eChapters

Soil-borne plant pathogens cause significant losses in the nursery plantation of agricultural, horticultural and forestry plantation stands. These pathogens can survive in the soil for many years through their resistant structures. Besides, the diseases caused by them are difficult to predict. Soil factors like soil type, texture, pH, moisture, temperature, level of organic matter and nutrient content influence the activity of soil-borne pathogens and diseases. In order to survive successfully, these pathogens compete with others for nutrition, space and other requirements. Understanding the dynamics of these pathogens and other microbial populations in the soil in relation to environmental conditions is essential for the successful management of these diseases.

Introduction

A forest is a complex ecosystem, predominantly composed of trees and shrubs, which usually form a closed canopy. They form a storehouse of a large variety of life forms such as plants, mammals, birds, insects, reptiles etc., besides being the most important habitat of the microorganisms and fungi, which do the important work of decomposing dead organic matter, thereby enriching the soil. Nearly 4 billion hectares of forests cover the earth’s surface, roughly 30% of its total land area. The forest ecosystem has two components- abiotic and biotic. Climate and soil type form a part of the non-living component and the living component includes plants, animals and other life forms. Plants include the trees, shrubs, climbers, grasses and herbs in the forest.

Introduction

Forest trees constitute ~82% of the continental biomass and harbour >50% of the terrestrial biodiversity. They also help to mitigate climate change, and provide a wide range of products that meet human needs, including wood, biomass, paper, fuel and biomaterials. Field-grown trees are routinely exposed to environmental stress. Current and predicted climatic conditions, such as prolonged drought, increased salinisation of soil and water and low temperature episodes pose a serious threat to forest productivity worldwide, affecting tree growth and survival. According to the reports of the Intergovernmental Panel on Climate Change, these stresses will increase in the near future because of global climate change.

Introduction

Land is one of the most important resources on which human beings depend. The rate of soil degradation is continuously increasing with the advancement of science and technology, industrial expansion, urbanisation and population explosion. The most important cause of land degradation is the destruction of forests and other vegetation in sloping lands, riverbanks and other areas sensitive to damage (Pramod and Mohapatra, 2012). Anthropogenic activities like over grazing, wood cutting and burning have intensified land degradation, resulting in soil deterioration all over the world (Jin, 2002). Vegetation acts as a protective cover against the forces of wind and water, protecting the soil from being washed or blown away and preserving the physical and hydrographic balance of nature (Jain and Singh, 1998).

Introduction

Agroforestry denotes a sustainable land and crop management system that strives to increase yields on a continuing basis, by combining the production of woody forestry crops (including fruit and other tree crops) with arable or field crops and/or animals, simultaneously or sequentially, on the same unit of land and applying management practices that are compatible with the cultural practices of the local population. In Jammu and Kashmir, agroforestry systems have been practiced since centuries and passed from generation to generation. These systems were built on the foundation of protecting and planting trees. These systems in the past have made the hill people self- sufficient and well- nourished.

Apricot is an important fruit grown in the dry temperate and mild-hill regions of India. The fruit belongs to the family Rosaceae and genus Prunus. The original apricots are native to China, whereas wild apricot, which is known as ‘Zardalu’, is indigenous to India. Wild apricots are found at a low altitude of 1500 m and as high as 4000 m a s l. The cold hardy trees are hardier than peach and almond and can tolerate winter temperatures as low as -30ºC. They are drought- tolerant and can be grown in a variety of soils, but deep, fertile and well- drained loamy soil with a pH value of 6.0 to 6.8 is suitable for their growth and development. Apricots are found the world over at low altitudes of 150 m and as high as 4000 m a s l.

Introduction

The term ‘multipurpose trees’ covers all woody perennials used in agroforestry. Many authors have given many definitions of MPTs and MPTS. Burley and von Carlowitz (1984) reviewed many definitions and gave a synthesised definition which states that “multipurpose trees and shrubs (MPTS) are those which are deliberately grown and kept and managed for preferably more than one intended use, usually economically and/or ecologically motivated major products and / or services in any multipurpose land use systems, especially agroforestry systems”. The Forestry /Fuelwood Research Development Project (1992) precisely defined ‘multipurpose trees’ (MPTs) to mean tree species that are grown to provide more than one significant crop or function on the farm.

