Phytotoxicity and Efficacy of Fascination (6-Benzyl Adenine + Gibberellic Acid) for Enhanced Branching of Dead Nettle (Lamium maculatum Shell Pink ) By Heiner Lieth, Director Linda Dodge Shannon Still Lea Ragaini Ron Lane Jackie Fortunko Project: Interregional Research Project #4 Project Number 23224A - July 20, 2004 Acknowledgements: Ahmet Gulcu Donors/Supporters: CDFA Minor Crops Research Grant, Project 2: Enhancement of the Western Region IR-4 Program to Address California Needs Green Leaf Perennials, Lancaster, PA UC Davis Environmental Horticulture IR4 Center Department of Environmental Horticulture University of California One Shields Ave. Davis, CA 95616 http://envhort.ucdavis.edu/ir4
1. INVESTIGATOR (Name, Address, Phone#): Dr. Heiner Lieth Department of Environmental Horticulture University of California One Shields Ave. Davis, CA 95616 Ph 530-752-7198, FAX 530-752-1819 Email: jhlieth@ucdavis.edu IR-4 ORNAMENTAL DATA REPORTING FORM (Please type or print) LOCATION OF TRIAL: TRIAL TYPE:(check one) FIELD CONTAINER X GREENHOUSE INTERIORSCAPE 2. PESTICIDE: COMMON NAME: 6-Benzyl Adenine + Gibberellic Acid A 4 A 7 FORMULATION: 1.8% + 1.8% (w/w) BATCH NO.: EPA REG. NO. 27135 PRODUCT: Fascination MFG: Valent 3. USE INFORMATION: COMMON NAME SCIENTIFIC NAME PLANT: Dead Nettle Lamium maculatum Shell Pink REASON: enhanced branching of potted crops SOIL TYPE OR TYPE OF POTTING MIX: UC Mix % SAND 35 % SILT % CLAY % OM 65 % ph 6.5 SEEDING DATE EMERGENCE DATE TRANSPLANTING DATE 4/23/04 PLANT OR POT SPACING 6 ROW SPACING 6 POT SIZE 4-inch PLOT SIZE 50 sq. ft. EXPERIMENTAL DESIGN randomized complete block NO.OF REPS 9 (3 blocks) 4. APPLICATION PARAMETERS: TYPE OF APPLICATION: foliar NO. OF APPLICATIONS 2 APPLICATION TYPE manual spray bottle NOZZLE TYPE/SIZE NOZZLE PRESSURE DELIVERY RATE CALIBRATION DATE(S) 5. APPLICATION SUMMARY: APPL.DATE RATES (ppm)* GROWTH STAGE 6/08/04 0, 125 (0.5X), 250 (1X), 500 (2X) 7 weeks post-transplant 6/29/04 0, 125 (0.5X), 250 (1X), 500 (2X) 10 weeks post-transplant *Be sure to provide units 2
IR-4 ORNAMENTAL DATA REPORTING FORM (Please type or print) 6. RAINFALL/IRRIGATION RECORDS: INCLUDE RAINFALL/IRRIGATION INFORMATION (printouts, IR-4 forms, etc.) Plants were watered as needed (at least once daily) with half-strength Hoagland s solution 7. OTHER PESTICIDES, FERTILIZER, LIME AND ADJUVANTS USED: PRODUCT Flagship + Conserve AMOUNT DATE 6/14/04 PRODUCT Orthene + Sanmite AMOUNT DATE 6/23/04 PRODUCT Orthene + Heritage AMOUNT DATE 6/30/04 PRODUCT Talstar F AMOUNT DATE 7/08/04 8. NARRATIVE SUMMARY OF METHODS AND RESULTS: (Use more pages if needed) Materials and Methods Plant Material and Culture. Young plants of Lamium maculatum Shell Pink were received from Yoder Bros. on 4/12/04. These were transplanted to 4-inch pots containing UC Mix on 4/23/04 and maintained in a greenhouse under natural day length for 7 weeks until the experiment began on June 8, 2004. For the experiment, the plants were transferred to a greenhouse under natural day length with day/night temperatures of 77 F/65 F (25 C/18 C) (Figure 1). The plants were watered as needed (at least once daily) during the 6-week experiment with half-strength Hoagland s solution. Applications of pesticides as part of a normal pest management program were made as needed (see No. 7 above). Experimental Procedure. Thirty-six plants were randomly chosen and individually tagged for treatment with 0, 125 ppm (0.5X), 250 ppm (1X) or 500 ppm (2X) Fascination with 9 