Red:Far-Red Light Effects on Corn Growth and Productivity in Field Environments

Weed Science ◽  
2009 ◽  
Vol 57 (2) ◽  
pp. 208-215 ◽  
Author(s):  
Melinda Y. Markham ◽  
David E. Stoltenberg

Increased reflection of far-red light among plants can lower the red:far-red ratio (R:FR) of horizontally-propagated light before substantial shading among plants occurs. Although previous research suggests that altered R:FR can affect corn growth, it is not understood how early-season low R:FR (associated with higher plant densities in corn–weed communities than in weed-free corn) affects corn productivity in the field. We conducted field experiments from 2005 to 2007 to determine the effects of reduced R:FR on corn growth and yield. Corn was established at 53,800 plants ha−1for a control R:FR treatment (weed-free corn) and at 107,600 plants ha−1for a low R:FR treatment (simulated corn–weed community). The low R:FR treatment was thinned to the control plant density at V7 corn (seven fully-expanded leaf collars), which simulated total weed removal. Before thinning, R:FR (645:735 nm) at V7 corn in the low R:FR treatment (0.23) was less than 50% of that in the control R:FR treatment (0.49) across years. In 2005, stalk diameter, stem length, stem mass, leaf mass, specific leaf area, and total plant mass were less for V5 corn in the low R:FR treatment than in the control R:FR treatment. In 2006, V5 corn was taller in the low R:FR treatment than in the control R:FR treatment, but other morphological characteristics were similar between treatments. The shoot:root ratio of V5 (five fully-expanded leaf collars) (2005) and V7 corn (2006) was not affected by R:FR treatment, nor was shoot mass and grain yield of R6 corn (physiological maturity). Measurements in 2006 indicated that soil moisture and nutrient availability were not limiting and did not differ between treatments. Early-season R:FR in simulated corn–weed communities was similar to that in in situ corn–weed communities. These results suggest that low R:FR typical of early-season corn–weed communities was not associated with corn grain yield loss under field conditions in which water and nutrients were not limiting resources.

1990 ◽  
Vol 30 (3) ◽  
pp. 395 ◽  
Author(s):  
RC Muchow ◽  
JD Sturtz ◽  
MF Spillman ◽  
GE Routley ◽  
S Kaplan ◽  
...  

Field experiments were conducted at Berrimah, Douglas Daly and Katherine in the Northern Territory (NT) during the 1987-88 and 1988-89 wet seasons to obtain yield data for kenaf (Hibiscus cannabinzis L. cv. Guatemala 4) grown under rainfed and irrigated conditions. Under rainfed conditions, maximum stem yield was obtained from sowings early in the wet season. Yield decreased with delay in sowing until the late-December-January period. The maximum rainfed stem yield at Katherine in an above-average rainfall season was 18 400 kg/ha. The maximum yield in a below average rainfall season was 11 700 kg/ha at Katherine, 9200 kg/ha at Douglas Daly and 9400 kg/ha at Berrimah. The applicability to the NT of growth and yield relationships established for irrigated kenaf in the Ord Irrigation Area (OIA) was assessed. The yield potential under irrigated conditions in the NT (21 600 kg/ha at 131 days after sowing) was higher than that reported elsewhere in Australia for the same growth period, but similar to that reported elsewhere for longer growth duration (180-300 days). In the NT, in contrast to the OIA, stem yield showed little or no response to N fertilisation. Stem yield was not related to N uptake, and at high levels of N application, there was marked N accumulation in the stem. Kenaf was able to accumulate up to 110 kg N/ha from the soil reserve where no N was applied. The yield response to plant density varied with the yield level and was similar to that in the OIA. Bark and core yield could be estimated directly from biomass, and indirectly from stem length and plant density, over a wide range of yield levels and cultural conditions. It was concluded that data relating to yield potential and response to N fertilisation cannot be transferred directly from the OIA to the NT.


