Maize-based Systems Research Articles

Pigeon pea: A companion crop for boosting maize growth and striga control in push-pull farming systems in Western Kenya

Crop diversification is one of the strategies for sustainable intensification that hold promise for reducing poverty and ending hunger in communities that derive livelihood from farming. Intensification of smallholder systems require identification of companion crops that are amenable to intercropping within existing crop and farming systems, add economic/marketable value, are a source of food, and provide ecosystem services not currently provided in existing crop or farming systems. Push-pull is a companion cropping system that involves intercropping cereal crops with forage legumes in the (e.g. Desmodium), and planting a forage grass (e.g. Brachiaria) around this intercrop to control stem borer, suppress witch weed (striga) in maize-based systems. This study evaluated the performance of push-pull system when further intensified with Cajanas cajan (pigeon pea). Four treatments were set up on farmers’ plots in Kisumu, Siaya and Vihiga counties during the long and short rain seasons in 2021, 2022 and 2023: (1) conventional push-pull, (2) push-pull with (pigeon pea), (3) maize and pigeon pea, and (4) maize mono-crop. Crop growth and striga weed density were monitored in 20×10 m plots demarcated in each treatment during the growing season. Data on maize growth, number and vigour of striga weed were recorded on all plants within sub-plots measuring 2x2 m for four seasons. Results show that integration with pigeon pea further suppresses striga weed and does not affect growth and yield of maize. Pigeon pea could be a potential alternative crop for weed management in smallholder farming systems, where it can serve as a source of firewood and fodder.

Integration of Grain Legumes and Mbeya Manure Improves Maize Productivity on Smallholder Farms in Central Malawi

Legumes are integrated in maize-based systems to improve soil fertility and crop productivity. However, the ecosystem services from legumes vary. Crop rotation on-farm studies were conducted over two cropping seasons (2018/19 and 2019/20) in Mkanakhoti and Kaluluma Extension Planning Areas (EPAs) in Kasungu district, central Malawi. The main objective of this study was to evaluate maize response to legume cropping systems and mbeya manure. In the first season (2018/19), five treatments including sole groundnut (Gn), sole soybean (soy), sole pigeon pea (PP), and doubled-up legumes (legume + legume intercrop) - pigeon pea intercropped with groundnut (Gn+PP), and pigeon pea intercropped with soybean (Soy+PP) were grown. In the second season (2019/20), maize was planted on plots that had either sole or doubled-up legumes. These plots were split into two, one half was top dressed with 23kg N ha-1 only and the other half received 23kg N ha-1+1000kg ha-1 mbeya manure. The experiments were replicated in 2019/2020 and 2020/2021 seasons. Soil fertility was low and highly variable between farms in the study sites. Soil pH, total nitrogen (N), available phosphorus (P), organic matter (SOM) and active carbon in topsoil (0-15cm) averaged 5.1±0.5, 0.19±0.18%, 31±19.6 ppm, 1.4±0.34 %, and 193±74 mg kg-1, respectively. Application of mbeya manure to maize increased leaf chlorophyll and plant height (p<0.05). There were variations in maize yield responses to legumes with higher benefits obtained from maize rotated with doubled-up legumes than sole legumes. The results also showed that on non-responsive soils, overall, the use of mbeya manure in combination with legume systems increased the rotational maize grain yield by 88% over maize following legumes only (p<0.05), with highest yields from doubled up legumes/maize rotations followed by groundnut/maize rotations. It is therefore recommended that on highly degraded soils, farmers can increase maize productivity through integrated soil fertility management involving a combination of 23kg N/ha and 1000kg/ha of mbeya manure applied to maize rotated with doubled-up legumes (Gn+PP or Soy+PP) and sole groundnut (Gn). Key words: Doubled-up legumes, crop rotation, groundnut, pigeon pea, soybean, maize, mbeya manure

Bibliometric Trends and Insights into the Potential of Maize (Zea mays) under the Framework of Conservation Agriculture