replicates per treatment. These dosages were prescribed in an IR4 Fascination protocol dated 6/04 (Appendix A). The plants received the first of two foliar spray applications of the designated treatments on June 8, 2004 using manual spray bottles to spray leaves to runoff. The second application was made 21 days later on June 29, 2004. The plants were arranged in a randomized complete block design with 3 blocks and 3 treatment replicates per block. Phytotoxicity and efficacy measurements were taken at day 0 (June 8, 2004), day 21 (June 29, 2004) and day 42 (July 20, 2004). Phytotoxicity evaluations were based on a numerical rating scale of 0 (no injury) to 10 (complete kill) (Table 1). Efficacy measurements consisted of overall plant height (cm) and width (cm) and, as an indicator of branching for Lamium, the number of secondary branches on one branch per pot were counted for 4 random replicates per treatment. Statistical Analysis. The data were analyzed using Proc GLM of the Statistical Analysis System (SAS). The phytotoxicity and change in mean value from the starting plant height, starting plant width, number of secondary branches and number of flowering stems were analyzed for significant differences using t-tests. Results Phytotoxicity. Fascination never showed any phytotoxicity index value greater than 1. Fascination at rates of 125, 250 or 500 ppm showed an increase in phytotoxicity index for Lamium maculatum Shell Pink (Figure 2, Appendix B) at 6 weeks but not at week 3. The 500 ppm treatment had a greater phytotoxicity index than the 125 ppm treatment. Phytotoxicity was generally manifested as slight leaf chlorosis. 3
Efficacy. All Fascination application rates (125, 250 and 500 ppm) increased plant height for Lamium maculatum Shell Pink at 3 and 6 weeks as compared to control (0 ppm) (Figures 3 and 3a, Table 2). The 500 ppm treatment was greater in height than the 125 ppm treatment at week 3 but there was no significant difference between Fascination treatments at week 6. Fascination at all application rates had no effect on Lamium plant width as compared to control (Figure 4, Table 2). Fascination at all application rates had no effect on the number of L. maculatum Shell Pink secondary branches at 3 or 6 weeks (Figure 5, Appendix C). The variability of the number of secondary branches per pot was fairly great and it is suggested that the experiment be re-run with a larger sample size in order to capture the change of standard error that occurred in the samples. There was a significantly greater amount of flowers at 6 weeks in the control treatment than all rates of Fascination application (Figure 6, Appendix C). Discussion Phytotoxicity. While Fascination appeared to raise the phytotoxicity index for Lamium maculatum Shell Pink, the value was very small indicating that the damage was insignificant. Thus we conclude that Fascination has no phytotoxic effect. Efficacy. The application of Fascination at all tested rates increased the height of Lamium maculatum Shell Pink. An application rate of either 250 or 500 ppm had the same effect on plant growth. Fascination appeared to decrease the number of flowers per plant but the decrease may have been due to a delay in flowering rather than a decrease in total flowers. Fascination was effective for increasing plant height but appeared to delay, if not decrease, flowering. Although Figure 5 suggests that branching is affected, the sample size for this particular variable is only 