Democratic People’s Republic of Korea, shows the yield differences among various classes of seed (Table 3). The basic seed was microtubers. In Class 1 the tubers were harvested in normal size net-houses. In Class 2 the tubers were multiplied in the field.

Table 3. Yield comparison of different classes of seed


Data from Academy of Agriculture Sciences, DPR Korea, 2007.

4. Indicators of potato seed quality
Quality indicators of potato seed have two dimensions: the biological attributes (biological quality) and the appearance attributes (commercial quality). Biological quality is crucial for productivity, whereas commercial quality mainly affects seed price.

4.1 Biological quality
The biological quality includes two aspects: a) the level of disease infection and b) the physiological age of seed tubers. The former is quite complicated and important. It is well known that seed tubers planted continuously for several years will show degeneration. The degeneration is aroused by several kinds of viruses and virus-like organisms. Because of asexual propagation, viruses and viroids can be accumulated in tubers, and lead to degeneration of the potato.

The biological quality includes two aspects: a) the level of disease infection and b) the physiological age of seed tubers. The former is quite complicated and important. It is well known that seed tubers planted continuously for several years will show degeneration. The degeneration is aroused by several kinds of viruses and virus-like organisms. Because of asexual propagation, viruses and viroids can be accumulated in tubers, and lead to degeneration of the potato.

Major viruses affecting the potato are potato virus Y (PVY), potato virus X (PVX), potato virus M (PVM), potato virus A (PVA), potato leaf roll virus (PLRV) and potato spindle tuber viroid (PSTV). Infection of any one alone or some of them jointly would retard plant growth and reduce tuber yield. Apart from viruses, fungal and bacterial pathogens borne by tubers lead to late blight, ring rot, black-leg and others, and are also limiting factors for seed quality.

4.2 Commercial quality
Commercial quality is defined by uniformity and size of tubers, as well as external appearance. For normal production, a reasonable size of seed tuber or tuber pieces should be about 40 to 50 grams. Big size seed will increase cost and seed that are too small can rot before emergence.

4.3 The way to guarantee biological quality
Good biological quality seed is free from any pathogens, including viruses, viroids, fungi and bacteria, that may lead to degeneration of seed. Seed multiplication started with clean stocks should be the key step. After that, appropriate multiplication technology should be applied according to classes of seed multiplied. Figure 1 shows the pattern of the general flow of seed multiplication in most seed production programmes.


Figure 1. General flow of potato seed production

Under given conditions, this flow could be modified. No matter what improvements are made, the quality of seed should be guaranteed. Of course, more generations of multiplication always increase the risk of degeneration, but seed costs can be reduced.

5. Seed supply systems
Seed supply systems are quite diverse. Many seed supply schemes have been adopted by local seed producers especially in tropical and subtropical regions. Some examples used in Asia and the Pacific region are shown below.

5.1 China
China is the world’s foremost potato producer in terms of harvest area and amount. In 2007, the harvested area was five million hectares and total production was 72 million tons. Nevertheless, national average yield was only 14.4 tons/ha, even lower than the world average (16.64 tons/ha). The adverse natural environment such as infertile soil in southwest mountain zones and shortage of water supply in the north-central zones are negative factors, but poor quality of seed is more significant. It is estimated that only 20 percent of the total cultivable area is planted with quality seed (Figures 2 and 3).


Figure 2. Potato seed production scheme in Northern China (single cropping)


Figure 3. Potato seed production scheme in Central China (double cropping)

5.2 Democratic People’s Republic of Korea
During the last ten years, rapid potato development has taken place in Democratic People’s Republic of Korea. Up to 2006, the harvested area was 188 388 hectares and total production was 470 451 tons with average yields of 9.3 tons/ha for spring potatoes and 10.7 tons/ha for summer potatoes. Poor quality of seed is a major constraint on yield increase. For this reason, supply of quality seed became a key issue for potato production. The first step was to install hydroponic facilities to produce mini-tubers of virus free stocks. There are already six tissue culture laboratories equipped with hydroponic facilities around the country. Mini-tubers produced in the laboratories will be distributed to provincial seed farms, and then followed by county seed farms and sub-work teams of cooperative farms. In the northern regions, a four-year multiplication scheme was adopted. In the lowland zones, a scheme of four generations in two years was adopted. As an alternative, true potato seed (TPS) was tried as well for seed production.

