Maize Farming System Research Articles

Nitrogen management and regulation for optimum NUE in maize – A mini review

AbstractModern agriculture has posed a great impact upon natural resources in terms of exploitation and their luxurious use. Ever increasing population pressure has exhausted the sustainable agricultural production system by exploiting land and water resources. High external inputs, required for high yield targets, are nowadays heavily dependent upon artificial sources and ways, amongst which nitrogen (N) is of global concern. Nitrogen is required by crops for active growth and photosynthetic machinery throughout the crop cycle. Among cereals, maize has the highest yield potential, hence it removes huge amounts of N and water from soil. To achieve high yields, farmers mostly use high dose of N fertilizers, causing soil, water and environmental pollution in the form of soil degradation, eutrophication and volatilization, thus reducing nitrogen use efficiency (NUE). This review critically focuses on N fertilizer management and regulation in maize farming systems with high population density. Achievements ha...

Stimulated fine root growth benefits maize nutrient uptake under optimized nitrogen management

Optimized nitrogen (N) management reduces total N application without sacrificing cropyield. However, the underlining mechanisms have not been well investigated, especially lackingthe evidence from roots. Here we performed a two-year field experiment with maize grownunder zero-N, conventional N and optimized N applications and examined grain yield, N,phosphorous (P) and potassium (K) uptake and root length in diverse diameter classes. Resultsshowed that both conventional N and optimized N managements significantly increased plantnutrient contents and grain yield compared with zero-N treatment, but no obvious differencewas observed between the two N-fertilized treatments. Notably, the response of differentnutrients to N application was not synchronous temporally over the growth period, followingthe order of N first, P second and K last. Though N application generally had minor impact ontotal root length and root biomass, optimized N regime significantly increased fine root(diameter ≤ 0.2 mm) length compared with conventional N at the eighth leaf emerged stage. Thestimulated fine root growth under optimized N management is beneficial for adequate N uptakeduring the key growth stage, which determines subsequent PK acquisition and final crop yield.Our findings highlight the importance of fine roots in maize NPK uptake and a betterunderstanding of the response of fine roots to changes in N availability may therefore be criticalfor optimizing N input in maize farming system

Analisis Keunggulan Kompetitif Ubikayu terhadap Jagung dan Kedelai di Kabupaten Lampung Tengah

Cassava is a major food crops which widely developed in Lampung province, it caused high adaptability, easily cultivated, smallest risk of failure, and high price. The study was objective to analyze competitive advantage of casava farming system compared to maize and soybean farming system. The activity were conducted at Central Lampung regency from April 2012 to February 2013. The primary data were obtained from respondents with sample of 90 farmers, using survey methods with structured interviews and questionnaires. Secondary data were obtained from the office of relevant agencies and BPS Lampung. Data analysis were financial analysis and competitive advantage analysis. The results showed that cassava farming more profitable than maize and soybean farming system income Rp.21.109.000/ha and R/C of 2,91 compared to corn farming income Rp.15.935.000 and R/C of 2,01 and soybean farming income Rp.5.187.800/ha and R/C of 1,48. Cassava farming system will be competitive compared corn and soybeans farming on the productivity levels at least 34.567 kg/ha and 20,788 kg/ha and cassava price at least IDR 654/kg and IDR 394/kg.

Behavioral Response of Multimammate Rat (Mastomys Natalensis, Smith 1834) on Selected Crude Pesticidal Plant Extracts

