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CARDY NITRATE AND SPAD CHLOROPHYLL METERS PROVIDE EFFECTIVE IN-FIELD NITROGEN TESTS FOR VEGETABLE CROPS

Vegetable growers would benefit from rapid in-field tests to improve nitrogen (N) use efficiency. Westerveld et al. (p. 179) examined the potential of Cardy nitrate and SPAD chlorophyll meters in three vegetable crops. The Cardy nitrate meter test was straightforward, inexpensive, and effectively indicated leaf nitrate concentrations. On cabbage and onions, the SPAD chlorophyll meter test was straightforward, inexpensive (compared to 100 or more laboratory tests), and effectively indicated leaf total N concentrations. For field N management, a well-fertilized reference plot is most appropriate for the SPAD chlorophyll meter, whereas critical nitrate concentrations would be required for the Cardy nitrate meter.

PROMISING ALTERNATIVES TO ENDOSULFAN FOR BLUEBERRY MITE CONTROL

The blueberry bud mite can cause significant damage to blueberry plantings. Endosulfan is the main chemical used for control, but this product is being evaluated for safety concerns and its use may be restricted in the future. Laboratory evaluation of miticides by Isaacs et al. (p. 188) indicated that abamectin and oil, in combination or separately, are both highly effective alternatives. In the field, mite populations were reduced by application of oil in the spring and by postharvest application of endosulfan, indicating that chemical control of bud mite is possible with conventional and organic options.

MYCORRHIZAE RESPOND TO USE OF ORGANIC AND INORGANIC FERTILIZERS

High levels of fertilizers inhibit arbuscular mycorrhizae (AM), especially those with high phosphorus (P) content. Linderman and Davis (p. 196) found that organic fertilizers, that release nutrients slowly as a result of microbial degradation of substrates, generally were more compatible with AM than controlled-release (prilled) inorganic fertilizers, unless the P level of the latter was low. However, onion or miniature rose shoot growth was less with organic than inorganic fertilizers, and was only increased when inoculated with the AM fungus Glomus intraradices.

PRODUCING WOODY FLORAL PRODUCTS IN AGROFORESTRY PLANTINGS.

Producers in the central United States are showing considerable interest in growing alternative crops for supplemental income. Woody floral products, such as curly willow, pussy willow, red-stemmed dogwoods and many others show considerable potential. Josiah et al. (p. 203) describe the results of field trials, and labor and financial investigations of woody floral production in a conservation planting in Nebraska. While financial returns varied among species and varieties, net returns for several varieties were substantial. Overall findings indicate that commercial production of selected varieties of woody florals in an agroforestry configuration can be a profitable alternative to using conventional woody species.

ECOLYST EFFECTS ON JUICE SOLUBLE SOLIDS (BRIX) OF ORANGES AND GRAPEFRUIT

EcoLyst has been shown to increase juice Brix of oranges, but results have been variable, possibly due to differences in time of application. Davies et al. (p. 207) applied EcoLyst at various times from prebloom to initial fruit set to several orange and grapefruit varieties. EcoLyst increased juice Brix in 5 of 13 trials for oranges and 1 of 5 trials for grapefruit. Optimum application time ranged from prebloom to 25% open flowers. In general, EcoLyst effectiveness for increasing juice Brix of oranges and grapefruit was less than previously reported.

LANDSCAPE EFFECTIVENESS OF PINE BARK SOIL AMENDMENT IMPROVED BY ADDITION OF NITROGEN OR COTTON GIN WASTE

Urban soils found at construction sites are frequently less than ideal for landscape plantings due to the removal of native topsoil. Ground pine bark is often used to amend the soil in an attempt to improve landscape beds. Sloan et al. (p. 212) found that in a clay soil the addition of nitrogen or cotton gin waste to pine bark amendment resulted in improved plant growth of pansy, vinca, and crapemyrtle compared to pine bark alone. In some instances pine bark amendment alone without added nitrogen or cotton gin waste suppressed plant growth.

