Vegetable Production Systems Research Articles

COMPARING PROFITS OF ORGANIC AND NON-ORGANIC FLUTED PUMPKIN AMONG SMALLHOLDER FARMERS IN DELTA STATE, NIGERIA

The study was conceptualized to compare profits of organic and non-organic farming technologies among smallholder fluted pumpkin farmers in Delta State, Nigeria. A multistage sampling technique was employed in the selection of location and respondents. The data were collected using structured questionnaire from 240 organic and non-organic smallholder fluted pumpkin farmers. Data obtained was analyzed using descriptive statistics and enterprise budgeting method. Results indicated that the profit realized by organic and non-organic (conventional system) fluted pumpkin farmers was N561,850 and N222,130 per farmer per plot, respectively. The study concluded that organic system of vegetable production was more profitable than conventional system. It was recommended that farmers should concentrate more on organic system of fluted pumpkin production to enable good profit.

Innovative Controlled-Release Polyurethane-Coated Urea Could Reduce N Leaching in Tomato Crop in Comparison to Conventional and Stabilized Fertilizers

Large amounts of fertilizers are being used in agriculture to sustain growing demands for food, especially in vegetable production systems. Soluble fertilizers can generally ensure high crop yields, but excessive leaching of nutrients, mainly as nitrate, can be a major cause of water pollution. Controlled-release fertilizers improve the nutrient use efficiency and lower the environmental hazard, usually without affecting the production. In this study, an innovative controlled-release coated urea fertilizer was compared to conventional nitrogen (N) fertilizers and a soluble ammonium-based fertilizer containing a nitrification inhibitor, in a round table tomato cultivation. Both the water and N balance were evaluated for each treatment, along with the yield and quality of the production. The experiment was repeated in three different seasons (spring, autumn and summer-autumn) in a glasshouse to prevent the effect of uncontrolled rainfall. The results indicated that N leaching decreased by increasing the percentage of coated urea. The application of at least 50% total N as coated urea strongly reduced N leaching and improved N agronomic efficiency in comparison with traditional fertilizers, ensuring at the same time a similar fruit production. Due to reduced leaching, the total N amount commonly applied by growers could be lowered by 25% without detrimental effects on commercial production.

The application of Bacillus Megaterium alters soil microbial community composition, bioavailability of soil phosphorus and potassium, and cucumber growth in the plastic shed system of North China

The long-term continuous mono-cropping and application of large amount of chemical fertilizers have led to a dramatic degradation of soil quality in the intensive vegetable production system. It is important to develop more sustainable, environmentally friendly and high-efficiency agroecosystems for vegetable production in plastic shed systems. Field experiments were performed to explore the impacts of Bacillus megaterium application on cucumber yields, the bioavailability of soil phosphorus (P) and potassium (K), properties of soil microbial communities in a plastic shed production system with cucumber mono-cropped for more than 15 years. The field trails were set up with four treatments of conventional fertilization as control (CON), conventional fertilization with Bacillus megaterium (CON + BM), conventional fertilization reduced by 10 % P and 10 % (or 5 %) K from chemical fertilizer with Bacillus megaterium (CON + BM - PK1), conventional fertilization reduced by 20 % P and 20 % (or 10 %) K from chemical fertilizer with Bacillus megaterium (CON + BM - PK2). Results illustrated that CON + BM treatment significantly increased the cucumber yields by 11.8 %–15.2 % and P and K accumulation in cucumber fruits and roots by 27.5 %–46.1 % and 17.8 %–45.1 %, respectively. The treatments of CON + BM - PK1 and CON + BM - PK2 did not decrease the yields and quality of cucumber, and the bioavailability of soil P and K compared with CON + BM. Moreover, the strain of Bacillus megaterium can efficiently colonize the soil at the early stage of inoculation and improved the richness of soil bacterial and fungal communities significantly. High-throughput sequencing identified that the application of Bacillus megaterium did not change the compositions of the predominant bacterial phyla Proteobacteria, Acidobacteria, Actinobacteria, Firmicutes, and predominant fungal phylum Ascomycota in soil, but increased the relative abundances of the beneficial bacterial genera and fungal orders and suppressed the development of pathogenic bacterial genus significantly. Principal coordinate analysis revealed that the structures of soil bacterial and fungal communities in the CON + BM treatment were dramatically separated from CON at the early stage of inoculation. Moreover, soil pH, available K (AK), total P (TP), and total K (TK) were dramatically related to the changes of soil bacterial community structure, while soil AK and TK were dramatically linked to the variations of soil fungal community structure. The findings indicated that the application of Bacillus megaterium might contribute to the development of a more sustainable production system of vegetables in plastic shed via improving the properties of soil microbial community and the bioavailability of soil P and K.