Weed Science ◽  
1988 ◽  
Vol 36 (1) ◽  
pp. 37-42 ◽  
Author(s):  
Don W. Morishita ◽  
Donald C. Thill

Field experiments were conducted in 1983 and 1984 to measure the interference of wild oat (Avena fatuaL. # AVEFA) removed at various stages of development (two to three leaves, two to three tillers, two nodes, and heading), plus treatments with wild oat not removed, and wild oat-free stands on the growth and yield of spring barley (Hordeum vulgareL. ‘Advance’). The final plant density of barley and wild oat was 160 and 170 plants/m2, respectively. Based on aboveground barley biomass and yield, the critical duration of wild oat interference began about the two-node stage and continued until maturity of the barley. Wild oat interference reduced barley biomass, the number of tiller heads/plant, tiller heads/unit area, and tiller grain yield, but not the number or grain yield of the main-stem heads. Wild oat did not affect the soil matric potential or the barley total plant and soil nitrogen contents. However, wild oat did reduce total water and turgor potential in barley at the boot stage of growth, which may have affected tiller head formation.


2020 ◽  
Vol 41 (4) ◽  
pp. 1107
Author(s):  
Antonio Germano Carpim Rocha ◽  
Eduardo Lima do Carmo ◽  
Guilherme Braga Pereira Braz ◽  
Luiz Fernando Ribeiro Júnior ◽  
Carlos César Evangelista de Menezes ◽  
...  

Grain sorghum has been cultivated extensively in the Central-West region of Brazil in succession with soybean, since the species tolerates the low rainfall conditions recorded during this growing season. Phytotechnological adjustments for sorghum are still necessary in order to exploit the maximum yield potential of the crop. In this context, altering the plant distribution may result in better utilization of the growing area with a consequent increase in grain yield. On this basis, field experiments were conducted with two grain sorghum hybrids, replicated in two different locations, in order to evaluate the effect of the spatial arrangement of plants on the agronomic performance of grain sorghum. The design was a randomized complete block design in a 2 x 4 factorial scheme, with five replications. The factors consisted of two row spacings (0.50 and 0.25 m) and four plant densities: 120, 180, 240, and 300 thousand plants ha-1. The sorghum hybrids used were 1G244® and 1G100®. At harvest, morphological characteristics, yield components, and grain yields were evaluated. Row spacing did not influence the characteristics evaluated except for the plant height of for both hybrids, in addition to the stem diameter, tillering, and mass of a thousand grains for 1G100®. The increase in plant density provided an increase in grain yield, being the highest number of panicles per area the most expressive component for this behavior.


1990 ◽  
Vol 41 (3) ◽  
pp. 449 ◽  
Author(s):  
GK McDonald

The growth and yield of two lines of uniculm barley, WID-103 and WID-105, were compared over a range of sowing rates (50-400 kg/ha) with the commercial varieties Galleon and Schooner. The experiments were conducted at Strathalbyn, S.A., in 1986, 1987 and 1988 and at the Waite Agricultural Research Institute in 1987. A third tillered variety, Clipper, was included in the comparison in 1988. Over the three years plant populations measured early in the season ranged from 39/m2 to 709/m2, and grain yields from 97 to 41 1 g/m2. Dry matter production at ear emergence increased with greater plant density, and both the tillered varieties and the uniculm lines showed similar responses to higher sowing rates. At maturity, dry matter production of the tillered barleys was greater than or equal to that of the uniculms and the harvest indices (HIs) of the two types were similar. Consequently, grain yields of the tillered types were greater than or equal to the yields of the uniculms. Over the four experiments the tillered varieties had a 6% higher yield. The number of ears/m2 was the yield component most affected by plant density in both the tillered and uniculm barleys. The uniculm lines had more spikelets/ear, but tended to set fewer grains/spikelet and produce smaller kernels. The experiments failed to demonstrate any advantage of the uniculm habit to the grain yield of barley. These results differ from previous experiments that showed that a uniculm line, WID-101, had a higher yield than the tillered variety Clipper. It is suggested that the uniculm habit per se was not the cause of this higher yield, but its higher HI resulted in it outyielding Clipper. Current varieties, however, have HIs similar to the uniculm lines and yield equally to or more than the uniculm barleys examined. To further improve the grain yield of uniculm barley, greater dry matter production is necessary as the HIs of these lines are already high.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Guangzhou Liu ◽  
Wanmao Liu ◽  
Yunshan Yang ◽  
Xiaoxia Guo ◽  
Guoqiang Zhang ◽  
...  

