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Cabbage is a popular vegetable grown in Kenya for food and income generation. Despite the important role played by the crop within the country, current climate change effects and population pressure pose a need for increasing production through utilization of available resources. A study was therefore conducted to evaluate the effects of black shade net on soil properties and cabbage water use efficiency in humid coastal environment. Black shade nets of 0%, 50% and 70% shading intensity and two cabbage types (Brassica rapa and Brassica oleracea) were evaluated in Randomized complete block design with three replications. 0% represented open field. Data collected included: soil chemical characteristics, soil moisture content, air temperature, fresh head weight, dry matter weight, and water use efficiency. Data obtained were subjected to analysis of variance using general linear model SAS Computer package version 9.1 and means separated using Tukey’s test at 5%. From the findings obtained, the use of black shade net of 70% and 50% shading significantly increased soil moisture content by 5.1% and 2.6% than open field. Maximum air temperature in 70% and 50% shade nets was lower than open field by 4.6⁰C and 1.8⁰C respectively while minimum air temperature under 70% and 50% shade nets was higher than open field by 2.7⁰C and 1.6⁰C respectively. Brassica rapa from 70% shading had 35% more fresh weight per plant than open field while those from 50% had 30%. Brassica oleracea from both 70% and 50% shading had 44% and 29% more fresh weight per plant respectively than those from open field. Although shade nets did not have significant effect on availability of nutrients within soil solution, Brassica rapa under 70% shading recorded 49% higher water use efficiency than open field while, 50% shading recorded 50% more WUE than open field. Brassica oleracea under 70% shading recorded 41% higher water use efficiency than open field, while 50% shading recorded 25% increase than open field. Owing to the fact that shade nets did not have significant effect on available nutrients within the soils but significantly influenced WUE, there is need for further studies to understand the effects of shade nets on cabbage nutrient use efficiency under the same environment.

Cabbage is an important vegetable to humans since it provides crucial nutrients such as fiber, minerals, and vitamins. They also help manage cancer, cardiovascular diseases, prevent type 2 diabetes, and inflammation of the digestive systems. However, its production in the tropics is constrained by climatic and edaphic factors that include soil moisture stress, high soil and air temperatures, high evapotranspiration, and unbalanced nutrition. Due to the above challenges, sustainable cabbage production requires adoption of technologies that can modify the growth environment with minimal environmental effects. A field study was conducted at Pwani University Crop Science farm, Kilifi County, to evaluate the effects of black shade net on yield of Brassica rapa and Brassica oleracea. A randomized complete block design experiment with three replications was set. The treatments included: 50%, 70% black shade net intensity and open field as control. Data collected included, leaf chlorophyll content, fresh head weight, and dry matter weight. The data obtained was subjected to analysis of variance using General Linear Model (GLM) SAS Computer package version 9.1. The results indicated that, shading resulted in decreased chlorophyll content, and that use of 50% and 70% black net shading intensity significantly resulted in 55% and 47.5%, more number of cabbage heads for Brassica rapa than open field respectively, while in Brassica oleracea, 70% shading and 50% resulted in 60% and 52% more cabbage heads than open field respectively.

Cabbages are important for income generation, human nutrition, and health promotion. Its production in the tropics is constrained by soil moisture stress and high temperatures. Sustainable production requires the adoption of technologies that modify growth environment. A study was conducted to evaluate the performance of Brassica rapa and Brassica oleracea under shade nets within coastal environments. Randomized complete block design, with three replications, was used. Treatments were: 0%, 50% and 70% shading, using black shade net. Data collected include plant height, stem diameter, crown diameter, leaf chlorophyll, number of open leaves and quality heads, and fresh head weight. Data obtained were subjected to ANOVA and means separated using Tukey’s test at 5%. 70%, and 50% shading significantly increased plant height than open field by 7.1cm and 5.3cm respectively. Number of open leaves and leaf chlorophyll content in both cabbages decreased with increase in shading intensity. Brassica rapa under 70% and 50% shading had 55% and 47.5% more yield than open field respectively, while Brassica oleracea under 70% and 50% shading had 62.5% and 53% more yield than open field respectively. Brassica rapa under 70% shading had 0.8 kg more fresh weight per plant than open field while 50% had 1 kg. Brassica oleracea had 1 kg more fresh weight per plant than open field in both 70% and 50% shading. Therefore, black shade net of 50% and 70% shading favoured cabbage production in a coastal environment and they can be used in areas with similar ecological conditions.

