Abstract
Abstract The aim of this study was to evaluate some morphogenetic and structural characteristics to explain variations in forage accumulation of Alexandergrass (Urochloa (Syn. Brachiaria) plantaginea) under continuous stocking method. The experimental treatments consisted of four grazing heights (10, 20, 30, and 40 cm), allocated to experimental units following a randomized block design with three replicates. The following variables were analyzed: leaf appearance, elongation, and senescence rates, leaf lamina length, number of leaves per tiller, leaf area index (LAI), and forage accumulation rate. Data were submitted to analysis of variance and means were compared by Student's t-test (P≤0.05). The main results were: i) different grazing heights had different tissue flows; ii) grazing heights between 30-40 cm showed the highest LAI, and produced similar values; iii) forage accumulation rate increased according to grazing height increments, but did not change above 30 cm. In conclusion, Alexandergrass pastures under continuous stocking should not be maintained at grazing heights lower than 30 cm if the objective is to maximize forage production.
Highlights
The main results were: i) different grazing heights had different tissue flows; ii) grazing heights between 30-40 cm showed the highest Leaf area index (LAI), and produced similar values; iii) forage accumulation rate increased according to grazing height increments, but did not change above 30 cm
The leaf appearance rate (LAR) varied according to the evaluation period (P=0.0109) and the grazing height (P=0.0073), with no significant interaction between these factors (P=0.9124)
Regardless of the evaluation period, pastures maintained at more than 30 cm presented a lower LAR, though the 20 cm treatment was statistically equivalent (Table 1). Such a result can be attributed to the greater leaf sheath tube commonly observed at taller grazing heights, what leads to a delay in the emergence and visualization of subsequently appeared leaves[10]
Summary
In areas intended for integrated crop-livestock systems (ICLS), Alexandergrass can be a low-cost forage alternative, as it has a high potential for natural reseeding, and benefits from cultural practices (e.g., fertilization) that were performed in previous crops. Because it is present in large quantities at the end of the summer cropping season, it can be considered as a fodder alternative during the feed shortage period in the fall[1]. In this context, setting targets for grazing height can be an effective tool for the production of forage in quantity and quality, as this has been shown to be an integrative variable, relating to several processes that occur at sward canopy level [2,3]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
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
