Rising temperature affects agricultural production, causing food insecurity. Thus, the objective of this study was to evaluate how increased temperature influences pollen viability, photosynthetic and enzymatic responses, and their consequences on the final yield of cowpea cultivars. The cultivars BRS Acauã, BRS Guariba, BRS Gurguéia, and BRS Pajeú were used, kept in growth chambers under two temperature regimes: 24.8–30.8–37.8 °C and 20–26–33 °C. The cultivars BRS Acauã, BRS Guariba, and BRS Pajeú showed prolonged flowering and greater flower abortion, at 23.58%, 34.71%, and 25.55%, respectively, under an increase of 4.8 °C in temperature. This increase also reduced the viability of BRS Acauã and BRS Pajeú pollen by 34 and 7%, respectively. Heating increased stomatal opening and transpiration but reduced chlorophyll content. The enzymatic response varied according to cultivars and temperature. Changes in photosynthetic and enzymatic activities contribute to reducing pollen viability and productivity. BRS Acauã was the most affected, with an 82% reduction in the number of seeds and a 70% reduction in production. BRS Gurguéia maintained its production, even with an increase of 4.8 °C, and can be selected as a cultivar with the potential to tolerate high temperatures as it maintained pollen viability, with less flower abortion, with the synchrony of physiological and biochemical responses and, consequently, greater production.

Selecting genotypes tolerant to high temperatures is an important measure for agricultural maintenance and production in climate change scenarios. Thus, this study aimed to select cowpea genotypes tolerant to increased air temperature. A total of 20 cowpea genotypes were used, cultivated under temperature regimes of 20–26–33 °C and 24.8–30.8–37.8 °C in a completely randomized experimental design under a 2 × 20 factorial scheme (temperature regimes × genotypes). The BRS Inhuma, Bico-de-Ouro-17-45, BRS Guariba, and BRS Imponente genotypes did not show significant differences in the analyzed physiological responses to the increase in air temperature. The BRS Inhuma, Bico-de-Oouro-17-19, Bico-de-Ouro-17-44, Bico-de-Ouro-17-45, BRS Guariba, and BRS Imponente genotypes showed increased temperature tolerance as thermal stress did not affect production. The Pingo-de-Ouro-17-48, MNC00-595F-27, MNC06-895E-1, and MNC09-981B-2 genotypes reduced water efficiency by −26.85, −25.19, −40.04, and −60.37%, respectively, due to the increase in temperature. The results obtained in this work represent a pre-selection of genotypes that are tolerant to high temperatures, with the BRS Inhuma, Bico-de-Ouro-17-45, BRS Guariba, and BRS Imponente genotypes indicated as tolerant to increased temperatures based on the interaction of physiological and productive responses. There is an urgent need to select cowpea genotypes tolerant to increased temperature to maintain production in climate change scenarios and ensure agricultural systems’ sustainability and food security.

The impact of climate on sorghum cultivation, generated mainly by scenarios of increased temperature, can affect plant development and cause losses in crop yield. Thus, the objective of this work was to select sorghum cultivars tolerant to high temperatures, through the evaluation of biometric, enzymatic, and productive parameters. The experiment was carried out in growth chambers, with seven sorghum cultivars (AGRI-002E, BRS 506, BRS 716, SF 15, IAC Santa Elisa, BRS Ponta Negra, and Volumax) and four temperature regimes (20.0-26, 0-33.0°C; 24.8-30.8-37.8°C; 26.3-32.3-39.3°C and 27.8-33.8-40.8°C), in a completely randomized design, with four replications. The biometric and productive parameters and activity of the enzymes superoxide dismutase, catalase, and ascorbate peroxidase were evaluated. The cultivars AGRI-002E, BRS 506, BRS Ponta Negra, and Volumax showed better defense of the antioxidant system with increasing air temperature, with less accumulation of reactive oxygen species and greater biomass production. These cultivars can be classified as tolerant to an increase of up to 6.3 °C in air temperature, with emphasis on cultivar BRS 506, which showed higher production of stem dry mass.

Condições ambientais adversas, como o aumento da temperatura do ar, tem impacto sobre o crescimento inicial das plantas, interferindo no potencial de rendimento dos cultivos. Assim, objetivou-se avaliar o efeito do aumento da temperatura no estabelecimento inicial de plantas de mandioca. O experimento foi realizado em câmaras de crescimento, com delineamento inteiramente casualizado em esquema fatorial 3x2 (cultivares x regimes de temperatura), com cinco repetições, durante 165 dias. Foram utilizadas mudas de mandioca das cultivares BRS 417, BRS 420 e BRS CS01 e os regimes de temperatura: T1 (20-26-33 °C) e T2 (24.8-30.8-37.8 °C). Os parâmetros fisiológicos foram afetados negativamente pelo aumento da temperatura. Essas alterações fisiológicas resultaram no aumento da temperatura foliar. A cultivar BRS 420 apresentou maior diâmetro do caule, quando comparada às demais, com uma média de 4,63 mm. O regime de temperatura de 24.8-30.8-37.8 °C contribuiu para maior altura das plantas das cultivares BRS 420 e BRS CS01, com média de 104.28 e 89.54 cm respectivamente. O aumento da temperatura também contribuiu para maior produção de biomassa da parte aérea, com um aumento de massa fresca de 41% e 52% e massa seca de 20% e 37% para BRS 420 e BRS CS01, respectivamente. A massa fresca do sistema radicular foi maior com o aumento da temperatura para as três cultivares analisadas, com destaque para BRS 420, que também apresentou maior produção de massa seca das raízes, independentemente do regime de temperatura. O aumento da temperatura do ar, com regime diário de 24.8-30.8-37.8 °C favoreceu o crescimento e desenvolvimento das plantas jovens de mandioca, contribuindo para o seu estabelecimento, mesmo com alterações nas respostas fisiológicas.