Comprehensive assessment of the effects of nitrification inhibitor application on reactive nitrogen loss in intensive vegetable production systems

Previous studies regarding environmental impacts of nitrification inhibitors (NIs) in intensive vegetable production systems mainly focused on the fate of individual nitrogen (N) compounds. Due to the influence of various N-dynamic pathways on one another, systematic observations, taking into account all key component processes, must be carried out to achieve practically useful recommendations. As well, the mechanisms of how NI application leads to increasing vegetable yields are not well understood. Therefore, we conducted a field experiment with three leading vegetable crops (lettuce, celery, and tomato), and two urea N input rates, without (N1, N2) or with a nitrification inhibitor, 2-chloro-6-(trichloromethyl)-pyridine (CP) (N1 + CP, N2 + CP), to evaluate the comprehensive effects of CP on reactive-N emission in these intensive vegetable production systems, with a focus on leaching, ammonia (NH3) volatilization, and nitrous oxide (N2O) emission, and to clarify the possible mechanisms by which CP affects vegetable yield. The results show that CP application significantly decreased (p < 0.05) N leaching by 36.9, 26.9, and 28.4 %, soil residual NO3-N contents by 34.1, 43.7, and 43.9 %, N2O emission by 46.4, 77.2, and 36.9 %, and significantly increased (p < 0.05) NH3 volatilization by 33.5, 56.3, and 308.1 % in the lettuce, celery, and tomato seasons, respectively, while having no significant effect on yield at the typical N-application rate (N2). Under 60 % of the typical N-application rate (N1), CP addition significantly increased (p < 0.05) yield and N-use efficiency (NUE) over the three-season period by 23.9 and 55.1 %, respectively, significantly reduced (p < 0.05) N2O emission by 43.5 %, while having no significant effect on the other three observed N processes. In a lettuce-celery-tomato rotation, compared with the typical N-application rate (N2), 60 % of the typical N-application rate with CP addition (N1 + CP) significantly increased (p < 0.05) yield and NUE by 37.1 and 214 %, and decreased (p < 0.05) soil residual NO3-N contents, N leaching, and N2O emission by 70.9, 51.1, and 69.6 %, respectively, and had no significant effect on NH3 volatilization. Furthermore, the distribution analysis of N derived from 15N-labeled urea in tomato aboveground suggested that CP application significantly decreased (p < 0.05) N allocation to stems and leaves by 12.1 and 9.7 %, and significantly increased (p < 0.05) N allocation to fruits by 31.2 %, averaged over 60 % and 100 % N treatments. Application of CP increased N storage in fruits and benefited yield.

