eChapters

Potato has special seed production problems as the quality characteristics of seed potatoes are influenced by a number of factors and important amongst them are the diseases and pests namely, viruses, fungi, bacteria and nematodes. Once the seed tuber is infected the pathogens, specially viruses, permeate through the plant system. The plant growth, therefore declines and the yield reduces progressively. It is therefore, important that seed stocks should not only be genetically pure but also should be in right physiological condition and disease free at the time of planting. Seed production technology developed for seed potato production, thus aims at producing disease free, genetically pure seed. There are now two independent channels of seed production for hills and plains.

Hill seed : The seed produced in hills (2500 metres above sea level) at suitable locations is called ‘Hill Seed’.

Plain seed : The seed produced in plains at suitable locations is called ‘plain seed’. Northern plains have emerged as an important source of potato seed production. The low aphid, plains seed is in right physiological condition at the planting time and yields higher than the traditional hill grown seed.

Once healthy seed potatoes are introduced into the system of growing them during low Aphid period accompanied by a systematic insecticide application, roguing and removal of haulms before the aphids attain critical number and the re growth is checked, the health standards for the seed crop could be maintained for a number of generations. This system of seed potato production has been designated as ‘Seed Plot Technique’.

INTRODUCTION

Potato (Solanum tuberosum L.) is 3^rd most important noncereal food crop in the world, after rice and wheat, and popularly known as ‘the king of vegetables’. Potatoes are considered as a nonfattening, nutritious and wholesome food, which supply important nutrients to the human diet. Tubers contain significant concentrations of vitamin C and essential amino acids. Potatoes can be consumed in many ways, including baking, boiling, roasting, frying, steaming, and microwaving. It is integral part of food and traditional cousins and likely to find more importance in the dietary habit. Potatoes are either consumed directly or they are processed to give products such as chips and French fries, mashed and canned potatoes. Besides being important in human diet, potatoes are also used as animal feed and as raw material for starch and alcohol production. Potato was an occasional dish of the affluent class at the time of independence but now it is the most abundantly consumed horticulture based food by the poorest of the poor in the country. At present about 68% are utilized for table purpose, 7.5% for processing; 8.5% for seed and remaining 16% produce goes waste due to pre and postharvest handling.

1. Early Blight
Diagnostic Symptoms
• Brown-black necrotic spot-angular, oval shape characterized by concentric rings .
• The concentric ring produce a target board effect, the most characteristic symptom of the disease.
• Several spot coalesce & spread all over the leaf.
• In severe attacks leaves shrivel and fall down.
• Infection and rotting of tubers has also been reported (Fig.1).
Etiology
Scientific Classification
Kingdom : Fungi
Phylum : Ascomycota

Introduction

At the time of inception of CPRI, in the year 1949, India used to produce 1.54 million tonnes potatoes from 0.234 million ha area at an average productivity level of 6.58 tonne/ ha. As per the first advance estimate of the NHB, the potato production in India during 2018-19 was 52.5 million tonnes from 2.18 million ha area at 24 tonnes/ ha productivity. The potato production, area and productivity increased over 7 decades by 34, 9.3 and 3.7 times, respectively. ICAR-CPRI has been adequately recognised by the nation on several occasions for this stupendous contribution. However, potato in India still has to transform from simply a vegetable supplement to serious food security option. Ability of potato to produce highest nutrition and dry matter on per unit area and time basis, among major food crops, made FAO to declare it the crop to address future global food security and poverty alleviation during 2008. Rising number of working couples, rapid rate of urbanization, enhanced tendency of eating out of home, higher disposable income levels of people and important place of potato in fast food items, create an ideal situation for expansion of potato consumption in the near and distant future.

A perusal of various R&D efforts and outcomes in the field of agriculture in general and, more specifically the potato, reveals that “Business as Usual” scenario would not hold much longer. We have to anticipate and get ready to tackle much more complex and diverse future challenges in our respective fields. As the time lag between research and development efforts and the final application/ adoption of the output may stretch over decades, a long term vision and blueprint of action plan is highly important. This chapter attempts to envisage long term state of affairs of potato industry in India and formulate a strategy to fulfil national needs through a well-documented plan to tackle anticipated challenges.