In spite of the detrimental effects of climate change and decreasing resource efficiency, maize farming is essential to the world’s food and nutritional security. With regard to sustainable maize farming in this environment, conservation agriculture (CA) offers a framework that holds promise in terms of low soil disturbance, perennial soil cover, and sustainable crop rotation. In order to acquire more profound information on the research advancements and publication patterns related to maize under CA scenarios, a bibliometric analysis was conducted. This involved utilizing René Descartes’s Discourse Framework to extract and screen 2587 documents spanning the years 2001 to 2023 from the Dimensions.ai database. The mapping showed that different stakeholders were becoming more interested in maize research under various CA pathways, with a greater emphasis on reaching the second sustainable development target, or “zero hunger”. The most influential journals were “Soil and Tillage Research” and “Field Crops Research”, with 131 and 85 papers with 6861 and 6186 citations, respectively. The performance analysis found “Christian L. Thierfelder” and “Mangi Lal Jat” as the eminent researchers in the areas of maize research under CA. Thus, the International Maize and Wheat Improvement Center (CIMMYT) and the Indian Agricultural Research Institute (IARI) were identified as the important institutions in conducting research pertaining to maize under CA systems, while the United States, India, and Mexico emerged as prominent countries with notable collaboration efforts for imparting research under the given scenarios. Three thematic clusters delineating keywords from three distinct sections—key drivers, objectives, and methodology—were identified through co-word analysis using word clouds, tree maps, and thematic networking of the keywords from the abstract and titles of screened publications. These thematic clusters highlighted the growing emphasis on region-specific studies under CA, particularly in sub-Saharan Africa and the Indo-Gangetic plain, to enhance the resilience of the agri-food system. Therefore, mapping maize’s potentialities within the CA framework has revealed the field’s dynamic nature and offers insightful information to researchers and policymakers that could help them plan future studies and cooperative initiatives aimed at boosting the productivity and sustainability of maize-based systems under the CA framework.

Soil phosphorus fractionations as affected by cropping systems in the central mid-hills region of Nepal.

Soil plays a critical role as the primary reservoir of phosphorus (P) in terrestrial ecosystems. Sequential fractionation has been extensively utilized to gain insights into the characteristics and dynamics of soil P. However, there is a knowledge gap regarding the different P pools in Nepalese soils. Therefore, this study aimed to investigate the impact of cropping systems on soil P fractions in the central mid-hills of Nepal. The study focused on four cropping systems: vegetable, fruit, rice, and maize-based systems, which exhibited variations in nutrient management, topography, and cropping intensity. A total of 240 soil samples (60 samples from each cropping system) were collected from multiple sites within the central mid-hill region. Standard analytical methods were used to determine the general parameters of the soils, while the sequential fractionation method was employed to assess the organic and inorganic P pools. The results indicated that the effect of cropping systems on soil pH, calcium carbonate (CaCO3) content, and the proportion of sand, silt, and clay was not statistically significant in terms of general parameters. However, significant differences were observed among the different cropping systems in organic matter (OM), electrical conductivity (EC), cation exchange capacity (CEC), and available phosphorus. Similarly, in terms of inorganic phosphorus fractions, loosely bound P (LB-P), aluminum bound P (Al-P), iron bound P (Fe-P), and reductant soluble P (RS-P) were significantly affected, while calcium bound P (Ca-P) did not show a significant difference. Furthermore, in terms of organic phosphorus fractions, labile organic P (L-Po), fluvic acid organic P (FA-Po), and non-labile organic P (NL-Po) exhibited significant differences, whereas moderately labile organic P (ML-Po) and humic acid organic P (HA-Po) did not show a significant difference. Additionally, reductant soluble P showed a significant difference, while total P did not differ significantly. The vegetable-based system exhibited higher levels of the majority of P fractions, followed by the fruit-based, maize-based, and rice-based systems. These findings emphasize the importance of considering cropping systems and their response to different phosphorus pools, as this knowledge can contribute to the development of improved soil phosphorus management strategies and promote sustainable agricultural practices in the region.