Managing irrigation under pressure: How supply chain demands and environmental objectives drive imbalance in agricultural resilience to water shortages

Food production systems worldwide are increasingly exposed to water shortage shocks. Social-ecological resilience theory provides insights into the qualities which confer production systems with the capacity to absorb shocks and persist, undertake adaptations and ultimately achieve desirable transformations. Combining findings from the analysis of a set of 15 semi-structured interviews and 92 survey responses from growers in the UK, this paper uses resilience theory to explore the factors affecting exposure to the risk of water shortages, and management responses, within outdoor field vegetable production systems that depend on supplemental irrigation. The findings confirm that growers predominantly aim to build resilience by seeking to maintain a buffer or ‘headroom’ in their water resources to minimise the possibility that a shortage will disrupt their output of marketable produce and/ or lead to financial loss. This buffering strategy confers robustness by increasing system redundancy (availability of spare resources). But building-in redundancy conflicts with regulatory and supply chain pressures to maximise water and production efficiency respectively. Whilst stability of supply to consumers is, for the most-part, achieved, the discrepant pursuits of robustness and efficiency lock agricultural systems into increasingly rigid production and sales pathways, limiting capacities for adaptation and transformation - dimensions of resilience which permit successful system evolution in the context of more extreme shocks and stresses.

Modeling the effects of long-term reduced N application on soil N losses and yield in a greenhouse tomato production system

Overuse of N fertilizer in intensive greenhouse vegetable production systems (GVPS) seriously affects soil and water environment. Quantifying soil N dynamics and plant growth is crucial for developing sustainable N management practices. A long-term greenhouse tomato experiment, including 13 tomato growth seasons (2004–2010) and three different nitrogen (N) management practices (conventional N management, CN; reduced N management, RN; and manure N management, MN), was conducted in this study. Agricultural system model (WHCNS_Veg) was adopted to simulate and analyze the effects of different long-term N fertilization regimens on N loss and tomato yield. The calibration and evaluation of the model showed fairly satisfactory simulation in soil water content, soil nitrate concentration, crop N uptake, and fresh marketable tomato yield; the values of the normalized root mean square error (NRMSE) were 15.4%, 42.9%, 21.2%, and 7.7%, respectively, and the values of index of agreement (IA) were 0.85, 0.62, 0.96, and 0.97, respectively. Different N management practices did not significantly affect the tomato yield. However, the long-term high rates of chemical N application in CN treatment significantly increased soil N accumulation, thereby increasing N loss. The simulated N losses caused by leaching, denitrification, and ammonia volatilization under the reduced N treatments (RN and MN) were decreased by 66.8%, 56.8%, and 83.2% compared to those of CN treatment, respectively. Among different N management practices, manure N management showed a relatively high N use efficiency and maintained a high tomato yield. And the optimal manure N application rate approximately 400 kg N ha−1 yr−1 was recommended to maximize farmers' income. The results not only provide decision supports for local farmers' N management, but also policy making of government for sustainable development of greenhouse tomato production in the region.

Aggregate-associated changes in nutrient properties, microbial community and functions in a greenhouse vegetable field based on an eight-year fertilization experiment of China

Soil aggregation, microbial community, and functions (i.e., extracellular enzyme activities; EEAs) are critical factors affecting soil C dynamics and nutrient cycling. We assessed soil aggregate distribution, stability, nutrients, and microbial characteristics within >2, 0.25–2, 0.053–0.25, and <0.053 mm aggregates, based on an eight-year field experiment in a greenhouse vegetable field in China. The field experiment includes four treatments: 100% N fertilizer (CF), 50% substitution of N fertilizer with manure (M), straw (S), and manure plus straw (MS). The amounts of nutrient (N, P2O5, and K2O) input were equal in each treatment. Results showed higher values of mean weight diameter in organic-amended soils (M, MS, and S, 2.43–2.97) vs. CF-amended soils (1.99). Relative to CF treatment, organic amendments had positive effects on nutrient (i.e., available N, P, and soil organic C (SOC)) conditions, microbial (e.g., bacterial and fungal) growth, and EEAs in the >0.053 mm aggregates, but not in the <0.053 mm aggregates. The 0.25–0.053 mm aggregates exhibited better nutrient conditions and hydrolytic activity, while the <0.053 mm aggregates had poor nutrient conditions and higher oxidative activity among aggregates, per SOC, available N, available P, and a series of enzyme activities. These results indicated that the 0.25–0.053 mm (<0.053 mm) aggregates provide suitable microhabitats for hydrolytic (oxidative) activity. Interestingly, we found that hydrolytic and oxidative activities were mainly impacted by fertilization (58.5%, P<0.01) and aggregate fractions (50.5%, P<0.01), respectively. The hydrolytic and oxidative activities were significantly (P<0.01) associated with nutrients (SOC and available N) and pH, electrical conductivity, respectively. Furthermore, SOC, available N, and available P closely (P<0.05) affected microbial communities within >0.25, 0.25–0.053, and <0.053 mm aggregates, respectively. These findings provide several insights into microbial characteristics within aggregates under different fertilization modes in the greenhouse vegetable production system in China.

