Seed coating reduces respiration losses and affects sugar metabolism during germination and early seedling growth in cereals

2015 ◽  
Vol 42 (2) ◽  
pp. 209 ◽  
Author(s):  
Linda Gorim ◽  
Folkard Asch

Seed germination and the successful establishment of young seedlings is an important aspect of plant life. Seed coats are used to improve stand establishment and early seedling vigour. Seedlings growing from hydro-absorber coated barley, rye and wheat with coat-shares greater than 75% of the average seed have been shown to promote better seedling growth compared with those seedlings growing from uncoated seeds. We investigated how and why these seedlings performed better by analysing the proportion of grain reserves mobilised for growth and respiration as well as how both sucrose and glucose available in the embryo translated into seedling growth in the presence or absence of seed coats containing hydro-absorber gel. We found that mobilisation efficiency was higher, resulting in higher biomass in these cereals when they were coated. The relationship between sucrose and glucose available to the seedling as well as its correlation with early seedling growth indicate a switch in the enzymatic cleavage of embryonic sucrose from invertase to sucrose synthase. This in turn indicates that in coated seeds, embryonic tissue must be hypoxic leading to a more efficient use of glucose and thus reduced respiration losses during germination.

Author(s):  
Ruqiang Tong ◽  
Xinyuan Liu ◽  
Bifan Mu ◽  
Junfeng Wang ◽  
Mengxing Liu ◽  
...  

Background: Understanding the drought tolerance of white clover seeds during germination and early seedling growth and how that is linked to seed maturation in legume species, is crucial to developing new stand establishments.Methods: An experiment was conducted in Randomized Block design in two factorial concept to explore how seed maturation and drought tolerance influence seed germination and early seedling growth using the two factors: seed coat color (yellow and brown, two levels as one factor) and drought intensity (control: 0 MPa [distilled water], mild drought: -0.2 MPa, moderate drought: -0.4 MPa and severe drought: -0.6 MPa, four levels as another factor).Result: In contrast to the yellow-coated seeds, the mean germination percentage, germination index, seedling vigour index and radicle length of the brown-coated seeds were lowered by 7.9%, 23.1%, 20.5% and 12.9%, respectively. Compared to the control, introducing drought conditions reduced the mean of germination percentage, germination index, seedling vigour index and radicle length of yellow-coated seeds by 52.4%, 64.1%, 41.9% and 23.2%, respectively. Meanwhile, drought affected brown-coated seeds more than yellow-coated seeds. The results indicating that the seed quality of white clover seed lots with yellow-colored coats higher than the seed lots with brown-coloured coats. In agronomic practice, a larger proportion of yellow-coated seeds should be harvested to improve new stands successful establishment under environment easy to dry.


Agronomy ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 566
Author(s):  
Shyama Prashad Chakma ◽  
Stephen Mushimwa Chileshe ◽  
Richard Thomas ◽  
Priti Krishna

Cotton (Gossypium hirsutum) is the largest fibre crop globally and an important oilseed crop. Rising temperatures and declining water supplies, which are also impacting soil salinity, threaten cotton plant productivity. Germination, emergence and young seedling stages in cotton are highly sensitive to salinity and heat stresses. Brassinosteroids (BRs) are plant steroid hormones that are essential for proper plant growth and development and also promote tolerance to a range of environmental stresses. Cotton seeds were primed with BR (24-epibrassinolide) alone or in combination with other hormones (abscisic acid, auxin and gibberellic acid) and tested for germination and early seedling growth. BR promoted germination under no stress as well as under salinity and heat stress conditions, while other hormones were ineffective under stress conditions. BR also promoted cotyledon opening and the development of lateral roots in germinated seedlings. The ability of BR to positively impact seedling growth across different stress conditions suggests that priming cotton seeds with BR may help in early and successful establishment of seedlings, which may benefit the plant through its lifecycle.


Author(s):  
R. Himaja ◽  
K. Radhika ◽  
K. Bayyapu Reddy ◽  
M. Raghavendra

Background: Drought stress at germination and early growth stages hinders the seedling establishment in chickpea which ultimately affects the economic yield. Such adverse affects of drought can be mitigated by screening and identifying the tolerant genotypes of chickpea which is commonly cultivated under rain-fed conditions during post-rainy season. Methods: Effect of drought stress on germination and early seedling growth of thirty three chickpea genotypes was studied under four different concentrations of PEG 6000 (-0.3, -0.6, -0.9 and -1.2 MPa) along with control and hydration under laboratory conditions during 2018-19. Result: Significant variation was observed among the genotypes for germination, root length, shoot length and seedling vigour index under different concentrations of PEG 6000. Complete inhibition of germination was observed in most of the genotypes at -1.2 MPa. Based on the results obtained, JG 11 and NBeG 3 were considered as tolerant since they showed comparatively higher germination, root length, shoot length and seedling vigour even at -1.2 MPa, while NBeG 723 and NBeG 833 were considered as susceptible genotypes because of their poor germination and seedling growth even at lower levels of drought stress.


2017 ◽  
Vol 45 (2) ◽  
pp. 282-295
Author(s):  
R. Vihotogbé ◽  
C. Watson ◽  
R. Glèlè Kakaï ◽  
F. Wichern ◽  
B. Sinsin ◽  
...  

Plants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 323
Author(s):  
Sujuan Shi ◽  
Lulu An ◽  
Jingjing Mao ◽  
Oluwaseun Olayemi Aluko ◽  
Zia Ullah ◽  
...  

CBL-interacting protein kinase (CIPK) family is a unique group of serine/threonine protein kinase family identified in plants. Among this family, AtCIPK23 and its homologs in some plants are taken as a notable group for their importance in ions transport and stress responses. However, there are limited reports on their roles in seedling growth and development, especially in Solanaceae plants. In this study, NtCIPK23, a homolog of AtCIPK23 was cloned from Nicotiana tabacum. Expression analysis showed that NtCIPK23 is mainly expressed in the radicle, hypocotyl, and cotyledons of young tobacco seedlings. The transcriptional level of NtCIPK23 changes rapidly and spatiotemporally during seed germination and early seedling growth. To study the biological function of NtCIPK23 at these stages, the overexpressing and CRISPR/Cas9-mediated knock-out (ntcipk23) tobacco lines were generated. Phenotype analysis indicated that knock-out of NtCIPK23 significantly delays seed germination and the appearance of green cotyledon of young tobacco seedling. Overexpression of NtCIPK23 promotes cotyledon expansion and hypocotyl elongation of young tobacco seedlings. The expression of NtCIPK23 in hypocotyl is strongly upregulated by darkness and inhibited under light, suggesting that a regulatory mechanism of light might underlie. Consistently, a more obvious difference in hypocotyl length among different tobacco materials was observed in the dark, compared to that under the light, indicating that the upregulation of NtCIPK23 contributes greatly to the hypocotyl elongation. Taken together, NtCIPK23 not only enhances tobacco seed germination, but also accelerate early seedling growth by promoting cotyledon greening rate, cotyledon expansion and hypocotyl elongation of young tobacco seedlings.


Sign in / Sign up

Export Citation Format

Share Document