Six greenhouse trials of five commercial products marketed as systemic resistance (SR) and plant growth promotion (PGP) inducers were evaluated on tomato (Lycopersicon esculentum Mill.) over a 21-month period. The effect of the inducers on treated plants was measured by monitoring plant growth and disease suppression after inoculation with either plant pathogenic bacteria or nematodes. The commercially available SR/PGP inducers included a bacterial suspension [Companion (Bacillus subtilis GB03)], two plant defense elicitors with nutrients (Keyplex 350DP plus Nutri-Phite, and Rezist with Cab'y), natural plant extracts (Liquid Seaweed Concentrate and Stimplex), and a synthetic growth regulator (Actigard 50W). Growth enhancement was noted in some trials, but the parameter of growth affected often varied with trial. Response to Actigard treatment included significant suppression of bacterial spot [Xanthomonas campestris pv. vesicatoria (Xcv)] in three of the six trials. Companion, Keyplex 350DP plus Nutri-Phite, Rezist and Cab'y, and seaweed products induced only partial disease suppression of bacterial spot in inoculated tomato plants. The alpha-keto acids plus nutrients (Keyplex 350DP plus Nutri-Phite) increased plant growth by 14.3% and improved root condition compared to the untreated control following exposure to nematodes. Results are encouraging, if not consistent, and with a greater understanding of the SR system and the conditions related to product efficacy, such materials may become effective tools for production agriculture.
Charles S. Vavrina, Pamela D. Roberts, Nancy Kokalis-Burelle, and Esa O. Ontermaa
How-Chiun Wu, Mei-Ling Kuo, and Chia-Min Chen
, L. Liu, T. Yang, Y. 2005 Growth promotion of Gerbera plantlets in large vessels by using photoautotrophic micropropagation system with forced ventilation Prop. Ornam. Plants 5 179 185 Xiao, Y. Niu, G. Kozai, T. 2011 Development and application of
Amal de Silva, Keith Patterson, Craig Rothrock, and James Moore
The highbush blueberry cultivar Bluecrop was inoculated with potential plant growth-promoting (PGPR) candidates, including bacterial inoculants Pseudomonas fluorescens (Migula) (strains Pf 5, PRA 25, 105, or 101), Bacillus pumilus (Mayer and Gottheil) (strain T4), Pseudomonas corrugata (Roberts and Scarlett) (strain 114), and fungal isolates Gliocladium virens (Miller et al., Von Arx) (strain Gl.21) and Trichoderma harzianum (Rifai) (strain T 22). Addition of G. virens to pasteurized soil increased leaf area and the number of leaves produced in a 4-month growth period, as well as shoot content of P, Zn and Cu in 1997. Treatment with P. fluorescens Pf 5 increased leaf area and stem diameter. In nonpasteurized soil, plants inoculated with G. virens had greater leaf area, stem diameter, shoot and root dry weight, and more leaves per plant. These results demonstrate the potential of G. virens for increasing growth when used to inoculate blueberry plants in the nursery or at transplanting.
Ertan Yildirim, Huseyin Karlidag, Metin Turan, Atilla Dursun, and Fahrettin Goktepe
decrease negative environmental impacts resulting from inefficient use of chemical fertilizers is inoculation with plant growth promoting rhizobacteria (PGPR). These bacteria exert beneficial effects on plant growth and development and therefore may be used
Kil Sun Yoo, Leonard M. Pike, and B. Greg Cobb
Inner scales excised from dormant bulbs of the short-day `Texas Grano 1015Y' onion (Allium cepa L.) were cultured in vitro and leaf growth was examined. Light promoted leaf growth, but no differences in leaf growth were observed for media pH between 4 and 7. Leaf growth rate in darkness was highest at 24C, reduced at 15C, and greatly reduced at SC. Kinetin promoted leaf growth at 1, 10, and 100 μm. IAA was effective at 1 and 10 μM, but not at 0.1 and 100 μm. GA3 promoted growth at 0.1 μM. No inhibitory effects of ABA on leaf growth could be detected. Chemical names used: 1-H-indole-3-acetic acid (IAA), abscisic acid (ABA), gibberellic acid (GA3), 6-furfurylaminopurine (Kinetin).
Yun Kong, Devdutt Kamath, and Youbin Zheng
light promotion effects on elongation are more obvious under 24- than non-24-h lighting. There were interaction effects between photoperiod and light quality on the elongation growth traits in the present study. For the tested species, B vs. R light
Qinglu Ying, Yun Kong, and Youbin Zheng
of nighttime spectrum treatments on cotyledon area, leaf index, dry matter content, chlorophyll content index (CCI), and specific leaf area (SLA) of arugula and mustard microgreens. Discussion Nighttime B increases elongation growth, with a promotion
Marco A. Velástegui Andrade and Roger A. Hinson
In the United States, the total value of sales of greenhouse and nursery crops increased ≈18% between 2000 and 2006 according to the ERS/USDA (2007) . This growth may have been encouraged by the availability of sales opportunities within the set of
Ainhoa Martínez-Medina, Antonio Roldán, and Jose A. Pascual
Rabeendran, N. Moot, D.J. Jones, E.E. Stewart, A. 2000 Inconsistent growth promotion of cabbage and lettuce from Trichoderma isolates NZ Plant Prot. 53 143 146 Schollenberger, C.J. Simon, R
Jong-Seok Park and Kenji Kurata
) were generated in the nutrient solution; 1 cm = 0.3937 inch. Although the reasons for growth promotion by the microbubbles are still under investigation, one of the possibilities is the larger specific surface area of microbubbles when compared with