Search Results
Perennials grown in 5.7-cm containers received two root treatments (mechanical root-pruned and non-pruned) prior to field planting. During the 1996 season, the two root treatments and five irrigation treatments, (0%, 25%, 50%, 75%, 100%) ET0 (reference crop evapotranspiration), were tested on Delosperma cooperii, Delosperma nubigenum, Polygonum affine, and Veronica liwanensis and evaluated on the basis of plant growth and visual ratings. No significant change in height occurred in any species for both root or irrigation treatments. No significant change in width or density occurred in D. cooperii, from root treatment; however irrigation treatments below 50% resulted in a significant decrease in width. Significant deceases in width also occurred in all species from irrigation treatments. Mechanically root-pruned plants resulted in a significant decrease in density of D. nubigenum, P. affine, and V. liwanensis and a decrease in width in P. affine.
Seven Vaccinium angustifolium clones were tested for low-temperature tolerance over two dormant seasons. Flower primordia in the pseudoapical bud were damaged at higher temperatures than were stem tissue and primordia of the fourth floral bud. The flower primordia located at the stem tip also reacclimated earlier and seemed to show a stronger response to abrupt spring warming than did other tissues tested. Given the lowest survival temperatures determined and the ambient temperatures recorded, we recommend that the physiological and economic aspects of cryoprotectants and flower-delaying treatments be studied further.
Nine treatments, arranged in a RCB design with 4 replications on 20m rows/plot, were all soiled applied and incorporated under black polyethylene mulch, prior to planting. The treatments were: methyl bromide (MB) 98 and 67 & chloropicrin at 168 kgha-1, metham sodium at 17 & 34 1ha-1, oxamyl at 1.6 & 3.21 1ha-1, fosthiazate 6.5 & 13 kgha-1, and a control. Four week-old `Crimson Sweet' watermelon (Citrullus lanatus) transplants were established 3 weeks after chemical applications were made. Soil samples were taken in the plastic row-middle, plastic edge, 30 cm off the plastic edge and 15, 30 & 45 cm deep at each sampling location 3 and 6 weeks after transplanting. The presence of Root-knot Nematode, RKN, (Meloidogyne spp.) was established by using `Mountain Pride' tomato as a bioassay. Fruit size and total yield were recorded and the economic return for each control practice calculated. The 1.6 1ha-1 oxamyl plots yielded 6,832 kgha-1 more than the control which corresponds to a return of $183 for the investment of that control. The 3.2 1ha-1 plots had a yield increase of 7,728 kgha-1 and a return of $103, followed by, in order of yield response, 17 1ha-1 Metham plots, 18,592 kgha-1 & $498, 34 1ha-1 Metham plots, 25,872 & $693, MB 67 plots, 35,952 kgha-1 & $752, and MB 98 plots, 37,072 kgha-1 & $851.
Muskmelons (Cucumis melo L. cv. Superstar) were grown at two between-row spacings (1.5 m or 2.1 m) and four in-row spacings (0.6, 0.9, 1.2, or 1.5 m), corresponding to populations from 3074 to 10763 plants ha-1, to determine the influence of row spacing and population on melon growth and yield. The study was conducted at two sites in 1993, one in northern and one in southern Indiana. Numbers of flowers and early season vine growth were not significantly different between treatments. In southern Indiana, the number of fruit harvested per plot increased as in-row spacing decreased; means ranged from 5.2 fruit plot-1 for 0.6 m in-row spacing, to 4.7 fruit for 0.9 m in-row spacing, 3.9 fruit for 1.2 m in-row spacing, and 3.3 fruit for 1.5 m in-row spacing. Harvests were significantly earlier for the 0.6 m in-row spacing. Mean melon weight was significantly greater for 1.5 m in-row spacing, averaging 4.1 kg, compared to 3.8, 3.7, and 3.7 kg for 0.6, 0.9, and 1.2 m in-row spacings, respectively. Between-row spacing did not affect number or weight of melons. There were no significant interactions between in-row and between-row spacings.
