East Africa Vegetable IPM IL Annual Report
October 1, 2016 – September 30, 2017
Background
The East Africa Vegetable Crop IPM Innovation Lab works in Feed-the-Future areas of Ethiopia, Kenya, and Tanzania to build the capacity of local institutions to implement effective IPM research and locally-adapted technology transfer programs to reduce losses attributed to pests while reducing use of synthetic pesticides. Our intent is to improve crop productivity and enhance incomes for growers while reducing environmental impacts of crop production in the region.
This report is for activities for the Fiscal Year 2017. Progress reports are arranged by country.
Location – TANZANIA
Collaborators
At Sokonie University of Agriculture (SUA), Morogoro, Tanzania: Drs. Amon P. Maerere, Delphina P. Mamiro, Maulid W. Mwatawala, Hellen Kanyagha, R.O. Majubwa, Gratian M. Rwegasira, Kallunde P. Sibuga, Hosea D. Mtui, Elias Mgembe.
At Mikocheni Agricultural Research Institute (MARI), Dar es Salaam, Tanzani: Dr. Peter Sseruwagi, Dr. Joseph Ndunguru, Malidhia Njelekela
Activities at Sokonie University of Agriculture
Vegetable Production Baseline and Impact Assessment Surveys
Baseline survey to identify priority pests, pest management practices, knowledge of IPM was conducted in the two project target regions of Morogoro and Iringa, involving 5 districts and three villages in each district. The 15 villages surveyed had a total of 12,958 households and a population of 53,636 (27,903 female, 25,733 male).
Most vegetable growers in the new study areas are individuals with at least a primary school level of education. Besides seeds, the most important vegetable production inputs used by farmers are synthetic fertilizers and pesticides. Tomato growers reported a wide range of insect pests compared to the growers of other vegetable crops. The most important insect pest of tomato was the tomato leaf miner (Tuta absoluta) followed by aphids (Aphis gossypii) and Red spider mites (Tetranicus urticae), With respect to diseases, blights (early and late blights) were the most important in all the four vegetable crops. Farmers’ knowledge on diseases was generally more limited compared to insect pests and weeds. Chemical pest management was the commonest practice across all crops. Overall, most of these vegetable growers, with whom we have not worked previously, had little knowledge of IPM practices. Hence the frequency of spray using synthetic pesticides was very high. This suggests that pest management is causing an increase in production costs and that produce are being harvested and sold with high pesticide residue levels.
The vegetable growers sold their harvests mainly at farm gate. Some tomato, cabbage, and onion growers sold at a local market and at a road side. The important buyers at a farm gate and road side were middlemen coming from different regions.
For the areas of Tanzania where OSU and the IPM-IL has not previously worked, the baseline survey included 404 farmers, 23% female and 77% male. Farms had an average of 4.3 acres, and tomatoes, onion, and cabbage were their main vegetable crops. Only about 12% of farmers had heard of IPM.
On-station experiment on tomato and cucumber grafting for management of bacterial, fungal and nematode root diseases.
Seeds of solanaceae rootstocks included “Shelter RZ F1”, “Rampart RZ F1″”MT 56” and Soda apple (Solanum incanum). The first two varieties are known to have resistance to bacterial and fusarium wilts. Nematodes were procured from Rijk Zwaan Seed Company in Arusha. The other rootstock seeds were obtained from the existing stocks at SUA. Tomato variety “Nowara” was used as a source of scion.
Preliminary observations showed that for the rootstocks and scion varieties used, seedlings should be of the same age; i.e., the rootstock and scion seeds must be sown at the same time to avoid existence differences in stem diameter between the two during grafting. Luffa gourd (Luffa aegyptica), Calabash gourds (Cucumis ficifolius, C. metuliferus and Legenaria vulgaris) were collected locally for use as rootstocks for Cucumber. Data collection is ongoing.
On-station and on-farm participatory research evaluation of onion varieties for resistance to white grub, thrips, and the purple blotch disease.
A preliminary survey was conducted in Morogoro, Iringa, and Arusha regions to gather information on available onion varieties marketed by Vegetable Seeds Suppliers. Major seed companies contacted were Kibo Seeds, East West Seeds, Africasia, Seminis, EA Seeds and Balton (T) Limited. A total of 6 varieties were found to be currently supplied on the market by the seed companies. The varieties included Russet, Tajirika, Red Creole, Meru Super, Red Bombay and Jambar. Seeds of these varieties were procured directly from the suppliers. A 7th variety, Lumuma Super was found to be locally produced by farmers under the Quality Declared Seeds (QDS) program. Seeds for the variety was procured from Lumuma village in Kilosa district Morogoro region. The experiment is ongoing. The same plots were used during the training under Objective 2 Activity 1. Preliminary observations suggest that the locally produced varieties are out-performing the hybrids in terms of resistance to thrips.
There is a narrow range of commercial varieties in Tanzania. Most varieties are distributed to farmers without prior multi-locational trials to ascertain their ecological adaptability and resistance to major pests. Early results are highlighting differences in the variety resistance to pests, which are expected to influence potential yields under different farmers and on-station based growth environments. Results will enable selection and recommendation to farmers in the respective locations the most suitable variety for production.
