eChapters

ABSTRACT

Expert systems are very popular computer programs designed to simulate the problem solving behavior of human thinking in a narrow domain. The world has changed into a global village. Information has become a powerful commodity and agricultural production has evolved into a complex business requiring the accumulation and integration of knowledge and information from many diverse sources. Rice is the staple food of over half the world’s population. India is the second largest producer and consumer of rice in the world. In order to remain competitive, the modern farmer often relies on agricultural specialists and advisors to provide information for decision making. In order to alleviate this problem, expert systems were identified as a powerful tool with extensive potential in agriculture. Rapid development of web technology benefits our decision-making and various activities in agriculture. With this background, web based rice expert system has been developed for diagnosing pest and disease problems of rice crop.

Key Words: Rice, Expert system, Knowledge, Decision making

Introduction

The innovative use of web technologies enables us to reach both local and distant users much more easily and effectively. Technologies such as email and Web provide tremendous opportunities for library & Information Scientists to deliver the information to the desktops of users. Web offers significant advantage by integrating different library & information services with a common user interface offered by Web browsers.

INTRODUCTION

The World Wide has become one of the most important media for sharing information resources, digital documents, images, movies and various other types of resources. The research results, new findings, and opinions can also be put on the web from any where at any time. Owing to the dynamic nature of web information, the contents of many websites and their web pages are constantly being updated to reflect the latest changes.

The Web has also freed the user‘s dependence on library resources for finding information related to address and contact details of a person/institution, contents pages of books, journals, etc. Looking at the web has become an innovative trend in the reference service to complement dated print sources. At present many academic institutes in India have their own website and present all kinds of information about themselves. Information content is, however, one thing; Web site design and organisation is quite another matter. The existing institutions of Web sites are as different as are the institutions because even a high-quality institution may have a low-quality Web site that turns users off. Obviously, different institutions have a wide range of target groups, level of service, resources etc. Stover (1997) has outlined the different types of Web sites that academic, public and special libraries have created.

Abstract

A huge technical improvement in Information Technology (IT) has made new instruments (e.g. WEB-GIS, Open Source platforms, DBMS with geometric data) available. Distributing geospatial information on the Internet is an enforcing factor for information providers. For dissemination of spatial data, Web-GIS technology can be used, which is amalgamation of several information technologies. Open Source is a philosophy of providing software with better quality, more flexibility, and lower cost. This paper explains the use of Open Source Web-GIS which provides a fast and globally reachable way not only to represent the information about natural resources through maps and statistics but also possibility of processing the information interactively on web.

Keywords : Web-GIS, Open Source, PostgreSQL, PostGIS, GeoServer, Wetlands

1.0 Introduction

India is blessed with diverse and abundant resources. India has been witnessing tremendous growth which has impacted practically every aspect of environment and the common man. Natural resource has been tremendously in use due to increase in population growth, thus generation, dissemination and sharing of information regarding natural resources and data amongst all stake holders have become a necessity. The utilization of modern technologies such as remote sensing, GIS which are effective in management of natural resources as user can store, retrieve and model the spatial information. Web media is playing a vital role in making people aware about the importance and conservation of natural resources. We are presenting such efforts with use of Free and Open Source Software (FOSS) tools.

The vision 2020 document of the Department of Agriculture and Co-operation envisages that “the tools of ICT will provide networking of Agriculture Sector not only in the country but also globally and the Centre and State Government Departments will have reservoir of databases” and also “bring farmers, researchers, scientists and administrators together by establishing ”Agriculture Online” through exchange of ideas and information”. To get realize the vision 2020 a large number of agriculture based websites and web portals have been established in India which is working for wellbeing of farming community. Majority of agricultural websites and web portals are providing need based technological information to the farmers as well as extension professionals. To revitalize our extension system these web based services can be used as ICT tool by extension personnel and farmers also. Therefore, to get access services from these websites and web portals or to replicate these ideologies in other part of country, elementary knowledge of working process and services available on these websites & web portals is essential. This chapter will provide a brief description about major ICT based projects dedicated to Indian farmers.

Weed Biology

Weed biology is the study of the establishment, growth, reproduction, and life cycles of weed species and weed societies/vegetation. Weed biology is an integrated science with the aim of minimizing the negative effects, as well as using and developing the positive effects, of weeds.

Life Cycle - Based on life cycle weeds are classified as annuals, biennials or perennials.

Annuals

Annuals complete their life cycle from seed in less than one year. There are two types: summer and winter annuals. Summer annuals germinate in the spring, mature, produce flowers and seeds and die before fall. Winter annuals germinate in the fall, overwinter in a seedling or rosette stage, mature, produce flowers and seeds, and die in the spring or early summer. Because of the seedling stage, annual weeds are generally easy to control. There are usually few annual weeds present in low bush blueberry fields.

Biennials

Biennials generally complete their life cycle over two years. The first year the seeds germinate and form a basal cluster of leaves and a tap root. The plant overwinters in this stage. During the second year the weed produces a flower stalk, sets seed and dies. Examples of biennial weed are evening primrose and wild carrot.

