scholarly journals Assessment of UAV-Onboard Multispectral Sensor for Non-Destructive Site-Specific Rapeseed Crop Phenotype Variable at Different Phenological Stages and Resolutions

2020 ◽  
Vol 12 (3) ◽  
pp. 397 ◽  
Author(s):  
Sadeed Hussain ◽  
Kaixiu Gao ◽  
Mairaj Din ◽  
Yongkang Gao ◽  
Zhihua Shi ◽  
...  
Keyword(s):  
Leaf Area ◽  
Polynomial Regression ◽  
Dry Weight ◽  
Empirical Method ◽  
Coefficient Of Determination ◽  
Leaf Mass Per Area ◽  
Growth Stages ◽  
Area Index ◽  
Non Destructive ◽  
Different Growth Stages

Unmanned aerial vehicles (UAVs) equipped with spectral sensors have become useful in the fast and non-destructive assessment of crop growth, endurance and resource dynamics. This study is intended to inspect the capabilities of UAV-onboard multispectral sensors for non-destructive phenotype variables, including leaf area index (LAI), leaf mass per area (LMA) and specific leaf area (SLA) of rapeseed oil at different growth stages. In addition, the raw image data with high ground resolution (20 cm) were resampled to 30, 50 and 100 cm to determine the influence of resolution on the estimation of phenotype variables by using vegetation indices (VIs). Quadratic polynomial regression was applied to the quantitative analysis at different resolutions and growth stages. The coefficient of determination (R2) and root mean square error results indicated the significant accuracy of the LAI estimation, wherein the highest R2 values were attained by RVI = 0.93 and MTVI2 = 0.89 at the elongation stage. The noise equivalent of sensitivity and uncertainty analyses at the different growth stages accounted for the sensitivity of VIs, which revealed the optimal VIs of RVI, MTVI2 and MSAVI in the LAI estimation. LMA and SLA, which showed significant accuracies at (R2 = 0.85, 0.81) and (R2 = 0.85, 0.71), were estimated on the basis of the predicted leaf dry weight and LAI at the elongation and flowering stages, respectively. No significant variations were observed in the measured regression coefficients using different resolution images. Results demonstrated the significant potential of UAV-onboard multispectral sensor and empirical method for the non-destructive retrieval of crop canopy variables.

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 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

An analysis of the factors determining yields in crosses between semi-dwarf and taller wheat varieties

1974 ◽  
Vol 82 (3) ◽  
pp. 483-496 ◽  
Author(s):  
F. G. H. Lupton ◽  
R. H. Oliver ◽  
P. Ruckenbauer
Keyword(s):  
Leaf Area ◽  
Polynomial Regression ◽  
Flag Leaf ◽  
Total Yield ◽  
Dry Weight ◽  
Regression Equations ◽  
Wheat Varieties ◽  
Area Index ◽  
Polynomial Coefficients ◽  
Leaf Area Duration

SUMMARYThe growth and development of two semi-dwarf winter wheat varieties, of two taller varieties, and of random selections from two crosses between semi-dwarf and taller varieties were compared over 2 years. Changes with time of crop dry weight/m2, leaf area index and ear size were expressed as orthogonal polynomial regression coefficients. Significant correlations were obtained between yield, the polynomial coefficients and growth measurements relating to number of tillers and flag leaf area duration, but many of these variables were significantly correlated with each other. Multiple regression equations were therefore calculated expressing yield in terms of the variables. These showed flag leaf area duration and rate of ear growth to be the most important characters determining crop yield. The greatest reduction in total yield variance was obtained by the simultaneous consideration of characters relating to photosynthetic capacity and ear development. The significance of this finding in relation to the relative importance of ‘apos;source’ and ‘sink’ in determining grain yield are discussed.

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.

scholarly journals Impact of post-infiltration soil aeration at different growth stages of sub-surface trickle-irrigated tomato plants

2016 ◽  
Vol 30 (3) ◽  
pp. 331-337 ◽  
Author(s):  
Yuan Li ◽  
Zong-xia Jia ◽  
Wen-Quan Niu ◽  
Jing-wei Wang
Keyword(s):  
Growth Period ◽  
Dry Weight ◽  
Growth And Yield ◽  
Growth Stages ◽  
Area Index ◽  
Tomato Plants ◽  
Soil Aeration ◽  
Positive Effects ◽  
High Level ◽  
Different Growth Stages

Abstract Sensitivity to low rhizosphere soil aeration may change over time and therefore plant response may also depend on different growth stages of a crop. This study quantified effects of soil aeration during 5 different periods, on growth and yield of trickle-irrigated potted single tomato plants. Irrigation levels were 0.6 to 0.7 (low level) or 0.7 to 0.8 (high level) of total water holding capacity of the pots. Soil was aerated by injecting 2.5 l of air into each pot through the drip tubing immediately after irrigation. Fresh fruit yield, above ground plant dry weight, plant height, and leaf area index response to these treatments were measured. For all these 4 response variables, means of post-infiltration aeration between 58 to 85 days after sowing were 13.4, 43.5, 13.7, and 37.7% higher than those for the non-aerated pots, respectively. The results indicated that: post-infiltration soil aeration can positively impact the yield and growth of sub-surface trickle-irrigated potted tomato plants; positive effects on plant growth can be obtained with aeration during the whole growth period or with aeration for partial periods; positive growth effects of partial periods of aeration appears to persist and result in yield benefit.

