ISSN:
1365-3180
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
The foliar surface of 4-leaf maize plants was found to be poorly wettable and retained 106 μl g−1 dry matter when sprayed with a U46D (2,4-D formulation) blank. The third leaf retained 141 μl g−1. A 7-day cold spell (17/9°C) increased retention per unit dry matter by 53% (135% on the third leaf). Cold stress lowered epicuticular wax quantity by 29% on the third leaf. Contact angles of formulated 2,4-D lay between 115 and 125° and were not significantly affected by cold stress. 2,4-D rapidly entered into maize third leaf (66% in 24 h) but migration from it was less than 1.5%. 2,4-D was readily degraded in maize (80% in 72 h). The most abundant metabolite was probably an ester conjugate; little of the hydroxy derivatives were found. Cold stress reduced 2,4-D degradation, and 72 h after treatment the amount of undegraded 2,4-D was 78% higher in cold-stressed maize plants. It was concluded that 2,4-D selectivity in maize results from low spray retention per unit dry matter and active degradation of penetrated herbicide. Cold stress affects both factors.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1365-3180.1991.tb01752.x
