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- Author or Editor: D. W. Kretchman x
Transplants of `Ohio 8245' tomato grown in 48-cell plastic trays received 5 potassium chloride concentrations and were stressed by withholding water during the 6th week of growth. Gravimetric water loss differed between treatments with decreased water loss associated with increased potassium chloride concentration. As water was withheld, incidence of wilt was greater and more evident at an earlier stage with plants supplied with lowering KCL concentrations. Root and shoot dry weights, plant height and leaf area were not affected by treatments. This indicates an apparent increase in water use efficiency in tomato transplants supplied with KCL at greater concentrations than supplied under standard fertilizer regimes.
Two cultivars of tomato (Lycopersicon esculentum) and leaf lettuce (Lactuca sativa) were evaluated using two plug trays, polyethylene and polystyrene in two colors, black and white. Cells were 2 cm square inverted pyramid and 5 cm deep. Temperatures 0.3 cm below the surface of the media in the black trays average 2 to 4°C warmer than in the white trays. Night temperatures were not influenced by tray color. There was no apparent interaction between color and tray composition. Tomato plants grown in black trays had longer, smaller diameter stems than those in the white trays. Total leaf area, plant fresh and dry weights, however, were not affected by tray color. Leaf lettuce grown in black trays had greater total leaf area than those in white trays. Leaf numbers were not affected by tray color. Plants of tomato and lettuce grown in white trays were shorter, stockier, and easier to handle during transplanting than those produced in black trays. Both cultivars of tomato and lettuce responded similarly to tray color and composition.
Germination inhibitors found in parsley (Pertroselium hortense) seed have serious effects on field establishment. Studies have been conducted on chemical and physical attributes in relation to cultivar, age of seed and location of the seed on the seed stalk. Results indicate that the inhibitor is highly soluble in H2O and can be removed with as little as a half-hour aqueous wash. Soaking 30 g (∼500 seeds/g) of seed in an aerated graduated cylinder containing 100 ml distilled H2O for 24 hours then applied to radish, lettuce, and parsley seeds revealed complete germination inhibition of these seeds. Decreasing the soaking time did not reduce the inhibitory effects of the solution. Location of the inhibitor within the seed was found to be specific to the seed coat. The amount of inhibitor present varied with the cultivar and seed lot within that cultivar. Size and age of the seed had little effect on the amount and strength of the inhibitor. Location of the developing seed on the seed stalk effected the amount of inhibitor present. Primary umbels contained the least amount of inhibitor when compared to the secondary and tertiary umbels.
Abstract
Three weeks after transplanting tomato plants (Lycopersicon esculentum Mill.), aqueous sprays of dikegulac were applied at concentrations of 0, 100, 500, and 2500 ppm to stimulate lateral branching. An apical hand-pinch pruning treatment also was made at this time. Ten days later, a separate 500 ppm dikegulac treatment was applied. An increase in the degree of lateral branching was observed with the 500 and 2500 ppm dikegulac concentrations. The hand-pinched treatment had no apparent influence on branching. The stimulation of branching increased the total number of fruiting clusters per plant. However, the 2500 and late 500 ppm dikegulac treatments delayed flowering, delayed fruit maturity, reduced fruit size, and restricted yields. The 100 and early 500 ppm dikegulac and hand-pinch treatments had no apparent effect on yields or time of fruit maturity. Chemical name used: 2,3:4,6-bis-O-(1-methyl-ethylidene)-α-L-xylo-2-hexulofuranosonic acid (dikegulac).
Abstract
After the major fruit set period was completed, aqueous sprays of 1000 ppm dikegulac, 66 ppm ancymidol, 1000 ppm maleic hydrazide (MH), and 1 kg·ha−1 RSW 0411 were applied to processing tomato (Lycopersicon esculentum Mill) plants. Dikegulac, RSW 0411, and ancymidol visually reduced vegetative growth, whereas MH had no apparent influence. None of the compounds reduced the number of flower clusters or flowers per cluster on the late-season growth, but dikegulac and RSW 0411 did reduce the percentage of fruit set in the terminal regions. The partial reductions in late vegetative and/or reproductive growth from the chemical treatments did not enhance uniformity of fruit maturity. Only the dikegulac treatment decreased the yields and percentage of green fruit from the harvest. Chemical names used: 2,3:4,6-bis-O-(1-methylethylidene-d-l-xylo-2-hexulofuranosonic acid (dikegulac); α-cyclopropyl-α-(4-methoxyphenyl)-5-pyrimidinemethanol (ancymidol); 1,2-dihydro-3,6-pyridazinedione [maleic hydrazide (MH)]; and β-(cyclohexylmethylene-α-(1,1-dimethylethyl)-1H-1,2,4-triazole-1-ethanol (RSW 0411).
Abstract
‘Heinz 2653’ and ‘Heinz 722’ tomatoes (Lycopersicon esculentum Mill.) were grown at four plant populations (21,530, 28,700, 43,050, and 57,400 plants/ha) in both single and twin rows. Plant density had no influence on ripe fruit yields of ‘H-2653’. The twin-row configuration did result in increased yields from ‘H-2653’, but not ‘H-722’. Density had no influence on yield of ‘H-722’ in 1984, but yield was reduced at the highest density of the twin-row configuration in 1983. Shoot dry matter, ripe fruit yields, and total yields per hectare of ‘H-2653’ were higher from the twin rows than from the single rows. There were no yield advantages for ‘H-722’ in twin-row arrangements. The ‘H-2653’ yield increases in twin rows were due to an increase in number of ripe fruit per plant. As population pressures increased, the number of ripe fruit per plant, ripe fruit size, and clusters per plant decreased. Plants grown in twin rows covered a greater percentage of their allotted space than those in single rows, regardless of cultivar. As the population density increased, the canopy coverage also increased. Plants at high densities and those in twin-row arrangements intercepted more light than those at low density and single-row plantings.
Abstract
The rate of increase in vine length and node number of fruiting plants of cucumber (Cucumis sativus L.) was reduced after 1 week of water stress and completely inhibited after 2 weeks. Control plants also experienced a reduction in growth rate of vine length and node number but not as pronounced as in the stressed plants. Fruit growth rate was severely reduced in water stressed plants, however, the larger fruits were less affected than the smaller ones. Osmotic and water potentials were lower in the large stressed fruits than in the small stressed fruits.
Abstract
A definite flavor preference resulted from slices of ‘Delicious’ and ‘Golden Delicious’ apple (Malus domestica Borkh.) impregnated with cherry and black raspberry juices. Color ratings of these slices were also acceptable and were nearly identical to the control, impregnation with 40% sucrose syrup. In general color and texture scores were higher from slices processed from non-stored apples than those stored for 6 and 12 weeks. Texture was not influenced by impregnation treatments.
Abstract
Defoliation of transplants of tomato (Lycopersicon esculentum Mill.) at planting delayed plant development (including fruit maturity), but leaf areas of defoliated and nondefoliated plants were equal at fruit maturity. Defoliation at first bloom, full bloom, or 2.5-cm fruit diameter resulted in progressively less leaf area at harvest as the degree of defoliation increased. Defoliation of 80% at the above 3 stages of flower/fruit development resulted in reduced yield. Defoliation of 25% or 50% prior to or at full bloom had no apparent influence on yield. However, 25% or 50% defoliation when fruits were near 2.5-cm diameter resulted in yield reduction. Defoliation had no apparent influence on fruit size at harvest. Soluble solids in the fruit were reduced progressively with each successive increase in defoliation, while titratable acidity and pH were not affected. Defoliation increased photosynthesis in remaining leaves 4 and 14 days after treatment but had no effect on transpiration.