Canopy Light Interception Conversion in Upright Fruiting Offshoots (UFO) Sweet Cherry Orchard

2014 ◽  
2020 ◽  
Vol 98 (Supplement_2) ◽  
pp. 26-27
Author(s):  
Caroline Chappell ◽  
Landon Marks ◽  
Katie Mason ◽  
Mary K Mullenix ◽  
Sandra L Dillard ◽  
...  

Abstract A 2-yr study was conducted at Black Belt Research and Extension Center in Marion Junction, AL, to evaluate the effect of nitrogen (N) fertilizer application rate on forage production characteristics, nutritive value, and animal performance of beef heifers grazing a mixture of native warm-season grasses (NWSG) including big bluestem, little bluestem, and indiangrass. Six, two-hectare plots were randomly assigned to one of two treatments (0 or 67 kg N ha-1 applied in early April; n = 3 replications per treatment). Paddocks were continuously stocked with four weaned Angus × Simmental beef heifers (initial BW 288 ± 7 kg) from late May/early June through mid-to-late August during 2018 (73 grazing d) and 2019 (70 grazing d), respectively. Put-and-take cattle were used to manage forage to a target of 38 cm. Forage mass and canopy heights were collected every two weeks during the trial. Visual ground cover ratings, canopy light interception, and botanical composition were measured at the beginning and end of the trial in each year. Hand-plucked samples were collected every two weeks during the grazing trial to determine forage nutritional value. Data were analyzed using the PROC MIXED procedure in SAS 9.4, and differences were declared significant when P ≤ 0.05. Nitrogen fertilized NWSG had greater crude protein (P < 0.0001), sward heights (P = 0.0003), and canopy light interception at the beginning of the season (P = 0.0049) compared to non-fertilized paddocks. However, there were no differences (P ≥ 0.05) among N-fertility treatments for mean forage mass, heifer ADG, or BCS across the 2-yr study. Botanical composition data indicated that indiangrass decreased from 64% to 61% (P = 0.0022) and weed pressure increased from 11% to 15% (P = 0.0064) across the summer grazing season. Canopy light interception decreased by 51% from early June to August in fertilized NWSG and 26% in unfertilized paddocks, respectively. These data illustrate that NWSG systems may provide a viable grazing system in the summer months under reduced N inputs.


2012 ◽  
Author(s):  
Jingjin Zhang ◽  
Ruilong Luo ◽  
Patrick Scharf ◽  
Matthew Whiting ◽  
Qin Zhang

2012 ◽  
Vol 47 (6) ◽  
pp. 863-868 ◽  
Author(s):  
Marcolino Frederico Miguel ◽  
Henrique Mendonça Nunes Ribeiro Filho ◽  
Steben Crestani ◽  
Fabiana da Rocha Ramos ◽  
Tereza Cristina Moraes Genro

The objective of this work was to assess the effects of the sward structure of Italian ryegrass (Lolium multiflorum), during the first grazing cycle, on its morphological and bromatological characteristics throughout the growing season, and on the performance of dairy cows. The treatments consisted of two structures obtained as a function of canopy-light interception: high-light interception (HLI) and low-light interception (LLI), with different pre-grazing heights in the first grazing cycle. Pasture was managed under rotational grazing with a herbage allowance not below 30 kg dry matter (DM) per cow per day. Three grazing cycles, with a grazing interval of 30 days, were evaluated. Pre-grazing herbage mass was greater (2,240 vs. 1,656 kg ha-1 DM), but the proportion of leaf blades was smaller (0.35 vs. 0.43) for HLI swards. Neutral detergent fiber (NDF) content and organic matter digestibility (OMD) were similar between treatments in the first grazing cycle, but in the second and third ones NDF was greater, and OMD lower, for the HLI swards. Milk yields were greater for cows grazing LLI swards (19.4 vs. 21.1 kg per day). Initial grazing with 90% of light interception promotes greater nutritional value in the subsequent cycles.


