Juvenile lodging in barley: a yield-depressing phenomenon

1975 ◽  
Vol 26 (2) ◽  
pp. 231 ◽  
Author(s):  
CJ Gardener ◽  
AJ Rathjen
Keyword(s):  
Yield Components ◽  
Stem Elongation ◽  
South Australia ◽  
Leaf Length ◽  
High Fertility ◽  
Nitrogen Application ◽  
Area Index ◽  
Wire Grid ◽  
Plant Densities ◽  
The Relationship

A field experiment was conducted in South Australia to examine the relationship between juvenile lodging (lodging prior to stem elongation) and ear production in barley. Two levels of nitrogen application and six treatments were used either to prevent or increase juvenile lodging in two cultivars. Applications of 2-chloroethyltrimethylammonium chloride (CCC) at the fourth and sixth leaf stages shortened both pseudostems and leaves, prevented juvenile lodging, and increased the number of ears and the grain yield. CCC did not reduce the mature plant height, but did increase the incidence of Rhynchosporium secalis in one cultivar. Ear numbers were marginally increased by supporting the crop with a wire grid or by defoliating the crop to 20 cm at the fifth leaf stage, but this advantage was nullified by a compensating decrease in the other yield components. Removing up to 4 units of leaf area index at this stage did not reduce the yield. Deliberately lodging the crop before stem elongation had little effect since most of the controls lodged naturally. All treatments became erect during stem elongation, and the plants did not lodge again before maturity. It is concluded that short pseudostems, a maximum leaf length under 30 cm, fewer leaves per culm and a shorter period prior to stem elongation are characters which will reduce the juvenile lodging in barley which occurs when the crop is sown early at high plant densities or is grown at high fertility levels.

scholarly journals Effects of postgrazing residue on morphogenetic and structural characteristics of Tifton 85 pastures

2016 ◽  
Vol 37 (4) ◽  
pp. 2043
Author(s):  
Wilton Ladeira Silva ◽  
Ana Cláudia Ruggieri ◽  
Ricardo Andrade Reis ◽  
Américo Garcia Silva Sobrinho ◽  
Euclides Braga Malheiros
Keyword(s):  
Structural Characteristics ◽  
Stem Elongation ◽  
Light Interception ◽  
Climatic Conditions ◽  
Leaf Length ◽  
Elongation Rate ◽  
Area Index ◽  
Structural Variables ◽  
Senescence Rate ◽  
Leaf Appearance

The ideal time to start grazing is when pastures reach 95% light interception. The use of residual leaf area index (rLAI) to time the interruption of grazing under intermittent grazing has recently been studied in forage species in different climatic conditions in Brazil. However, studies evaluating the formation and development of leaves and tillers through morphogenetic and structural variables in functional rLAI are still lacking for Tifton 85 pastures. Therefore, the objective of this study was to evaluate the effects of varying rLAI in successive grazing cycles on morphogenetic and structural characteristics of Tifton 85 pasture grazed intermittently by sheep. Morphogenetic and structural characteristics were evaluated in three grazing cycles under three rLAI conditions (0.8, 1.6, and 2.4). The regrowth interval (time taken to return to 95% light interception) of pastures increased from 21.33 to 29.66 days with decreasing rLAI. The leaf appearance rate increased at a rate of 0.02 leaves tiller-1 day-1 and the number of live leaves per tiller increased by 0.41 with decreasing rLAI. Phyllochron, leaf elongation rate, final leaf length, leaf senescence rate, and stem elongation rate decreased linearly with decreasing rLAI. The number of live leaves per tiller was lower (7.97) in the third grazing cycle, probably owing to the higher senescence rate observed that same cycle, while the other variables had higher values. The 2.4 rLAI condition promotes excessive stem elongation, reduced leaf appearance, lower number of live leaves per tiller, and increased senescence of leaves, while the 0.8 and 1.6 rLAI conditions promote desirable morphogenetic and structural characteristics, which correlate directly with forage quality. In order to avoid excessive forage losses, grazing must occur preferentially by the end of March, when climatic conditions still support the appropriate development of the plants.

scholarly journals Evaluating the effect of plant population densities and nitrogen application on the leaf area index of maize in a reclaimed wetland in Kenya

2016 ◽  
Vol 8 (1) ◽  
pp. 139-148 ◽  
Author(s):  
Catherine Waithira Njuguna ◽  
Hellen Wangechi Kamiri ◽  
John Robert Okalebo ◽  
Wilson Ngetich ◽  
Syphilline Kebeney
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Plant Density ◽  
Block Design ◽  
Nitrogen Application ◽  
Maize Production ◽  
Area Index ◽  
High Plant Density ◽  
Plant Densities ◽  
Set Up

