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- Author or Editor: J. J. Murray x
Limitations in interpretation of data from 1 dimensional chromatograms is illustrated using growth substances extracted from developing seeds of sour cherry (Prunus cerasus L. cv. Montmorency).
Acidic ethyl ether-soluble growth substances extracted from sour cherry (Prunus cerasus L. cv. Montmorency) seeds were subjected to repeated paper chromatography. A growth promoting substance was isolated, active in both the Avena first internode and Avena curvature bioassays, with chromatographic and chromogenic properties similar to those of indole-3-acetic acid (IAA). This tentative identification was strengthened by gas-liquid co-chromatography of the trifluoroacetyl derivatives of authentic IAA and the endogenous growth promoter. Conclusive confirmation that the growth promoting substance is IAA was provided by combined gas chromatography-mass spectrometry.
Endogenous acidic and neutral growth-promoting substances were extracted from sour cherry (Prunus cerasus L. cv. Montmorency) seed and pericarp tissues, separated by ascending paper chromatography and detected by the Avena first internode bioassay. Although correlations were established between the levels of seed auxin and concomitant development of the nucellus and integuments and the development of the endosperm and embryo, no correlation was found between the levels of seed and pericarp auxin or between the level of pericarp auxin and concomitant fruit development.
Ethanolic extracts of sour cherry (Prunus cerasus L. cv. Montmorency) fruit were partitioned into butanol and water-soluble fractions. Following paper chromatography, each fraction was tested for cytokinin activity by the radish cotyledon and soybean callus bioassays. Activity in both fractions increased between 14 and 21 days after anthesis, and remained high at 28 days, although cell division in the pericarp had ceased. One growth promotor in the butanol fraction resembled zeatin in its chromatographic mobility on both paper and Sephadex LH-20, and was identified as zeatin by gas chromatography-mass spectrometry of its trimethylated derivative. A water-soluble growth promoter, which exhibited activity in only the radish cotyledon bioassay, was unaffected either by acid or by alkaline phosphatase hydrolysis.
`Bartlett' pears (Pyrus communis L.) were harvested and ripened with and without ethylene in standard field bins at a commercial cannery. Mean firmness and firmness uniformity within a bin was evaluated for ethylene- and nonethylene-treated fruit. Uniformity of firmness among pears within a bin increased as ripening progressed. Applying 100 ppm (10 Pa) of ethylene gas during the first 24 hours of commercial ripening accelerated ripening of `Bartlett' pears held in standard field bins. Improved firmness uniformity would therefore be expected in ethylene-treated fruit commercially ripened to a lower firmness than untreated fruit otherwise ripened and processed at a higher firmness—the improved firmness uniformity was due to the lower firmness and not a specific effect of ethylene on ripening uniformity. When fruit were cold-stored for 20 days at 32 °F (0 °C) before ripening, the mean firmness and firmness uniformity of fruit exposed to ethylene during initial ripening was no different than nonethylene-treated fruit. Results from this study also indicate that fluctuations in ripening room air temperature, under some conditions, might increase firmness variability between fruit within a standard field bin.
The adhesives gum arabic, Methocel A-15, Pelgel, Solka Floe, and 2 experimental materials were evaluated for their effect on germination and early seedling growth of ‘Kentucky 31’ tall fescue (Festuca arundinacea Schreb.), and ‘Adelphi’ Kentucky bluegrass (Poa pratensis L.) and for their ability to retain a limestone seed coating. The adhesives did not adversely affect seed germination, turf quality, and early growth of seedlings of either species. Seedling growth of ‘Adelphi’, however, was enhanced by Methocel A-15 when compared to the control. Adhesive effectiveness for the retention of a limestone seed coating was in the order: Methocel A-15 > Pelgel > Solka Floe > AP-1 = AP-2.
