scholarly journals The structure of the weed and seed productivity of weeds in plantings of willow energy

Author(s):  
Y.Р. Makukh

The structure of the weed and seed productivity of weeds in plantings of willow energy the first year of life. It is established that the greatest number of weed species are presented in families of grass: Graminеае, Chenopodiaceae, Polygonaceae, Solanaceae, Rubiaceae.

2021 ◽  
Vol 901 (1) ◽  
pp. 012046
Author(s):  
A A Ivanova

Abstract The studies were carried out in the Moscow region in 2019-2021. In order to create a new breeding material for creeping hay-pasture clover, samples of the Lodian type (giganteum variety), characterized by high peduncles and longer leaf petioles, and a low content of hydrocyanic acid (0.3 mg%), were selected as parental forms. Reciprocal crossing was carried out. Hybrids F1 and F2 in the first year of life were assessed by the main economic and biological characteristics: the length of the peduncles, the number of inflorescences on the plant, fodder and seed productivity, early maturity, winter hardiness and other indicators. Based on the assessment results, the best hybrids and individual biotypes were identified.


2020 ◽  
pp. 17-20
Author(s):  
S. Remeniuk ◽  
N. Smolkova

Goal. Determination of soil contamination of plots planted for planting black poplar and evaluation of seed productivity of weeds. Methods. The level of seed productivity of the weeds was determined by the weighting method in the following sequence. In the experiment, 10 plants of one weed species were cut and manually threshed on a tarpaulin. The purified seeds were weighed and, after determining the mass of 1000 seeds, the average amount (thousand units /plant) of seeds per plant was converted. Results. The problem with perennial plantations of bioenergy crops is that the plants are grown for 10—15 years in monoculture on the same section of the field. Consequently, large stocks of certain weeds in the soil can significantly affect the growth and development and productivity level of cultivated plants. So, before planting a plantation, it is necessary to assess the clogging of the plots for the presence of problematic weed species, which can potentially breed on black poplar plantings and impede effective plant care. Virtually all arable land is mothballed with a different weed seed bank. Weed seed stocks depend on the direction of use of the plot, the culture of agriculture, the quality of agricultural operations on care, crop rotation, culture, etc. However, two areas with the same seed reserves in the soil are difficult to find, although the percentage of the main weed species may be identical. Conclusions. Weeds traditionally have high seed productivity and form large seed banks in the arable soil, reaching 1.5—2.0 million units / ha. Bioenergy crops, especially perennial species, are extremely sensitive to weeds in the first year of growing season. Because they form rather modest growths of vegetative mass and can not receive photosynthetically active energy to the soil, and therefore it is important to ensure the purity of the field from weeds during the first year of vegetation.


2009 ◽  
Vol 18 (1) ◽  
pp. 19-24
Author(s):  
Maggie-Lee Huckabee

Abstract Research exists that evaluates the mechanics of swallowing respiratory coordination in healthy children and adults as well and individuals with swallowing impairment. The research program summarized in this article represents a systematic examination of swallowing respiratory coordination across the lifespan as a means of behaviorally investigating mechanisms of cortical modulation. Using time-locked recordings of submental surface electromyography, nasal airflow, and thyroid acoustics, three conditions of swallowing were evaluated in 20 adults in a single session and 10 infants in 10 sessions across the first year of life. The three swallowing conditions were selected to represent a continuum of volitional through nonvolitional swallowing control on the basis of a decreasing level of cortical activation. Our primary finding is that, across the lifespan, brainstem control strongly dictates the duration of swallowing apnea and is heavily involved in organizing the integration of swallowing and respiration, even in very early infancy. However, there is evidence that cortical modulation increases across the first 12 months of life to approximate more adult-like patterns of behavior. This modulation influences primarily conditions of volitional swallowing; sleep and naïve swallows appear to not be easily adapted by cortical regulation. Thus, it is attention, not arousal that engages cortical mechanisms.


2001 ◽  
Vol 120 (5) ◽  
pp. A209-A209
Author(s):  
G RIEZZO ◽  
R CASTELLANA ◽  
T DEBELLIS ◽  
F LAFORGIA ◽  
F INDRIO ◽  
...  

2013 ◽  
Author(s):  
Julie Lawrence ◽  
Andrew Gray ◽  
Rachael Taylor ◽  
Barry Taylor

2004 ◽  
Vol 52 (S 1) ◽  
Author(s):  
H G�rler ◽  
A B�ning ◽  
J Scheewe ◽  
J Paulsen ◽  
HH Kramer ◽  
...  

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