TITLE:
Infestation of Diatraea saccharalis (Fabr.) during Five Consecutive Cycles of Sugarcane Crop Succeeding Leguminous Crops
AUTHORS:
Edmilson José Ambrosano, André Luiz Lourenção, Elaine Bahia Wutke, Fabricio Rossi, Fábio Luis Ferreira Dias, Silvio Tavares, Gláucia Maria Bovi Ambrosano
KEYWORDS:
Arachis hypogaea L., Crotalaria juncea L., Mucuna aterrima (Piper & Tracy) Holland, Saccharum spp., Sugarcane Borer
JOURNAL NAME:
Agricultural Sciences,
Vol.6 No.1,
January
8,
2015
ABSTRACT: The area cultivated
with sugarcane in Brazil is expanding, and increasingly using legumes cover
crop in new deployed areas and in those which were reformed. Long-term trials
were carried out in Piracicaba, Sao Paulo, Brazil, to evaluate the effect of
leguminous green manure on the natural infestation of Diatraea saccharalis (Fabr.) during five cropping cycles of
sugarcane “IAC 87-3396”. This study was carried out from October 1999 to
October 2005 in Piracicaba, Sao Paulo, Brazil, at coordinates 22°42''S and 47°38''W,
560 m above sea level, in soil classified as Typic Paleudult. Green manure
crops were assigned to five treatments: peanuts (Arachis hypogaea L.) (cultivar “IAC-Tatu” and “IAC-Caiapó”), sunn
hemp (Crotalaria juncea L.) (cultivar
“IAC 1”) and velvet-bean [Mucuna aterrima (Piper & Tracy) Holland] (cultivar “common”). A treatment without any green
manure or weed was used as the control. The previous sugarcane
crop was destroyed and the soil was prepared in a conventional way (using plow
and harrow) before the leguminous crops were sowed. Thirty days after the sowing,
weeds were removed and, 120 days later, the crops were cut and its biomass was
deposited on the soil surface without incorporation. Experimental plots comprised
five rows of sugarcane, each one measuring 10 m long and spaced 1.40 m apart. The
sugarcane was harvested 18 months after biomass deposit, on October 25th, 2001
and its stalks were collected at intervals of approximately 12 months in:
07/09/2002, 08/01/2003, 11/07/2004 and 10/06/2005. At harvest, the masses were
determined from a sample of sugarcane, cut from three rows (2 m long) in the
center of the plot. The losses caused by the sugarcane borer were estimated by
the intensity of the infestation by randomly observing and collecting sugarcane
stems from each plot. A great reduction in the number of stalks and in the
yield was noted proportionally to the intensity of the infestation of the borer
in the sugarcane crop grown after the velvet-bean. The sugarcane-velvet-bean
rotation should be regarded considering the intensity of sugarcane borer
infestation. No influence of the other green manure crops was observed on the
intensity of the infestations. However, the harvest seasons of the sugarcane seemed
to influence the borer infestation.