Various rates of ancymidol granular incorporated, granular broadcast, soil drench, and foliar spray treatments were tested on 7 breeding plant species. Generally, treatment of media affected plant height more than foliar sprays. Media treatments reduced height linearly, with increasing rates reducing plant height. Effects were similar for Salvia splendens F. Sellow ex Roem. & Schultz and Pelargonium × hortorum L.H. Bailey plants. Height of Targetes erecta L. plants was controlled most effectively by 311 to 622 mg a.i. m−3 drenches or granular incorporated. Begonia semperflorens - cultorum Hort., and Antirrhinum majus L. plant height was best controlled with granular incorporated ancymidol at rates of 155 to 622 mg a.i. and 311 to 1243 mg a.i. m−3, respectively. Germination of Tagetes and Pelargonium seed was unaffected by granular incorporated ancymidol at 78 to 311 mg a.i. m−3. Chemical names used: a-cyclopropyl-α-(4-methoxyphenyl)-5-pyrimidinemethanol (ancymidol).
Historically, calendar date has been used to determine when cuttings are collected for rooting. However, year-to-year variations in climate limits the usefulness of using calendar date. More recently, rooting of stem cuttings has been associated with chilling accumulation. In the winter, daily temperatures in northern New Mexico can fluctuate from below freezing to well above freezing. Eight chilling accumulation models and calendar date were tested to determine the best predictor of rooting of white fir. The chilling accumulation models ranged from those based on number of hours at low temperatures to weighted models that calculated chilling unit accumulation and loss. In addition, temperature data based on 3-, 6-, 12-, and 24-hour averages were used. Most of the models were better than calendar date in predicting rooting. The best model was a weighted model that accumulated chilling from -5 to 10C with loss of chilling >15C and less than -10C. Other models that performed well included models that accumulated chilling from 0 to 7.2C, 0 to 15C, or -3.5 to 10C. On the average, the data based on 12-hour means was the best for modeling chilling accumulation to predict rooting.
Seedling emergence from primed and nonprimed sugar beet seed (Beta vulgaris L.) was studied for 3 years under field conditions near Kimberly, Idaho, and compared with germination or emergence under controlled laboratory conditions. Maximum seedling emergence did not vary with seed treatment in spite of low field soil temperatures. Time to 50% of maximum emergence was significantly less for seed primed with polyethylene glycol 8000 than for nonprimed seed in only 1 of 3 years. Seed soaked in 30C water for 24 h performed similarly to nontreated seed in the field, but their maximum emergence was significantly improved compared with primed seed in one of two laboratory experiments. Time to 50% of maximum germination was improved by priming with or without a warm water soak in one of the two laboratory experiments.
`Bing' sweet cherry (Prunus avium L.) trees were treated with hydrogen cyanamide (CH2N2) or calcium ammonium nitrate (CaNH4NO3) during dormancy, or gibberellic acid (GA3) 26 days before harvest during three consecutive years. Fruit were evaluated at harvest for sensory taste quality using twenty trained panelists sampling for firmness, sweetness, tartness, and cherry flavor. Nondestructive instrumental firmness preceded destructive sensory firmness on the same untreated and GA3-treated cherries in one year when used as a supplementary evaluation. Sensory firmness was consistently higher in GA3 fruit and to a lesser extent in CH2N2 fruit than in CaNH4NO3 and untreated fruit. Instrumental firmness of GA3 fruit did not increase significantly compared with untreated fruit yet instrumental firmness of each treatment correlated relatively well with perceived sensory firmness. Sensory sweetness and cherry flavor scored very similarly, yet both attributes simultaneously varied between treatments across the years. Perceived sensory tartness of treated fruit was variable among years; yet, on average, was rated among treated and untreated fruit as similar. Under the assumption that elevated sensory firmness, sweetness, and cherry flavor intensity reflects improved sweet cherry quality, GA3 fruit were rated of higher quality than untreated fruit given their increased firmness and similar or occasionally elevated sweetness and cherry flavor intensity. CH2N2 fruit maintained quality similar to that of untreated fruit, despite often having marginally higher firmness, due to similar or reduced ratings for sweetness and cherry flavor intensity. Notwithstanding similar firmness between CaNH4NO3 and untreated cherries, sensory quality of CaNH4NO3-treated cherries was reduced due to their often-diminished levels of perceived sweetness and cherry flavor.