Leaching loss of dissolved organic nitrogen from cropland ecosystems

Although widely studied in grassland and forest ecosystems, dissolved organic nitrogen (DON), an important form of nitrogen (N) lost through leaching, has received little attention in cropland ecosystem research. A global literature review and partial least squares path modeling (PLS–PM) were adopted to assess the quantity and composition of N leaching loss under different cropping systems, soil types, and management practices, as well as to identify the major factors controlling DON leaching. Annual total dissolved nitrogen (TDN, organic + inorganic N) leaching under different cropping systems ranged from 4.0 to 383.2 kg N ha−1. Vegetable and rice production systems showed the greatest and least TDN leaching, respectively. Across different cropping systems, DON accounted for 4.7%–34.9% of TDN in leachate. The NH4 +–N form of N leaching is negligible in most upland cropping systems (&lt;2.3%), but not so in lowland rice systems. The largest ratio of DON leaching to TDN leaching was found in a rice–wheat rotation (34.9%). Catch crop slightly increased DON leaching; however, it greatly decreased TDN leaching. Cropping systems in which animal manure or plant compost was applied or lowland rice was included showed a relatively high DON leaching ratio. Accordingly, in investigating DON leaching, more attention should be focused on cropping systems with manure application or lowland rice systems. Compared with climatic conditions and soil properties, field management practices (irrigation, chemical N input, and manure amendments) proved to be the factors most strongly influencing DON leaching. This suggests that optimizing water and N management practices is the most effective way of reducing the risk of DON leaching and increasing N use efficiency, particularly for vegetable and rice production systems.

Irrigation with Magnetized Water Affects the Soil Microenvironment and Fruit Quality of Eggplants in a Covered Vegetable Production System in Shouguang City, China

The present study aimed to explore the mechanisms and soil properties of eggplant production and quality, as well as the bacterial community structure, soil physico-chemical properties, eggplant growth properties, and nutrient contents. A field experiment was performed in a seasonal crop of eggplants irrigated with magnetized water (MW) and nonmagnetized water (NMW). A magnetic field was used for water treatment in the MW groups. The soil nutrient contents as well as soil enzyme activities were significantly increased in the MW treatment compared with those in the NMW treatment. After irrigation with MW, the abundance of Proteobacteria in the soil significantly increased, while that of Firmicutes decreased in comparison with the NMW treatment. The bacterial diversity indexes operational taxonomic unit (OTU), Chao1 and ACE revealed increases of 3~24%. Additionally, the MW treatment increased the length, width, and fresh weight of the eggplant leaves by 17~29%, while the fruit length and width and the single fruit weight increased by 5~16%. The contents of vitamin C and organic acids in eggplant fruit in the MW treatment markedly increased by 25~34% compared with those in the NMW treatment. Likewise, the contents of mineral elements in the treated eggplants exhibited marked increases compared with the levels in the NMW treatment. Irrigation with MW had the potential to improve soil quality and change the community structure of the bacteria. Moreover, irrigation with MW could improve eggplant growth and output, hence promoting fruit quality. These results could provide a theoretical basis for the application of magnetics for improving crop production.

