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Are sizes of potatoes normally distributed?

Are sizes of potatoes normally distributed?



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I'm currently researching the variability of sizes of potatoes when all of the potatoes in question have been harvested from a single field. One question keeps coming up in my statistical analyses: Under normal circumstances, are the sizes of potatoes - within a single field - normally distributed? (Please feel free to define the weasel words "normal circumstances" in the most helpful way you can imagine.)

Human height is often given as one of those classic examples of a normally distributed phenomenon. The little that I know about plant biology suggests that the central limit theorem applies just as much to potatoes as to the human body: the lengths of potato tubers and the lengths of human bones should have similarly-shaped distributions. But is that correct?


A bit of context to my original question: what I'm trying to do is to take the mean and standard deviation of my data and then, using the 68-95-99 rule, construct a series of confidence intervals, which I can then test or refine by looking at other data sets. Obviously, no real data set is going to conform perfectly to a model; I just need to know that, in principle, potato sizes are normally distributed enough that my method for drawing up confidence intervals isn't hopelessly misguided.


According to Evaluation of the Effect of Density on Potato Yield and Tuber Size Distribution potato tuber size was estimated using a normal distribution but they are not normally distributed

They found that a Weibull distribution with specific parameters estimated better than a normal distribution.

In fact you should not expect a normal distribution because there are no potatoes of negative size As such you expect a gamma distribution. The Weibull distribution is in the same family of distributions.

But in many cases the normal distribution is used since the probability of a negative number is negligigble.

Does this mean that potato sizes are still the result of many factors? It would seem so


NATURAL ANTI-MICROBIAL SYSTEMS | Antimicrobial Compounds in Plants

Potato and Tomato

Solanine (8) from potato (Solanum tuberosum) and α-tomatine (9) from tomato (Solanum lycopersicum) are both steroidal saponins. They contribute to the protection of the plants against attack by phytopathogenic fungi. In vitro, both solanine and tomatine caused the disruption of model membranes, possibly by the insertion of the aglycone moiety into the lipid bilayer. Solanine is toxic and has fungicidal and pesticidal properties, and it is one of the plant’s natural defenses. It can occur naturally in any part of the plant, including the leaves, fruits, and tubers. Tomatine, which has fungicidal properties, is toxic and found in the stems and leaves of tomato plants. Some microbes produce an enzyme called tomatinase, which can degrade tomatine, rendering it ineffective as an antimicrobial.


Potato Starch

Cindy Semeijn , Pieter L. Buwalda , in Starch in Food (Second Edition) , 2018

Abstract

Potato starch and its derivatives are of major commercial importance because they govern the texture and hence the liking of food stuffs. The mode of actions of starches is governed by the granular and molecular architecture of the starch and the interaction with the food processing. In this chapter an overview is given of the starch characteristics of normal and waxy potato starch in comparison to other starches. Furthermore an overview of derivatizations is presented and their impact on the processibility during food production. The chapter ends with an outlook on future trends in starch-altering methods.


Symptoms of Late Blight in Potato

The infection or late blight in potato may occur in any stage of the plant growth. The signs and symptoms of late blight in potato includes the following:

  1. The appearance of watery, light green or yellow blisters on the leaf foliage.
  2. Lower leaf develops brown, black lesions.
  3. In certain areas of the plant, leaf blistering may occur.
  4. Within several days (generally 1-4), leaf rotting occurs by the development of tan coloured blisters (in dry weather) and growth of blue-grey mycelium (in moist weather).
  5. Later, the leaf starts falling and cause rotting in tubers as well. Rotting in tubers are of two types:
    • Dry rot: The potato tuber develops bluish-black growth outside, and becomes reddish brown inside. P. infestans causes 5-15mm deep rotting in the tuber.
    • Wet rot: The potato tuber develops the growth of white colonies outside and secretes water. P. infestans causes 24-45mm deep rotting in the tuber, or we can say it can affect the whole potato.

If no one follows the control measures for the disease management, then the whole field may be affected, and also emits an offensive odour.

Disease Cycle

The asexual mode of disease cycle occurs via sporangia either indirectly by the zoospores or without an intermediary through the germ-tube formation. The sexual mode of disease cycle occurs through the oospore, resulted after the fusion of oogonium and anthredium. Generally, the asexual phase is more common. Lesions or blisters develop in the seedlings or tubers by the attack of fungus (P. infestans).