Laboratory experiment: to identify the beneficial microorganisms present in bio-slurry (cattle waste after bio-gas production) for use in vegetable pests management.
The number of microorganisms which grew from the cultures were identified as follows:
- Bacterial colonies which contained Bacillus spp., Bacillus subtillis, Corynebacterium spp., Pseudomonas spp. and Streptococcus spp.
- Fungal growths contained Aspergillus spp., Penicillium spp., Cladosporium spp., Rhizopus spp. and Absidia spp.
The bio-slurry contains beneficial microorganisms such as B. subtilis which has the ability to reduce soil-borne diseases.
(ii) Field experiment to determine the effect of bio-pesticides (bio-slurry, neem cake, marigold and microbes (Trichoderma spp.)) on nematode management in tomato and cucumber
Root knot nematode infestation was significantly affected by the bio pesticides used. There was highly significant (p <0.0001) effect of the treatments on the nematodes infective stage (J2/10g of roots) and Root galling index for both cucumber and tomato.
The findings indicated that neem cake and Trichoderma had significant effects on reduction of the infective nematode stage (J2/10 g) of tomato. Marigold effect was similar (p ≤ 0.05) to the control on reduction of infective nematodes. However, marigold and neem cake significantly reduced root galling compared to the control. The findings revealed that bio-slurry significantly increased both J2/10g of roots and root galling index. Neem cake had significant effect on reducing J2/10g of root and galling index in cucumber. Although Trichoderma had a significant effect in reducing root galling of cucumber, it had no significant effect (p ≤ 0.05) on reducing nematode infestation.
Neem cake was the most effective bio-pesticide for control of nematodes in tomato and cucumber. The Season II experiment (ongoing) will provide more insights on the effectiveness of the tested treatments.
On-station and on-farm evaluation of cabbage pests and their management of the diamond back moth.
Diamond back moth (Plutella xylostella) and cabbage webworm (Hellula undalis) were rated as the most important pests of cabbage in Morogoro, regardless of the fertilizer regimes. Grasshoppers and aphids were second in importance, particularly under high N fertilizer application rates. Diseases were not observed in to be important constraint to cabbage production at the site during the season.
Diamond back moth and cabbage webworm were the main insect pests recorded in cabbage followed by Aphids spp. Pest pressure was generally higher in the farmer practice, with high nitrogen fertility. IPM approaches will have to take into consideration the fertilization practices of the crop.
Laboratory Experiment to evaluate efficacy of crude plant extracts for the management of the tomato leaf miner.
Plant extracts caused significantly different mortality rates to egg and larvae of T. absoluta after 5 days of treatment in comparison to the control. Commiphora was the only extract that showed potential to be used as a control agent against eggs, with 0% hatchability recorded. Synadenium resulted in the lowest T. absoluta egg mortality, as hatchability was 96.6%. Commiphora extracts showed the highest effects on T. absoluta second instar larvae while Synadenium extracts exhibited the least effect. Commiphora resulted in the highest second instar larval mortality of 100%.
Results suggest some potential for Commiphora extract to be incorporated into integrated pest management strategies for the control of T. absoluta. We are conducting further studies with refined extract to determine if can be developed into a practical product for managing this insect.
Suppressing populations of tomato leaf miner (Tuta absoluta) in the agro-ecological zones of Morogoro.
- absoluta moth trapped varied significantly between the locations (P< 0.001) and (P< 0.016) for the 1st and 2nd growing season respectively. Population between weeks after transplanting for the 1st growing season was not statistically significant (P> 0.07), compared to that of the 2nd growing season which was statistically significant (P< 0.028). The 2nd growing season had the lowest moth population but showed more significant difference to that of the 1st growing season.
The population of the moth was present throughout the two growing seasons and the three locations. Trapped Tomato leafminer (Tuta absoluta) (Meyrick) populations occurring in Langali (1133 m above sea level) and Nyandira (1584 m) was higher due to favorable climatic conditions, favoring the moth spread and the year-round presence of numerous vegetables that act as suitable alternative hosts for the moth. The alternative hosts facilitated completion of T. absoluta life cycle in the absence of tomato plants.
Title of activity: Management of tomato leaf miner (Tuta absoluta) (Meyrick) (Lepidoptera: Gelechidae) in Morogoro, Tanzania.
Host plants collected for this study were crops readily available in close proximity to the tomato cultivation sites. The number of T. absoluta moths emerged from the collected host samples varied significantly between the host plants (P<0.001) and with a LSD of 9.5. During the survey tomato was observed to be the most preferred host plant of T. absoluta in the two locations. No significant difference was observed between the number of emerged moths in Amaranthus and African eggplant, compared to tomato and eggplant which had had significantly different numbers of emerged moths.
There was in the 1st growing season a significant difference (P <0.049) between the applied treatments. Wiltigo had lower mean population compared to the other control measures. For the 2nd growing season there was no significant difference (P >0.3) between the applied treatments in Dakawa and Morogoro Municipality.