Purpose: The purpose of the study was to establish factors that influence vegetable commercialization among smallholder farmers of fresh vegetables in Kenya. The present study defined commercialization against farmer characteristics including portion of land committed to vegetable farming, share of household income generated from it, and the producers’ perception that the vegetables they consumed at the farm were produced or procured without any substantial cost. Methodology: The researcher adopted a cross-sectional survey design to randomly recruit a sample of crop farmers (n=118) from Kirinyaga and Kiambu counties in Kenya. Data on agrochemical use, crop diversity and scale as well as logistical issues regarding proximity to markets and social status of the crop farmers were collected using a researcher-administered questionnaire in a one-on-one interview. These data were initially entered on MS Excel spread sheets for cleaning and later transferred to Minitab (Ver 12) for statistical analyses. Principal component analysis (PCA) was used to isolate crucial commercialization factors responsible for varying agrochemical use behaviours among crop farmers and later presented in scree plots. Results/Findings: The study revealed that commercialization of tomatoes and kale was real in different areas of study which was influenced by structural and socio-demographic factors. From the study findings, structural policies to promote horticulture and high value crop production had a positive impact on production of vegetables while wildlife conservation and livestock development resulted to human-wildlife conflicts due to agrochemical abuse. Various socio-demographic factors that influence commercialization of vegetables included: household size, farm size, proportion of land used for vegetable production and household income. It emerged that household size (Eigen value EV=3.63), income (EV=2.61) and farm size (EV=1.27) accounted for 68.4% of variability in agrochemical abuse. This finding also explains their marginalization from county government extension services and high costs of market access. Unique contribution to theories, practice and policy: The study finds that vegetable farmers’ perception of commercialization leaned more towards increasing production in response to consumer demand and not necessarily to raise household food supplies. Famers dedicated over two thirds (66.67%) of their land to vegetable farming to support their livelihood (97.1%, SE= 1.30). Commercialization of vegetable farming was influenced by the level of education (SE=3.68). The study found out that that access to ICT equipment, particularly mobile phones, were the prime means via which farming techniques and agribusiness practices were learnt or improved (V= 0.196 Pearson, p=0.11).

Salinity is a major biotic factor that negatively affects growth and yield of crops. Over 90% of the coastal region of Kenya is arid and semi-arid, most farmers in the region use borehole irrigation water which is saline. Amaranthus spp. is one of the main vegetables grown in coastal region. There is limited information regarding the effect of salinity on amaranthus production. The study sought to determine the effect of saline irrigation water on amaranthus growth in coastal Kenya. Two experiments were set up, one at Mivumoni Secondary School farm in Kwale County and another at Pwani University farm in Kilifi County from beginning of September 2019 to the end of January, 2020. The experiments were laid out in a randomized complete block design and replicated three times. The six treatments tested were: fresh water alone, 75% saline water alone, 100% saline water alone, fresh water + DAP, 75% saline water + DAP, 100% saline water + DAP. Crop growth data collected were: emergence rate, plant height, leaf number, leaf area, chlorophyll content, stem thickness, root density, root weight, root volume and total plant biomass. Data obtained were subjected to analysis of variance using SAS statistical package (SAS, Version 10) and treatment effects were tested for significance using F-test. Significant means at F-test was ranked using Tukey’s test at 5% level of significance. Amaranthus seeds sown in fresh water had higher emergence rate compared to seeds sown in saline water. Salinity regardless of concentration used and application of DAP, resulted in decrease in height, leaf number, leaf area, stem tickness, chlorophyll content, root length, root weight, root volume and total biomass. The study demonstrates that saline irrigation water in coastal Kenya has a negative effect on Amaranthus growth.

