Broccoli Residue Research Articles

Influence of Fermented Broccoli Residues on Fattening Performance, Nutrient Utilization, and Meat Properties of Finishing Pigs.

The study determined the impacts of dietary fermented residues' (FBR) inclusion on growth, nutrient utilization, carcass characteristics, and meat properties in fattening pigs. Seventy-two robust pigs were randomly assigned to two experimental groups (Duroc × Landrace × Yorkshire, thirty-six pigs each). Each group was subjected to a 52-day trial, during which they received either a corn-soybean meal-based diet or diet enhanced with a 10% addition of FBR. Consequently, adding 10% FBR caused a significant decrease in the digestive utilization of crude dietary components in fattening pigs (p < 0.05) but showed no significant impact on the growth performance. Additionally, FBR inclusion increased the marbling scores (p < 0.05) and total antioxidant functions (p < 0.05) of muscle tissues, indicating improved meat quality. Gender affected backfat depth, with barrows showing thicker backfat depth. In conclusion, dietary supplementation with 10% FBR in finishing pigs influenced the meat quality by improving the marbling score and antioxidant performance while reducing digestibility without compromising growth performance.

Synthesis of bioethanol from mixed vegetable wastes: Experimental methodology and characterization

AbstractBioethanol has been identified as a renewable product with high potential for application as biofuel. On the other hand, high volumes of agri‐food residues are generated daily. Such residues have potential as raw materials for industrial bioethanol production. There is a significant advance in the synthesis of biofuels from fruit and vegetable residues; however, most of the studies are focused on the conversion of a single type of raw material, limiting the application of the synthesis routes. This work presents a conversion methodology to produce bioethanol from carrot and broccoli residues and from their mixture; the samples of vegetable wastes has been collected in the municipality of Guanajuato, Mexico. Using the 1H NMR technique, the characteristic signals of bioethanol are identified. On the other hand, using the UV–VIS spectrophotometry technique, a maximum of 25.63 mg of total sugar content has been determined for the mixture. Likewise, a maximum bioethanol concentration of 60.6 g/L is obtained. From a refractometry and HPLC study, a conversion to bioethanol of 34.8% is determined for the mixture of residues. This work analyses the potential of broccoli and carrot residues for bioethanol production, either as isolated or as mixed wastes.

Indole-3-acetonitrile is a critical molecule with weed allopathic suppression function in broccoli (Brassica oleracea var. italica).

Cruciferous plants are frequently used for ecologically benign weed control in agricultural production. The varieties were the most effective, Most effective Broccoli varieties were screened using the entropy method-based topsis model at first. Result showed that Lvwawa and Lvbaoshi were most effective in allelopathic suppression on radishes. Column and thin-layer chromatography were used to extract the allelopathic compounds from broccoli residues, which contained various herbicidal active substances; among them, purified single-molecule indole-3-acetonitrile has a stronger inhibitory effect than pendimethalin (commercial herbicide). The weed inhibition rate increased with increasing broccoli residue dosage, with a 40 g/m2 broccoli residue dose yielding the highest suppression rate. Its effect was similar to that of indole-3-acetic acid. Too much of this substance leads to the plant's death. Moreover, broccoli residues had effective control effect on weeds in natural soils in greenhouse and field trials. The results demonstrated that broccoli residue could be used for weed management in field for abundant allopathic suppression molecules to weeds, and that Indole-3-acetonitrile is one of the most important allopathic molecule.

Glucosinolate-extracts from residues of conventional and organic cultivated broccoli leaves (Brassica oleracea var. italica) as potential industrially-scalable efficient biopesticides against fungi, oomycetes and plant parasitic nematodes