AGRONOMIC PERFORMANCE OF ROCKET AS A FUNCTION OF PHOSPHORUS FERTILISATION IN A P-RICH SOIL1

ABSTRACT In intensive vegetable production systems, it is natural to increase nutrient contents in the soil due to the frequent fertiliser applications, especially phosphorus (P). There are few studies on the response of vegetables to phosphate fertilisation under such conditions. In this context, the objective of this study was to evaluate the agronomic performance of rocket as a function of phosphorus fertilisation in a P-rich Rhodic Eutrudox soil. Five P doses (0, 50, 100, 200, and 300 kg ha-1 P2O5) were evaluated in a randomised complete block design with four replicates. Maximum soil P content and shoot P content at harvest were obtained at a dose of 300 kg ha-1 P2O5. Rocket responded negatively to P fertilisation. The increase of P doses promoted the decrease of height and yield of the crop.

Organic Amendments for Pathogen and Nematode Control.

The loss of methyl bromide as a soil fumigant and minimal advances in the development and registration of new chemical fumigants has resulted in a resurgence of interest in the application of organic amendments (OAs) for soilborne plant pathogen and plant-parasitic nematode management. Significant progress has been made in the characterization of OAs, application of strategies for their use, and elucidation of mechanisms by which they suppress soilborne pests. Nonetheless, their utility is limited by the variability of disease control, expense, and the logistics of introducing them into crop production systems. Recent advances in molecular techniques have led to significant progress in the elucidation of the role of bacteria and fungi and their metabolic products on disease suppression with the addition of OAs. Biosolarization and anaerobic soil disinfestation, developed to manipulate systems and favor beneficial microorganisms to maximize their impact on plant pathogens, are built on a strong historical research foundation in OAs and the physical, chemical, and biological characteristics of disease-suppressive soils. This review focuses on recent applications of OAs and their potential for the management of soilborne plant pathogens and plant-parasitic nematodes, with emphasis primarily on annual fruit and vegetable production systems.

Variations in nitrous oxide emissions as manipulated by plastic film mulching and fertilization over three successive years in a hot pepper-radish rotated vegetable production system

Plastic film mulching (FM) is widely applied in agro-ecosystems to improve soil hydrothermal conditions for better crop productivities. However, effects of such FM practices on nitrous oxide (N2O) emissions are not well known in high nitrogen (N) input vegetable fields. Using static chambers under no-mulching (NM) and FM with four N application rates N2O emissions were monitored in a hot pepper (Capsicum annuum)-radish (Raphanus sativus) rotation in southwest China over three years (Cycle 1, 2 and 3) from May 2014 to February 2017. These four N application rates for each vegetable crop were 0, 150, 300 and 450 kg N ha−1 and 0, 100, 200 and 300 kg N ha-1 in the respective hot pepper and radish seasons. Compared to NM, FM insignificantly reduced N2O emissions in the hot pepper season owing to lower soil moisture, while significantly increased N2O emissions in the radish season owing to higher soil NH4++NO3− and temperature. Additionally, FM had no remarkable effects on N2O EFs or crop yields of hot pepper or radish. N application exerted stronger effects on N2O emissions under FM and NM in Cycle 1 than in other two cycles during the hot pepper season owing to higher temperature and rainfall, resulting in very high N2O EFs (2.56 %–7.43 %). The average seasonal EF was 1.52 % (0.15 %–7.43 %), while the average annual EF was 1.74 % (0.16 %–5.32 %), which was comparable to the 2006 IPCC defaulted of 1.00 %. Yield-scaled N2O emissions under FM were significantly increased in the radish season, but not in the hot pepper season. Additionally, N application remarkably increased N2O emissions and crop yields in the hot pepper season, with a bigger effect on N2O emissions than on crop yields, leading to increased yield-scaled N2O emissions with increasing N application between 0 and 450 kg N ha-1. Moreover, the stimulation effect of N application on crop yield was strongest under 150 kg N ha-1 with lower yield-scaled emissions. In addition, N application remarkably increased N2O emissions and crop yields, but were more prominent on crop yields than N2O emissions during the radish season, resulting in insignificant increase of yield-scaled N2O emissions between 0 and 300 kg N ha-1. Our results demonstrated that no-mulching with 150 or 300 kg N ha-1 fertilization in the hot pepper or radish season is a more suitable agronomic practice to simultaneously mitigate N2O emissions while increasing crop yields in subtropical vegetable fields.