Abstract Maize is the main staple food in Kenya with over 90% of Kenyans relying on it. While the annual national consumption is increasing, the production of this crop has been on the decline in the last two decades. Maize production in Kenya fell by 33.4% in 2013 with Nyeri among the counties said to be grappling with the production of this crop. Land pressure is one of the major causes of decreased availability of food as well as soil depletion and encroachment upon fragile ecosystems such as wetlands. Nitrogen is a key nutrient in the production of maize, and its deficiency is a major factor limiting its production. This study investigated the effect of N application at 120 kg N/ha and maize density on the Leaf Area Index in reclaimed wetland soils in an experimental set-up comprising a randomized complete block design with three replications. The research was carried out in Nyeri County, Kenya. Leaf Area Index (LAI) was determined using the given SunScan formula. Measurements were done continuously until crop physiological maturity. Results indicated that the leaf area index increased with nitrogen application and reduced with spacing for most treatments. There were no significant differences between the two methods (Copy Method and SunScan). Leaf Area Index (LAI) was high in treatments containing nitrogen and high plant density. It was concluded that high plant density gives high LAI. 50 cm * 12.5 cm (-N) and 50 cm * 12.5 cm (+N) are the recommended plant densities for the site.

scholarly journals Effects of Plant Density and Row Spacing on Yield and Yield Components of Peanut (Arachis hypogaea L.) on the Coastal Sandy Land Area in Nghe An Province, Vietnam

2021 ◽  
Author(s):  
Tran Xuan Minh ◽  
Nguyen Cong Thanh ◽  
Tran Hau Thin ◽  
Nguyen Thi Tieng ◽  
Nguyen Thi Huong Giang
Keyword(s):  
Yield Components ◽  
Management Practices ◽  
Plant Density ◽  
Block Design ◽  
Row Spacing ◽  
Sandy Land ◽  
Land Area ◽  
Area Index ◽  
Yield And Yield Components ◽  
Plant Densities

Background: Understanding the effects of different plant densities and row spacing on yield and yield components of peanut L14 is essential for designing and adjusting management practices to improve yield. Methods: Five planting densities were tested in Randomized Complete Block Design with three replications in 2019 spring crop on the coastal sandy land area in Dien Chau district, Nghe An, Vietnam. Result: The different density treatments affect the growth, development and yield of the peanut variety L14. With increasing plant density, the number of pod per plant, 100 pods weight, 100 seeds weight decreased, whereas plant height, leaf area index, dry matter production increased. Population yield increased with increasing plant density from the lowest density of 25 plants m-2 (2.78 tons ha-1), reached the highest at 35 plants m-2 (4.53 tons ha-1), then decreasing with increasing plant density. Peanut variety L14 is grown in plant densities and row spacing of 35 plants m-2 (25 cm × 25 cm) and 40 plants m-2 (25 cm × 20 cm) are most appropriate; plants grow, develop better and give a higher yield than other densities under the same conditions.

The relationship between productivity and some components of canopy structure in ryegrass (Lolium spp.)

1969 ◽  
Vol 73 (3) ◽  
pp. 315-319 ◽  
Author(s):  
Ian Rhodes
Keyword(s):  
Perennial Ryegrass ◽  
Natural Populations ◽  
Canopy Structure ◽  
Leaf Length ◽  
Population Differences ◽  
Base Population ◽  
Potential Production ◽  
Physiological Basis ◽  
Area Index ◽  
The Relationship

SummaryTwo experiments are described in which the potential production of genotypes selected from within S. 321 perennial ryegrass for differing leaf length was assessed (a) in micro-swards composed of populations of similar genotypes and (b) in micro-swards of individual genotypes. In Experiment 1 the long- and short-leaved populations were also compared with the base population of S. 321 and with several other natural populations and bred varieties.Under infrequent cutting the population of long-leaved genotypes was more productive than the short-leaved and base populations. Under frequent cutting, however, the population of short-leaved genotypes was most productive. Similarly, whilst Ba 6280 ryegrass was highly productive and the natural Ynyslas population unproductive under infrequent cutting the situation was reversed under frequent cutting. The population of long-leaved genotypes and Ba 6280 had a higher leaf area index (L) than other populations and varieties at complete light interception.Considerable differences in productivity existed between individual genotypes, and there was also an interaction between genotypes and cutting frequencies. The relationships between yield and both leaf length and chlorophyll content are presented and the physiological basis of inter-genotypic and inter-population differences in production are discussed.