This study aimed to standarize a protocol for obtaining a bioactive extract from broccoli (Brassica oleracea var. italica) crop residues, that is suitable for application on an industrial scale and effective in reducing plant disease incidence. For this purpose, the influence of several extraction factors in the glucosinolate (GSL) content was studied with leaves collected from two conventional broccoli fields and two organic broccoli fields. The analysis showed that lyophilization had no influence on the GSL content. Storage of plant material under two different temperatures (− 20ºC and − 80ºC) had no influence on the GSLs content of the extracts. Phytotoxicity of the extracts was studied with six different plant seeds, and also cytotoxicity was determined with human liver cells in vitro. The extracts were phytotoxic at dilutions above 10%, while cell toxicity was low. Extracts concentrations of 0.1%, 1% and 2% were tested in vitro against eight plant pathogenic fungi and two oomycetes in solid and in liquid media. The extracts reduced the growth of several plant pathogenic fungi at 2% dilution by up to 38.37% against Alternaria alternata and up to 46.55% against Sclerotinia sclerotiorum. When combined with myrosinase enzyme the effect of the extracts was enhanced, reaching inhibition values of 67.06% against A. alternata in solid medium and 68.52% against Rhizoctonia solani in liquid medium. In contrast, the same extracts increased the growth of the plant pathogenic oomycetes Pythium ultimum and Phytophthora cactorum. The effect of the same extracts in the free leaving larvae, J2s, of the plant-parasitic nematode (PPN) Meloidogyne javanica was not obvious. Minor significant differences were obtained but with no clear dose-response in nematode mortality, and no inhibition of eggs hatching was observed. These results show the industrial potential of using broccoli residues to obtain extracts with biopesticide activity against plant pathogenic fungi.

Effect of broccoli fresh residues-based extracts on the postharvest quality of cherry tomato (Solanum lycopersicum L.) fruits

Agroindustrial residues such as cruciferous plant residues are important for postharvest treatments and of great interest because of their bioactive compounds with antimicrobial and antifungal activity, which can be used as an alternative to the use of chemical agents to treat pathogens during tomato postharvest. Cherry tomato fruit has a short shelf-life due to the action of microorganisms and high respiration rate during storage. For this reason, the effect of broccoli fresh residues-based extracts on the postharvest quality of cherry tomato fruits and their inhibition effect in vivo against Botrytis cinerea were evaluated. Extracts were obtained from fresh broccoli residues using ultrasound and different solvents (ethanol and methanol, 30% v/v), these were used as immersion treatments, and fruits were stored at 21 °C. The results showed that the application of broccoli residue extracts on cherry tomato fruits generated a decrease in weight loss and maintained firmness, color, chemical content (pH, TSS, TA, and TA/TSS ratio), phenolic compounds, and antioxidant capacity compared to untreated (control) tomato fruits. Additionally, extracts showed a fungistatic effect against Botrytis cinerea under in vivo conditions. Therefore, broccoli extracts, particularly 20 mg L−1 methanol/ultrasound, can be used as postharvest treatments for cherry tomato preservation to 36 days of storage.

Effect of incorporation of broccoli residues into soil on occurrence of verticillium wilt of spring-sowing-cotton and on rhizosphere microbial communities structure and function.

Cotton verticillium wilt (CVW) represented a typical plant soil-borne disease and resulted in widespread economic losses in cotton production. However, the effect of broccoli residues (BR) on verticillium wilt of spring-sowing-cotton was not clear. We investigated the effects of BR on CVW, microbial communities structure and function in rhizosphere of two cotton cultivars with different CVW resistance using amplicon sequencing methods. Results showed that control effects of BR on CVW of susceptible cultivar (cv. EJ-1) and resistant cultivar (cv. J863) were 58.49% and 85.96%, and the populations of V. dahliae decreased by 14.31% and 34.19%, respectively. The bacterial diversity indices significantly increased in BR treatment, while fungal diversity indices significantly decreased. In terms of microbial community composition, the abilities to recruit bacteria and fungi were enhanced in BR treatment, including RB41, Gemmatimonas, Pontibacter, Streptomyces, Blastococcus, Massilia, Bacillus, and Gibberella, Plectosphaerella, Neocosmospora, Aspergillus and Preussia. However, the relative abundances of Sphingomonas, Nocardioides, Haliangium, Lysobacter, Penicillium, Mortierella and Chaetomidium were opposite tendency between cultivars in BR treatment. According to PICRUSt analysis, functional profiles prediction showed that significant shifts in metabolic functions impacting KEGG pathways of BR treatment were related to metabolism and biosynthesis. FUNGuild analysis indicated that BR treatment altered the relative abundances of fungal trophic modes. The results of this study demonstrated that BR treatment decreased the populations of V. dahliae in soil, increased bacterial diversity, decreased fungal diversity, changed the microbial community structure and function, and increased the abundances of beneficial microorganisms.

