Improved Crop Management Practices Research Articles

Analysis of potential yields and yield gaps of rainfed soybean in India using CROPGRO-Soybean model

To assess the scope for enhancing productivity of soybean ( Glycine max L. Merr.), the CROPGRO-Soybean model was calibrated and validated for the diverse soybean-growing environments of central and peninsular India. The validated model was used to estimate potential yields (water non-limiting and water limiting) and yield gaps of soybean for 21 locations representing major soybean regions of India. The average water non-limiting potential yield of soybean for the locations was 3020 kg ha −1, while the water limiting potential was 2170 kg ha −1 indicating a 28% reduction in yield due to adverse soil moisture conditions. As against this, the actual yields of locations averaged 1000 kg ha −1, which was 2020 and 1170 kg ha −1 less than the water non-limiting potential and water limiting potential yields, respectively. Across locations the water non-limiting potential yields were less variable than water limited potential and actual yields, and strongly correlated with solar radiation during the season ( R 2 = 0.83, p ≤ 0.01). Both simulated water limiting potential yield ( R 2 = 0.59, p ≤ 0.01) and actual yield ( R 2 = 0.33, p ≤ 0.05) had significant but positive and curvilinear relationships with crop season rainfall across locations. The gap between water non-limiting and water limiting potential yields was very large at locations with low crop season rainfall and narrowed down at locations with increasing quantity of crop season rainfall. On the other hand, the gap between water limiting potential yield and actual farmers yield was narrow at locations with low crop season rainfall and increased considerably at locations with increasing amounts of rainfall. This yield gap, which reflects the actual yield gap in rainfed environment, is essentially due to non-adoption of improved crop management practices and could be reduced if proper interventions are made. The simulation study suggested that conservation of rainfall and drought resistant varieties in low rainfall regimes; and alleviation of water-logging and use of water-logging tolerant varieties in high rainfall regimes will be the essential components of improved technologies aimed at reducing the yield gaps of soybean. Harvesting of excess rainfall during the season and its subsequent use as supplemental irrigation would further help in increasing crop yields at most locations.

Why do some farmers get higher yields? Multivariate analysis of a group of Uruguayan rice farmers

The technologies of precision agriculture were developed for application to site-specific crop management. Some of them require a high capital outlay, but two key component technologies, spatial analysis and global positioning systems, may both be obtained at relatively low cost. These technologies may be used profitably to improve crop management practices without the expenditures necessary for a full site-specific management program. In this paper we use exploratory spatial data analysis to study georeferenced rice production data collected on the farms of a group of Uruguayan rice growers. The objective was to identify the management practices that most distinguish farmers producing high yields from those producing low yields. A key challenge was to distinguish those differences in farmers’ management practices that were due to their different approaches to farming from those that were due to their responses to differences in the land quality of their individual fields. Using a combination of classification and regression trees and graphical analysis, the most distinguishing factors were identified to be early planting, adequate fertilization, and effective irrigation.

PAPER PRESENTED AT INTERNATIONAL WORKSHOP ON INCREASING WHEAT YIELD POTENTIAL, CIMMYT, OBREGON, MEXICO, 20–24 MARCH 2006 Sustainable improvement of wheat yield potential: the role of crop management

A significant proportion of wheat (Triticum aestivum L.) yield increases achieved at the farm level in the past can be attributed to improved crop management practices. The important role of crop management practices in increasing the yield potential in wheat sustainably is illustrated with recent research findings from North Dakota. In the dryer regions, no-till and crop rotations significantly improve yield and protect the productivity of the soil. Intensifying management in the wetter regions through increased plant populations and by nitrogen timing did not increase yield in 2005 while fungicide applied at flowering for scab control did. In one study genotype interacted with management, with the most disease-tolerant genotypes producing the highest yield when treated with fungicides. Identifying and exploiting positive genotype by management interactions offers a potential avenue for increasing yield potential in wheat in the future. Identifying or developing crop management practices that hold potential for synergistically improving the yield of genotypes is a significant challenge. Imposing management practices that hold promise for improving yield sustainably on breeding material during the selection process has scope for identifying genotypes with greater yield potential at the farm level when these management practices are employed.