Although several approaches to seed multiplication have been tried in lowland zones, the supply of mini-tubers and aphid-proof facilities is still not satisfactory. Sexual reproduction can eliminate almost all pathogens; thus TPS as basic material can be used for seed production. Hybrid or open-pollinated TPS were sowed in July between rows of maize, and harvested in late October. After four to five months of storing, those tubers from TPS can be used as seed for commercial production in lowland zones. All potato clones are heterozygous, and tubers harvested from TPS do not represent a pure variety. However, they are available for family consumption after selection of parental clones (Figures 4 and 5).


Figure 4. Multiplication system in northern region


Figure 5. Multiplication scheme in lowland zones

5.3 Mongolia
In 2004, the average potato yield was only 8.5 tons/ha in Mongolia. Results of interviews with 300 growers revealed that seed quality was the major cause of low yields. Most growers said that they did not know the origin of the seed they planted, as a seed supply system does not exist to which small-scale growers can have access.

From 2005, revitalization of Mongolia’s potato sector (funded by donors) started. Improvement of seed quality was a major component of the project. Based on natural and financial conditions, a decentralized seed system was adopted (Figure 6).


Figure 6. Proposed seed production scheme

Although the system is not perfect, and still needs to be improved in many aspects, it is already showing results. Up to 2006, 103 informal seed producers were operating in 21 aimags (top-level administrative divisions). The average yield reached 10.2 tons/ha. However, technologies for virus detection and quality control are still under development.

6. How to increase the supply of quality seed
The use of quality seed involves two aspects: whether seed of good quality and in large enough quantities can be supplied and whether growers are willing to use quality seed considering the cost—benefit ratio. Both aspects are related to market conditions. The only factor motivating growers to grow potatoes is competitive returns compared to other crops. If higher profits can be achieved, growers would be eager to get quality seed, and then seed producers could have a market for their product. For example, in Shandong, a special area for potato production in China, potatoes can be harvested from late April to June when fresh potato supply is short in most other regions of China. Fresh potatoes harvested in Shandong are easily sold at a good price. Potato growing has become a major source of income for local farmers. Since the profits from increasing yield are higher by using quality seed, growers are willing to buy good quality seed. Shandong has the highest potato yield in China now. Provincial average yield is over 30 tons/ha, with a total harvest area of 1.4 million hectares. Furthermore, Inner Mongolia, which is located on a plateau and has sufficient sunshine, has become a major area for potato production with irrigation facilities. Higher profits from potato growing are encouraging growers to use quality seed.

With the growth of the potato seed market, some large scale seed producers have emerged in recent years. The biggest one is the Shandong Xisen Group, with a capacity of 250 million mini-tubers per year. After multiplication in fields, 75 000 tons of certified seed can be produced yearly. Annual seed production of Inner Mongolia’s Hesheng Potato Industry is already stable at 40 000 tons of certified seed. There are also many small-scale seed producers in China. With the improvement of seed quality, potato yields in China will be significantly increased in the near future.

7. Conclusions
Potato yields are affected by several factors, but the basic factor is seed quality, especially its biological quality. Application of fertilizers and irrigation, as well as appropriate crop management, could be more effective when good quality seed is used.

Good returns from potato production are the driving force for using quality seed. As long as potato growers can achieve higher profits, they are willing to use quality seed. The key is that the profit from using quality seed must offsets its higher cost.

POTATO QUALITY MANAGEMENT
The native potato cultivars ‘Michuñe roja’ (pink fleshed); ‘Michuñe azul’ (purple fleshed); ‘Cabra’ (pink fleshed) and the commercial cultivar ‘Désirée’ (non-colored fleshed) were stored at 4, 12 and 20°C at 85% RH. At harvest and after 2 and 4 months, dry matter contents, total polyphenol contents (TPC), total antioxidant capacity (TAC) by FRAP, glucose, fructose and sucrose contents, were determined. Colored fleshed potatoes had between two and three times more TPC and TAC than the non-colored with no differences among them. The dry matter content was higher than 20% in all of the genetic materials except in ‘Michuñe azul’ with 19%. The values of TAC of colored fleshed potatoes were between 300 and 600 mg equivalent Trolox 100 g‑1 FW at harvest decreasing both at 2 and 4 months (50% less than harvest value). Potatoes stored at 12°C showed higher TAC compared to those stored at 4 and 20°C that did not show differences. The TPC measured on colored fleshed potatoes were not affected by the storage time and the values were between 300 and 400 mg gallic acid 100 g‑1 FW. The potatoes maintained at 20°C presented the highest contents. Glucose levels showed no difference between genetic materials and were not affected by storage temperatures and time (1-1.69 mg g‑1 FW). A similar behavior was observed in sucrose (0.94-1.2 mg g‑1 FW). Fructose levels were higher in potatoes maintained at 4°C (1.4-1.5 mg g‑1 FW) and lower in those kept at 20°C (0.7-0.8 mg g‑1 FW) without differences between genetic materials. The colored fleshed potatoes analyzed are rich in functional compounds and represent an interesting alternative for frying. To preserve the functional quality of the raw material it should be stored up to 2 months at a temperature of 12°C.


