ALBERT

Description: The evolution of individual and total capsaicinoids content in three pepper varieties of Capsicum chinense Jacq. (‘Bode’ (B), ‘Habanero’ (H), and ‘Habanero Roxo’ (Hr)) during fruit ripening was studied. The five major capsaicinoids (nordihydrocapsaicin, capsaicin, dihydrocapsaicin, homocapsaicin, and homodihydrocapsaicin) were extracted using ultrasound-assisted extraction and the extracts were analysed by ultra-performance liquid chromatography with fluorescence detection (UHPLC-Fl). The plants were grown in a glasshouse and sampled every 7 days until over-ripening. As expected, the results indicated that the total capsaicinoids content increases during the ripening of pepper fruits. The maximum contents of capsaicinoids were reached at different fruit development stages depending on the cultivar. The ‘Habanero Roxo’ pepper presented the greatest total capsaicinoids content (3.86 mg g−1 fresh weigh, F.W.), followed by the ‘Habanero’ pepper (1.33 mg g−1 F.W.) and ‘Bode’ pepper (1.00 mg g−1 F.W.). In all the samples, capsaicin represented more than 80% of the total capsaicinoids content. Due to the high variability observed in the evolution of capsaicinoids content over the ripening process, this work intends to contribute to the existing knowledge on this aspect in relation to the quality of peppers.

Description: Agronomy, Vol. 7, Pages 74: Resistance to Wheat Curl Mite in Arthropod-Resistant Rye-Wheat Translocation Lines Agronomy doi: 10.3390/agronomy7040074 Authors: Lina Aguirre-Rojas Luaay Khalaf Sandra Garcés-Carrera Deepak Sinha Wen-Po Chuang C. Smith The wheat curl mite, Aceria toschiella (Keifer), and a complex of viruses vectored by A. toschiella substantially reduce wheat yields in every wheat-producing continent in the world. The development of A. toschiella-resistant wheat cultivars is a proven economically and ecologically viable method of controlling this pest. This study assessed A. toschiella resistance in wheat genotypes containing the H13, H21, H25, H26, H18 and Hdic genes for resistance to the Hessian fly, Mayetiola destructor (Say) and in 94M370 wheat, which contains the Dn7 gene for resistance to the Russian wheat aphid, Diuraphis noxia (Kurdjumov). A. toschiella populations produced on plants containing Dn7 and H21 were significantly lower than those on plants of the susceptible control and no different than those on the resistant control. Dn7 resistance to D. noxia and H21 resistance to M. destructor resulted from translocations of chromatin from rye into wheat (H21—2BS/2RL, Dn7—1BL/1RS). These results provide new wheat pest management information, indicating that Dn7 and H21 constitute resources that can be used to reduce yield losses caused by A. toschiella, M. destructor, D. noxia, and wheat streak mosaic virus infection by transferring multi-pest resistance to single sources of germplasm.

Description: Watermelon and melon crops are affected by some important soil-borne fungal diseases like carbonaceous rot (Macrophomina phaseolina), collapse (Monosporascus cannonballus), or the most important pathology at an economic level, the Fusarium wilt (Fusarium oxysporum f. sp. niveum, F. oxysporum f. sp. melonis, F. solani f. sp. cucurbitae, Neocosmospora falciformis, and N. keratoplastica). The methods commonly used for their control are often ineffective, thus new approaches, as the use of biological control agents, are constantly being sought. This work aimed to isolate, identify, and test endophytic fungi for their antagonistic properties against the three mentioned diseases. For this, about 350 endophytic fungal strains were isolated from asymptomatic watermelon plants. Among these, 7 fungal species were selected to evaluate their antagonistic potential against 14 pathogens. Dual culture assays allowed to select two Trichoderma strains according to the high inhibition rates observed (up to 93%), that were further employed in melon and watermelon plants, showing that some of the pathogens were controlled in terms of disease incidence, exhibiting a decrease up to 67% for T. lentiforme. In addition, three concentrations of Epicoccum purpurascens extract was selected to evaluate the germicide effect, obtaining significant differences in the growth of the pathogens depending on fermentation parameters.

