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Tomato (Solanum lycopersicum L., family Solanaceae) represents one of the most cultivated horticultural crops worldwide. It contains various nutrients, providing health benefits. For better crop management strategies, especially with global warming, it is crucial to investigate how varieties or cultivars bred for different purposes respond to the changing macro or microenvironmental conditions. This research aimed to assess the growth, reproductive development and selected quality parameters of two tomato varieties, 'Sylviana' (a greenhouse hybrid) and 'Bolseno' (a dual-purpose variety), under a greenhouse environment. The study was conducted in the mid-country wet zone of Sri Lanka where the intensive-control greenhouse (T1) maintained a favourable air temperature (<33°C) for crop growth compared to high daytime temperatures of semi-intensive (T2) and less-intensive (T3) greenhouses (up to 36°C). In 'Bolseno', vegetative growth parameters were significantly affected (P<0.05) by different environments but not in 'Sylviana' (P>0.05). T1 resulted in the highest mean fruit weight and mean fruit diameter in both varieties. Since 'Sylviana' performed well in all three growing environments, the fruit quality was assessed by measuring the antioxidant activity (AOX) and total phenolic content (TPC) using 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay and Folin-Ciocalteu method, respectively. Significantly higher AOX (P<0.05) was reported in T1 while T2 had a higher TPC. The results revealed that different tomato genotypes respond differently to changes in micro environmental conditions in terms of growth and some reproductive traits, and the same variety grown in different conditions had different TPC and AOX. [ABSTRACT FROM AUTHOR]

Heat pump drying systems require a method to change the inflow air temperature of the drying chamber. Pulse-widthmodulation (PWM) technique with duty cycle provides a measure of controlling the voltage supplied to the electric motors. Therefore, we conducted this research to PWM control a heat pump dryer to change the air circuit parameters. In the Parallel-Flow condensers, inlet and outlet temperatures, and relative humidity, data were collected, and the average temperature values were recorded. The duty cycle was changed by developing a program using the Python programming language. An Excel-based psychrometric calculator was developed to analyze the collected data. The average condenser outlet temperatures were 56.6±0.1 °C, 54.9±0.1 °C, and 52.6±0.1°C, and the average condenser inlet temperatures were 43.2±0.0 °C, 42.8±0.1 °C, and 41.2±0.1 °C for 60%, 80%, and 100% duty cycles, respectively. The power consumption rate of the condenser reduced with an increasing duty cycle. The results concluded that the PWM control system is a viable method to control the inflow air temperature to the drying chamber. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the effect of milling conditions on milling quality of medium grain rough rice M202. Using a McGill No. 3 mill, the conditions studied were milling weight and duration, and polishing weight and duration. This research examined the relationships among the milled rice quality parameters, namely total rice yield, head rice yield, whiteness index, and total lipid content. Head rice yield was more sensitive to changes in milling conditions than total rice yield. It decreased by 4.6 percentage points when milling weight was increased from 2. 72 to 6.36 kg. Milling weight and milling duration had more influence on head rice yield than polishing weight and duration. For both milling and polishing, using lower weights for a longer duration could increase head rice yield without changing the whiteness compared to the standard procedures of the USDA Federal Grain Inspection Service. The total lipid content of milled rice, measured using a near-infrared (NIR) method, correlated well with the whiteness index. This indicates that the NIR method could be used as an alternative to the whiteness index for measuring the degree of milling. Over-milling significantly decreased head rice yield with little improvement in whiteness. The milling quality of M202 can be predicted by using the developed non-linear regression models when the milling and polishing conditions are known. [ABSTRACT FROM AUTHOR]