Melon wilt (MW) is one of the main diseases affecting the cucurbitaceous crops in the Pacific Central region of Mexico. The use of resistant varieties is the most effective strategy to reduce the damage caused by MW; however, variety performance depends on the fungal race occurring in the field. The use of fungicides, such as benzimidazols and methyl bromide, is a common practice, but there are contamination concerns, and a search is on for alternatives to diminish the negative effects on the agro-ecosystem. The aim was to determine the effect of the application of soil amendments and mulching on the incidence of MW, and on melon yield. Soil amendments incorporated were: rice straw (3 t·ha-1); compost 1, prepared with chicken and bovine manure, and banana and orange wastes (5.7 t·ha-1); compost 2, prepared with bovine and horse manure, coconut wastes and grasses (8 t·ha-1), vermicompost (3 t·ha-1), and a control. All treatments were established using transparent mulching during 21 days. The number of MW propagules in amended soils were similar at 5, 10, and 20 cm deep, but the percentage of diseased plants was higher (4.5%) in the control, which could be caused by the incidence of other fungi propagules, perhaps antagonistic, that contributed in diminishing the MW when compared with the control. The fruit weights and fruit sizes were not different between treatments on small (21–30 sizes), medium (15–18 sizes), and large (9–12 sizes), but total fruit numbers were 1.15-, 1.07-, 0.99-, and 1.09-fold higher when compared with the control. The application of soil amendments affected the antagonistic fungal populations even when it did not affect the cantaloupe yield. We suggest that soil amendments will improve soil fertility and increase melon yields, and studies are currently running.
Mario Orozco-Santos, Javier Farías-Larios, Jaime Molina-Ochoa and José Gerardo López-Aguirre
Shann Tanner, Christina Wells and Gregory Reighard
The effectiveness of soil solarization as an alternative to methyl bromide (MBr) fumigation in replanted peach orchards was investigated at the Musser Fruit Research Farm near Clemson, S.C. A split plot experimental design was used, with soil treatment as the whole-plot factor and rootstock as the sub-plot factor. In Spring 2002, preexisting trees were removed from the study site, and six orchard rows were cultivated and subsoiled. In June, two rows were covered with clear polyethylene sheeting and solarized for the remainder of the summer. In November, two additional rows were treated with MBr (474.3 kg·ha-1), while the two remaining control rows received no soil sterilization treatment. In Jan. 2003, 36 `Redglobe' peach trees budded on Guardian™ or Lovell rootstock were transplanted to the site, and one minirhizotron was installed beneath each tree. Minirhizotron observations were made every 14–21 days from Feb. through Oct. 2003, and stem caliper measurements were taken on four dates during this interval. Trees grew significantly larger in the MBr and solarized rows than in the control rows (P< 0.1; Tukey's hsd), but there were no differences in stem caliper growth between MBr and solarization-treated trees. Reduced aboveground growth in control trees may have been related to greater carbon expenditure belowground: in the absence of soil sterilization, fine root median life spans were reduced by 27–28 days (P< 0.0001; proportional hazards regression) and rates of root production and mortality were significantly higher (P< 0.1; repeated measures ANOVA). Solarization and MBr fumigation appeared to provide similar benefits in reducing root turnover and improving aboveground growth at this site.
