Oilseed Radish Effects on Soil Structure and Soil Water Relations

Abstract

Oilseed radish (Raphanus sativus spp. oleifera) reduces sugarbeet cyst nematode (Heterodera schachtii) populations. Fall-incorporated radish biomass may also increase the yield and quality of subsequently grown sugarbeet (Beta vulgaris L.) by improving soil physical and hydraulic properties. This field study determined radish effects on nearsurface soil aggregate stability, water-stable aggregate size distribution, bulk density, and field-saturated water content, as well as infiltration and hydraulic conductivity measured at water supply potentials of -40, -20, and +0 mm H 2 O. In 2003 and 2004 in Twin Falls, ID, radish were grown in a Portneuf silt loam (Durinodic Xeric Haplocalcid) for about 10 weeks in the fall, then incorporated later that fall by disking, followed by moldboard plowing. In early May of the following year, sugarbeet were planted, irrigated, then harvested for yield and quality. In the spring and fall of each sugarbeet growing season, soil samples were collected from two depths, 0 to 5 and 5 to 50 mm, on which we measured aggregate stability and size distribution by wet sieving. Soil cores were collected from 0 to 34 mm to measure bulk density. Also in spring and fall, we used ponded and tension infiltrometers placed in the row to measure steadystate, unconfined infiltration rates and, from those rates, to Additional key words: Raphanus sativus, cover crop, Beta vulgaris, aggregate stability, infiltration rate, hydraulic conductivity W ater use efficiency is increased by improving soil water relations, such as infiltration or water retention, for crops grown in rotation. Adding oilseed radish (Raphanus sativus spp. oleifera) as a temperate-region, non-legume green manure into crop rotations with barley (Hordeum vulgare L.), wheat (Triticum aestivum L.), potato (Solanum tuberosum L.), and/or sugarbeet (Beta vulgaris L.) may enhance soil water relations.Green manures are crops that, while still green or soon after maturity, are incorporated into soil to improve the soil's physical, chemical, or biological properties and thereby increase the succeeding crop's yield, quality, or both (Cherr et al., 2006). Additions of organic matter, including that from an incorporated green manure, are commonly thought to increase soil organic carbon, aggregate stability, infiltration, and hydraulic conductivity (Martens and Frankenberger, 1992). Amendments can also reduce bulk density, alter soil pore size distributions, reduce a soil's susceptibility to erosion, and slow the formation of surface seals and crusts, thereby maintaining infiltration rates and thus delaying runoff (Bresson et al., 2001;Edmeades, 2003;Haynes & Naidu, 1998). Organic amendment effects on a soil's water-holding capacity (WHC) may or may not occur (Głąb and Kulig, 2008;MacRae and Mehuys, 1985). Adding organic matter may increase both the field capacity and permanent wilting point, resulting in little or no net change (Haynes & Naidu, 1998). Alternatively, such additions may decrease WHC, due to decreases in bulk density and chang...

Effect of Fodder Radish (Raphanus sativus L.) Green Manure on Potato Wilt, Growth and Yield Parameters

“…This increase in potato tuber yield using Brassicaceous species green manures was reported in several previous studies [30,38,54]. In this regard, Lehrsch and Gallian [64] find that planting radish as a green manure in the fall, prior to planting potato the following spring, leads to yield improvement in the grown potato as well as in the subsequent sugar beet crops. It has been proved that amongst six varieties of green manure crops, maximum beet yield was obtained from FR cv.…”

“…Boss and Defender, at a rate of 25 t/ha, had significantly enhanced all potato growth and yield parameters as compared to animal manure. In fact, potato average stem number per plant and aerial part fresh weight were respectively increased by 22 [64,70,71]. In this regard, Subbarao and Hubbard [72] find that the incorporation of broccoli residue results in consistently taller cauliflower plants with greater root and shoot biomass.…”

“…Larkin and Griffin [37] report that Brassicaceae crops, including radish, canola, rapeseed, turnip, yellow mustard, and Indian mustard are able to reduce inoculum levels of R. solani by 20-56% in greenhouse tests and to decrease subsequent potato seedling disease by 40-83%. Furthermore, oilseed radish incorporated earlier as a green manure has been observed to reduce Rhizoctonia Root and Crown Rot in sugarbeet and to decrease population of V. dahliae to a greater degree [64,65]. In addition, fodder and oilseed radishes have also shown efficacy in suppressing many soil-borne bio-agressors such as nematodes and bacteria.…”

“…In this sense, Lehrsch and Gallian [64] relate the increase in the yield and quality of sugar beet, after fall-incorporated radish biomass, to soil physical and hydraulic properties improvement. In this regard, Schomberg et al [76] report that oilseed radish grows rapidly in the fall and spring and can scavenge significant quantities of N. Furthermore, as oilseed radish produced a significant amount of biomass in the fall and early spring, it has been suggested that it could be useful in rotations where earlier planting dates are desired and for preventing leaching of residual N [76].…”

Range formula based on angle of dispersion and nozzle configuration from an impact sprinkler

“…The sizes of the droplets affect their velocity and the range of sprinkler. Larger droplets possess greater velocities that tends to produce large sprinkler range, while the range from smaller droplet is smaller because of low velocity [8][9][10][11] .…”