de Abreu Deivisson Pelegrino, Roda Newton de Matos, de Abreu Gideao Pelegrino, Bernado Wallace de Paula, Rodrigues Weverton Pereira, Campostrini Eliemar, Rakocevic Miroslava
Laboratory for Plant Genetic Breeding (LMGV), State University of the North Fluminense Darcy Ribeiro, Rio de Janeiro, Brazil.
Department of Exact, Environmental and Technological Sciences (CEATEC), Pontifical Catholic University of Campinas, Campinas, Brazil.
Front Plant Sci. 2022 Jan 7;12:784482. doi: 10.3389/fpls.2021.784482. eCollection 2021.
Increases in water use efficiency (WUE) and the reduction of negative impacts of high temperatures associated with high solar radiation are being achieved with the application of fine particle film of calcined and purified kaolin (KF) on the leaves and fruits of various plant species. KF was applied on young and plants before their transition from nursery to full sunlight during autumn and summer. The effects of KF were evaluated through the responses of leaf temperature (T), net CO assimilation rate (), stomatal conductance ( ), transpiration (), WUE, crop water stress index (CWSI), index of relative stomatal conductance (I), initial fluorescence (F), and photosynthetic index (PI) in the first 2-3 weeks after the plant transitions to the full sun. All measurements were performed at midday. In plants, KF decreased the T up to 6.7°C/5.6°C and reduced the CWSI. The plants that were not protected with KF showed lower , , , and I than those protected with KF. plants protected with KF achieved higher WUE compared with those not protected by 11.23% in autumn and 95.58% in summer. In both sp., KF application reduced F, indicating reduced physical dissociation of the PSII reaction centers from the light-harvesting system, which was supported with increased PI. The use of KF can be recommended as a management strategy in the transition of seedlings from the nursery shade to the full sunlight, to protect leaves against the excessive solar radiation and high temperatures, especially in during the summer.
通过在各种植物的叶片和果实上喷施煅烧提纯高岭土微粒膜（KF），可提高水分利用效率（WUE），并减轻与高太阳辐射相关的高温负面影响。在夏秋季节，当幼苗从苗圃过渡到全日照之前，对幼苗喷施KF。通过植物过渡到全日照后的前2至3周内，叶片温度（T）、净CO2同化率（ ）、气孔导度（ ）、蒸腾作用（ ）、WUE、作物水分胁迫指数（CWSI）、相对气孔导度指数（I）、初始荧光（F）和光合指数（PI）的响应来评估KF的效果。所有测量均在中午进行。在 植物中，KF使T降低了6.7°C/5.6°C，并降低了CWSI。未喷施KF保护的植物的 、 、 和I均低于喷施KF保护的植物。喷施KF保护的 植物在秋季和夏季的WUE分别比未保护的植物高11.23%和95.58%。在两种 植物中，喷施KF均降低了F，表明PSII反应中心与光捕获系统的物理解离减少，这一点得到了PI增加的支持。在 幼苗从苗圃遮荫过渡到全日照的过程中，推荐使用KF作为一种管理策略，以保护叶片免受过多太阳辐射和高温的影响，尤其是在夏季的 。