Methods of Weed Control

Prevention, eradication and control are the fundamental principles of weed control.First basic step is to prevent the infestation of a weed(s) in a locality in order to avoid their further spread. If one fails in preventing spread of weeds, eradication step must be adopted. Eradication is limited on a very small scale and adopted only when suitable methods of complete weed removal are available as eradication is cent per cent control of weeds alongwith its root system and other propagative parts. Further, if one fails in prevention and eradication techniques then different weed control methods must be strictly followed in which the objective is to bring down the weed population (with any method) to a level that economical crop yields are possible. The aim of each weed control method is to achieve reasonable good control of weeds. Following methods for controlling weeds are very common:

Preventive Methods

Try to prevent spread of weed seeds/vegetative parts with the adoption of following preventive techniques.

Weeds have been a problem to agriculture ever sine man started cultivation. Weed species by and large invade cropped areas and account for large economic losses to the farmer. Weeds are economically more important than insects, fungi or other pest organisms (Savary et al. 2000, 2006). Globally, weeds cause the highest potential loss to crop production (34%), with animal pests and pathogens being less important (losses of18% and 16% respectively). The loss in production due to weeds has been estimated as 5% in developed countries. It is around 10% in developing countries and 25% in least developed countries. (Oerke, 2006)

Weed Ecology

Ecology is the study of reciprocal relationship between organisms and their environments. The ecology of weed is thus concerned with growth characteristics and adaptations that enable weeds to exploit the ecological niches left open in those environments altered by man for his use and the survival mechanisms where by weeds persist in such environments. In simple words weed ecology is reciprocal relationship of weeds with their environments. Weeds grow voluntarily in all crops raised by human beings since ancient ecology of weeds is divided into two categories (types).

1. Weed Auto Ecology

It is study of only one population i.e. how an individual species in a population interacts with its environment at all stages of its life cycle. So, in case of auto ecology competition within same species (intraspecific) or with crop plants (inter specific competition) is studied.

2. Weed Synecology

The study of relationships between communities of different weed species with their environment is called weed synecology. Different weed species grow in certain combinations and in specific patterns in the ûeld. The population of different weed species interact with the external environmental conditions and among themselves. Weed communities differ from field to field and crop to crop in the same locality. The community character is dynamic and changes in form and composition of weed flora takes place in course of time due to some external and internal factors prevailing in the community. This process is called ecological succession. With the passage of time there will be series of changes in the composition of weed community which ultimately results in stable community. This is termed as climax community.

Abstract

Invasion of field crops, orchards and waste-lands by weeds is a matter of concern for farmers and foresters because of the drag they inflict on productivity and the increase in cost of production involved in weed control. Science-based technologies offer workable and reliable recourse to minimizing and/or eliminating these losses to promote healthier and rewarding livelihoods. While studies have been conducted to combat brush-weed in waste-land and plantations, little work has been done on such aspects as biological control of weeds, development of herbicide resistance in weeds, and allelopathic interface of crops and weeds. In this chapter, attempt is made to assess the economics of weed management in major crops. Aspects of R&D on weed management that should be addressed for safeguarding yield in the future are highlighted with particular reference to situation in western Himalaya.

Weeds are unwanted and undesirable plants which interfere with the utilization of land and water resources and thus adversely affect crop production.

Classification of Weeds

Weeds can be classified in three different manner based on morphology, life cycle, habitat and origin.

6.1 Introduction

The birth of modern conventional agriculture coincides with industrial revolution. The identification of N, P and K as critical factors in plant growth led to the manufacture of synthetic fertilizers. While chemical fertilizers and pesticides have existed since the 19th century, their use grew significantly in the early 20 century with the invention of Haber-Bosch method for synthesizing ammonia. The rapid farm mechanization, especially in the form of tractor and combine harvester coupled with science-driven innovative management methods and resources led to the efficiency of enabling outputs of high quality produce per unit area and time.

Weeds have been existing on the earth ever since the man started domesticating /cultivating plants and animals around 10,000 B.C. and recognized as a problem since then. The battle against weeds is a never ending one and often the costliest agronomic input for successful crop production. Weeds are most under estimated crop pests in tropical agriculture although they cause higher reductions in crop yields than other pests and diseases. Of the total annual loss of agricultural produce from various pests in India, weeds roughly account for 37%, insects for 29%, diseases for 22% and other pests for 12%. Weeds decrease quantity and quality of the produces [food, fibre, oil, forage/ fodder, animal products (meat and milk)] and cause health hazards for humans and animals. Therefore, weed control is very important for a successful crop production.