4. The statistical analysis does not allow us to declare the apparent differences as statistically significant. Thus there is a 28% chance that the apparent differences in Figure 5 at 3 weeks are due to random error, rather than Fascination. At 6 weeks this chance is 11%. Thus, now that we know what to look for, we recommend that this experiment be re-run with a larger sample size for branching. It should be noted that Fascination had a dramatic effect on the shape of the potted plant (Figure 3a). Growers should carefully evaluate whether this is desirable for their particular marketing objectives. While it might be problematic for marketing the plant as a ground cover, it could be useful for other purposes. 9. GOOD RESEARCH PRACTICE STATEMENT: I acknowledge that I have read and followed the IR-4 Research protocol and completed this trial following good agricultural practice, or reported any deviations (note any changes from authorized protocol in narrative). SIGNATURE PRINCIPAL INVESTIGATOR DATE 4
Table 1. Numerical plant damage rating scale used for phytotoxicity determinations. Rating Description of plant damage 0 No damage 1 No visible damage but unintended (non-permanent) impact 2 Slight leaf/tissue damage (curling leaves, necrosis, etc.) 3 Marginal chlorosis on some leaves (damage on up to 10% of plant) 4 10% 20% of plant damaged 5 Significant damage to much of plant (30% - 40%) 6 40% 60% of plant damaged 7 Chlorosis or necrosis on most of plant (60% - 70%) 8 Abscised leaves, branch dieback 9 Tissue severely damaged (80% - 100% of plant) 10 Complete kill 85 80 Air Temperature - Greenhouse 184 Temperature (F) 75 70 65 60 55 50 6/5/2004 6/12/2004 6/19/2004 6/26/2004 7/3/2004 7/10/2004 7/17/2004 7/24/2004 Figure 1. Greenhouse temperatures during the experiment to evaluate the effects of Fascination on Lamium maculatum Shell Pink. 5
Phytotoxicity index 10 9 8 7 6 5 4 3 2 1 0 Control 125 ppm (0.5X) 250 ppm (1X) 500 ppm (2X) 0 3 6 Duration of experiment (weeks) Figure 2. Phytotoxicity Index of Lamium maculatum Shell Pink treated with 0, 125, 250 or 500 ppm Fascination. SE bars shown. n=9. See Table 1 for explanation of values. 6
Plant height (cm) 50 45 40 35 30 25 20 15 10 5 0 Control 125 ppm (0.5X) 250 ppm (1X) 500 ppm (2X) 0 3 6 Duration of experiment (weeks) Figure 3. Plant height of Lamium maculatum Shell Pink treated with 0, 125, 250 or 500 ppm Fascination. SE bars shown. n=9. Table 2. Average increase (cm) of height and width for plants in the control and Fascination treatments for Lamium maculatum Shell Pink. The letters indicate significant differences between different treatments (P < 0.05). Means ± SE (n=9). Increase in plant height or width (cm) Height increase Width increase over 3 weeks over 6 weeks over 3 weeks over 6 weeks Control 11.67 ± 1.54 c 7.11 ± 1.08 b 26.89 ± 2.41 a 44.78 ± 2.36 b 125 ppm 21.78 ± 2.09 b 28.67 ± 2.46 a 26.11 ± 2.44 a 53.44 ± 3.17 a 250 ppm 23.78 ± 1.67 ab 29.11 ± 1.76 a 25.22 ± 2.03 a 55.11 ± 1.82 a 500 ppm 37.22 ± 1.59 a 31.78 ± 3.28 a 24.78 ± 2.23 a 50.11 ± 3.42 ab 7
Control 125 ppm 250 ppm 500 ppm Block A Control 125 ppm 250 ppm 500 ppm Block B Control 125 ppm 250 ppm 500 ppm Block C Figure 3a. Representative plants of Lamium maculatum Shell Pink 6 weeks after 2 foliar applications of 0, 125, 250 or 500 ppm Fascination (Week 0 and Week 3). 8
Plant width (cm) 80 70 60 50 40 30 20 10 0 Control 125 ppm (0.5X) 250 ppm (1X) 500 ppm (2X) 0 3 6 Duration of experiment (weeks) Figure 4. Plant width of Lamium maculatum Shell Pink treated with 0, 125, 250 or 500 ppm Fascination. SE bars shown. n=9. 9