Effects of precursor crops and management levels on the straw and grain yield of wheat at Horro highland, Western Oromiya

The sustainable production of wheat may be possible by integrating crop rotation with improved crop management practices. The maximum grain yield of wheat was observed when field pea was the precursor crop. The precursor crop and management levels showed a significant effect on the mean straw and grain yields of wheat. Field pea as precursor crop gave a better wheat grain yield with both improved and farmers' cultural practices. Both local and improved varieties gave a better response to management levels on the field pea precursor field. Local and improved varieties gave higher yields with intensive management and chemical fertilizer application. Field pea as precursor crop gave a combined grain yield advantage of 32% relative to barley. Management practices produced a combined grain yield advantage of 16 to 73% when field pea was the precursor crop, compared to barley. The use of field pea as precursor crop with improved management practices is essential to maximize wheat yields. Better grain yields and higher net returns were achieved with field pea as precursor crop compared to barley. Using field pea as precursor crop is the most successful management option for sustainable wheat production.

Agro‐Economic Characterization of Rice Production in a Typical Irrigation Scheme in Burkina Faso

Yield, yield gaps, input use, N‐use efficiency, productivity, and profitability of irrigated rice in Burkina Faso were determined for a typical irrigation scheme in the dry season (DS) 1999 and the wet season (WS) 2000. Objectives were to analyze agro‐economic constraints and opportunities and determine ways to overcome such constraints. The simulation model RIDEV was used to analyze farmers' crop management practices, revealing considerable deviation between actual and optimal timing of crop management interventions. This diversity of cropping practices caused considerable variation of internal efficiency of N (IEN), partial factor productivity of N (PFPN), N recovery fraction (RFN), rice (Oryza sativa L.) grain yields, and net benefits of N‐use. The results showed a clear relation between plant N uptake and yield (mean IEN of 48 kg grain kg−1 N uptake in farmer's fields), but the relation between N applied and yield was scattered. The PFPN varied from 16 to 52 kg grain kg−1 N applied (mean of 35 kg grain kg−1 N applied) due to a large range of fertilizer N recovery rates (RFN = 7–77%; mean of 37%). Farmers' average yields were 4.9 Mg ha−1 in the DS and 3.6 Mg ha−1 in the WS, but yields were very variable and ranged from 0.9 to 7.9 Mg ha−1 in the DS and from 1.0 to 7.9 Mg ha−1 in the WS. Yield gaps between average farmer's yield and best farmer's yield were high (3.0 Mg ha−1 in the DS and 4.3 Mg ha−1 in the WS), indicating considerable scope for yield increases in both seasons. Net benefits to irrigated rice cropping were mostly positive (avg. $418 (US) ha−1) in the dry season, but very low in the wet season (avg. $108 (US) ha−1). Partial budget analysis of fertilizer use revealed considerably lower value/cost ratios of fertilizer use in the wet season (mean V/C: 1.5) compared with the dry season (mean V/C: 2.9). It was concluded that improved crop management practices are the key to reach higher yields and financial returns without additional investments.

Monitoring root length density and root biomass in asparagus (Asparagus officinalis) with soil cores

Soil type, crop management practices, annual plant growth patterns, and seasonal changes in the soil environment all influence asparagus (Asparagus officinalis) roots. This study describes the dynamic changes in root growth that occur during the annual growth cycle of asparagus grown in two contrasting soil types and crop management systems. Root length density and biomass were estimated from soil cores (55 mm diam. × 0.2 m long) collected to 1 m in three locations adjacent to the row (0.15, 0.3, and 0.6 m from row centre). Samples were collected on six dates (early, or postharvest at early, mid, or late fern growth, and dormant period) between October 1999 and June 2000. Test sites varied with soil type (sandy loam or silt loam) and crop management system (normal 12‐week harvest or extended 15‐week harvest). Fleshy and fibrous roots were collected, root length density determined, and dry weights measured. Fleshy asparagus roots grew deeper in a sandy soil than in a silt soil, had higher dry matter content in silt than in sandy soil, and greater root length in a silt compared to a sandy soil. Fibrous root length density was greater during fern growth than during harvest, in a sandy versus a silt soil and at shallow versus deep sampling depths. Sampling date, soil depth, and sample location all significantly influenced asparagus fleshy and fibrous root biomass. Soil cores accurately estimated both total fleshy root length density and dry matter content when compared to the more time‐consuming complete root excavation. Results can be used to improve crop management practices, predict root biomass, and increase our understanding of the dynamics of root development in asparagus.

