eChapters

Ethylene is a primary plant hormone involved in the senescence of plant tissues including flowers and leaves. In carnation flowers, inhibition of the synthesis or action of ethylene delays the onset of senescence symptoms and lengthens the vase life of flowers. Leaves of cut chrysanthemum of some cultivars frequently become yellow, sometimes prior to the onset of flower senescence, in response to exogenous ethylene. Generation of transgenic plants with suppressed production or action of ethylene is an excellent way to lengthen the longevity of these ornamental plants. This paper reviews our studies on generation and characterization of carnations with reduced ethylene production and chrysanthemum with reduced sensitivity to ethylene.

Plant breeding or crop plant improvement is one of the oldest accomplishments of man. It began when he domesticated plants by growing them under controlled conditions and selecting those types that suited to his food requirements, about 10,000 years ago. As settlements improved, men could find time to innovate agricultural practices and to have better selections. Thus, domestication of plants and animals marked one of the most important phases in man’s progress from a nomadic and highly individualistic life to the organized and cooperative society. All our food crops as we know them now are the direct results of this primitive agriculture. This early phase of plant breeding was haphazard and slow based on selection of desirable types from the availability variability and it largely remained an art and not a science until Mendel’s laws were rediscovered in 1900 and applied to plant breeding at the beginning of 19^th century. 

1. INTRODUCTION

The past hundred and fifty years of this millennium have witnessed an unbelievable pace of scientific and technological development. Modern science has attempted to a great extent and succeeded in realizing the dreams and fantasies of philosophers and scientists of the previous centuries. Plant genetic engineering via., nucleus is a mature technology that has been used productively for research and commercial applications. However, plants have an unassuming second genome inside the tiny organelles called as plastids. Although this small circular DNA carries a fewer genes than its nuclear counterpart, researchers say its potential for genetic engineering far outstrips its size. The ability to introduce foreign genes at specific locations on a chloroplast has been acquired very recently. It is expected that certain limitations of nuclear genome transformation methods in terms of protein expression and environmental safety can be overcome by site-specific introduction of genes into plastids. Thus the plastid engineering forms a viable alternative serving as another milestone in the field of plant biotechnology.

Transportation and distribution of fruits and vegetables are important stages   of post-harvest loss. In India,  transportation of perishable commodities is in the most precarious stage. For local market, the produce is brought either by bullock cart or tractor trollies. The long distance transportation is mainly by rails and trucks, which is very costly. The basic reason for preference to road transportation is that it takes short transit period.

India is a huge importer of crude oil and spends about Rs. 1,200 billion of foreign exchange every year to meet 75% of its oil needs (Anand, 2006). This has affected its balance of payment adversely, especially after the unprecedented rise incrude oil prices. Being an agricultural country endowed with varied climates, nutrient-rich soil and ability to grow many different crops, India offers a great promise as a producer of surplus raw material for biodiesel and bioethanol production. India’s biofuel production currently accounts for only 1 percent of global production (Shinoj et al., 2012). Although all oils can be used, edible oils as a source for biodiesel production have to be ruled out because they are required for cooking and food purposes. Therefore, non-edible oils are the premier raw material for biodiesel production in India. Seeds rich in these oils are mostly produced by perennial species. Hence these trees are referred to as tree-borne oilseed species (TBOS) and they produce TBOs (Aurora and Kumar, 2015). TBOs are cultivated/grown in the country under different agro-climatic conditions in a scattered form in forest and non-forest areas as well as in waste land/deserts/hilly areas. The country has enormous potential of oilseeds of tree origin like mahua (Madhuca indica),neem (Azadirachta indica), simarouba (Simarouba glauca), karanja (Pongamia pinnata), ratanjyot (Jatropha curcas), jojoba (Simmondsia chinesis), cheura (Diploknema butyracea), kokum (Garcinia indica),wild apricot (Prunus armeniaca), wild walnut (Aleurites molucana), kusum (Schleichera oleosa), tung (Vernicia fordii), etc. The best characteristic is that it can be grown and established in the wasteland and have varied agro-climatic conditions. (Aurora and Kumar, 2015)