In order to conduct and implement a control strategy for T. absoluta, factors such as alternative hosts should be considered. This is because the moth has a wide range of plants that can facilitate the completion of its life cycle.
On-station and on-farm evaluation of fertilizer rates on insect pests and diseases of water melon.
The treatments had no significant impacts on pest occurrences. However, distribution of individual pest values showed requirements for management of these pests. The distribution of disease data (Phythopthora and downy mildew) show reduced infection rates (30% >) on a majority of experimental units across the treatments.
Activities at Mikocheni Agricultural Research Institute
Biological and socio baseline surveys on vegetable viruses and vectors in Tanzania.
Results indicate that disease and insect pests (62%) were the main constrains in vegetable production. The farmers produced their own nurseries and seedlings, irrigation and manure application (29%). About 75% of the farmers recognized diseases by symptom description, but were unable to tell what the causal pathogens were. Additionally, majority of farmers (88%) complained about serious damage due to viral diseases, especially in tomato and peppers. About 67% of the farmers used own knowledge to manage pests and diseases. Furthermore, chemical pesticides were used the most (13%) compared to phyto-sanitation methods. About 54% of the claimed to use protective gear, although this was not evident during the field visits, probably due to visiting outside the spraying periods. There was poor disposal of chemical containers (38%), and most farmers (54%) lacked knowledge of the importance of proper disposal of the chemical containers, risking contamination of the environment and water sources for human consumption.
Field assessment of vegetable viruses and vectors in Tanzania.
The surveys were conducted three major vegetable producing regions including: Morogoro, Iringa and Lake Victoria (Bukoba and Mwanza). Viral disease incidence ranged from 20% to 93.7% on the vegetable crops assessed in the smallholder farmers’ fields. The viral diseases were highest on okra, green pepper and tomato with 64.4%, 86.4% and 93.7% incidence (see figure below).
Plant virus samples were subjected to PCR and rolling circle amplification (RCA) to detect and sequence the DNA viruses. Sequences were obtained and are currently awaiting analysis at MARI, Tanzania. In addition to morphological keys, mitochondrial cytochrome oxidase I (mtCOI) DNA will be used to study the identity and diversity of the insect vectors.
Evaluation of IPM packages and agronomic practices for management of vegetable viruses and vectors.
Healthy seedlings were produced with an upcoming commercial vegetable seedling producer, Mr. Joseph Mbuji. The project guided Mr. Mbuji on setting new insect proof screenhouses in Kerege, Bagamoyo near the IPM trials for close monitoring of the quality and health of the seedlings.
Mr. Joseph Mbuji is a commercial vegetable seedling farmer with a good knowledge of seedling and vegetable production. He was a participant in the ‘Seedling Health Management Workshop’, conducted at SUA, February 2017. He uses an insect-proof screen house that provides 50% shade net to reduce the effect of sunshine and heat. Seedlings were produced in peat moss and plastic seedling trays from Balton Tanzania Ltd, a private company that deals in horticultural products. He used raised wooden platforms to keep the seedlings away from soil contamination and for easy management. Two tomato varieties were planted: Kipato and Victory, which are popular varieties selected with guidance of farmers. For brassicas (Chinese Cabbage), they selected Michihili and Fahari F1. Other GAP included: weeding, spacing, staking and pruning. All plots were managed uniformly with GAP practices: proper spacing, staking and timely weeding and pruning.
Field data will be analyzed by using ANOVA, a process that is ongoing. Virus identification and characterization is being conducted in the lab using leaf samples collected for confirmation of virus species. Laboratory sequence data will be analyzed using Geneous software.
Location- KENYA
Collaborators
Drs. Jesca Mbaka, Beth Ndungu, Charity Gathambiri, Caeser Kambo, Sylvia Kuria, Samson N. Kihara, S.J.N. Muriuki, Kenya Agricultural and Livestock Research Organization, KALRO
George A. Odingo, Mulinge Mukumbu, Stephen New, KAVES
Henry Wainwright, Patrick Mathenge, Real IPM
Danny Coyne, Luara Cortada-Gonzalez, IITA-Nairobi
Participants:
Dr. Geofrey Gathungu, Chuka University
Prof. Sheila Okoth, University of Nairobi
Rosemary Muthomi, Meru Greens Horticulture
David Mokaya, Agriculture Department, Tharaka Nithi
Hellen Kanyua, Agriculture Department, Tharaka Nithi
Anne Weveti, Agriculture Department, Tharaka Nithi
Samuel Rugendo, Agriculture, Livestock and Fisheries Department, Tharaka Nithi,
Jasper Njue, Agriculture Department Tharaka Nithi
Jotham Burundi, Agriculture Department, Tharaka Nithi
Activities at Kenya Agricultural and Livestock Research Organization (KALRO)
Participatory Identification of Pest Constraints in Selected Vegetable Crops and Farmer Management Practices in Tharaka-Nithi County, Kenya
The results revealed that a typical household had an average of six members and the mean age of the respondents was 57 years for the head of the household and 43 for the spouse. About 82% of the household heads had attained primary and secondary school education, 10% tertiary and 7% had no formal education. For the spouses 71% had primary and secondary school education, 8% had tertiary education and 22% had no formal education.