Effects of maize as a catch crop on subsequent garland chrysanthemum and green soybean production in soil with excess nitrogen

Greenhouse vegetable cultivation is often associated with the rapid accumulation of nitrate in soils. Therefore, N management strategies are needed for greenhouse vegetable production systems. The objective of the present study was to evaluate the effects of a summer catch crop on vegetable crop yields. Maize, as an N catch crop, was planted in leafy vegetable (garland chrysanthemum) and fruit vegetable (green soybean) greenhouse cropping systems during the summer of two consecutive years. Maize removed 4.9–11.8 g N m−2 from the greenhouse soil and also improved soil penetration resistance. The first year cultivation of maize increased the yield of garland chrysanthemum leaves but not the yield of green soybean. In first year, the yield of garland chrysanthemum showed negative correlation with SPAD value and nitrate content in leaves, while the yield of green soybean was positively correlated with shoot fresh weight and dry weights of roots and nodules. During the second year, cultivation of the catch crop clearly increased the yield of both garland chrysanthemum and green soybean. Positive correlations were observed between yield and SPAD value in garland chrysanthemum, and between yield and nodule dry weight in green soybean, respectively. These results indicate that using maize as a catch crop in soil with excessive N accumulation can improve soil conditions and promote subsequent crop growth. However, the effect of catch crop cultivation on yield was dependent on the type of subsequent crop.

Anthropogenic and Inherent Effects on Soil Organic Carbon across the U.S

Soil organic carbon (SOC) influences several soil functions, making it one of the most important soil health indicators. Its quantity is determined by anthropogenic and inherent factors that must be understood to improve SOC management and interpretation. Topsoil (≤15 cm) SOC response to tillage depth and intensity, cover crops, stover removal, manure addition, and various cropping systems was assessed using 7610 observations from eight U.S. regions. Overall, including cover crops, reducing tillage depth and intensity increased SOC. The positive effects of cover crops were more noticeable in South Central, Northwest, and Midwest regions. Removing high rates (&gt;65%) of crop residue decreased SOC in Midwestern and Southeastern soils. Depending on region, applying manure increased SOC by 21 to 41%, compared to non-manured soils. Diversified cropping systems (e.g., those utilizing small mixed vegetables, perennials, or dairy-based systems) had the highest topsoil SOC content, while more intensive annual row crops and large-scale single vegetable production systems, had the lowest. Among inherent factors, SOC increased as precipitation increased, but decreased as mean annual temperature increased. Texture influenced SOC, showing higher values in fine-texture than coarse-texture soils. Finally, this assessment confirmed that SOC can be a sensitive soil health indicator for evaluating conservation practices.

Simulating nitrate and DON leaching to optimize water and N management practices for greenhouse vegetable production systems