Abstract
India shares one fourth of global annual grain legume production and is also largest consumer of it. Weeds are the most severe and widespread biological constraint on agricultural production systems and cause damage to cropped and non-cropped lands. They reduce crop yield and degrade the quality of the produce, besides raising the cost of production. The grain legumesare commonly grown under rainfed/dry land conditions and hence do not receive the best management practices that are required for maximization of crop productivity. Among various production inputs, weed management was found to be the most important one contributing about 31% in pigeon pea, 110% in urdbean and 60 % in mungbean towards total productivity. Effective weed management in grain legumes is essential for optimizing
crop yield and quality. This process involves a multi-faceted approach that integrates cultural, mechanical, and chemical methods to address the challenges posed by diverse weed species and varying environmental conditions. Traditional single-method approaches often fall short due to the complexity and variability of weed problems like development of resistance in weeds. Therefore, an integrated weed management approach becomes effective, combining timely interventions with adaptive strategies to manage weed competition throughout the growing season. This approach not only enhances crop competitiveness and yield but also offers economic and environmental benefits by reducing reliance on broad-spectrum herbicides and promoting sustainable practices. Continuous monitoring and adjustment
of weed management strategies are crucial to effectively tackle evolving weed populations and changing conditions, ensuring long-term success in grain legume cultivation.
Keywords: Broad-spectrum herbicides, Crop productivity, Crop weed competition, Grain legume, Integrated weed management

1. DEFINITIONS

Various definations of weed have been proposed. Weed is defined as a valueless plant growing wild, especially one that grows on cultivated ground to the exclusion or injury of the desired crop. Weed means any undesirable or troublesome plant, especially one that grows profusely where it is not wanted. The weed have also been defined a plant considered undesirable. Weeds are commonly unwanted plants in human-controlled settings, such as farm fields, gardens, lawns and parks. A weed may be any plant that grows or reproduces aggressively, or is outside its native habitat. Some plants that often are considered to be weeds are Bermuda grass, creeping Charlie, dandelion, golden rod, poison ivy, ragweed, wild carrot, wood sorrel, nutsedge etc.

Indian tea has a global reach being the second largest tea producer in the world. Indian tea is one of the finest in the world. Darjeeling tea is the first product to get a geographical indicator tag in India. 83 % of the tea produced in India is from Assam and West Bengal and 17% from the south Indian states of Kerala, Karnataka and Tamilnadu. Weeds are a major problem in tea gardens.

Weed flora

Drymaria cordata, Bidens pilosa,, Cynodon dactylon, Panicum repens, Celosia argentea, Ageratum conyzoides, Centella asiatica, Borreria hispida, Oxalis latifolia, Mikania micrantha, Paspalam conjugatum,

Weeds are unwanted and undesirable plants which interfere with the utilization of land and water resources and thus adversely affect human welfare. They can also be referred as plants out of place. Weeds rank first among different agricultural pests causing crop loss. About 30,000 species of weeds have been listed in the world, out of which 18,000 cause serious damage in different ways resulting in considerable loss to agricultural production.

The term weed can be described in many ways. In general, it is said that weed is a plant, which is not sown by the farmers or which is out of place. Weed is defined as the unwanted, undesirable plant, growing out of its proper place, which interferes with the utilization of natural resources, is prolific, persistent, competitive, harmful and even poisonous in nature and can grow in adverse climatic conditions.There are more than 30,000 species of weeds distributed world over, out of which 18,000 are noxious and cause serious losses. Around 250 species are causing serious economic losses. Weeds in orchards reduce crop yields by competing for moisture, nutrients, light and space. They also act as a host for insect pests and diseases. When they become large, they interfere with orchard operations as well as water bodies. There are some weeds, which are parasitic partially or completely on the host tree e.g. striga and loranthus, in mango.

Rice is the primary food source for half of the Asian population. Nearly 2,000 million in this region obtain 60 to 70 per cent of their calories from rice and its products. Considering the importance of the crop, United Nations General Assembly declared 2004 as the “International Year of Rice” (IYR). In India, the crop covers one-fourth of the total cropped area. About half of the Indian population use rice as their staple food.

Rice based cropping systems are not only important for food security but also for maintaing an ecological balance. Low land rice fields conserve water and prevent runoff .They preserve the sustainability of the ecosystem.

Weed is a plant that is growing in the wrong place. Weeds have many mechanisms and characteristics that enable them to compete, having thick waxy cuticle leaves that can be resistant to some chemicals, fast reproduction methods, the ability to reseed in 6 week cycles and deep tap roots enabling the weed to survive in compacted dry ground conditions.

There are many reasons to control weeds in annuals/biennial and perennial ornamentals. Weeds compete with the plants by absorbing essential nutrients and water, or by blocking light or air circulation. Weeds dramatic reduce the growth of the plants. The greatest damage is often done when the weeds and ornamental plants are small. Weeds also interfere with harvesting by physically hindering. They lower flower quality further by harbouring insects, such as whiteflies, thrips mites, slugs, snails and/or diseases.

Growing under optimal conditions for the flower will reduce the ability of weeds to compete against the crop. Controlling humidity/ventilation, water, light, pH, nutrients and temperature all figure prominently in providing flower optimal conditions. A plant health strategy to greenhouse weed control contains three principal elements, prevention/sanitation, evaluation of water quality and using all controls available physical, cultural and chemical. Prevention and sanitation can include the use of mulches in orchidhouse weed control. Rice hulls, perlite, pumice, corn gluten meal bark, Penn Mulch - pelletized recycled paper and human hair have all been used for this purpose. Prevention also includes, eliminating air borne weed seeds from entering the greenhouse by screening vents and other openings and preventing perennial weeds from growing under foundations. A 1-3 meter weed free zone should be maintained immediately adjacent to the greenhouse.