Secondary Organic Aerosols from OH Oxidation of Cyclic Volatile Methyl Siloxanes as an Important Si Source in the Atmosphere

Cyclic volatile methyl siloxanes (cVMS) are active ingredients in widely used consumer products, which can volatilize into the atmosphere, thus attracting much attention due to their potential environmental risks. While in the atmosphere the cVMS undergo oxidation yielding both gaseous and particulate products. The aerosol yields and compositions from the OH oxidation of four cVMS (D3-D6) were determined under low and high-NOx conditions in an oxidation flow reactor. The aerosol yields progressively increased from D3 to D6, consistent with the volatilities and molecule weights of these cVMS. NOx can restrict the formation of SOA, leading to lower SOA yields under high-NOx conditions than under low-NOx conditions, with a yield decrease between 0.05–0.30 depending on the cVMS. Ammonium sulfate seeds exhibited minor impacts on SOA yields under low-NOx conditions, but significantly increased the SOA yields in the oxidation of D3-D5 at short photochemical ages under high-NOx conditions. The mass spectra of the SOA showed a dependence of its chemical compositions on OH exposure. At high exposures, equivalent to photochemical ages of > 6 days in the atmosphere, D4-D6 SOA mainly consisted of CxHy and CxHyOzSin under low-NOx conditions, whereas they primarily contained NmOz, CxHy, CxHyO1, CxHyO>1 and CxHyOzSin under high-NOx conditions. Using the yield data from the present study and reported cVMS annual production, a global cVMS-derived SOA source strength is estimated to be 0.16 Tg yr−1, distributed over major urban centers.

PENGARUH PROGRAM UPAYA KHUSUS (UPSUS) TERHADAP PRODUKTIVITAS, BIAYA POKOK PRODUKSI DAN PENDAPATAN USAHATANI PADI DI KABUPATEN PRINGSEWU

Rice is the staple food of Indonesian people. In 2014, its production was less than its need including its losses. Therefore, during 2015-2020, in order to increase the production through increasing its yield and its cropping intensity, the Ministry of Agriculture had been implementing the program of Upaya Khusus, called Upsus. The Upsus could be success if the farmers who participated in this program spent less the rice standard cost and obtained bigger profit. The question was whether the Upsus could increase yield, decrease standard cost and increase profit. Accordingly, the objective of this study was to answer this question. There were 30 respondents chosen by the simple random sampling method from six villages of three subdistricts. Each respondent was interviewed his farming budget in four seasons, i.e. rainy season 2014/2015, dry season 2015, rainy season 2017/2018, and dry season 2018. Consequently, the number of observation was 120. The data farming budget were used for getting the three following variables, i.e. yield (ton/ha), production standard cost (Rp/kg), and profit (Rp million/ha). The data were analyzed by using three multiple regression models. This study revealed that the Upsus was statistically significant on increasing its yield, decreasing its standard cost and increasing its profit. By implementing the Upsus, the increment in yield and profit of rice farming were 3 percent and 30 percent, respectively. The decrease in standard cost was 6 percent. The average yield, the standard cost and the profit of rice farming in Upsus were as follows 5,20 ton/ha, Rp4.154,-/kg and Rp6,82 million/haKeywords: profit, standard cost, upsus, yield

Comparison of aerobic rice cultivation using drip systems with conventional flooding

In this study, yield and water productivity response of rice to various irrigation levels applied with subsurface and surface drip systems in 2019 and 2020 in the Mediterranean Region of Turkey was evaluated in comparison with conventional flooding (CF). The treatments consisted of two irrigation methods namely surface drip (DI) and subsurface drip systems (SDI), three irrigation levels designated as plant pan coefficients (I1.00: Evaporation from Class A pan (Ep) × 1.00; I1.25: Ep × 1.25 and I1.50: Ep × 1.50) and CF as control. The effects of drip systems and coefficients on yield and yield components were statistically significant (P < 0.01). DI produced higher yield than SDI. CF produced significantly greater yield than both DI and SDI systems. With two drip systems, average water savings of 60.5% in I1.00, 54.5% in I1.25 and 49% in I1.50 were achieved as compared to CF. However, yield reductions of 15% in I1.50, 20% in I1.25, 29% in I1.00 were observed for DI; corresponding values for SDI were 20, 28 and 44%, respectively. Drip irrigation in aerobic rice production system had almost twice the water productivity based on total irrigation water applied (WPI) or total water input (irrigation + rainfall) (WPI+P) compared with CF. During the study years, the highest WPI and WPI+P values were found in DI-I1.00 (0.81–0.73 kg/m3) and (0.85 and 0.74 kg/m3), respectively. In conclusion, DI-I1.50 treatment is recommended for sustainable aerobic rice production since DI-I1.50 resulted in water saving of 49% but yield decrease of 15% as compared to CF.

Physiological and Biochemical Response to Fusarium culmorum Infection in Three Durum Wheat Genotypes at Seedling and Full Anthesis Stage

Fusarium culmorum is a worldwide, soil-borne plant pathogen. It causes diseases of cereals, reduces their yield, and fills the grain with toxins. The main direction of modern breeding is to select wheat genotypes the most resistant to Fusarium diseases. This study uses seedlings and plants at the anthesis stage to analyze total soluble carbohydrates, total and cell-wall bound phenolics, chlorophyll content, antioxidant activity, hydrogen peroxide content, mycotoxin accumulation, visual symptoms of the disease, and Fusarium head blight index (FHBi). These results determine the resistance of three durum wheat accessions. We identify physiological or biochemical markers of durum wheat resistance to F. culmorum. Our results confirm correlations between FHBi and mycotoxin accumulation in the grain, which results in grain yield decrease. The degree of spike infection (FHBi) may indicate accumulation mainly of deoxynivalenol and nivalenol in the grain. High catalase activity in the infected leaves could be considered a biochemical marker of durum sensitivity to this fungus. These findings allowed us to formulate a strategy for rapid evaluation of the disease severity and the selection of plants with higher level, or resistance to F. culmorum infection.