2016 ◽  
Vol 46 (7) ◽  
pp. 968-977 ◽  
Author(s):  
Gauthier Ligot ◽  
Aitor Ameztegui ◽  
Benoît Courbaud ◽  
Lluís Coll ◽  
Dan Kneeshaw

Mixed and multi-layered forest ecosystems are sometimes more productive than monospecific and single-layered ones. It has been suggested that trees of different species and sizes occupy complementary positions in space, which would act as a mechanism to increase canopy light interception and wood production. However, greater canopy light interception reduces the average amount and variability of transmitted radiation, offering fewer opportunities for all species to regenerate and to maintain forest heterogeneity in the long run. We investigated whether increasing overstory heterogeneity indeed results in greater canopy light interception and lower variability in transmittance. We modeled the three-dimensional structure of forest stands with three typical forest structures, 10 mixtures of four tree species, and three different basal areas. We used the forest light interception model SamsaraLight and performed three-way analyses of covariance to analyze the effects of the three varied components of forest heterogeneity. We found no evidence that increasing structural heterogeneity increases canopy light interception. However, the light interception by mixed canopies was greater than the weighted average of light interception by the corresponding pure canopies. Variability in transmittance increased in some cases with compositional heterogeneity and, to a lesser extent, with tree size inequalities. The advantage of heterogeneous forests is in opportunities for natural regeneration, as well as in opportunities to enhance canopy light interception.


1999 ◽  
Vol 24 (3) ◽  
pp. 271-280 ◽  
Author(s):  
M.A. Dixon ◽  
B. Grodzinski ◽  
R. Côté ◽  
M. Stasiak

2012 ◽  
pp. 251-257 ◽  
Author(s):  
A. Juhász ◽  
P. Sepsi ◽  
K. Tőkei ◽  
L. Hrotkó

AGROFOR ◽  
2016 ◽  
Vol 1 (1) ◽  
Author(s):  
Sanja Lazić ◽  
Dragana Šunjka ◽  
Srđan Panić ◽  
Zdravko Bjelica ◽  
Slavica Vuković

A neonicotinoid insecticide acetamiprid and dicarboximide fungicide iprodione,are used in sweet cherry for control of the major pest (Rhagoletis cerasi L.) andpathogen (Monilia laxa). For the purpose of the safe consumption of agriculturalproducts after pesticide application, studies on their dissipation kinetics areessential to work out their half-lives (DT50) and pre-harvest intervals (PHI).However, there is a lack of information on the persistence of acetamiprid andiprodione in sweet cherry fruits in different climatic conditions of production.Therefore, the objectives of this study were to investigate the dissipation andresidues of acetamiprid and iprodione in sweet cherry fruits, as well as to evaluatethe validity of prescribed PHI for these pesticides. Field experiments wereconducted in a sweet cherry orchard, near Novi Sad, where acetamiprid andiprodione were applied at a recommended concentration. At various time intervals,from treatment to harvest, having in mind PHI (14 days for acetamiprid and 7 daysfor iprodione) representative samples of sweet cherry fruits were collected.Extraction of pesticides was carried out by QuEChERS method, followed byHPLC-DAD analysis. The method was validated in accordance with theSANCO/12571/2013 document and was used the determination of pesticides inreal sweet cherry samples. During the study period, the concentration ofacetamiprid and iprodione decreased from 0.52 mg/kg to 0.11 mg/kg and from 0.29mg/kg to 0.07 mg/kg, respectively. The dissipation of acetamiprid and iprodioneresidues over the time fitted to the equation Ct=0.52-0.22t and Ct=0.29-0.20t, with DT50of 3.15 and 3.47 days, respectively. Finally, the content of acetamiprid andiprodione in sweet cherry samples, at the end of PHI, were below the maximumallowed level specified by the Serbian (1.5 mg/kg and 3 mg/kg) and EU MRLs (1.5mg/kg and 10 mg/kg).


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