Technoeconomic analysis of broccoli biorefineries for polyphenol extraction and biobutanol production

Fossil resources dominate the energy supply. In 2019, the total energy supply worldwide accounted for 606 exajoules (EJ), of which fossil fuels (oil, coal, and gas) had a share of 81% (490 EJ). The biorefinery concept proposes the synthesis of renewable energies as an alternative to fossil carburants. As a second-generation biofuel, biobutanol has outstanding characteristics and can be obtained from agricultural residues and organic wastes; however, its bioprocessing is not economically feasible using current methodologies. In 2021, the global production of broccoli (Brassica oleracea var. Italica) was 25.5 million tons; being the fifth top producer, Mexico generated 687,000 tons of this vegetable. In this work we propose a production design for the synthesis of biobutanol and the recovery of valuable byproducts, like high-value polyphenolic compounds, from broccoli residues, abundant in the state of Guanajuato, Mexico. For the transformation of the substrate a biochemical matrix was proposed for its composition, as well as a biotechnological route that follows a general path with the acid pretreatment of biomass, enzymatic hydrolysis, and acetone-biobutanol-ethanol (ABE) fermentation using anaerobic bacteria. The outlined biorefinery integrates conventional methods in three methodological pathways and a hybrid model for the downstream process. With the aim of visualizing the global economic performance and evaluating a possible reduction in production costs, we performed a technoeconomic analysis of the designed second generation biorefinery plant. The economic evaluation was carried out using SuperPro Designer® V 12.0. The results confirm the enormous dependence that this type of biorefinery suffers from energy demands. We found that by implementing strategic adaptations to the downstream process operating costs can be considerably reduced. However, to achieve full financial efficiency in the production of biobutanol from broccoli residues, it is necessary to deepen the research and development of innovative methods to efficiently separate and purify the final products, as well as novel methodologies for the biotransformation of the described lignocellulosic biomass along the entire technological route. We also found that there is a large opportunity in the valorization of the plentiful broccoli residues generated in the Guanajuato region.

Effects of moisture contents in incorporated residues and soil on net nitrogen mineralization in a laboratory study

AbstractIn Mediterranean climates, winters are mild, and decomposition of crop residues generally continues during the rainy winter season. The objective of this study was to determine whether letting crop residues dry before incorporation slows down net nitrogen (N) mineralization and reduces the risk of nitrate losses with rain during the winter months. Incubation experiments were performed with processing tomato (Solanum lycopersicum L.) and broccoli (Brassica oleracea L. var. italica) residues. Three residue moisture treatments, ranging from fresh to air‐dry residues, and three soil moisture levels were included in the study. Net N mineralization was observed during the first week in the broccoli treatments, whereas tomato residues led to net N immobilization. Increasing moisture of incorporated residues increased net N mineralization or immobilization. An exception was the fresh broccoli residue, which resulted in a lower net N mineralization rate than the drier residues, likely due to anaerobic microsites created by high microbial activity. The moisture content of the residues only had a short‐term effect on N turnover. Over the 12 wk of the incubations, the incorporation of both residues resulted in net N mineralization when compared with the unamended control. Nitrogen mineralization increased as soil moisture content increased and approached field capacity. These results indicate that residue moisture at the time of incorporation will not affect N mineralization beyond the initial weeks.

Integrating broccoli rotation, mustard meal, and anaerobic soil disinfestation to manage verticillium wilt in strawberry

Verticillium wilt, a disease caused by the fungus Verticillium dahliae, affects a vast range of crops, including strawberries. A field trial was established to evaluate the effect of broccoli in rotation prior to strawberries, anaerobic soil disinfestation (ASD), and mustard cake (MC) alone and in combination at suppressing V. dahliae. Broccoli, cauliflower and fallow plots were established in year 1, followed by strawberry, winter cover crop, and lettuce across all plots over the next two years. ASD and ASD + MC improved strawberry yields compared to the untreated control (UTC). At the end of the harvest season, V. dahliae infection rates in strawberry crowns were lower in the ASD and ASD + MC treatments compared to the UTC. After harvest of the lettuce crop, the number of V. dahliae microsclerotia in soil treated previously with ASD was lower than in the UTC. Broccoli residue incorporation had no effect and MC alone a limited effect on strawberry yields, V. dahliae in strawberry crowns, and soil microsclerotia levels at lettuce harvest. All rotations treated with ASD showed higher total net returns despite the higher cost of treatments. The ability of ASD to control V. dahliae and its persistent suppressive effect on soil microsclerotia levels have important economic implications for growers.

