EFFECTS OF PLANTING DENSITY ON CANOPY PHOTOSYNTHESIS, CANOPY STRUCTURE AND YIELD FORMATION OF HIGH-YIELD COTTON IN XINJIANG, CHINA

Thermolysis of [8,8-(PMe2Ph)2-nido-8,7-PtCB9H11] in boiling toluene solution results in an elimination of the platinum centre and cluster closure to give the ten-vertex closo species [6-(PMe2Ph)-closo-1-CB9H9] in 85% yield as a colourles air stable solid. The product is characterized by NMR spectroscopy and single-crystal X-ray diffraction analysis. Crystals (from hexane-dichloromethane) are monoclinic, space group P21/c, with a = 903.20(9), b = 1 481.86(11), c = 2 320.0(2) pm, β = 97.860(7)° and Z = 8, and the structure has been refined to R(Rw) = 0.045(0.051) for 3 281 observed reflections with Fo > 2.0σ(Fo). The clean high-yield elimination of a metal centre from a polyhedral metallaborane or metallaheteroborane species is very rare.

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Responses of Branch Number and Yield Component of Soybean Cultivars Tested in Different Planting Densities

Agriculture ◽

10.3390/agriculture11010069 ◽

2021 ◽

Vol 11 (1) ◽

pp. 69

Author(s):

Cailong Xu ◽

Ruidong Li ◽

Wenwen Song ◽

Tingting Wu ◽

Shi Sun ◽

...

Keyword(s):

Key Management ◽

Management Practices ◽

Yield Component ◽

Planting Density ◽

Yield Potential ◽

High Yield ◽

Branch Number ◽

Soybean Yield ◽

Soybean Cultivars ◽

Pod Number

Increasing planting density is one of the key management practices to enhance soybean yield. A 2-yr field experiment was conducted in 2018 and 2019 including six planting densities and two soybean cultivars to determine the effects of planting density on branch number and yield, and analyze the contribution of branches to yield. The yield of ZZXA12938 was 4389 kg ha−1, which was significantly higher than that of ZH13 (+22.4%). In combination with planting year and cultivar, the soybean yield increased significantly by 16.2%, 31.4%, 41.4%, and 46.7% for every increase in density of 45,000 plants ha−1. Yield will not increase when planting density exceeds 315,000 plants ha−1. A correlation analysis showed that pod number per plant increased with the increased branch number, while pod number per unit area decreased; thus, soybean yield decreased. With the increase of branch number, the branch contribution to yield increased first, and then plateaued. ZH13 could produce a high yield under a lower planting density due to more branches, while ZZXA12938 had a higher yield potential under a higher planting density due to the smaller branch number and higher tolerance to close planting. Therefore, seed yield can be increased by selecting cultivars with a little branching capacity under moderately close planting.

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Dearomatizing Anionic Cyclization and Novel Skeletal Rearrangement: High Yield Formation of Multiply Substituted Bicyclic or Polycyclic Spirocyclopentadienes and Phenanthrene Derivatives from 4-Aryl 1-Lithio-1,3-butadienes

The Journal of Organic Chemistry ◽

10.1021/jo070160u ◽

2007 ◽

Vol 72 (9) ◽

pp. 3484-3491 ◽

Cited By ~ 22

Author(s):

Lantao Liu ◽

Zhihui Wang ◽

Fei Zhao ◽

Zhenfeng Xi

Keyword(s):

High Yield ◽

Skeletal Rearrangement ◽

Yield Formation

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Photosynthetic activity of selected genotypes of hops (Humulus lupulus L.) in critical periods for yield formation

Plant Soil and Environment ◽

10.17221/30/2011-pse ◽

2011 ◽

Vol 57 (No. 6) ◽

pp. 264-270 ◽

Cited By ~ 2

Author(s):

J. Pokorný ◽

J. Pulkrábek ◽

P. Štranc ◽

D. Bečka

Keyword(s):

Photosynthetic Activity ◽

Photosynthesis Rate ◽

High Yield ◽

Critical Periods ◽

Maturity Level ◽

Flowering Stage ◽

Humulus Lupulus L ◽

Similar Chemical ◽

New Varieties ◽

Yield Formation

This paper evaluates the influence of genotype on the photosynthetic activity of hops in the period critical for generating yield. Results over three years from measuring the photosynthesis rate statistically show an increase in the photosynthetic activity of hop plants in the flowering stage. The average photosynthetic rates from measurements on the second date (BBA 65) in the years 2007, 2008, and 2009 increased by 17.9%, 45.6%, and 49.2%, respectively. Different photosynthesis curve trends during the final stage of ontogenesis of the plants indicate the maturity level of each hop genotype. As regards the genotypes for which photosynthesis did not reduce significantly, it may be assumed that such plants had not reached technical maturity. The results from the three-year study also show that any promising genotype, with respect to the photosynthesis rate and yield, is the result of breeding of new varieties with greater resistance to drought and high temperatures. Very good results in photosynthetic activity were reached by the new varieties exhibiting high yield and a similar chemical composition to Saaz hop and those sharing the same origins to Saaz, showing a higher content of bitter substances. In 2008 and 2009, all three new forms reached yield levels of 2.35 to 3.12 t/ha of dry hops.