Number of secondary branches 30 25 20 15 10 5 0 Control 125 ppm (0.5X) 250 ppm (1X) 500 ppm (2X) 0 3 6 Duration of experiment (weeks) Figure 5. Secondary branching for Lamium maculatum Shell Pink treated with 0, 125, 250 or 500 ppm Fascination. SE bars shown. n=4. 10
Number of flowering branches per pot 20 18 16 14 12 10 8 6 4 2 0 0 ppm 125 ppm 250 ppm 500 ppm Treatment Figure 6. Number of flowering branches per pot at day 42 for Lamium maculatum Shell Pink treated with 0, 125, 250 or 500 ppm Fascination after 6 weeks. SE bars shown. n=9. 11
Appendix A: GROWTH ENHANCEMENT OF ORNAMENTAL PLANTS WITH FOLIAR APPLICATIONS OF 6-BENZYL ADENINE + GIBBERELLIC ACID (FASCINATION) Date: 6/04 Ornamental Protocol Number: 670 General label directions: Refer to product label or Technical Bulletin. Research program: Pest(s)/Plants Plants other than labeled species. Pesticide (common name and trade name): Refer to treatment list shown below. For label, material & if needed, spray surfactant contact: Valent USA, Joe Chamberlin, 770-985-0303, jcham@valent.com Plot size (must be adequate to reflect actual use condition) Replicates Minimum of 4 Treatment Units Controls (untreated controls to be included in all experiments) Application: FASCINATION Dosages - 1/2x 125 ppm or 0.125 pt/5 gal. 1x 250 ppm or 0.25 pt/5 gal. 2x 500 ppm or 0.5 pt/5 gal. Active Ingredient: 6-benzyl adenine + gibberellic acid (FASCINATION). Volume - Minimum of 100 gal/a. Timing - 2 Applications, 21 day spray interval. Record number of branches and length, then increased branching, increased extension and crop safety at 7, 14, 21 (then 2 nd appl.), 28 and 42 DAT. Reports: Method of application: Treatments should be applied according to product label instructions. application equipment consistent with conventional commercial equipment. Report completely on experimental design and method of application. Report plant size height x width before treatment and throughout the experiment. Weather Maintain temperature and precipitation (including irrigation) data. Soil type Identify soil type used in experimental area. Product When submitting data, include EPA registration number of product used. Efficacy Data should include percent control as well as an indication that infestation was light, heavy, etc. Record all application and evaluation dates. Phytotoxicity Record phytotoxicity data at all rates. Use a 0-10 scale. 0 = No Phytotoxicity 10 = complete kill. Please direct questions to: Dr. Robert M. Herrick, IR-4 Project, 681 US Highway #1 South, North Brunswick, NJ Phone: (732) 932-9575, Ext. 629. 12
Appendix B: PHYTOTOXICITY REPORT FORM Lamium Data Phyto Phyto Phyto Rate Rate Rate Fascination Treatment Block Rep 6/8/04 6/29/04 7/20/04 Control A 1 0 1 0 Control A 2 0 1 0 Control A 3 0 0 0 Control B 1 0 1 0 Control B 2 0 0 0 Control B 3 0 0 0 Control C 1 1 0 0 Control C 2 0 0 0 Control C 3 0 0 0 Control Mean 0.11 0.33 0.00 Control Std Dev 0.33 0.50 0.00 125 ppm A 1 1 0 1 125 ppm A 2 1 1 1 125 ppm A 3 0 1 0 125 ppm B 1 0 0 1 125 ppm B 2 0 0 0 125 ppm B 3 0 0 1 125 ppm C 1 0 0 0 125 ppm C 2 0 0 0 125 ppm C 3 0 0 1 125 ppm Mean 0.22 0.22 0.56 125 ppm Std Dev 0.44 0.44 0.53 250 ppm A 1 0 1 0 250 ppm A 2 0 1 0 250 ppm A 3 1 1 1 250 ppm B 1 0 0 1 250 ppm B 2 0 0 1 250 ppm B 3 0 0 1 250 ppm C 1 0 1 1 250 ppm C 2 0 0 1 250 ppm C 3 0 0 0 250 ppm Mean 0.11 0.44 0.67 250 ppm Std Dev 0.33 0.53 0.50 500 ppm A 1 0 1 1 500 ppm A 2 0 1 1 500 ppm A 3 0 1 1 500 ppm B 1 1 0 1 500 ppm B 2 0 0 1 500 ppm B 3 0 0 1 500 ppm C 1 0 0 1 500 ppm C 2 0 0 1 500 ppm C 3 0 0 1 500 ppm Mean 0.11 0.33 1.00 500 ppm Std Dev 0.33 0.50 0.00 NOTE: DEFINE MEASUREMENT OF PHYTOTOXICITY, OR INDEX OF INJURY (0=NO INJURY, 10=COMPLETE KILL) (See Table 1) 13
