Shoot-to-root ratios and root biomass of cool-season feed crops in a boreal Podzolic soil in Newfoundland

2005 ◽  
Vol 85 (3) ◽  
pp. 369-376 ◽  
Author(s):  
A B Kwabiah ◽  
D. Spaner ◽  
A G Todd

Barley (Hordeum vulgare L.) and oat (Avena sativa L.) crops are grown as feed grains by Newfoundland (NL) dairy farmers. The cereals are either grown as monoculture or intercropped with field pea (Pisum sativum L.) with or without N fertilization. Two experiments were conducted in both 2000 and 2001 to evaluate the shoot-to-root (S:R) weight ratios and root biomass in these production systems. Experiment 1 involved monocultures of pea sown at 150 kg ha-1, and barley and oat each sown at 170 kg ha-1. For pea-barley and pea-oat intercrops, pea was sown at 150 kg ha-1 and each cereal component was sown at either 85 and 170 kg ha-1. The seven treatments were referred to, respectively, as pea150, barley170, oat170, pea150-barley85, pea150-oat85, pea150-barley170, and pea150-oat170. Experiment 2 evaluated factorial combinations of two barley seeding rates of 107 kg ha-1 (low) and 157 kg ha-1 (high) and three N rates (0, 30 and 60 kg ha-1) applied at Zadok’s Growth Stage (ZGS 30). Root biomass was sampled from soil (30-cm depth) and determined at about the anthesis stage of oat and barley and the shoot biomass at maturity (ZGS 90). In exp.1, the S:R ratios of oat170 and pea150-oat85and pea150-oat170 ranged from 8.1 to 8.8 and were lower than barley170, pea150, pea150-barley85and pea150-barley170 which ranged from 10.0 to 12.5. Barley170 had the highest root biomass of 835 kg ha-1 followed by pea150-barley170 (745 kg ha-1) and pea150-oat170 (765 kg ha-1). Intercropping pea with cereals increased root biomas s by 31% for pea150-barley85and 48% for pea150-oat85compared to pea150. However, root biomass increased by 109% for pea150-barley170 and 104% for pea150-oat170, indicating that the cereal component of the intercrops contributed more to the root biomass than the pea at the higher seeding rate of the cereal crop. In exp. 2, the 0 kg N ha-1 rate produced the lowest S:R ratios irrespective of the barley seeding rate. When N was applied, both the shoot biomass and root biomass appeared to be increased at the high barley seeding rate. The feed grain production practice in Newfoundland could affect root biomass production in soil. High cereal seeding rates in either monoculture and intercrop systems are required to maximize root biomass production and therefore increase C inputs into the soil. Key words: Shoot-to-root (S:R) ratios, root biomass, intercrops, barley, oat, pea, seeding rate

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Md. Salim Azad ◽  
Md. Mehedi Hasan Sumon

Nodulation responses of leguminous trees are very important for intercropping to reduce reliance on artificial nitrogen input through nitrogen fixation in agroforestry system. This study was carried out to evaluate the status of nodulation (i.e., the number of nodules and their shape and size) in root and biomass production of plant growth parameters (i.e., number of leaves, shoot height, root biomass, and shoot biomass) of A. auriculiformis seedlings. The assessment was conducted 60 days after seed germination. The study revealed significant differences in nodule number per seedling, leaf number per seedling, shoot height, and biomass accumulation (both green and oven dry weight) with seedling age (p<0.05). The study also revealed significant correlation among the variables of nodulation responses and biomass production. The results obtained using principal component analysis (PCA) justified correlation matrix of nodulation responses and biomass production of this species. The PCA showed that root biomass per seedling, leaf number per seedling, nodule number per seedling, shoot height, age of seedling, and shoot biomass per seedling were clustered with PC1 (with an eigenvalue of 5.59) and root shoot ratios were clustered with PC2 (with an eigenvalue of 1.82). Our study justified that shoot height may be an important determinant of nodule formation of A. auriculiformis.


2015 ◽  
Vol 95 (5) ◽  
pp. 831-839 ◽  
Author(s):  
J. T. O'Donovan ◽  
Y. Anbessa ◽  
C. A. Grant ◽  
A. L. Macleod ◽  
M. J. Edney ◽  
...  