EFFECT OF LEAF EXTRACTS AND A SOIL AMENDMENT ON RECEMENTATION OF CRUSHED ORTSTEIN

Ortstein, a type of hardpan, inhibits blueberry growth and reduces production. Bronick et al. (p. 218) found that crushed ortstein in soil columns was recemented by blueberry leaf extract in less than 1.5 weeks. Bent grass and fescue leaf extracts also produced recementation, but less than blueberry. Strengths of recemented ortstein from blueberry and bent grass treatments were greater than that of fescue treatment and similar to that of uncrushed ortstein. Addition of a soil amendment, Super Symbex 4X, tended to prevent recementation of crushed ortstein and reduced the strength of uncrushed ortstein pieces.

STRAWBERRY TOLERANCE OF TERBACIL IS ENHANCED BY TIMING AND POST-APPLICATION IRRIGATION

Weeds control options for strawberries are limited due to the crops' sensitivity to herbicides. Polter et al. (p. 223) applied terbacil to strawberry plants at recommended and 2× rates. Herbicides were applied to dormant plants, and plants at the three- and six-leaf stages. Dormant plants were not injured, but rate-dependent injury occurred when the herbicide was applied at the three- and six-leaf stages. `Mira' strawberry was more tolerant of terbacil than was `Jewel' or `Allstar'. Washing the foliage with about ½/2 inch of water, up to 4 h after terbacil application, reduced injury to acceptable levels.

DECIDUOUS HOLLIES PROVIDE LONG-LASTING BRANCHES FOR INDOOR AND OUTDOOR DISPLAYS

According to a study by Jones et al. (p. 230), winterberry and japanese winterberry branches held in distilled water maintained berry shine and overall branch quality (i.e., marketability) for 4 to 5 weeks. Preservative solutions enhanced the quality of the berries, and storage at 32° F had little detrimental effect on branch vase life. Cut branches of all varieties had an even longer display life when stuck in moist sand and evaluated outdoors. Deciduous holly branches with their vivid red and orange berries provide an attractive alternative cut branch for both interior and outdoor holiday displays.

CONVENTIONAL AND ORGANIC GREENHOUSE PRODUCTION OF FRESH BASIL

Fresh basil is in demand from specialty markets and restaurants. Succop and Newman, (p. 235) describe three media, fertilized conventionally or organically, for greenhouse production of basil. Basil yield was greatest when plants were grown on a sphagnum peat/perlite/compost substrate, compared to plants grown on rockwool or perlite The yield was similar between conventional and organic fertilizer. Yield for plants grown on perlite was greater with organic fertilizer compared to conventional; whereas, yield for plants grown on rockwool was greater with conventional fertilizer. The optimum growing medium for fresh basil, is that which best fits existing greenhouse conditions and market.

CUCUMBER VARIETIES CAN RESIST FUSARIUM ROOT AND STEM ROT DEVELOPMENT

Fresh market cucumbers grown under greenhouse conditions are affected by a number of important fungal diseases, such as fusarium root and stem rot (FRSR). This disease was first reported in Greece and Holland, and now occurs in greenhouses in Canada, France, Israel, and the U.S. Rose and Punja (p. 240) screened 18 Englishtype cucumber varieties for resistance. Three varieties demonstrated a high degree of resistance after 4-8 weeks. The varieties most commonly grown in Canada were highly susceptible, indicating a need to develop varieties with enhanced resistance to FRSR.

CONTROL OF KILLED MULCHES ESSENTIAL TO THE USE OF CONSERVATION TILLAGE FOR ORGANIC PROCESSING TOMATO PRODUCTION

Organic growers may use cover crops to increase soil organic carbon (SOC). However, tillage operations used to incorporate the cover crop also can lead to increased microbial degradation of SOC and carbon loss in the form of CO2. Conservation tillage (CT) may provide an answer to this paradox; however, Madden et al. (p. 243) suggest that in order for organic CT to work, growers must select for cover crop varieties that do not regrow after being mowed and that breakdown easily to allow for any necessary late-season cultivations.

