Increased and sustainable production of healthy and nutritious protein crops (218896)

Oil seed rape and turnip rape, field pea and field beans (oil and protein crops) are important for Norwegian food and fodder production. However, due to yield variations and harvesting difficulties, the actual land area cultivated with these crops in Norway is small (2-3% of the total cereal cropping area). Diseases of these crops, shown to cause substantial yield losses, have not been widely studied in Norway previously. To improve integrated disease management strategies that can contribute to increased cultivation of these crops, the current project focused on occurrence of seed borne inoculum, disease development and yield loss under Norwegian field conditions. The economic benefit of these crops in cereal rotations and their nutritious value used in fodder concentrates were investigated. Inoculum of pea leaf and pod spot (Ascochyta complex) were found to be somewhat common on pea seed, whereas chocolate spot and bean leaf and pod spot were rarely detected on bean seed. We found traces of Sclerotinia spp. (causing Sclerotinia stem rot, SSR) mycelium on rape seed. Our results indicate that even low inoculum levels of these diseases on seed might result in severe infection under conducive weather conditions. We tested different PCR methods (both standard PCR and quantitative PCR) with different isolates to develop a reliable testing method for SSR in seed and other plant materials. From these PCR tests we have indications (not yet confirmed) that the fungus is more common on seed of oilseed crops than previously known. Some of the sclerotia collected from Norwegian rapeseed field trials infected with SSR were identified to belong to Sclerotinia subarctica. This is the first report of this pathogen on Norwegian rapeseed. Laboratory and greenhouse studies in pea have shown that Ascochyta seed infections can lead to relatively severe disease on plants. Seed treatment with fludioksonil reduced the disease significantly. The use of healthy seeds is important in integrated plant disease management and especially important in organic production. The infection risk model for SSR is based mostly on the assumptions that precipitation before and during flowering, high plant density and previous cropping of susceptible hosts increase infection risk. Field trials in Norway over the last 6 years showed that precipitation during and before flowering correlated with SSR infection risk. However, the amount of precipitation did not correlate well with the severity of disease. We used trap plants, which are flowering rapeseed plants that were planted in the field and exchanged weekly, before they were incubated and assessed for SSR, to test precipitation as the predictive factor for infection. SSR infection on trap plants did not correlate well with precipitation events, either due to the lack of disease inoculum in the close vicinity, or because humidity in the crop canopy was high enough for infection even when there was not precipitation recorded. Leaves and petals were collected from several fields during flowering of rape and analysed for SSR infection using a quantitative PCR method. Surprisingly, petal infection did not correlate well with SSR field infection, while SSR infection of the lower leaves appeared to be a better indicator for this disease. This indicates that SSR might depend not only on petals, but can also enter the stems through leaf infections. However, greenhouse studies showed that rapeseed could be infected with SSR two weeks before flowering and 1 week after, extending the period of susceptibility by at least 3 weeks. Based on our field and greenhouse studies, we can now improve the SSR risk model. One of our objectives in this study was to improve the effectivity of fungicides to control diseases in oil and protein crops by increasing the water volume and reducing the fungicide dosage. We saw a large variation in yield response after fungicide applications between locations and years. The yield increase after fungicide treatments varied between highly significant and not relevant at all. The result from the project provided knowledge for increased use of integrated pest management strategies in Norway which is expected to contribute to increased cultivation of oilseed and protein crops. The pre crop trials showed a significant yield increase (10%) in wheat due to protein and oilseed crops as precrops, when compared with wheat as previous crop. The increase in yield lead to an economic benefit of approximately 180NOK/daa on average. The project provided increased knowledge in feeding value of field beans. Testing digestibility of different raw products in sheep, showed that field beans had similar values as barley and peas, but the protein content of field beans was significantly higher than of peas and. We did not find major differences in feeding value between healthy and diseased field beans and rapeseeds.

Protein crops provide valuable raw materials for the animal feed industry. Their potential to reduce cereal diseases in crop rotations and increase soil nitrogen content is long known. However, Norwegian production of protein crops is covering only 3% of the cereal cropping area, while foreign imports of high protein raw materials might introduce GMO-crops and Salmonella infected products. Crop choices on commercial fields depend on the economic benefit and stability of crop yield. Crop yields of protein crops in Norway are highly variable, discouraging farmers to invest in protein crops as cash crops or rotational crops. Yield instability is highly correlated with fungal disease pressure in oil seed crops and grain legumes. The main objective of this pro ject is to increase production, yield stability and nutritional value of protein crops by reducing disease pressure in the field. The major diseases of protein crops in Norway are Sclerotinia stem rot of oilseed crops, Ascochyta blight of field peas and C hocolate spot of faba beans. All diseases are seed borne, can survive on plant debris and spread by ascospores, but the significance of each inoculum source under Norwegian conditions is unknown. Effective chemical disease control is directly related to t iming, concentration and sufficient canopy penetration of appropriate fungicides. Disease forecasting models based on pathogen epidemiology and host development can closely align the timing of fungicide applications with the actual infection risk. Economi c benefits of protein crops depend on yield quality and nutritive value in addition to yield quantity. There are no studies available on the effect of protein crop diseases on the nutritive value of animal feed. Our project will address these knowledge ga ps on plant disease epidemiology and on effects of plant diseases on fodder quality, and increase yield stability by improving and implementing disease forecasting models and chemical disease management.