The fungus may disperse into the new infection sites, and then a fungal mycelium develops sporangia. In wet conditions, the sporangia form biflagellate zoospores within three to five hours and requires 12 hours of free moisture. On unfavourable condition, the sporangia wall bursts out to release free zoospores.

The biflagellate zoospores of P. infestans can survive in dry conditions for an hour and even more in cloudy weather. Zoospores encyst and can indirectly infect the host cell wherever they fall via wind or rain transmission.

In dry weather, sporangia acts as an individual spore that can form a germ tube to directly invade the plant cells. The sporangia germinate to get into the different cellular components.

The sexual phase of P. infestans involves diploid oospores, resulted after the nuclear fusion or karyogamy between the male antheridium and female oogonium. Later, the oospores germinate to develop sporangia, which then follows the same pathway as we can see in the above diagram.

Phytophthora infestans has a high reproductive potential that can produce 1 to 3 lakhs sporangia per day from an individual lesion. Then every sporangium can start a new infection with the visible symptoms. Lesions in the form of small or wide patches appear on the leaves and stem after an incubation period of a few days.

Therefore, the high growth rate of the P. infestans can cause rapid defoliation and destruction of foliage and tubers. If the management of the disease is not established correctly, then the pathogen might destroy the whole field in a short time.

If the tuber gets infected with such fungus, then the whole seedling will become diseased. In this way, the disease cycle revolves around that occurs every five to seven days, resulting in dissemination of the late blight infection.

Control

The disease management of late blight in potato includes the following:

  1. We must use healthy or resistant varieties of seeds like Kuphri, Alankar etc.
  2. The plant debris must be cleaned relative to field sanitation.
  3. To control the infection of late blight, one should employ a sprinkler irrigation technique that allows foliage to dry at regular intervals.
  4. The application of phosphorous acid to potatoes after harvest and before piling can minimise the occurrence of late blight.
  5. Harvesting of potatoes must be done in the dry season.
  6. The upper portion of the plant should be excised out before 15 days of harvesting.
  7. The earthing must be 10-15 cm deepened.
  8. There should be balanced used of nitrogen-fixing fertilisers.
  9. Seeds must be treated with 5% of ridomil and dust of 1kg/100kg of seeds.
  10. Seed storage is a primary factor to minimise the consequences of infection, by keeping the seeds at 3.5-4.4 degrees Celcius.
  11. The sources on inoculum like weeds and infected tubers (culls) must be eliminated.
  12. One can also use foliar fungicides to manage the disease.

Conclusion

Therefore, we can conclude that the late blight disease can cause outbreaks if not appropriately managed. As, the reproductive power of P. infestans is very high, which can form a huge number of sporangia from a single lesion that in turn can lead to other infection sites.

The disease cycle may continue either by the biflagellate zoospores or oospores, produced as a product of asexual or sexual reproduction of Phytophthora infestans. Late blight is a community disease, which might infect other fields or crops if persists longer.


Contents

The English word potato comes from Spanish patata (the name used in Spain). The Royal Spanish Academy says the Spanish word is a hybrid of the Taíno batata ('sweet potato') and the Quechua papa ('potato'). [11] [12] The name originally referred to the sweet potato although the two plants are not closely related. The 16th-century English herbalist John Gerard referred to sweet potatoes as common potatoes, and used the terms bastard potatoes and Virginia potatoes for the species we now call potato. [13] In many of the chronicles detailing agriculture and plants, no distinction is made between the two. [14] Potatoes are occasionally referred to as Irish potatoes or white potatoes in the United States, to distinguish them from sweet potatoes. [13]

The name spud for a potato comes from the digging of soil (or a hole) prior to the planting of potatoes. The word has an unknown origin and was originally (c. 1440 ) used as a term for a short knife or dagger, probably related to the Latin spad- a word root meaning "sword" compare Spanish espada, English "spade", and spadroon. It subsequently transferred over to a variety of digging tools. Around 1845, the name transferred to the tuber itself, the first record of this usage being in New Zealand English. [15] The origin of the word spud has erroneously been attributed to an 18th-century activist group dedicated to keeping the potato out of Britain, calling itself the Society for the Prevention of Unwholesome Diet. It was Mario Pei's 1949 The Story of Language that can be blamed for the word's false origin. Pei writes, "the potato, for its part, was in disrepute some centuries ago. Some Englishmen who did not fancy potatoes formed a Society for the Prevention of Unwholesome Diet. The initials of the main words in this title gave rise to spud." Like most other pre-20th century acronymic origins, this is false, and there is no evidence that a Society for the Prevention of Unwholesome Diet ever existed. [16] [12]


Melanotus Communis

No common name, Melanotus communis Gyllenhal, Elateridae, COLEOPTERA

DESCRIPTION

Adult &ndash This wireworm adult is a hard, slick, reddish-brown to black click beetle about 13 mm long.

