scholarly journals Seasonal Variation of the Canopy Structure Parameters and Its Correlation with Yield-Related Traits in Sugarcane

2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Jun Luo ◽  
Youxiong Que ◽  
Hua Zhang ◽  
Liping Xu
Keyword(s):  
Transmission Coefficient ◽  
Canopy Structure ◽  
Diffuse Radiation ◽  
Growth Stages ◽  
Beam Radiation ◽  
Area Index ◽  
Sugarcane Varieties ◽  
Sugarcane Yield ◽  
Leaf Distribution ◽  
Different Growth Stages

Population structure determines sugarcane yield, of which canopy structure is a key component. To fully understand the relations between sugarcane yield and parameters of the canopy structure, 17 sugarcane varieties were investigated at five growth stages. The results indicated that there were significant differences between characterized parameters among sugarcane populations at different growth stages. During sugarcane growth after planting, leaf area index (LAI) and leaf distribution (LD) increased, while transmission coefficient for diffuse radiation (TD), mean foliage inclination angle (MFIA), transmission coefficient for solar beam radiation penetration (TR), and extinction coefficient (K) decreased. Significant negative correlations were found between sugarcane yield and MFIA, TD, TR, andKat the early elongation stage, while a significant positive correlation between sugarcane yield and LD was found at the same stage. A regression for sugarcane yield, with relative error of yield fitting less than 10%, was successfully established: sugarcane yield = 2380.12 + 46.25 × LD − 491.82 × LAI + 1.36 × MFIA + 614.91 × TD − 1908.05 × TR − 182.53 ×  K+ 1281.75 × LD − 1.35 × MFIA + 831.2 × TR − 407.8 ×  K+ 8.21 × MFIA − 834.50 × TD − 1695.49 ×  K  (R2=0.94**).

scholarly journals Photosynthetic and Canopy Characteristics of Different Varieties at the Early Elongation Stage and Their Relationships with the Cane Yield in Sugarcane

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Jun Luo ◽  
Yong-Bao Pan ◽  
Liping Xu ◽  
Yuye Zhang ◽  
Hua Zhang ◽  
...  
Keyword(s):  
Net Photosynthetic Rate ◽  
Transmission Coefficient ◽  
Photosynthetic Rate ◽  
Canopy Structure ◽  
Measuring System ◽  
Cane Yield ◽  
Beam Radiation ◽  
Area Index ◽  
Sugarcane Varieties ◽  
Sugarcane Yield

During sugarcane growth, the Early Elongation stage is critical to cane yield formation. In this study, parameters of 17 sugarcane varieties were determined at the Early Elongation stage using CI-301 photosynthesis measuring system and CI-100 digital plant canopy imager. The data analysis showed highly significant differences in leaf area index (LAI), mean foliage inclination angle (MFIA), transmission coefficient for diffused light penetration (TD), transmission coefficient for solar beam radiation penetration (TR), leaf distribution (LD), net photosynthetic rate (PN), transpiration rate (E), and stomatal conductance (GS) among sugarcane varieties. Based on the photosynthetic or canopy parameters, the 17 sugarcane varieties were classified into four categories. Through the factor analysis, nine parameters were represented by three principal factors, of which the cumulative rate of variance contributions reached 85.77%. A regression for sugarcane yield, with relative error of yield fitting less than 0.05, was successfully established: sugarcane yield = −27.19 − 1.69 × PN + 0.17 ×  E+ 90.43 × LAI − 408.81 × LD + 0.0015 × NSH + 101.38 ×  D(R2=0.928**). This study helps provide a theoretical basis and technical guidance for the screening of new sugarcane varieties with high net photosynthetic rate and ideal canopy structure.

Leaf area durations and grain yields of two tropical rice varieties

1968 ◽  
Vol 8 (34) ◽  
pp. 587
Author(s):  
PC Owen
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Photosynthetic Efficiency ◽  
Temperate Climate ◽  
Growth Stages ◽  
Rice Varieties ◽  
Area Index ◽  
Grain Yields ◽  
Different Growth Stages

A series of differing leaf area index regimes during the growth of two tropical rice varieties was produced by partial defoliation at different growth stages. In addition, part of the crop was completely defoliated after panicle emergence. Comparison of the effects of the range of leaf area durations (D) thus produced showed that these rice varieties differed from temperate climate cereals. Grain yields were least associated with D after panicle emergence, but were most influenced by D before emergence. This effect is mainly via an influence upon the number of spikelets formed per panicle. Grain : leaf ratio, a measure of photosynthetic efficiency, was considerably lower than values reported for wheat.

