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SWEET CORN VARIETIES OF DIFFERENT GENETIC TYPES RESPOND SIMILARLY TO NITROGEN FERTILIZATION

Mullins et al. (page 32) found that 100 lb/acre of nitrogen was adequate for production of `Silver Queen' (normal sugary type), `Incredible' (sugary enhanced type), and `Challenger' (shrunken-2 type) sweet corn varieties. `Silver Queen' produced the most attractive ears. `Challenger' produced smaller ears that were most suitable for boxing for fresh market shipment. There was little visible ear difference between 50, 100, and 150 lb/acre of nitrogen per acre. Ammonium nitrate was applied preplant except for the 150 lb/acre rate where 100 lb was preplant and 50 lb was sidedressed.

JUNIPER VARIETIES SUITABLE FOR LANDSCAPE PLANTING IN SOUTHERN ROCKY MOUNTAINS

Increasing population growth and restricted water supplies have put pressure on the landscaping industry to develop and install attractive xeriscape landscapes in the southern Rocky Mountains. A 20-year field trial reported by Harrington and Fisher (page 40) evaluated the performance of 34 juniper varieties. A wide range of juniper varieties, representing a diversity of crown shapes, foliage colors and overall sizes were found suitable for the low maintenance, xeriscape market in the southern Rocky Mountains.

OPTIMIZING SOIL MOISTURE MAY EXTEND ASPARAGUS HARVEST SEASON

Many attempts have been made to extend the growing season of asparagus in temperate regions. Most efforts have failed due to a loss of plant vigor and yield. A new production technique, reported by Reiners and Garrison (page 45), offers some hope. Rather than cutting all the spears in the spring, the motherstalk method allows for some spears to develop mature ferns. This permits harvest of later developing spears and extends the harvest period. Growers may need to optimize soil moisture to maximize the potential of this method. Asparagus grown in dry soils had significantly reduced yield compared to treatments where soil moisture was optimum.

PRECISION OF VEGETABLE SEEDERS VARIES WITH SEED SPACING

Previous studies revealed unexpected variation in seed spacing uniformity of precision vegetable seeders. Bracy et al. (page 47) evaluated belt and vacuum seeders using cabbage seeded at different seed spacings to determine if seeder uniformity was affected by seed spacing. Seeding uniformity of the belt seeder was not affected by seed spacing, but seeding uniformity of the vacuum seeder improved as seed spacing increased from 1.5 to 11 inches. Seed singulation and spacing of the vacuum seeder were not considered adequate for a precision seeder. Overall, seeding uniformity was better with the belt seeder than the vacuum seeder.

FRUIT QUALITY OF NAVEL ORANGE NOT AFFECTED BY LATE NITROGEN FERTIGATION

Kallsen (page 51), in California, found no differences in fruit quality characteristics among plots of drip-irrigated trees in which the last nitrogen fertigation varied from 1 May to 1 August for November-harvested fruit. Characteristics measured included the soluble solids/acid ratio, time to color break, and fruit diameter. The results suggested that the seasonal nitrogen requirement of the orchard may be applied over most of the growing season without affecting the maturity or the final size of the orange.

PRIMED SEEDS DO NOT ENHANCE GREENHOUSE PRODUCTION OF MUSKMELON TRANSPLANTS

Earliness and uniformity are important characteristics in transplant production. Although muskmelon seeds will germinate over a range of temperatures, temperatures that are divergent from the optimum range result in slow, irregular, or low germination. Nascimento and West (page 53) reported that although the use of primed seeds in muskmelon transplant production caused no beneficial effect on seedling development, primed seeds may give better results than raw seed in terms of germination performance, particularly where the transplant grower cannot control germination conditions within narrow ranges.

PREPLANT COPPER-BASED COMPOUNDS REDUCE ERWINIA SOFT ROT IN CALLA LILIES

The control of bacterial soft rot is essential for greenhouse growers to force field grown calla lilies successfully either as a pot plant or as a cut flower. Commercially, rhizomes are treated with a sterilant/bactericide before planting. A number of sterilants, applied as a preplant dip to calla rhizomes, were compared by Blom and Brown (page 56). Copper-based sterilants such as Fixed Copper or Phyton-27 proved to be more effective in controlling the bacterial soft rot than either Physan-20 or Virkon.

FERTILIZER CHOICES IN HYDROPONIC CROP PRODUCTION

Reducing the supply of nutrients to plants grown in hydroponic systems is desirable to decrease environmental pollution and fertilizer costs. Papadopoulos et al. (page 59) report that as the supply of macronutrients is reduced, it is possible to add other salts that are financially and environmentally more acceptable to raise the electrical conductivity of the nutrient solution to appropriate levels. Greenhouse tomatoes were grown in the NFT (nutrient film technique) hydroponic system by partially substituting macronutrients in the recirculating solution with potassium sulfate or sodium chloride without detrimental effects on growth, yield, or fruit quality.

PEACH HARVEST NOT DELAYED AND FRUIT SIZE NOT REDUCED BY ETHREL

Ethrel sprayed in late autumn can enhance peach flower bud survival to late spring frosts by increasing cold hardiness and delaying bloom. Reports indicate that Ethrel can alter cropload, and thus affect fruit size at harvest. In addition, some researchers have observed that Ethrel may delay harvest date, but the compounding effect of Ethrel on cropload was not removed from these studies. Ebel et al. (page 65) demonstrate that when the cropload of an early-maturing peach variety is adjusted to that of unsprayed control trees, Ethrel does not affect harvest date or fruit weight at harvest.