Egg &ndash The white, glistening egg is oval to spherical in shape and 0.33 mm long.

Larva &ndash A wireworm larva has 3 pairs of short legs near its head. M. Communis has a pale yellow to reddish-brown body, a brown, flattened head, and a scalloped last abdominal segment. When fully grown, this wireworm ranges from 21 to 25 mm in length.

Pupa &ndash The white, soft-bodied pupa has no protective covering and is approximately the same size and shape as the adult.

Distribution &ndash This wireworm species can be found throughout the United States, but is particularly common in the mid-western and southeastern states. Damage tends to be prevalent in fields which follow sod or no-till corn.

Host Plants &ndash The wireworm, M. Communis, feeds on the roots of many grasses, including corn and many small grain crops. It may also attack the roots, seeds, and tubers of many flower and vegetable crops, especially potatoes and sweet potatoes. This species has been known to infest tobacco.

Damage &ndash This wireworm creates holes in potato and sweet potato roots similar to those caused by the tobacco and southern potato wireworms. However, due to the size of this species, the holes are noticeably larger and deeper than those of other species. Damaged roots and tubers are downgraded and discarded. M. Communis is the most damaging wireworm in the more northern sweet potato-growing areas.

Life History &ndash This wireworm species has a 6-year life cycle. In June of the first year, adults deposit eggs singly among the roots of grasses. First instar larvae emerge in July and begin feeding on roots. Larvae continue to develop throughout the summer and overwinter in the ground as second instars during the first year. Most of these immatures remain in the larval stage for 5 years although life cycles as short as 3 years have been reported. In late July or August of the 6th year, mature larvae construct oval cells 15 to 30 cm deep in the soil and pupate. M. communis adults emerge about 18 days later and feed on pollen before hibernating in protected areas. They become active and deposit eggs the following May or June.

Control consists of avoiding land previously in sod or out of production. The preplant use of fumigants for nematode control will also provide some control of this soil inhabitant. Traditional applications of a granular insecticide over the row in late July are thought to be of little value against this wireworm species.

Melanotus communis. A. Adult. B-C. Larva and tip of abdomen. D. Pupa.

Melanotus communis. A. Adult. B-C. Larva and tip of abdomen. D. Pupa.

Contents

The genus name Phytophthora comes from the Greek φυτό –(phyto), meaning : "plant" – plus the Greek φθορά (phthora), meaning : "decay, ruin, perish". The species name infestans is the present participle of the Latin verb infestare, meaning : "attacking, destroying", from which we get the word "to infest". The name Phytophthora infestans was coined in 1876 by the German mycologist Heinrich Anton de Bary (1831–1888). [5] [6]

The asexual life cycle of Phytophthora infestans is characterized by alternating phases of hyphal growth, sporulation, sporangia germination (either through zoospore release or direct germination, i.e. germ tube emergence from the sporangium), and the re-establishment of hyphal growth. [7] There is also a sexual cycle, which occurs when isolates of opposite mating type (A1 and A2) meet. Hormonal communication triggers the formation of the sexual spores, called oospores. [8] The different types of spores play major roles in the dissemination and survival of P. infestans. Sporangia are spread by wind or water and enable the movement of P. infestans between different host plants. The zoospores released from sporangia are biflagellated and chemotactic, allowing further movement of P. infestans on water films found on leaves or soils. Both sporangia and zoospores are short-lived, in contrast to oospores which can persist in a viable form for many years.

The color of potato sign is white. People can observe Phytophthora infestans produce sporangia and sporangiophores on the surface of potato stems and leaves. [9] These sporangia and sporangiophores always appear on the lower surface of the foliage. As for tuber blight, the white mycelium often shows on the tubers' surface. [10]

Under ideal conditions, the life cycle can be completed on potato or tomato foliage in about five days. [7] Sporangia develop on the leaves, spreading through the crop when temperatures are above 10 °C (50 °F) and humidity is over 75–80% for 2 days or more. Rain can wash spores into the soil where they infect young tubers, and the spores can also travel long distances on the wind. The early stages of blight are easily missed. Symptoms include the appearance of dark blotches on leaf tips and plant stems. White mold will appear under the leaves in humid conditions and the whole plant may quickly collapse. Infected tubers develop grey or dark patches that are reddish brown beneath the skin, and quickly decay to a foul-smelling mush caused by the infestation of secondary soft bacterial rots. Seemingly healthy tubers may rot later when in store.

