Predation of Ostrinia nubilalis (Lepidoptera: Crambidae) Eggs in Sweet Corn by Generalist Predators and the Impact of Alternative Foods

Generalist predators are common in most agricultural cropping systems. However, pest control from these predators is often overlooked as a component of integrated pest management (IPM) because the extent of predation is generally unknown and difficult to assess. In western New York sweet corn (Zea mays L.), the primary predators are Orius insidiosus (Say), Coleomegilla maculata (DeGeer), and Harmonia axyridis (Pallas). European corn borer [Ostrinia nubilalis (Hübner)] is the primary insect pest. The objectives of this study were to compare O. nubilalis egg predation rates for these three species and to understand how egg predation by these predators is affected by the availability of alternative food. Laboratory data indicate that all three predators feed on O. nubilalis eggs. C. maculata consumed more eggs than H. axyridis or O. insidiosus. Immatures of C. maculata and O. insidiosus readily completed development on a diet of O. nubilalis eggs, but H. axyridis larvae could not complete development on this diet. The presence of corn leaf aphids [Rhopalosiphum maidis (Fitch)] and corn pollen reduced egg predation per insect for some stage of all species. The reduction in O. nubilalis egg predation associated with the presence of aphids was confirmed in field cage studies and was similar among the coccinellid populations tested. Field studies comparing aphids, predator populations, and O. nubilalis egg predation show that reduced egg predation per insect more than offsets the higher populations encountered when aphids and pollen are numerous, resulting in less biological control of O. nubilalis when alternative foods are availabl

Factors Altering the Temporal and Within-Plant Distribution of Coccinellids in Corn and Their Impact on Potential Intra-guild Predation

In New York, the primary coccinellid in corn and sweet corn (Zea mays, L.) has historically been Coleomegilla maculata (DeGeer). However, Harmonia axyridis (Pallas) has also been observed the last few years. The objectives of this study were to document the level of establishment of both species in corn and sweet corn and to understand their interactions. The temporal and within-plant distributions of all coccinellids were recorded for 3 yr. The results indicated that H. axyridis and C. maculata were the only abundant coccinellids in corn and sweet corn, with adults and larvae of both species having distinct temporal and within-plant distributions. C. maculata adults were found earlier in the season and lower on the plant than H. axyridis adults. Larvae of both species were often found at the same time and were lower on the plant than their respective adults. Temporal distributions of both species were correlated to crop maturity, aphid density, planting date, and corn type, but not to nearby vegetation. The within-plant locations were correlated to crop maturity, aphid density, planting date, nearby vegetation, and the presence of conspecific coccinellids. While the distribution of each population was unique, some C. maculata and H. axyridis shared time and space, providing the potential for intra-guild predation. An encounter between H. axyridis and C. maculata was most likely to occur when the corn had high aphid populations during pollen shed. These extraguild food sources minimize intra-guild predation, allowing these two species to co-exist in New York corn and sweet corn field

1962

Turf on the Launching Pad (page 1) Turf management Club News (3) Education, Experience and Attitude (4) A Blade of Grass (5) Picture - Professor Lawrence S. Dickinson (6) Picture - Thomas Mascaro - Banquet Speaker (7) Planting Trees on the Golf Course (8) Two-Way Radios (8) Greens Mowing Procedure (9) Watering and Topdressing as Related to Poa annua Infestations (10) Picture - Stockbridge Majors in Turf Management (12) Picture - Graduates of Winter School for Turf Managers - 1962 (13) Review of Season\u27s Pests by Joseph Troll (A-1) Today\u27s Trends in Golf Course Development by Col. Harry C. Eckoff (A-3) Breeding and Selection of Fine Turf Grasses by Dr. B. R. Anderson Penncross Bentgrass by J. Dutch(A-13) Poa annua by Alexander Radko (A-16) Velvet Bent by Jesse DeFrance (A-19) Vegetative Creeping Bentgrasses by Fred Grau (A-21) Modification of SOils for Green Construction & Top Dressing by Prof. H. B. Musser (A-27) Soil COmpaction by Donald Waddington (A-32) Irrigation Practices and the Need of Basic Research by Prof. Edward PIra (A-36) Water Sources by Z. Mills (A-39) Athletic Field Maintenance by Thomas Mascaro (A-41) Planning the Landscape Around the House by Prof. Harold Mosher (A-43

