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The enhanced laboratory and field emergence characteristics of osmo- and halo-primed tomato seeds (cv. Pusa Ruby) were related to changes in hydration–dehydration kinetics, modified sorption properties and nuclear magnetic resonance (NMR) relaxation behaviour of humidified and imbibed seeds. Water sorption isotherms were constructed for primed and unprimed seeds by equilibrating to different water activities (aw) at 25°C. Analysis of the isotherms by the D'Arcy–Watt equation revealed that priming reduced the number of strong binding sites and the associated water content, and increased significantly the number of weak binding sites and the associated water content. This redistribution of water, which increased the availability of seed water, may be the reason for the higher speed of germination of primed seeds. The changes in transverse relaxation time (T2) of seed water and its components, measuredin vivousing nuclear magnetic resonance spectroscopy, showed interesting differences between primed and unprimed seeds. With an increase in humidification time, the T2of primed seeds could be resolved into three components with varying mobilities, while the control seeds had only two components until 10 d of humidification. During imbibition, the third component appeared after 2 and 6 h in primed and control seeds, respectively. This component disappeared after the germination process started in all treatments. The third fraction, with very low molecular mobility, which accounted for about 40% of the proton population, was assigned to hydration water of macromolecules. Hence, we propose that better performance of primed seeds may be attributed to the modifications of seed water-binding properties and reorganization of seed water during imbibition, so as to increase the macromolecular hydration water required for various metabolic activities related to the germination process.

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The present study was carried out to determine the physical as well as physiological properties of three fresh pea seed lots (cv. Arkel) with moisture content and germination percentage varying from 14.94% to 28.04% dry basis and 80% to 60% respectively. This variation in moisture content and physiological parameters was obtained using accelerated aging (40C and 100% RH). The geometric (spatial dimensions, sphericity and surface area), gravimetric (terminal velocity, true density, test weight, bulk density and porosity), frictional (angle of repose, coefficient of static friction), mechanical (compressive strength) and physiological parameters (seedling dry weight, seedling length, vigour indices, electrical conductivity and root growth parameters) were determined for the selected seed lots. The effect of moisture content on seed lots was significant (R 2  0.947) on physical and physiological properties of seed lots. This study may help in designing seed priming prototype suitable for pea seeds.

The knitting of information and modern electronic technology with agricultural production system to determine, analyze and manage the critical temporal and spatial factors of farm for maximizing profitability, sustainability and environmental protection is need of hour. In this context, robot (Arial, Ground and Under-water) can play an important role. Aerial Robot is also commonly known as Unmanned Aerial Vehicle (UAV) or Drone. It may be boon for management of agricultural production as it can focus on small crop fields at lower flight altitudes than other regular aerial vehicle to perform site-specific farm management operation with higher precision. It can also address adverse crop and land prerequisites, where use of conventional machines is challenging, e.g. spraying under wet paddy field, tall crop sugarcane, pigeonpea etc. Embedding the available technologies and methods for meeting functional, operational and structural requisite, specifically for the crop and land environment with Arial Robot is of utmost importance. On the basis of system range, accuracy, resolution, and precision, sensitivity, linearity, offset, hysteresis and response time of different sensing and control technologies, e.g. optical, near infrared, thermal multi-spectral, hyper-spectral, Light Detection and Ranging, radio frequency and sonar .This paper presents an overview of research involving the development of UAV technology for agricultural production management. Technologies, systems and methods are analyzed for in situ integration under Indian farm conditions. The limitations of current Arial Robot for agricultural production management are deliberated, moreover forthcoming needs and suggestions for development and application of the technology in agricultural production management are projected.