ESTIMATING ROOT LENGTH DENSITY AND BIOMASS IN ASPARAGUS

Soil type, crop management practices, annual plant growth patterns and seasonal changes in the soil environment all influence asparagus roots. This study describes the changes that occur in root growth over time in two contrasting soils and crop management systems. Soil cores (5.5-cm diameter x 20-cm long) were collected to one meter in on six dates (pre/postharvest, early/mid/late fern growth, and dormant period) and in three locations (15/30/60 cm from row) in 1999-2000. Sites varied with soil (sandy loam or silt loam) and by crop management system (normal 12-week harvest or extended 15-week harvest). Fibrous and fleshy roots were collected and root length density determined. Soil type significantly altered rooting depth (sandy>silt), dry matter content (silt>sandy) and root length density (silt>sandy) of fleshy roots. Fibrous root length density varied with sampling date (harvest silt) and sampling depth (shallow>deep). Sampling date, soil depth and sample location significantly influence asparagus fleshy and fibrous root biomass. Soil cores accurately estimated both total fleshy root length density and dry matter content when compared to the more time consuming complete root excavation. Results can be used to improve crop management practices, predict root biomass and increase our understanding of the dynamics of root development in asparagus.

Agriculture Intensification and Ecologically Sustainable Land Use in Niger: A Case Study of Evolution of Intensive Systems with Supplementary Irrigation

ABSTRACT In Niger, a breakdown of the bush-fallow system, low crop yields and reduced availability of communal land have resulted from increasing population pressure. Agricultural intensification is critical to the future development of the region. Intensification of agricultural production in Niger must include adoption of sustainable yield increasing technologies, fertilizer use, supplementary irrigation and/or water conservation, high yielding cultivars and improved crop management practices. On-farm constraints analysis of crop productivity and technologies assessment was carried out in two irrigated perimeters: the Konni surface irrigation and the Djirataoua deep well system where supplemental irrigation is provided to rainy season crops in the event of long dry spells, and full irrigation is supplied to dry season crops. Konni is located in southern Niger, approximately 13°48'0′N, 5°15'0′E at approximately 257 m altitude; Djirataoua is located further east, approximately 13°20'0′N, 7°7'60′E at approximately 368 m altitude, near Maradi, which is located at approximately 13°28°60′N, 7°5′60E, approximately 376 m altitude. In both the Konni and Djirataoua irrigation systems, use of supplementary irrigation has enhanced cropping intensity and crop productivity per unit area (yield) while generating greater employment opportunity. Analysis of long-term crop productivity trends during 1980–1997 revealed that sustainability of gained productivity is possible through agricultural intensification over years without any sign of productivity decline. These results show that the use of agriculture intensification technologies plays a crucial role in sustainable, increased crop production in the Sahel. The results of our diagnostic survey in these two perimeters showed that the major constraints to increased productivity are low fertilizer use, poor nutrient use efficiency, the lack of well adapted, high yielding varieties or hybrids, poor crop establishment and plant protection in farmers fields, and inappropriate input and output pricing. On-farm evaluation of the improved technologies, namely improved varieties or hybrids and optimal fertilizer use with optimal supplementary irrigation, resulted in a 35% increase in grain yields at the farm level. The lesson learned from this study is that developing sustainable agricultural production systems in Niger with higher yields, or production per unit area, than present-day yields depends upon supplementary irrigation if or where potential exists, and upon promotion of fertilizer use, high yielding cultivars and other innovative production technologies. This strategy will help reduce frequency and intensity of food shortages and will ultimately help reduce the incidence of poverty and starvation in Niger.

Improving the productivity and profitability of irrigated rice production in Mauritania