INTRODUCTION

Potato is an important horticultural food crop which has the potential to meet food demand of the fast growing human population across the world, including India. This is going to be the future food crop for the millions especially in the third world countries. However, this crop is highly prone to wide range of diseases and pests that are considered to be the main bottle neck in potato production across the globe. Amongst the biotic stresses, late blight caused by oomycete Phytophthora infestans (Mont.) de Bary has historically been an important disease of potatoes and tomatoes worldwide. In the mid 1800, late blight caused widespread crop failures throughout Northern Europe including Ireland where it was responsible for the Irish famine. Since then, it has spread far and wide and now occurs wherever potatoes are grown. Losses due to P. infestans have been estimated to € 12 billion per annum of which the losses in developing countries have been estimated around € 10 billion per annum (Haverkort et al., 2009). In India, average annual losses to the tune of 15% have been estimated which amounts to 7.95 million tons of potatoes (Current production is 53 MT). Disease appears every year in epiphytotic form in hilly regions whereas in the plains, although it usually appears every year but its intensity is low (traces to 25%). It is only in few years that it assumes epiphytotic form leading to crop losses to the tune of 40%. Recently, late blight has become a serious problem in kharif grown potatoes and tomatoes in Karnataka state (Sharma et al., 2015). Phytophthora infestans is considered as re-emerging pathogen due to regular emergence of its novel strains with increased virulence and its appearance in new locations with surprising intensity. Management of this devastating pathogen is challenged by its remarkable speed of adaptation to control strategies such as genetically resistant cultivars.

INTRODUCTION

Potato is a highly versatile crop grown in varying environmental conditions viz. plains, hills and plateau in India. It is grown under short days (SD) in the plains in autumn season and under long days (LD) during summers in hills. Therefore, the pattern of growth, duration of crop as well as the yield varies according to the environment. Besides, the potato cultivars differ from each other in relation to their morphological characters, response to the environmental factors and finally in yield and the dry matter accumulation. The biochemical reasons for such variations are not clear, but it seems that genetically determined differences in the synthesis of growth regulators such as auxins, cytokinins, gibberellic acid (GA) and abscissic acid (ABA) play an important role and their proportion at different growth stages affect the growth and development and thus, the yield of the cultivar (Minhas and Singh, 2003).The present chapter deals with the physiologicalfactors, which determine the growth, development and yield of potato crop.

INTRODUCTION

Potato production in India has shown a steady increase in the past, presently making the country second largest potato producer in the world. As per the latest available data, during 2018-19, approximately 52.5 million metric tons of potatoes have been produced (NHB, 2019). Increase in production, often resulting in gluts at harvest, has led to several post-harvest problems like storage and proper utilization of the produce. About 90% of the potato crop in the countryis harvested during January-February in the Indo-Gangetic plains comprising the states of Punjab, Haryana, UP, Bihar, West Bengal, MP and Gujarat where the harvest is followed by rising temperatures of hot and dry summer, and further by warm and humid rainy season. Since potato tubers contain about 80% water, under such circumstances, a semi-perishable commodity like potato, cannot be stored for more than 3-4 months without refrigeration because of very high losses due to shrinkage, sprouting and attack by microorganisms.

Therefore, potatoes are mostly stored in refrigerated cold stores maintained between 2-4^oC and 90-95% relative humidity (RH). Low temperature storage has advantages of natural control of sprout growth, low evaporative losses and minimum risk of diseases and pests. These conditions are ideal for storage of seed potato but these cause cold-induced sweetening leading to excessive accumulation of sugars in most of the potato cultivars making them unfit for processing due to browning in chips. Also, such tubers are less preferred for consumption because of sweet taste. Hence, potatoes meant for processing are either stored under non-refrigerated conditions for short term or stored at 10-12^oC with the use of some sprout suppressant like CIPC (isopropyl N-(3chlorophenyl) carbamate) to minimize the accumulation of reducing sugars. The chips produced from such tubers are light in colour.

Potato processing on the other hand is essential to sustain the increasing potato production in the country and to provide proper remuneration to the cultivators. Potatoes can be processed into a variety of products. Potato chips, French fries and dehydrated chips are the most popular processed potato products in the organized and unorganized sectors. The present chapter deals with postharvest management of potatoes in terms of dormancy and sprouting issues and storage technologies for seed, table and processing potatoes. Besides, areas suitable for growing processing potatoes in the country, potato processing scenario in the organized and unorganized sectors are also discussed.