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Diagnosing the Climatic and Agronomic Dimensions of Rain-Fed Oat Yield Gaps and Their Restrictions in North and Northeast China

Sustainability ◽

10.3390/su11072104 ◽

2019 ◽

Vol 11 (7) ◽

pp. 2104 ◽

Cited By ~ 1

Author(s):

Chong Wang ◽

Jiangang Liu ◽

Shuo Li ◽

Ting Zhang ◽

Xiaoyu Shi ◽

...

Keyword(s):

Northeast China ◽

Crop Production ◽

Crop Yields ◽

Climatic Conditions ◽

Planting Density ◽

Limiting Factors ◽

High Yield ◽

Yield Gap ◽

Potential Yield ◽

Yield Gaps

Confronted with the great challenges of globally growing populations and food shortages, society must achieve future food security by increasing grain output and narrowing the gap between potential yields and farmers’ actual yields. This study attempts to diagnose the climatic and agronomic dimensions of oat yield gaps and further to explore their restrictions. A conceptual framework was put forward to analyze the different dimensions of yield gaps and their limiting factors. We quantified the potential yield (Yp), attainable yield (Yt), experimental yield (Ye), and farmers’ actual yield (Ya) of oat, and evaluated three levels of yield gaps in a rain-fed cropping system in North and Northeast China (NC and NEC, respectively). The results showed that there were great differences in the spatial distributions of the four kinds of yields and three yield gaps. The average yield gap between Yt and Ye (YG-II) was greater than the yield gap between Yp and Yt (YG-I). The yield gap between Ye and Ya (YG-III) was the largest among the three yield gaps at most sites, which indicated that farmers have great potential to increase their crop yields. Due to non-controllable climatic conditions (e.g., light and temperature) for obtaining Yp, reducing YG-I is extremely difficult. Although YG-II could be narrowed through enriching soil nutrients, it is not easy to improve soil quality in the short term. In contrast, narrowing YG-III is the most feasible for farmers by means of introducing high-yield crop varieties and optimizing agronomic managements (e.g., properly adjusting sowing dates and planting density). This study figured out various dimensions of yield gaps and investigated their limiting factors, which should be helpful to increase farmers’ yields and regional crop production, as long as these restrictions are well addressed.

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ChemInform Abstract: Acylation of Pyridine Rings Mediated by Group 4 Metal Aryl Oxide Compounds: High Yield Formation of α,α′-Disubstituted-2,6-pyridinedimethoxide Ligands.

ChemInform ◽

10.1002/chin.199051308 ◽

1990 ◽

Vol 21 (51) ◽

Author(s):

C. H. ZAMBRANO ◽

A. K. MCMULLEN ◽

L. M. KOBRIGER ◽

P. E. FANWICK ◽

I. P. ROTHWELL

Keyword(s):

High Yield ◽

Group 4 ◽

Yield Formation ◽

Group 4 Metal

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High Yield Achieved by Early-Maturing Rapeseed with High Light Energy and Temperature Production Efficiencies under Ideal Planting Density

Crop Science ◽

10.2135/cropsci2018.04.0255 ◽

2019 ◽

Vol 59 (1) ◽

pp. 351-362 ◽

Cited By ~ 2

Author(s):

Zhenghua Xu ◽

Tao Luo ◽

Na Rao ◽

Liang Yang ◽

Jiahuan Liu ◽

...

Keyword(s):

High Light ◽

Light Energy ◽

Planting Density ◽

High Yield ◽

Early Maturing ◽

Production Efficiencies

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Biomass yield and energy efficiency of willow depending on cultivar, harvesting frequency and planting density

Plant Soil and Environment ◽

10.17221/594/2018-pse ◽

2019 ◽

Vol 65 (No. 8) ◽

pp. 377-386 ◽

Cited By ~ 2

Author(s):

Bogdan Kulig ◽

Edward Gacek ◽

Roman Wojciechowski ◽

Andrzej Oleksy ◽

Marek Kołodziejczyk ◽

...

Keyword(s):

Energy Efficiency ◽

Dry Matter ◽

Plant Density ◽

Calorific Value ◽

Dry Weight ◽

Planting Density ◽

High Yield ◽

Full Production ◽

One Year ◽

The One

The study aimed at comparing the yield of dry biomass and energy efficiency of 22 willow cultivars depending on the harvesting frequency and variable plant density. The field experiment was established in 2010. The willow cultivars were planted in two densities; 13 300 and 32 500 plants per ha. Among the compared cultivars in the second year (2013) of full production, high yield of dry matter was obtained from cvs. Tordis (33.1 t/ha/year), Inger (30.4 t/ha/year) and Klara (29.0 t/ha/year). After six years of cultivation, the highest aboveground dry matter was given by cvs. Tora (27.4 t/ha/year) and Tordis (27.0 t/ha/year). The gross calorific value of willow biomass ranged from 15.2–20.1 GJ/t dry weight. Greater energy efficiency (329.3 GJ/ha/year) occurred in willow cultivars collected in a two-year cycle than in the one-year cycle (286.4 GJ/ha/year). In the two-year cycle collected in the third year after planting, energy efficiency was greater (379.5 GJ/ha/year) than in the two-year cycle harvested in the sixth year after planting (279.15 GJ/ha/year). The initial slower growth of biomass does not determine plant yielding.

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