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  • Author or Editor: D. E. Johnson x
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Abstract

Cold resistance of primary buds from grapevines (Vitis spp.) decreased with advancing phenological development. Morphological characteristics of canes produced during previous growing season had no effect on bud hardiness at a given stage of development or on development rate when cuttings were forced in the greenhouse. Cultivar differences were found to affect both the rate of bud development and the hardiness at a given stage of buds forced from stored cuttings.

Open Access

Abstract

Five plant species [burford holly (Ilex cornuta Lindl. and paxt. ‘Burfordii’) golden-rain tree [Koelreuteria elegans (Seem. A.C. Sm.], ligustrum (Ligustrum japonicum Thunb.), hibiscus (Hibiscus rosa-sinensis L.), and podocarpus (Podocarpus macrophyllus Thunb.)] were arranged in a 5 × 5 × 5 factorial experiment and sprayed with 4 pesticides (dimethoate, dicofol, malathion, oxydemeton methyl) and water alone, as well as 4 chemicals [ancymidol, ethephon, gibberellic acid (GA3)] and water alone. Growth regulators increased pesticide phytotoxicity ratings, whereas the antitranspirant had no effect on phytotoxicity ratings.

Open Access

Abstract

Increased soil moisture stress reduced growth and transpiration rate of Ficus benjamina. Leaf drop during indoor phase was greater for plants previously watered during production at 3 day intervals than for plants grown under the 6- and 9-day water regimes.

Open Access

Educational and research opportunities utilizing native plant species are being developed by the LSU Agricultural Center through the recent establishment of a native plant arboretum at the Calhoun Research Station. Plants indigenous to Louisiana and surrounding states are being collected and planted in the arboretum for evaluation of potential values for landscaping, in food industries, and/or wildlife management. Native trees being studied include species of oak (Quercus), maple (Acer), hickory (Carya), and dogwood (Cornus). Lesser known species of holly (Ilex) and hawthorn (Crataegus), are being evaluated for commercial production and landscape potential. Fruit being collected for field orchard studies include mayhaw (Crataegus opaca), pawpaw (Asimina triloba), and several native plums (Prunus spp.).

Free access

Abstract

Equal volumes of peanut hulls, pine bark, and sphagnum peatmoss were combined into 5 media. Particle size distribution, total porosity, air space, easily available water, water buffering capacity, and bulk density were determined for each medium. Top dry weight, root dry weight, and percent growth of Rhododendron indicum (L.) Sweet cv. George L. Taber were measured 14 weeks after potting in 1-liter containers. Peanut hulls increased particle size, total porosity, and air space, and decreased easily available water, water buffering capacity, and bulk density of media. Peatmoss generally reduced total porosity and air space and increased easily available water, water buffering capacity, and bulk density regardless of other component combinations. Top dry weight, root dry weight, and percent growth were greater in peanut hull-containing media. Addition of peatmoss to the container media tended to produce less growth.

Open Access

Floral morphology and differentiation of `Sharpblue' southern highbush blueberry (Vaccinium corymbosum L.) were studied under natural growing conditions. There was no rest period during floral development of `Sharpblue' blueberry in Louisiana. Basal florets were already present within a racemic inflorescence in early September. All floral and reproductive organs were clearly visible in early December. Microspores and pollen grains were observed in mid- and late-January, respectively. Megasporocytes, two-cell, four-cell, and seven-cell embryo sacs were found to be simultaneously present in developing ovules in late January, suggesting that megasporogenesis and megagametogenesis in `Sharpblue' blueberry are asynchronous.

Free access

Abstract

Marketable tomato yields were influenced more by applied N than by irrigation. Irrigation increased total marketable tomato yields only at the intermediate level. Average yields for the 3-year period by soil water regimes were about 58,300, 70,000, and 68,900 kg/ha for no, intermediate, and high irrigation, respectively. Applied N increased yields, but the increase was limited mainly to the lowest application rate (65 kg/ha) in 1971 and 1972, and to the 2 lowest rates (65 and 130 kg/ha) in 1973. Average yields for the test period by N application rates were about 53,500, 67,100, 69,900, 70,600 and 67,600 kg/ha for 0, 65, 130, 195, and 260 kg/ha rates, respectively. These data indicate that the best combination of N rate and soil water regime was 65 to 130 kg/ha of applied N and supplemental irrigation as needed to maintain 30% or more available water in 0 to 60 cm soil depth.

Open Access

Abstract

‘Red-N-Sweet’ is a high quality, Vermillion red-fleshed watermelon for local markets and home gardeners. Fruit reaches maturity in about 85 days from seeding. This cultivar has shown good field resistance to fusarium wilt [Fusarium oxysporum sp. niveum (E.F. Sm.) Snyder and Hansen].

Open Access

Abstract

‘Royal Blackeye’ southernpea [Vigna unguiculata (L.) Walp.] was released in 1985 by the Louisiana Agricultural Experiment Station. This southernpea was developed primarily for local fresh market use. The purple hulls and blackeye seed coat pattern combination is unique among released cultivars.

Open Access