scholarly journals Effect of variety and plant spacing on yield components of two sorghum varieties (Sorghum bicolor l. Moench)

2021 ◽  
Vol 48 (1) ◽  
pp. 175-184
Author(s):  
T. Zakka ◽  
M. R. Hassan ◽  
R. J. Tanko ◽  
B. M. Munza ◽  
A. A. Sadiq
Keyword(s):  
Sorghum Bicolor ◽  
Leaf Area Index ◽  
Leaf Area ◽  
Yield Components ◽  
Leaf Length ◽  
Forage Yield ◽  
Plant Spacing ◽  
Area Index ◽  
Sorghum Variety ◽  
Sorghum Bicolor L

The study was conducted to evaluate the effects of variety, plant spacing and stage of harvest on the forage yield components of two sorghum varieties (Sorghum bicolor L. Moench) at the National Animal Production Research Institute Shika, Zaria. The agronomic study was laid in a 2 × 3 × 5 factorial arrangement of a Split Plot Design with three replicates, which consist of two varieties (bush head and sweet sorghums), three plant spacing (15 × 85, 20 × 85 and 25 × 85 cm) and five stages of harvest (6, 8, 10, 12 and 14 weeks after sowing), respectively. The forage yield was determined at 14 weeks after sowing (WAS). Leaf length (68.68 cm), stem diameter (7.13 cm), number of leaves per plant (12.02) and leaf area index (2.78) were significantly (p<0.05) higher in bush head sorghum variety. Similarly, plant spacing significantly (p<0.05) affected the leaf area index (LAI) with the highest leaf area index recorded in 15 × 85 cm plant spacing. There was significant (p<0.05) interaction between variety and plant spacing. Stage of harvest significantly (p<0.05) affected all the growth parameters with 14 weeks having the highest (223.88 cm) plant height and 10.37 number of leaves per plant and the stage of harvest at 12 weeks after sowing (WAS) recorded the highest 69.84 cm leaf length, 6.82 cm leaf width and 2.46 leaf area index. While stage of harvest at 6 and 10 weeks after sowing (WAS) also having the highest number of tillers per plant and stem diameter of 1.24 and 6.47 cm respectively. Fresh forage yield was significantly (p<0.05) higher (42.92 t/ha) in bush head sorghum variety not and plant spacing significantly (p<0.05) affected fresh forage and dry matter yields at 14 weeks after sowing (WAS). The highest fresh forage yield (41.81 t/ha) and dry matter yield (7.99 t/ha) were recorded in 15 × 85 cm plant spacing. It was concluded, that harvesting of Sorghum bicolor bush head and sweet sorghum varieties for forage is to be best carried out at 14 weeks after sowing for better forage productivity.      L'étude a été menée pour évaluer les effets de la variété de sorgho, et faisant l'espace des plantes sur les composantes de rendement fourrage de deux variétés de sorgho (Sorgho bicolore L. Moench) à l'Institut National de Recherche sur la Production Animale Shika, Zaria. L'étude agronomique a été posée dans un 2 × 3 × 5 arrangement factorial d'une conception de parcelle divisée avec trois répliques, qui se composent de deux variétés (leEffect of variety and plant spacing on yield components of two sorghum varieties (Sorghum bicolor l. Moench)'bush head' et sorghos sucrés), de trois espacements végétaux (15 × 85, 20 × 85 et 25 × 85 cm) et de cinq étapes de récolte (6, 8, 10, 12 et 14 semaines après le semailles), respectivement. Le rendement du fourrage a été déterminé à 14 semaines après la semailles (le 'WAS'). La longueur des feuilles (68,68 cm), le diamètre de la tige (7,13 cm), le nombre de feuilles par plante (12,02) et l'indice de la superficie des feuilles (2,78) étaient significativement (p<0,05) plus élevés dans la variété de sorgho 'bush head'. De même, l'espacement des plantes de façon significative (p<0,05) a affecté l'indice de la superficie des feuilles (le 'LAI') avec l'indice de superficie folio-feuille le plus élevé enregistré en 15 × espacement des plantes de 85 cm. Il y avait une interaction significative (p<0,05) entre la variété et l'espacement des plantes. L'étape de la récolte a eu une incidence importante (p<0,05) sur tous les paramètres de croissance, 14 semaines ayant la hauteur végétale la plus élevée (223,88 cm) et 10,37 le nombre de feuilles par plante et le stade de la récolte à 12 semaines après le semis (WAS) ayant enregistré la longueur de feuilles la plus élevée de 69,84 cm, la largeur des feuilles de 6,82 cm et l'indice de la superficie des feuilles de 2,46 feuilles. Alors que le stade de la récolte à 6 et 10 semaines après le semailles (le 'WAS') a également le plus grand nombre de laboureurs par plante et le diamètre de la tige de 1,24 et 6,47 cm respectivement. Le rendement des fourrages frais était significativement (p<0,05) plus élevé (42,92 t/ha) dans la variété de sorgho de la tête de brousse et l'espacement des plantes de façon significative (p<0,05) affectait les rendements de fourrage frais et de matière sèche à 14 semaines après le semis (le 'WAS'). Le rendement le plus élevé en fourrage frais (41,81 t/ha) et en matière sèche (7,99 t/ha) a été enregistré dans 15 × espacement des plantes de 85 cm. Il a été conclu que la récolte de 'bush head' bicolore de Sorgho et des variétés de sorgho sucré pour le fourrage doit être effectuée au mieux 14 semaines après la semailles pour une meilleure productivité fourragère.        

