I. Chennin Blanc 107-cm bilateral cordon spaced 3.6 × 2.4 m, 1119 vines/ha, 14 spurs with 32 buds/vine. Yields were 8.8 t·ha-1 in the third leaf; 9.7 in the fourth, and 12.8 the 5th year, 1990, at the Jane Terrell Vineyard, Navasota, Tex. II. Cabernet Sauvignon with a two-trunk 122 cm bilateral cordon spaced 3.3 × 1.2 m, 2445 vines/ha with 48 buds/vine. Yields were 9.7 t·ha-1 for 1994 through 1997 at the mechanically harvested Newson Vineyard, Plains, Tex. III. Le Noir with a 91-cm trunk and a two-cane canopy; spaced 3 × 2.1 m, 1536 vines/ha, with 14 buds/vine. Yields were 13.3 t·ha-1 in 1996 and 11.2 in 1997 at Messina Hoff Vineyard, Bryan, Tex. IV. Merlot/110R with a 45° slanting cordon, 30 cm at south to 152 cm at north, spaced 1.5 × 1.5 m, 4308 vines/ha with 10 spurs and 20 buds/vine. Yield of 10.8 t·ha-1 in the third leaf, 1997, at Wolf Vineyard, Valley View, Tex. Four very different canopy systems were successful; the ideal system is yet to be determined.
George Ray McEachern
Richard L. Fery, Blair Buckley, and Dyremple B. Marsh
The USDA, Louisiana State University, and Lincoln University have released a new southernpea cultivar named WhipperSnapper. The new cultivar is the product of a plant breeding effort to incorporate genes conditioning superior yield and seed characteristics of Asian vegetable cowpeas into American snap-type southernpeas. The new cultivar was developed for use by home gardeners and market gardeners as a dual-purpose cultivar that can be used to produce both fresh-shell peas and immature, fresh pods or snaps. Typical ready-to-harvest WhipperSnapper snaps are green colored, 6.4 mm in diameter, 7.6 mm in height, and 24 cm long; the pods are slightly curved at the attachment end. Typical mature-green pods suitable for fresh-shell harvest exhibit an attractive yellow color, are 25 cm long, and contain 14 peas. Fresh peas are cream-colored, kidney-shaped, and weigh 24.5 g/100 peas. Dry pods exhibit a light straw color, and the dry peas have a smooth seed coat. The quality of WhipperSnapper seed is excellent. In replicated field trials, WhipperSnapper produced significantly greater yields of both snaps and peas than the snap-type cultivar Bettersnap. WhipperSnapper has potential for use as a mechanically-harvested source of snaps for use by food processors in mixed packs of peas and snaps. Protection for WhipperSnapper is being sought under the Plant Variety Protection Act.
Gary T. Roberson
Precision agriculture is a comprehensive system that relies on information, technology and management to optimize agricultural production. While used since the mid-1980s in agronomic crops, it is attracting increasing interest in horticultural crops. Relatively high per acre crop values for some horticultural crops and crop response to variability in soil and nutrients makes precision agriculture an attractive production system. Precision agriculture efforts in the Department of Biological and Agricultural Engineering at North Carolina State University are currently focused in two functional areas: site-specific management and postharvest process management. Much of the information base, technology, and management practices developed in agronomic crops have practical and potentially profitable applications in fruit and vegetable production. Mechanized soil sampling, pest scouting and variable rate control systems are readily adapted to horticultural crops. Yield monitors are under development for many crops that can be mechanically harvested. Investigations have begun to develop yield monitoring capability for hand harvested crops. Postharvest controls are widely used in horticultural crops to enhance or protect product quality.
TAM VERACRUZ is a multiple virus resistant (MVR), open pollinated pepper cultivar developed by Texas Agricultural Experiment Station at Weslaco. This pungent, cylindrical (fruit with blunt end and cuticular cracks) jalapeño variety possesses high levels of genetic resistance to several isolates of TEV (Texas, California and Culiacan isolates). It also carries resistance to local virulent isolates of PVY, PeMV, TRSV, CMV, and TMV. This genotype combines the desirable horticultural characteristics of commercial standards and MVR genes derived from PI 342947, PI 264281 AC 2207 and Avelar. Additionally, `TAM Veracruz' has the ability to set fruit at temperatures above 35C. It has a concentrated flower habit, sets fruits earlier and matures more uniformly than its progenitor `TAM Mild Jalapeño-1'. It is predominatly single stemmed and will support a good heavy set of large thick, fruit which can be mechanically harvested. It is well suited for fresh market consumption in salads, or as a processed product, pickled whole, sliced as “nacho” rings or diced for use in picante sauces. This pepper is as hot as Jalapeño M.