A plus maze arrangement was set at the Rodent Control Centre, Morogoro, Tanzania to investigate the rat behavior when subjected to maize seeds dressed with crude extracts of Lantana camara leaves (200 g), Ricinus communis seeds (150 g) and Euphorbia candelabrum latex (300 ml). The choice and no-choice test were set using a group of ten rats (5M+ 5F) in five plastic buckets. Each plastic bucket was fixed with RECONIX camera trap on top for picture capturing. Animals were provided with drinking water at the center bucket. In each experiment observation was made for four consecutive days where maize damaged seed, rat activities type (feeding, walking, resting, playing, sentry, grooming, biting others and approaching food) data were daily recorded. Results revealed that there was significant difference (p=0.00001) in maize damaged seed between treatments. With regards to nocturnal behavior, significant difference between treated and control on L. camara leaf (p=0.01301) and R. communis seed (p less than 0.00001) with no significant effect on E. candelabrum latex (p=0.93254) was observed. “Authors are grateful to the financial support provided by the Commission for Science and Technology (COSTECH), Tanzania that enabled accomplishment of this work.” No significant difference between treatments on the proportion of rat pictures approaching food (p=0.64821), biting each other (p = 0.91205), grooming (p=0.59964), feeding (p=0.27042), playing (p=0.36140), sentry (p=0.819821) and walking (p=0.06749). However, there was a significant difference on resting (p=0.02998). In general, this study recommends the use of R. communis for management of M. natalensis in maize farming system due low number of maize damaged seeds. However, several key questions remain, the most urgent being to extract the active compounds responsible for efficacy against rodent pest.

Reckoning the risks and rewards of fertilizer micro-dosing in a sub-humid farming system in Tanzania

Smallholder farmers are reluctant to risk investing in fertilizers. To understand how risk is perceived and how economic returns are distributed before the decision to invest in fertilizer use is made, needs a systematic approach using localized applications. This study assesses the profitability and net return variability of fertilizer micro-dosing (MD) in the sub-humid rain-fed maize (Zea mays L.) farming system in Tanzania. Useful data was gathered from a household baseline survey, water and nutrient limited calibrated yields, marginal costs and yields from farmers’ field trials, along with other information from expert and historical data. Crop yields, crop prices and prices for key production inputs (mainly fertilizer) were simulated for the net economic return distributions for maize under different fertilizer MD rates using the Economic and Nutritional Impact Assessment Model (FARMSIM), which is supported by Simulation and Econometrics to Analyse Risk (SIMETAR). The results show relative differences in stochastic returns between water and nutrient limited (without fertilizer MD) and with fertilizer MD scenarios. Farmers are likely to adopt fertilization technologies if best agronomic practices are promoted through farmer groups and field schools, fertilizers are re-packaged into small quantities for ease of purchase and access, and the coverage of subsidized fertilizers is increased.

Managing the water cycle in Kenyan small‐scale maize farming systems: Part 2. Farmers’ use of formal and informal climate forecasts

Forecasts can be an important component of water cycle management and farm decision making, particularly where rainfall is uncertain. In Kenya, the use of informal or indigenous forecasting (IF) is known to be widespread, but farmers also use more formal seasonal forecasting (SF) to make decisions in relation to the water cycle. A review of literature indicates that local knowledge is adaptable and often mixes indigenous knowledge and external information. In most cases, IF focusses on more local features and relates more to practical farm activities.Based on extensive interviews and focus groups of farmers in two study areas in Kenya, a majority of farmers from each area used IF, even though SF was also used. There were few farmer characteristics that explained the difference in the use of IF and SF. However, there were differences between the two study areas in how farmers interpreted SF and whether they used a combination of SF and IF. Furthermore there were differences in the local IF indicators used by farmers to identify the onset of the rainy season.To improve the acceptance of SF and increase its use, the information provided in SF needs to be easily incorporated into farmers’ current working knowledge, which might also include IF. This means that SF tools should be developed using participatory approaches to ensure the engagement of local farmers. WIREs Water 2016, 3:127–140. doi: 10.1002/wat2.1121This article is categorized under: Human Water > Water as Imagined and Represented

Managing the water cycle in Kenyan small‐scale maize farming systems: Part 1. Farmer perceptions of drought and climate variability