Abstract
Methomyl insecticide (Lannate 90 wp) was selectively phytotoxic on hybrids and inbreds of sweet com (Zea mays L.) having the Texas male sterile cytoplasm (T-msc). In field and greenhouse tests, phytotoxicity was visible at leaf tips and margins 2 days after a foliar application of 300 ppm methomyl. In the greenhouse, a pre- or postemergence application of methomyl, 75 mg/kg soil resulted in severe necrosis, chlorosis, and eventual death of the seedlings. None of 100 hybrids and inbreds with normal cytoplasm and 4 other different sources of sterile cytoplasm showed any visible injury following a foliar or soil application of methomyl.
Field and laboratory experiments were conducted to study the effect of soil applied (Carbofuran) Furadan on watermelon and cantaloupe yields. Yields were significantly (p≤ 0.05) greater when Furadan was used than when it was not. The observed yield increases may have been due to factors other than just the insecticidal properties. Other systemic insecticides demonstrated no similar increase in yield. Yield increases were also evident even when plants were grown in sterile soil. Yield increase was due to a significant increase in the first harvest of watermelon and the first three harvests of cantaloupe. Numbers of fruit and average wt/fruit were increased for watermelon at the first harvest. Midwest growers usually receive the highest price per pound of watermelon at the first harvest. This significant increase in early harvest more than pays for the application of the chemical.
Muskmelon (Cucumis melo L. cvs. Superstar and Mission) transplants were grown in seedling flats with individual cells ranging in volume from 7 to 100 cm3. The smallest cells were in a 338-cell polystyrene flat 33 cm wide × 66 cm long × 4.75 cm deep; the largest cells were in a 32-cell plastic flat 30.5 × 50.8 × 6.5 cm. The study was conducted in Florida and Indiana during the 1993 and 1994 growing seasons. Seedlings of uniform age were transplanted to the field and grown to maturity using standard cultural practices. Early yield of `Superstar' muskmelon, measured as number of fruit per plot or percentage of total yield, increased as transplant cell volume increased. In one trial, plants from 7-cm3 cells produced no early yield, while plants from 100-cm3 cells produced 40% of the total yield in the first three harvests. In three of the four trials, total yield of `Superstar' increased as cell volume increased. Marketable early yield of `Mission' muskmelon, measured as number or weight per plot, increased as cell volume increased in three of four trials. In Florida, total yield of `Mission' also increased as cell volume increased. Size of `Superstar' fruit was not influenced by cell volume. In Florida, size of early `Mission' fruit increased as cell volume increased.
A study was initiated at the Southwest Purdue Ag Center to demonstrate the effect of transplant age and transplanting date on the scheduling of melon harvests. Muskmelon (Cucumis melo cv. Superstar) was seeded into #38 growing trays with Jiffy-mix media. Seeding dates were such that 14 and 21 day old seedlings were transplanted April 25, May 9, 17 and 24. The plants were grown on black plastic with trickle irrigation Marketable fruit were harvested starting on June 28 and continuing through August 12. Neither transplant age or date had a significant effect on the number of fruit harvested or on total yield. However, each transplant date showed a distinctive harvest peak beginning June 30 for the April 26 transplant then June 7, 14 and 21 for each successive transplant date.
Small-fruited cherry tomato accession PI 270248 [Lycopersicon esculentum Mill. var. cerasiforme (Dunal) A. Gray] with high fruit sugars was crossed to large-fruited inbred line Fla.7833-1-1-1 (7833) (L. esculentum) that had normal (low) fruit sugars. The F1 was crossed to PI 270248 and 7833 to obtain BCP1 and BCP2, respectively, and self-pollinated to obtain F2 seed. The resulting population was used to study the inheritance of high sugars from PI 270248. Continuous sugar level frequency distributions of BCP1, BCP2, and F2 suggest that the trait is under polygenic control. Additive variation was significant, but dominance variation was not. There was a heterozygote × heterozygote type of epistasis present that likely caused the F1 sugar level to skew nearly to the level of the high sugar parent. The F2 mean sugar level was lower than the midparent level. Broad-sense heritability was 0.86. There was a significant line × season (fall, spring) interaction where lines with higher sugars were affected more by seasons than lines with lower sugars. Sugar level, in general, was higher in spring. Higher solar radiation in spring than in fall may explain the sugar level difference between the seasons.