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- Author or Editor: Timothy J Ng x
Crop Genetics Cooperatives tend to be grassroots organizations comprised of individuals with interests in the genetics and/or breeding of a specific crop plant species, genus, or family. Activities of Genetic Cooperative often involve publishing informal research reports, compiling linkage maps, and serving as a repository for monogenic variants in the crop(s) of interest. However, information circulation is often limited to the Cooperative's membership since these organizations are rarely affiliated officially with a specific institution. Fortunately, the rapidly increasing capabilities of the World Wide Web (WWW) now allow Genetics Cooperatives to expand their outreach and provide information to anyone with Internet access. The features of WWW also allow frequent updating of information as necessary for items such as genetic maps and gene collections. The Cucurbit Genetics Cooperative (CGC) is typical of many of these organizations, and CGC is in the process of archiving back issues of the CGC Annual Report on WWW while providing current gene listings and mutant collection information to the scientific community. In addition, software such as databases and programs for analyzing genetic studies are available for downloading, and links are provided to genetic resources at other locations around the world. The process and progress of setting up the CGC website will be described, as well as plans for the future.
The National Information Infrastructure (NII) initiative, more commonly known as the “information superhighway,” is intended to provide high-speed electronic access to a variety of voice, data, video, and other information services by the year 2000. Initial access to the superhighway will be prioritized for classrooms, libraries, hospitals and clinics. Eventually NII will provide for widespread and open availability of telecommunication and information services to everyone.
Access to NII will be provided via electronic networks, telephone companies and cable operators. Many of the features proposed by NII are currently available in a developmental stage to horticulturists. The accessibility and future evolution of these services--which include those available via Internet (e.g., electronic messaging, data and information services, document delivery) and via telephone and cable companies (e.g. video/audio “on demand,” real-time polydirectional compressed video) --will be discussed.
The World Wide Web (WWW) provides users with a graphical computer interface to access digital information from Internet locations around the world. This information may be in the form of text, images, motion pictures, or sound. Web “pages” may also provide near-instantaneous links to other pages with related interests and information, and have the capability of allowing users to fill out forms on-line requesting additional information or services. WWW access is becoming increasingly available to individuals either through direct network links or by a modem connection through an Internet provider, the latter method generally requiring either SLIP or PPP service to establish a link. The background of WWW, its potential, and its future development will be discussed.
‘MaryGold’ is a white-fleshed casaba muskmelon (Cucumis melo L. Inodorus group) adapted to the climatic and cultural conditions prevalent in the Mid-Atlantic region of the United States. It is andromonoecious and produces oval, bright yellow, medium-sized fruits with a slightly wrinkled rind free of net. It is resistant to race 2 of fusarium wilt [Fusarium oxysporum f. melonis (Leach and Currence) Snyder and Hansen] and race 1 and race 2 of powdery mildew [Sphaerotheca fuliginea (Schlect ex Fr.) Poll], It stores well and is suitable for shipping as well as for local markets.
Muskmelon (Cucumis melo L.) plants primarily are pollinated by honey bees (5) and naturally pollinated fruits contain highly varying percentages of self-pollinated seed (3, 8). Muskmelon breeders often rely on controlled hand pollinations for making out-crosses and self-pollinations in the field; natural pollinators must be excluded from perfect or pistillate flowers until fruit set has occurred. If fruits are set from natural pollination, they often are removed since the presence of fruits on a plant may suppress subsequent fruit set (4).
Twenty-five melon (Cucumis melo L.) cultigens were screened for resistance to fusarium wilt in a field infested with race 1 and race 2 of Fusarium oxysporum f.sp. melonis in 1993 and 1994. Plants were grown on clear plastic mulch using commercial production recommendations. The soil was fumigated with methyl isothiocyanate at a broadcast rate of 340 liters·ha–1 in 1993, and with dichloropropene at a broadcast rate of 136 liters·ha–1 in 1994. Resistance was determined by the percentage of plants surviving 8 weeks after transplanting. In general, highly resistant cultigens (>90% survival) and highly susceptible cultigens (<20% survival) performed consistently in the two experiments. However, differences in performance between the two years were noted for cultigens with intermediate resistance, and their performance may have contributed to the significant cultigen × year interaction in this study.
Two netted and three nonnetted (casaba) muskmelon (Cucumis melo L.) cultigens and their hybrids were examined after harvest for ethylene production and for concentration of ethylene in the cavity. Whole fruit ethylene production was related to cavity concentrations. Netted muskmelon fruit produced appreciable amounts of ethylene at or near harvest while nonnetted fruit did not produce ethylene until as late as 20 days postharvest. Hybrids were generally intermediate to the parents in rate and time of production of ethylene, thus demonstrating that rates of ethylene production and cavity concentrations of ethylene in muskmelon fruit appear under genetic control.
Five parental cultivars of muskmelon (Cucumis melo L.) and 16 F1 hybrids, including six reciprocals, were evaluated in a diallel design for reaction to inoculations with Myrothecium roridum and its phytotoxic metabolite roridin E using a detached leaf screening test. Analyses of variance revealed genetic variability for tolerance to the fungus and to the toxin; the correlation coefficient between inoculations with the pathogen and the toxin was 0.94. Disease and toxin tolerance were associated with highly significant general combining ability (GCA) effects, but specific combining ability were significant only for inoculations involving the pathogen. The GCA component accounted for 95.8% of the genotypic variation for pathogen tolerance and 99.3% for toxin tolerance. Reciprocal effects were not present in either set of inoculations.
Seeds of 2 cultivars of muskmelon (Cucumis melo L.) were subjected to accelerated aging at 45°C and 100% relative humidity (RH) for periods up to 288 hours. In general, longer periods of aging resulted in greater declines in seed quality as measured by laboratory, greenhouse, and field emergence and germination. Seeds of ‘Iroquois’ were more sensitive to aging than ‘Hale’s Best #36’. Significant declines in germination occurred prior to any significant increases in electrolytic leakage from decorticated seeds indicating that electrolytic leakage is not a suitable test for seed quality with muskmelon.