Nitrate and dissolved organic nitrogen (DON) leaching are major nitrogen (N) loss pathway for intensive greenhouse vegetable production system (GVPS). Quantifying the nitrate and DON leaching is essential to develop best management practices. In this study, four seasons of tomato field experiments were conducted to test the impact of different water (furrow and drip irrigation) and N management practices and straw incorporation on N leaching and vegetable yield. A soil-crop system model (WHCNS_Veg, soil Water Heat Carbon Nitrogen Simulator for vegetables) was calibrated and evaluated, and results suggested that the model performed well for simulating soil water potential, water drainage, nitrate and DON leaching, crop N uptake, and yield. The average values of NRMSE, IA, and NSE for nitrate (or DON) leaching ranged from 12.1 % (11.3 %), 0.96 (0.94), and 0.85 (0.77), respectively. Compared with furrow irrigation and over fertilization, drip fertigation treatments reduced irrigation water use, water drainage, nitrate and DON leaching by 41 %, 60 %, 68 %, and 68 %, respectively, without compromising crop yield. Straw incorporation further reduced nitrate and DON leaching by 13.1 % and 25.7 % compared with no straw incorporation. Furthermore, we found that DON leaching accounted for 21.7 %–46.6 % of total dissolved N leaching loss in the study area. Using the model, we determined that the optimal water and N inputs ranged from 350−400 mm and 350−400 kg N ha−1 for the winter-spring season and 200−250 mm and 150−200 kg N ha−1 for the autumn-winter season. This led to an 87 % reduction in nitrate leaching and a 74 % reduction in DON leaching with only a slightly reduction in crop yield (<5 %) compared with the local farmer practice. The recommended water and N management practices achieved high crop yield with less environmental impact.

Transição agroecológica em cooperativa de agricultores familiares de Itapuranga, Goiás

O presente trabalho buscou descrever os avanços, benefícios e dificuldades da transição agroecológica do sistema de produção de frutas e hortaliças em cooperativa de agricultores familiares de Itapuranga, Goiás, Brasil, bem como os custos de implantação do cultivo convencional e agroecológico e a rentabilidade auferida com a prática agroecológica. Para a realização dessa pesquisa, utilizou-se o delineamento de uma abordagem de pesquisa qualitativa exploratória. Como instrumento de coleta de dados foram utilizados questionários estruturados e entrevistas não estruturadas. De acordo com os resultados é perceptível a satisfação dos que trabalham com as práticas agroecológicas, os que investiram em mão de obra, bem como em assistência técnica. Os agricultores que possuíam mais de 15 hectares de terras concordam que suas receitas aumentaram embora tivessem dificuldades para dar continuidade aos projetos devido à ausência do apoio técnico após sua finalização. Durante a execução, a assistência técnica foi apontada como um problema devido à alta rotatividade de pessoal. Por fim, o sucesso dos agricultores que fizeram a transição do sistema de produção convencional vis-à-vis agroecológico resultou, sobretudo, em maiores ganhos econômicos, em parte, provenientes do recebimento de insumos e assistência técnica da cooperativa. Os produtores que possuíam mais recursos financeiros, mão de obra qualificada, consciência social e ambiental foram os que conseguiram maior agregação de valor ao produto final.

Humic Substances Improve Vegetable Seedling Quality and Post-Transplant Yield Performance under Stress Conditions

Vegetable growers require vigorous transplants in order to reduce the period of transplant shock during early stand establishment. Organic media containing solid humic substances (HS) are amendments that have not been comprehensively explored for applications in containerized vegetable transplant production systems. In this study, HS (1% v/v) were applied to a peat-based growth medium to evaluate pre- and post-transplant growth modulation of four economically important vegetable species. Those were: pepper, tomato, watermelon, and lettuce. Seeding for all species was performed in two periods in order to evaluate their post-transplant yield performance under drought (water deficit vs. well-watered) and heat (hot vs. cool season) stresses. Compared with control, HS-treated plants had: (1) increased leaf and root biomass after transplanting due to faster growth rates; (2) lower root/shoot ratio before transplanting, but higher after 10 days of field establishment; and (3) increased root length and surface area. The negative effects of heat and drought stresses on crop yield were more prominent in control plants, while HS-treated transplants were able to mitigate yield decreases. The results clearly demonstrated the benefits of using solid HS as a management input to improve transplant quality in these crop species.