Farmer perceptions clearly influence the adoption of technology and adaptation to climate change, but may not be consistent with or captured by scientific measurements. There has been a significant research on how perceptions influence water resource management and adaptation to climate, but conclusions are unclear or contradictory. This research aimed to clarify what shapes perceptions and how this understanding can refine meteorological data collection and to make more relevant and useful tools for farmers to adapt to changes in the water cycle. A survey of 244 small‐scale maize farmers was conducted using a questionnaire and semi‐structured interviews in two districts in southern and western Kenya which differed in climate type and farming systems. Farmer perceptions of and adaptation to climate uncertainty were investigated and compared with meteorological data. Most farmers perceived changes in the patterns of rainfall and dry spells, including later onset of rains than in the past. They have already adjusted their management based on these perceptions, including later planting times. Despite this, analysis of meteorological data indicated no major trends in rainfall or dry spell patterns in the two regions. This research confirms that the perception that the water cycle is changing is based on a combination of climatic, economic, or social observations, and farmers are already changing their management to adapt to the perceived changes in climate. The article explores the reasons why these perceptions were inconsistent with the available meteorological data and suggests that research may improve the usefulness of meteorological data to farmers. WIREs Water 2016, 3:105–125. doi: 10.1002/wat2.1118This article is categorized under: Human Water > Water as Imagined and Represented

English

Declining land productivity and per capita food availability poses challenges to overcoming land degradation and poverty in sub-Saharan Africa. There is a need to identify ways of improving land productivity particularly among smallholders. This study investigated the contribution of integrated soil fertility management (ISFM) practices to both technical and allocative efficiencies in the maize farming system of Kenya. To determine efficiency gains from ISFM, we compared efficiencies of two groups of smallholders: those within the contact areas and their counterfactuals. We estimated Cobb-Douglas stochastic functions based on maize production data collected from a stratified sample of 373 farmers. The results indicate that farmers who applied ISFM were more efficient both technically and allocatively than those who did not. Application of ISFM practices increased technical and allocative efficiencies by 26 and 30%, respectively. However, other favourable factors are required for farmers to realize maximum efficiency gains from maize farming activity. They included farming experience, extension contacts, off-farm income and market access. Therefore, policies and practices aimed at enhancing farming efficiency in smallholder agriculture should address these factors. We recommend increased dissemination of ISFM technologies to the wider farming community through effective and participatory approaches to increase efficiency and enhance farm returns. Key words: Maize, land husbandry, productivity

Faidherbia albida on the Tonga Plateau of southern Zambia: an agroecological analysis

Faidherbia albida is a tree species indigenous to semi-arid regions of Africa that reportedly substantially increases maize (Zea mays) yields in its immediate vicinity. In southern Zambia, F. albida is widely used in indigenous maize farming systems and this has apparently increased over the past two decades. Using a combination of interviews, group meetings, and observations, this study sought to understand why this species seems to have recently been embraced, while other technological innovations apparently have not. We observed a bimodal age distribution of the trees in agricultural fields and posit that the missing cohorts were removed as weeds as a result of evolving notions of what constituted modern farming practices in the emerging maize economy. With subsequent research and social promotion of the beneficial effects of F. albida, farmers now allow the trees to grow in their fields. A holonic analysis points to the important relationship of F. albida to contexts that shaped past and current uses of the tree by farmers on the Tonga Plateau: information, maize, cattle, land tenure, and government policy. Advice promulgated by social promotion activities took root in farmer knowledge contexts because of positive regard for F. albida and timeless injunctions against cutting mature specimens. Furthermore, cultivation of the tree was highly compatible with other important contexts in which farmers operate. However, our research also revealed the potential for adoption of the tree to create new tensions arising from the strong gendering of work and crops in the region.

Estimating Soil Carbon in Agricultural Systems Using Ensemble Kalman Filter and DSSAT-CENTURY

