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The criminal justice system is served by many experts who provide special assistance to law enforcement professionals during criminal investigations. One of these specialized areas. forensic botany, has traditionally been an activity of the systematic botanist who identifies plant material associated with a suspect or crime scene. From this Information, suspects can be placed at crime scenes and information such as time of death or movement of victims can be determined. Few plant scientists are involved In this emerging field which has the potential to make contributions similar to those made today by forensic anthropology.

Plant scientists with training In systematic botany, plant anatomy, plant growth and development, and statistics and probability can make significant contributions to criminal investigations. The use of plant identification and plant growth analyses In recent criminal Investigations will be described. The role of horticulture in the future of forensic science and the development of new techniques In forensic plant science will also be discussed.

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Abstract

Micropropagated mother plants of strawberry (Fragaria × ananassa Duchesne) often produce more flowers and runners than their runner-propagated counterparts (4, 5), but it is not clear how long this effect lasts. Swartz et al. (5) reported that the increase in runnering of tissue culture plants did not continue after the first flush of runner production in the field, and Marcotrigiano et al. (4) showed that, within the planting year, micropropagation increased runner production in mother plants and their primary runner plants, but not in attached secondary and tertiary runner plants. However, these studies examined runner plants still attached to plants directly out of culture, rather than detached, cold-hardened plants as they are delivered to the grower. In a study where detached runner plants of unknown age were compared, planting stock from micropropagated plants of 4 of 6 cultivars had significantly higher matted row densities ( X ¯ = 63%) than those derived from conventionally propagated stock (2). The goal of this study was to compare the performance of detached primary, secondary, and tertiary runner plants of micropropagated (MP) and standard (ST) mother plants grown under controlled conditions.

Open Access

Twenty-five female clones of Fragaria chiloensis (L.) Duchesene collected from the California and Oregon coasts were surveyed for gas exchange rates under field conditions. Carbon assimilation (A) rates of native clones were 25% to 69% higher than for `Totem' (Fragaria × ananassa Duchesne) on a leaf-area basis (μmol of CO2 per sec/m2) and 7% to 77% higher when expressed on a leaf dry-weight basis (μmol of CO2 per kg dry wt/sec). Higher rates of stomatal conductance (gs) were observed in 16 of 25 F. chiloensis clones than in `Totem', with nine of 25 clones also having higher rates of transpiration (E). All clones had higher rates of residual conductance (gr) and greater water use efficiency (WUE) than the cultivated standard. The gas exchange characteristics of four strawberry cultivars (F. × ananassa) and four F. chiloensis genotypes were compared under standard greenhouse conditions. F. chiloensis genotypes had higher rates of A than cultivars when expressed on per leaf-area and dry-weight bases. Native clones also had higher rates of gs, gr, E, and WUE and greater quantum yield. Differences in chlorophyll content were observed among genotypes, but not between species.

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Several anatomical and physiological parameters were measured in 32 genotypes of fragaia, including the cultivated strawberry (frapria × ananassa) and its progenitor speck F. chiloensis and F. virginiana Measurements were made using potted. runner-propagated, &month-old greenhouse-grown plants growing under long day (14/10) conditions.

Significant differences in CO2 assimilation rates (leaf area and dry weight bases). leaf chlorophyll content, leaf soluble protein content, and leaf anatomy were found between subspecies of F. virginana as well as among species. Recessed stomata and greater water use efficiency were observed in F. virginana ssp glauca as well as in F. chiloensis genotypes. In addition, it appears that leaf anatomy characteristics, as studied using light microscopy, may he useful in corroborating taxonomic decisions based upon gross morphology in Fragaria.

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Fragaria chiloensis (Linnaeus) Is a viable. low maintenance alternative to groundcovers currently available in the ornamental landscape industry. There is considerable genetic variability within this specks for leaf morphology, growth and flowering habits as well as drought tolerance. Clones collected from 11 coastal sites in CA and OR were compared for drought tolerance after two Imposed water stress\recovery cycles. Predawn water potential, gas exchange, chlorophyll (chl) content, fourth derivative spectroscopy, carbon isotope discrimination, and total biomass production were evaluated and significant clonal differences were observed.

Predawn water potentials after the first stress cycle ranged from -35.0 MPa to -6.5 MPa. Clones I05, DNT and G19 had highest predawn water potentials and gas exchange rates after both stress cycles. In the control group, I05 and DNT had higher levels of chl a, chl b, total chl and chl a\b. After the first stress cycle, clones DNT and I05 had the highest chl a\b ratio, however, after the second stress event there were no differences In any chl parameters. Varying adaptive abilities observed may suggest differential use in the landscape.