The commercialization of fresh vegetables is crucial in enhancing revenues from commercial vegetable farming and ensuring reliable supply of high-quality produce for consumers. However, this is only guaranteed under ethical application of agrochemicals beyond which can lead in a more pronounced public health as well as environmental hazards. The present paper sought to examine the influence of commercialization on food safety. Vegetable samples weighing between 1 to 2 kg were purchased from randomly selected producers in two major producing counties (Kiambu and Kirinyaga) in Kenya. All samples were freeze-dried and stored in an ice chess box, to minimize contamination. Then the samples were labeled, and transported to the laboratory for processing and testing. All approved samples were subjected to the QuEChERS preparation method for pesticides and quantified using gas chromatography equipped with mass spectrometry (GC-MS). Lab results tested positive for 13 problematic pesticides including known carcinogens and highly hazardous agrochemicals such as Malathion, chlorothalonil and chlorpyrifos. The most common agrochemical was carbofuran (67%) in terms of insecticide. For the case of fungicides, the most common was mancozeb (60%) and metalaxyl (58%). Food safety issues are caused mainly by not observing preharvest intervals, excessive application of chemicals and use of illegal agrochemicals. Chemical residues in food mainly results in carcinogenic diseases (43 to 49%), stomach related problems (15 to 19%), eye related problems (10 to 15%), and skin related problems (11 to 14%) and breathing difficulties (10 to 12%). This study demonstrates that there is a problem of agrochemical use and food safety concerns and kale and tomato value chain.

Purpose: For many years the failure of actors such as farmers to comply with regulations that promote public good, such as adherence to safe practices in the use of agrochemicals was only understood from a position of weak enforcement and surveillance. The study sought to evaluate agribusiness regulatory compliance and consumers’ willingness to pay for a food safety premium among vegetable producers in Kenya. Methodology: The researcher adopted a cross-sectional survey design to randomly recruit a sample of crop farmers (n=118) and vegetable consumers (n=235) from Kirinyaga and Kiambu counties in Kenya, respectively. Data on consumer willingness to pay for safe agricultural produce as well as logistical issues regarding proximity to markets and social status of the crop farmers were collected using a researcher-administered questionnaire in a one-on-one interview. A similar approach was adopted to interview consumers’ social status and vegetable consumption patterns. Results/Findings: The study found that the present commercialization of tomatoes and kales is driven by low-income earners’ bid to earn a livelihood. However, their capital limitations push them to farm outside planned areas such as forests fringes, riverbanks or low potential zones in which they face extraordinary pressure from pests and diseases, which in turn compel them to abuse agrochemicals. This finding also explains their marginalization from county government extension services, high costs of market access and potential to experiment with classified agrochemicals. The study revealed that high income consumer from Westlands (91.44%) were likely to consider agrochemicals in their decisions to purchase vegetables compared to medium and low-income from Kasarani and Embakasi (2.21% and 6.35%), respectively. Majority of the vegetable consumers were not aware of varied agrichemical used by fathers as well as their health and environmental effects.There is reason to believe that both farmers and consumers could be heavily exposed to which the study proposes a population-based survey to assess agrochemical poisoning. Unique contribution to theories, practice and policy: This study finds compelling evidence to suggest that livelihood and farming outcomes of vegetable farmers are a key consideration among consumers purchase decisions. The findings also suggest that these factors significantly incentivize the farmer to comply with agribusiness ethics regulations. The paper recommends a training of extension officers and advocate for more budgetary allocation on agriculture. The extension officers will in turn train farmers on god farming practices as well as implementation of mitigation measures in relation to toxic pesticides. The researcher feels that there is a need to for a research to be conducted to understand the involvement of farmers in the formulation of policies and agribusiness practices rules in order to gain knowledge on the level of acceptance of these polices among farmers in Kenya. Key words: Consumers, Producers, Food-safety, Premium

Production of eggplant (Solanum melongena L.) is influenced by limited soil water and fertility conditions that affect its growth and yield. The use of superabsorbent polymer (SAP), also known as slush powder and rabbit manure are among the strategies that can improve soil conditions, hence growth and yield of crops. The objective of the study was to evaluate the effects of SAP and rabbit manure on soil moisture, growth and yield of eggplant. The study was conducted at Pwani University, Kilifi, Kenya. A randomized complete block design with three replications was used. The treatments were SAP, rabbit manure, SAP plus rabbit manure and control (without SAP or rabbit manure). Soil moisture, growth and yield parameters were determined. Superabsorbent polymer and/or rabbit manure improved soil moisture, growth and yield of eggplant compared with the control. Use of SAP had a better soil moisture retention, growth and yield comparable to SAP combined with rabbit manure. The finding demonstrates that use of SAP and/or rabbit manure may help in better soil water and nutrient management particularly in arid and semi-arid areas to improve growth and yield of eggplant.