Among various ways to sequester CO2 from the atmosphere, increasing soil carbon is an option that could also lead to increased agricultural productivity, especially in developing countries. In order to accept this option as a mechanism for reducing atmospheric CO2 levels, a reliable soil carbon accounting system needs to be developed. Soil carbon can be estimated from direct measurements, but measurements often have higher variability than annual soil carbon changes due to the uncertain nature of in-situ sampling methods and laboratory analysis techniques. To reduce such variability in soil carbon estimates, the estimation accuracy of an approach that assimilates measurements with simulated outputs from a complex crop model was studied. The DSSAT-CENTURY model and the ensemble Kalman filtering (EnKF) method were used to test if this approach can provide more reliable estimates of SOC over time than measurements alone. The EnKF was developed to estimate soil carbon, crop biomass, and a model parameter that specifies the rate of soil organic matter decomposition. A base-case simulation study was set up with a continuous maize farming system in Ghana for 20 years. Based on an identical twin test that used model-generated truth and measurement datasets, the EnKF estimates of soil carbon showed superior estimation accuracy to measurements with less uncertainty. In time, the uncertainty in soil carbon estimates based on annual sampling was reduced by about 60% using the EnKF method. The method was not effective in estimating the model carbon decomposition rate parameter, mainly because of the low correlations of that parameter with either soil carbon or crop biomass. However, even when uncertainties in measurements and model predictions were relatively high, estimates of soil carbon converged to the true value, although uncertainties in those estimates varied with measurement and model uncertainties. We conclude that the use of the EnKF method with the complex DSSAT-CENTURY model would provide more reliable soil monitoring system, but more research is needed to compare complex versus simple models in this approach.

Determinants of nutrient balances in a maize farming system in eastern Uganda

Soil nutrient depletion in Uganda is one of the leading environmental degradation problems threatening the livelihoods of most farmers in the region. In order to identify policy options that may be used to address the problem, this study was conducted with an objective of analyzing the determinants of flow and balances of nitrogen (N), Phosphorus (P), and Potassium (K) in Uganda. Data for this study were collected from 58 randomly selected farmers who participated in on-farm fertilizer trials and household surveys conducted in 2000 to 2001. Econometric models were used to analyze the determinants of soil nutrient flows and balances. Only 5% of the sample households had positive total NPK balances implying 95% of the farmers likely used unsustainable land management practices in the 2000/2001 season. If inorganic fertilizer were used to restore the mined nutrients, it would cost an equivalent of a fifth of the farm income. The results confirm the heavy reliance of smallholder farmers to soil fertility mining for their livelihoods. Agricultural potential, size of livestock herd, crop diversity, education, and having non-farm activities improve soil nutrient balances. This implies farmers need to be encouraged to grow crops and keep livestock in order to utilize the crop-livestock synergies. Education and non-farm activities in rural areas also need to be promoted as they contribute to more sustainable land management practices. Contact with extension agents initially accelerates soil nutrient depletion probably due to tendency of farmers to first adopt improved crop varieties without using fertilizer. Hence there is need for extension messages to emphasize adoption of both soil fertility and seed technologies. Farmers in high market access appear to deplete their soils more rapidly, pointing to the need to design policy mechanisms that would reduce soil nutrient depletion in high market access areas.

Habitat management strategies for the control of cereal stemborers and striga in maize in Kenya

Maize is the principal food and cash crop for millions of people in the predominantly mixed crop-livestock farming systems in Kenya. Stemborers and striga (Striga hermonthica) are major constraints to increased maize production in eastern Africa. An intercropping and trap crop system has been developed, using a ’push-pull’ strategy, for the control of stemborers in small scale maize farming systems. The ’push-pull’ strategy involves trapping stemborers on highly susceptible trap plants (pull) and driving them away from the crop using repellent intercrops (push). Napier grass (Pennisetum purpureum Schumach) and Sudan grass (Sorghum vulgare sudanense Stapf.) are used as trap plants, whereas molasses grass (Melinis minutiflora Beauv.) and two species of desmodium (Desmodium uncinatum Jacq. and Desmodium intortum Urb.) repel ovipositing stemborers. The integrated ’push-pull’ strategies were shown to increase parasitism of stemborers through attraction of parasitoids to one of the intercrops, molasses grass. The leguminous intercrop, silver leaf desmodium, drastically reduced damage to maize by the parasitic weed, striga. This aspect was further investigated and developed for integration **********w;th stemborer control. On-farm trials with farmers in Kenya have shown significant yield increases in maize farming.