Effects of Bacillus subtilis NCD-2 and broccoli residues return on potato Verticillium wilt and soil fungal community structure

Potato Verticillium wilt is an economically important disease that significantly decreases tuber yield. Biological control is an effective approach for controlling potato Verticillium wilt. The objective of this study was to evaluate the effects of treatment with Bacillus subtilis NCD-2 (BS), broccoli residues (BR), and combination among them (BB) on potato Verticillium wilt and the soil fungal community structure. Field experiments demonstrated that BS, BR and BB successfully suppressed potato Verticillium wilt, achieving control effects of 32.25%, 48.15%, and 37.85%, respectively. Compared to the untreated control, potato yield increased by 10.38%, 16.82% and 27.12% after the treatments of BS, BR and BB, respectively. Moreover, the BS treatment did not decrease the rhizosphere V. dahliae population, which was significantly decreased by BR (19.08%) and BB (30.46%). Illumina MiSeq analysis showed that soil fungal diversity in the rhizosphere was decreased under BS, BR and BB. Principal component and heatmap analyses showed that BS exerted a similar effect on the fungal community structure to the blank control. However, BR and BB greatly changed the fungal community structure. Moreover, the relative abundance of beneficial microbes such as Chaetomium and Mortierella was higher in the BS and BB soils than in the control. Redundancy analysis (RDA) showed that the fungal community structure under BR and BB was positively correlated with SOM, pH, AP and IP, while the opposite trend was observed under BS. The results suggested that BS seed treatment and BR return could be a useful strategy for potato production in sustainable agriculture; this research may provide a theoretical basis for understanding the mechanism of the ecological control of potato Verticillium wilt.

Effect of Broccoli Residue and Wheat Straw Addition on Nitrous Oxide Emissions in Silt Loam Soil

Nitrous oxide (N2O) is one of the main greenhouse gases and its emissions from vegetable production systems have brought a sustainability challenge. The objective of this study was to evaluate the potential of reducing N2O emissions from silt loam soil by mixing nitrogen (N)-rich broccoli (Brassica oleracea var. italica) residue with wheat straw or water-washed wheat straw. An experiment was conducted in randomized complete block design with five treatments; unamended or control (BS), wheat straw (+S), broccoli residue (+CR), broccoli residue and wheat straw (+CR+S) and broccoli residue and washed wheat straw (+CR+Sw) and was replicated four times. The +CR and +S were added at the rate of 3.5 kg and 2.0 kg fresh matter m−2 and their mixtures, +CR+S and +CR+Sw, were incorporated in 3.5 kg of silt loam soil at 60% water-filled pore space (WFPS) and packed in soil microcosms. Nitrous oxide emissions were measured once a day during the 14-day of study period. Daily fluxes of N2O were found to be reduced on +CR+W and +CR+Sw when compared to single-amended +CR treatment. Similarly, N2O fluxes on +CR+Sw (2772 µg N m−2 h−1) were significantly lower than +CR+S (3606 µg N m−2 h−1) soon after the amendment but did not vary significantly thereafter. Moreover, the amendment mixture, +CR+S and +Cr+Sw, resulted in lower net N2O emissions by 73.3% and 74.2%, respectively, relative to +CR treatment. While the results clearly suggest that the +CR+S or +CR+Sw reduced N2O emissions, it necessitated further studies, possibly by increasing the frequency of sampling to clarify if washed wheat straw would further mitigate N2O emissions from the vegetable production system.

Are substrate-mediated microbial community shifts the future of soilborne disease management?

The loss of methyl bromide as a soil fumigant, the limited efficacy of alternative fumigants, and the emergence of new diseases has necessitated fumigant-based crop production systems to radically restructure for continued productivity. In the coastal valleys of central California, the principal objective of soil fumigation has been to confine Verticillium dahliae population densities to levels below the threshold at which yield losses occur. The wide-spread adoption of alternative fumigants has coincided with the emergence of soilborne diseases caused by Fusarium oxysporum f. sp. fragariae and Macrophomina phaseolina. The ability to harness native soil microbiomes to manage plant pathogens remains a promising but relatively unexplored area. Our studies have focused on substrate-mediated changes in soil prokaryote communities with the goal to convert Verticillium wilt-conducive soils to Verticillium wilt-suppressive soils. The effect of broccoli residue and crustacean meal on soil microbiomes and suppression of Verticillium wilt were studied in soils with distinct land-use histories: intense agriculture, transition from pasture to agriculture, and native, undisturbed soil. Regardless of the soil type, the organic inputs significantly reduced V. dahliae microsclerotia and wilt incidence and severity on eggplants in the greenhouse, and these reductions were correlated with an increase in the proportion of known fungal antagonists. Prokaryote communities identified were distinct in the wilt-suppressive soils as compared to the wilt-conducive soils. Three cycles of inputs nearly eliminated the pathogen in all three soil types. This approach was validated in a 12.2 ha commercial lettuce field in Salinas Valley with a known history of severe Verticillium wilt. After an 18-month broccoli-Romaine lettuce-broccoli rotation including amending soil with crustacean meal before each crop, significant reductions in V. dahliae microsclerotia density were achieved. These studies demonstrated the potential for harnessing native soil microbiomes to manage plant pathogens using specific carbon sources that favor fungal antagonists. This approach worked in soils with various land use and disease incidence histories and was validated in a commercial lettuce field in Salinas Valley, California.

