scholarly journals Morphological and Physiological Root Plasticity and Its Relationships with Shoot Growth of Rice with Water Regimes and Microbial Densities

Author(s):  
Abha Mishra
Fruits ◽  
2003 ◽  
Vol 58 (6) ◽  
pp. 345-356
Author(s):  
Edossa Etissa ◽  
Seifu G Mariam ◽  
H. Ravishanker

2016 ◽  
Vol 6 (2) ◽  
pp. 942-952
Author(s):  
Xicun ZHU ◽  
Zhuoyuan WANG ◽  
Lulu GAO ◽  
Gengxing ZHAO ◽  
Ling WANG

The objective of the paper is to explore the best phenophase for estimating the nitrogen contents of apple leaves, to establish the best estimation model of the hyperspectral data at different phenophases. It is to improve the apple trees precise fertilization and production management. The experiments were done in 20 orchards in the field, measured hyperspectral data and nitrogen contents of apple leaves at three phenophases in two years, which were shoot growth phenophase, spring shoots pause growth phenophase, autumn shoots pause growth phenophase. The study analyzed the nitrogen contents of apple leaves with its original spectral and first derivative, screened sensitive wavelengths of each phenophase. The hyperspectral parameters were built with the sensitive wavelengths. Multiple stepwise regressions, partial least squares and BP neural network model were adopted in the study. The results showed that 551 nm, 716 nm, 530 nm, 703 nm; 543 nm, 705 nm, 699 nm, 756 nm and 545 nm, 702 nm, 695 nm, 746 nm were sensitive wavelengths of three phenophases. R551+R716, R551*R716, FDR530+FDR703, FDR530*FDR703; R543+R705, R543*R705, FDR699+FDR756, FDR699*FDR756and R545+R702, R545*R702, FDR695+FDR746, FDR695*FDR746 were the best hyperspectral parameters of each phenophase. Of all the estimation models, the estimated effect of shoot growth phenophase was better than other two phenophases, so shoot growth phenophase was the best phenophase to estimate the nitrogen contents of apple leaves based on hyperspectral models. In the three models, the 4-3-1 BP neural network model of shoot growth phenophase was the best estimation model. The R2 of estimated value and measured value was 0.6307, RE% was 23.37, RMSE was 0.6274.


2018 ◽  
Vol 24 (3) ◽  
pp. 57-63
Author(s):  
In-Kwan Song ◽  
Seong-Bae Kim ◽  
Bo-Hwa Kim ◽  
Jeong-Hee Yoon ◽  
Soon-Young Hong ◽  
...  
Keyword(s):  

2010 ◽  
Vol 36 (11) ◽  
pp. 1832-1842 ◽  
Author(s):  
Bo PENG ◽  
Yang WANG ◽  
Yong-Xiang LI ◽  
Cheng LIU ◽  
Zhi-Zhai LIU ◽  
...  

1999 ◽  
Vol 40 (3) ◽  
pp. 233-240 ◽  
Author(s):  
S. G. T. Giovannini ◽  
D. M. L. da Motta Marques

The behavior of three emergent aquatic macrophytes under different water regimes was studied with the aim of achieving reconvertion of degraded wetlands and wetland construction for water quality improvement. Scirpus californicus, Typha subulata and Zizaniopsis bonariensis establishment was evaluated under a split plot design, in a factorial experiment with three levels of a water regime factor over a subsoil substratum. The stagnant 10±2 cm water level was best suited to T. subulata and Z. bonariensis development and S. californicus developed better at oscillating water level (3±2 cm) with flooding at 48 hour intervals. The morphological response variables (thickness and width at half length of the tallest leaf or stem per plant, height of tallest leaf or stem per plant, number of green leaves or stems and number of shoots per plant, and survival of propagules' original leaves or stems) were satisfactory descriptors to differentiate (p<0.1%) growth of above ground parts as related to water regimes and species. The three species did survive satisfactory in subsoil-like substratum under the tested water regimes. Mortality was in the worse case, 17.2%, 36.7%, and 9.4% for S. californicus, T. subulata, and Z. bonariensis, respectively. Although Z. bonariensis growth was very poor, only S. californicus and T. subulata could be indicated for planting under similar limiting conditions.


2016 ◽  
Vol 5 (12) ◽  
pp. 5179
Author(s):  
Ilahi Shaik* ◽  
P. Janakiram ◽  
Sujatha L. ◽  
Sushma Chandra

Indole acetic acid is a natural phytohormone which influence the root and shoot growth of the plants. Six (GM1-GM6) endosymbiotic bacteria are isolated from Gracilaria corticata and screened for the production of IAA out of six, three bacterial strains GM3, GM5 and GM6 produced significant amount of IAA 102.4 µg/ml 89.40 µg/ml 109.43 µg/ml respectively. Presence of IAA in culture filtrate of the above strains is further analyzed and confirmed by TLC. As these bacterial strains, able to tolerate the high salinity these can be effectively used as PGR to increase the crop yield in saline soils.


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