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Gas exchange measurements were made on healthy and rose bloom infected branches of cranberry on 31 May 1991 during the middle of the sporing period. CO2 assimilation rates of infected branches were reduced 89% on a leaf area basis and 95% on a dry weight basis compared to healthy tissue. Stomatal conductance was 12× higher in infected tissue, while mesophyll conductance was reduced by 92%. Transpiration was 4× higher in diseased tissue reducing water use efficiency by 96%.

Total chlorophyll content of diseased tissue was 81% less than that of healthy tissue but chlorophyll a/b was unchanged. Fourth derivative profiles of chlorophyll action spectra were altered in diseased tissue. Rose bloom leaves were found to lack stomata and have no discernable mesophyll layer.

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Abstract

In the article “The Carbohydrate-Nitrogen Relationship and Flowering/Fruiting: Kraus and Kraybill Revisted” by J. Scott Cameron and Frank G. Dennis, Jr. (HortScience 21:1099–1102, Oct. 1986), on p. 1100, under Experimental methods and designs, the authors note that the sentence reading “Kraus and Kraybill describe 4 experiments (I, III, IV, and V II)...” should read “Kraus and Kraybill describe 4 experiments (II, V, VI, and V II)...” In the article “Gene Transfer System for Potato” by Elias A. Shahin and Robert B. Simpson (HortScience 21:1199–1201, Oct. 1986), an incorrect photograph was printed as Fig. 2C. The correct photograph is printed below.

Open Access

Abstract

In 1918, E.J. Kraus and H.R. Kraybill (22) published “Vegetation and Reproduction with Special Reference to the Tomato.” This bulletin has been described (Table 1) as “classic” (27), and the results hailed as “one of the most significant discoveries in the plant sciences” (29), and “a milestone of progress” (33). Although Kraus and Kraybill discussed the “carbohydrate/nitrogen relationship,” subsequent authors have often quantified this by calculating the mathematical ratio of the 2 components (5, 25, 31). However, Kraus (21), writing in 1925, cautioned against the use of such ratios: “…It is quite unlikely that any mathematical ratio between total quantities of nitrogen and carbohydrates can be established as causative of a limited set of plant functions…. It is remarkable that some of the ratios which have been calculated fit as well as they do.”

Open Access

With the advent of new rotary-head mechanical harvesters, it is now possible to machine-harvest a wider raspberry canopy. In Spring 1996, a trial was established in a grower's field in Lynden, Wash., comparing raspberries trained to two top wires with a 70-cm spread (split trellis) to the conventional single top wire system. Within the split trellis, increases in leaf number per cane (97%), and leaf area per cane (55%) were not reflected in a concomitant increase in total leaf dry weight per cane (35%). Leaf dry weight per fruit weight was 11% less within the split trellis. These data suggest that the canopy is more efficient with this type of trellis. Increases in estimated yield per cane (49%) and projected yield per acre (50%) associated with the split trellis were due to increases in berry number per cane (47%). Fruit number per meter of lateral was 35% greater within the split trellis. Greatest enhancements to yield components were in the upper parts of the canopy where canes were tied over. Since there were no differences in lateral numbers or lateral lengths between the two systems, this increased productivity was due to increased floral expression, enhanced fruit set, increases through Spring bud initiation or any combination thereof. In both trellis systems, the longest laterals occurred on the middle third of the cane and decreased in length progressively towards the tip of the cane. Primocane lengths were shorter (20%) and diameters were smaller (10%) and more uniform in the split trellis system.

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Two sets of field experiments have been set up in Lynden, Wash., to evaluate cold damage to red raspberry `Meeker'. The locations represent newly established crops (fi eld 1) and a field that suffered reoccurring cold damages in recent years (fi eld 2), respectively. Temperature and moisture HOBOs were set up in the check and colddamaged treatments of both of the fields to record the air and soil temperatures and air moisture. The cold-damaged treatments in both fields had significantly higher cane dieback and dead buds. Cold injury significantly reduced berry yield in field 1, but not in field 2, through an steep drop in berry number per cane, mainly due to a significant reduction in lateral number/cane. Cold damage reduced primary lateral number/cane, and increased secondary lateral number/cane in both fields. Secondary laterals were shorter in length and had lower berry number/lateral than the primary ones. It proved that cold damage also delayed initiation and development of secondary laterals, and resulted in more yield loss to the plant. The cold-damaged fruiting cane had lower gas exchange rates, leaf and stomatal conductance, and transpiration rates during fruit development in both fields. It also significantly reduced fluorescence parameters Fo, Fm, Fv, T1/2, and Fq of the cold injury treatment in field 1. On a few cold days this spring, the HOBOs recorded a lower daily low temperature in the cold damaged area than in the check area.

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