Abstract
One of the main challenges in castor crop (Ricinus communis L.) production is efficient weed management mainly due to limited options of selective herbicides. This study evaluated the selectivity of herbicides applied alone or in combination in pre- and postemergence applications in castor crop. Two field experiments were carried out under irrigation conditions in a semi-arid region of Northeast Brazil. It was found that the visual symptoms of phytointoxication of the herbicides used on castor were mild in both experiments. Consequently, there were no significant interferences on plant height, number of racemes, and grain (seed) yield. Pre-emergence applications (g ha−1) of trifluralin (1800), pendimethalin (1500), clomazone (750), clomazone + trifluralin (750 + 1800), and clomazone + pendimethalin (750 + 1500) followed by chlorimuron-ethyl in postemergence (15 g ha−1) are selective to castor. The application (g ha−1) of pendimethalin + clomazone (1000 + 500) in pre-emergence, associated with chlorimuron-ethyl (10 and 15), metamitron (2800 and 4200), ethoxysulfuron (60 and 80), or halosulfuron-methyl (75 and 112.5) in one or two applications in postemergence, as single or split applications, in an interval of 14 days, are selective to castor crop.
Highlights
Castor oil is widely used in the industry for containing ricinoleic acid and unique properties in its fatty acids, being a valuable input for the production of lubricants, paints, plastics, drugs, and cosmetics [1,2]
Very mild symptoms of phytointoxication were observed on castor plants twenty days after the pre-emergence application, characterized by only chlorosis of some leaves on castor plants, except for treatment with trifluralin (1800 g ha−1) where there were no symptoms of visual injuries (Table 1)
Clomazone applied at a dose of 750 g ha−1 or in a tank mixture with trifluralin (1800 g ha−1) and pendimethalin (1500 g ha−1) resulted in phytointoxication symptoms significantly higher than the other treatments
Summary
Castor oil is widely used in the industry for containing ricinoleic acid and unique properties in its fatty acids, being a valuable input for the production of lubricants, paints, plastics, drugs, and cosmetics [1,2]. The growth in world consumption has been limited by low agricultural production capacity, with great potential for expanding the cultivated area and increasing productivity [3,4]. Brazil’s productivity is considered extremely low, demanding the improvement of their production systems to allow further expansion of cultivated area with that crop. In this scenario, coupled with the development of more productive and precocious recent genetic materials and the development of mechanized harvesting, castor bean cultivation has shown potential to regions of higher technological level, such as the Brazilian cerrado, as an alternative rotation and succession (second harvest) to soybean, cotton, and corn cultivation [6]
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 callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
