Search Results
Abstract
Pepper (Capsicum frutescens L.) and summer squash (Cucurbita pepo var. melopepo (L.) Alef.) were grown in immediate succession in undisturbed beds using trickle irrigation with various treatments. Highest combined yield in metric tons/ha for both crops was obtained with film mulch + soil fumigation (117.6) followed by film mulch (112.3), soil fumigation (93.4) and control (69.0), respectively. Yield from the second crop was negatively correlated (r=−.87) with the degree of plant infection with root-knot nematode (Meloidogyne incognita (Kofoid & White) Chitwood). Intensive production in this manner allows fixed costs to be defrayed over two crops thus increasing the magnitude of return per dollar invested. Multiple cropping of pepper and squash with trickle irrigation has an excellent potential in south Georgia provided nematodes and other soil-borne pathogens can be adequately controlled.
Abstract
‘LaJewel’ is a late season peach for fresh and pick-your-own marketing, maturing about 15 days after ‘Elberta’. Fruits are freestone with yellow flesh. Resistance to bacterial spot [Xanthomonas campestris pruni (Smith) Young et al.] is high.
Abstract
Marketable tomato yields were influenced more by applied N than by irrigation. Irrigation increased total marketable tomato yields only at the intermediate level. Average yields for the 3-year period by soil water regimes were about 58,300, 70,000, and 68,900 kg/ha for no, intermediate, and high irrigation, respectively. Applied N increased yields, but the increase was limited mainly to the lowest application rate (65 kg/ha) in 1971 and 1972, and to the 2 lowest rates (65 and 130 kg/ha) in 1973. Average yields for the test period by N application rates were about 53,500, 67,100, 69,900, 70,600 and 67,600 kg/ha for 0, 65, 130, 195, and 260 kg/ha rates, respectively. These data indicate that the best combination of N rate and soil water regime was 65 to 130 kg/ha of applied N and supplemental irrigation as needed to maintain 30% or more available water in 0 to 60 cm soil depth.
Abstract
Magnesium sulfate applied as a soil amendment (34 kg Mg/ha annually for 3 years or a single application of 224 kg Mg/ha) increased leaf Mg 5 years after initial application. Dolomite increased soil pH and soil test Mg but not leaf Mg. Sulfate of potash magnesia and MgO increased soil test Mg and slightly, though insignificantly, increased leaf Mg. Single foliar sprays of MgSO4 and Mg(NO3)2 did not affect leaf Mg.
Abstract
Different rates of N, P, and K on southernpea Vigna unguiculata (L.) Walp. grown for one-time harvest during 4 years in field experiments on Alaga sand (Typic Quartzipsamments) soil showed that N had the greatest effect on yield of mature green southernpeas. Pea yields increased to a maximum of 67 kg/ha of N. Soil test P ranged from high to extremely high in the untreated soil; therefore, fertilizer P did not affect yield. Yields were increased by K only in the location-year in which soil-test K was low. At 35 days there was an increase in leaf N concentration as the rates of N were increased from 34 to 101 kg/ha; at 49 days the N concentration was lower and was not affected by N rates. Increasing fertilizer rates of K increased leaf concentration of K at both 35 and 49 days. Fertilizer P did not affect N, P, or K concentration.
Abstract
Effects of different nematicides on yields of sweetpotatoes and on root-knot nematode (Meloidogyne incognita) damage at two different locations were studied over a period of 3 years. Average yields of marketable size roots were significantly increased on Hartsells fine sandy loam from use of Penphene, D-D, Dowfume W-85, Telone, and Nellite; the increased yield from Furadan was nearly significant. All nematicides reduced the root-knot infection counts on steam-peeled roots and root-knot larvae per pint of soil at harvest. Furadan gave the best nematode control. Average' yields were increased on Alaga sand from use of Penphen, D-D, D-D + SD14647, Vorlex, Furadan, Temik, and Mocap. Average root-knot infection counts and root-knot larvae per pint of soil at harvest were significantly reduced by all nematicides used; the greatest reductions followed applications of Temik, Mocap, Furadan, and D-D + SD14647.
Abstract
Millet, milo, soybean, crotalaria and Norman pigeon pea were used in conjunction with clean fallow and a nematicide (fensulfothion) for managing root-knot nematode populations in tomato (Lycopersicon esculentum Mill.) transplant production. Clean fallow was most effective in suppressing numbers of nematodes. After 2 years, numbers of nematodes increased to damaging levels and fallow was no longer effective for complete control even when used in conjunction with fensulfothion. After 4 years none of the crops used as summer cover crops alone or in conjunction with fensulfothion reduced numbers of root-knot nematodes in harvested tomato transplants sufficiently to meet Georgia regulations.
European red mite (Panonychus ulmi) populations were monitored in a tart cherry (Prunus cerasus `Montmorency') orchard and the effects on photosynthesis determined. Mites levels were controlled in some trees by miticide applications to establish different cumulative mite*days in the trees. Photosynthetic inhibition caused by insect injury was also simulated by spraying other trees with 78 ppm Terbacil at one of four different times during the season, The mite*days accumulated in 1993 ranged from 937 to 2205, however, there were no differences in single leaf or whole tree CO2 assimilation, chlorophyll a fluorescence, or chlorophyll levels among the different levels of mite damage. Likewise, there were no differences in these same parameters among the Terbacil-treated trees except that photosynthesis was reduced on treated trees for 10-14 days, after which photosynthesis recovered to the level of the controls. There were no differences in yield or fruit quality among any treatments, and cold hardiness and return fruiting characteristics will be measured.