Abstract Marginal superiority is a common phenomenon in crops, and is caused by the competitiveness of individual plant for resources and crop adaptability to crowded growth conditions. In this study, in order to clarify the response of marginal superiority to maize morphology and plant-density tolerance, field experiments without water and nutrition stress were conducted at Qitai Farm in Xinjiang, China, in 2013–2014 and 2016–2019. The results showed that no more than three border rows of all the cultivars had marginal superiority under high density, about 90% of all the cultivars had no more than two border row that had marginal superiority and a significant negative correlation was observed between marginal superiority and population grain yield (first border row: y = − 2.193x + 213.9, p < 0.05; second border row: y = − 2.076x + 159.2, p < 0.01). Additionally, marginal superiority was found to have a significant positive relationship with plant density (first border row: y = 6.049x + 73.76, p < 0.01; second border row: y = 1.88x + 95.41, p < 0.05) and the average leaf angle above the ear (first border row: y = 2.306x + 103.1, p < 0.01). These results indicated that the smaller the leaf angle above the ear, the weaker the marginal superiority and the higher the grain yield. It suggests that the magnitude of marginal superiority in the border rows can be an indicator for plant-density tolerance under high density. What’s more, cultivars with small leaf angle above the ear can be selected to weaken the marginal superiority and improve grain yield under high plant density. Conversely, cultivars with a large leaf angle above the ear can be selected to achieve higher individual yield in intercropping systems with no more than four rows alternated with other crops.


1974 ◽  
Vol 83 (1) ◽  
pp. 125-133 ◽  
Author(s):  
P. C. Longden ◽  
R. K. Scott ◽  
D. W. Wood

SUMMARYFrom monogerm sugar-beet seed as harvested non-viable fruits have to be eliminated, multigerm ones rejected and the size made sufficiently uniform for use in precision drills. Seed which had been gently rubbed to remove some of the cortex was graded for diameter, thickness and by aspiration, either singly or in combination. Effects of grading were determined by laboratory germination tests, radiography and field sowings in which seedling emergence and crop growth and yield were recorded.Grading by thickness was effective in removing multigerm fruits. Grading by aspiration and diameter rejected non-viable seed and reduced the variation in size. By combining all three grading methods, samples of seed of 80% germination and 90% monogermity were produced, provided the seed lot as threshed gave at least 50% germination. True seed weight increased with fruit diameter but only the first aspiration was effective in removing light true seeds. Radiography showed that both aspiration and, to a less extent, grading by diameter were effective in removing most empty fruits but neither eliminated those with shrivelled seed. The field experiments confirmed that increase in fruit diameter or aspiration gave more seedlings. Even at uniform, high plant density, sugar yields were less from the smallest (less than 3 mm diameter) than from the other grades of seed. The initial aspiration also improved sugar yield but further aspiration decreased yield.


Crop Science ◽  
2010 ◽  
Vol 50 (1) ◽  
pp. 273-280 ◽  
Author(s):  
Melinda Y. Markham ◽  
David E. Stoltenberg
Keyword(s):  