A comprehensive analysis of resource conservation strategies: Impacts on productivity, energetics, and environmental footprints in rice-based systems of the Eastern Indo-Gangetic Plains

A comprehensive analysis of resource conservation strategies: Impacts on productivity, energetics, and environmental footprints in rice-based systems of the Eastern Indo-Gangetic Plains

Alternatives to maize monocropping in Mediterranean irrigated conditions to reduce greenhouse gas emissions

Alternatives to maize monocropping in Mediterranean irrigated conditions to reduce greenhouse gas emissions

Agronomic strategies to enhance the early vigor and yield of maize. Part I: the role of seed applied biostimulant, hybrid and starter fertilization on rhizosphere bacteria profile and diversity.

The sustainable intensification of maize-based systems may reduce greenhouse-gas emissions and the excessive use of non-renewable inputs. Considering the key role that the microbiological fertility has on crop growth and resilience, it is worth of interest studying the role of cropping system on the rhizosphere bacterial communities, that affect soil health and biological soil fertility. In this work we monitored and characterized the diversity and composition of native rhizosphere bacterial communities during the early growth phases of two maize genotypes of different early vigor, using a nitrogen (N)-phosphorus (P) starter fertilization and a biostimulant seed treatment, in a growth chamber experiment, by polymerase chain reaction-denaturing gradient gel electrophoresis of partial 16S rRNA gene and amplicon sequencing. Cluster analyses showed that the biostimulant treatment affected the rhizosphere bacterial microbiota of the ordinary hybrid more than that of the early vigor, both at plant emergence and at the 5-leaf stage. Moreover, the diversity indices calculated from the community profiles, revealed significant effects of NP fertilization on richness and the estimated effective number of species (H2) in both maize genotypes, while the biostimulant had a positive effect on plant growth promoting community of the ordinary hybrid, both at the plant emergence and at the fifth leaf stage. Our data showed that maize genotype was the major factor shaping rhizosphere bacterial community composition suggesting that the root system of the two maize hybrids recruited a different microbiota. Moreover, for the first time, we identified at the species and genus level the predominant native bacteria associated with two maize hybrids differing for vigor. These results pave the way for further studies to be performed on the effects of cropping system and specific crop practices, considering also the application of biostimulants, on beneficial rhizosphere microorganisms.

Intensified cropping reduces soil erosion and improves rainfall partitioning and soil properties in the marginal land of the Indian Himalayas

Intensified cropping reduces soil erosion and improves rainfall partitioning and soil properties in the marginal land of the Indian Himalayas

Adoption and impacts of improved post-harvest technologies on food security and welfare of maize-farming households in Tanzania: a comparative assessment

During the last decade, post-harvest losses (PHL) reduction has been topping the agenda of governments as a pathway for addressing food security, poverty, and nutrition challenges in Africa. Using survey data from 579 households, we investigated the factors that affect farmers’ decisions to adopt post-harvest technologies: mechanized shelling, drying tarpaulins, and airtight storage validated for reducing PHL in Tanzania’s maize-based systems, and the impacts on households’ food security and welfare. Mechanized shelling addressed a labor issue, while tarpaulins and airtight storage addressed product quality and quantity concerns. The results revealed large farm sizes and location in higher production potential zones (proxies for higher production scale) and neighbors' use of the technologies as universal drivers for adoption. Access to credit and off-farm income were unique determinants for airtight storage, while group membership increased the probability of adopting drying tarpaulin and airtight storage. The technologies have positive impacts on food security and welfare: drying tarpaulins and airtight storage significantly increased food availability (18–27%), food access (24–26%), and household incomes (112–155%), whereas mechanized shelling improved food and total expenditures by 49% and 68%, respectively. The share of total household expenditure on food decreased by 42%, 11%, and 51% among tarpaulin, mechanized shelling, and airtight storage adopter households, signaling significant improvements in food security and reductions in vulnerability. The results point to the need for policy support to enhance the adoption of these technologies, knowledge sharing among farmers, and financial resources access to support investments in the technologies.