INTRODUCTION

India is the second largest producer of potato in the world contributing about 12.52%of production from 11.29 % area under potato with an average yield of 22.31 t/ha. Potato is grown in almost allthe states in India under diverse agroclimatic conditions. About 90% of the total potato area is located in the subtropical plains, 6% in the hills and 4% in the plateau region of the peninsular India. Indo-Gangetic plains account for about 76% of the potato area and about 87% of the potato production in the country. Availabilityof assured qualityseed is the most important production constraint in all the potato growing regions of the country.

Seed is the basic vital input in agriculture and its timely availability in adequate quantity as per demand decides the strength growth of agricultural economy in the country. Seed has played a very important role in India’s green revolution and shallcontinue to be the importantcomponent in the days to come. There is a saying “as you sow, so shall you reap”, which traditionally relates to the quality of seed determining the production, has been the wisdom of our forefathers. The traditional farmers’ practices are to save their own seeds generally selected from healthy plants from fields which are freefrom diseases pests, harvest them separately, clean, cure and then store in containers and inspect regularly for any kind of damage; or they get quality seed from other seed producing farmers onbarter basis, indicating thereby the importance of seed in their production system.

I. FILL UPS

1. The potato is made up of _____ and _____.
2. Potato is a _____ pollinated crop
3. Potato fruit is called as_____.
4. An example of stem tuber is a _____.

This protocol is designed for potato stem internodes on ZIG medium, but might work for leaf pieces as well.

Plant Material

Cut stem internode explants from 5-6-week-old in vitro plants (or leaf explants from 3-4-week-old in vitro plants) grown on 15 ml PROP in 25 x 150 mm test tubes.

Day 1

Streak out desired Agrobacterium strain on YEP + antibiotic to obtain a single colony. Grow at 28 C for 2 days. Alternatively, skip this step and use frozen stock for next step.

Day 3

Use a single Agrobacterium colony to inoculate 20 ml YEP + antibiotic in 250-ml flask. Grow overnight at 28 C with vigorous shaking (~200 rpm). Some Agrobacterium strains require an additional day to reach sufficient density.

INTRODUCTION

Potato (Solanum tuberosum L.) is the most importantnon-grain food crop of the world and is central to global food security, offeringhigher yields in calories per acre thanany grain.More than 2 billion people worldwide are estimated to be dependent on potato for food, feed or income. Global potato breeding concentrates on the objectives of increasing the yields through resistance to various biotic and abiotic stresses along with improving quality traits but the cultivated potato is an auto-tetraploid (2n=4x=48), clonally propagated, highly heterozygous, and suffers acute inbreeding depression. All these characters complicate genetics/genomic studies as well as breeding efforts to improve important traits such as disease/pest resistance, processing quality and nutritive value.This has lead to the need of high quality, well annotated genome sequence of potato along with high resolution mapsfor aiding the identification of allelic variants for important agronomic traits in potato. Multiple linkage maps have beenconstructedfor potato usingvarious molecularmarkers like RFLPs, AFLPs and SSRs in an effort to develop markers for marker assisted breeding and facilitate map based cloning. These earlierefforts got unequivocal boost when an internationalcollaborationof13countriesviz.Argentina, Brazil,China, Chile, India, Ireland, The Netherlands,New Zealand, Peru, Poland, Russia, the United Kingdom and the United States came together to form the Potato Genome Sequencing Consortium (PGSC) with aim to decipher the potato genome (Xu et al., 2011). The potato genome sequence has provided a major boost to gaining a better understanding of potato trait biology, underpinning future breeding efforts. This would greatly help in enhancing the breeding techniques by implementing the genome assisted methods for imparting the greatertolerance to various biotic and abiotic stressesand ultimately increasing the yields. The knowledge of the complete genome sequence is an invaluable resource for the identificationof genes and variant/novel alleles of genes for everytrait ofinterest to potato breeders. This is very much required for feeding the ever burgeoning global population.

