Bionematicides in Brazil: an emerging and challenging market

Management of plant parasitic nematodes in Brazil is a challenge and bionematicides are an important tool in the Integrated Nematode Management in several crops. There are 47 commercial bionematicides with 11 microorganisms as active ingredient available for growers in Brazil; Bacillus spp. are the main biological control agents, but fungi are also important for nematode management. Bionematicides reached 82% of the total market of nematicides in 2019/2020 in Brazil and, in soybean, they represented 90% of the area treated with nematicides. Although, the use of bionematicides is considered an emerging market worldwide, some challenges involve the correct use and formulation of organisms with different modes of action, difficulties in laboratory culturing, and the existence of non-regulated bionematicides, which do not ensure the quality, the purity, and the efficiency in the nematode control under field conditions, leading to lack of control and discredit of this tool. Considering the Brazilian biodiversity richness, a universe of new macroand microorganisms can be explored, as well as the metabolites produced by these organisms as the active ingredient of bionematicides. Expectations of an increase in this market are optimistic and may materialize in light of the increasing demand for biological products in Brazil.

Role of Growth-Promoting Bacteria as Biocontrol Agent Against Root Knot Nematode of Tomato

There are significant losses which have occurred in crops due to the infestation of plant parasitic nematode which are known as hidden enemy due to their presence in rhizosphere and their infection site on the roots. Synthetic nematicidal control is an effective strategy to combat this biotic stress but an inappropriate and deficient application of chemical pesticides have an adverse effect on soil micro-flora and fauna. Due to the environmental and regulatory pressure, use of potential biocontrol agents is the new approach for nematode management by the farming community. For this study, four potential rhizobacteria from different habitats BHU1, BHU2, BHU3 and BHU4 were assessed for their antagonistic activities against Meloidogyne incognita infecting tomato plant. These were characterized on the basis of their morphological and biochemical activities. In vitro screening of bacterial isolates was conducted in a 25-microwell plate by addition of second stage juvenile (J2) of M. incognita with nematode application. Among four bacteria,, three potential antagonistic bacteria were able to kill nematode within 24 hours. Mortality percentage of J2 M. incognita observed in sterile distilled water selected bacterial isolates ranged from 23.33 to 100% in 3h to 24h periods. Moreover, all bacterial isolates except BHU2 isolate were found positive for production of extracellular enzymes like catalase, oxidase, chitinase, amylase and gelatinase which favour effective biopesticide activity of bacteria. Further selected isolates of bacteria associated with tomato have shown a great potential as biocontrol agents against root-knot nematode in tomato during pot experiment. Based on the fact stated above, the current research focused on plant growth promoting rhizobacteria based nematodes biocontrol strategies with direct and indirect mechanism of PGPR for nematode management.

Nematode Management Using Sorghum and Its Relatives

Sorghum and sorghum-sudangrass are often used in crop rotation systems in Florida. They produce a source of forage or silage for animal feed, and many cultivars are effective in reducing population levels of root-knot nematodes, which are key nematode pests in Florida as well as many other parts of the world. This article is intended to guide agricultural professionals in making decisions about producing sorghum and its relatives for nematode management.

Root-Knot Nematode Management in Caladium

Florida leads the commercial production of caladiums, a popular ornamental. In Florida, root-knot, sting, and stubby root nematodes are found in caladium fields. Root-knot nematodes are considered the most important of all pests in caladiums that are grown in sand. This publication will help caladium growers understand what plant-parasitic nematodes are and current nematode management strategies for the caladium industry.

Interaction Effect of Soilless Media and Organic Amendments for Eco-Friendly Root-Knot Nematode Management in Brinjal and Tomato Nursery

Brinjal and tomato are the most important transplanted vegetable crops of the Solanaceae family. The successful cultivation of these crops is vital for meeting the nutritional dietary requirement of India’s population and earning foreign exchange for the country by exporting vegetables to foreign countries. However, there are several abiotic and biotic impediments in the cultivation of these crops. Among biotic impediments , plant-parasitic nematodes have become one of the critical factor adversely affecting the cultivation of these vegetables. In general, Meloidogyne spp. (root-knot nematode) is the most common, widespread and economically damaging plant parasitic nematode species in tomato and brinjal crop. In addition to the damage caused by root – knot nematode, it stimulates the entry of soil-borne pathogens leading to development of the disease complex. The present study was undertaken to study the interaction effect of soil & soilless growing media viz. cocopeat and vermicompost along with organic amendments i.e., Trichoderma, AM fungus, and Cabbage residue incorporated individually as well as in different combinations for eco-friendly root-knot nematode management in brinjal and tomato nursery. The results indicated that treatment C-8 (Cocopeat + Trichoderma + AM fungus + Cabbage residues) recorded the superior germination count, germination percentage, days to 50% germination, root length, shoot length, fresh weight, root weight, shoot weight and root: shoot ratio. It is pertinent to mention that the soilless media, along with various organic amendments, were found to be superior for all the root and shoot attributes as compared to the conventional soil media for growing healthy nursery of tomato and brinjal in root knot nematode infested geographies. Our findings provide an effective and sustainable method of growing healthy plant nursery in nematode infested regions.