The sources of household income included crops, livestock, business and salary among others. A majority (73%) of the households were distributed in the first three income quartiles with an annual earning of below KES 30,000 to KES 120,000. Only about 27% of the households had an annual income of more than KES 120,000 (about $1,160).
The average farm sizes were 2.5 acres with an average acreage of less than half an acre for French bean and cabbage, and about half an acre for tomato. Important tomato varieties grown by the farmers were “Onyx” produced by 40% of the respondents, “Kilele” (24%) and “Riogrande” (18%). For cabbage, farmers mainly grew “Sugar loaf” variety (40%), while for French bean the most important variety was “Sagana” grown by about half of the producers.
Various pests and diseases of economic importance were identified under each target crops.
The most serious diseases in tomatoes were bacterial wilt, which was mentioned by 71% of the respondents, followed by leaf blights (52%) and nematodes 30%. The most common tomato pests were white flies according to 70% of the interviewed farmers, leaf miners (64%), spider mites (52%), and Tuta absoluta (36%). Black rot was mentioned as a key cabbage disease by 70% of the respondents while diamond back moth and Aphids were important arthropod pest according to 68% and 60% of the interviewed farmers respectively. Important French bean diseases were rust (57%), angular leaf spot (47%) and anthracnose (33%) while pod borer, thrips, bean fly and mites were identified by most farmers as main arthropod pests by 55%, 51%, 49% and 43% of the respondents, respectively.
A majority of the farmers (86%) used pesticides to manage vegetable pests, with tomato farmers applying pesticides about 17 times per growing season at a cost of about KES 21,000 (~$203) per acre. The French farmers applied pesticides about 12 times per season and spent an average of KES 14,000 while for cabbage, farmers sprayed their crop about eight times spending an average of KES 5000 for one acre every season. Farmers used a range of non-chemical pest control methods including staking in tomatoes (43%), pest resistant varieties, and removal of damaged plants.
Reasons for use of non-pesticides were less exposure to associated health risk, lower cost of non-chemical pest control methods than conventional pesticides, and little contamination to the environment
Farmers were asked whether they had received any training on IPM. About 40% of the farmers had heard of IPM while over 60% had not received any training related to IPM. Main sources of farmer training on IPM were Ministry of Agriculture Livestock and Fisheries (MoALF) and other agriculture based institutions.
This study sought to find out the division of roles on crop protection activities in the study area and this was largely a male domain. More than 60% of the interviewed heads of households applied pesticides on their crops while about 21% of the labor was provided by hired male laborers. The decision making pattern on buying and application of pesticides as well as use of income from vegetable sales between husbands and their wives was also dominated by the husbands
Heads of households were the ones who mainly purchased pesticides (75%), made main decisions on amount of money to be spent on pesticides (72%) and when to apply pesticides (61%). Decisions on how to spend money from the sale of the vegetables was, however, shared by head and their spouses (54%) with only 39% of the household heads claiming to solely decide on how to use money from vegetable sales.
This study recommended the need for researchers to develop crop specific IPM packages for target crops and train farmers on proper pests and disease identification and IPM management strategies and their benefits. The study prioritized tomato bacterial wilt and Tuta absoluta, cabbage black rot, diamond-back moth and French bean for future research in developing, validating and disseminating technologies for their integrated management.
Baseline Socioeconomic Survey of of Nyeri, Tharaka Nithi, Nakuru and Bomet Counties.
For Kenya, data from the baseline survey (403 farmers) conducted in the previous year were cleaned, formatted, and summarized in tables. The data include priority pests, pest management practices, knowledge of IPM, extent of current vegetable IPM adoption, who the adopters are (low or high-income farmers, male or female), and why they adopt or do not. The crops include tomato, cabbage, and French beans for the counties of Nyeri, Tharaka Nithi, Nakuru and Bomet. The data were analyzed in an MS thesis to assess factors affecting adoption of IPM practices and current pesticide use.
The Kenya Baseline survey included 206 male and 197 female respondents, with a mean of 3.3 acres of land (.33 acres of tomato, .53 of cabbage, .51 of beans, 1.11 of chili peppers, and .47 of onions). Most (257) farmers sold their vegetables to traders (25% of them were consumed at home) and most farmers used irrigation. Fifty percent of tomato farmers feel they have a high severity pest insects and diseases, and that diseases/viruses cause the most damage (especially bacterial wilt and bacterial canker). The two most common non-pesticide means they use to manage those problems are staking the plants and removing damaged plants. The main reason they use a non-pesticide practice is to save costs. They apply pesticides an average of 7.9 times and spend 7.9 days spraying and 5.6 days weeding.