The Effects of Nutrient Solution Feeding Regime on Yield, Mineral Profile, and Phytochemical Composition of Spinach Microgreens

Microgreens are receiving increasing popularity as functional and healthy foods due to their nutritional value and high content of bioactive compounds. The aim of the present study was to evaluate the effects of nutrient deprivation through the regulation of nutrient solution (NS) feeding days on the plant growth and chemical composition of spinach microgreens. For this purpose, spinach microgreens were subjected to four different fertigation treatments—namely, 0 (control), 5, 10, and 20 NS feeding days before harvesting—and harvested tissues were evaluated with regard to fresh and dry yield, color of true leaves, antioxidant activity, and chlorophyll, carotenoid, and phenolic compound contents. The results of our study revealed that prolonged NS feeding (20 NS) resulted in the highest fresh yield and photosynthetic pigment contents (chlorophylls, lutein, and β-carotene). In contrast, mineral concentrations (P, K, Ca, and Mg) were the lowest for the 20 NS, whereas the control (0 NS) and 5 NS recorded the highest concentrations. Apart from that, spinach microgreens subjected to 10 NS treatment recorded 70.7% less nitrates, better mineral concentrations, 7.0% higher total ascorbic acid, similar polyphenol contents, higher DM%, and only 12.6% yield decrease compared to 20 NS treatment. In conclusion, although the highest overall fresh yield was recorded with the 20 NS treatment, the highest nitrate concentrations and the lowest mineral concentrations may raise food safety concerns. On the other hand, 10 NS treatment seems to be the most promising, since it combined high yields with high mineral concentrations and low nitrate concentrations, without compromising bioactive compound (e.g., polyphenols) contents, presenting a cost-effective and sustainable practice for microgreen cultivation.

Action and Reaction of Plants to High Temperature: Improving Response of Wheat to Heat Stress

All estimates suggest that by 2050, upto 50% increase in food production will be required to feed the world population. Wheat is the second most important crop after rice and by 2050, wheat production needs to be increased by 60% for socio-economic stability. However, the climate change induced global warming will have adverse effect on crop plants including wheat. To deal with the crop yield decrease influenced by global warming, an indepth study of heat induced morpho-physiological and molecular changes in wheat will result in better understanding of the plant. This review focuses on the impact of high temperature on the morphological, physiological, reproductive development and signaling in plants.

EVALUATION OF SOYBEAN VARIETIES FOR RESISTANCE OF AGROCENOSES TO COTTON BUDWORM (HELICOVERPA ARMIGERA) IN SAMARA REGION

Samer-2 is an undoubted leader in terms of attractiveness as a feed plant both in particular years and on average during the study years. A lower pest population, even in a year with a high number of pests, was shown by Cordoba variety. The rest of the studied varieties can be attributed to medium level of feed preference for cotton budworm. The observed pattern can presumably be explained by the difference in chemical composition of different varieties of soybean, which should be confirmed by further research, as well as by density of soybean plants. The best varieties in terms of protein content in our studies were Prudence, Alaska and Protina; the latter variety does not consistently accumulate this protein, which depends on weather conditions and other factors. The lowest grain moisture was shown by Alaska soybean variety, the agrocenosis of which had a low plant density. And conversely, the wettest grain had Samer-2 variety with a high number of plants per 1 m2. On average, over three years of observation, the best and consistently high yield was shown by Cordoba variety, due to, for one of the reasons, high resistance to damage by the cotton budworm. An opposite situation was observed for Protina and Samer-2 variants, a significant number of caterpillars of the studied phytophage led to a substantial yield decrease of these varieties, especially in the year favorable for development of this pest. Prudence and Alaska variants can be classified as medium-suppressed varieties with medium yields. To obtain a stable phytosanitary situation and obtain high-quality soybean crop, it is more expedient to cultivate Cordoba (high-yield) and Prudence (high-protein) varieties, with application of Biosleep BV, Zh insecticide (4 l / ha) for effective protection against cotton budworm.

One-pot synthesis of Ag–Cu–Cu2O/C nanocomposites derived from a metal–organic framework as a photocatalyst for borylation of aryl halide

Ag–Cu–Cu2O/C nanocomposites derived from metal–organic framework through one-pot thermal reduction method were synthesized. The material exhibits high catalytic activity in the borylation of aryl halide under xenon lamp condition across 7 cycles, with no yield decrease.

Response of spring wheat grown in drought stress to foliar and soil silicon application

The aim of study was the evaluation of silicon (Si) foliar and soil application effect on mitigation of drought stress in spring wheat. Twoyears study was performed in greenhouse with the use of vases with a capacity of 10 kg of soil. Silicon was used as a foliar application at the concentration of 6 mM Si/l and as soil application before plant sowing at doses 200 and 400 mg Si/kg, in the form of Na2SiO3. At the growth stage of tillering, drought stress was introduced and soil moisture was kept at 30% PPW. Silicon application positively affected yield and biochemical parameters of plants growing under water stress. Soil application was more efficient than foliar one in reducing of yield decrease and negative impact of water deficit on plants. Silicon uptake from soil by wheat was greater than from foliar application.