Evaluating net energy and protein feed conversion efficiency for dairy ruminant systems in France

Modern systems of animal production are facing increasing challenges on issues such as animal welfare, product quality, and environmental impact. Ruminants in particular are often regarded as being inefficient with respect to feed conversion for both protein and energy. Efficiency is defined as the ratio between resources and production; when applied to dairy production systems, it corresponds to the total amount of feed (kg of dry matter of roughages and concentrates) consumed per kg of milk and meat produced. This ratio underlines the biological ability of dairy cows, ewes, and goats to convert feed into products that are edible by humans while maintaining other physiological functions. Feeds consumed by animals can be “human-edible”, i.e. directly usable for human nutrition (cereals, legumes, maize silage), or not (grasslands, wild grass areas). Calculations of livestock efficiency are strongly influenced by whether or not they consider, and distinguish between, the consumption of human-edible or -inedible plant resources (roughages and concentrates) as well as the production of edible and/or inedible animal products (e.g., milk, meat, wool, leather). An improved understanding of the inedible fraction of both energy and protein in animal feed will be invaluable in analyses of feed-food competition, especially in ruminants. In this study, we investigated the feed conversion efficiency (FCE) of dairy ruminant systems in France (cow, goat, ewe) with respect to both energy and protein. We hypothesized that FCE would be influenced by the composition of the diet and its grass content, as well as, by animal type. Data from a French database (Diapason) provided information on land, labor, herds, and production from 2012 to 2016 for 274 dairy goat farms, 108 dairy ewe farms, and 498 dairy cow farms. These herds consumed feeds that were human-edible (cereals, legumes, maize silage) as well as -inedible (grasslands, wild grass areas). We estimated that French dairy systems are, on average, net consumers of energy and net producers of protein, with higher efficiencies for grass-based systems compared to maize-based systems. At the national scale, average net protein efficiencies were 1.16, 1.12, and 1.88 for ewes, goats, and cows, respectively. These results on the net FCE in dairy systems will promote a more objective quantification of their contribution to food security, which should be taken into account in assessments of feed-food competition and its impact on human nutrition. When combined with other factors such as greenhouse gas emissions and land and resource use, such considerations will help to inform discussions of the future of livestock production.

Cropland intensification mediates the radiative balance of greenhouse gas emissions and soil carbon sequestration in maize systems of sub-Saharan Africa.

Sub-Saharan Africa (SSA) must undertake proper cropland intensification for higher crop yields while minimizing climate impacts. Unfortunately, no studies have simultaneously quantified greenhouse gas (GHG; CO2 , CH4 , and N2 O) emissions and soil organic carbon (SOC) change in SSA croplands, leaving it a blind spot in the accounting of global warming potential (GWP). Here, based on 2-year field monitoring of soil emissions of CO2 , CH4 , and N2 O, as well as SOC changes in two contrasting soil types (sandy vs. clayey), we provided the first, full accounting of GWP for maize systems in response to cropland intensifications (increasing nitrogen rates and in combination with crop residue return) in SSA. To corroborate our field observations on SOC change (i.e., 2-year, a short duration), we implemented a process-oriented model parameterized with field data to simulate SOC dynamic over time. We further tested the generality of our findings by including a literature synthesis of SOC change across maize-based systems in SSA. We found that nitrogen application reduced SOC loss, likely through increased biomass yield and consequently belowground carbon allocation. Residue return switched the direction of SOC change from loss to gain; such a benefit (SOC sequestration) was not compromised by CH4 emissions (negligible) nor outweighed by the amplified N2 O emissions, and contributed to negative net GWP. Overall, we show encouraging results that, combining residue and fertilizer-nitrogen input allowed for sequestering 82-284 kg of CO2 -eq per Mg of maize grain produced across two soils. All analyses pointed to an advantage of sandy over clayey soils in achieving higher SOC sequestration targets, and thus call for a re-evaluation on the potential of sandy soils in SOC sequestration across SSA croplands. Our findings carry important implications for developing viable intensification practices for SSA croplands in mitigating climate change while securing food production.