Assessment of crop residue and palm shell biochar incorporation on greenhouse gas emissions during the fallow and crop growing seasons of broccoli (Brassica oleracea var. italica)

The impact of broccoli crop residues on greenhouse gas (GHG) emissions may vary with post-harvest management. The incorporation of biochar together with broccoli residues could have a GHG mitigation potential in soil. A field experiment was conducted to evaluate the combined effect of broccoli crop residues and palm shell biochar (PSB) incorporation on GHG emissions during the fallow (post-harvest) and crop growing seasons of broccoli. We also evaluated the plant biomass, N uptake, and soil chemical properties after harvest. The treatments included; No-residues (NR), Residues (R), Residues + 10 t ha−1 PSB (R10), Residues + 20 t ha−1 PSB (R20) and Residues + 40 t ha−1 PSB (R40), arranged in a completely randomized block design. The fallow season had significantly higher GHG emissions than the crop growing season. Incorporation of crop residues in soil significantly increased N2O and CO2 emissions but did not significantly affect CH4 emissions when compared to those of the NR treatment. PSB amendment did not significantly affect N2O, CO2 and CH4 emissions from crop residues and also the biomass and N uptake of the crop residues remaining after broccoli harvest. The application of PSB at 40 t ha−1 significantly increased the total N, total C, C/N ratio and exchangeable K but did not significantly affect soil pH, EC, available P, exchangeable Ca and Mg, and CEC. The large amounts of N2O and CO2 emissions emitted from broccoli crop residues during the fallow season may necessitate higher biochar application rates to achieve the GHG mitigation potential of biochar while maintaining a high soil nutrient status. The combined incorporation of broccoli crop residues with biochar requires further evaluation in terms of GHG emissions, soil nutrient status and broccoli crop yield in different soil types and tillage systems.

Cultural, biological and chemical control of the white rot fungus (Sclerotium cepivorum, Berk) in onions (Allium cepa) in Arequipa´s countryside

This experiment was carried out at the province of Arequipa, to determine broccoli residual effects on the sclerotia population of Sclerotium cepivorum on the soil and determine the best fungicides and biocontrol agents on the biggest red onion production. In two field areas infected with Sclerotium cepivorum , soil samples were carried out to determine the number of sclerotia at the beginning and the end of the trial. One area received broccoli residues before treatment installation. The experiment had a laboratory and a field phase. The block design was used completely randomized (DBCA), using seven fungicide treatments (T1) control, Iprodione (T2), Thiabendazole (T3), Boscalid (T4), Carbendazim (T5), T harzianum (T6), Bacillus subtilis (T7). Both areas received the same treatments. The density of sclerotia in the soil was not significant between these areas. However, the addition of broccoli had lower percentages of incidence and severity and higher yields in all treatments. At the area that received broccoli, the Boscalid (T4) and the Iprodine (T2) fungicide were highlighted with 43.33 T/ha and 28.33 T/ha, respectively; the area without broccoli, the T4 with 38.33 T/ha and T2 with 25.56 T/ha. T5 (Carbendazim) had the lowest yield: 15.00 T/ha without broccoli and 19.58 T/ha with broccoli.

