Abstract
ABSTRACT The objective of this study was to determine the photochemical efficiency of ‘Gigante’ cactus pear cultivated under different spacings and bovine manure doses in the semi-arid region. The experiment was conducted in a randomized block design in a 4 x 3 x 7 factorial scheme, with three replicates. The first factor consisted of four doses of organic fertilization (0, 30, 60 and 90 Mg ha-1 year-1 of bovine manure), the second one, of three spacings (1.0 x 0.5, 2.0 x 0.25 and 3.0 x 1.0 x 0.25 m) and the third one of seven reading times (6, 8, 10, 12, 14, 16 and 18 h). Chlorophyll a fluorescence readings were taken in cactus pear cladodes in the dry and rainy seasons using a pulse-modulated fluorometer. Cladodes of ‘Gigante’ cactus pear cultivated under different spacings and bovine manure doses undergo changes in photosystem II during the dry season under the physiographic conditions of the semi-arid region in Bahia. During the rainy season in the semi-arid region, the photosynthetic yield in cactus pear cladodes is considered ideal.
Highlights
Cactus pear (Opuntia ficus-indica) is used as animal feed in production systems of various arid and semi-arid regions worldwide (Grünwaldt et al, 2015), for having features of coexistence with the environmental limitations present in these regions, such as stress by water deficit, high temperatures and excess radiation (Donato et al, 2014).Cactus pear is a xerophile plant and its physiology is characterized by the photosynthetic process called Crassulacean acid metabolism (CAM) and, under stress conditions, water is saved due to stomatal closure during the day and opening during the night with CO2 fixation
The objective was to determine the photochemical efficiency of ‘Gigante’ cactus pear cultivated under different spacings and bovine manure doses in the semi-arid region
The parameters of chlorophyll a fluorescence evaluated in cladodes of ‘Gigante’ cactus pear during July-August, dry season, varied according to the reading times, regardless of spacing and organic fertilization (Table 2), except for maximum fluorescence (Fm), variable fluorescence (Fv) and quantum efficiency (Fv/Fm)
Summary
Cactus pear (Opuntia ficus-indica) is used as animal feed in production systems of various arid and semi-arid regions worldwide (Grünwaldt et al, 2015), for having features of coexistence with the environmental limitations present in these regions, such as stress by water deficit, high temperatures and excess radiation (Donato et al, 2014).Cactus pear is a xerophile plant and its physiology is characterized by the photosynthetic process called Crassulacean acid metabolism (CAM) and, under stress conditions, water is saved due to stomatal closure during the day and opening during the night with CO2 fixation. Chlorophyll a fluorescence has allowed inferences on the efficiency of the photochemical phase of photosynthesis and can be useful in studies on the physiological behavior of CAM plants (Romo-Campos et al, 2013; Cruz et al, 2014; Díez et al, 2017). It can help understand the adaptability and resistance to drought of cactus pear in the soil-plantatmosphere production context of the semi-arid region. Studies on physiology are still scarce (Adams Terceiro et al, 1989; Winter & Lesch, 1992; Becerril & Valdivia, 2006) and are necessary to fill these gaps in the knowledge on the crop
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