P. infestans survives poorly in nature apart from its plant hosts. Under most conditions, the hyphae and asexual sporangia can survive for only brief periods in plant debris or soil, and are generally killed off during frosts or very warm weather. The exceptions involve oospores, and hyphae present within tubers. The persistence of viable pathogen within tubers, such as those that are left in the ground after the previous year's harvest or left in cull piles is a major problem in disease management. In particular, volunteer plants sprouting from infected tubers are thought to be a major source of inoculum at the start of a growing season. [11] This can have devastating effects by destroying entire crops.

P. infestans is diploid, with about 11–13 chromosomes, and in 2009 scientists completed the sequencing of its genome. The genome was found to be considerably larger (240 Mbp) than that of most other Phytophthora species whose genomes have been sequenced Phytophthora sojae has a 95 Mbp genome and Phytophthora ramorum had a 65 Mbp genome. About 18,000 genes were detected within the P. infestans genome. It also contained a diverse variety of transposons and many gene families encoding for effector proteins that are involved in causing pathogenicity. These proteins are split into two main groups depending on whether they are produced by the water mould in the symplast (inside plant cells) or in the apoplast (between plant cells). Proteins produced in the symplast included RXLR proteins, which contain an arginine-X-leucine-arginine (where X can be any amino acid) sequence at the amino terminus of the protein. Some RXLR proteins are avirulence proteins, meaning that they can be detected by the plant and lead to a hypersensitive response which restricts the growth of the pathogen. P. infestans was found to encode around 60% more of these proteins than most other Phytophthora species. Those found in the apoplast include hydrolytic enzymes such as proteases, lipases and glycosylases that act to degrade plant tissue, enzyme inhibitors to protect against host defence enzymes and necrotizing toxins. Overall the genome was found to have an extremely high repeat content (around 74%) and to have an unusual gene distribution in that some areas contain many genes whereas others contain very few. [1] [12]


Genetics of Morphological and Tuber Traits

6.3.3 Tuber shape

Tuber shape is a syndrome of many characters, which have contributed to a rich spectrum of cultivar names such as ‘Kidney’, having a strong degree of flatness, ‘Pink Fir Apple’ with a tuberosed form resembling a pinecone (due to extreme bulking of the tuber area between the eyes), ‘Asparges’, a very long tuber, ‘Banana’, ‘Long Pinkeye’ and ‘muizen’, an ovate form tapering at the apical end. For pictures, I refer to page 277 in the publication by Bradshaw and Mackay (1994) . More systematically, the tuber shape characters can be subdivided into the following components: (1) length/width ratio (I) describing the overall shape, (2) tapering of the heel-end and/or the rose-end, where oblong tuber shapes could be viewed as the other extreme of highly tapered tuber ends, and (3) straightness of the length axis. The older literature has been reviewed by De Jong and Burns (1993) and Bradshaw and Mackay (1994) .

Only for the overall tuber shape is the inheritance somewhat understood. The basic notion described in various older publications indicates that tuber shape is regulated by a single locus Ro, where round (Ro_) is dominant over long (roro). De Jong and Rowe (1972) confirmed linkage between loci involved in tuber shape and skin colour. Both loci indeed map close to TG63 on potato chromosome X ( van Eck et al., 1993b , 1994 Jacobs et al., 1995 ). Nevertheless, the genetic model described here does not satisfactorily explain the observation of tuber shapes ranging from round (I < 1.4) to oval (1.5 <I< 1.9) to long (I > 2.0). In the paper of 1993, De Jong and Burns could phenotypically identify all three possible genotypes (RoRo, Roro and roro) that were segregating in their genetic material. This suggests incomplete dominance at the Ro-locus. Nevertheless, tuber shape phenotypes are not confined to these three classes but display a continuous distribution. Continuously distributed traits are often interpreted as being controlled by polygenes, but in the case of tuber shape, the single gene hypothesis is maintained. At the Ro-locus, a series of multiple alleles can explain all intermediate shapes between round (going to flat) and long ( van Eck et al., 1994 ). At the tetraploid level, multiple alleles can make large numbers of allele combinations and intralocus allele interactions, which may explain the continuous range of tuber shape phenotypes. At the molecular level, the function of the Ro-locus is not understood, and once this gene has been cloned, further analysis of alleles and allele effects can be investigated.