Neel Kamal and Christopher S. Cramer
Onions grown in New Mexico are currently harvested manually at 80% tops down (TD). Mechanical harvesting is a matter of urgency for growers in order to remain competitive and to reduce their cost and time. The objective of this study was to find the effect of different harvest stages on bulb quality. Twelve different onion cultivars were sown in Feb. 2004 in Las Cruces, N.M. The experiment was laid out in split-plot design with four harvest treatments based on physiological maturity—20% TD, 80% TD, 1 week after 80% TD, and 2 weeks after 80% TD as whole plots, with cultivars as sub-plots. After curing, data on harvest date, bulb diameter, height, firmness, number of growing points, average center diameter, fleshy scale number, and scale thickness were collected. Maximum number of scales was observed when bulbs were harvested 2 weeks after 80% TD, while average scale thickness was greatest when bulbs were harvested 1 week after 80% TD. Significant treatment by cultivar interaction was observed for bulb firmness. Cultivars Cimarron, Sierra Blanca and NMSU 04-52-2 produced firmer bulbs in all treatments, while NuMex Casper, NuMex Jose Fernandez and NuMex Centric produced firmer bulbs than others, only at 20% TD. Maximum bulb firmness was observed in NMSU 04-28 and NMSU 03-52-1 than others, when harvested 1 or 2 weeks after 80% TD. Overall, bulbs harvested 1 to 2 weeks after 80% TD exhibited firmer bulbs with more scales and greater scale thickness.
W.J. Kender, U. Hartmond, M. Salyani, J.K. Burns, and J.D. Whitney
A field experiment was conducted to determine effects of concentration and spray volume of metsulfuron-methyl as an abscission aid for mechanical harvesting of citrus. Concentrations of 1, 2, and 4 mg·L–1 metsulfuron-methyl were applied to `Hamlin' orange [Citrus sinensis (L.) Osbeck] trees at 470, 1900, and 4700 L·ha–1 (0.5 to 19 g·ha–1 a.i.). Effective fruit loosening was achieved with all applications >1.9 g·ha–1 (4 mg·L–1 at all volumes, 2 mg·L–1 at 1900 and 4700 L·ha–1, and 1 mg·L–1 at 4700 L·ha–1). Heavy defoliation and twig dieback were observed on trees receiving 2 and 4 mg·L–1 at all volumes. Defoliation and dieback became more severe and flower development and fruit set were inhibited as fruit loosening increased. The use of metsulfuron-methyl as an abscission agent for `Hamlin' oranges is not recommended until conditions for its safe application can be determined. Chemical names used: methyl 2-[[[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl) amino] carbonyl] amino] sulfonyl] benzoate (metsulfuron-methyl).
T.K. Hartz, E.M. Miyao, and C. Giannini
Three field trials were conducted in central California in 1999 to assess the effects of transplant production and handling practices on yield, crop maturity, and fruit quality of processing tomato (Lycopersicon esculentum Mill.). For each trial, transplants of `Halley' tomato were obtained from a variety of commercial greenhouse transplant growers and subjected to various conditioning treatments during the week prior to planting. These treatments included N and/or P fertilization, varying temperature exposure or degree of water stress, or storage in the dark for 2 days before transplanting to simulate shipment from greenhouse to field. Nine transplant treatments (combinations of transplant source and conditioning treatment) were evaluated in each trial, with five 30 m long single-row plots per treatment arranged in a randomized complete-block design. Plots were mechanically harvested. Despite large differences among treatments in initial transplant characteristics (plant height, root cell volume, macronutrient content), there were no significant treatment differences in fruit yield in two trials; in the third trial, one treatment had significantly lower yield than the highest yielding treatment. In no trial were treatment differences in crop maturity (percent green fruit) or fruit quality (soluble solids content or juice color) significant. Across trials, the only transplant characteristic positively correlated with relative fruit yield (treatment yield/mean yield of that trial) was shoot P concentration, which varied among treatments from 1.3 to 11.7 g·kg–1.