RAINFALL CAPTURE REDUCES SUPPLEMENTAL WATER NEEDS OF TEXAS CANTALOUPES

The least efficient use of supplemental water for cantaloupe production in Texas is the preplant irrigation used to replenish soil profile moisture. Nearly one third of the total water applied to grow the crop is applied before planting. Dainello et al. (page 78) report that preplant irrigation could be eliminated by capturing rainfall. The system uses a manipulation of conventionally mulched seed beds to enable the capture, concentration and storage of rainfall before planting. Water savings in excess of 30% are achievable.

CULTURE MEDIA FOR GROWING SHIITAKE MUSHROOMS IN VITRO AND ON AMENDED HARDWOOD SAWDUST IN THE GREENHOUSE

Pacumbaba and Pacumbaba (page 85) report the development of several artificial culture media for growing shiitake mushrooms. YMBSA (yeast extract, malt extract, multigrain oatmeal, brown sugar, agar); YVMBSA (yeast extract, V-8 vegetable juice, multigrain oatmeal, brown sugar, agar), and YVMSA (yeast extract, V-8 vegetable juice, multigrain oatmeal, sucrose, agar) were used to produce flocculent mycelial growth in 20 days and induced basidiocarps 35 days later in petri dishes.

In addition, Pacumbaba and Pacumbaba (page 91) created broths to amend hardwood sawdust for spawn production in 35 to 45 days in P4928 culture containers: YVMBS (yeast extract, V-8 vegetable juice, multigrain oatmeal, brown sugar); YVMS (yeast extract, V-8 vegetable juice, sucrose); and MVBS (multigrain oatmeal, V-8 vegetable juice, brown sugar). Amended hardwood sawdust inoculated with spawn of shiitake mushroom produced basidiocarps from one to three months after inoculation in the greenhouse.

CESSATION OF BLOOM DURING HIGH TEMPERATURES INFLUENCES MARKETING SEASON FOR SPECIALTY FLORAL CROPS

High temperatures reduce the flowering performance of some specialty floral crops; therefore, these species should be marketed as spring-flowering products in some climates. The effects of increasing temperatures on the duration of postharvest flower development was determined in three specialty crop species. Williams et al. (page 94) observed that marguerite daisy (Argyranthemum frutescens) varieties `Butterfly' and `Sugar Baby' flowered best when the average daily temperature was below 82 °F. Bacopa (Sutera cordata) `Snowflake' and swan river daisy (Brachycome hybrid) `Ultra' flowered best when the average daily temperature was below 73 °F.

AUXIN AND WOUNDING INCREASE ROOTING OF PRICKLY-PEAR CACTUS CLADODES

Lazcano et al. (page 99) report that the use of auxin [indole-3-butyric acid potassium salt (K-IBA)] and certain wounding methods enhanced rooting of prickly-pear cactus cladodes. Greater root numbers were obtained at higher auxin concentrations and with wounding methods that had the greatest cut surface area. This observation validates the commercial practice of allowing cladodes to suberize early in the propagation cycle. K-IBA altered rooting polarity and stimulated adventitious root formation along the wounded cladode surfaces. Vertical non-suberized wounding methods and auxin treatments are an excellent classroom demonstration for manipulating rooting polarity. Auxin application and wounding could be of commercial benefit for enhanced rooting in the clonal regeneration of new selections for prickly-pear cactus orchards.

A DEVICE FOR MEASUREMENT OF STRAWBERRY FIRMNESS

Transport and handling tolerance is an important quality factor of strawberries. Different methods are used to assess fruit firmness and determine handling tolerance. Hietaranta and Linna (page 103) describe a penetrometric method using a motorized, materials testing device. Three parameters were measured using this method: maximum force, mean force, and instant of yield point. Maximum force provided the best assessment of strawberry fruit firmness.

ESTIMATING APPLE FRUIT DIAMETER FOR TIMING CHEMICAL THINNER APPLICATIONS

The efficacy of chemical thinning applications is influenced by the average diameter of apples at application time; however, measuring many fruit with calipers is expensive. Marini (page 109) sampled fruit of several strains of `Delicious' and `Golden Delicious' from several orchards for 3 years to develop a model to accurately estimate average fruit diameter from fruit weight. To estimate fruit diameter for a block of trees, a random sample of 100 fruit (pedicels attached) was weighed, and the average fruit weight was calculated by dividing the total weight by 100. Values for average fruit diameters, ranging from 2.7 to 28.2 mm, estimated from fruit weights are presented in a table (page 113).

INTERACTIVE TELEVISION IS A VIABLE ALTERNATIVE TO FACE-TO-FACE MASTER GARDENER TRAINING

Constrained budgets and faculty resources often limit efforts to deliver Master Gardener training and to maintain or expand the volunteer program. Warmund and Schrock (page 116) report that participants trained at multiple sites via interactive television rated the training slightly less favorably than those trained face-to-face. Technological shortcomings (sound and slide quality) of interactive television were identified by participants as difficulties; however, most of these problems are easily correctable. While face-to-face training was slightly preferred by participants, instructor availability, limited travel budgets and time constraints make interactive television program delivery attractive to Master Gardener instructors and administrators.

`MARIANNA 2624' PLUM AS A ROOTSTOCK FOR ALMOND

Not all almond varieties are compatible on `Marianna 2624' plum rootstock; however, growers sometimes prefer this rootstock because of its tolerance to armillaria root rot and heavy, wet soil. To overcome this incompatibility problem, interstocks of `Havens 2B' have been used. Edstrom et al. (page 127) report that longer interstocks (8-10 inches or scaffold budding) performed better than shorter interstocks (4 inches) of `Havens 2B'. Longer interstocks of compatible almond varieties also appeared promising.

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