Fermented Broccoli Residue Reduced Harmful Bacterial Loads and Improved Meat Antioxidation of Free-Range Broilers

SUMMARY Free-range animals with unavoidable exposure to dirt and dung easily carry harmful bacteria, but little is known about the effect of dietary fermented supplement on bacterial loads. This study investigated the effect of fermented broccoli residue (FB) on the growth performance, harmful bacterial loads, and meat antioxidation of free-range broilers from 42 to 84 d of age. Six free-range pens (n = 40 chickens per pen) were randomly assigned to 1 of 3 treatments containing FB at 0 (control), 5, or 10%. The results showed that the 2 levels of FB did not affect growth performance, but decreased (P

Effect of Broccoli Residues Fermented with Probiotics on the Growth Performance and Health Status of Broilers Challenged with Clostridium Perfringens

This study aimed at investigating the effects of broccoli residues fermented with probiotics (BF) on the growth performance, immunity, and gut health in broilers challenged with Clostridium perfringens (C. perfringens). A total of 600 broilers (one day old) were randomly allotted into five treatments with six replicates of 20 birds each and were reared until 42 days of age. The treatments included a positive control (PC, fed a basal diet and reared on uncontaminated litter), a negative control (NC, birds reared on litter contaminated with C. perfringens and fed a basal diet), and NC plus BF at 25, 50 or 75 g/kg of diet. The BF contained yeast 3.1 × 107cfu/g, lactic acid bacteria 9.5 × 106cfu/g and Bacillus subtilis 3.5 × 106cfu/g. Birds in the NC group showed lower (p<0.05) feed intake and body weight gain, whereas BF supplementation recovered (p<0.05) the growth performance to the levels of PC group. Dietary BF at 50and 75 g/kg reduced (p<0.05) broiler mortality. Similarly, compared to the NC group, BF increased (p<0.05) immune organ weights and serum immunoglobulins A, G, and M to the levels of PC group. The ileal populations of Escherichia coli and Gram-negative bacteria were decreased (p<0.05) by BF to the levels of PC, and C. perfringens was also decreased (p<0.05) by BF. The serum profiles of mono- and di-amine oxidase were decreased (p<0.05) by BF. BF at 75 g/kg reduced (p<0.05) monoamine oxidase compared with the other BF doses. The results suggest that broccoli residues fermented with probiotics can be a novel biological feed additive to protect the performance and health of broilers against C. perfringens infection.

Soil Microbiomes Associated with Verticillium Wilt-Suppressive Broccoli and Chitin Amendments are Enriched with Potential Biocontrol Agents.

Two naturally infested Verticillium wilt-conducive soils from the Salinas Valley of coastal California were amended with disease-suppressive broccoli residue or crab meal amendments, and changes to the soil prokaryote community were monitored using Illumina sequencing of a 16S ribosomal RNA gene library generated from 160 bulk soil samples. The experiment was run in a greenhouse, twice, with eggplant as the Verticillium wilt-susceptible host. Disease suppression, plant height, soil microsclerotia density, and soil chitinase activity were assessed at the conclusion of each experiment. In soil with high microsclerotia density, all amendments significantly reduced Verticillium wilt severity and microsclerotia density, and increased soil chitinase activity. Plant height was increased only in the broccoli-containing treatments. In total, 8,790 error-corrected sequence variants representing 1,917,893 different sequences were included in the analyses. The treatments had a significant impact on the soil microbiome community structure but measures of α diversity did not vary between treatments. Community structure correlated with disease score, plant height, microsclerotia density, and soil chitinase activity, suggesting that the prokaryote community may affect the disease-related response variables or vice versa. Similarly, the abundance of 107 sequence variants correlated with disease-related response variables, which included variants from genera with known antagonists of filamentous fungal plant pathogens, such as Pseudomonas and Streptomyces. Overall, genera with antifungal antagonists were more abundant in amended soils than unamended soils, and constituted up to 8.9% of all sequences in broccoli+crabmeal-amended soil. This study demonstrates that substrate-mediated shifts in soil prokaryote communities are associated with the transition of Verticillium wilt-conducive soils to Verticillium wilt-suppressive soils, and suggests that soils likely harbor numerous additional antagonists of fungal plant pathogens that contribute to the biological suppression of plant disease.