Introduction Potato, scientifically known as Solanum tuberosum, is a starchy tuberous crop that belongs to the nightshade family, Solanaceae. It is one of the most widely consumed and important food crops worldwide. Potatoes are native to the Andes region of South America and have been cultivated for thousands of years. They have since become a staple food in many countries and have significant cultural and economic importance. Potatoes are known for their versatility, as they can be prepared and cooked in various ways. They are typically harvested from underground stems called tubers, which come in a variety of shapes, sizes, and colours. The most common varieties have brown or yellowish skin and white, yellow, or creamy flesh. However, there are also red, purple, and even blueskinned potatoes available. The cultivation of potatoes is widespread, with major potato-producing countries including China, India, Russia, the United States, and Germany. Potatoes are adaptable to different climates and can be grown in diverse environments. They are an important crop for food security and economic stability in many regions. Beyond their culinary significance, potatoes have also contributed to scientific advancements.

Aphids: Myzus persicae, Lipaphis erysimi and Brevicoryne brassicae Aphididae
 
Aphids suck the sap from potato foliage, causing wrinkling, cupping and downward curling of young leaves. The older leaves will become yellow, wilt and fall off.  They also excrete honeydew on which sooty mould develops covering affected parts with a thin superficial black coating that hinders photosynthetic activity of leaves resulting in stunted growth of plants. In addition, they also act as vectors, for transmitting potato leaf roll virus. Major damage by M.persicae and A. gossypii is through transmission of potato leaf roll virus.

Potato is fourth major food crop after rice, wheat and maize in the world. It produces the highest dry matter, well balanced protein and more calories/ unit area and time. Unlike other food crops, potato tubers contain vitamin-C (17 mg/100 g). It provides carbohydrates, minerals, fibre and a number of vitamin-B groups. Potato protein is comparable to that of milk and egg. Unlike European countries, in tropics and sub-tropics, the crop is of short duration and fits well in intensive cropping system. It can be grown in a wide range of climatic and soil conditions and tubers are available throughout the year. Tubers can be left un-harvested in the soil for some time and are also suitable for long distance transport and storage. Several products like chips, flakes, French-fries, finger chips, granule, disc, cubes and flour are made out of potato tubers

Origin and distribution

Potato is a native of tropical South America. Traditionally, it was adapted as a commercial food crop in temperate climate under long day conditions, mainly in Europe. It was introduced to India in 16^th or 17^th Century by Portuguese or the British. 

If there is scarcity of food, potato can come to the rescue because of its virtue of high yielding (40-50 t/ha) and is a staple food. It produces more calories per unit area and per unit time than any other major food crops. Potato which is the staple food of Europeans and Americans belong to the highlands of Andean mountainous regions of Peru and Bolivia where it has been cultivated since 6000 years.
 
Origin: Peru, Bolivia. Many wild species occur at Mexico and Central America. Potato was introduced to Europe in 16th century by Spaniards (Salaman, 1966) and in early 17th century to India most probably by Portuguese. There are some suggestions based on linguistic and botanical evidences that potato might have been introduced in India directly from South America across the Pacific Ocean. Earlier potatoes were grown in hilly areas of North and South since British settlers brought the varieties continuously from UK and these were bred for long day temperate conditions of Europe. But in India potatoes are grown in short day-subtropical plains. The seed stocks used to degenerate due to accumulation of viruses and loose their yield potentiality. Seed potatoes were mainly imported from Europe i.e. U.K., Italy and Netherlands and Burma till the beginning of Second World War and the imports gradually reduced.

Potato is fourth major food crop after rice, wheat and maize in the world.  It produces the highest dry matter, well balanced protein and more calories/unit area and time.  Unlike other food crops, potato tubers contain vitamin-c (17 mg/100 g). It provides carbohydrates, minerals, fibre and a number of vitamin-B groups.  Potato protein is comparable to that of milk and egg.  Unlike European countries, in tropics and sub-tropics, the crop is of short duration and fits well in intensive cropping system.  It can be grown in a wide range of climatic and soil conditions and tubers are available throughout the year. Tubers can be left un-harvested in the soil for some time and are also suitable for long distance transport and storage. Several products like chips, flakes, French-fries, finger chips, granule, disc, cubes and flour are made out of potato tubers.

Disease appears later part of the crop season mostly during blossoming period. The first sign of the disease is the appearance of small brown patches on the leaves mostly on basal leaves which starts from tip or margin of leaves and spread downwards or inward directions.