Tree tomato belongs to the family solanaceae, genus Cyphomandra and species betacea. The Cyphomandra genus is made up of about 30 species. Shaw (1996) has reported that Cyphomandra genus consists of 35 species confined to the New World tropics. They were earlier described under the genus Solanum. They can be separated from Solanum  by several characters, the most important being anther characters. In Cyphomandra in the anther the connective is thickened and expanded dorsally. As a result, it is clearly differentiated from the anther thecae, which is thin walled and papillose.

Economically important plant in this genus is Cyphomandra betacea. Other important related species are Cyphomandra casana (Casana), C. craccifolia (Mountain tomato) and C. fragrans (Guava tamarillo). It has got distant affinity with Lycopersicon esculentum (Tomato), Physalis ixocarpa (Tomatillo), P. peruviana (Cape gooseberry), Solanum muricatum (Pepino Dulce) and S. sessiliflorum (Cocona).

Tree-borne vegetables spring out from woody perennial plants. There are too many trees in nature across the globe which offer edible fruits, a few of them are exploited for vegetable purpose. Of course, in popular parlance, vegetable gives the connotation of the product of herbaceous crop, but there are vegetables which are the product of woody perennials. In the present agri-horti-scenario, where diversity in product range is the most sought after aspect, attempts are underway to popularize culture of such vegetables which have not yet found commercial momentum at the grower’s field. Tree-borne vegetables are one such group which needs proper popularization to really help to percolate their farming. These vegetables being vested with woody nature, tap root system, bark covering and stress tolerance mechanism are worth exploitation under diverse farming systems prevalent across the country. Further many tree-borne vegetables are rich in nutrients also and as such add to their plus identity.

Trees

A trees is a woody perennial plant with clear stem or trunk. Trees trend to be long leaved living up to several 100 year.

TREE- logical meaning of each letter

T - Temperature and micro-climate moderation.

R - Removal of air pollutant.

E- Erosion control.

E - Energy conservation.

Introduction

Production system under arid and semi-arid region faces several biophysical constraints (high solar radiation, low and erratic rainfall, high wind velocity, poor soil conditions, etc.). Availability of irrigation water and irrigation potential in these regions are meager. Nutrition, food security and sufficient livelihood options based on agriculture are the major challenges of the people living in these regions. Sustainable productivity in these regions cannot be achieved by monoculture of either seasonal or forage crops, and thus hinges the need for diversifying the cropping pattern through fruit based cropping system which has good potential particularly in the arid and semi-arid regions. Because hunger and malnutrition are often linked to poverty, providing economic opportunities through horticultural production not only helps family incomes, but also addresses food security and nutrition. Thus, cropping system approach for agricultural production has greater significance in these regions.

1. Introduction

Agriculture is prime source of living for rural people world wide effective in raising incomes among the poorest compared to other sectors. In Indian economy horticulture has been recognized as one of the most potential agriculture endeavours in terms of exponential growth. The Horticultural crops viz., fruits counting nuts, vegetables with potato, ornamental plants plus cut flowers, spices, plantation crops and medicinal and fragrant plants has developed a prime promoter for monetary growth in numerous of the states in the nation and it pays 30.4% to GDP of agriculture (ICAR website).

Major cucurbits grown in India are cucumber, watermelon, muskmelon, ash gourd, pumpkin and squashes, snake gourd, ridge gourd, smooth gourd, bottle gourd, round gourd, bitter gourd, pointed gourd, ivy gourd,pointed gourd and oriental pickling melon. After independence,a lot of breeding work were done in these crops at many research institutes in the country which  resulted in  release of several high yielding/disease resistant varieties/hybrids.