scholarly journals Epidemiology of the Diseases of Wheat under Different Strategies of Supplementary Irrigation

2012 ◽  
Vol 2012 ◽  
pp. 1-11 ◽  
Author(s):  
Roberto P. Marano ◽  
Roxana L. Maumary ◽  
Laura N. Fernandez ◽  
Luis M. Rista
Keyword(s):  
Yield Components ◽  
Disease Burden ◽  
Stem Elongation ◽  
Disease Incidence ◽  
Flag Leaf ◽  
Tan Spot ◽  
Santa Fe ◽  
Area Index ◽  
Septoria Leaf Blotch ◽  
Supplementary Irrigation

Wheat (Triticum aestivumL.) is one of the most important and highly productive crops grown under supplementary irrigation in the central region of Santa Fe. However, its production is limited by the presence of diseases in the main stages for yield definition. The objective of this work was to assess wheat health in response to different supplementary irrigation strategies under greenhouse and field conditions. The field experiment included three treatments: dry (D), controlled deficit irrigation (CDI), and total irrigation (TI) using the central pivot method. Disease incidence from stem elongation and severity in flag leaf and the leaf below the flag leaf were measured. Leaf area index (LAI), harvest index, air biomass, and yield components were determined. In greenhouse the treatments were TI and CDI, with evaluations similar to the field. The major leaf diseases observed were tan spot, leaf rust, and septoria leaf blotch. Significant differences in disease burden, LAI and yield components were observed in the different treatments. Under greenhouse conditions, only tan spot was observed. The results of this study indicated that the application of supplemental irrigation in wheat improved the yield, without increasing the incidence and severity of foliar diseases.

Changes in growth and yield components ofBrassica napusin response toAzotobacterinoculation at different rates of nitrogen application

1994 ◽  
Vol 122 (2) ◽  
pp. 241-247 ◽  
Author(s):  
Prabhjeet Singh ◽  
S. C. Bhargava
Keyword(s):  
Growth Rate ◽  
Brassica Napus ◽  
Yield Components ◽  
Dry Matter ◽  
Azotobacter Chroococcum ◽  
Growth And Yield ◽  
Nitrogen Application ◽  
Area Index ◽  
Crop Growth Rate ◽  
Yield Increase

SUMMARYInoculation ofBrassica napuscv. ISN–129 withAzotobacter chroococcumfollowing the application of different amounts of nitrogen produced the greatest increase in seed yield and total dry matter when no external nitrogen had been applied. The yield increase in response to inoculation could be attributed to a greater number of primary branches and pods, associated with a higher leaf area index, particularly at the pod-filling stage, and a faster crop growth rate.

Polarized microbeam FT-IR analysis of single fibers

1996 ◽  
Vol 54 ◽  
pp. 206-207
Author(s):  
Liling Cho ◽  
David L. Wetzel
Keyword(s):  
Molecular Orientation ◽  
Transition Point ◽  
Polymer Fibers ◽  
Single Fiber ◽  
Wire Grid ◽  
Polyester Fibers ◽  
Ft Ir ◽  
Ir Analysis ◽  
The Relationship ◽  
Wire Grid Polarizer