POTATO QUALITY SYSTEM
How to Improve Potato Quality With Calcium
Improving Potato Quality is directly influenced by Calcium. Good calcium levels in potato tubers can reduce multiple quality problems including Internal Rust Spot (IRS), internal browning and hollow heart. Calcium also plays a role in reducing susceptibility to bruising and post-harvest diseases. However despite this, farmers do not always get a good response to calcium fertilisers. Here we find out why, what can be done to improve it and how we can use this knowledge to improve potato quality.

Why do potatoes need calcium
Calciums main function within cell walls is to give cell wall rigidity & strength. The most obvious symptom of calcium deficiency is the disintegration of cell walls and the collapse of affected tissues. It’s this tissue collapse that contributes to IRS, internal browning, and premature rotting and bruising post-harvest.

Potatoes don’t actually need very much calcium. The potato quality problems associated with calcium result from tiny local deficiencies, but these minor deficiencies (in terms of the amount of tuber affected) can make crops unsellable.

The Maths should make us ask questions
If a 35t/ha crop of potatoes had complete loss due to internal rust spot, the actual quantity of Ca-deficient tissue (2% of each tuber is actually affected) is only 700kg/ha. The difference between the affected and healthy part of the potato is typically only 4mg/kg.

Therefore the amount of calcium required to prevent an entire 35/ha tonne crop of potato from having internal browning is only 2.8g/ha. This should raise a few questions for growers.

Three Questions to help us understand how to improve potato quality…
Why are small parts of the tuber deficient when the area right next to them isn’t?
Why are these small areas of tissue deficient in Ca when there’s no whole plant deficiency?
How come applying large amounts of calcium doesn’t reverse the deficiency?
In order to answer these questions, it’s important to understand how calcium behaves in a plant. There are two factors to be considered in plant Ca availability –– transport and absorption.

Ca Transport
Unlike most other mineral nutrients, Ca isn’t phloem mobile and can only be transported through the xylem. Ca enters the plant with water and is transported upwards with transpiration, where it’s either absorbed and stored, or is precipitated from the leaves as excess.

Ca only moves upwards. This is why targeting and correct placement of applications is so important. Ca applied to leaves can’t correct problems in the roots.

Therefore, foliar sprays of Ca fertilisers will never put the nutrient into tuber – it’s physiological impossible for the plant to move Ca down.

Ca Absorption
Ca is absorbed into cells using polar-auxin transport –– as auxin moves out of the cell, Ca enters. Parts of a plant that are low in auxin can’t absorb the nutrient effectively, regardless of how much is available.

High auxin-producing areas include new shoots, new flowers, and new leaves. Low auxin-producing areas include fruits, roots and tubers.

This is why applying Ca to correct physiological disorders can be so ineffective. It doesn’t matter how much is applied, parts of the plant with low auxin levels such as tubers can’t absorb it properly and therefore often does not improve potato quality.

So how can we improve tuber Ca levels and potato quality?
Now we have identified the two main drivers in low tuber calcium problems, we can use this to improve our agronomy, and the products we use to help it. Here are some ways we can improve potato quality.

Target the tubers
Don’t apply it to foliage and expect it to get to tubers. For best results it must be placed near the stolon roots inside the tuber zone. Depending on available equipment this can placed through drip lines, or incorporated into hills at planting. Remember that it is the Stolon roots that supply the tubers, the main root system tends to bypass them and take calcium past them and up to foliage, so placing in the tuber zone is crucial.

Target optimum absorption stages
Time applications to when tubers can absorb it. Tubers produce very little auxin once they start growing, so to get conventional Ca sources into a tuber it really needs to be done during the cell division stage. Once tubers reach 5mm in size there’s very little new cell formation, and auxin levels decline. For Ca to be able to get in the tuber it needs to be available between hook eye and 5mm tuber size.