Roughly half of cabbage producers felt that the severity of insects and diseases was low with 45% saying that insects/worms were their major type of pest and 51.6 % saying that diseases were their main pest problem. Black rot was their worst disease. Removing damaged plants was their main non-pesticide practice used to manage insect and disease problems. Cost considerations was the main reason they gave for using non-pesticide practices rather than pesticides. They applied pesticides 4.5 times, spent one day spraying and 10 days weeding.
Similar numbers of French bean producers felt that their insect/worm severity was low (27.7%), medium (31.9), or high (36.2), and 44.7% felt that their disease pressure was medium (a fourth low and a fourth high). Rust and blight were their worst diseases and white flies their worst insect pest. They applied pesticides an average of 7.1 times and spent 13 person days weeding. Removing damages plants was their most utilized non-pesticide pest management practice. Cost compared to pesticides was the reason the most important reason for using a non-pesticide practice.
Analysis of the for Kenya data found that experience in vegetable cultivation, wealth, and being a member of a farm or community organization have a positive impact on IPM adoption and distance to town a negative impact. Male farmers were more likely to adopt resistant varieties, but for some practices, such as staking tomatoes, adoption was reduced by lack of credit or off–farm income. For all three vegetables, greater distance from town and lower insect and disease stress reduced pesticide applications.
On-farm participatory field trials.
The sixty-nine farmer group members participated in the on-farm validation of Trichoderma and a bio-fertilizer for management of bacterial wilt of tomato. Preliminary results showed that Trichoderma reduced wilt incidence by 40%. Azadirachtin (Nimbecidine EC), Bacillus thuringiensis (Halt 5WP), pyrethrum + garlic (Pyegar 35.7 EC) and petroleum spray (DC-Tron) suppressed leaf-miner populations and reduced Tuta absoluta damage in tomatoes. Cabbage variety “Queen F1” and tomato variety “Kilele F1,” resistant to black rot and bacterial wilt, respectively, were introduced to and adopted by farmers. Preliminary results indicate that Trichoderma reduced nematode damage in French beans despite the heavy galling by the nematodes.
The participatory research model is operating effectively in Kenya, perhaps because farmers are willing to organize and are somewhat educated in concerns about pesticides. The goal for next year will be to double this number. We are considering ways to expand that might involve farmer-to-farmer training.
Trial 1: Validation of biopesticides in the management of Diamondback moth (Plutella xyllostella) in cabbage and kale.
Infestation by DBM occurred very lightly and late in the season consequently data collection was carried out only once before the crop was abandoned. Sparse infestation by aphids was also noticed but these were adequately managed by hoverflies and parasitic wasps.
Trial 2: Validation of Trichoderma strains and Plantmate biofertilizer effects in the management of bacterial wilt and root knot nematodes in tomato.
Season one failed due to seed impurity while the second season planting was delayed due to poor seed germination caused by very low temperatures at Nthambo where the nursery was set. The seeds were then sowed at Mbwiru-Mwanjati where it is warmer and now the tomatoes have been transplanted and data collection will start as soon as wilting starts.
Trial 3: Validation of selected biopesticides for management of Tuta absoluta, serpentine leaf miner (Liriomyza trifolii) and other arthropod pests of tomato
Nimbecidine EC (Azadirachtin), Halt 5 WP (Bacillus thuringiensis(kurstaki) and DC-Tron Plus (Refined base Oil 98.8%) had relative low number of leaves showing Tuta damage as compared to the plots treated with Pyegar and the untreated control plots. DC Tron plus had significantly few number of fruits damaged by the Tuta absoluta, followed by Nimbecidine and Halt 5 WP with 0.0, 0.3 and 1.0 damaged fruits per plant respectively as compared to Pyegar 35.7 EC and untreated control plots with each having 5.0 damaged fruits per plant.
Trial 4: Validation of Trichoderma and Bacillus strains for management of black rot and soft rot of cabbage.
There was no incidence of black rot in any of the treatments. The cabbage variety Queen F1 was resistant to bacterial wilt. However, at the end of the season, there was 50 % infection by soft rot. The trial will be repeated with focus on soft rot and treatments will be applied as soil drench at transplanting.
Trial 5: Validation of three biopesticides for management of foliar diseases and nematodes in French beans.
Bionematone treated plots had the lowest root galling index of 2 compared to the control with 7. Real Trichoderma treatment gave the highest percentage of dry matter, 50%, while the rest of the treatments had almost equal amounts ranging from 30% to 34%. Plots treated with Real Trichoderma produced the highest pod yield of over 46 kg, followed by Bionematone which had 37 kg, Nimbecidine with 30 kg, while control had lowest, 21kg. Pod yield and % biomass (dry matter) performance followed the same pattern. Although Real Trichoderma treatments had more galling than Bionematon, they had the highest yield and % biomass.