Land-use systems regulate carbon geochemistry in the temperate Himalayas, India

Land-use systems regulate carbon geochemistry in the temperate Himalayas, India

Evaluating Climate-Smart Agriculture as Route to Building Climate Resilience in African Food Systems

Efforts to meet the growing demand for food across Africa have led to unsustainable land management practices that weaken the resilience of African Food Systems. Soil health is key to building more climate-resilient agricultural systems and can be improved through Climate-Smart Agriculture (CSA) practices that also enhance soil carbon storage. Many CSA practices are being implemented by African farmers, whereas others are being actively promoted but adoption remains low due to multiple factors including weak policy integration, limited institutional support, and inadequate agricultural extension advice. This Short Communications paper presents overview findings from trans-disciplinary research projects from Southern, East, and West Africa to evaluate the potential importance of integrated participatory soil health studies designed to inform context-specific recommendations and policies for resilient African food systems. The use of soil health indicators to measure the effectiveness of implemented CSA practices including Conservation Agriculture in maize-based systems and Soil and Water Conservation in Highland African systems are discussed. The paper identifies how more integrated research can help to enable shared learning and the enhanced knowledge exchange required for the upscaling of sustainable land management practices enabled through enhanced farmer participation in the chain of CSA activities from intervention design to community evaluation of impacts.

Simulating soil organic carbon in maize-based systems under improved agronomic management in Western Kenya

Improved management practices should be implemented in croplands in sub-Saharan Africa to enhance soil organic carbon (SOC) storage and/or reduce losses associated with land-use change, thereby addressing the challenge of ongoing soil degradation. DayCent, a process-based biogeochemical model, provides a useful tool for evaluating which management practices are most effective for SOC sequestration. Here, we used the DayCent model to simulate SOC using experimental data from two long-term field sites in western Kenya comprising of two widely promoted sustainable agricultural management practices: integrated nutrient management (i.e. mineral fertilizer and crop residues/farmyard manure incorporation) and conservation agriculture (i.e. minimum tillage and crop residue retention). At both sites, correlations between measured and simulated SOC were low to moderate (R2 of 0.25−0.55), and in most cases, the model produced fairly accurate prediction of the SOC trends with a low relative root mean squared error (RRMSE < 7%). Consistent with field measurements, simulated SOC declined under all improved management practices. The model projected annual SOC loss rates of between 0.32 to 0.35 Mg C ha-1 yr-1 in continuously tilled maize (Zea mays) systems without fertilizer or organic matter application over the period 2003–2050. The most effective practices in reducing the losses were the combined application of 4 Mg ha-1 of farmyard manure and 2 Mg ha-1 of maize residue retention (reducing losses up to 0.22 Mg C ha-1 yr-1), minimum tillage in combination with maize residue retention (0.21 Mg C ha-1 yr-1), and rotation of maize with soybean (Glycine max) under minimum tillage (0.17 Mg C ha-1 yr-1). Model results suggest that response of the passive SOC pool to the different management practices is a key driver of the long-term SOC trends at the two study sites. This study demonstrates the strength of the DayCent model in simulating SOC in maize systems under different agronomic management practices that are typical for western Kenya.

