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  • Author or Editor: M.L. Robbins x
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Abstract

Yields of tomato (Lycopersicon esculentum Mill.) were highest with trickle irrigation, mulching, and staking, but the importance of the individual management components was dependent upon seasonal weather pattern. In 1979, plants that were staked, but not irrigated, produced 78 MT/ha of marketable fruit. Irrigating the staked plants increased yields to 94 MT/ha and to 97 MT/ha if the beds were mulched with black polyethylene. Without staking the plants in 1979, neither trickle irrigation nor mulching influenced fruit yield, which averaged only 45 MT/ha. In 1980, because of a prolonged drought, trickle irrigation increased yields from 33 to 65 MT/ha, mulching increased yields from 42 to 58 MT/ha, but staking did not significantly influence yield. Seasonal water balances suggested that tomato grown on a Norfolk loamy sand should be irrigated before the soil water-tension at the 30-cm depth in the center of the bed exceeds 25 kPa.

Open Access

Abstract

Populations of cabbage looper, Trichoplusia ni (Hubner), and the imported cabbageworm, Pieris rapae (L), generally were about the same on 4 cabbage cultivars treated weekly with a spray mixture containing Bacillus thuringiensis Berliner (45 g/ha) and chlordimeform (1400 g/ha). However, ‘Stein’s Early Flat Dutch’ and ‘Ferrys Round Dutch’ had more plants with uninjured heads and wrapper leaves than did ‘Copenhagen Market No. 86’ and ‘Resistant Golden Acre’. Data suggest complementary effects of host plant natural resistance and the microbial-chemical spray. ‘Stein’s Early Flat Dutch’ was most resistant and ‘Resistant Golden Acre’ was most susceptible, on the basis of the amount of feeding injury.

Open Access

Calcium and magnesium medium requirements were investigated for the production of container-grown `Formosa' azalea irrigated with filtered and unfiltered deep well water. Four inch `Formosa' azalea plants were planted into 3.8 liter containers filled with an amended 4:1(v,v) pinebark:sand growing medium. Calcium and magnesium treatments were supplied by either dolomitic lime or gypsum + epsom salt at three rates. Plants irrigated with good quality water produced excellent quality plants regardless of Ca/Mg treatment. Alkaline well water containing moderate sodium levels inhibited azalea root growth. Medium amended with gypsum + epsom salt produced significantly better quality plants than did medium with dolomitic lime during 157 days of deep well irrigation. Medium pH and Na levels were significantly higher in the control treatment than in the filtered well water treatment. Growth effects of calcium and magnesium treatments were dependent upon water quality and time length of treatment.

Free access

Abstract

A description for the design and use of a flowing solution culture for the mung bean bioassay is presented. A single module for the system is an assembly of polyvinyl chloride (PVC) pipe, Tygon tubing, and 12 hypodermic syringe barrels to accomodate 60 cuttings of mung bean, Vigna radiata (L.) R. Wilcz, (5 per syringe barrel). Solution is circulated by an electric fluid pump. A comparison of this system with conventional vial culture indicates no difference in mean root numbers and their standard deviation, although a more stable solution pH is maintained in the flowing system. In the vial system, pH drifted by as much as 1.4 units within 12 hours, but only 0.2 units in the flowing system. The system presented is ideal for investigations where a stable rooting environment is required.

Open Access

Sodium bicarbonate type irrigation water is detrimental to the growth of Azalea indica `Formosa'. Alkaline irrigation water reduced both top and root growth of `Formosa' azalea. Leaf tissue sodium was significantly greater in azalea plant tissue irrigated with alkaline water. Concentrated sulfuric acid was used to acidify the alkaline water source. Acidification significantly reduced the uptake of sodium into the leaf tissue by 45%. Leaf tissue Ca and Mg levels were significantly greater from plants irrigated wtih deionized water. Azalea plants irrigated with acidified water produced significantly better quality plants. Leaf and root tissue samples were taken after 8 months.

Free access

Abstract

Dime thy letrachloroterephthalate (DCPA) and N,N-dimethyl-2,2-diphenylacetamide (diphenamid) were effective herbicides for sweetpotato on coarse sand soil. DCPA applied through a sprinkler irrigation system proved effective and reduced costs.

Open Access

Abstract

A number of pesticides and growth-regulating compounds were applied to snap and dry beans (Phaseolus vulgaris L.), lima beans (Phaseolus lunatus L.), cowpeas Vigna sinensis (Torner) Savi, and garden peas (Pisum sativum L.) at first bloom in both the greenhouse and the field. Initial increases in pod set were not retained until harvest. Several treatments reduced pot set of snap beans, but none significantly affected yields.

Open Access

Abstract

Of 260 plant introductions (PI) of okra [Abelmoschus esculentus (L.) Moench.] evaluated for disease resistance, 39 were resistant to southern root knot nematode [Meloidogyne incognita (Kofoid & White) (Chitwood)], 9 were resistant to fusarium wilt caused by Fusarium oxysporum f. sp. vasinfectum (A & K) Snyder and Hansen, and 3 were resistant to both. An introduction of A. manihot L., a wild relative of okra, was highly resistant to fusarium wilt.

Open Access

Abstract

‘Beauregard’ sweet potato [Ipomoea batatas [L.] Lam.] was developed by the Louisiana Agricultural Experiment Station to combine resistance to diseases and insects of local importance with good horticultural and culinary characteristics. This cultivar, first designated L82-508, is named after Louisiana's renowned civil engineer and “Napo-lean in Grey,” Gen. P.G.T. Beauregard.

Open Access