Potato, Solanum tuberosum L. under the family Solanaceae (Chromosome No. 2n = 4x = 48) is the world’s most important vegetable crop and the fourth most important food crop after rice, wheat and maize. They contain a wealth of health benefits that make them essential as a staple dietary item for much of the world’s population. It is valuable both as a fresh product and as a processed product, and the current trend is for rapid growth in processed forms, mainly chips and French fries. It is now grown in nearly 150 countries. It is extensively cultivated in China, Russia, Ukarine, Poland, Ireland, Great Britain, Germany, Netherlands, France, Spain, South America, India and USA.
Origin, domestication and adaptation in India
Potato is a native of tropical South American region where it grows wild in nature and presents the widest diversity of forms like, tuber shape, size, colour, taste, etc. Cultivated diploid potatoes are believed to have originated in the high plateau region of Peru and Bolivia in South America, more specifically the Lake Titicaca basin in the Peru-Bolivian region (Simmonds, 1976).

ABSTRACT

This article is an attempt to describe potential agroforestry systems for mid hills zone of Himalayas. The existing traditional land use systems with separate allocation to agriculture and forest are inadequate not only to fill gaps between demand and supply for food, fuel, fodder and timber but also to check land degradation and soil erosion. The adoption of common agroforestry systems, namely agrisilviculture, agrihorticulture, agrisilvihorticulture, agrihortisilviculture, silvimedicinal, silvipastoral and hortipastoral along with appropriate management practices shall be suitable and viable option for checking soil erosion, improving productivity and economic status of the farming community. The functional components of agroforestry systems, however, differ greatly in size, texture and nature depending on the necessity of rural population. The fuel, fodder, timber and fruit trees dominate in the hilly regions, whereas commercial species like poplar, eucalyptus, shisham, etc constitute the major functional component in lower Shivaliks. Farming communities successfully grow food crops like wheat, maize, soybean, pea, black gram; vegetable crops like tomato, cabbage, capsicum; tuber crops and medicinal crops with multipurpose woody perennials. The findings indicate that agricultural crops can be integrated with woody perennials without any adverse impact on growth, production or physiological status of food crops, except when growing immediately beneath tree canopies. Our experience is that planting timber, fuel-fodder or fruit tree species in combination with agricultural crops and medicinal and aromatic herb species pave the way for diversified products and better economic returns to the farmers. Multipurpose tree species outside the forest have played very important role in catering to the day to day requirements of the rural population, beside environmental conservation. Different farming systems consisting crops + trees have yielded encouraging results and have not only helped diversification but enhanced productivity of land per unit area. Intercropping medicinal and aromatic herb species, especially with fruit and commercial timber further makes agroforestry more profitable.

Introduction 
The fundamental goal of agriculture is to harness the earth‘s resources to produce food, feed, fiber, and fuel to sustain a growing global population. At the heart of this endeavor lies the concept of crop production, a complex interplay of genetic potential, environmental factors, and human management. This chapter, Potential and Achievable Crop Production, delves into the crucial distinction between what a crop can produce under ideal circumstances and what it actually produces in the farmer‘s field. Understanding this dichotomy is paramount for addressing global food security challenges, optimizing resource utilization, and developing sustainable agricultural practices. We will begin by exploring the theoretical maximum yield, often termed "potential production," which represents the inherent capacity of a crop variety to produce biomass and yield when all limiting factors are eliminated. This potential is primarily dictated by a crop‘s genetic makeup and the prevailing climatic conditions, such as solar radiation, temperature, and carbon dioxide concentration. Subsequently, we will shift our focus to achievable production, the real-world yield obtained by farmers. This actual yield invariably falls short of the potential due to a myriad of biotic (pests, diseases, weeds), abiotic (water scarcity, nutrient deficiencies, extreme temperatures, poor soil health), and socio-economic (lack of access to inputs, knowledge, or markets) constraints. The disparity between potential and achievable yield, known as the "yield gap," represents a significant opportunity for enhancing agricultural output without necessarily expanding cultivated land. By meticulously examining the factors that contribute to this gap, we can identify targeted interventions and innovative strategies to bridge it, thereby moving closer to realizing the full productive capacity of our agricultural systems. This chapter will therefore provide a comprehensive framework for understanding the science behind crop yields and the practical approaches required to optimize them for a more food-secure future.