Tuber shape has been studied in correlation with tissue composition ( Tai and Misener, 1994 ). They concluded a positive association between the length of the tuber and the narrowness of the pith, suggesting that long potatoes have a narrow pith and were inclined to have a smaller volume of pith. No clear association with other traits, such as specific gravity, was observed.


Breeding Genetics and Biotechnology

Starch Biosynthetic Enzymes

Starch in plant is synthesized in plastids such as the amyloplast and chloroplast. Starch biosynthetic enzymes contain transit peptides for transporting these enzymes from the cytosol to the amyloplast. At least four classes of enzymes catalyze the reactions of starch biosynthesis in plants, as follows ( Table 1 ): starch synthase (SS, EC 2.4.1.21) elongates α-1,4-glucan chains of starch ADP glucose pyrophosphorylase (AGPase, EC 2.7.7.27) produces the substrate ADP glucose (ADPG) for SS from glucose-1-phosphate (G1P) branching enzyme (BE, EC 2.4.1.18) forms the α-1,6 glucosidic bonds of amylopectin and debranching enzyme (DBE, EC 3.2.1.68) trims improper branches generated by BE. In addition to these enzymes, starch phosphorylase (PHO, EC 2.4.1.1) and disproportionating enzyme (EC 2.4.1.25) are also involved in starch biosynthesis.

Table 1 . Starch biosynthetic enzymes and their functions in rice

EnzymesIsozymesMutantsFunction of isozymes
SSSSIss1Elongation of DP 6–7 of A and B1 amylopectin chains by addition of 2–4 glucose residues
SSIIajaponica riceElongation of DP 6–12 of A and B1 amylopectin chains by addition of 6–12 glucose residues in the endosperm
SSIIbUnknown
SSIIcUnknown
SSIIIass3aElongation of B2–3 long chains connecting amylopectin clusters in the endosperm
SSIIIbss3bUnknown
SSIVaUnknown
SSIVbss4bOverlapped with the function of SSIIIa. Related to the morphology of starch granules?
SSVUnknown
GBSSIwaxy, gbss1Elongation of amylose and extra-long chains of amylopectin in the endosperm
GBSSIIElongation of amylose in the leaves?
BEBEIbe1Form branches in amorphous lamellae
BEIIabe2aForm branches in initiation stage?
BEIIbamylose-extender, be2bForm branches in crystalline lamellae in the endosperm
DBEISA1sugary-1, isa1Trimming of improper branches in crystalline lamellae of amylopectin
ISA2isa2Trimming of improper branches with ISA1
ISA3isa3Debranching of amylopectin in leaves
PULpulSlight compensation of the ISA1 function
PHOPHO1pho1Form primers in the initiation stage?
PHO2Unknown

SS, starch synthase GBSS, granule-bound starch synthase BE, branching enzyme DBE, debranching enzyme ISA, isoamylase PUL, pullulanase PHO, phosphorylase.

Many isozymes of these enzymes, encoded by different genes, exist in plants. The presence of so many isozymes indicates that plants have evolved the capacity to synthesize highly organized starch, because each isozyme has functional specificity for particular tissues, developmental stages, and substrates. The use of plant lines containing mutations in specific genes will elucidate the distinct roles and specificities of each isozyme and thus expand the understanding of starch biosynthesis. It is thought that starch biosynthetic isozymes form protein–protein complexes to synthesize starch efficiently. Complexes of several hundred kilodaltons (kDa) were detected after gel filtration of the stroma fraction from developing maize endosperm, although the molecular mass of a monomeric starch biosynthetic isozyme is 50–100 kDa. Moreover, immunoprecipitation experiments show that multiple isozymes have affinities for each other.


General Characteristics

'Goldrush' tubers have a brown skin with oblong to long shape and white flesh color (Figure 1). According to Florida rating codes for potato tuber characteristics (Table 1), the tubers have a good appearance with a moderate russet skin and intermediate to shallow eye depth. 'Goldrush' has demonstrated high yield potential under Florida production conditions (Tables 2 and 3). On average, marketable yield is 218 cwt/acre, approximately 6% below the commercial standard 'Red LaSoda', with 75% of the tubers produced found between classes A1 and A3 size distribution classes. It has a low to medium specific gravity of 1.061 (Table 2).