Location – ETHIOPIA
Collaborators at Hawassa University:
Dr. Ferdu Azerefegne, Leader, Entomologist, and co-PI
Dr. Yibrah Beyene, Entomologist
Dr. Alemayehu Chala, Plant Pathologist
Vegetable Production Baseline and Impact Assessment Survey
The baseline survey was conducted in January and the data were then cleaned and summarized in tables. The data include priority pests, pest management practices, knowledge of IPM, extent of current vegetable IPM adoption, who the adopters are (low or high-income farmers, male or female), and why they adopt or do not. The crops include tomato and cabbage and the survey was conducted in the Oromiya region.
The Ethiopia baseline survey included 288 male and 11 female respondents, with a mean of 3 acres of land (0.63 acres of tomato and 0.31 of cabbage). Most farmers sold their vegetables to traders with very little home consumption. Seventy percent of tomato farmers feel they have a high severity of insect pests and 54% a high severity of diseases. Leaf miners were their most severe insect pest of tomato. The diseases that cause the most damage were bacterial canker, bacterial wilt and leaf blight. The two most common non-pesticide means they use to manage those problems are removing damaged plants and healthy seeds/seed treatments. The main reasons they use a non-pesticide practice is to save costs and effectiveness. They apply pesticides an average of 17 times and spend 61 days spraying.
Forty-three percent of cabbage producers felt that the severity of insects and diseases was medium or high with 49% saying that diamondback moth was their worst pest and 38% saying it was bacterial soft rot. Removing damaged plants was their main non-pesticide practice used to manage insect and disease problems. Cost considerations was the main reason they gave for using non-pesticide practices rather than pesticides. They applied pesticides 10 times, spent 14 days spraying and 25 days weeding. The data are still being analyzed.
Establishing link with the main actors of Vegetable IPM in the Rift Valley of Ethiopia.
Ethiopian participants established contact with the main government office working on horticulture cops in the central rift valley of Ethiopia and Southern Ethiopia. The main offices collaborating are the three plant Health clinics (Ziway, Hawassa, and Arbaminch); the Irrigation Authority, Batu; and the Adami Tulu Woreda Bureau of Agriculture and Natural Resources.
Vegetable producers are not organized like other partnering countries or like cereal and other farming systems in Ethiopia. Vegetable growers in this area will only give land for such demonstrations if they are paid well. Therefore, we work with progressive growers who can serve as agents of change. Two farms (Ato Kassahun Seifus and Wasihun Abebe) have cooperated. Both farms have irrigation facilities and grow various vegetables including onions, cabbage, pepper, tomato, eggplant and cucumber. They are willing to implement some of the options of pest management, including the use of healthy seedlings, monitoring of pests, and delayed pesticide use based on monitoring. The two farms produced onion with only one and two sprays for thrips. The yield of the plots will be harvested in mid-October in presence of the trainee farmers.
Discussion was held with Mr. Taye Afaw, Head of the plant Health clinic and Mr. Alebel Nigussie, pest management expert, on pest issues and the need for farmer training. Together with the Mr. Abrham Walelign, Team leader crop protection in Admit Tulu Woreda Bureau of Agriculture and Natural resources, 103 small scale seedling producers (12 female 91 male) are selected and will have a training on Seed management (cleaning, seed treatment with synthetic chemical and Clorox solution,), seed bed management (types of seed beds, solarisation, protective covering, fertilization, use of manure etc. ), safe use of pesticides, visit to reduced insecticide use to control onion thrips on onion. The plant Health clinic and the Adami Tulu Woreda Bureau of agriculture give services to over 4000 farmers in the area. In addition the Adami Tulu Woreda Bureau of Irrigation Authority on board and discussion were held with Mr. Jilo Gunta (Irrigation Horticulturist), Mr . Nura Tessa Agronomist) and Mr. Negash Head (crop Protection Expert). They are members and organizers of the training.
Contacts and Discussion was held with Mr. Taye Mamo (former head of the Hawassa Plant health Clinic and currently The southern Region Crop protection Expert) and Mr. Mululam Mersha (Head of The Arbaminch Plant Health Clinic). These two offices cater for more than 5000 vegetable producers, Currently, there is influx of vegetable growers from Meqi-Ziway area to Arbaminch because of some disagreements with locals. The experts in these offices will be part of the team to visit the two sites in Meki and transfer the technologies.
Raising Healthy Pepper Seedlings.
The main problem with peppers produced for green pods and dried chili powders, have been the pepper viruses. In the rift valley of the common and most prevalent one is the Ethiopian Pepper Mottle Virus (EPMV) transmitted by aphids. Use of healthy seedlings will give a head start so as to begin with plants that have reasonable chance to produce some yield, although they may succumb to the virus at later stages. Farmers commonly raise their own seedlings. Intensification and continuous production of vegetables in the Rift Valley aided movement of this viral disease from crop to crop. Small companies that sell seedlings have started; however, farmers still use seedlings from their own farm and small scale producers who charge less. An ongoing survey on health of seedlings by graduate student Kumsa Dida indicated that up to 30% of the peeper seedlings produced by local farmers show viral symptoms at planting.
