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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.

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...

This research study was envisaged to evaluate the effect of parameters, viz. initial germination percentage (IGP), soaking duration (SD), temperature, rotation speed (rpm) and air flow rate (AFR) for hydropriming of Okra (Abelmoschus esculentus L.) seeds. Three different seed lots based on their moisture content and germination percentage were chosen in this study. Moisture content and germination percentage of the selected lots varied from 11.33 to 16.89% (d.b.) and 50 to 80%, respectively. Accelerated ageing was performed at 40 ± 1°C, 100% relative humidity to obtain required lots from available seed sample. Response surface methodology was adopted using a five factor three-level Box-Behnken design with soaking duration (4, 5 and 6 h), temperature (20, 25, 30°C), rotation speed, (320, 340, 360 rpm), air flow rate, (2.192, 2.740, 3.288 m 3 /min) as the main process parameters. The effect of process affecting parameters was observed on responses, viz. moisture content, germination percentage, seedling length, seedling dry weight, vigour index-I, vigour index-II, electrical conductivity and radiography. Models were found to be significant for all the process responses with the optimal solution as 73% (IGP), 6 h (SD), 23°C temperature, 330 (rpm) and 2.50 m 3 /min (AFR).

Rough rice is typically harvested at moisture contents ranging from 20% to 24%, and subsequently dried to approximately 12% for safe long‐term storage and milling. Harvesting paddy at high moisture content normally results in high yields and less damage and prevents field losses due to dropping and shattering. Drying of grains creates moisture and temperature gradient within the kernel resulting in the development of tensile stresses at the surface and compressive stress at the interior of the rice kernel. These stresses may result in kernel fissuring and subsequent breakage during milling. Thus, drying is considered to be one of the most critical operations in post‐harvest processing of paddy which has great influence on milling yield. Basmati rice possesses unique cooking, eating and digestive qualities. India accounts for more than 70% of the world basmati rice production. Among basmati, PB1121 is widely grown in India and contributes a major share of rice exports from the country. Therefore drying of PB1121 was carried out with the objective to optimize the drying variables for minimum drying time and maximum head yield. Drying was carried out in 2‐passes using a cross‐flow dryer. The drying experiment in thin layer was conducted as per a central composite rotatable design in response surface methodology with 3 factors (drying air temperature, tempering time and moisture reduction in first drying pass) at 5 levels. The variables chosen for the experiment were drying air temperature (40–70 °C), tempering time (60–240 min) and moisture reduction percentage (3–10%) in the first pass of drying. Optimization of drying variables was done through the use of a desirability function by combining all responses into one measurement. The desirability functions were minimum drying time, maximum brown rice yield and head rice yield. Total drying time ranged from 35 to 132 min in two stages of drying, while in continuous drying it varied from 41 to 204 min. Head rice yield ranged from 39.77 to 71.56%. Optimum conditions for drying of paddy grains were found to be temperature of 58.3 °C, 7.13% moisture reduction and 148 min tempering time. At optimized conditions, total drying time and head rice yield were calculated at 53.1 min and 54.53%, respectively.

India is the second-largest producer of vegetables. However, vegetables are critical for storage, due to their highly perishable nature, lack of cold storage and transportation facilities. Vegetables get shrivel, whither rapidly, especially under hot conditions, if not preserved just after harvest. The study was conducted at ICAR-IARI to access the effect of abiotic parameters on vegetable quality with time. Effect of abiotic parameters on vegetable storability was studied and statistical analysed results revealed that there was a significant difference (P=0.05) in storage parameters occur when vegetables stored at different temperature and relative humidity. Storability parameters physiological loss in weight (PLW), firmness, colour values and total soluble solids (TSS) of vegetables tomato, spinach, and radish with different temperature and relative humidity were determined. The effect of abiotic parameter i.e. temperature and relative humidity on PLW physiological loss in weight was found significantly different at 5% level of significance. Temperature reduction of  5 – 10°C  and RH increment of 10% have a significant effect on quality parameters i.e. PLW, TSS, colour values of vegetables PLW of vegetables and TSS showed an increasing trend with an increase in temperature and decrease in relative humidity. The firmness of tomato and radish showed a decreasing trend with the increase in temperature and decrease in relative humidity but spinach firmness trend was found the opposite. Thus control over these abiotic parameters is essential to retain the quality of the vegetables and prevent their spoilage.