Introduction

Achieving the maximum crop yield at the lowest investment is an ultimate goal of farmers in their quest towards an economically efficient agricultural production. Early detection of problems associated with crop yield can greatly help in reducing the loss and reaching the targeted yield and profit. Potato is classified as being the fourth major staple around the globe, which is still quickly attaining importance [1]. The growing interest in potato, along with the diminishing agricultural lands, introduces the need for germplasm yield enhancement, better crop protection and much more efficient and productive management systems. Prediction of potato crop yield prior to the harvest period can be very useful in pre-harvest and marketing decision making. Many studies [2, 3] showed that traditional methods of crop yield estimation could lead to poor crop yield assessment and inaccurate crop area appraisal. In addition, these methods normally depend on rigorous field data collection of crop and yield, which is a costly and time-consuming process.

Remote sensing (RS) and global positioning system (GPS) technologies can be used to assess the temporal variation in crop dynamics, including crop yield and its spatial variability [4]. Visible (blue, green and red) and near infrared (NIR) portions of the electromagnetic spectrum have already proven their effectiveness in accessing information on crop type, crop health, soil moisture, nitrogen stress and crop yield [5–13]. Advancement in RS techniques enhanced the use of multispectral images as an effective tool in determining and monitoring vegetation conditions, crop stress and crop yield prediction. Liu and Kogan [14] revealed that remote sensing data offered exceptional spatial and temporal land surface characteristics, including the environmental impacts on crop growth. Numerous studies have reported that there could be a good correlation between the vegetation indices provided by the RS techniques and the crop yield and biomass [14–17]. A crop yield research that is conducted at a regional scale, which employs coarse or low-resolution satellite images, can provide a broader information on the crop canopy conditions and crop yield estimates. Hence, decisions in the quantitative export and import of the product within the region could be made in assured way.

Prediction of crop yields is typically associated with certain agronomic variables (density, vigor, maturity and disease), which can be used as yield indicators. Remote sensing offers a close diagnosis of plant health however, the spectral reflectance of the crop is dependent on phenology, stage type and crop health. Several studies [4, 6, 18–22] have focused on crop growth analysis using normalized difference vegetation index (NDVI) to enhance precision agriculture. Research in plant life monitoring has proven that NDVI is associated with the leaf area index (LAI) and the photosynthetic activity of crops. The NDVI is an indirect way of measuring the primary productivity through its quasi-straight line relation using the Fraction of Absorbed Photosynthetically Active Radiation (FAPAR) [23] and [24]. Also, Baez-Gonzalez [6] used Landsat ETM (enhanced thematic mapper) data with an NDVI model to estimate corn yield, where a prediction error of 9.2% in the yield was determined. Yang [25] used the United States Department of Agriculture (USDA) EPIC model to predict yield, where the difference between recorded and predicted yield was less than 10%. Baez-Gonzalez [18] modeled a corn yield with NDVI generated from NOAA Advanced High-Resolution Radiometer (AVHRR) images. A study by Gopalapillai and Tian [19] reported correlation coefficient (r) values varying from 0.13 to 0.98 for predicting corn yield from nine different fields using a span of two-year datasets. They used aerial pictures of the corn plots and calculated NDVI to predict yield, where the average correlation coefficient (r) between the NDVI and the yield over all the nine fields was determined at 0.54. On the other hand, soil adjusted vegetation index (SAVI) was used in some studies as it showed a tendency to minimize soil brightness, a phenomenon which has been addressed by Miura [26] and Lamb [27]. Jayanthi [28] carried out research on yield estimation of potato integrating the SAVI from high resolution airborne multispectral imagery and developed various yield models. Huete [29] introduced a soil calibration element in the NDVI equation to take into account the very first order optical interactions between soil and vegetation. Bala and Islam [30] used TERRA MODIS images to estimate a potato yield, where a prediction error of 15% was determined using ground truth data collected from 50 fields.

In addition to providing a decision support tool and revenue expectation, the predicted yield maps can be used as spatial databases for the implementation of variable rate technology (VRT) systems to achieve a precise application of field-level inputs in order to optimize production across the entire field. Therefore, this study was designed to provide a means of early prediction of potato yield (i.e. prior to the harvest period) using multispectral satellite remote sensing on a field scale. However, the specific objectives of this study were (i) to obtain an empirical equation for the early prediction of potato yield using multispectral images in conjunction with field collected potato yields, (ii) to determine the suitable growth stage for early prediction of potato yield, and (iii) to classify the obtained yield maps into distinct zones for the implementation of precision agriculture activities.