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Maturity at harvest determines seed viability and vigor. However, separating seeds from different stages of development can be difficult using existing seed sorting technologies. New technology non-destructively sorts seeds based on their chlorophyll fluorescence (CF), so seeds with the same dry weight but with different physiological maturates can be separated. We determined whether chlorophyll content of muskmelon (Cucumis melo L. cv. Top Mark) seeds changes during development and whether those changes were related to viability and vigor. Seed viability and vigor were determined using an Association of Official Seed Analysts wet paper towel germination test. `Top Mark' seeds from nine stages of development were run through the SeedMaster Analyzer (Satake USA Inc., Houston, Texas), which calculated the chlorophyll content of each seed. The CF signal was fed into a computer to obtain a frequency histogram. Forty, 45, and 55 days after anthesis (DAA) seeds had germination percentages of 96%, 98%, and 100%, respectively, the highest in the study. Fifty-five DAA had greater seed vigor and viability and contained the lowest CF values; 207 on the 1000-value scale. The less-mature seeds contained higher chlorophyll content and had the lowest seed vigor and viability. Seed vigor and chlorophyll content were negatively correlated in this study. All seeds with high CF values had low vigor, but not all seeds with low CF values have high vigor. Seed aging during storage can reduce viability and vigor independent of chlorophyll content. Based on chlorophyll content, the SeedMaster Analyzer can non-destructively remove immature, low-vigor seeds that have the same physical characteristics and weight as more mature seeds. Chlorophyll fluorescence technology may allow the seed industry to further improve seed quality and maximize vigor.

Ginger(Zingiber officinalis) is a spice crop with a variety of medicinal uses. Potentially, it may be suitable for ethnic production following necessary studies to determine optimum cultural conditions. The propagation of ginger from rhizomes was investigated using three growth media, three media moisture levels, and two types of propagules. The media were poultry compost amended with peat and perlite in a volume ratio of 2:1:1, municipal yard waste compost, and the commercial mix Promix. The moisture levels of each medium were: no applied water, moderately watered (between wilting point and field capacity), and field capacity, which represented moisture tension levels of >–1.5, –0.08, and –0.03 MPa, respectively. Growth from single-node rhizome propagules and large pieces of 5.6 to 7.6 cm long with one or more nodes was determined over 90 days. The large propagules and the field capacity moisture regime produced the tallest shoots, and largest number of shoots and leaves per propagule, as well as the highest percentages of secondary rhizomes, root, and shoots per propagule. The yard waste and Promix were superior to poultry compost in the development of the propagules for all the traits measured. The large propagules produced earlier shoot emergence at field capacity than at the moderate moisture levels. Single-node propagules generally failed to emerge without applied moisture or when in poultry compost.

Excessive amounts of poultry waste on the Delmarva Peninsula of the United States, coupled with the availability of yard waste, may be potential inexpensive nutrient sources for growing vegetables. However, these composts may contain unsafe microorganisms. This study, therefore, was conducted to determine the presence and persistence of biological agents in soil treated with poultry compost and yard waste. Tatsoi [Brassica rapa (Narinosa Group)] and spinach (Spinacia oleracea L. `F415' and `Seven R') were planted under a high tunnel to extend their fall growing season. Samples of soil–compost mixture and original poultry compost were collected once a month for 4 months. Escherichia coli O157:H7 in the samples was determined by enrichment and immunomagnetic separation, and was not detected in any of the soil-mixtures. However, this bacterium was detected in the original poultry compost in very low numbers. Plant leaves were harvested periodically. Results showed that tatsoi plants significantly produced larger leaves and higher fresh weight in soils amended with organic compost with the tendency for yield to increase with the increase in harvest date. Generally, the organic amendments did not influence size and total fresh weight of spinach leaves, although earlier harvests tended to produce significantly larger leaves and higher fresh weight.