APPROPRIATE HARVEST AND STORAGE PROGRAMS FOR `CONCORDE' PEAR

`Concorde' is a new pear variety of considerable interest in Washington. Drake et al. (p. 250) found that mature `Concorde' pears (13 lbf flesh firmness) can be harvested over a 14-day period with good poststorage quality. Regardless of harvest date within that 14-day window, `Concorde' fruit should not be stored longer than 90 days in regular atmosphere storage or 180 days in controlled atmosphere (CA) storage. For best fruit quality, oxygen in the CA storage should be held at or above 1.5% and carbon dioxide at less than 1.0%.

EFFECTIVE USE OF AN INEXPENSIVE GARDEN SEEDER IN RESEARCH PLOTS AND GARDENS

An inexpensive garden seeder can deliver adequate seeding uniformity for use in research and demonstration plots as well as gardens. Parish and Bracy (p. 257) evaluated an Earthway seeder with 18 species of vegetable seeds using standard metering plates, optional plates, and plates modified by closing some cells with tape. Although the seed spacing uniformity was not as good as can be obtained with a precision vegetable seeder, precision seeders cost more than 10 times as much as the garden seeder. Seed spacing uniformity was measured. A table of recommendations for use of the seeder is provided.

APPLES STORED AT THE MOST BENEFICIAL OXYGEN LEVELS USING CHLOROPHYLL FLUORESCENCE

HarvestWatch is a non-destructive, real-time, chlorophyll fluorescence-based technology that identifies the transitional threshold between aerobic and anaerobic metabolism in apples in low-oxygen storage by a spike in the fluorescence parameter (F'). Apples are conventionally stored at prescribed, static oxygen regimes that are relatively distant from oxygen settings that induce anaerobic metabolism. DeLong et al. (p. 262) show that apples can be successfully stored at dynamic oxygen levels set 0.1% to 0.2% above the anaerobic threshold, resulting in firmer, superficial-scald-free fruit that do not incur anaerobically induced injury or off-flavors.

COST-EFFECTIVE PLANTING OPTION AIDS SWITCH TO HIGH-YIELDING CRANBERRY VARIETIES

To remain economically competitive, Massachusetts cranberry growers are renovating existing beds to high-yielding varieties. Renovation is very expensive and growers must minimize costs while maximizing successful establishment of new vines. Sandler et al. (p. 267) conducted an economic analysis of 48 different combinations of nitrogen rate, vine density, and weed management option. The most cost-effective production scheme for a vigorous hybrid was to plant vines at low density, use moderate rates of nitrogen, and apply an annual application of a preemergence herbicide. More expensive, nonchemical combinations could be utilized if growers are properly positioned in the organic market.

ECONOMICS OF FRUIT THINNING IN APPLE AND CITRUS

Fruit thinning is widely practiced to control alternate bearing and increase fruit size. Davis et al. (p. 282) reviewed the literature related to the economics of thinning apple and citrus. Very few studies attempted to evaluate the economic implications of cropload, but the few economic studies summarized in this review illustrated that the economic effects of fruit thinning vary widely and successful thinning often reduces returns to the grower. It is important to quantify the economic benefit of thinning and identify croploads that provide optimal crop value.

FRESH MARKET CABBAGE VARIETIES FOR SUBTROPICAL REGIONS

In many tropical and subtropical areas, one cabbage variety may dominate the market for a decade. The slow process of variety replacement partially is due to the lack of rigorous independent evaluation of alternative varieties with similar consumer acceptance and superior horticultural traits. Morales-Payan and Stall (p. 295) compared cabbage varieties to the standard, `Izalco,' in a cool subtropical region (14.7 to 25.0 °C) in the Dominican Republic. Yield, earliness, head attributes, damage by diamondback moth larvae, and consumer preference were evaluated. `Green Cup,' `Blue Vantage,' and `Genesis' were comparable or superior to `Izalco.'

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