O'Donovan, J. T., Anbessa, Y., Grant, C. A., Macleod, A. L., Edney, M. J., Izydorczyk, M. S., Turkington, T. K., Juskiw, P. E., Lafond, G. P., May, W. E., Harker, K. N., Johnson, E. N., Beres, B. L., McAllister, T. A., Smith, E. G. and Chapman, W. 2015. Relative responses of new malting barley cultivars to increasing nitrogen rates in western Canada. Can. J. Plant Sci. 95: 831–839. Only about 25% of barley (Hordeum vulgare L.) is selected for malting annually in western Canada due to quality issues. While nitrogen (N) fertilization can increase yield, it can also impair quality by increasing protein to unacceptable levels. The objective of this study was to determine the responses of relatively new malting barley cultivars (Bentley, Major, CDC Meredith, and Merit 57) to increasing N rates compared to the response of AC Metcalfe, the most commonly grown malting cultivar. Experiments were conducted at seven locations in western Canada in 2010, 2011 and 2012. Nitrogen was banded at seeding at 0, 30, 60, 90, or 120 kg ha−1. All the new varieties produced higher yield (5 to 11%) than AC Metcalfe. Barley kernel yield and protein concentration increased with N rate. However, Merit 57, CDC Meredith and Bentley produced significantly lower protein concentration in response to N than AC Metcalfe and Major. The newer cultivars displayed higher N utilization efficiency than AC Metcalfe, possibly due to partitioning proportionally more N into leaf chlorophyll development. The higher leaf chlorophyll content may have enabled increased photosynthesis and a more efficient utilization of N for grain formation. Bentley produced the least tillers and had the highest kernel plumpness, while Merit 57 had the lowest kernel plumpness. CDC Meredith lodged most followed by Merit 57, while Major and Bentley lodged least, especially at the higher N rates. Merit 57 and CDC Meredith took longer to mature than the other cultivars but yielded well at relatively short growing season locations.


2008 ◽  
Vol 59 (2) ◽  
pp. 157 ◽  
Author(s):  
Mingtan Liao ◽  
Peter J. Hocking ◽  
Bei Dong ◽  
Emmanuel Delhaize ◽  
Alan E Richardson ◽  
...  

Seedlings from 198 wheat genotypes were screened in glasshouse trials for early biomass production (49 days after sowing, DAS) in a soil high in total phosphorus (P) but low in plant-available P. Fifteen hexaploid bread wheats were then examined more closely for early biomass production on 2 low-P soils: a highly P-fixing Ferrosol (1.3 mg resin-extractable P/kg) and a Red Kandosol (5.2 mg resin-extractable P/kg). The soils were either unamended for P or supplemented with sufficient P for maximum growth. Single lines of rye, triticale, and durum wheat were included for comparison. The plants were harvested at 21 and 35 DAS, and shoot biomass, root biomass, P content, and root length were measured. Shoot biomass was correlated with the P content of the seed in both unamended soils at the first harvest but only in the Ferrosol at the second harvest. There were no correlations between seed P and shoot biomass in the high-P treatments at either harvest. Genotypes were compared with one another by plotting shoot biomass from the high-P treatment against shoot biomass from the low-P treatment. Phosphorus-efficient genotypes were defined as those with relatively greater biomass at low P, while genotypes with a high biomass potential were defined as those able to accumulate relatively more biomass at high P. Two hexaploid wheats, Kukri and Vigour 18, were ranked as being P-efficient genotypes with a high biomass potential on both soils, while Halberd, CD87, and Katepwa were P-inefficient on both soils. Biomass accumulation for each genotype was compared with their root biomass, root : shoot ratio, specific root length and P-uptake efficiency. The strongest correlation across all treatments occurred between shoot biomass and root biomass. We discuss factors that may contribute to the variation in P-uptake efficiency among the genotypes.


PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e12107
Author(s):  
Wenfeng Hou ◽  
Juan Shen ◽  
Weitao Xu ◽  
Muhammad Rizwan Khan ◽  
Yin Wang ◽  
...  