2019 ◽  
Vol 50 (6) ◽  
Author(s):  
Al-Mohmadi & Al-Ani

A field experiment was condueted at the experimental Farm, College of Agriculture University of AL-Anbar in replace location (Abu-Gheaib) in spring season of 2017. While in Fall season it was applied at AL-saqluwiya-Anbar Province 10 km west north of Falluga city to study the effect of four levels of licorice extractor (Glycyrrhiza glabra L.) (0,2,4 and 6) g.L-1 water and three (53,333, 66,666 and 88,888 plant) plant.ha-1. On growth and grain yield of Sorghum cv. Rabih. The experiment was applied using R.C.B.D. arranged in split plots with three replications. levels of plant densities were used as main-plot, while licorice extractor were used as sub-plot. Foliar application of licorice extractor was applied during vegetative growth. The results showed that, high plant density (88888) plant.h-1 significantly increase plant height and leaf area index, while most of traits were not significantly influenced by plant density including grain yield. Results revealed that foliar application of licorice extractor with 2,4,6 g.L-1 of water significantly influenced grain yield in spring season compane with control treatment and it is amounted to (9.62, 9.55 and 9.78) t.h-1 respectively. There were significant interaction between Licorice extractor and plant density in spring and fall season in grain yield. The higher grain yield of 10.31 and 10.33 t.h-1 were obtained when sorghum plants were sowing at hight density and sprayed with Licorice extractor at level          4 g.L-1 respectively


2020 ◽  
Vol 41 (6supl2) ◽  
pp. 2967-2976
Author(s):  
José Geraldo da Silva ◽  
◽  
Enderson Petrônio de Brito Ferreira ◽  
Virgínia Damin ◽  
Adriano Stephan Nascente ◽  
...  

The common bean production system is majorly based on the use of granular fertilizers to provide nutrients for the crop. Studies on the use of liquid fertilization at an appropriated depth and, seed inoculation with Rhizobium tropici can provide significant increases in the grain yield of the common bean. The objective of this study was to determine the growth and productivity of common bean as affected by N-P formulations, application depths and the inoculation with R. tropici. Field experiments were carried out in 2015 and 2016 cropping years using a complete block design, in a 2x2x2 factorial arrangement, with four replicates. The treatments involved the combination of N-P formulation (granular and liquid), two application depths of the N-P formulation (6 and 12 cm) and with or without rhizobia inoculant. The plant density (PD), number of pods (NP), number of grains (NG), mass of 100 grains (M100) and grain yield (GY) were determined. The granular and liquid N-P formulations provided similar results for PD, NP, NG, and GY of common bean. Similarly, the application depth of the N-P formulations did not affect GY. Inoculation of the seed with R. tropici stimulated NP and NG, increasing GY. Growth and productivity parameters were equally affected by the type of formulation and application depth; however, GY was greater with rhizobial inoculant. Thus, the liquid N-P formulation, applied at 6 cm depth, associated with rhizobial inoculant can improve the crop management providing better control of application uniformity, minimal soil mobilization, less fuel consumption, and increased grain yield.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Mohamed A. I. Mansour ◽  
Darin M.R.El- Bolok ◽  
Ahmed B. El- Mansy

Broad bean plants (Vicia faba L.) were cultivated in two field experiments at the Experimental Station of the Faculty of Environmental Agricultural Sciences, Arish University, North Sinai, Egypt, during 2018/2019 and 2019/2020 seasons under North Sinai condition, to study the effect of soil application of some biofertilizers and foliar spray with some wild plant extracts on broad bean plants. Biofertilizer treatments contained combination of Arbuscular Mycorrhizal Fungi (AMF) + Trichoderma harzianum + Rhizobium leguminosarum. Three wild plant extracts treatments; i.e., Qeysoom Gebeli (Achillea fragrantissima L.), Harmal (Peganum harmala L.) and Mitnaan (Thymelaea hirsute L.) were sprayed on plants. Treatments were arranged in a randomized complete block design with three replicates in split plot system. The results indicated that biofertilizers had significant effected of all studied traits in both seasons. Foliar spraying of Thymelaea hirsute extract had the highest stimulation effects on spores count, root colonization, mycorrhizal status, and weight of non-active nodules, broad bean plant growth characters; i.e. stem length, number of branches per plant, leaf area, and shoot fresh and dry weight as well as both of fresh and dry weight of roots. Both of Thymelaea hirsute and Achillea fragrantissima extracts combined with biofertilizer treatment had significant effects on yield and its components (pod length, number of pods per plant, average pod weight total yield per plant, and weight of seeds per pod) in both seasons. The combination between Thymelaea hirsute and biofertilizer was the superior interaction treatment of this study.


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