Search Results (5)

Asparagus decline syndrome (ADS) is a major challenge affecting asparagus production, leading to reduced yield and spear quality. This study evaluated the effectiveness of different control strategies, including biosolarization with Brassica carinata seed pellets, biosolarization with chicken manure pellets, and chemical disinfection with Dazomet. Field trials were conducted over three consecutive years to assess their impact on commercial yield, spear quality, and plant performance. Biosolarization with B. carinata seed pellets increased commercial yield by 17% and the number of spears per plot by 21%, compared to the control. B. carinata seed pellets and Dazomet improved spear weight by 196% and 170%, respectively, and increased diameter by 115% and 95%, respectively, in 2019. In 2021, chicken manure pellets and Dazomet treatments reduced hardness by 11% and °Brix by 5% and 4%, respectively. These findings suggest that biosolarization could be an effective strategy to mitigate ADS effects and enhance asparagus yield and quality. Furthermore, the results highlight the importance of considering biological control methods to manage ADS while preserving beneficial soil microorganisms. This study provides valuable insights for sustainable asparagus production, emphasizing the role of biosolarization as an alternative to chemical disinfection in ADS-affected fields. Full article

Concentrations of specific secondary metabolites can be higher in organically grown crops. This may be linked to organic nitrogen (N) nutrition that provides a gradual supply of N to crops over the growing season. This study examined whether organic N nutrition influenced the concentration of glucosinolates in broccoli crops. Nitrogen release patterns were determined from three synthetic (Rustica, 12% N; calcium nitrate, 15.5% N; urea, 46% N) and two organic fertilizers in an incubation experiment. Broccoli seedlings were then grown in two N dose response pot trials with different N source or application timing treatments to investigate growth and glucosinolate responses. Synthetic fertilizers released 84 to 89% of total N after 28 days, while chicken manure pellets and composted cow manure had only released 52% and 13% of total N, respectively, after 91 days. Broccoli yield and N content were generally higher in synthetic fertilizer treatments. Glucosinolate concentrations were generally higher in the synthetic fertilizer treatments, and only sinigrin and glucoiberin concentrations in the 800 kg ha⁻¹ N application rate of organic fertilizer matched those in the corresponding synthetic fertilizer treatment. Broccoli head weight was reduced when N was applied fortnightly compared to basal and weekly N applications, but glucosinolate concentrations were not significantly different. Overall, there was no evidence that organic (chicken manure) N nutrition, or the rate of N supply to broccoli plants, affect glucosinolate concentrations. Full article

The pig and poultry industries continue to grow across the world and together they provide the majority of meat consumed. The European Union (EU) in particular has the highest global relative meat production by monogastrics (i.e., pig and poultry). The fate of phosphorus (P) in pig and poultry farming was studied, accounting for P content in feed, animals, manure, soil, and runoff. P input from manure, and P offtake in crops receiving manure, were plotted against each other to arrive at “safe” P loading rates, in order to minimize soil P surpluses along the lines of the EU Nitrogen Expert Panel in their work with nitrogen (N). However, it was observed that it is the N/P ratio and the background soil P levels that determine whether a certain manure will end up producing surplus levels of soil P. Critical N/P weight ratios were derived over different crop P offtake rates when applying stored manure to croplands. At spreading rates of 170 and 250 kgN/ha/year and a crop P offtake of 15 or 30 kgP/ha/year, stored pig and chicken manure result in soil P surpluses. An important factor in determining effective N/P ratios is the plant availability of N in stored manure, which runs at around 47%, estimated from previously published results. The minimization of N losses to the atmosphere and to groundwater in housing, storage, and spreading of manure has a major impact on the N/P weight ratio of the manure that ends up on fields. In most cases, half of the ex-animal N content has been lost in stored or degraded manure, with N/P weight ratios running at two and less. Following only the EU Nitrates Directive, which allows for a maximum of 170 kgN/ha/year in NVZs (Nitrate Vulnerable Zones), will often result in soil P surpluses leading to runoff losses to adjacent water bodies. Therefore, for the pig and poultry industries to continue thriving, measures are required to better manage manure, including improved storage and spreading techniques, acidification, separation, struvite extraction and ammonia stripping of pig slurry, and drying and pelleting of poultry litter. This way, excess manure and derived biofertilizers from animal farms can find their way back into the commercial market, instead of ending up as legacy P in watersheds and coastal zones. Full article

Green asparagus (Asparagus officinalis L.) is a widely grown and consumed crop which provides high-level nutritional interest. In recent years, the decline syndrome in asparagus plantations has been rapidly augmenting. This syndrome causes the early death of whole plants, also negatively affecting the new replanting. Decline causes notable economic losses in the sector. The objective of this work was to verify the effect of different treatments against asparagus decline syndrome on the physiological parameters and nutritional quality of the spears. To meet the objective, four different treatments were applied to asparagus plots strongly affected by decline syndrome: (T1) untreated control soil, (T2) biofumigation with Brassica pellets, (T3) biofumigation with chicken manure pellets, and (T4) disinfestation of the soil with Dazomet. The cumulative yield and physiological and quality parameters of green asparagus spears were studied. Thus, malondialdehyde (MDA), photosynthetic pigments, glutathione (GSH), ascorbate (AsA), total phenols, flavonoids, anthocyanin, antioxidant test, mineral nutrients, and the amino acid profile were measured on asparagus spears. The results showed that the Brassica pellets and Dazomet treatments were the most effective against the damage caused by the decline syndrome. However, it would be necessary to monitor the evolution in the following years. Full article

There is increasing concern about the sustainability and environmental impacts of mineral fertilizer use in agriculture. Increased recycling of nutrients via the use of animal and green manures and fertilizers made from domestic organic waste may reduce reliance on mineral fertilizers. However, the relative availability of nutrients (especially nitrogen) is lower in organic compared to mineral fertilizers, which can result in significantly lower yields in nutrient demanding crops such as potato. It is therefore important to gain a better understanding of the factors affecting nutrient use efficiency (yield per unit fertilizer input) from organic fertilizers. Here we show that (a) previous crop management (organic vs. conventional fertilization and crop protection regimes), (b) organic fertilizer type and rate (composted cattle manure vs. composted chicken manure pellets) and (c) watering regimes (optimized and restricted) significantly affected leaf chlorophyll content, potato tuber N-concentration, proteome and yield. Protein inference by gel matching indicated several functional groups significantly affected by previous crop management and organic fertilizer type and rate, including stress/defense response, glycolysis and protein destination and storage. These results indicate genomic pathways controlling crop responses (nutrient use efficiency and yield) according to contrasting types and rates of organic fertilizers that can be linked to the respective encoding genes. Full article