scholarly journals Stemflow and its controlling factors in the subshrub Artemisia ordosica during two contrasting growth stages in the Mu Us sandy land of northern China

2015 ◽  
Vol 47 (2) ◽  
pp. 409-418 ◽  
Author(s):  
Liu Li ◽  
Xiao-Yan Li ◽  
Si-Yi Zhang ◽  
Zhi-Yun Jiang ◽  
Xiao-Ran Zheng ◽  
...  
Keyword(s):  
Growth Stage ◽  
Canopy Structure ◽  
Northern China ◽  
Growth Stages ◽  
Sandy Land ◽  
Artemisia Ordosica ◽  
Growth Season ◽  
Area Index ◽  
Mu Us Sandy Land ◽  
Canopy Area

The yield of stemflow from vegetation is mostly affected by rainfall and canopy structure, but few past studies have paid attention to the dynamics of canopy structure during the growth season. Artemisia ordosica is a typical subshrub, very different from trees and shrubs. Assessing the influence of canopy structure and rainfall on stemflow yield in A. ordosica during the growth season will fill a knowledge gap in our understanding of stemflow yield from subshrub species. This study therefore examined the effects of those two factors on stemflow at two growth stages of A. ordosica, using 20 experimental individuals in the Mu Us sandy land of northern China. It demonstrated that the mean stemflow percentage of gross rainfall (SF%) for this subshrub was 8.56%, and the average funneling ratio was 75.80. The critical control factors of stemflow volumes were rainfall amount and canopy area, which varied greatly during the growth season. The SF% was significantly lower during the reproductive growth stage than during the vegetative growth stage, because of the rapid increase in leaf area index at the former stage. This evaluation of the effects of vegetation growth dynamics on stemflow yield will improve the accuracy of future hydrological models.

scholarly journals Remote sensing retrieval of winter wheat leaf area index and canopy chlorophyll density at different growth stages

2021 ◽  
pp. 1-23
Author(s):  
Naichen Xing ◽  
Wenjiang Huang ◽  
Huichun Ye ◽  
Yingying Dong ◽  
Weiping Kong ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Winter Wheat ◽  
Leaf Area Index ◽  
Leaf Area ◽  
Growth Stages ◽  
Area Index ◽  
Wheat Leaf ◽  
Different Growth Stages

scholarly journals A Quantitative Monitoring Method for Determining Maize Lodging in Different Growth Stages

2020 ◽  
Vol 12 (19) ◽  
pp. 3149
Author(s):  
HaiXiang Guan ◽  
HuanJun Liu ◽  
XiangTian Meng ◽  
Chong Luo ◽  
YiLin Bao ◽  
...  
Keyword(s):  
Screening Method ◽  
Canopy Structure ◽  
Window Size ◽  
Growth Stages ◽  
Homogeneous Field ◽  
Gray Level ◽  
Monitoring Method ◽  
Feature Sets ◽  
Optimal Window ◽  
Different Growth Stages

Many studies have achieved efficient and accurate methods for identifying crop lodging under homogeneous field surroundings. However, under complex field conditions, such as diverse fertilization methods, different crop growth stages, and various sowing periods, the accuracy of lodging identification must be improved. Therefore, a maize plot featuring different growth stages was selected in this study to explore an applicable and accurate lodging extraction method. Based on the Akaike information criterion (AIC), we propose an effective and rapid feature screening method (AIC method) and compare its performance using indexed methods (i.e., variation coefficient and relative difference). Seven feature sets extracted from unmanned aerial vehicle (UAV) images of lodging and nonlodging maize were established using a canopy height model (CHM) and the multispectral imagery acquired from the UAV. In addition to accuracy parameters (i.e., Kappa coefficient and overall accuracy), the difference index (DI) was applied to search for the optimal window size of texture features. After screening all feature sets by applying the AIC method, binary logistic regression classification (BLRC), maximum likelihood classification (MLC), and random forest classification (RFC) were utilized to discriminate among lodging and nonlodging maize based on the selected features. The results revealed that the optimal window sizes of the gray-level cooccurrence matrix (GLCM) and the gray-level difference histogram statistical (GLDM) texture information were 17 × 17 and 21 × 21, respectively. The AIC method incorporating GLCM texture yielded satisfactory results, obtaining an average accuracy of 82.84% and an average Kappa value of 0.66 and outperforming the index screening method (59.64%, 0.19). Furthermore, the canopy structure feature (CSF) was more beneficial than other features for identifying maize lodging areas at the plot scale. Based on the AIC method, we achieved a positive maize lodging recognition result using the CSFs and BLRC. This study provides a highly robust and novel method for monitoring maize lodging in complicated plot environments.