N. Guner and J.R. Myers
Genetic and morphological characteristics of an architectural mutant in common beans were studied. The mutant had shiny, dark green leaves, overlapping leaflets, short petioles and a terminal reproductive bud even though the line did not carry the fin gene. Branching was nearly absent, resulting in a single stem vine. This is a new form of determinancy in common bean. Inheritance studies demonstrated that the mutant trait was controlled by a single recessive gene. Allelism tests were performed between the mutant and a previously reported similar mutants, which were overlapping leaflets mutant (ol), and dark green savoy leaf mutant (dgs). Results showed that the mutant trait was not allelic to ol and dgs. As a temporary designation, the name “”opiary” describing its compact and neat appearance is being used. Linkage was tested for growth habit (fin), shiny leaf, cross-sectional shape of pods, striped pod (prpst) and pod suture strings (st) with the topiary mutant. No linkages were detected between either the mutant and marker genes or among the marker genes. The topiary mutant has potential for improving common beans. Its single stem growth habit may allow closer row spacing leading to higher planting populations and may enhance the efficiency of mechanical harvest. Pod formation at higher nodes may escape disease. Currently, the thin stems cause lodging. Development of thick and upright forms will be the subject of future studies.
N. Guner and J.R. Myers
Plant breeders are interested in developing upright common beans (Phaseolus vulgaris L.) to reduce diseases and permit mechanical harvest, and improve seed quality. Morphological and genetic characteristics of an architectural mutant in common beans were studied. The mutant had shiny, dark green leaves, overlapping leaflets, and short petioles. Branching was nearly absent, resulting in single stemmed plants. Although mutant plants carried Fin for indeterminacy, and plants progressed in flowering from lower to higher nodes, the terminal node was reproductive. This represents a new form of determinacy in common bean. Inheritance studies demonstrated that the mutant syndrome was controlled by a single recessive gene. Allelism tests between the mutant and overlapping leaflets (ol), and dark green savoy leaf (dgs) showed that the mutant was not allelic to either locus. The trait was designated as Topiary with the gene symbol top, describing its compact and neat appearance. Linkage was tested between top and growth habit (fin), shiny leaves, cross-sectional shape of pods, striped pod (C prpst), and pod suture strings. All genes segregated independently. The genetic merit of the Topiary mutant for improving common beans needs to be investigated, especially the value of single stem growth habit combined with an upright plant habit.
Richard L. Fery
The USDA–ARS has released a new pinkeye-type southernpea cultivar named GreenPack-DG. GreenPack-DG is the first pinkeye-type southernpea to be released that has a persistent green seed phenotype conditioned by both the green cotyledon gene (gc) and the green testa (gt) gene. The new cultivar was developed from a cross between Charleston Greenpack (green cotyledon phenotype) and the breeding line USVL 97-296 (green testa phenotype). Except for longer pods, GreenPack-DG is similar in appearance and maturity to Charleston Greenpack. Dry GreenPack-DG seeds have a richer and more-uniform green seed color than dry seeds of Charleston Greenpack. GreenPack-DG seeds are much less susceptible to color loss due to blanching when harvest is delayed than are seeds of green-cotyledon cultivars such as Charleston Greenpack. Color loss is a critical problem in production systems where preharvest desiccants are used to facilitate mechanical harvesting operations. The 7-day delay between application of the desiccant and initiation of harvesting operations can result in serious color degradation. Results of 3 years of replicated field tests at Charleston, S.C., indicate that GreenPack-DG yields are comparable to Charleston Greenpack yields. The new cultivar has excellent field resistance to blackeye cowpea mosaic virus and does not produce hard seeds. GreenPack-DG is recommended for trial by the frozen food industry as a replacement for Charleston Greenpack. Protection for GreenPack-DG is being sought under the Plant Variety Protection Act.