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Pesticide drift is due to the transport of the active ingredient to areas not targeted by spraying, causing negative effects on the sensitive crops' development. The aim of this study was to evaluate lettuce response to simulated 2,4-D drift. Experiments were conducted in the greenhouse, in a randomized complete block design with four replications. The treatments consisted of nine different doses of the 2,4-D herbicide, which are: 0; 1.56; 3.125; 6.20; 12.5; 25; 50; 75; and 100% from the recommended dose (670 g a.a. ha-1). The application occurred when the lettuce plants had four to six true leaves. The analyzed variables were visual injury (phytotoxicity), development parameter (phyllochron), growth (rosette diameter and dry mass of the aerial part), and photosynthetic parameters (gas exchange). The lettuce crop showed high sensitivity to the 2,4-D herbicide, with the lowest dose resulting in significant phytotoxic damage to plants, and from 12.5% of the recommended 2,4-D dose, visual injuries were greater than 90%. The plants' development and growth were negatively affected by the increased drift doses, culminating in enhanced phyllochron and reduction in rosette diameter and dry mass of the aerial part. The gas exchange of the crop was affected from 6.20% of the recommended dose, causing a reduction in the CO2 assimilation rate, stomatal conductance, transpiration rate and rubisco carboxylation efficiency. [ABSTRACT FROM AUTHOR]

Statice is an important cut flower belonging to the Plumbaginaceae family and which has good acceptance among producers and consumers. The construction of a phenological scale for statice that is easy, fast, and non‐destructive can contribute to the improvement of management practices, increase flower yield and quality, increase the knowledge on the plant and facilitate the communication between the scientific and technical personnel. Field and greenhouse experiments with seven sowing dates were carried out during 2019 and 2020 at the Universidade Federal de Santa Maria, in Santa Maria, RS, Brazil, with Assorted Seeds (mix) and two cultivars (QIS Purple and QIS Yellow) of statice to describe the main stages of plant development. The developmental cycle of statice was divided into three phases: germination, vegetative and reproductive. The germination phase includes the stages S0, S1, S2 and SE, the vegetative phase comprises the stages VC, V2, V8, V10, V20, V100 and Vn, and the reproductive phase has the stages R1, R1.1, R1.2, R1.n, R2, R2.1, R2.2, R2.n, R3, R3.1, R3.2, R3.n, R4, R4.1, R4.2, R4.n, R5, R5.1, R5.2, R5.n, R6, R6.1, R6.2, R6.n, R7, R7.1, R7.2, R7.n, R8, R8.1, R8.2, R8.n and R9. Part of the vegetative development overlaps the reproductive development to represent the appearance of new leaves as new floral stems develop. The phenological scale proposed for statice has practical applications and can be easily used in the field by scientists, teachers, students, consultants and farmers. [ABSTRACT FROM AUTHOR]

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