African nightshade (Solanum scabrum Mill.) is important for its nutrition, health promoting compounds and its contribution in providing a secure food supply and livelihood for smallholder farmers in rural, peri-urban and urban areas in Kenya. However, inadequate postharvest handling practices result in high losses. To address this issue, studies were conducted to evaluate the effect of modified atmosphere packaging (MAP) on improving storability, nutritional and health promoting compounds of 'Olevolosi' African nightshade. Plants were cultivated in a climate chamber for four weeks and three weeks under greenhouse conditions. Leaves were harvested and either packaged in MAP (Xtend®) or left in the open (control). The leaves were stored for 8 days to simulate retail conditions (20°C and RH 56%) and 15 days in cold storage (7°C and RH 86%). Fresh weight loss, leaf colour, antioxidative compounds (i.e., β-carotene, lutein, lycopene, vitamin E, and vitamin C), chlorophylls, protein, microbial counts, and gas composition within MAP were evaluated. The results showed that leaf colour was retained by MAP, more so at 7°C. MAP reduced weight loss by 76.4-83.9% at 20°C and 71.0-84.8% at 7°C compared with the control. Moreover, MAP maintained or even increased the content of protein, vitamins C and E, β-carotene, lutein, lycopene and chlorophylls in both storage conditions in comparison to the control. During storage, the concentration of CO2 increased to 0.7-3.3%, while O2 was reduced by 0.9-3.3% being more pronounced at 20°C, compared to ambient conditions. However, the use of MAP did not reduce microbial counts. The findings indicate the potential of using MAP to improve shelf life and preserve bioactive quality compounds of African nightshade. This could be a vital step to improve nutrition, health and the economic status of smallholder farmers in developing countries such as Kenya.

Vegetable amaranth (Amaranthus cruentus L.) is gaining importance among the African indigenous leafy vegetables (AIVs) in the diets of many households in Africa. However, improper processing, handling, and storage of AIVs often result in faster deterioration thus high quantitative and qualitative losses with reduced availability of these highly nutritive and health promoting plants. Targeted application of UV-C has been shown to induce beneficial physiological responses of crops after harvest. The present study was conducted to evaluate the effects of postharvest UV-C application on health promoting secondary plant compounds of vegetable amaranth cv. Madiira. Eight weeks after planting, leaves were harvested and treated with UV-C (254 nm) at either 1.7 kJ m−2 or 3.4 kJ m−2 while untreated leaves served as control. The leaves were kept up to 4 d and 14 d at 20 °C (65% RH) and 5 °C (85% RH), respectively. Characteristic health promoting plant compounds, such as vitamin E, carotenoids, flavonoids, phenolic acids, as well as glutathione peroxidase (GPOX) activity and antioxidant capacity (TEAC) and their correlations were analyzed. Results showed that the accumulation of secondary metabolites was dependent on UV-C dosage, storage temperature and duration. Vitamin E, carotenoids (e.g. lycopene, β-carotene and lutein), flavonoids (e.g. quercetin and kaempferol derivatives), phenolic acids (e.g. ferulic, coumaric and caffeic acid derivatives) as well as GPOX activity and TEAC increased in UV-C treated vegetable amaranth leaves compared with the untreated samples. Furthermore, there was a relationship in most studied secondary compounds and TEAC. The UV-C effects at both storage conditions were comparable for most studied compounds while storage duration variedly affected the compounds studied. The increase in the studied secondary plant compounds is attributed to their plant defense mechanism against oxidative damage of plant tissues by UV-C irradiation. This could be an important strategy in reducing the loss of secondary plant compounds, hence maintaining nutritional and health promoting properties of AIVs during postharvest supply chain.

