Groundnut/Maize/Cassava Intercrop Yield Response to Fallow Age, Cropping Frequency and Crop Plant Density on an Ultisol in Southern Cameroon

More flexible and effective weed control with herbicide-tolerant B. napus canola allows for additional seeding management options, such as fall (dormant) and early spring (ES) seeding. Field experiments were conducted at Lacombe and Beaverlodge (1999–2001), Didsbury (1999–2000), and Lethbridge (2000–2001), Alberta, Canada, primarily to evaluate the effect of fall (late October-November), ES (late April-early May), and normal spring (NS) (ca. mid-May) seeding dates on glufosinate-, glyphosate-, and imidazolinone-tolerant canola development and yield. Fall seeding resulted in 46% lower plant density and nearly double the dockage than spring seeding. ES-seeded canola had 19% higher seed yield and 2.1% higher oil content than fall-seeded canola. ES seeding significantly increased yield compared to fall-seeded canola for 8 of 10 site -years or compared to NS seeding for 4 of 10 site-years; ES-seeded canola equalled the yield of NS-seeded canola for 6 of 10 site-years. Yield response to seeding date did not differ among herbicide-tolerant cultivars. Seeding date did not influence root maggot damage. Seeding canola as soon as possible in spring increases the likelihood of optimizing canola yield and quality compared to fall seeding and traditional spring seeding dates. Key words: Dormant seeding, seeding management, root maggot, herbicide-resistant crops, yield components, operational diversity

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Soybean Seed Yield Response to Plant Density by Yield Environment in North America

Agronomy Journal ◽

10.2134/agronj2018.10.0635 ◽

2019 ◽

Vol 111 (4) ◽

pp. 1923-1932 ◽

Cited By ~ 11

Author(s):

Walter D. Carciochi ◽

Rai Schwalbert ◽

Fernando H. Andrade ◽

Geomar M. Corassa ◽

Paul Carter ◽

...

Keyword(s):

North America ◽

Seed Yield ◽

Plant Density ◽

Soybean Seed ◽

Yield Response

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Corn Response Across Plant Densities and Row Configurations for Different Moisture Environments

International Journal of Agronomy ◽

10.1155/2020/4518062 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10

Author(s):

Kipling S. Balkcom ◽

Kira L. Bowen

Keyword(s):

Cover Crops ◽

Plant Density ◽

Conservation Tillage ◽

Summer Rainfall ◽

Moisture Stress ◽

Yield Response ◽

Corn Yield ◽

Measured Variable ◽

Irrigation Level ◽

Plant Densities

Corn (Zea mays L.) production in the Southeast can be negatively impacted by erratic summer rainfall and drought-prone, coarse-textured soils, but irrigation combined with conservation tillage and cover crops may support greater plant densities arranged in different row configurations to improve yield. We examined five site-years of data across two soil types in Alabama to compare corn yields in a conservation system across three plant densities for single- and twin-row configurations in dryland and irrigated moisture regimes. Treatments were arranged with a split plot treatment restriction in a RCB design with three replications. Main plots were irrigation level (no irrigation and irrigation), and subplots were a factorial arrangement of three plant densities (5.9, 7.4, and 8.9 plants m−2) and row configurations (single and twin). A moisture environment (low and moderate) variable, defined by growing season rainfall, was used to average over site-years. In general, irrigation in the moderate-moisture environment improved each measured variable (plant height, stover yield, corn yield, and test weight) and decreased grain N concentration and aflatoxin levels compared to the low-moisture environment with no irrigation. Benefits of increased rainfall and irrigation to reduce soil moisture stress across drought-prone soils were evident. Pooled results across all site-years indicated no yield response as plant density increased, but greater yields were observed with the greatest plant densities in the moderate-moisture environments. No advantage for twin-row corn production was observed across five site-years in Alabama, which indicates either row configuration can be successfully adopted.

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Yield response of narrow-leafed lupin plants to variations in pod number

Australian Journal of Agricultural Research ◽

10.1071/a97092 ◽

1998 ◽

Vol 49 (1) ◽

pp. 63 ◽

Cited By ~ 9

Author(s):

J. A. Palta ◽

C. Ludwig

Keyword(s):

Seed Size ◽

Seed Yield ◽

Plant Density ◽

Yield Response ◽

Seed Number ◽

Subsequent Removal ◽

Seed Filling ◽

Specific Number ◽

Pod Number ◽

Number Of Seeds

The effect of pod number on the seed yield and components of seed yield was examined for narrow-leafed lupin (Lupinus angustifolius L.) grown at a plant density of 36 plants/m2 in both the glasshouse and the field. Diflerent numbers of pods per plant in the glasshouse-grown lupin were generated by the application of N6-benzylaminopurine (BAP) to a specific number of flowers to ensure artificially that they set pods, and the subsequent removal of the remaining untreated flowers. Pod number ranged from 6 to 65 pods/plant in the glasshouse and was naturally distributed from 2 to 22 pods/plant in the field. Increases in seed yield per plant occurred as pod number per plant increased from 2 to 30 pods. No further increases in seed yield resulted when pod number per plant increased from 30 to 55 pods. Seed yield per plant was depressed as pod number increased from 55 to 65 pods. Seed size fell as pod number per plant increased over 20 pods and was less affected once the number of seeds per pod was reduced. The reduction in seed number per pod resulted from an increase in the number of seeds that aborted during seed filling. The data suggest that at a plant density of 36 plants/m2 there is potential for improving seed yield per plant by increasing the number of pods that reach maturity, provided it does not exceed 30 pods/plant. However, if consideration is given to producing large seeds, often preferred by buyers, the number of pods per plant should not exceed 20 pods.

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Estimating the economic optimal target density of hybrid canola based on data from a western Canadian meta-analysis

Canadian Journal of Plant Science ◽

10.1139/cjps-2020-0162 ◽

2020 ◽

Author(s):

Murray D. Hartman ◽

Scott R. Jeffrey

Keyword(s):

Plant Density ◽

Meta Analysis ◽

Yield Response ◽

Western Canada ◽

Seeding Rate ◽

Optimal Density ◽

Herbicide Resistant ◽

Plant Densities ◽

Optimal Target ◽

The Relationship

Canola production in western Canada has expanded such that in many regions canola area rivals the area seeded to wheat. This change can be mainly attributed to adoption of herbicide resistant hybrid varieties, and resulting higher relative profitability. Producers responded to higher seed prices by reducing seeding rates, leading to plant densities that were often lower than industry recommendations. The study objectives were to examine canola yield response to plant density and assess economically optimal density levels relative to industry recommendations and grower practices. A meta-analysis approach was applied to yield response and plant density data with herbicide resistant hybrid canola from multiple studies. Three alternative marginal yield-density functions were estimated and used to calculate economically optimal plant density. Sensitivity of results to key parameters was assessed. Resulting optimal density levels under recent average prices, seed size and emergence were 62-73 plants m-2, consistent with industry recommendations for western Canada. Recent field surveys report lower densities than this range, suggesting that producers are seeding at less than optimal rates. However, there is significant uncertainty associated with canola production, and interaction of seeding rate with other factors. These would impact on optimal plant density, although much of the uncertainty remains until well after seeding. The empirical results represent a foundation for development of more detailed models, highlight the significance of the relationship between plant density and economically optimal yield, and suggest the need to develop decision making tools to support producers in making canola planting decisions.

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