eChapters

Abstract

A field experiment was conducted at Mechanized Commercial Farm, College of Agriculture, Junagadh Agricultural University, Junagadh (Gujarat) during the Kharif-Rabi seasons of 2006, 2007 and 2008 to study the effect of tillage practices on yield of rainfed castor (Ricinus communis). The experiment was laid out in Randomized Block Design with four replications. The six treatments comprised viz., T_1- Conventional tillage (Cultivator + blade harrowing), T_2-Ploughing followed by cultivator and blade harrowing, T_3-Tillage through rotavator, T_4-Furrow opening through sub-soiling, T_5-Furrow opening through V-notch cultivator and T_6-Zero tillage (pre and post emergence herbicides + 2 hand weeding). Among the different treatments, the different growth and yield attributing parameters viz., plant height, number of spikes per plant, length of main spike, number of capsules per spike and test weight, seed and stalk yields, higher gross and net returns were recorded when field was prepared by ploughing followed by cultivator and blade harrowing. It also improved soil moisture content which was closely followed by tillage through rotavator (T₃) and furrow opening through sub-soiling (T₄).

The intricate dance between life and its atmospheric surroundings has shaped every living organism on Earth. From the microscopic bacteria thriving in extreme environments to the complex physiological systems of humans and large animals, weather and climate are not merely backdrops but active, pervasive forces dictating survival, distribution, behavior, and health. Weather, representing the short-term atmospheric conditions we experience daily— temperature, humidity, precipitation, wind, and sunlight—directly influences immediate comfort, activity levels, and susceptibility to acute events. Climate, on the other hand, embodies the long-term patterns and averages of these atmospheric variables over decades or centuries, acting as a fundamental determinant of ecosystems, biodiversity, and the sustained well-being of populations. This chapter delves into the multifaceted ways in which these atmospheric phenomena exert their influence. We will explore how thermal conditions drive physiological responses, from metabolic rate adjustments and thermoregulation to the very limits of endurance in extreme heat and cold. Beyond direct physiological impacts, we will examine the indirect effects, such as the role of climate in shaping

Introduction

The town Paithan is famous by it’s name Dakshin Kashi. Godavari river has pristine glory and great significance for Hindus.

Nath temple is situated on the bank of Godavari river. It is a holy place and that’s why it becomes a place of public gathering on Ekadashi, Aashadi Ekadashi, Poornima, Deepawali, Dasera etc. Every year during Chaitra lakhs of people gather.

But at the time of Sheshti, which occurs once in a year is a special event. Hence many fold increase of congregation compared to other melas. The particular small stretch of river near temple was highly polluted, due to mass bathing and other polluting activities. The warm weather shall alter the photosynthesis rates, biodegradation and affect BOD, DO, pH etc. Recent Nath Sheshti at Paithan during 20^th March to 22^nd March 2006, drew about one lakh of pilgrims and had a few special aspects of interests from an environmental point of view.

Considering all the above aspects, it was decided to assess the changes in quality of river Godavari during Nath Sheshti.

The Effective Climate Guidance (ECG) refers to information, tools, and frameworks designed to help individuals, organizations, and governments make informed and effective decisions and take appropriate actions to address climate change (Fig.7.1). It aims to provide practical, relevant, and actionable insights to navigate the risks and opportunities presented by a changing climate. Fig.7.1: Effective Climate Guidance (ECG)
7.1. Key Aspects of Effective Climate Guidance Include
• Materiality: Focusing on the most significant climate-related issues for the specific context (e.g., for a business, these would be the climate risks and opportunities that could impact its financial performance).
• Actionability: Providing clear steps or strategies that can be implemented.
• Decision-Usefulness: Ensuring the information is relevant and presented in a way that supports informed decision-making.
• Authority and Reliability: Based on credible scientific information and data.

Introduction
Social media has turned into an essential element of individuals’ lives students in today’s world of communication. Its use is growing significantly more than ever before especially in the post – pandemic era, marked by a great revolution happening to the recent investigations of using social media show that approximately 3 billion individuals worldwide are now communicating via social media (Iwamoto and Chun, 2020). This growing population of social media users is spending more and more time on social network groupings, as facts and figures show that individuals spend 2 hours a day, on average, on a variety of social media applications, exchanging pictures and messages, updating status, tweeting, favouring and commenting on many updated socially shared information (Abbott, 2017). In the digital age, social media have emerged as a powerful tool for disseminating agricultural technologies and knowledge. ICAR-Krishi Vigyan Kendra (KVK), Bengaluru Rural has effectively leveraged various platforms to bridge the gap between research and farmers, ensuring timely and relevant information reach the farming community. This article explores how KVK Bengaluru Rural strategically utilizes YouTube, Facebook, Instagram, and X (formerly Twitter) for technology dissemination.
I. Facebook
Facebook’s interactive nature allows KVK Bengaluru Rural to engage with farmers and build a strong online community. The fact that KVK’s Facebook channel has 5080 followers is a significant indicator of its reach and engagement within the farming community. The followers represent a substantial audience actively interested in the KVK’s activities and information, this indicates that, the KVK has successfully established a relevant online community. With this follower base, the KVK can effectively disseminate critical information, such as weather updates, market prices, and technological advancements, to a large segment of the local farming population. A significant follower count suggests that the KVK is perceived as a reliable and trustworthy source of agricultural information, farmers are more likely to follow and engage with organizations they trust.