IMPACT OF CAPITAL GAINS TAXATION ON FARM ORGANIZATION: IMPLICATIONS FOR MEAT ANIMALS PRODUCTION ON DIVERSIFIED FARMS

Agricultural economists have devoted considerable research efforts to measuring aggregate capital gains accruing to the U.S. agricultural sector and their effect on the welfare of farm families (Bhatia, Evans and. Simunek, Hoover, Melichar and Sayre). A specific research issue concerning capital gains is preferential treatment under federal income taxation statutes. Carmen (1968, 1969) outlined the general tax shelters provided by capital gains taxation and explored the example of beef breeding herds in some detail. Vandeputte and Baker demonstrated that preferential capital gains taxation encourages extensive rather than intensive farm firm growth

Impact of a glossy collard trap crop on diamondback moth adult movement, oviposition, and larval survival. Entomologia experimentalis et applicata, 117 : 71–81

Abstract One component of developing a systematic approach for deployment of trap crops is to understand how the trap crop modifies pest behavior. Glossy-leafed collards, Brassica oleracea L. var. acephala (Brassicaceae), were evaluated as a potential trap crop for diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), because they are attractive to P. xylostella adults and are a poor host for P. xylostella larvae compared to cabbage, Brassica oleracea L. var. capitata . We used large field plots to measure the changes in adult, egg, and larval P. xylostella densities in cabbage when the trap crop was planted in the field. Furthermore, we planted the trap crop in dispersed and concentrated spatial arrangements to determine the impact of trap crop arrangement on the behavior of P. xylostella . In 2002, results showed that the presence of collards within a cabbage field reduced larval density on cabbage. In 2003, neither trap crop arrangement had a significant impact on P. xylostella larval density on cabbage. Adult moths aggregated in proximity to collards in 2002, but not in 2003. Egg and larval data in both years in all treatments showed that total oviposition was highest near a central release point, indicating that females lay many eggs before dispersing very far when suitable host plants are available. The mean direction of P. xylostella movement and oviposition from a central release point was not consistent or correlated to wind direction. Plant size of the trap crop in relation to the main crop and environmental factors may have been responsible for the inconsistent effectiveness of the trap crop

Impact of a glossy collard trap crop on diamondback moth adult movement, oviposition, and larval survival. Entomologia experimentalis et applicata, 117 : 71–81

Abstract One component of developing a systematic approach for deployment of trap crops is to understand how the trap crop modifies pest behavior. Glossy-leafed collards, Brassica oleracea L. var. acephala (Brassicaceae), were evaluated as a potential trap crop for diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), because they are attractive to P. xylostella adults and are a poor host for P. xylostella larvae compared to cabbage, Brassica oleracea L. var. capitata . We used large field plots to measure the changes in adult, egg, and larval P. xylostella densities in cabbage when the trap crop was planted in the field. Furthermore, we planted the trap crop in dispersed and concentrated spatial arrangements to determine the impact of trap crop arrangement on the behavior of P. xylostella . In 2002, results showed that the presence of collards within a cabbage field reduced larval density on cabbage. In 2003, neither trap crop arrangement had a significant impact on P. xylostella larval density on cabbage. Adult moths aggregated in proximity to collards in 2002, but not in 2003. Egg and larval data in both years in all treatments showed that total oviposition was highest near a central release point, indicating that females lay many eggs before dispersing very far when suitable host plants are available. The mean direction of P. xylostella movement and oviposition from a central release point was not consistent or correlated to wind direction. Plant size of the trap crop in relation to the main crop and environmental factors may have been responsible for the inconsistent effectiveness of the trap crop

A MODEL TO CALCULATE THE COST OF CAPITAL FOR FARM FIRMS

This paper presents a method for calculation of the cost of capital for farm firms from income tax records and supplementary information. While data were only available for one year, the model developed in this paper could be applied in a farm management context for time series information. Specific objectives of this paper include: (1) theoretical identification of the type of data needed to calculate the cost of capital for a farm firm, (2) illustration of the estimation procedure for case farms, and (3) presentation of some aggregate estimates of the cost of capital