Effects of Reduced Tillage and Multiple Cropping on Plant Diseases

Abstract

SUMNER, DOUPNIK & BOOSALIS Multiple cropping: The intensification of cropping in time and space such as growing two or more crops on the same fi eld in a year. Sequential cropping: Growing two or more crops in sequence on the same field per year where the succeeding crop is planted after the preceding crop is harvested (double cropping, triple cropping, and quadruple cropping). Intercropping: Growing two or more crops simultaneously on the same field. Monocropping: Growing one crop on a fi eld each year. Monoculture: The repetitive growing of the same crop in the same land. More detailed explanations of other terms used in multiple cropping are given in other papers (5, 7, 74, 75, 85). Tillage in agriculture is the changing of soil conditions for crop produc tion (2). Definitions used for tillage practices are as follows: Conventional tillage: Traditional tillage system, which typically begins with a primary deep tillage operation followed by some secondary tillage for seedbed preparation (7). Conservation tillage: Any tillage practice that reduces loss of soil or water compared to unridged [soil is not mounded into a specifi c confi guration (2)] or clean tillage (85). Minimum tillage: That minimum amount of tillage required to create the proper soil condition for seed germination and plant establishment (85). Notill age, zero tillage: A method of planting crops that involves no seedbed preparation other than opening the soil for the purpose of placing the seed at the intended depth. This usually involves opening a small slit or punching a hole into the soil. There is usually no cultivation during crop production. Chemical weed control is normally used (85). Chiseling: A tillage operation in which a narrow tool is used to break up hard soil. It may be performed at other than the normal plowing depth (2). Plowing: A primary tillage operation which is performed to shatter soil with partial or complete soil inversions (2). Subsoiling: Tillage of sll;bsurface soil, without inversion, below 406 mm, to break up dense layers that �estrict water movement and root penetration (2,85). Reduced tillage systems have been established in many areas of the world and will become increasingly important in other areas where soil moisture

Early Leafspot of Peanuts: Effect of Conservational Tillage Practices on Disease Development1

“…This reduces the possibility of returning infested peanut residues from the previous crop to the soil surface to initiate infection. The micro-environment associated with conservational tillage systems may also be less conducive to disease development than that of conventional tillage systems (13). Soil moisture is usually higher and temperatures are cooler in conservational tillage systems than in conventional tillage systems.…”

Controle de doenças de plantas pela rotação de culturas

“…de Bary. O plantio direto pode interferir drasticamente na oferta de substrato para os patógenos e consequentemente na sua dinâmica populacional (26).…”

Control of winter forage pea diseases by pea-oat intercropping under field conditions

“…Several authors have reported other advantages of intercropping as well: better usage of environmental resources, improved soil fertility and nitrogen increase, less pesticides used, improved forage quality, yield stability and uniformity and finally -an increase in overall production (Sumner et al, 1981;Mousavi & Eskandari;, Kadžiulienė et al, 2011.…”