Description: Interest in the consumption of the fruits of pepper (Capsicum spp.) is not only due to its organoleptic characteristics, but also due to its bioactive compounds content, which are reported to provide essential benefits to human health. However, the amount and diversity of these compounds in each fruit specimen depend on its genotype and on a number of environmental factors. This work describes the quantitative ultra-high-performance liquid chromatography coupled to photodiode-array (UHPLC-PDA) analysis of the capsinoids content in four varieties of pepper (‘Habanero’, ‘Habanero Roxo’, ‘Bode’, and ‘Malagueta’) grown until different development stages in a greenhouse under controlled conditions. In all the varieties analyzed, capsiate was the only capsinoid found. The accumulation of capsiate, in all the pepper varieties, started from the 10th to the 20th day post-anthesis (dpa), and increased during the first days (between the 20th and the 27th dpa). From that moment a drastic reduction took place until the end of the ripening stage, except for ‘Bode’ peppers, where the capsiate content increased from the first harvest point on the 20th dpa up to the 76th dpa. The capsiate accumulation patterns over the development of the fruit has been related to the capsaicionoids accumulation patterns in the same samples of the four varieties of pepper. According to our results, the content evolution of both families of compounds will vary depending on each fruit’s genotype, as well as on environmental conditions. No clear trends have been established and, therefore, an in-depth analysis under controlled conditions should be carried out.

Description: The evolution of individual and total capsaicinoids content in three pepper varieties of Capsicum chinense Jacq. (‘Bode’ (B), ‘Habanero’ (H), and ‘Habanero Roxo’ (Hr)) during fruit ripening was studied. The five major capsaicinoids (nordihydrocapsaicin, capsaicin, dihydrocapsaicin, homocapsaicin, and homodihydrocapsaicin) were extracted using ultrasound-assisted extraction and the extracts were analysed by ultra-performance liquid chromatography with fluorescence detection (UHPLC-Fl). The plants were grown in a glasshouse and sampled every 7 days until over-ripening. As expected, the results indicated that the total capsaicinoids content increases during the ripening of pepper fruits. The maximum contents of capsaicinoids were reached at different fruit development stages depending on the cultivar. The ‘Habanero Roxo’ pepper presented the greatest total capsaicinoids content (3.86 mg g−1 fresh weigh, F.W.), followed by the ‘Habanero’ pepper (1.33 mg g−1 F.W.) and ‘Bode’ pepper (1.00 mg g−1 F.W.). In all the samples, capsaicin represented more than 80% of the total capsaicinoids content. Due to the high variability observed in the evolution of capsaicinoids content over the ripening process, this work intends to contribute to the existing knowledge on this aspect in relation to the quality of peppers.

Description: “Naga Jolokia” (Capsicum chinense Jacq.) is a hot pepper variety native to India which has received the attention of the global scientific community due to its high capsaicinoid concentration. The present study evaluated the influence of fruit ripening on the total and individual capsaicinoids, as well as capsiate content. The aim was to determine the optimal moment to harvest the peppers depending on their pungent properties. Ultrasound-assisted extraction (UAE) using methanol as the extraction solvent and reverse-phase ultra-high-performance liquid chromatography (UHPLC-photodiode array (PDA)) were employed. Capsaicinoids gradually accumulated in the peppers from the moment they started growing until they reached a maximum concentration (7.99 ± 0.11 mg g−1 of fresh weight (FW)) at 33 days postanthesis (dpa). For this reason, based on its content of pungent compounds, as it is one of the main attributes of this variety, the optimal time for collection would be on day 33. From then on, there was a sharp decrease (96.35% of the total concentration) due to the peroxidase enzymes. The evolution of the principal capsaicinoids in “Naga Jolokia” peppers had a different behavior with respect to literature reports. After this investigation, these changes in content can be attributed to each pepper genotype. Capsiate content reached it maximum value at 19 dpa (0.27 ± 0.01 mg g−1 of FW). Then, there was a gradual drop due to the activities of different peroxidases. Given the important biological activity of capsaicinoids and capsinoids, the information described here allows for determining the ideal time to harvest “Naga Jolokia” peppers.