Relations Between Growth Parameters in Oil Palm Seedlings Grown in Polybags

1980 ◽  
Vol 16 (3) ◽  
pp. 275-278 ◽  
Author(s):  
E. O. Lucas
Keyword(s):  
Leaf Area ◽  
Oil Palm ◽  
Growth Parameters ◽  
Weight Ratio ◽  
Dry Weight ◽  
Seedling Height ◽  
Fresh Weight ◽  
Area Index ◽  
Non Destructive ◽  
Selection Of

SUMMARYThe relation between some growth parameters in polybag oil palm nursery seedlings were assessed. ‘Non-destructive’ parameters such as leaf number, seedling height and girth were highly and positively correlated with one another and with the dry weight of seedlings. Amongst the ‘destructive’ parameters only leaf area, height/weight ratio and fresh weight were positively correlated with dry weight. The Leaf Area Index was poorly correlated with other parameters examined. The relevance of these findings to the selection of oil palm seedlings for transplanting into the field is discussed.

scholarly journals Effect of Organic Manures on Growth, Rhizome Yield and Quality Attributes of Turmeric (Curcuma longa L.)

2012 ◽  
Vol 10 (1) ◽  
pp. 16-22 ◽  
Author(s):  
M. Z. U. Kamal ◽  
M. N. Yousuf
Keyword(s):  
Leaf Area ◽  
Dry Matter ◽  
Curcuma Longa ◽  
Dry Weight ◽  
Fresh Weight ◽  
Area Index ◽  
Yield Attributes ◽  
Organic Manures ◽  
Neem Cake ◽  
Yield And Quality

The investigation was carried out to evaluate the effect of different organic manures on turmeric with reference to vegetative growth, biomass production, rhizome yield and its attributes of turmeric (Curcuma longa L.). Turmeric showed better response to the application of organic manures. Plant with neem cake application had the taller plant (79.30 cm), maximum number of tillers per plant (5.40), leaf number (5.40), leaf area (44.09) leaf area index (0.429), fresh weight of halum ( 190.05g), fresh weight of root (49.13 g), fresh weight of rhizome per plant (256.21 g) and dry weight of halum (15.21g), dry weight of root (7.32 g), dry weight of rhizome per plant (40.35 g), total dry matter yield (6.85 t ha-1) than those received other types of manures. Moreover, yield attributes such as number of mother rhizomes per plant-1 (1.75), more number of primary rhizomes per plant-1 (5.19), secondary rhizomes per plant-1 (18.03) and tertiary rhizomes per plant (7.69) were also highly accelerated by neem cake application. Similarly, the same treatment expressed the best in terms of size of mother rhizome (7.69 cm), primary rhizome (21.86 cm) and secondary rhizomes (7.05 cm).All these parameters in cumulative contributed to  produce the highest estimated fresh rhizomes yield & cured rhizomes yield (29.48 t ha-1, 5.59 t ha-1 respectively). The highest curing percentage (20.28) was observed in T3 treatment having mustard cake@ 2.0 t/ha. Thus, organic manure like neem cake was best fitted natural fertilizer for turmeric cultivation.DOI: http://dx.doi.org/10.3329/agric.v10i1.11060The Agriculturists 2012; 10(1): 16-22

Characteristics of the canopy, root system and grain yield of a crop of Lupinus angustifolius cv. Unicrop

1975 ◽  
Vol 26 (3) ◽  
pp. 497 ◽  
Author(s):  
EAN Greenwood ◽  
P Farrington ◽  
JD Beresford
Keyword(s):  
Carbon Dioxide ◽  
Grain Yield ◽  
Leaf Area ◽  
Time Course ◽  
Dry Weight ◽  
Grain Filling ◽  
Main Axis ◽  
Carbon Dioxide Exchange ◽  
Area Index ◽  
Plant Parts

The time course of development of a lupin crop was studied at Bakers Hill, Western Australia. The aim was to gain insight into the crop factors influencing yield. Weekly measurements were made of numbers and weights of plant parts, and profiles of roots, leaf area and light interception. A profile of carbon dioxide in the crop atmosphere was taken at the time of maximum leaf area, and the net carbon dioxide exchange (NCE) of pods was estimated for three successive weeks. The crop took 10 weeks to attain a leaf area index (LAI) of 1 and a further 9 weeks to reach a maximum LAI of 3.75, at which time only 33% of daylight reached the pods on the main axis. Once the maximum LAI was attained at week 19, leaf fall accelerated and rapid grain filling commenced almost simultaneously on all of the three orders of axes which had formed pods. Measurements of NCE between pods on the main axis and the air suggest that the assimilation of external carbon dioxide by the pods contributed little to grain filling. Grain dry weight was 2100 kg ha-1 of which 30%, 60% and 10% came from the main axis, first and second order apical axes respectively. Only 23% of the flowers set pods and this constitutes an important physiological limitation to grain yield.

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