Polarized infrared microscopy has been used for forensic purposes to differentiate among polymer fibers. Dichroism can be used to compare and discriminate between different polyester fibers, including those composed of polyethylene terephthalate that are frequently encountered during criminal casework. In the fiber manufacturering process, fibers are drawn to develop molecular orientation and crystallinity. Macromolecular chains are oriented with respect to the long axis of the fiber. It is desirable to determine the relationship between the molecular orientation and stretching properties. This is particularly useful on a single fiber basis. Polarized spectroscopic differences observed from a single fiber are proposed to reveal the extent of molecular orientation within that single fiber. In the work presented, we compared the dichroic ratio between unstretched and stretched polyester fibers, and the transition point between the two forms of the same fiber. These techniques were applied to different polyester fibers. A fiber stretching device was fabricated for use on the instrument (IRμs, Spectra-Tech) stage. Tension was applied with a micrometer screw until a “neck” was produced in the stretched fiber. Spectra were obtained from an area of 24×48 μm. A wire-grid polarizer was used between the source and the sample.

DETERMINATION OF THE EFFICIENCY AND EFFICACY OF BIO-CHEMICAL FERTILIZER ON THE SOIL, YIELD AND GROWTH PERFORMANCE OF BLACK PEPPER (Piper nigrum L.)

2015 ◽  
Vol 4 (3) ◽  
pp. 460-468
Author(s):  
Yap Chin Ann
Keyword(s):  
Growth Performance ◽  
Nutrient Management ◽  
High Growth ◽  
Black Pepper ◽  
Chemical Fertilizer ◽  
Piper Nigrum ◽  
High Fertility ◽  
Fertility Level ◽  
Area Index ◽  
K 12

The last nutrient management review of black pepper was done in 1968. There is, therefore, a need to develop new technology to improve pepper production and transfer that technology to production site. This experiment was carried out to study the effect of newly developed biochemical fertilizer on some physiological characteristics, yield and soil fertility of pepper. The treatment consisted of T1 (BS): chemical fertilizer (N:12%, P:12%, K:17%); T2 (BK1): biochemical fertilizer F1 N:15%, P:5%, K:14) and T3 (BK2): biochemical fertilizer F2 (N:13%, P:4%, K:12). The biochemical fertilizer F1 out-yielded chemical and biochemical fertilizer F2 by 75.38% and 16.45% respectively with the higher yield being associated with various phonotypical alterations, which are reported here. Significant measureable changes were observed in physiological processes and plant characteristics, such as large leaf area index, more chlorophyll content and high photosynthesis rate coupled with lower transpiration rate in biochemical fertilizer F1(BK1) treatment compared with other treatment. The high fertility level in biochemical fertilizer F1 and biochemical fertilizer F2 (BK2) reflected the important of organic material in improving soil quality. In conclusion, the achieve high growth performance and yield in pepper, chemical fertilizer alone is insufficient whilst combination of organic and inorganic fertilizer with balance nutrient content gave a significant increase in yield and growth of pepper. 

scholarly journals Optimizing Grain Yield and Water Use Efficiency Based on the Relationship between Leaf Area Index and Evapotranspiration

Agriculture ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 313
Author(s):  
Guoqiang Zhang ◽  
Bo Ming ◽  
Dongping Shen ◽  
Ruizhi Xie ◽  
Peng Hou ◽  
...  
Keyword(s):  
Grain Yield ◽  
Water Use Efficiency ◽  
Leaf Area Index ◽  
Water Use ◽  
Plant Density ◽  
Maize Yield ◽  
Area Index ◽  
Irrigation Level ◽  
Use Efficiency ◽  
The Relationship

Achieving optimal balance between maize yield and water use efficiency is an important challenge for irrigation maize production in arid areas. In this study, we conducted an experiment in Xinjiang China in 2016 and 2017 to quantify the response of maize yield and water use to plant density and irrigation schedules. The treatments included four irrigation levels: 360 (W1), 480 (W2), 600 (W3), and 720 mm (W4), and five plant densities: 7.5 (D1), 9.0 (D2), 10.5 (D3), 12.0 (D4), and 13.5 plants m−2 (D5). The results showed that increasing the plant density and the irrigation level could both significantly increase the leaf area index (LAI). However, LAI expansion significantly increased evapotranspiration (ETa) under irrigation. The combination of irrigation level 600 mm (W3) and plant density 12.0 plants m−2 (D4) produced the highest maize yield (21.0–21.2 t ha−1), ETa (784.1–797.8 mm), and water use efficiency (WUE) (2.64–2.70 kg m−3), with an LAI of 8.5–8.7 at the silking stage. The relationship between LAI and grain yield and evapotranspiration were quantified, and, based on this, the relationship between water use and maize productivity was analyzed. Moreover, the optimal LAI was established to determine the reasonable irrigation level and coordinate the relationship between the increase in grain yield and the decrease in water use efficiency.

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