Support capacity, production and composition of three grasses sward or not irrigated during the drought

Abstract

This study aimed to assess the carrying capacity, production and morphological composition
of 3 or not irrigated forage during drought. The experimental design was a 3x2 factorial
arrangement with three forages (Panicum maximum cv Tanzania, Cynodon spp cv Tifton 85
and Urochloa mosambicensis), irrigated or not. Data were subjected to analysis of variance
and means were compared by Tukey test at 5%. It was observed a significant interaction (P
<0.05) in DM production. In Tanzania the area without irrigation had higher DM yield than
Urocloa, both of which did not differ from Tifton 85. Irrigated area in DM yield of Tifton 85 was higher than the other, and the Tanzania was higher than Urocloa. On average DM yield
was higher in the irrigated area. It was observed a significant interaction (P<0.05) in the
production of green leaf blade (GLB). In the non-irrigated area of Tanzania GLB was higher
than the others, and the Tifton 85 and Urocloa did not differ. Irrigated area in Tanzania had
the largest GLB than others, and the Tifton 85 was greater than the Urucloa. The GLB
production was higher in the irrigated area. It was observed a significant interaction (P<0.05)
in relation lamina leaf: stem ratio (RLS). In two areas the largest RLS Tanzania had that too,
and Urocloa and Tifton 85 did not differ. The RLS Tanzania was the largest in the area
without irrigation, the RLS Urocloa Tifton 85 and did not differ between areas. We observed
a significant interaction (P<0.05) in support capacity (SC). In the non-irrigated SC Tifton 85
was higher than Urocloa, both of which did not differ from Tanzania. Irrigated area in the SC
Tifton 85 was higher than the others, and the Tanzania had the highest SC Urocloa. The SC
was higher in the irrigated area.