A solar-powered vending cart was designed and developed for storage of fruits and vegetables. It was tested for its performance during summer season. The minimum and maximum drop in temperature ranged between 8.1C and 11.2C, and the increase in relative humidity was observed to be up to 15% and 25% inside the vending card chamber in June. The requirement of water ranged between 16.5 and 20.0 litre/day. There was considerable effect on physiological loss in weight of different vegetables kept either inside or outside the mobile chamber. The freshness and shelflife of vegetables increased substantially after storage in the cart.Keywords: Evaporative cooling, fruits and vegetables, solar-powered cart, storage.FRUITS and vegetables account for 92.3% of the total horticultural production in India. Around 2.1% of the production is used by processing industries; the remaining produce is either consumed soon after harvest or stored for later use in fresh form. It is therefore important that effective exploitation of the export capability of fruits and vegetables is ensured. Since fruits and vegetables are perishable, their magnitude of loss is estimated at 35-40% due to poor post-harvest management resulting in huge financial loss each year. India wastes fruits and vegetables each year equivalent to the annual consumption of the United Kingdom.Absence of sufficient storage facilities after harvest results in deterioration in the quality in fruits and vegetables that reach the market. This has an immediate impact on the distribution and availability of the required amount for human consumption. The most imperative parameters influencing the post-harvest life and quality of horticultural produce are temperature and relative humidity (RH). The deterioration in quality of produce after harvest is the result of physical, biochemical, physiological and biological processes, the rates of which are influenced primarily by product temperature (at harvesting) and RH in the vicinity. Rate of spoilage increases 2-3-fold with each 10C rise in temperature. The vital activities of tissues, for example, transpiration, respiration, ripening, etc. take place even after harvest. Fresh produce needs low temperature and high RH during storage. Immediate cooling is important to minimize quality loss when the produce is harvested at high temperatures or at an advanced stage of maturity. Preserving such commodities to remain fresh demands that the chemical, biochemical and physiological changes are restricted to a minimum by close control of temperature and RH. The high cost involved in developing cold storage or controlled atmosphere storage on a movable cart is a pressing problem in India and several developing countries. Evaporative cooling is an efficient and economical means for reducing the temperature and increasing RH in an enclosure.Evaporatively cooled storage has proved to be useful for short-term storage of fruits and vegetables in hot and dry regions 1 . It has been extensively used for enhancing the shelf-life of horticultural...

Maize (Zea mays L.) is one of the most important nutritious grains which have high moisture content during harvest. Moisture content of 24-25% (db) at the harvest has to be reduced below 14% (db) to prevent its deterioration during storage. Drying process is generally performed by forced convection by heating ambient air and blowing it over grains to be dried. The aim of heating the air at certain temperature is to reduce the relative humidity of the air, which has a positive effect on the drying potential. In this study, drying behaviour of thin layer of maize for different drying air temperatures (40, 50, 60 and 70°C) and different air flow rates (20, 30 and 40) studied. The result shows that drying temperature has significant influence on a drying rate. With the increase in drying temperature drying rate increased. The moisture ratio reduced sharply up to 25 minutes of drying time, after that it decreased with drying time but at slower rate. In the beginning of the drying process, moisture transfer took place at faster rate than later. The effect of air flow rate on moisture content was found to be negligible except at the phase of drying. The analysis also illustrated that the drying of maize grains occurred during the falling rate period and no constant rate period was observed in this study. The drying rate constant was found to increase with increas in air temperature and was maximum for a combination of 700C air temperature and 40 air flow rate.

The small and marginal farmers in India are 83% with land holding of 46.1% and contribution of 51.2% in the production. On Indian farms, knapsack sprayers are very commonly used by small and marginal farmers for pest control because of affordability and ease of operation but with lower outputs. An attempt was made to develop a solar powered sprayer which had higher output (0.3 ha/hr) with lower physiological energy consumption and discomfort. An electronic control had been embedded for protection against deep discharge and over charging of battery for longer operational life. The system could be fully charged by solar energy within two hours of irradiation and can be operated continuously for six hours.This ensures quality spray with uniform droplet size in the swath. Anti-clogging filter had also been installed before the nozzle in nozzle head for trouble free operation as well as longer service life of nozzle.