Being warm season crops, cucurbits are tropical in origin, mostly in Africa, Tropical America and Asia. Flowering in cucurbits normally start in 40 to 45 days after sowing depending on weather conditions. Sequence of flowering follows a set pattern, namely the first 4 to 6 flowering nodes would bear staminate flowers and later pistillate flowers appear. Many sex forms are seen in cucurbits viz., monoecious, dioecious, gynoecious,trimonoecious, gynomonoecious and andromonoecious. Sex modification is also possible in cucurbits by exogenous application of plant growth regulators. GA₃ and AgNO₃ are used for inducing male flowers in gynoecious lines. Conversely,ethrel and TIBA  are used to promote greater number of female flowers. This kind of sex modification is more useful and practicable in  cucumber and bottle gourd where continuous and simultaneous flowering, fruit set and fruit picking take place.

Mango occupies a pre-eminent place amongst the fruit crops grown in India and is acknowledged as the ‘King of Fruits’. Mango is the pride of the garden and one of the choicest fruits known to mankind. Mango possesses unique nutritional and medicinal qualities apart from being a rich source of vitamins A and C. Young and unripe fruits are utilized for culinary purposes, preparing pickles, chutneys because of their acidic taste as well as for extraction of tannin and other astringent products. Ripe fruits are a delicacy for the table and are utilized in preparing squash, juices, nectar, jam, cereal flakes, custard powder, baby food, mango leather and toffee. Canned mango slices and pulp are indeed very popular. The inside kernel of the stone being rich in carbohydrates, calcium and fat, can be used as a source of food for certain industrial purposes.

Tropical plum (Spondias mombin) also known as yellow mombin, hog plum, and java plum, is a deciduous fruit species widely spread in the tropics. This species is evaluated for its fruit as an unconventional source of vitamins A and C, which are used for making juices, ice creams and jellies. This plant also has medical importance.
 
It is a graceful tree of the family Anacardiaceae, a native of tropical America. It was introduced into India for edible fruit and also to serve as fencing. The fruit flesh (48% on  weight of fruit) contains: total solids 11.47%, protein 1.38%, fat 0.57%, acids (astartaric) 1.50%, reducing sugars 9.41%, sucrose nil, fibre 1.17%, and mineral matter 0.66%. The seeds are eaten when tender. The fruit is a good source of minerals and vitamin B1 and C.

Tomato, the ‘Apple of Love’ or ‘Golden Apple’ is one of the most popular, widely grown and highly praised vegetable in the world. In India, commonly referred as ‘Poor Man’s Orange’, has wider coverage in comparison to other vegetables. Tomato universally treated as ‘Protective Food’, is eaten raw or cooked or in processed form (soup, juice, ketchup, puree, paste and powder, green tomato - pickles and preserves) or it supplies vitamin C and adds variety of colours and flavours to food. It is a very good source of income to small and marginal farmers and contributes to nutrition of consumers. Tomato seed contains 24% oil used as salad oil and in manufacture of margarine. By virtue of its many attributes, it is considered as a favourite crop for research in physiology and cytogenetics, all over the world. Tomato is also rich in medicinal value. The pulp and juice are digestible, mild aperient, a promoter of gastric secretion and blood purifier. Tomato, a primary source of lycopene, showed significant association with low prostate cancer risk and cancers of digestive tract. It is one of the best vegetables which keeps our stomach and intestine in good condition. Tomato juice has become an exceedingly popular appetizer and beverage.