Due to high perishability, African indigenous leafy vegetables (AIVs) tend to suffer heavy postharvest loss. There is a lack of information regarding management of loss of these vegetables. This st...

Over the last decade, African indigenous leafy vegetables (AIVs) such as African nightshade ( Solanum scabrum Mill.) have featured increasingly in both formal and informal markets in the peri-urban and urban centres of Africa, due to the increasing awareness of their nutritive and medicinal as well as expanding economic value. AIVs are rich in nutritional and health promoting plant compounds such as vitamins, minerals, proteins, dietary fibre and antioxidant compounds. However, the crop is highly perishable and more than half of it is lost before it reaches the consumer. In Kenya, appropriate postharvest handling and treatments, storage or refrigeration facilities are lacking. More so, the information on postharvest losses of the AIVs is limited, making the management of such losses along the supply chain very difficult. The objective of the study was to determine nutritional and economic losses of African nightshade plants along the supply chain, i.e. from producer until marketing. The study was conducted in the three main commercial AIVs producing counties in Kenya, i.e. Nakuru, Kisii and Kakamega, where three farmers from each county were randomly selected. The farmers were allowed to carry out their normal routine AIVs handling procedure right from harvesting to selling; and samples were collected at each supply chain stage (at harvest, before transport, after transport and at the market). Dry matter, selected macro-nutrients (N, P, K, Ca and Mg) and micro-nutrients (Fe and Zn), protein, carotenoids and chlorophyll content, cumulative produce and economic losses as well as the causes of losses were evaluated. The results obtained revealed significant quantitative, nutritive, and economic losses of African nightshade along the supply chain. The dry matter content was reduced by between 32.8–45.5%, depending on the county, along the supply chain. The mineral elements and protein were reduced by between 3.2–29.4%, while chlorophylls and carotenoids were reduced by between 70.9–90.9% and 70.4–91.9%, respectively. Cumulative produce loss was between 71.8–292.4% while the economic loss was between 12.6–34.4%. The findings indicate the immense losses of nutritional, quantitative and economic values of African nightshade along the supply chain. Lack of certified seed varieties, unfavourable weather, inadequate postharvest handling practices and technologies as well as insect pest and diseases are the main causes of losses during the supply chain. Therefore, maintaining quality attributes and managing postharvest losses in AIVs could be among the key issues to improving food security in developing countries.

Currently, consumer eating habits have shifted to an increasing demand for high quality, safe and healthy food products worldwide. In many African countries, specifically African indigenous leafy vegetables (AIVs) gained importance in this respect contributing to human diet by providing minerals, proteins, vitamins and health-promoting antioxidant compounds. Moreover, these vegetables have an immense potential in creating job opportunities in rural as well as peri-urban areas. However, AIVs tend to suffer severe quantitative and qualitative postharvest losses because of their high perishability. UV-C has been mainly applied in sanitation and food safety for its germicidal effect but also has an impact on preventing nutritional losses. To address this, studies were conducted to evaluate the effect of postharvest application of hormic UV-C dosages on bioactive plant compounds of two AIVs, i.e. African nightshade (Solanum scabrum Mill.) cv. Olevolosi and vegetable amaranth (Amaranthus cruentus L.) cv. Madiira. Eight weeks after planting, the leaves were harvested and treated with UV-C (254 nm) at either 1.7 kJ m−2 or 3.4 kJ m−2 while untreated leaves served as control. The leaves were kept for 4 and 14 d at 20 °C (65% RH) and 5 °C (85% RH), respectively. The quality parameters studied were fresh weight loss, mineral elements (N, P, K, Ca, Mg, Fe, and Zn), protein, and structural carbohydrates determining dietary fibre content and microbial counts. In addition, antioxidative, health promoting plant compounds, i.e. carotenoid, and chlorophyll contents were evaluated. The results showed that fresh weight loss of both AIVs was significantly reduced with application of lower UV-C dosage (1.7 kJ m−2). Mineral elements and proteins were variedly affected with a general decline in the initial stages followed by an increase compared to the untreated leaves. Hemicellulose and cellulose was significantly increased in vegetable amaranth and lignin content was significantly increased in African nightshade following UV-C treatment. Chlorophyll and carotenoid contents declined within 2–4 d during storage, depending on storage conditions; but thereafter increased again significantly compared to the control. Aerobic mesophyllic and yeast counts were significantly reduced by UV-C treatment, while mould counts were not affected. The findings demonstrate the potential of using hormic UV-C for maintaining the nutritional quality of AIVs during their supply chain as an easy to apply and effective tool, hence contributing to improved food accessibility and food safety in Sub-Saharan areas such as Kenya.

