Genetic Variation Affecting Agronomic Traits in Sugarcane in Response to High and Low Phosphorus Availability

2014 ◽  
Vol 106 (6) ◽  
pp. 2296-2304 ◽  
Author(s):  
Gustavo da Silveira ◽  
Paulo M. de A. Costa ◽  
Volmir Kist ◽  
Cleverson de F. Almeida ◽  
David Carlos F. Baffa ◽  
...  
2021 ◽  
Author(s):  
João Leonardo Corte Baptistella ◽  
Juan Pablo Portilla Llerena ◽  
Adilson Pereira Domingues‐Júnior ◽  
Alisdair Robert Fernie ◽  
José Laércio Favarin ◽  
...  

2011 ◽  
Vol 91 (1) ◽  
pp. 37-48 ◽  
Author(s):  
M. Cogliatti ◽  
F. Bongiorno ◽  
H. Dalla Valle ◽  
W J Rogers

Fifty-seven accessions of canaryseed (47 populations and 10 cultivars) from 19 countries were evaluated for agronomic traits in four field trials sown over 3 yr in the province of Buenos Aires, Argentina. Genetic variation was found for all traits scored: grain yield and its components (grain weight, grain number per square meter, grain number per head and head number per square meter), harvest index, percent lodging, and phenological characters (emergence to heading, emergence to harvest maturity and heading to harvest maturity). Although genotype × environment interaction was observed for all traits, the additive differences between accessions were sufficient to enable promising breeding materials to be identified. Accessions superior in performance to the local Argentinean population, which in general gave values close to the overall mean of the accessions evaluated, were identified. For example, a population of Moroccan origin gave good yield associated with elevated values of the highly heritable character grain weight, rather than with the more commonly observed grain number per square meter. This population was also of relatively short stature and resistant to lodging, and, although it performed best when sown within the normal sowing date, tolerated late sowing fairly well. Other accessions were also observed with high grain weight, a useful characteristic in itself, since large grains are desirable from a quality point of view. Regarding phenology, the accessions showed a range of 160 degree days (8 calendar days in our conditions) in maturity, which, while not large in magnitude, may be of some utility in crop rotation management. Some accessions were well adapted to late sowing. Grain yield in general was strongly correlated with grain number per square meter. Principal components analysis (PCA) carried out for all characteristics provided indications of accessions combining useful characteristics and identified three components that explained approximately 70% of the phenotypic variation. Furthermore, a second PCA plus regression showed that approximately 60% of the variation in grain yield could be explained by a component associated with harvest index and grain number per square meter. Pointers were provided to possible future breeding targets.Key words: Phalaris canariensis, canaryseed, accessions, yield, phenology, genetics, breeding


Author(s):  
Thien Minh Nguyen ◽  
Tien Thi My Pham

The agronomic values of this population have been evaluated in the field experiments based on their phenotypic performance of agronomic traits, but the genetic variability of this population needs to be evaluated via techniques based on genetic material - DNA. In this study, the genetic variability in the investigated population of 71 hybrids and their parents was evaluated by RAPD technique, using eight selected arbitrarily primers; Genetic parameters and dendrogram expressing the genetic relationships among the investigated population were analyzed by GenALEx 6.1, Popgene 1.31 and NTSYSpc 2.1 softwares. Eight primers were used to generate the amplify products on each individual in the investigated population. From 74 genotypes, a total of 109 fragments were generated, among which, there were 89 polymorphic bands representing 81.65% with an average of 11 polymorphic bands/primer. Genetic similarity coefficient among the investigated population, based on DICE coefficient, ranged from 0.560 (LH05/0822 and PB260) to 0.991 (LH05/0781 and LH05/0841) with an average of 0,796, meaning that the genetic distance among ranged from 0.009 to 0.440 with an average of 0.231. The Shannon index and mean heterozygosity values were 0.328 and 0,176, respectively. This indicated that the progenies of the two investigated crosses possessed a relatively high range of genetic variability. The analysis of molecular variance (AMOVA) showed that genetic variation within population represented 62%, while genetic variation among two different crosses contributes 38% to the total genetic variability. Dendrogram based on DICE’s genetic similarity using UPGMA method showed that the hybrids divide into two major genetic groups (0.75), but the crosses were scattered independently of the hybrid.


2019 ◽  
Vol 48 (3) ◽  
pp. 521-527
Author(s):  
Muhammad Sajjad Iqbal ◽  
Abdul Ghafoor ◽  
Muhammad Akbar ◽  
Shamim Akhtar ◽  
Sammer Fatima ◽  
...  

Thirty two genotypes of Nigella sativa L. were evaluated for three consecutive years which showed significant differences for all the traits indicating high level of genetic variation. Heritability in broad sense ranged from 0.28 to 0.98 and the highest heritability was calculated for days to maturity and days to flowers. Grain yield was positively associated with plant height, capsule weight, capsule length, root length, whereas negatively with capsule width and 1000-seed weight that required the use of novel breeding techniques to break this undesired linkage to improve grain yield in N. sativa. Path coefficient indicated that direct effects of all the traits were positive except days to first flower, days to 50% flowers, flowering duration, number of capsules, root weight and harvest index. The characters exhibiting correlation along with direct effect towards grain yield viz., days to maturity, capsule weight, capsule length and root length should be given more preference while selecting high yielding N. sativa genotypes for future crop improvement programs.


AoB Plants ◽  
2015 ◽  
Vol 7 ◽  
pp. plv097 ◽  
Author(s):  
Yan-Liang Wang ◽  
Marit Almvik ◽  
Nicholas Clarke ◽  
Susanne Eich-Greatorex ◽  
Anne Falk Øgaard ◽  
...  

2004 ◽  
Vol 31 (10) ◽  
pp. 949 ◽  
Author(s):  
Jinming Zhu ◽  
Jonathan P. Lynch

Low soil phosphorus availability is a primary constraint for plant growth in many terrestrial ecosystems. Lateral root initiation and elongation may play an important role in the uptake of immobile nutrients, such as phosphorus, by increasing soil exploration and phosphorus solubilisation. The overall objective of this study was to assess the value of lateral rooting for phosphorus acquisition through assessment of the ‘benefit’ of lateral rooting for phosphorus uptake and the ‘cost’ of lateral roots in terms of root respiration and phosphorus investment at low and high phosphorus availability. Five recombinant inbred lines (RILs) of maize derived from a cross between B73 and Mo17 with contrasting lateral rooting were grown in sand culture in a controlled environment. Genotypes with enhanced or sustained lateral rooting at low phosphorus availability had greater phosphorus acquisition, biomass accumulation, and relative growth rate (RGR) than genotypes with reduced lateral rooting at low phosphorus availability. The association of lateral root development and plant biomass accumulation under phosphorus stress was not caused by allometry. Genotypes varied in the phosphorus investment required for lateral root elongation, owing to genetic differences in specific root length (SRL, which was correlated with root diameter) and phosphorus concentration of lateral roots. Lateral root extension required less biomass and phosphorus investment than the extension of other root types. Relative growth rate was negatively correlated with specific root respiration, supporting the hypothesis that root carbon costs are an important aspect of adaptation to low phosphorus availability. Two distinct cost–benefit analyses, one with phosphorus acquisition rate as a benefit and root respiration as a cost, the other with plant phosphorus accumulation as a benefit and phosphorus allocation to lateral roots as a cost, both showed that lateral rooting was advantageous under conditions of low phosphorus availability. Our data suggest that enhanced lateral rooting under phosphorus stress may be harnessed as a useful trait for the selection and breeding of more phosphorus-efficient maize genotypes.


Sign in / Sign up

Export Citation Format

Share Document