Week Of Germination Research Articles

Accumulated effects of factors determining plant development from somatic embryos of Abies nordmanniana and Abies bornmuelleriana.

Despite a much later inception of somatic embryogenesis (SE) propagation protocols for gymnosperms than for angiosperm species, SE is becoming increasingly important due to its applications for commercial forestry. For many conifers, there are however still major bottlenecks in the SE plant production process limiting the use of SE for forestry operations, Christmas tree production and research projects. In the present case study, the effects on plant growth from different cultural factors applied during the SE developmental process were studied in two conifer species of high value for Christmas tree production. Seven clones of Abies nordmanniana and two clones of Abies bornmuelleriana were included in the study. Accumulated effects from cultural treatments were recorded from the start of germination of mature embryos of different quality scores through development into plants in the third growing period. Experimental factors of the cultural treatments included were: germination temperature, germination time, light conditions, survival ex vitro and traits for plant growth and vitality. The results reveal that most of the studied experimental factors influenced plant growth during the first three years however their relative importance was different. Plant survival rate at end of the nursery stage was strongly impacted by germination temperature (p<0.001), initial embryo score (p=0.007), clone (p<0.001) and to a lesser extend week of germination (p=0.017). This case-study highlights and quantifies the strong interrelation between the developmental steps of somatic embryogenesis and show the importance of considering all cultural steps when optimizing SE plant production protocols.

Evaluation of some organic amendments in combination with the predatory nematode, Fictor composticola against Meloidogyne incognita in cucumber

Effect of different organic amendments (oil cakes, manures, and plant leaves) with Fictor composticola was evaluated against root-knot nematode, Meloidogyne incognita. Organic amendments @ 15 g/kg soil were mixed in pots containing 1 kg sterilized soil. Cucumber (cv. CCH-1) plants grown in these pots were inoculated with 2000 J2 of Meloidogyne incognita and 400 F. composticola per pot, after one week of germination. Root-knot nematode population significantly declined by different organic amendments in the presence of F. composticola. F. composticola with neem cake had the maximum plant weight among all amendments, but maximum root-knot nematode population reduction was recorded in F. composticola with Farm Yard Manure (FYM) followed by F. composticola with neem leaves. Among all organic amendments, the maximum population of F. composticola was found in chicken manure followed by vermicompost. These results indicate that organic amendments can be applied with predatory nematode, Fictor composticola as a promising alternative against M. incognita in cucumber in India.

Transcriptomic and Proteomic Analysis of Drought Stress Response in Opium Poppy Plants during the First Week of Germination.

Water deficiency is one of the most significant abiotic stresses that negatively affects growth and reduces crop yields worldwide. Most research is focused on model plants and/or crops which are most agriculturally important. In this research, drought stress was applied to two drought stress contrasting varieties of Papaver somniferum (the opium poppy), a non-model plant species, during the first week of its germination, which differ in responses to drought stress. After sowing, the poppy seedlings were immediately subjected to drought stress for 7 days. We conducted a large-scale transcriptomic and proteomic analysis for drought stress response. At first, we found that the transcriptomic and proteomic profiles significantly differ. However, the most significant findings are the identification of key genes and proteins with significantly different expressions relating to drought stress, e.g., the heat-shock protein family, dehydration responsive element-binding transcription factors, ubiquitin E3 ligase, and others. In addition, metabolic pathway analysis showed that these genes and proteins were part of several biosynthetic pathways most significantly related to photosynthetic processes, and oxidative stress responses. A future study will focus on a detailed analysis of key genes and the development of selection markers for the determination of drought-resistant varieties and the breeding of new resistant lineages.

