Comparing low rate copper formulations against Phythophthora infestans in potatoes

Between Dutch organic growers the late blight problems lead to discussions in which a temporary registration of copper products is also suggested. Some growers do not want any pesticides at all, while others see that biological potatoes from abroad are sold in the super markets in years when Dutch organic potatoes are scarce. Those potatoes come from countries, where copper products are allowed. They speak about competition falsification. In the research program to stimulate organic production the choice is made to also investigate the efficacy of copper and other products that are allowed in surrounding countries in organic farming. In the experiment of 2008 6 different copper containing products are tested

Low rate copper products to control Phytophthora infestans in potatoes in 2009

Between Dutch organic growers the late blight problems lead to discussions in which a temporary registration of copper products is also suggested. Some growers do not want any pesticides at all, while others see that biological potatoes from abroad are sold in the super markets in years when Dutch organic potatoes are scarce. Those potatoes come from countries, where copper products are allowed. They speak about competition falsification. In the research program to stimulate organic production the choice is made to also investigate the efficacy of copper and other products that are allowed in surrounding countries in organic farming. In the experiment of 2008 different copper containing products are tested. In 2009 this was repeated with the same products, but also other doses and combination

Control of Phytophthora infestans with low copper amounts in potatoes in 2010

Between Dutch organic growers the late blight problems led to discussions in which a temporary registration of copper products is also suggested. In the research program to stimulate organic production the choice was made also to investigate the efficacy of copper and other products that are allowed in neighbouring countries in organic farming. In the experiment of 2008 different copper containing products were tested. In 2009 this was repeated with the same products, but also other doses and combinations. In 2010 the most important objective of the experiment was to investigate the possibilities of a maximum of 300 gram copper per hectare, divided in different parts, in combination with a decision support system. 300 gram copper was based on the amount different crops need in a six year organic rotation. Except a standard copper product also a copper product used in organic farming in the Netherlands as a leaf fertilizer was used and some products financed by the industry

PlantyOrganic: Design and results 2012

Increasingly strict legislation about fertilizer inputs and developing organic regulations are a strong stimulation to optimize the internal nutrient dynamics of organic arable farms. In the project “PlantyOrganic” , initialized by Biowad and realized at SPNA location Kollumerwaard, a challenging arable system is developed and tested: 100% internal nitrogen supply without input of nutrients from outside. In this report the design of the rotation and fertilizer scheme is presented and discussed, and the starting conditions in spring 2012 are documented. The NDICEA nitrogen model is used to explore the nitrogen dynamics. It is concluded that a 100% farm-own nitrogen supply can be achieved with good production levels. The 2012 results gave no reason to reconsider the rotation and fertilizer design, but since this was the first year of this experiment none of the crops had the precrop as foreseen in the design and the fertilizer used was only partly cut-and-carry fertilizer

The 2060 Chiron: CCD photometry

R-band CCD photometry of 2060 was carried out on nine nights in Nov. and Dec. 1986. The rotation period is 5.9181 + or - 0.0003 hr and the peak to peak lightcurve amplitude is 0.088 + or - 0.0003 mag. Photometric parameters are H sub R = 6.24 + or - 0.02 mag and G sub R = + or - 0.15, though formal errors may not be realistic. The lightcurve has two pairs of extrema, but its asymmetry, as evidenced by the presence of significant odd Fourier harmonics, suggests macroscopic surface irregularities and/or the presence of some large scale albedo variegation. The observational rms residual is + or - 0.015 mag. On time scales from minutes to days there is no evidence for nonperiodic (cometary) brightness changes at the level of a few millimagnitudes

A Spectroscopic Comparison of HED Meteorites and V-type Asteroids in the Inner Main Belt

V-type asteroids in the inner Main Belt (a < 2.5 AU) and the HED meteorites are thought to be genetically related to one another as collisional fragments from the surface of the large basaltic asteroid 4 Vesta. We investigate this relationship by comparing the near-infrared (0.7-2.5 micron) spectra of 39 V-type asteroids to laboratory spectra of HED meteorites. The central wavelengths and areas spanned by the 1 and 2 micron pyroxene-olivine absorption bands that are characteristic of planetary basalts are measured for both the asteroidal and meteoritic data. The band centers are shown to be well correlated, however the ratio of areas spanned by the 1 and 2 micron absorption bands are much larger for the asteroids than for the meteorites. We argue that this offset in band area ratio is consistent with our currently limited understanding of the effects of space weathering, however we can not rule out the possibility that this offset is due to compositional differences. Several other possible causes of this offset are discussed. Amongst these inner Main Belt asteroids we do not find evidence for non-Vestoid mineralogies. Instead, these asteroids seem to represent a continuum of compositions, consistent with an origin from a single differentiated parent body. In addition, our analysis shows that V-type asteroids with low inclinations (i < 6 degrees) tend to have band centers slightly shifted towards long wavelengths. This may imply that more than one collision on Vesta's surface was responsible for producing the observed population of inner belt V-type asteroids. Finally, we offer several predictions that can be tested when the Dawn spacecraft enters into orbit around Vesta in the summer of 2011.Comment: 27 pages, 11 figures, 6 tables, Accepted to Icaru

The Short Rotation Period of Nereid

We determine the period, p = 11.52 \pm 0.14 h, and a light curve peak-to-peak amplitude, a = 0.029 \pm 0.003 magnitudes, of the Neptunian irregular satellite Nereid. If the light curve variation is due to albedo variations across the surface, rather than solely to the shape of Nereid variations, the rotation period would be a factor of two shorter. In either case, such a rotation period and light curve amplitude, together with Nereid's orbital period, p=360.14 days, imply that Nereid is almost certainly in a regular rotation state, rather than the chaotic rotation state suggested by Schaefer and Schaefer (1988,2000) and Dobrovolskis (1995). Assuming that Nereid is perfectly spherical, the albedo variation is 3% across the observed surface. Assuming a uniform geometric albedo, the observed cross sectional area varies by 3%. We caution that the lightcurve found in this paper only sets limits on the combination of albedo and physical irregularity and that we cannot determine the orientation of Nereid's spin axis from our data.Comment: Accepted by ApJ Letters, 11 pages (incl. 1 figure