Effects of molasses on the fermentation characteristics of mixed silage prepared with rice straw, local vegetable by-products and alfalfa in Southeast China

This experiment was conducted to study the effect of molasses on the fermentation characteristics of mixed silage ensiled rice straw and vegetable by-products with alfalfa. Mixture (202 g kg−1 dry matter (DM)) consisting of rice straw, broccoli residue and alfalfa at the ratio of 5:4:1 was ensiled with three experimental treatments: (1) no additives (control); (2) molasses at 2.5% (M1); (3) molasses at 5% (M2) on a fresh matter basis of mixture, respectively. All treatments were packed into laboratory-scale silos, and three silos per treatment were sampled on days 1, 3, 5, 14 and 30. The result showed that the pH value of all mixed silages decreased gradually with the time of ensiling except for the control silage, in which a significant increase (P <0.05) on day 30 occurred. The lactic acid content increased gradually with the time of ensiling and reached the highest value on day 14, and a marked decrease (P <0.05) was found in the control silage on day 30. The changes of acetic acid content showed similar pattern with lactic acid content. A trace amount of propionic and butyric acid contents were found in the three mixed silages during the fermentation period. Comparing to the control, M1 and M2 treatments improved the fermentation quality of mixed silages as indicated by higher (P <0.05) lactic acid contents and lower (P <0.05) pH and ammonia-N contents. The Flieg points also showed that M1 and M2 silages were well preserved, whereas the control silage had a bad quality. Overall, the findings of this study suggested that adding molasses could improve fermentation quality of mixed silage, and M1 was more suitable for practical application.

Larval Performance and Adult Attraction of Delia platura (Diptera: Anthomyiidae) in a Native and an Introduced Crop.

Delia platura Meigen is an important pest in crops around the world. Its host range includes almost 50 species, and it can develop in soil organic matter. In Ecuador, D. platura is a serious problem for the crop, Lupinus mutabilis Sweet (Chocho), and it also attacks broccoli (Brassica oleracea L.). After broccoli is harvested, crop residue is mixed with soil or collected and stored close to Chocho fields. The objectives of this study were to determine the adaptive responses of larvae reared on different hosts and whether D. platura females are preferentially attracted to germinating L. mutabilis seeds or broccoli residue. Accordingly, larval performance and attraction of female D. platura reared on broccoli residue and L. mutabilis seeds were evaluated. The number of larvae, pupae, and adults were higher when reared on broccoli. Conversely, pupal weight was higher and time from larva to pupa, pupa to adult, and total life cycle were longer in flies reared on L. mutabilis. Although D. platura developed more quickly on broccoli, L. mutabilis was also a good host since pupae were heavier compared with flies reared on broccoli. Delia platura females reared on broccoli preferred broccoli residue to L. mutabilis in an olfactometer. Volatiles from broccoli residue in soil may attract D. platura females and stimulate oviposition on L. mutabilis seeds. Environmentally benign production of L. mutabilis crops with minimal insecticide applications may require the elimination of fresh broccoli residue as fertilizer in soils where L. mutabilis is cultivated.

Nitrogen Dynamics of Cole Crop Production: Implications for Fertility Management and Environmental Protection

Intensive production of cool-season vegetables has contributed to nitrate pollution of groundwater along the central coast of California. Broccoli (Brassica oleracea L. var. italica), cabbage (Brassica oleracea L. var. capitata), and cauliflower (Brassica oleracea L. var. botrytis) are important crops in this region, but few data are available regarding the nitrogen dynamics of these cole crops under current production practices, and whether those practices are protective of groundwater. Monitoring was conducted in 14 commercial broccoli, 8 cabbage, and 8 cauliflower fields evaluating crop growth, rooting depth, N uptake and partitioning, patterns of soil N availability, and current N fertilization and irrigation practices. Aboveground biomass N at harvest averaged 367, 367, and 319 kg·ha−1 for broccoli, cabbage, and cauliflower, respectively, with mean N fertilization rates of 209, 280, and 256 kg·ha−1. The relatively small fraction of biomass N removed at harvest with cauliflower (23%) and broccoli (31%) resulted in a low partial N balance (PNB) of 30% and 57%, respectively, compared with cabbage (PNB of 70%). Rooting depth increased throughout the growing season, reaching ≈1 m by harvest, with about 70% of roots located in the top 40 cm in all crops. Soil mineral N (SMN; 0- to 30-cm depth) varied among fields, with the early-season median value of 18 mg·kg−1 declining to 5 mg·kg−1 by harvest. Seasonal N application was not correlated with early-season SMN. Irrigation applied, predominately through sprinklers, averaged &gt;200% of estimated crop evapotranspiration. Substantial N mineralization from broccoli residue was observed within 2–3 months following fall incorporation, with potential NO3-N leaching losses exceeding 100 kg·ha−1 in both monitored fields. We conclude that improved irrigation management, adjusting N rates based on residual SMN, and employing a remediation practice such as cover cropping to limit winter NO3-N leaching losses could substantially improve N efficiency in cole crop production.