Yield, input use, productivity and profitability of irrigated rice in Mauritania were analyzed during the 1997 wet season (July–December) in the Senegal river delta and middle valley, in collaboration with 42 large farmers and extension staff. Objectives were to determine agronomic constraints to rice cropping and to evaluate alternative crop management strategies aimed at overcoming these constraints. Grain yields ranged from 0.9 to 8.5 t ha −1 and averaged 4.4 t ha −1. Based on crop simulations, average yield potential in farmers' fields was estimated at 8.6 t ha −1, indicating considerable scope for increased yields. Our survey identified the following main agronomic constraints: (i) mismatches between timing of nitrogen (N) fertilizer applications and critical N demanding growth stages of the rice plant; (ii) non-use of phosphorus (P) fertilizer on P deficient soils; (iii) largely neglected or inefficient weed management and (iv) late harvesting, often due to non-availability of combine harvesters. Based on these results we tested improved nutrient and weed management practices with farmers during the 1998 wet season. Improved nutrient management (i.e. T1: application of 20 kg P ha −1 and 150 kg N ha −1 in three splits at start tillering, panicle initiation and booting) increased yields by 0.9 t ha −1. Improved weed management (i.e. T2: application of 6.0 L propanil ha −1 and 2.0 L 2,4- d-amine ha −1 at 2–3 leaf stage of weeds) also raised yields by 0.9 t ha −1 as compared to farmers' practice (TP). The combined effect of T1 and T2 (i.e. T3) was additive: improving both nutrient and weed management raised yields by 1.8 t ha −1 over average farmers’ yields of 3.9 t ha −1, i.e. an increase of almost 50%. The improved crop management practices were highly profitable: compared to farmers’ practice, net benefits increased by 40% for T1 and T2 and by about 85% for T3, with minimal additive investments. Inputs used for T3 are relatively easily available in Mauritania. We concluded that increased farmer awareness of the profitability of improved nutrient and weed management may have a tremendous impact on the competitiveness of rice production in Mauritania

REDIRECTION OF PRECIPITATION BY A CORN CANOPY AND RELATED SOILWATER STATUS1*

Redirection of precipitation by a crop canopy significantly affects the distribution of water entering soil. This knowledge can be used to improve crop management practices for protecting ground water. Over a 4-y period, rain and/or irrigation water was collected at 8 equidistant positions between corn (Zea mays L.) rows. Soil water status was measured to a 0.3-m depth in the same relative positions. Wind direction and speed, and crop canopy development influenced the location where throughfall entered the soil surface and resultant soil water content. Stemflow increased to > 60% of incoming precipitation with canopy closure in most years. These large amounts of water entering the soil as stemflow increased percolation in the row and soil water content below the row, the zone of greatest depletion of plant available water. Associated with canopy closure, reduced throughfall reached the soil surface within 0.2 m of the row; hence, a reduced potential for leaching of agrichemicals applied in this area. * Minnesota Agric. Exp. Stn. Scientific J. Series No. 991250097.

Adoption, management, and impact of hybrid maize seed in India

This paper presents results of a 1995 survey of 864 maize-growing households in six states that account for more than 70% of India's maize area: Andhra Pradesh, Bihar, Karnataka, Madhya Pradesh, Rajasthan, and Uttar Pradesh. The current adoption of improved open-pollinated maize varieties (OPVs) and hybrids is quantified, the relationship between adoption of improved germplasm and use of improved crop management practices is examined, the economic impacts of adoption are estimated, farmers' seed procurement and management practices are described, and implications for maize research and development policy are discussed. On the whole, the survey results confirm that India's national maize seed industry is expanding rapidly. Since seed policy reforms were introduced in the late 1980s, the area planted to improved OPVs and hybrids has grown rapidly, and adoption of improved germplasm has fueled important changes in farmers' crop management practices. However, special policy measures may be needed to ensure that the benefits of improved germplasm are widely shared, such as the introduction of targeted input subsidies designed to reduce the cost of adopting improved seed and complementary inputs, government investment in irrigation infrastructure to reduce production risk in drought-prone environments, and market development initiatives to provide small-scale producers with access to stable and reliable outlets where they can sell surplus grain.

Soil and water conservation and improved crop management effects on watershed productivity in Andhra Pradesh, India

AbstractSoil and water conservation and improved crop management programs were initiated in 1983 to increase the productivity of a dryland vertisol watershed in the state of Andhra Pradesh in the semi-arid tropical region of India. This was one of 47 model watersheds developed by the Government of India. The integrated program consisted of measures to conserve soil and water, such as a percolation tank, grading, checks, and deep tillage, on which were superimposed improved crop management practices (e.g., cultivars, fertilizers, and timeliness in operations), carried out with the farmers' cooperation and partial payment. All participants were surveyed in 1983, before starting the program, and 1988, after completing the program. The equilibrium water levels in open wells increased about 50 cm, which allowed sugarcane to be introduced. About 10% additional area was reclaimed and cultivated after construction of a diversion dam. Fodder supply improved because of the growth of natural grasses on terraces formed by stone checks in waterways. Soil and water conservation efforts reduced runoff about 26%. Ground cover increased by 38% because of increased cropping intensity, and income per capita grew by 67% per year. Thus, the integrated approach conserved natural resources and improved productivity.