scholarly journals Phosphorus and Zinc Interaction Influence Leaf Area Index in Fine vs. Coarse Rice (Oryza sativa L) Genotypes in Northwest Pakistan

2016 ◽  
Vol 2 ◽  
Author(s):  
Amanullah , ◽  
Inamullah , ◽  
Zahir Shah ◽  
Shad Khan Khalil
Keyword(s):  
Oryza Sativa ◽  
Leaf Area Index ◽  
Leaf Area ◽  
Growth And Yield ◽  
Growth Stages ◽  
Area Index ◽  
Physiological Maturity ◽  
Rice Genotypes ◽  
The Impact ◽  
Different Growth Stages

Leaf area index (LAI) is a measure of leafiness per unit ground area and denotes the extent of photosynthetic machinery is an important growth and yield-determining factor because it is a major determinant of light interception and transpiration. Phosphorus (P) and zinc (Zn) and rate are the most important factors affecting leaf area index (LAI) of rice(<em>Oryza sativa</em> L.). A field experiment was conducted to assess the impact of phosphorus (0, 40, 80, 120 kg P ha<sup>-1</sup>) and zinc levels (0, 5, 10, 15 kg Zn ha<sup>-1</sup>) on LAI of rice (<em>Oryza sativa</em> L.) genotypes [fine (Basmati-385) and coarse (Fakhr-e-Malakand &amp; Pukhraj)]. The experiment was conducted on farmer field at Batkhela, Malakadnd in Northwest Pakistan during summer 2011 and 2012. When combined over the two years, the data revealed that the highest LAI at three different growth stages (tillering, heading and physiological maturity) was obtained with application of the highest P level (120 kg ha<sup>-1</sup>) being at par with 80 kg P ha<sup>-1</sup>, while the lowest LAI was recorded when P was not applied. Similarly, the highest LAI was obtained with application of the two higher Zn levels (10 and 15 kg Zn ha<sup>-1</sup>), while the lowest LAI was recorded when Zn was not applied. In case of rice genotypes, the highest LAI was obtained from Pukhraj than other two genotypes at all growth stages. The other two rice genotypes (Fakher-e-Malakand and Basmati-385) produced statistically similar LAI at different growth stages. The higher LAI of Pukhraj was attributed to its long and wider leaves that resulted in higher mean single leaf area, leaf area per tiller, per hill and per square meter. The LAI was highest at heading stages than at early (tillering) and later (physiological maturity) growth stages. The increase in LAI was attributed to the increase in tillers number and leaf area hill<sup>-1</sup>. The increase in LAI showed positive impact on crop growth rate, dry matter accumulationand yield. Application of 120 kg P + 10 kg Zn ha<sup>-1</sup> to rice genotype Pukhraj was more beneficial in terms of higher LAI and productivity in the study area.

Characteristics of High Yielding Cassava Varieties

1976 ◽  
Vol 12 (2) ◽  
pp. 135-143 ◽  
Author(s):  
James H. Cock
Keyword(s):  
Canopy Structure ◽  
High Yield ◽  
Root Production ◽  
Growth Stages ◽  
Early Type ◽  
Leaf Production ◽  
Area Index ◽  
Very High ◽  
Better Than ◽  
Cassava Varieties

SUMMARYForty different cultivars of cassava were grown in unreplicated plots at a plant population of 20,000 plants/ha in fertile soil. Harvests were taken at 4, 6, 8, 10 and 12 months after planting 18 varieties. The characteristics of the two highest yielding varieties, M Colombia 113 (66 t/ha) and M Colombia 22 (32 t/ha), were compared with the other types. M Colombia 22 is an early type (25 t/ha after 6 months) with a very high harvest index; M Colombia 113 yields little better than average 6 months after planting. High yield is associated with a balance between leaf production and root production, so that leaf area index does not decline excessively in the later growth stages. Changing canopy structure is unlikely to increase yields.

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