Modern rice production systems need a reliable, easy-to-use, efficient, and environmentally-friendly method to determine plant nitrogen (N) status , predict grain yield, and optimize N management. We conducted field experiments to determine the influence of different N rates on Soil Plant Analysis Development (SPAD) readings of rice leaves. We also performed field validations to evaluate the grain yield and N use efficiency under recommended N rates. Our results showed that leaf SPAD readings increased as N rates increased. We applied the recommended N based on the relationships between the N rates and leaf SPAD readings at the tillering and booting stages. The recommended N decreased N rates and improved N use efficiency without sacrificing grain yield. When compared to farmer practices (FP), the recommended N rates of optimization (OPT) decreased by 5.8% and 10.0%, respectively. In comparison with FP, the N agronomic efficiency of OPT increased by 5.8 and 10.0% while the partial factor productivity of N increased by 6.0 and 14.2%, respectively. The SPAD meter may be a reliable tool to analyze the N in rice, estimate real-time N fertilization, and improve N use efficiency.


Forests ◽  
2020 ◽  
Vol 11 (9) ◽  
pp. 943
Author(s):  
Katri Nissinen ◽  
Virpi Virjamo ◽  
Antti Kilpeläinen ◽  
Veli-Pekka Ikonen ◽  
Laura Pikkarainen ◽  
...  

We studied the growth responses of boreal Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies L. Karst.) and silver birch (Betula pendula Roth) seedlings to simulated climate warming of an average of 1.3 °C over the growing season in a controlled field experiment in central Finland. We had six replicate plots for elevated and ambient temperature for each tree species. The warming treatment lasted for the conifers for three growing seasons and for the birch two growing seasons. We measured the height and diameter growth of all the seedlings weekly during the growing season. The shoot and root biomass and their ratios were measured annually in one-third of seedlings harvested from each plot in autumn. After two growing seasons, the height, diameter and shoot biomass were 45%, 19% and 41% larger in silver birch seedlings under the warming treatment, but the root biomass was clearly less affected. After three growing seasons, the height, diameter, shoot and root biomass were under a warming treatment 39, 47, 189 and 113% greater in Scots pine, but the root:shoot ratio 29% lower, respectively. The corresponding responses of Norway spruce to warming were clearly smaller (e.g., shoot biomass 46% higher under a warming treatment). As a comparison, the relative response of height growth in silver birch was after two growing seasons equal to that measured in Scots pine after three growing seasons. Based on our findings, especially silver birch seedlings, but also Scots pine seedlings benefitted from warming, which should be taken into account in forest regeneration in the future.


2021 ◽  
pp. 1-25
Author(s):  
Mandy Bish ◽  
Brian Dintelmann ◽  
Eric Oseland ◽  
Jacob Vaughn ◽  
Kevin Bradley

Abstract The evolution of herbicide-resistant weeds has resulted in the necessity to integrate non-chemical control methods with chemicals for effective management in crop production systems. In soybean, control of the pigweed species, particularly herbicide-resistant waterhemp and Palmer amaranth, have become predominant concerns. Cereal rye planted as a winter cover crop can effectively suppress early-season weed emergence in soybean, including waterhemp, when planted at a rate of 123 kg ha−1. The objectives of this study were to determine the effects of different cereal rye seeding rates (0, 34, 56, 79, 110, and 123 kg ha−1) on early-season waterhemp suppression and soybean growth and yield. Soybean was planted into fall-seeded cereal rye, which was terminated within four days of soybean planting. The experiment was conducted over the 2018, 2019, and 2020 growing seasons in Columbia, Missouri. Effects of cereal rye on early-season waterhemp suppression varied by year and were most consistent at 56 kg ha−1 or higher seeding rates. Linear regression analysis of cereal rye biomass, height, or stand at soybean planting showed inverse relationships with waterhemp emergence. No adverse effects to soybean growth or yield were observed at any of the cereal rye seeding rates relative to plots that lacked cereal rye cover. Result differences among the years suggest that the successfulness of cereal rye on suppression of early-season waterhemp emergence is likely influenced by the amount of waterhemp seed present in the soil seed bank.


2020 ◽  
Vol 56 (5) ◽  
pp. 767-779
Author(s):  
Juan de Dios García-Villegas ◽  
Anastacio García-Martínez ◽  
Carlos Manuel Arriaga-Jordán ◽  
Monica Elizama Ruiz-Torres ◽  
Adolfo Armando Rayas-Amor ◽  
...  