Improved nutrition and resilience will make conservation agriculture more attractive for Zambian smallholder farmers

AbstractFood and nutrition insecurity in southern Africa call for improvements in traditional agriculture systems. Conservation Agriculture (CA) based on minimum soil disturbance, permanent soil cover and crop diversification has been implemented as a strategy to maintain yields while safeguarding the environment. However, less focus has been placed on potential synergistic benefits on nutrition security. Maize-based systems may increase household income through selling but may not lead to proportionate reduction in malnutrition. Crop diversification in CA systems can have a direct impact on the nutritional status of farm households due to improved dietary diversity. Here we assess how the integration of grain legumes, cowpeas and soybeans, in maize-based CA systems either as intercrops or rotational crops affects maize grain yield and stability, total energy yield, protein yield and surplus calories after satisfying the daily requirement per household. The experiments were carried out from 2012 to 2020 (nine consecutive cropping seasons) in six eastern Zambian on-farm communities using 966 observations. Results show that intercropping compromises maize yields with marginal yield penalties of −5% compared to no-till monocropping. However, intercropped yields were more stable across environments. Total system caloric energy and protein yield were highest in intercropping systems due to higher productivity per unit land area owing to the additive contribution of both maize and legumes. Total system caloric energy and protein yield reached yearly averages of 60 GJ ha−1 and 517 kg ha−1, respectively, for the intercropping system as compared to 48 GJ ha−1 and 263 kg ha−1 in monocropped maize systems. Tillage-based monocrop resulted in the least stable yields. Our results suggest that intercropping maize with grain legumes in CA systems is a promising option for smallholder farming households to improve dietary diversity, dietary quality and stability of yields thus contributing to sustainable agriculture intensification while maintaining food and nutrition security.

Diversification of maize-based intercropping systems in tropical rainforest agroecosystem of Nigeria: productivity, profitability and soil fertility

Monocropping of maize is becoming unsustainable in the rainforest agroecosystem of Nigeria. This is due to the adverse impact of climate change such as increasing pests and disease infestations and erratic rainfall patterns coupled with underutilization of resources. Smallholder farmers in this tropical agroecosystems are in dire need of adaptive and resilient cropping systems to ensure food, nutrition, and livelihood security. Thus, this study aims to identify adaptive maize-based systems for the rainforest agroecology of Nigeria with high productivity, increased profitability, and enhanced soil fertility. The maize-based cropping systems comprised of maize sole; maize + cowpea; maize + groundnut; and maize + sweet potato. Results showed that the system productivity of maize + sweet potato (5.1 t ha–1) was significantly higher (P = 0.05) than maize sole (2.0 t ha–1); maize + cowpea (2.9 t ha–1); and maize + groundnut (2.5 t ha–1). Maize + sweet potato system ($ 808 ha–1) significantly increased the net income in terms of monetary profits compared to maize sole ($ 524 ha–1); maize + cowpea ($ 618 ha–1); and maize + groundnut ($ 560 ha–1). However, the net benefit-cost ratio of maize + sweet potato (1.17) and maize + cowpea (1.15) are similar. The effect of cowpea intercrop with maize affected the availability of nitrogen (N), phosphorus (P), and organic carbon (OC) in soil. The intercrops of maize + sweet potato and maize + cowpea in this agroecosystem are sustainable and adaptive intercropping systems that are capable of meeting the food requirements and income stability of farmers while maintaining the soil health. Crop diversification through intercropping in tropical smallholder farming systems can contribute to food security and maintenance of the soil ecosystem services.

Climate smart agriculture influences soil enzymes activity under cereal-based systems of north-West India