Indian agriculture, accounting for 25% of the nation’s Gross Domestic Product (GDP), 15% of exports and 60% of the employment continues to be the mainstay of economy. Having achieved laudable success in agricultural production in the last 50 years (50 Million ton to 210 Million ton) India has transformed herself from a food deficit country to a food surplus country. Still there are many challenges, which Indian agriculture is facing, in a fast changing technical and socio-economic scenario. Relating to the natural resources and production base, water has emerged as the most crucial factor for sustaining the agricultural sector. India accounts for 16 percent of the world’s human population and nearly 30% of the cattle with only 2.4% of the land and 4% of the water resources.Even if the full irrigation potential is exploited, about 50% of the country’s cultivated area will still remain unirrigated, particularly with the current level of irrigation efficiency. The share of water for agriculture would reduce further with increasing demand from other sectors. But the water demand for agricultural purposes is estimated to increase in order to produce more cereals, horticultural produce and raw material for a fast expanding food industry. Efficient management of water is, therefore, key to future growth of Indian agriculture. The requirement of water by all sectors in 2025 is estimated to be 105 M ha m (Water Resources Development in India, 2010). Share of water for agriculture is expected to get reduced from the present level of 85 % to 69 % by 2025. On the other hand, the actual agricultural water demand is estimated to increase from 470 Billion Cubic Meters (BCM) in 1985 to 740 BCM in 2025. During the same period, the demand for non-agricultural use of water will multiply fourfold from 70 BCM to 280 BCM. The water use efficiency (WUE) in Indian agriculture, at about 30-40%, is one of the lowest in the world, against 55% in China.

14.1. Slope
It is a crucial topographic factor that affects water drainage, erosion and accessibility of agricultural machinery. Steep slopes increase the risk of soil erosion, and water run-off requiring erosion control measures such as contour ploughing or terracing. Slope also affects the availability of sunlight, as steeper slopes may cast shadows and influence microclimates within a field.
14.2. Altitude / Elevation
Elevation is the vertical distance of a point or location above a reference point, often mean sea level. It influences temperature, atmospheric pressure, and the types of crops that can be grown in an area. Higher altitudes generally experience cooler temperatures, which may limit the choice of crops that can thrive. Elevation affects the length of the growing season and influences the choice of appropriate crop varieties. In summary, elevation is an absolute measure of the vertical distance above a reference point (such as MSL), while it is a relative measure that describes the variation in elevation within a specific area or region. Elevation provides information about the height of a point, whereas it provides insights into the topographic features and slopes of a given agricultural landscape. Both elevation and relief are important considerations in agriculture as they influence factors such as water drainage, temperature gradients, and suitability for specific crops.
14.3. Aspect
Aspect refers to orientation of the slope (north, south, east or west). It affects the distribution of sun light; wind patterns and temperature gradients in a field. In the northern hemisphere, the north side of slope is often shaded while the southern side receives more solar radiation and heat, creating warmer microclimates and potentially influencing the choice of crops or planting strategies. Aspect can also impact the risk of frost or cold air drainage in certain regions. Whereas, in the southern hemisphere, the south side slopes get shaded and north facing slopes receive more solar radiation.
14.4. Relief
Relief refers to the variation in altitude between different points. It is a relative measure on changes in altitude across a particular landscape or agricultural area. The valley slopes are preferred sites for agriculture in mountain regions due to several reasons:
• The valley slopes offer relatively flatter terrain, making it easier for farming activities such as cultivation, irrigation and mechanization.
• The valleys tend to have better access to water resources such as rivers or streams which can be used for irrigation water.
• The valley slopes provide good sun exposure and protection from strong winds creating favourable microclimates for crop growth
• The natural drainage patterns of valleys help preventing water logging and ensure better water management.

Abstract

The present experiment was conducted to study the influence of weather parameters on the population dynamics of insect pests of rice during 2009-10 at ICAR-RC for NEH Region, Mizoram Centre, Kolasib, Mizoram. The result of the study indicated that, the mean populations of peak abundance of major insect pests rice crops during August were stem borer, flea beetle and gundhi bug. The Correlation studies showed that stem borer population a significant positively correlation was observed with maximum and minimum relative humidity. Nevertheless non significant negative correlation was obtained with maximum and minimum temperature. The finding of the present study indicated a positive non significant correlation with maximum relative humidity, maximum and minimum temperature where as negative insignificant correlation with rainfall and minimum relative humidity with flea beetle population. The highest minimum temperature showed a positive significant correlation with the Monolepta.