AbstractThe objective of the study was to characterize small-scale dairy production systems to identify the technological preferences according to the farmer and farm characteristics and to analyze the importance and role of the information communication technologies (ICTs) in the dissemination of information related to management and livestock activities. To collect the data, a survey was applied to 170 small-scale dairy farmers from central Mexico. To characterize the farms, a factor analysis (FA) and cluster analysis (CA) were performed. To compare and identify differences between groups, a Kruskal–Wallis test was conducted. Four factors that explain 70.93% of the accumulated variance were identified; these factors explain the use of technology, production characteristics, social connections, and use of ICTs. The cluster analysis identified four groups. Group 1 was integrated by farmers with more experience and the largest farms. Group 2 had higher studies and use of ICTs. Group 3 was formed by young farmers but had a low use of technology. Group 4 contained older farmers with a low use of technology. The young farmers with higher studies have begun to incorporate ICTs into their daily activities on the farm, as observed in Group 2. Smartphones were the most used and were considered important by the farmers of the four groups, since they enable interaction with other farmers and the dissemination of topics of interest related with the farm. In conclusion, four group of farmers were differentiated; therefore, different extension approaches should be implemented to take into account the preferences and the technologies considered most important for each group. The ICTs are emerging technologies among small-scale dairy farmers to communicate information related to livestock management, mainly by young farmers with studies of secondary, as observed in Group 2.


1990 ◽  
Vol 70 (1) ◽  
pp. 61-69 ◽  
Author(s):  
S. TRAGOONRUNG ◽  
P. M. HAYES ◽  
B. L. JONES

Provided they reliably predict row plot performance, hill plots should be useful for doubled haploid recurrent selection in malting barley (Hordeum vulgare L.). The primary objective of this research was to compare hill and row plot expression of agronomic and malting quality traits in an array of elite spring habit barley germplasm grown under irrigated conditions. A supporting objective was to identify an appropriate seeding rate for hill plot evaluation. Eight-replicate hill plots at four seeding rates (10, 20, 30, and 40 seeds per hill) were compared with adjacent four-replicate row plots in each of three environments. Genotype and genotype × environment interactions were significant for most agronomic traits in both plot types. Significant, linear genotype responses to hill plot seeding rates were observed for most agronomic traits. Seeding rate had no consistent effect on the expression of malting quality. The percentage of lines in common in the two plot types at 25 and 50% selection intensities was the most useful comparison statistic and indicated hill plot selection should be effective for most agronomic and malting quality traits. Although yield heritability estimates were consistently high in both hill and row plots, there was little relationship between trait expression in the two plot types. Differential tillering in response to hill plot competition is likely responsible. A seeding rate of 10 seeds per hill should be appropriate in preliminary screening for traits amenable to hill plot selection in irrigated spring habit malting barley.Key words: Hordeum vulgare L., malting quality, breeding methods, barley


2008 ◽  
Vol 2 (1) ◽  
pp. 16-25 ◽  
Author(s):  
Göran Berndes ◽  
Pål Börjesson ◽  
Madelene Ostwald ◽  
Matilda Palm

2021 ◽  
Author(s):  
Mekides Woldegiorgis Gardi ◽  
Bettina I.G Haussmann ◽  
Waqas Ahmed Malik ◽  
Petra Högy

Abstract AimsThe general aim of this meta-analysis is to synthesize and summarise the mean response of barley yield variables to elevated CO2 (eCO2) and its interaction with temperature and N fertilization. Methods The present study quantitatively synthesized the response of barley to eCO2 and its interaction with temperature, and Nitrogen (N). A meta-analysis procedure was used to analyse five yield variables of barley extracted from 76 articles to determine the effect size and the magnitude in relation to eCO2 and its interaction with temperature and N. Results CO2 enrichment increased biomass (23.8%), grain number (24.8%), grain yield (27.4%), and thousand-grain weight (5.6%). However, responses to eCO2 were affected by genotype, additional stress, and experimental conditions. In comparison, genotype “Anakin” shows the highest response of biomass (47.1%), while “Genebank accessions” had a higher grain number (46.1%) and grain yield (57.1%) under eCO2. The maximal enhancement of barley yield was observed when plants grow under a combination of eCO2 and higher nitrogen fertilizer (>100 kg ha-1). Nevertheless, biomass (-12%), and grain yield (-17%) responses were lower when eCO2 is combined with high temperature (>25 °C). It was further noted the response of barley yield to eCO2 was higher in the growth chamber than in other CO2 exposure methods. Moreover, comparing pot-rooted versus field-rooted barley plants, a higher response of biomass and grain yield was observed for pot-rooted plants. ConclusionsOverall, results suggest that the maximal barley production under eCO2 will be obtained in combination with high nitrogen fertilizer and optimal temperature (21-25 °C).


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