Quantification of drudgery and ergonomics assessment of weeding activity in vegetable production system

Weeding activity in vegetable cultivation carried out by women is one of the drudgery prone activities. Women are regularly adopting poor and static posture while doing weeding for long hours by traditional equipment, resulting in various physical load on spine or lumbo-sacral region leads to drudgery coupled with work related musculoskeletal disorders (MSDs). The research paper aims to assess and quantify the drudgery with weeding activity by rural women in which physiological ergonomics evaluation was done for traditional method and with improved technological support with three replications of fifteen minutes work cycle without rest pause. Ergonomic parameters namely Heart Rate, Energy Expenditure Rate, Total Cardiac Cost of Work, Physiological Cost of Work, VO2 Max were measured during the experiments. Observations were recorded on farm women worker with normal health, without any major illness, regularly involved in farm operations and were in the age group of 25 to 45 years. Weeding activity of farm women was quantified and a sample of 10 physically fit rural women having permissible limit of physiological parameters were selected for the study. It was found from investigation that there was reduction in human physiological parameters, viz. heart rate, energy expenditure rate, Total Cardiac Cost of Work, Physiological Cost of work, Blood pressure and Oxygen Saturation.

Water-extractable fraction of vermicomposts enriched with Trichoderma enhances the growth of bell pepper and tomato as well as their tolerance against Meloidogyne incognita

Root-knot nematodes (RKN) are important pathogens on greenhouse-cultivated vegetables worldwide. The use of chemical inputs to cope with biotic stress is both more expensive and non-labor friendly. Therefore, effective control of RKN under tropical conditions is limited, but novel management methods comprising the use of microorganisms and soluble organic matter consist in promising alternatives. In the present study, water-extractable fraction of vermicomposts (WEFV) enriched or not with Trichoderma strains were evaluated for their efficiency in stimulating the growth and yield of bell pepper and tomato as well as their ability in increasing the tolerance of plants against Meloidogyne incognita. Treatments tested were: water-extractable fraction of a conventional vermicomposting process (V); water-extractable fraction of vermicompost enriched with Trichoderma asperellum (V + TA); water-extractable fraction of vermicompost enriched with Trichoderma virens (V + TV). A control treatment (water only) was also conducted for comparison. Bell pepper and tomato seedlings were inoculated with 5000 eggs and eventual second‐stage juveniles (J2) of Meloidogyne incognita race 1 and treated weekly with 200 ml of each vermicompost extract. Bell pepper plants treated with V + TV increased by 13 %, 29 %, and 56 % shoot dry mass, shoot height and root mass when compared to the control, respectively. A 10-fold increase in yield for tomato plants was observed when V + TV was applied when compared to the control. Regarding biocontrol of RKN, treatment V was able to reduce the number of eggs J2 in 62 % on bell pepper and 46 % on tomato plants when compared to the control. Treatment V also decreased RKN reproduction factor in 35 % for bell pepper and in 22 % for tomato plants, when compared to the control. The use of WEFV constitutes a potentially useful alternative to manage RKN and sustain plant growth in vegetable production systems.

Analysis of work profile in vegetable production system

Vegetable cultivation has become highly commercialized but still there is a wide gap between current production and potential productivity. The present study is an attempt to study the role of women in vegetable production system. Five villages from Dharwad taluka namely Yadawad, Lakmapur, Hebballi, Shivalli and Govinkoppa were selected for the study. The sample size comprised of 50 farm women from the selected villages. The study revealed that majority of the land preparation activities were performed by male gender. The planting/ sowing activities were performed by both male and female. Among weed management activities, spraying of weedicide was performed by only men. On the contrary, hand weeding was performed by only female. Harvesting activities were performed by both male and female gender. The transporting activities performed by male only. On an average the farm women spent 4 to 8 hours on agricultural activities. Majority of them were still following the traditional method and technologies. Hence, there is for introduction of improved/ mechanized agricultural technologies for the farming community to reduce the drudgery and save the labour cost.