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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Studies on the biology and mortality of the carrot fly, Psila rosae F. (Diptera:Psilidae)

Vincent, Julia January 1999 (has links)
Field and laboratory experiments were done to quantify the effects of high temperature and low soil moisture on the mortality of the immature stages of the carrot fly (Psila rosae F.). Field experiments related fly numbers to egg density and determined the period within each 8-10 week fly generation that resulted in most crop damage at harvest. Population monitoring: From 1995-1998, all stages of the carrot fly were monitored. No third fly generation was observed and no first-instar larvae were found after the end of September. Periods of high mortality were identified. [~gg mortality: Mortality was related linearly to the mean maximum soil temperature at 1 cm depth during egg development (m = 8.4t -167.3; m = % mortality, t = temperature). Under controlled conditions, eggs in dry soil died sooner at higher temperatures (>25°C) than eggs in moist soil. Fully developed eggs were more susceptible to adverse abiotic conditions than newly-laid eggs. Larval mortality: Up to 90% of first-instar larvae were killed by low soil moisture in the field. This mortality was related to the length of time larvae were exposed to dry soil conditions (m = 2.6 + 17.6d; m = % mortality, d = no. of days in dry soil). Relationship between numbers offlies and egg density: A linear relationship (e = 0.32 + 0.89[; e = log no. eggs, f = log no. flies) was identified between the numbers of carrot flies caught on sticky traps and the numbers of fly eggs recovered from carrot crops. Critical egg-laying period: Within a generation, the critical egg-laying period when most damage was caused was between 10-20 days. This coincided with the peak in fly numbers. Rearing method: A robust rearing method was developed for producing a regular supply of adults. Approximately 50% of eggs inoculated onto growing carrots gave rise to pupae.
72

Further studies of the bacterial necrosis of the giant cactus

Boyle, Alice McLaughlin, 1904- January 1948 (has links)
No description available.
73

An evaluation of cotton pest management practices in Pinal County, Arizona, 1974

Olmstead, Steven Dana, 1949- January 1976 (has links)
No description available.
74

Insect/host-plant interactions of the western flower thrips and alfalfa

Martin, Bradford Eugene January 1978 (has links)
No description available.
75

SOME RHIZOCTONIA SOLANI (KUEHN)-ALFALFA (MEDICAGO SATIVA L.) RELATIONSHIPS

El-Khash, Mohammed Najib, 1927- January 1969 (has links)
No description available.
76

EFFECTS OF LYGUS HESPERUS (KNIGHT) ON GROWTH, YIELD, AND QUALITY OF COTTON

Jubb, Gerald Lombard, 1943- January 1970 (has links)
No description available.
77

MECHANISMS OF RESISTANCE IN ALFALFA, MEDICAGO SATIVA (L.) TO THE ALFALFA SEED CHALCID, BRUCHOPHAGUS RODDI (GUSSAKOVSKII)

Tingey, Ward Max, 1944- January 1972 (has links)
No description available.
78

INHERITANCE AND ETIOLOGY OF AN UNDESCRIBED ROOT DISEASE IN SORGHUM BICOLOR (L.) MOENCH

Burns, Marvin, 1947- January 1974 (has links)
No description available.
79

Control of Garden Pests

Tate, Harvey F., Roney, J. N. 05 1900 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
80

Control Garden Insects

Roney, J. N. 05 1900 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.

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