Água aquecida e radiação UV-C no controle pós-colheita de Cryptosporiopsis perennans em maçãs Heated water and UV-C radiation to postharvest control of Cryptosporiopsis perennans on apples

O objetivo deste trabalho foi avaliar a colonização de Cryptosporiopsis perennans na epiderme de maçãs e a eficiência da aplicação de água aquecida e radiação UV-C no controle desse patógeno. Em maçãs submetidas à inoculação de C. perennans, a colonização de lenticelas e das áreas adjacentes pelo patógeno foi avaliada por microscopia eletrônica de varredura. A sensibilidade dos conídios de C. perennans aos tratamentos foi avaliada em suspensão aquosa, às temperaturas de 28, 45, 50 e 55ºC, por 15 e 30 s, e às doses de radiação UV-C de 0,018, 0,037, 0,075, 0,150, 0,375, 0,750, 1,500 e 3,000 kJ m-2. Em maçãs submetidas à inoculação de C. perennans, foram avaliados os efeitos de 0,375, 0,750 e 1,500 kJ m-2 de radiação UV-C e da aspersão de água aquecida à 50ºC, por 15 e 30 s no controle do patógeno. O fungo produziu abundante micélio e conídios nas lenticelas e nas áreas adjacentes, na epiderme das maçãs. A água aquecida a 50ºC por 15 s e à dose de radiação de UV-C de 0,750 kJ m-2 reduzem em mais de 99% a sobrevivência de conídios. A aspersão de água aquecida a 50ºC por 15 s e à dose de radiação de UV-C de 0,375 kJ m-2, controlam C. perennans em maçãs.<br>The objective of this work was to assess the colonization of Cryptosporiopsis perennans in the epidermis of apples and the efficiency of heated water and UV-C radiation application to control this pathogen. In apples inoculated with C. perennans, the colonization of lenticels and adjacent areas by the pathogen was observed by electronic scanning microscopy. The sensitivity of C. perennans conidia was evaluated in aqueous suspension, at temperatures of 28, 45, 50 and 55ºC for 15 and 30 s, and at UV-C radiation doses of 0.018, 0.037, 0.075, 0.150, 0.375, 0.750, 1.500 and 3.000 kJ m-2. The effects of UV-C radiation doses at 0.375, 0.750 and 1.500 kJ m-2 and heated water at 50ºC, sprayed during 15 and 30 s were evaluated for controlling C. perennans in apples inoculated with the pathogen. The fungus produced abundant mycelium and conidia in lenticels and adjacent areas on the epidermis of the apples. The heated water at 50ºC during 15 s and a 0.750 kJ m-2 UV-C radiation dose reduced conidia survival in more than 99%. Heated water sprayed at 50ºC during 15 s and a UV-C radiation dose of 0.375 kJ m-2 control C. perennans in apples

The Core Mass Function in the Orion Nebula Cluster Region: What Determines the Final Stellar Masses?

Applying dendrogram analysis to the CARMA-NRO C18O (J = 1-0) data having an angular resolution of ∼8″, we identified 692 dense cores in the Orion Nebula Cluster region. Using this core sample, we compare the core and initial stellar mass functions in the same area to quantify the step from cores to stars. About 22% of the identified cores are gravitationally bound. The derived core mass function (CMF) for starless cores has a slope similar to Salpeter's stellar initial mass function (IMF) for the mass range above 1 M o˙, consistent with previous studies. Our CMF has a peak at a subsolar mass of ∼0.1 M o˙, which is comparable to the peak mass of the IMF derived in the same area. We also find that the current star formation rate is consistent with the picture in which stars are born only from self-gravitating starless cores. However, the cores must gain additional gas from the surroundings to reproduce the current IMF (e.g., its slope and peak mass), because the core mass cannot be accreted onto the star with 100% efficiency. Thus, the mass accretion from the surroundings may play a crucial role in determining the final stellar masses of stars. © 2021. The American Astronomical Society. All rights reserved..Immediate accessThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]