Judy A. Thies, Jennifer J. Ariss, Richard L. Hassell, Sharon Buckner and Amnon Levi
: Where do we need more research? 1999 Annual Research Conference on Methyl Bromide. Alternatives and emissions reductions. Paper #55. 3 Jan. 2015. < www.mbao.org/mbrpro99.html > Memmott, F.D. Hassell, R.L. 2010 Watermelon ( Citrullus lanatus ) grafting
Stephen R. King, Angela R. Davis, Wenge Liu and Amnon Levi
; Paplomatas et al., 2002 ; Tsror and Nachmias, 1995 ). Bacterial wilt of tomato caused by Ralstonia solanacearum (Smith) Yabuuchi et al. can be a devastating disease that has few control alternatives. Methyl bromide has not proven effective for control of
Kirk D. Larson and Douglas V. Shaw
Strawberry (Fragaria ×ananassa L.) runner plant production during a 4-year period was compared on nursery soils treated with methyl bromide (MB) and chloropicrin (CP) mixtures (MB:CP) and three alternative soil treatments: CP, mixtures of 1,3-dichloropropene (Telone®) and CP (DP:CP), and no fumigation (NF). The effect of soil treatment on runner plant production for a single nursery propagation cycle was determined in all 4 years. In 2 years, runner production in a final propagation cycle was also determined as a function of soil treatment in previous cycles. A single propagation cycle in NF soil decreased runner production relative to all other treatments. Treatments with CP at rates of 140 to 191 kg·ha–1 generally decreased runner production significantly (P ≤ 0.05) in comparison with treatment with MB:CP; use of CP at rates ≥303 kg·ha–1 resulted in statistically equivalent runner production. In one trial, use of two DP:CP formulations (516 kg·ha–1 of a 7:3 DP:CP mixture, and 448 kg·ha–1 of a 3:7 DP:CP mixture) significantly reduced and did not affect runner production, respectively, relative to the use of MB:CP. Use of MB:CP in the previous propagation cycle also increased runner productivity in comparison with NF. Runner productivity of planting stock produced with 314 kg·ha–1 of CP did not differ statistically from that of stock produced with MB:CP, but productivity of planting stock on soil treated with 157 kg·ha–1 of CP was intermediate between that on NF and MB:CP-treated soil. Planting stock grown on nontreated soil in two previous propagation cycles produced 25% fewer runner plants than did similar stock grown on MB:CP-treated soil. Productivity of planting stock produced with CP at rates of 280 to 314 kg·ha–1 in two previous propagation cycles did not differ statistically from that of stock produced with MB:CP. Results of meta-analyses indicated that fumigation with MB:CP was more effective in increasing runner production than was CP or NF, regardless of the propagation cycle or rate of application. For mixtures of 1,3-dichloropropene and CP, nursery productivity was maximized by using at least 280 kg·ha–1 of CP.
Leonor F.S. Leandro, Lisa M. Ferguson, Frank J. Louws and Gina E. Fernandez
alternative farming systems compared with large-acreage operations. Growers are currently faced with the serious challenge of implementing alternatives to soil fumigation with methyl bromide ( Wilhelm and Paulus, 1980 ; Yuen et al., 1991 ), banned in 2005
James P. Gilreath and Bielinski M. Santos
runner plant nurseries with methyl bromide alternative fumigants HortScience 43 1495 1500 Gilreath, J.P. Santos, B.M. 2004 Manejo de Cyperus rotundus con alternativas al bromuro de metilo en tomate de mesa Manejo Integrado de Plagas y Agroecología 71 54
Judy A. Thies and Amnon Levi
of 15% to 20% for watermelon in Georgia and Florida ( Lynch and Carpenter, 1999 ). The removal of methyl bromide from the U.S. market has raised great interest in developing an alternative approach for managing root-knot nematodes in vegetable crops
Francisco Doñas-Uclés, Diego Pérez-Madrid, Celia Amate-Llobregat, Enrique M. Rodríguez-García and Francisco Camacho-Ferre
.). Global report on validated alternatives to the use of methyl bromide soil fumigation. Plant production and protection paper. FAO, Rome Bosland, P.W. Lindsey, D.L. 1991 A seedling screen for Phytophthora root rot of pepper, Capsicum annuum Plant Dis. 75
Feras Almasri, Husein A. Ajwa, Sanjai J. Parikh and Kassim Al-Khatib
application of alternative fumigants to methyl bromide for strawberry production HortScience 39 1707 1715 Bangarwa, S.K. Norsworthy, J.K. Gbur, E.E. Zhang, J. Habtom, T. 2011 Allyl isothiocyanate: A methyl bromide replacement in polyethylene-mulched bell