Production of seedlings under net covering helps to reduce the risk of viral infection to seedlings. Small farmers with this simple technology can produce healthy seedlings for their own use and also can sell to fellow farmers. In a small test at Hawassa, the incidence of the EPMV was low because seedlings were raised in an area far from intensive pepper production and the nursery was protected from the surroundings by a 2-m high plastic wall. Peppers that were produced under the net cover were taller than those in other treatments, including those protected with insecticides. The farmers’ practice of repeated spraying with insecticide to protect pepper seedlings from sucking insects has negative effects on their growth, and leaves of these seedlings show some phytotoxicity.
Farmers spend about $500/ha to raise peppers in addition to the seed cost. A small trial showed that raising seedlings under a protective net covering was found to be as effective as insecticide applications; also growing seedlings far from production areas was found to be equally effective.
An 800-meter square area of onion was established to demonstrate monitoring and reduced insecticide application. Farmers in the area usually spray a minimum of eight times, mainly with Profenofos. The onions were planted in July, in the middle of the rainy season. Discussion was held with the owners (Mr. Kasshun and Mr. Wasihun) on crop protection, and with the field hands (Mr. Shelele Abu, Mr. Fekadu Geteye), on how to monitor thrips and the need spraying different insecticides in rotation. They abandoned the former schedule spraying and the onion was sprayed only two times. Some portion of the field was left without spraying for comparison purposes. The onions will be ready for harvest next week.
A study was conducted on seedlings purchased from small scale nursery producers. The seedlings were sorted in to healthy looking and symptomatic plants, which were discarded. The heathy looking plants were planted and protected from vectors for various durations. Those which were protected longer had better pod yield. Protection with insecticide was only slightly better than those unprotected. The study indicates that introduction of technologies like low tunnels can protect plants from insects that feed and transmit viral diseases. The study is a part of MSc thesis of Kumsa Dida.
Tuta Absoluta management studies.
Tuta absulta has become the major threat on Tomato in Ethiopia. Farmers repeatedly spray the insecticide Coragen on weekly or less duration. It is known that the insect develops resistance if sprayed with an insecticide repeatedly and such reports are already coming for Coragen. Farmers in the Central Rift valley spray insecticides which they get from various sources, one of the sources being the cut flower industry. With the aim of increasing the spectrum of insecticides to be use in rotation as part of Tuta IPM, the efficacy of registered products from various sources. Tomato not protected with any of the test insecticides had high number of fruits damaged by Tuta larvae and the fruit yield was significantly lower. There was no significant variation yield among the insecticide treatments. All the tested insecticides gave better tomato yield and the number of infested fruits were low. A follow up study will start in November with rotation of insecticides.
Activities Coordinated by IITA-Nairobi
Activity Leaders: Danny Coyne, Luara Cortada-Gonzalez
Research in progress:
- Application Regime of Trichoderma spp and Bacillus spp for the control of root knot nematodes and bacterial wilt on tomatoes
- Efficiency of antagonistic soil microbes on vegetable pests and diseases under different agronomic practices
- Formulation, mass production and application of selected bio-insecticides against nematodes and agricultural pests. and of microbial bio-enhancers for at least 3 selected resistant varieties of tomato and pepper
- Field and greenhouse trials at greenhouses, research sites at Hawassa and farmer’s (vegetable growers) at Marako, Koka, Bishoftu, Zeway, Jimma, Wachamo, Hawassa.
Location – USA, KENYA, TANZANIA, ETHIOPIA
Development of a Plant Health Communication Network
The Plant Health Network was designed to serve as an outlet for fast communications between main grant participants during workshop events, through the duration of the grant and beyond. The network uses the phone application WhatsApp because it functions the same way across multiple phone platforms and countries. Furthermore, in East Africa WhatsApp is the main text phone application system and many users are already familiar with this platform. Currently, experts and extension educators from Kenya, Tanzania, and Ethiopia are included in the main group with 64% of participants being female.
The group has been active during workshops and has continued to engage throughout the duration of the project, and it has been a good outlet for the dissemination of information. Example of topics discussed include pest and disease identification, and management recommendations against plant diseases and insects. The Network allows for extension personnel and advanced farmers to send photos of symptoms of diseases, insects, and other disorders to a network of experts via WhatsApp to allow for rapid diagnosis. This approach has been successful, particularly as it provides a way for real-time diagnostics.
The metadata for the network resides with Real IPM and Ohio State University, who will jointly coordinate use of images and linkages among sub-groups that are being initiated in various village farming groups. The maximum number of participants in a group is 256, but members can form or join another group and therefore act as a bridge between groups. Members of the initial core group are taking the lead to form and join sub-groups to provide such linkage. Ideally, these would also provide links to value chain partners in the various countries.
As the participants have become more aware of its capabilities there have been more interactions not only from experts in the US but also from experts in the three countries collaborating in the project. We expect that in the future similar networks will be developed with farmers, where the extension educators connect with the farmers they interact with and establish the link with the main network. Denis Nyamu, from Kenya, an MS student of Entomology at Ohio State University will lead efforts to evaluate the impact of the connections established between the core Plant Health Network group and his farmer group at Mwea, Kenya (200+ farmers).