The ozone layer is a region in the Earth’s stratosphere where a certain amount of incoming solar radiation is absorbed. Over the last twenty years or so a series of man-made threats to it have been reported and each has been treated  with more gravity than the last. Now a-days such threats feature  regularly on the agendas of international conferences.

Ozone, Positive and Negative : Ozone, or trimolecular oxygen (O3) can be advantageous or exert harmful influence on human health, as well as that of other organisms. It is all depends on whether it is present in the troposphere or stratosphere (Fig. 8.1). In the stratosphere, ozone is a beneficial serving as a shield in screening out most of the damaging portions of ultraviolet radiation which have wavelengths between 290 and 320 nanometers. In the troposphere, ozone is a negative as it appears as a component of smog with a number of deleterious effects, as will be discussed below.

Abstract

As such in search of alternative to chemical insecticides against insect pest of rice resulted in identifying white muscardine fungus, Beauveria bassiana an entomopathogen out of several entomogenous fungi prevalent in rice ecosystem as the potential mycoinsecticides. The fungus has 78-87% virulence against rice hispa with  LC 50 value of 90.16. Under field situations it is required that the effectiveness of the bioagents are enhanced by combining them with compatible pesticides. A sublethal dose of a pesticide  would make the insect physiologically weak which makes it much more susceptible to the attack of the entomogenous organisms. In view of this, compatibility test was conducted with 14 different commonly applied insecticides at two different doses i.e., recommended and half of the recommended dose. In small scale field trial chloropyriphos at half of the recommended dose along with B. bassiana was the best treatment in controlling the pest along with increased yield of the crop consecutively for two years.

The objective of any cropping system is efficient utilisation of all resources such as land, water and solar radiation, maintaining stability in production and obtaining higher net returns. The efficiency is measured by the quantity of produce obtained per unit resource used in a given time.

Abstract

The groundwater targeting in hard rock aquifer systems is complex, because of the heterogeneity of the aquifer systems. The ground water mobility and stability in such aquifer systems varies because of the lithology, folded structures, fracture density, geomorphology, slope etc., These occur in various permutations and combinations and control the overall water holding and conducting capacity in different parts of the aquifer systems. Hence, one needs to analyse all the data so as to understand and bring out precise spatial models on the groundwater probability in hard rock aquifer systems. In the present study, the authors have carried out GIS based appraisals to understand the relation between the lithology and groundwater movement in hard rock aquifer systems of parts of Central Tamil Nadu covering 1300 sq.km. In the said study, GIS images were generated on the maxima zones of various aquifer parameters such as water level, width of aquifer depletion, transmissivity, permeability, specific capacity, storage co-efficient, optimum yield and recovery rate. These were overlaid with the lithology GIS image. Such an analysis has shown that, in general, the fissile hornblende biotite gneiss appears to have some control over the groundwater systems.

About 60 per cent of total arable land (142 million ha) in India is rain-fed, characterized by low productivity, low income, low employment with high incidence of poverty and a bulk of fragile and marginal land. Watershed development program is, therefore, considered as an effective tool for addressing many of these problems and recognized as a potential engine for agricultural growth and development in fragile and marginal rain-fed areas. The Government of India has accorded high priority to the holistic and sustainable development of rain-fed areas through the integrated watershed development program since the 7th Five Year Plan (1985-90) and since then a number of watershed programs have been specifically launched in the rain-fed areas with the sole objective to improve the livelihood of poor rural households in a sustainable manner.

Water is indispensable for human, animal and plant life. It is a major component of all organisms some of which contain more than 90% of water. Water is a constituent of protoplasm. It maintains turgidity of cells which is essential for stomatal opening, expansion of cells and for different physiological processes. Water is also required for translocation of nutrients and dissipation of heat.

16.1 Irrigation

Irrigation is generally defined as the artificial application of water to soil for the purpose of supplying the moisture essential for plant growth.

However, a broader and more inclusive definition of the term irrigation is the application of water to the soil for any number of the following six purposes —

1. To add water to soil to supply the moisture essential for plant growth.
2. To provide crop insurance against short duration drought.
3. To cool the soil and atmosphere, thereby making more favourable environment for crop growth.
4. To wash out or dilute salts in the soil.