Conifers are valuable natural resources of the country, which contribute substantially to its socio-economic development by providing goods and services to the people and industry. They generate considerable revenue and also play a major role in enhancing the quality of the environment by influencing the basic life support system. Unfortunately, however, they have been subjected to over- exploitation and biotic pressure in the last many years, thereby threatening the very existence of some species such as yew, chilgoza pine etc. The genus Pinus is, in fact, one of the largest and most divergent of the coniferous genera, comprising about 95 species and numerous other varieties and hybrids. They are distributed widely in the northern hemisphere, chiefly in the temperate and cold climates.

Vermicompost is a nutrient-rich, microbiologically-active organic amendment that results from the interaction between earthworms and microorganisms during the breakdown of organic matter. It is a stabilised, finely divided peat-like material with a low C:N ratio, high porosity and high water-holding capacity, in which, most nutrients are present in forms that are readily taken up by plants. Earthworms act as mechanical blenders, and by fragmenting the organic matter, they modify its physical and chemical status by gradually reducing the ratio of C:N and increasing the surface area exposed to microorganisms, thus making it much more favourable for microbial activity and further decomposition.

Introduction

Biofertilisers are defined as preparations containing the living cells or latent cells of efficient strains of microorganisms that assist in the uptake of nutrients in crop plants by their interactions in the rhizosphere, when applied through seed or soil. They accelerate certain microbial processes in the soil, which augment the extent of the availability of nutrients in a form easily assimilated by plants. The increasing pressure of human and livestock population, indiscriminate extraction of forest produce, regular forest fires and mining activities have resulted in soil erosion, loss of fertility and moisture content and decreasing productivity of forests, which pose manifold problems for the restoration of the ecosystem.

Introduction

In India, about half of the geographical area is classified as degraded and as such, these areas are not able to produce services of any value (Khan, 1988). So, there is growing concern about the serious degradation in the quality of forests, besides the significant reduction in the tree cover in the country. To answer the prevailing conditions in the current era, one needs better nursery management to produce quality planting stock.

Forest nurseries are an essential part of forestry programmes, which cover traditional or intensively managed commercial forestry with introduced species. Field plantations should do with more productive species, but of improved quality and vigour. In order to encourage the forest tree culture, the use of quality planting stock and its subsequent management is very important.

Introduction

Forest restoration is a complex process that requires many steps to ensure successful forest establishment. These steps include choosing suitable tree species and provenances, applying nursery cultural practices to produce quality seedlings and making site modifications to improve the physical environment of the restoration site (Grassnickle, 2000). Conifers are the most important tree species of the western Himalayas and J&K. There are about 16 species spread over 9 genera in 3 families. Among these families, Pinaceae, with seven species in 4 genera, is the most dominant, while Taxodiaceae, with 2 species in 2 genera, is the least represented. Out of the total taxa, 7 species belonging to 5 genera are exotic and exist in cultivation only.

Introduction

Plant growth regulators are defined as small, simple chemicals produced naturally by plants to regulate their growth and development and are essential for regulating their own growth. They act by controlling or modifying plant growth processes, such as formation of leaves and flowers and elongation of stems.

In modern forest nursery raising, the benefits of extending the use of plant hormones to regulate the growth of economically important plants have been established. There are two possible goals in inducing trees to form floral buds, in particular, female buds. The first is to achieve precocity. Precocious flowering in normally immature trees can provide advantages in breeding and seed production because it overcomes a substantial seed production delay intrinsic to late-maturing conifers. The second reason is the phase change from juvenile growth to mature growth. The induction of either precocity or increased male flower and female cone formation are generally the result of applied treatments. A few studies have focused on the intrinsic physiological differences between high and low producing clones.

