-Studies were conducted to estimate parameters and relationships associated with sub-processes in soil seed banks of oilseed rape in Gorgan, Iran. After one month of burial, seed viability decreased to 39%, with a slope of 2.03% per day, and subsequently decreased with a lower slope of 0.01 until 365 days following burial in the soil. Germinability remained at its highest value in autumn and winter and decreased from spring to the last month of summer. Non-dormant seeds of volunteer oilseed rape did not germinate at temperatures lower than 3.
Fructan accumulation and remobilization to grains under salinity can decrease dependency of the wheat tolerant cultivar on current photosynthesis and protect it from severe yield loss under salt stress. Tolerance of plants to abiotic stresses can be enhanced by accumulation of soluble sugars, such as fructan. The current research sheds light on the role of stem fructan remobilization on yield of bread wheat under salt stress conditions. Fructan accumulation and remobilization as well as relative expression of the major genes of fructan metabolism were investigated in the penultimate internodes of 'Bam' as the salt-tolerant and 'Ghods' as the salt-sensitive wheat cultivars under salt-stressed and controlled conditions and their correlations were analyzed. More fructan production and higher efficiency of fructan remobilization was detected in Bam cultivar under salinity. Up-regulation of sucrose: sucrose 1-fructosyltransferase (1-SST) and sucrose: fructan 6-fructosyltransferase (6-SFT) (fructan biosynthesis genes) at anthesis and up-regulation of fructan exohydrolase (1-FEH) and vacuolar invertase (IVR) genes (contributed to fructan metabolism) during grain filling stage and higher expression of sucrose transporter gene (SUT1) in Bam was in accordance with its induced fructan accumulation and remobilization under salt stress. A significant correlation was observed between weight density, WSCs and gene expression changes under salt stress. Based on the these results, increased fructan production and induced stem reserves remobilization under salinity can decrease dependency of the wheat tolerant cultivar on current photosynthesis and protect it from severe yield loss under salt stress conditions.
-Volunteer canola (Brassica napus) and Sinapis arvensis are well identified weeds of different cropping systems. Quantitative information on regarding seed production by them is limited. Such information is necessary to model dynamics of soil seed banks. The aim of this work was to quantify seed production as a function of the size of those weeds. A wide range of plant size was produced by using a fan seeding system performed at two sowing dates (environments). Plant size varied from 3 to 167 g per plant for canola and from 6 to 104 g per plant for S. arvensis. Seed production ranged from 543 to14,773 seeds per plant for canola, and from 264 to 10,336 seeds per plant for S. arvensis. There was a close relationship between seed production per plant and plant size which was well-described by a power function (y = 130.6x 0.94 ; R 2 = 0.93 for canola and y = 28x 1.27 ; R 2 = 0.95 for S. arvensis). There was also strong relationships among the number of pods produced in individual plants and the quantity of seeds produced (g per plant) with the size of the plant. The relationships found in this study can be used in dynamic seed bank models of volunteer canola and S. arvensis.Keywords: weed, plant size, density, planting.RESUMO -Voluntários de canola (Brassica napus) e Sinapis arvensis são conhecidas como plantas daninhas na produção agrícola. A informação quantitativa sobre a produção de sementes de ervas daninhas por estas é limitada. A informação é necessária para a dinâmica do modelo de bancos de sementes do solo. O objetivo deste trabalho foi quantificar a produção de sementes em função do tamanho destas plantas daninhas. Uma grande variedade de tamanho das plantas foi produzido usando-se um sistema de semeadura em leque, realizado em duas épocas de semeadura (ambientes). O tamanho da planta variou entre 3 e 167 g por planta para a canola e entre 6 e 104 g por planta para S. arvensis. A produção de sementes variou entre 543 e 14.773 sementes por planta de canola e entre 264 e 10.336 de sementes por planta para S.arvensis. Houve uma estreita relação entre a produção de sementes por planta e o tamanho da planta que foi bem descrita por uma função potência (y = 130,6x 0.94 ; R 2 = 0,93 para a canola e y = 28x 1.27 ; R 2 = 0,95 para S. arvensis). Houve também algumas fortes relações entre o número de vagens produzidas em plantas individuais e a quantidade de sementes produzidas (g por planta) com o tamanho da planta. Relações encontradas neste estudo podem ser usadas em modelos dinâmicos do banco de sementes de canola voluntária e S. arvensis.Palavras-chave: planta daninha, tamanho da planta, densidade, plantio.
The aims of this study were to determine the effects of burial on germination and longevity, and of water stress and temperature on germination and dormancy induction of the weed Sinapis arvensis L. During exposure to the high temperatures of summer, seeds buried in the field became nondormant, but low water potential and supra-optimal temperatures (constant not alternating) induced them into secondary dormancy. The threshold temperature for dormancy induction (TTDI) was about 19 °C when water was not limiting germination, and it decreased with a slope of 10 °C per MPa as water potential decreased. Seeds had minimum dormancy (Dmin) when T < TTDI, and Dmin decreased by 81.5% per MPa increase in water potential. Dormancy induction increased linearly with a slope of 13.23% for each additional centimetre of burial depth from 1.0 to 5.19 cm. Dormancy was induced to its highest level (96%) in seeds buried at a depth of ≥5.19 cm; the remaining seeds were dead or were presumed to be dead Sinapis arvensis can form a persistent soil seed bank, and either water stress or conditions associated with increased burial depth can promote induction of secondary dormancy in the seeds.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.