Studies on Parental Synchronization in Flowering for Hybrid Seed Production in Onion (Allium cepa L.)

An experiment was conducted at the Indian Institute of Horticultural Research, Bangalore, in Rabi season during 2001-2002 and 2002-2003 to study the flowering of Cytoplasmic Male Sterile Lines CMS (A) and pollinator lines (C) of onion cv. Arka Lalima for working out effective synchrony in hybrid seed production. Results indicated that days to 100% flowering and days to complete flowering in a plant varied significantly in the parental lines and C line was found to be earlier than A line by 12 days and 25 days, respectively. The duration of flowering in a plant was also less in C line (23 days) than in A line (29 days). Due to lack of floral synchrony between parental lines, pollen availability becomes a limiting factor in hybrid seed production in cv. Arka Lalima. Delay in planting of C lines by a week after planting A lines resulted in synchronised flowering of parental lines at peak flowering stage. This also resulted in higher fruit set (80%) and hybrid seed yield (15g/plant) as against planting of A and C lines simultaneously (29.54% and 0.38g, respectively)

Plant growth promoting rhizobia: Challenges and opportunities

Modern agriculture faces challenges, such as loss of soil fertility, fluctuating climatic factors and increasing pathogen and pest attacks. Sustainability and environmental safety of agricultural production relies on eco-friendly approaches like biofertilizers, biopesticides and crop residue return. The multiplicity of beneficial effects of microbial inoculants, particularly plant growth promoters (PGP), emphasizes the need for further strengthening the research and their use in modern agriculture. PGP inhabit the rhizosphere for nutrients from plant root exudates. By reaction, they help in (1) increased plant growth through soil nutrient enrichment by nitrogen fixation, phosphate solubilization, siderophore production and phytohormones production (2) increased plant protection by influencing cellulase, protease, lipase and β-1,3 glucanase productions and enhance plant defense by triggering induced systemic resistance through lipopolysaccharides, flagella, homoserine lactones, acetoin and butanediol against pests and pathogens. In addition, the PGP microbes contain useful variation for tolerating abiotic stresses like extremes of temperature, pH, salinity and drought; heavy metal and pesticide pollution. Seeking such tolerant PGP microbes is expected to offer enhanced plant growth and yield even under a combination of stresses. This review summarizes the PGP related research and its benefits, and highlights the benefits of PGP rhizobia belonging to the family Rhizobiaceae, Phyllobacteriaceae and Bradyrhizobiaceae

Effect of Liquefaction Induced Lateral Spreading on Seismic Performance of Pile Foundations

Seismically active areas are vulnerable to liquefaction, and the influence of liquefaction on pile foundations is very severe. Study of pile-supported buildings in liquefiable soils requires consideration of soil-pile interaction and evaluation of the interaction resulting from movement of soil surrounding the pile. This paper presents the results of three-dimensional finite difference analyses conducted to understand the effect of liquefiable soils on the seismic performance of piles and pile groups embedded in stratified soil deposits using the numerical tool FLAC3D. A comparative study has been conducted on the performance of pile foundations on level ground and sloping ground. The soil model consists of a non-liquefiable, slightly cemented sand layer at the top and bottom and a liquefiable Nevada sand layer in between. This stratified ground is subjected to 1940 El Centro, 2001 Bhuj (India) earthquake ground motions, and harmonic motion of 0.3g acceleration. Parametric studies have been carried out by changing the ground slope from 0° to 10° to understand the effects of sloping ground on pile group response. The results indicate that the maximum bending moments occur at boundaries between liquefiable and non-liquefiable layers, and that the bending moment increases with an increase in slope angle. The presence of a pile cap prevents horizontal ground displacements at ground level. Further, it is also observed that the displacements of pile groups under sloping ground are in excess of those on level ground due to lateral spreading. Doi: 10.28991/CEJ-SP2021-07-05 Full Text: PD

Studies on the ontogenetic changes in the isozymes in Drosophila nasuta nasuta and Drosophila sulfurigaster neonasuta

Ontogenetic manifestations of four isozymes namely, acid phosphatase, alkaline phosphatase, α-esterase and β-esterase have been analysed in two closely related species- D. nasuta nasuta and D. sulfurigaster neonasuta. By adopting polyacrylamide gel electrophoretic technique 15 different developmental stages have been assayed. Electrophoretically homologous and distinct enzyme phenotypes for each enzyme system have been recognised in the two species under study. The implications of these findings are discussed

Groundnut Virus Diseases in the Asia-Pacific Region Summary and recommendations of the Fourth Meeting of the International Working Group 12-14 Mar 1995