Soil enzyme activities are important indicators of changes in management practices in crop production systems. Measurements of different soil quality parameters are essential for assessing the impact of soil and crop management practices. Keeping this in view, an experiment was conducted to evaluate the enzyme activities namely, dehydrogenase (DHA), P-glucosidase, acid and alkaline phosphatase, fluorescein diacetate hydrolases (FDH), cellulase, urease and arylsulphatase in soil after 7 years of the experimentation with same management practices. The treatments were conventional rice-wheat system (Sc1), partial conservation agriculture (CA)-based rice-wheat-mungbean system (Sc2), partial climate smart agriculture (CSA)-based rice-wheat-mungbean system (Sc3), partial CSA-based maize-wheat-mungbean system (Sc4), full CSA-based rice-wheat-mungbean system (Sc5), and full CSA-based maize-wheat-mungbean system (Sc6). Soil samples were collected before sowing, maximum tillering, flowering, and at harvest of wheat crop from surface layer (0–15 cm soil depth). Partial CA-based system (Sc2) exhibited higher DHA activity over others. Also DHA activity in soil was higher at maximum tillering (16%), flowering (11%) and after harvesting (3%) in rice-based CSA systems (mean of Sc3 and Sc5) over maize-based systems (mean of Sc4 and Sc6). On average, P-glucosidase and alkaline phosphatase activity was significantly higher in soils of maize based systems than rice based systems. On average, improved practices (CA and CSA) based scenarios (Sc2-Sc6) recorded 15 per cent higher FDH activity over farmers’ practice/CT (Sc1). Significant interaction effect was observed between the managements and enzyme activities. The CSA managements were found beneficial in improving soil enzyme activities and thereby helping in improving nutrient cycling besides influencing other soil properties in long run.

Crop productivity, soil health, and energy dynamics of Indian Himalayan intensified organic maize-based systems

Crop productivity, soil health, and energy dynamics of Indian Himalayan intensified organic maize-based systems

How local gender norms and intra-household dynamics shape women’s demand for laborsaving technologies: insights from maize-based livelihoods in Ethiopia and Kenya

Where agriculture relies heavily on physical labor, small-scale mechanization can reduce labor constraints and contribute to higher yields and food security. Then, how to explain weak demand articulation for and adoption of small-scale mechanization, despite high labor burden? This study examines how intra-household gender dynamics affect women’s articulation of demand for and adoption of laborsaving technologies in maize-based systems in Ethiopia and Kenya. Using gender as a relational concept, and differentiating between different types of households, the analysis pulls together key underlying dimensions that shape women’s demand-articulation for small-scale mechanization. First, women’s labor often go unrecognized, and women typically are expected to work hard and not voice their concerns. Second, women generally lack access to and control over a range of resources, including land, income, and extension services. Third, the gender division of labor exacerbates this as women’s time poverty negatively affects their access to resources and information. Finally, decisions are primarily seen as men's domain, and women are often excluded. Our study contributes to the literature by offering a conceptual approach and methodology for the analysis of gender dynamics in relation to demand articulation and adoption of laborsaving technologies.

Tropical cloud forest plant endemism persistence within crop-fallow systems in a Mesoamerican hotspot area

Tropical montane cloud forests (TMCF) under natural disturbances have shown high endemism in early successional vegetation. However, little is known about anthropogenic disturbances and plant endemism in TMCF under ancient agricultural management. In this sense, I assessed the number of species, abundance, and frequency of endemic vascular plants in temporary plots of cultivated and young fallow areas from two maize-based systems: milpa shifting cultivation (MS) and semi-permanent cropping (SP) in Oaxaca, Mexico. Overall, both agricultural stages and systems harbored endemic species, seven in total, but most of such species were found in the fallow stage than in the cropping stage, and in the MS system than in the SP system. A single Asteraceae herbaceous endemic species (Melampodium mimulifolium) was commonly recorded in cultivated fields, but almost exclusive to the SP cropping system. Seven species were recorded in fallows, where the narrow-range endemic tree species Clethra integerrima (Clethraceae) was the most abundant and frequent, but almost exclusive to the MS cropping system. In more permanent and intensified agricultural systems within biodiversity hotspots, only ruderal endemic herbaceous species can persist. In contrast, in low intensity managed agricultural systems, like ancient agroforestry, not only can endemic tree species prosper, but also restricted endemic trees can be found. Indigenous agricultural systems in biodiversity hotspots should not be seen as a threat, but rather as complementary areas for endemism conservation.