Manage haulm growth
Any weather conditions or agronomic practice that creates rapid vegetative growth will dramatically increase the risk of Internal rust spot and other problems associated with low tuber calcium levels. it is therefore advisable to manage nitrogen applications so as to prevent too much vegetative growth. A good way to do this is to use supplemental applications of Lono which supplies Amine Nitrogen stabilised with LimiN technology which is proven to give a better growth habit where the plant produces a more robust roots system and less top growth. For more information on this you can read Understanding Nitrogen – The key to Potato Yield

This approach has seen good results on varieties sensitive to internal rust spot, but works primarily by creating a ‘shape’ that supplies more Ca to the tuber (growing the stolon roots) and reducing the strain caused by excessive vegetative growth on calcium transport.


POTATO QUALITY INSPECTIONS
Assuring Potato Tuber Quality during Storage: A Future Perspective
M. C. Alamar, Roberta Tosetti, Sandra Landahl, Antonio Bermejo and Leon A. Terry*
Plant Science Laboratory, Cranfield University, Bedfordshire, United Kingdom
Potatoes represent an important staple food crop across the planet. Yet, to maintain tuber quality and extend availability, there is a necessity to store tubers for long periods often using industrial-scale facilities. In this context, preserving potato quality is pivotal for the seed, fresh and processing sectors. The industry has always innovated and invested in improved post-harvest storage. However, the pace of technological change has and will continue to increase. For instance, more stringent legislation and changing consumer attitudes have driven renewed interest in creating alternative or complementary post-harvest treatments to traditional chemically reliant sprout suppression and disease control. Herein, the current knowledge on biochemical factors governing dormancy, the use of chlorpropham (CIPC) as well as existing and chemical alternatives, and the effects of pre- and post-harvest factors to assure potato tuber quality is reviewed. Additionally, the role of genomics as a future approach to potato quality improvement is discussed. Critically, and through a more industry targeted research, a better mechanistic understanding of how the pre-harvest environment influences tuber quality and the factors which govern dormancy transition should lead to a paradigm shift in how sustainable storage can be achieved.

Introduction
Potato tubers (Solanum tuberosum) have been cultivated for more than 6000 years. Currently, potato is the fourth most important crop produced crop worldwide with an annual production of ca. 382 MT. Europe and Asia are the biggest producers with a share of 40.7% each, followed by America and Africa (12.6 and 4.5%, respectively) (FAOSTAT, 20141). Potatoes provide an excellent source of nutrients and vitamins, but year-round availability depends on industrial-scale storage, especially in countries which rely on an annual crop. In the United Kingdom, approximately half of the total harvested tubers are stored for up to 11 months (Dale, 2014). Sub-optimal handling, poor tuber quality, and deficient post-harvest storage can lead to significant amounts of waste. The United Kingdom recorded overall losses of 17% (770,000 tons) in 2012, where premature sprouting and rotting during storage was the main cause of wastage (Terry et al., 2011; Pritchard et al., 2012). The United Kingdom outlined a strategy for a more sustained and secure food system in its Food Standard Agency (FSA) Strategic Plan 2015–2020, which aims, among several targets, to reduce waste (Food Standards Agency [FSA], 2015). This strategy is aligned with consumers’ requirements of improved nutritional value and sensory attributes, and with new regulation demanding the reduction of agrochemical usage (Lacy and Huffman, 2016).

Current challenges in the potato industry include the preservation of tuber quality throughout storage, restriction of isopropyl-N-(3-chlorophenyl) carbamate (chlorpropham or CIPC) residues (mainly for ware potatoes destined for processing), control of sweetening processes, and ensuring tuber marketability (visual appearance is the main factor driving consumers purchase of fresh potatoes; Terry et al., 2013).

Factors Governing Dormancy
Dormancy break in potato tubers is a physiological phenomenon that is regulated by both exogenous (environmental factors) and endogenous signals (Sonnewald and Sonnewald, 2014). The relative concentration of several biochemical compounds such as plant growth regulators [viz. abscisic acid (ABA), auxins, cytokinins (CKs), gibberellins (GAs), ethylene, and strigolactones (SLs)] and other compounds (viz. carbohydrates and organic acids) are believed to orchestrate the onset and further development of dormancy break (Sonnewald, 2001; Viola et al., 2007; Pasare et al., 2013).