Part A

Counting of Seeds in a Seed Lot

Counting of seeds is essential in order to estimate the number of seeds required for planting in a nursery or direct sowing or where seeds are valuable and are sold or purchased on number basis. However, in practice, it is difficult to count the seeds in the entire lot. Alternately, the whole lot is weighed accurately. From the whole lot, 5-6 small seed samples of 100 g each are randomly selected. The number of seeds in these samples are counted. The average of these samples is then applied to the whole seed lot in order to calculate the number of seeds.

Introduction

The applied aspect of tree improvement consists of the development of improved trees followed by the mass production of the improved stock. No programme will be successful until both have been achieved. Too often, the improvement of forest trees is obtained without sufficient concern about how the improved material is to be reproduced and used on an operational scale. The better trees can be regenerated through seed or by vegetative propagation. All tree improvement programmes must have seed production at some stage of their development if continued gains are to be achieved. This is even true for the programmes using vegetative propagules for large-scale operations of planting; seed is needed for the development of outstanding trees, from which, vegetative propagation can be achieved.

Introduction

Germination is a critical stage for the establishment of plant species, especially those that grow naturally in arid and semi-arid environments (Alouani and Bani Aameur, 2004). Several factors may influence germination percentages in natural environments. Among these factors, seed dormancy contributes in part to germination failure of many species under adverse environmental conditions (Bewley, 1997). There are two categories of dormancy: coat- enhanced dormancy (seed coat dormancy), where the embryos isolated from these seeds are not dormant and embryo dormancy (internal dormancy), where the embryos themselves are dormant (Bewley, 1997;

Seed is defined as a ‘matured ovule’ or a reproductive unit formed from a fertilised ovule consisting of an embryo, food store and protective coat. These essential constituents are common to all seeds in different groups of seed bearing plants. The knowledge of seed morphology is essential for artificial regener ation as it can influence the collection, processing, storage and treatment of seeds. The external and internal morphologies of seeds are stable. Therefore, they provide reliable criteria for the positive identification of unknown seeds.

Importance of Tree Seed

India is primarily an agriculture based economy, which implies, agriculture dominates the nation’s economic landscape. In the course of socioeconomic growth, agriculture is crucial. Around 58 per cent of the population in India relies only on agriculture for their livelihood. India is enriched with various agricultural and horticultural crops with diversified agro-climatic conditions and different soil types. India is one of the leading producing countries of cereals, pulses, oilseeds, fruits, vegetables etc. India is also have a prominent scope in allied sectors of agriculture includes livestock, poultry, forestry, sericulture etc. Among such crops, Moringa is the selected crop for this research study. Moringa (Moringa oleifera), which is popularly known as ‘Drumstick’ belongs to the family Moringaceae. Moringa is basically a native crop of India. This crop has its own therapeutic properties with greater nutritional content. Especially in South Indian cuisine, moringa pod is a highly regarded vegetable because of its distinctive flavour and fragrance.

This chapter analytically represents the results of the empirical research study with the appropriate discussion on the basis of analysis.

6.1. Results of data collected from moringa growers of Tamil Nadu

6.1.1. Visualisation of descriptive statistics

This Table-6.1 presents 18 independent variables (x1-x18 ) and 5 dependent variables (y1-y5 ) in terms of their descriptive statistics viz. Minimum, Maximum, Range, Mean, Standard Deviation (S.D.), Variance and Co-efficient of Variation (C.V.).

of moringa growers, the maximum years of experience is 44 years and the minimum years of experience is 3 years. The Range of this variable x1 was found to be 41. The mean value of experience was found to be 16.033 years, with the Standard Deviation of 8.324 and Variance of 69.289 for the total distribution taken for the study.

5.1. Research methodology

Research methodology is a thorough investigation plan and the manual for conducting the research. This chapter’s examination of methodology aims to help readers comprehend the ideas, strategies, and tactics used to plan a study, gather data, analyse it, and interpret it in order to reveal reality and develop theories. This chapter has been classified under various sub headings for clear understanding:

(i) Locale of research.

 (ii) Pilot study.

 (iii) Methods of sampling.

 (iv) Variables and their empirical measurement.

 (v) Preparation of the interview schedule.

 (vi) Tools and techniques of data collection.

 (vii) Statistical analysis and interpretation of data.