Virus diseases cause economically significant losses to groundnut crops. The Four t h Meet ing of the International Working Group on Groundnut Viruses in the Asia-Pacific Region was organized by ICRISAT in cooperation with Khon Kaen University, Thai land, Peanut Collaborative Research Suppor t Program (Peanut CRSP), USA, the Samuel Roberts Noble Foundat ion, USA, Belgian Administration for Development Cooperat ion, Australian Cent re for International Agricultural Research, Directorate General for International Cooperat ion of the Ministry of Foreign Affairs, Th e Nether lands, and the Overseas Development Administration, UK. The Meet ing was held to develop strategies for the management of groundnut virus diseases in Asia. Thi s publication contains summaries of the papers presented at the Meet ing. Th e first two sessions deal with genome organization of economically impor tant groundnut viruses, and strategies for producing transgenic groundnut s with resistance to virus diseases. The third and fourth sessions cover country-specific situations for the management of groundnut viruses in Bangladesh, China, India, Indonesia, Myanmar , Nepal , Pakistan, and Vietnam. Specific recommendat ions for collaborative research on groundnut viruses in the Asia-Pacific Region are listed. The opinions in this publication are those of the authors and not necessarily those of ICRISAT. Th e designations employed and the presentation of the material in this publication do not imply the expression of any opinion whatsoever on the part of ICRISAT concerning the legal status of any country, territory, city, or area, or of its authorities, or concerning the delimitation of its frontiers or boundaries. Where trade names are used this does not constitute endorsement of or discrimination against any product by the Institute

Long-Term Evaluation of Crop Production Systems Based on Locally Available Biological Inputs in India

This chapter reports the results from a full decade of research conducted at the International Crops Research Institute for the Semi-Arid Tropics at Patancheru near Hyderabad in Telangana, India, between 1999 and 2009 on a rainfed vertisol. Appropriate use of such biological approaches has been previously reported to enhance the populations of soil microorganisms and macrofauna, thereby enhancing microbial transformations of different nutrients from their bound forms to available forms. Larger farms, because of their size, use their resources more extensively than intensively, and their higher total returns from agriculture usually derive more from their size of operation than from greater factor productivity or efficiency. Earthworms are widely accepted as having a beneficial influence on soil structure and chemistry that promotes plant, especially root, growth. A number of leguminous species offer opportunities to enhance biomass availability as cover crops or green manures

Vegetable pigeonpea – a review

Among sub-tropical legumes, pigeonpea or red gram (Cajanus Cajan (L.) Millspaugh) occupies an important place in rainfed agriculture. This crop has a wide range of uses and its use as fresh or canned green peas is common in parts of India, Africa, Central America and the Caribbeans. Vegetable pigeonpea is characterized by large pods and seeds because of easy shelling. Some parts of India prefer green pod colour but the study revealed that pod colour does not play an important role in determining the organo-leptic qualities of vegetable pigeonpea. The anti-nutritional factors like phyto-lectins are also present in pigeonpea, but it is heat sensitive and destroyed during cooking. Vegetable pigeonpea can be grown in backyards, field bunds and also as a commercial crop. The fresh seeds can also be frozen and canned for commercialization and export. The Dominican Republic stands first in exporting commercialized vegetable pigeonpea to United States and other countries. Vegetable pigeonpea is a good source of protein, vitamins (A, C, B complex), minerals (Ca, Fe, Zn, Cu), carbohydrates and dietary fibre. In comparison to green peas (Pisum sativum), the vegetable pigeonpea has five times more beta carotene content, three times more thiamine, riboflvin and niacin content and double vitamin ‘C’ content. Besides it has higher shelling percent (72%) than that of green peas (53%). These all factors indicate that pigeonpea is nutritionally rich vegetable and it can be used in daily cuisine

Networks, working groups, and their role in enhancing collaborative research in groundnut

Agricultural research networks are tools for strengthening agricultural research in developing countries by using existing facilities and staff more effectively. This tool avoids duplication of effort and can make available a critical mass of research effort to solve specific problems at a relatively low cost. This paper briefly reviews how networks are organized and operate; how scientists in national programs can strengthen their personal scientific capabilities and upgrade their research; whatpitfalls National Agricultural Research System (NARS) administrators must consider in becoming involved; and the ways in which International Agricultural Research Centers (lARCs) use networks to expand their information bases and share their material and information with NARSs. It then outlines the organization of the Asian Grain Legumes Network (AGLN) and other networks facilitating collaborative research on groundnut (Arachis hypogaea). Finally it examines the concept of Working Groups and how they are being used by the AGLN to focus and strengthen collaborative research on groundnut

ET mapping for agricultural water management: present status and challenges

Evapotranspiration (ET) is an essential component of the water balance. Remote sensing based agrometeorological models are presently most suited for estimating crop water use at both field and regional scales. Numerous ET algorithms have been developed to make use of remote sensing data acquired by sensors on airborne and satellite platforms. In this paper, a literature review was done to evaluate numerous commonly used remote sensing based algorithms for their ability to estimate regional ET accurately. The reported estimation accuracy varied from 67 to 97% for daily ET and above 94% for seasonal ET indicating that they have the potential to estimate regional ET accurately. However, there are opportunities to further improving these models for accurately estimating all energy balance components. The spatial and temporal remote sensing data from the existing set of earth observing satellite platforms are not sufficient enough to be used in the estimation of spatially distributed ET for on-farm irrigation management purposes, especially at a field scale level (~10 to 200 ha). This will be constrained further if the thermal sensors on future Landsat satellites are abandoned. However, research opportunities exist to improve the spatial and temporal resolution of ET by developing algorithms to increase the spatial resolution of reflectance and surface temperature data derived from Landsat/ ASTER/MODIS images using same/other-sensor high resolution multi-spectral images