Endogenous ethylene is required at the earliest stage of dormancy initiation (endodormancy induction) (Suttle, 1998); however, its role during dormancy and sprouting is still unclear. Exogenous ethylene (10 μL L-1) has been reported to break endodormancy following short-term treatments (Foukaraki et al., 2014), but also to inhibit sprout growth and promote ecodormancy when supplied continuously – either starting immediately after harvest or at first indication of sprouting (Foukaraki et al., 2016a). However, work carried out on cv. Russet Burbank minitubers showed that ethylene was not involved in hormone-induced dormancy break (Suttle, 2009). These findings support the suggestion that the effect of ethylene depends on the physiological state of potato tubers.

The role of ABA is better understood. It is well known that a sustained synthesis and action of ABA is required for dormancy induction and maintenance (Suttle, 2004; Mani et al., 2014). That said, although ABA levels decrease as endodormancy weakens, there is no evidence of an ABA threshold concentration for dormancy release (Biemelt et al., 2000; Destefano-Beltrán et al., 2006; Suttle et al., 2012; Ordaz-Ortiz et al., 2015). It is also known that there is cross-talk between ABA and other phytohormones (Chang et al., 2013), as well as with sugar metabolic pathways, which facilitates the onset of dormancy break and further sprouting (Brady, 2013). Nevertheless, the increase in ABA as a result of exogenous ethylene application has been postulated to delay dormancy break (Foukaraki et al., 2016b). Concomitant to the ABA decline, there is an increase in sucrose contents, which is considered a prerequisite for bud outgrowth (Viola et al., 2007; Sonnewald and Sonnewald, 2014). In this context, auxins are essential for their role in vascular development. Auxins favor the symplastic reconnection of the apical bud region – a discrete cell domain which remains symplastically isolated throughout tuberisation. This reconnection is, therefore, essential for sucrose to reach the meristematic apical bud. High sucrose levels promote trehalose-6-phosphate accumulation (T6P) which supports sprouting probably decreasing sensitivity to ABA (Debast et al., 2011; Tsai and Gazzarrini, 2014).

It has also been demonstrated that, CKs and GAs are required for the reactivation of meristematic activity and sprout growth (Hartmann et al., 2011). Just prior to dormancy break, an increase in both cytokinin concentration and sensitivity have been reported as key factors for meristematic reactivation (Suttle, 2004). Furthermore, CKs coordinated with auxins stimulate sprout elongation (Aksenova et al., 2013). Sensitivity to GAs, which is negatively affected by SLs, increases throughout post-harvest storage and is possibly responsible for sprout vigor (Roumeliotis et al., 2012). SLs may be related to paradormancy establishment instead of eco- and endodormancy since they are key as regulators of lateral bud development (Pasare et al., 2013).

Optimum length of dormancy differs depending on cultivars and final usage of potato tubers. Thus, longer dormancy and delayed sprouting (at a desired time) would be best for ware potatoes storage, while accelerated sprouting would be preferable for seed potatoes. As reviewed by Eshel and Teper-Bamnolker (2012), sprouting has been induced in seed potatoes by the application of “Rinditie” (commercial mixture of ethylene chlorohydrin, ethylene dichloride, and carbon tetrachloride), bromoethane, carbon disulphide, and GAs (Sonnewald and Sonnewald, 2014).

Use of Cipc During Potato Storage
Suppression of sprout growth in potato tubers represents a crucial step to manage potato quality during storage. Sprouting can be inhibited by the application of chemical sprout suppressants and by controlling environmental conditions, e.g., cold storage, tuned humidity and regulated gas composition conditions. Due to its high efficacy, CIPC is the world’s most utilized sprout suppressant chemical; it inhibits meristematic cell division, delaying sprout development. Nevertheless, concerns about CIPC usage have increased following studies which described toxic and carcinogenic properties of CIPC and its metabolites (Balaji et al., 2006; El-Awady Aml et al., 2014). However, evidence on the apparent toxicity of CIPC is sparse.

The use of CIPC is covered by the Code of Practice for using plant protection products (DEFRA, 2006). To deal with the continuous updates and concerns over exceedances in CIPC regulation, the United Kingdom assembled in 2008 the Potato Industry CIPC Stewardship Group (PICSG), which is supported by the potato industry and CIPC-related companies. From July 2017, new legislation came into force establishing that CIPC applications (36 g ton-1 for processing potatoes and 24 g ton-1 for fresh market tubers) must be done through ‘active recirculation’ of storage air by fans to optimize CIPC application (AHDB, 2017). Thus, increasing legislation constraints are driving the potato industry to seek alternative novel technologies which are able to extend post-harvest storage while maintaining tuber quality. Industry aims to provide high quality potatoes with contained costs for storage management; for this reason, it is pivotal to have sprout suppression technologies which can be exploited in the long-term.