French bean [Phaseolus vulgaris (L.)] is among the leading export vegetable in Africa, mostly produced by small-scale farmers. Unfavorable environmental conditions and heavy infestations by insect pests are among the major constraints limiting production of the crop. Most French bean producers grow their crop in open fields outdoors subject to harsh environmental conditions and repeatedly spray insecticides in a bid to realize high yield. This has led to rejection of some of the produce at the export market as a result of stringent limits on maximum residue levels. Two trials were conducted at the Horticulture Research and Teaching Field, Egerton University, Kenya, to evaluate the potential of using agricultural nets (herein referred to as agronets) to improve the microclimate, reduce pest infestation, and increase the yield and quality of French bean. A randomized complete block design with five replications was used. French bean seeds were direct-seeded, sprayed with an alpha-cypermethrin-based insecticide (control), covered with a treated agronet (0.9 mm × 0.7 mm average pore size made of 100 denier yarn knitted into a mesh impregnated with alpha-cypermethrin), or covered with an untreated-agronet (0.9 mm × 0.7 mm average pore size made of 100 denier yarn knitted into a mesh not impregnated with insecticide). Alpha-cypermethrin and agronets were manufactured by Tagros Chemicals (India) and A to Z Textile Mills (Tanzania), respectively. Covering French bean with the agronets modified the microclimate of the growing crop with air temperature increased by ≈10%, relative humidity by 4%, and soil moisture by 20%, whereas photosynthetic active radiation (PAR) and daily light integral (DLI) were decreased by ≈1% and 11.5%, respectively. Populations of silverleaf whitefly [Bemisia tabaci (Gennadius)] and black bean aphids [Aphis fabae (Scopoli)] were reduced under agronet covers as contrasted with control plots. Furthermore, populations of both pests were reduced on French bean grown under impregnated agronets compared with untreated agronets, but only on three of the five sampling dates [30, 44, and 72 days after planting (DAP)] for silver leaf whitefly or at only one of the five sampling dates (30 DAP) for black bean aphid. Covering French bean with agronets advanced seedling emergence by 2 days and increased seedling emergence over 90% compared with control plots. French bean plants covered with both agronet treatments had faster development, better pod yield, and quality compared with the uncovered plants. These findings demonstrate the potential of agronets in improving French bean performance while minimizing the number of insecticide sprays within the crop cycle, which could lead to less rejection of produce in the export market and improved environmental quality.

For >20 yr, Bemisia tabaci Gennadius persists as a begomovirus vector and is a serious problem in tomato production in many parts of the world. In tropical countries, the use of netting to protect horticultural crops has proven to be an effective and sustainable tool against Lepidoptera but not against small insects. This study evaluated the repellent effect of AgroNet 0.9T, a 0.9-mm pore diameter and 40-mesh size netting treated with alphacypermethrin insecticide against B. tabaci. This pyrethroid insecticide is known to have toxic and repellent effects against mosquitoes and has been used for treatment of mosquito nets. Two nontreated netting materials were used as control: AgroNet 0.9NT with 0.9-mm pore diameter and 40-mesh size and AgroNet 0.4NT with 0.4-mm pore diameter and 80-mesh size. The behavior of B. tabaci and its parasitoid Encarsia formosa Gahan as they progressed through the treated netting was studied in the laboratory in choice and no-choice tests. The development of wild B. taba...