INTRODUCTION

Potato is a vegetatively propagated crop mainly through tubers. Seed is the costliest input, which constitutes nearly half of the production cost. Due to the high cost of seed, seed replacement rate is low, which results in build up of various tuberborne diseases.To maintain high tuber yield, multiplication is done through “Seed Plot Technique” (SPT), which involves seed production in low aphid pressure period to minimize transmission of viruses and also adopt a set of cultural practices aimed at minimizing disease spread. The production of healthy seed tubers through SPT is expensive and the low rate of tuber multiplication (normally 68 times) provides only a limited quantity of quality tubers. Further, the low aphid areas suitable for producing healthy seed in the country lie in the northern plains and high hills (> 1800 m above mean sea level). Changing climate scenario is likely to shrink the window for potato cultivation and increase pathogen/vector attacks across the country thereby seriously limiting quantity and quality of seed in the country. An alternative technology of true potato seed (TPS) or use of botanical seed has shown great potential for producing both diseasefree healthy (quality) and cheaper planting materials for commercial potato production. This chapter describes the classical TPS technology and two novel potential TPSbased technologies in potato propagation.

Thrips: Thrips tabaci : Tuberose thrips Franklinella schultzei: Thripidae

These minute insects, preferring hot humid weather, rasp and suck the cell sap, causing bronzing, withering and drying up of leaves and flowers. This is the most serious pest on tuberose. Damage to young plants results in stunted growth.

Tuber crops grown in India include Cassava, Sweet potato, Dioscorea, Colocasia, Amorphophallus and minor tuber crops like Chinese potato, Arrowroot, Canna, Yam bean etc. Biotechnology can contribute solution to the major problems and realize greater benefits for tuber crops. Traditional breeding in tuber crops is difficult due to their heterozygous nature, low fertility, out crossing coupled with strong inbreeding depression. Many of the agronomic traits are polygenic and/or recessive which make breeding for such characteristics complicated. Biotechnology is a powerful tool to complement traditional breeding. Developments in the field of tuber crops biotechnology are discussed below.

Root and Tuber crops are the most important food crops of man after cereals. Tuber crops are efficient producers of carbohydrates especially under suboptimal conditions of rainfall, fertility and low input conditions encountered in tropics. The group contributes about 6 % of the world’s dietary calories. In fact, one out of 6 kg of human food comes from roots and tubers. Tuber crops find an important place in the dietary habits of small and marginal farmers especially contributing to food security of tribal populations. Tuber crops grown in India include Cassava, Sweet potato, Dioscorea, Colocasia, Amorphophallus and minor tuber crops like Chinese potato, Arrowroot, Canna, Yam bean etc. The biotechnology can contribute to the solution of the major problems and realize greater benefits for tuber crops.

1. Tuber crops Starches

Tropical root and tuber crops are rich sources of starch (Ghosh et al., 1988; Chadha and Nair, 1994; Moorthy, 1994) besides many vitamins, minerals etc (Table 1). In addition to food applications, they have important industrial uses; especially, cassava in view of the considerable starch content. Cereals form the major source of commercial starches in most developed countries, but cassava (Manihot esculenta Crantz) and to a lesser extent, sweet potato (Ipomoea batatas Lam.) tubers are used for starch extraction in India, Brazil, Thailand, Indonesia, Philippines and China.

Tropical tuber crops are an important group of subsistence crops in tropical and subtropical zones. Carbohydrates synthesised and stored in the form of starch in underground tubers are used as food by millions in under-developed countries. It is also used as raw material by many industries. Cassava, sweet potato, Chinese potato, edible aroids like elephant foot yam, taro, tannia and yams like greater yam, lesser yam and white yam are major tuber crops grown in India.

Tuber crops are mainly grown as rainfed with minimum cost of production. All are propagated through vegetative means and require fertile and well drained loose soil for proper root development. All roots crops require high dose of potassium for high productivity.Cassava is the most important starchy root crop grown in the tropics and is mainly cultivated in southern peninsular India. Introduced during seventeenth century by Portuguese, the crop played a significant role to overcome food shortage among the low income group of people in Kerala. Underground tuber is rich in starch and mainly consumed after cooking. Processed products like chips, sago and vermicelli made of tapioca are also popular in the country. Being easily digestible, it forms an important ingredient in poultry and cattle- feeds. It is also widely used for production of industrial alcohol, starch and glucose.