Appendix C: EFFICACY REPORT FORM Lamium Data Plant Plant Plant Plant Plant Plant Height Height Height Width Width Width Fascination (cm) (cm) (cm) (cm) (cm) (cm) Treatment Block Rep 6/8/2004 6/29/2004 7/20/2004 6/8/2004 6/29/2004 7/20/2004 Control A 1 8 19.5 11.5 14.75 34 42.5 Control A 2 8.5 28.5 19.5 15.25 52.5 55 Control A 3 8.5 23.5 16 13.3 39.75 62.5 Control B 1 9.5 17 15 15.5 41.75 59.5 Control B 2 8.5 25 19.5 9.25 39.5 60.5 Control B 3 8 17 14.5 13.75 37.75 52.75 Control C 1 6.5 15.5 13 12.25 28.25 61.5 Control C 2 9 15.5 11.5 15.25 48 61.25 Control C 3 8.5 19 19 12.5 40.75 67.25 Control Mean 8.33 20.06 15.50 13.53 40.25 58.08 Control Std Dev 0.83 4.60 3.24 2.01 7.10 7.19 125 ppm A 1 9 33 46 14.75 30.25 77 125 ppm A 2 9 33.5 36.5 13.25 32.5 59 125 ppm A 3 8 25.5 24.5 12.75 45.25 77.25 125 ppm B 1 8.5 32 40 13.25 41.75 55 125 ppm B 2 8 26.5 34.5 11.5 32.25 66.5 125 ppm B 3 9.5 37.5 50.5 14.75 51.75 77 125 ppm C 1 9.5 29 35.5 16.5 42.25 76.75 125 ppm C 2 9.5 19 33.5 17.25 44.5 55.5 125 ppm C 3 7.5 39 38.5 14.5 35.75 65.5 125 ppm Mean 8.72 30.56 37.72 14.28 39.58 67.72 125 ppm Std Dev 0.75 6.27 7.48 1.82 7.26 9.61 250 ppm A 1 9.5 32.5 40.5 14 39 70.5 250 ppm A 2 7 29 31 11.75 35.5 74.75 250 ppm A 3 9.5 41 37.5 12.25 32.5 74 250 ppm B 1 8 35 43.5 15.5 38.75 67.75 250 ppm B 2 10 33 42.5 13.75 39.75 61 250 ppm B 3 9 26 36 14 50 66.5 250 ppm C 1 7 30 32 12 32.75 73.5 250 ppm C 2 9 27.5 42 14.25 38.5 60 250 ppm C 3 9.5 38.5 30.5 15.25 48.5 68.5 250 ppm Mean 8.72 32.50 37.28 13.64 39.47 68.50 250 ppm Std Dev 1.12 5.01 5.17 1.36 6.16 5.38 500 ppm A 1 6 30 20.5 11.25 25.5 45 500 ppm A 2 7 40.5 27 13 39.75 73.5 500 ppm A 3 7.5 43 35.5 12.5 29.5 70.5 500 ppm B 1 9.5 37 42 15 44.25 56.5 500 ppm B 2 8 36 48 11.25 35 69.25 500 ppm B 3 10 29 46.5 16.75 43.75 54.5 500 ppm C 1 6.5 31 47.5 11.5 44.25 66.5 500 ppm C 2 7 34.5 46.5 12.5 42.5 74.5 500 ppm C 3 7.5 34 40.5 13.5 35.5 57 500 ppm Mean 7.67 35.00 39.33 13.03 37.78 63.03 500 ppm Std Dev 1.32 4.71 9.84 1.84 6.87 10.15 14
Appendix C: EFFICACY REPORT FORM (continued) Lamium Data # Flowering # Branches # Branches # Branches Branches Fascination Treatment Block Rep 6/8/2004 6/29/2004 7/20/2004 7/20/2004 Control A 1 0 1 6 4 Control A 2 9 Control A 3 10 Control B 1 0 2.0 12.0 29 Control B 2 2 2.0 12.0 30 Control B 3 15 Control C 1 15 Control C 2 2 2.0 2.0 7 Control C 3 15 Control Mean 1.00 1.75 8.00 14.89 Control Std Dev 1.15 0.50 4.90 9.13 125 ppm A 1 1 125 ppm A 2 7 125 ppm A 3 4 3.0 19.0 4 125 ppm B 1 2 6.0 19.0 4 125 ppm B 2 3 125 ppm B 3 17 125 ppm C 1 4 12.0 22.0 16 125 ppm C 2 4 125 ppm C 3 2 2.0 22.0 6 125 ppm Mean 3.00 5.75 20.50 6.89 125 ppm Std Dev 1.15 4.50 1.73 5.71 250 ppm A 1 2 5 250 ppm A 2 2 250 ppm A 3 13.0 14.0 12 250 ppm B 1 5 250 ppm B 2 6 250 ppm B 3 0 10.0 27.0 8 250 ppm C 1 2 3.0 16.0 7 250 ppm C 2 2 10.0 15.0 1 250 ppm C 3 7 250 ppm Mean 1.50 9.00 18.00 5.89 250 ppm Std Dev 1.00 4.24 6.06 3.26 500 ppm A 1 2 2.0 20.0 0 500 ppm A 2 4 6.0 10.0 7 500 ppm A 3 5 500 ppm B 1 7 500 ppm B 2 2 6.0 23.0 1 500 ppm B 3 9 500 ppm C 1 10 500 ppm C 2 7 13.0 38.0 7 500 ppm C 3 1 500 ppm Mean 3.75 6.75 22.75 5.22 500 ppm Std Dev 2.36 4.57 11.59 3.70 15