Two significant contributions of our Network to IPM capacity building in East Africa are:
- The Plant Health Network greatly expands the IPM diagnosis and recommendation capacity of every village farming group that forms a linkage.
- The Network is neutral with respect to gender, time, location, income, and social class. Our metrics so far show that women participate at least as frequently as men. Villages linked to the core network can communicate in any language.
Development of enhanced virus identification capacity.
Activity leaders: Robert L. Gilbertson, Monica Macedo, Maria Rojas, UC-Davis.
The aim of his activity is to introduce extension officers and crop consultants in East Africa to diagnostic methods that can allow them to identify the cause of virus diseases in the field.
One of the methods that was introduced was the immunostrip technology, including a new general immunostrip for potyvirus detection that was brought to the workshop along with immunostrips for Cucumber mosaic virus (CMV), Tobacco mosaic virus and Tomato spotted wilt virus (TSWV).
Samples of the Chinese cabbage and cucurbits were returned to UC Davis and RNA extracted and tested for potyvirus infection by RT-PCR with degenerate primers. It appears that we have identified two new potyvirus species from Tanzania.
These results also suggested that the potyvirus immunostrips were either not able to detect all potyvirus species (like these new species) or that in some cases the immunostrip test result was weak. When using the potyvirus immunostrips it is often necessary to wait longer for results, and that positive samples can be weaker than samples with other immunostrips.
Based on the results of the sequencing of the helper component proteinase (HC-Pro) and cylindrical inclusion (CI) genes of the cucurbit viruses from Tanzania, there may be two new species of potyvirus infecting cucurbits. Inoculation of pumpkin plants (cv. ‘Big Max’) with samples of the putative two viruses results in development of mosaic/mottle, yellowing, and distortion, similar to symptoms observed in the field in Tanzania. Moreover, the symptoms of the putative two different viruses were different: isolate F4P1 induced very strong stunting, leaf distortion, crumpling and mosaic; whereas the other isolate F4P4 induced strong yellowing, mosaic and crumpling. These results are consistent with the presence of two distinct species of potyvirus.
Capacity Building
At the vegetable industry level, we now have farmers trained to produce high quality vegetable transplants that resist/tolerate pests and diseases and require fewer pesticide applications. Some farmers have now specialized in seedling production, a market that will not soon be satisfied. With healthy seedlings and other IPM approaches, farmers in three Kenyan villages are now marketing together French beans and other vegetables that would probably qualify for organic certification. The connection of IPM as a management approach together with business management skills appears to be effective in changing the industry in the three villages. Farmers in Tanzania are moving in this direction, and this is where value chain partners (MnM, TAHA) can help to provide the business training. The marketing situation in Ethiopia is less organized, and there is no associated value chain partner working in vegetable crops. At the individual level, many farmers, extension officers, Ministry of Agriculture personnel, and others have received training in IPM technologies and pest/disease diagnosis. We have evidence that in many cases this is being translated into adoption of new practices in the field, which are expected to reduce pesticide use and result in higher quality vegetable crops. In many cases, the use of IPM has allowed farmers to reduce the number of pesticide applications, with considerable cost savings; the farmer groups in Kenya provide many examples of this. At the institutional level, we have expanded the capacity for IPM research and education in several ways. One is the common experience in participatory on-farm trials combined with training. In other words, it is not just the farmer who learned from these; researchers and their staff have learned how to test and demonstrate IPM technologies. The whatsapp network has helped to build IPM diagnosis capacity by providing regional and international connections to pest information. It has also been a way for experts to demonstrate how to diagnose and respond to pest/disease problems or other plant disorders. The network essentially provides growers and managers with direct access to extension experts. At the research institution level, the project is supporting advanced training for 12 students, who are expected to return to university, research institute, or ministry-level positions with new expertise, and understanding of IPM, and the kinds of personal connections that can help to continue the advancement of IPM at multiple levels of the vegetable crop value chain.
Lessons Learned
Good work is under way in all three countries, and they are focusing in different ways depending on their needs for IPM research and outreach capacity. The most important effort that is underway is the development of relationships among researchers and research groups within and among countries. This is critical for the future capacity of IPM in these countries. The Tanzania group has the most activity in developing new technologies, i.e. novel botanical extracts for tomato leaf-miner, anaerobic disinfestation for soil-borne pathogens, finding new disease-resistant rootstocks, identifying thrips tolerance/resistance in onion varieties. The intention is that successful technologies will be scaled up in the third year of the project. The Kenya group is more focused on outreach to new groups of farmers who have recently joined together for farming and marketing. They are using fairly established IPM technologies, and have been successful in getting farmers to adopt them. The emphasis for year three will be on expansion of this effort, along with continued work on some novel biological products. The Ethiopian group has taken the longest to get started. This is due to several factors: unfamiliarity with management of the funding approach, internal political issues that inhibited communication networks, and the fall armyworm crisis that pulled entomologists away from vegetable IPM efforts. Nevertheless, they have field work underway and three MS students engaged in research, and are planning to host the project’s annual meeting in 2018.