The conservation of soil and water is very essential for sustainable production, environment preservation and balanced ecosystem. Fifty percent of total geographical area (329 m ha) of our country needs soil and water conservation measures. About 5334 million tonnes of soil is lost annually along with 10 million tonnes of fertilizer and other essential nutrients and organic carbon. Loss of nutrients is almost equal to their total production in India. In India about 70% of the cultivated area falls under the category of dryland conservation measures for soil and water and efficient utilization of these resources is needed in these areas. The fact that rainfed agriculture supports 44% of India’s human population and contributes 90 percent of coarse cereals and pulses, 80 percent of oil seeds and 65 percent of cotton and growing realization that further gains in productivity of crops and live stock will emanate from rainfed regions, leave no room for complacency in this regard.

In these areas, rainfall frequently occurs with high intensity that produces higher runoff due to non adoption of soil and water conservation (SWC) measures and poor permeability of the soil. As a result crop grown during rainy season often suffer from moisture stress due to inadequate moisture storage in the soil profile. Secondly soil erosion problems such as sheet, rill and even gully erosion are common in the region.

It has been reported that the black soils of peninsular region of India, under cultivated fallow gives runoff of about 23.4 percent of rainfall and results in a soil loss of 8.94 t ha^-1 at 1.0 percent slope (Verma et al., 1990). They further reported that the rate of siltation reduced by 83 percent within a span of five years due to adoption of agronomic measure of SWC. These studies clearly showed that soil erosion and runoff are the major factors causing land degradation in the region that needs appropriate SWC measures so that crop productivity could be maintained.

PGPR have shown potentiality against pests and diseases oc curring on crop plants. Wilt and collar rot diseases are caused by soilborne pathogens viz., Fusarium oxysporum fsp. lycopersici (FOL) and Sclerotium rolfsii respectively in vegetables. An attempt was made to manage the diseases with PGPR microbes and 142 PGPR strains were isolated from different vegetable crops. Among them two isolates viz., Bacillus amyloliquefaciens (BA1) and B. subtilis (BS2) were found highly effective in controlling the diseases.  Apart from the disease control, the isolates BA1 and BS2 also registered enhanced crop growth and yield in cowpea under field conditions. Species level identification of BA1 and BS2 was done through PCR amplification and sequencing of 16s rRNA. Both BA1 and BS2 clustered with Bacillus amyloliquefaciens and B. subtilis respectively.

Moisture deficit causing shortfalls in crop production is the characteristic feature of dryland agriculture. Other adverse factors viz., decline in soil fertility together with play of biotic stresses add to the complexities of dryland crop production. Added to the proven agronomic management to combat the problem of drought in dryland agriculture, there is the need to tailoring of suitable crop varieties which can yield reasonably well under conditions of moisture deficit (Varshney et al., 2021). In this context, the appropriate developmental rhythm along with the combination of the constellation of characters of the crop plant matching with the rainfall and the soil moisture availability patterns of the zone are the important considerations together with stability of yield (Hanson and Nelsen, 1980). This task being a complex one, the problem should be approached through multidisciplinary strategy that should buffer the genetic and breeding efforts.

Introduction

One of the most common concerns in irrigated agriculture is regarding water quality or salinity. Out of the ground water surveyed in different Indian States, as much as 84% is rated either saline or alkaline (Minhas 1996). Salinity management is very important for using saline water in irrigation safely. This requires an understanding of how salts affect soil as well as plants, of how hydrogeologic processes affect salt accumulation, and also of how cropping and irrigation activities affect soil and water salinity.

The objectives of management practices for getting optimal crop production with saline irrigation water include the prevention of salt build-up in soil which limit the productivity of soils and the control of salt balances in the soil-water system, as well as minimising the damaging effects of salinity on crop growth (Meiri and Plaut 1985). Amongst the various soil, water, and crop management options available, there is usually no single way to achieve safe use of saline water in irrigation but many different approaches and practices can be combined into satisfactory irrigation systems using saline water. The appropriate combination depends upon edaphic, hydrogeologic, climatic factors as well as social and economic condition of the farmer. Several practices interact with each other, and should be considered in an integrated manner, along with climatic and human factors. Because of the climate, the basic principles of saline water management need some adaptation, e.g. providing for a leaching requirement is not appropriate when the growing season for post-monsoon winter crops starts with a surface-leached soil profile, because it would increase the salt load. High salinities during the initial stages of growth are particularly harmful. Recommendations for effective management of irrigation water salinity depend upon local soil properties, climate, and water quality; options of crops and rotations; and irrigation and farm management capabilities

El Nino is the name given to the occasional development of warm ocean surface waters along the coast of Ecuador and Peru. When this warming occurs the usual upwelling of cold, nutrient rich deep ocean water is significantly reduced. El Nino normally occurs around Christmas and lasts usually for a few weeks to a few months. Sometimes an extremely warm event can develop that lasts for much longer time periods. In the 1990s, strong El Ninos developed in 1991 and lasted until 1995, and from fall 1997 to spring 1998.