Tomato (Lycopersicon esculentum) is one of the important vegetables in supplying vitamins, min- erals and fiber to human diets worldwide. Its successful production in the tropics is, however, constrained by environmental variations espe- cially under open field conditions. Two trials were conducted at the Horticulture Research and Teaching Field, Egerton University, Kenya to evaluate the effects of agricultural nets (ag- ronets) herein called eco-friendly nets (EFNs) and floating row covers (FRCs) on microclimate modification, yield, and quality of tomato. A ran- domized complete block design with five repli- cations was used. Tomato plants were grown under fine mesh EFN (0.4-mm pore diameter) cover, large mesh EFN (0.9-mm pore diameter) cover or FRC. The EFN and FRC were main- tained either permanently closed or opened thrice a week from 9 am to 3 pm. Two open con- trol treatments were used: unsprayed (untreated control) or sprayed with chemicals (treated con- trol). The use of EFN or FRC modified the micro- climate with higher temperatures, lower diurnal temperature ranges, and higher volumetric wa- ter content recorded compared with the controls. On the other hand, light quantity and photo- synthetic active radiation were reduced by the use of EFN and FRC compared with the controls. The use of FRC and EFN resulted in more fruit and higher percent in marketable yield com- pared with open field production. Fruit quality at harvest was also significantly improved by the use of EFN and FRC. Fruits with higher total soluble solids (TSS), lower titratable acidity (TA), and higher sugar acid ratio were obtained in EFN and FRC treatments compared with the controls. Fruits harvested from EFN and FRC were also firmer compared with control fruits. These find- ings demonstrate the potential of EFN and FRC in modifying microclimate conditions and im- proving yields and quality of tomato under tropi- cal field conditions.

Unfavorable environmental conditions, pests, and viral diseases are among the major factors that contribute to poor growth and quality of tomato (Solanum lycopersicum) seedlings in tropical areas. Improving crop microclimate and excluding insects that transmit viruses may improve transplant quality and yield in production fields. This study was carried out in two seasons at the Horticulture Research and Teaching Field of Egerton University in Njoro, Kenya, to investigate the effects of agricultural nets herein called eco-friendly nets (EFNs) on germination and performance of tomato seedlings. Tomato seeds were either raised in the open or under a permanent fine mesh net (0.4-mm pore diameter). Eco-friendly net covers modified the microclimate resulting in significantly higher day temperatures and relative humidity, compared with the open treatment. Nets increased temperature and relative humidity by 14.8% and 10.4%, respectively. Starting seeds under a net advanced seedling emergence by 2 days and resulted in higher emergence percentage, thicker stem diameter, more leaves, and faster growth leading to early maturity of seedlings and readiness for transplanting. Netting improved root development by increasing root quantity and length. Stomatal conductance (gS) and estimates of chlorophyll content were higher in seedlings under net covering compared with those in the noncovered control treatment. Insect pests and diseases were also reduced under net covering. The use of the net in the production of tomato transplants presented a 36.5% reduction in the cost of seeds, through improved emergence and reduced pest damage. All other factors held constant, healthy and quality transplants obtained under a net covering also translate into better field performance; hence, increasing economic returns for commercial transplants growers, as well as for tomato farmers. Results of this study suggest that EFNs can be customized not only for their effective improvement on growth and quality of tomato transplants but also for their pest and disease management in the nursery alone or as a component of integrated pest and disease management.

Tomato (Solanum lycopersicum L.) is an important vegetable for supplying vitamins, minerals and fiber in human diets worldwide. Successful open field production of tomato in the tropics is limited by insect pests among other constraints. Two trials were conducted at the Horticulture Research and Teaching Field, Egerton University, Kenya with the objective of evaluating the effects of agricultural nets (agronets) herein called eco-friendly nets (EFNs) and floating row covers (FRCs) on pest population and yield of tomatoes. A randomized complete block design with five replications was used. Tomato plants were protected with either fine mesh EFN (0.4-mm pore diameter), large mesh EFN (0.9-mm pore diameter) or FRC. The EFN and FRC were maintained permanently closed or opened thrice a week from 9 am to 3 pm. Two control treatments were used: open unsprayed (untreated control) or open and sprayed with alpha-cypermethrin based insecticide (treated control). The use of EFN and FRC helped to manage pests with the lowest pest population obtained under FRC maintained permanently covered and the highest population recorded in the untreated control. Covering tomato plants with EFN or FRC also resulted in more marketable fruit and lower yield losses compared with the unprotected systems. The EFN and FRC offer great potential as part of integrated systems for pest management and yield improvement in tomato production in regions with a tropical climate.