Effect of foliar applied triacontanol on wheat (Triticum aestivum L.) under arsenic stress: a study of changes in growth, yield and photosynthetic characteristics

In this study, changes in growth, yield and photosynthetic characteristics were assessed by foliar application of triacontanol (TRIA) in wheat (Triticum aestivum L.) varieties Anaj-2017, Ujala-2016 and AARI-2011under arsenic (As) stress. Seeds of all three wheat varieties were sown in sand filled plastic pots. The experiment was conducted in a completely randomized design (CRD) with three replicates. All the plants were irrigated with full strength Hoagland's nutrient solution till the termination of experiment. Plants were applied with three levels of sodium arsenite (NaAsO2) i.e. 0ppm, 50ppm and 100ppm and two levels of foliar treatment of triacontanol i.e. control (no spray), and TRIA 1µM applied. After 16week of germination, data of all photosynthetic characteristics was collected, while yield was taken at maturity. Arsenic (50ppm and 100ppm) stress exerted significantly adverse effects on various growth and photosynthetic parameters i.e. shoot fresh and dry weights, total leaf area per plant, total grain yield per plant, 100 grain weight, number of seeds per plant, chlorophyll (chl.) pigments, chl. a, b chl. a/b ratio, flavonoids, anthocyanin contents, rate of photosynthesis (A), transpiration rate (E), internal CO2 concentration (C i), water use efficiency (A/E), and stomatal conductance (g s). Foliar application of TRIA significantly increased growth and yield attributes, chlorophyll b, internal CO2 concentration, stomatal conductance, rate of photosynthesis, flavonoids and anthocyanin contents in all wheat varieties. Moreover, the results also indicated that 1µM TRIA proved to be effective in reducing the adverse effects of arsenic stress on all three wheat varieties. Of three wheat varieties, AARI-2011 is more sensitive to arsenic stress and Anaj-2017 proved to be more tolerant against arsenic stress. However, foliar application of TRIA proves to be more effective for var. AARI-2011.

Effect of Arbuscular Mycorrhizal Inoculum Rate on Tomato (Lycopersicum esculenta L.) Seedlings

An experiment on the effect of rate of arbuscular mycorrhiza inoculum in producing tomato seedlings (var. Ratan) were conducted in the seedbed of Soil Science Division, Bangladesh Agricultural Research Institute, Joydebpur, Gazipur, Bangladesh during rabi season of 2007-08 and 2008-09. Seven rates of AM inoculum viz. 0, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0 kg m-2 were studied on tomato seedlings. Cowdung was used at the rate of 5 kg m-2 as basal. Seeds were sown in 10 cm apart solid lines on 13 November 2007 and 11 November 2008, and the seedlings were thinned down to about 3 cm from seedling to seedling within a week of germination. Ratan was used as the variety of tomato. Biomass yield, seedling height and nutrient uptake by tomato seedlings increased greatly with the use of AM inoculum. Biomass yield of tomato seedlings followed quadratic trend with the increase of AM inoculum rate from 0 to 1.0 kg m-2 in 2007-08 and 0 to 2.0 kg m-2 in 2008-09.Bangladesh J Microbiol, Volume 29, Number 2, Dec 2012, pp 104-108

K-priming positively modulates growth and nutrient status of salt-stressed cotton (Gossypium hirsutum) seedlings

ABSTRACTBeing macronutrient, K+ is involved in a number of metabolic processes including stimulation of over 60 enzymes. The present study was conducted to investigate whether K-priming could alleviate the effects of salinity on the growth and nutrient status of cotton seedlings. The seeds of two cotton cultivars, namely FH-113 and FH-87, were primed with solutions of three potassium sources (KNO3, K2SO4 and K2HPO4) using three concentrations (0%, 1.25% and 1.5%) of each potassium source. After 1 week of germination, the seedlings were subjected to salinity (0 and 200 mM NaCl) stress. The results showed that salinity significantly affected growth and nutrients status of cotton seedlings. The K-priming alleviated the stress condition and significantly improved dry matter as well as nutrient uptake in cotton seedlings. Of the priming treatments pre-sowing treatment with KNO3 (1.5%) was most effective in increasing shoot and root lengths and biomass of cotton seedlings. The seedlings raised from seed treated with KNO3 (1.5%) showed varied accumulation of cations (Ca2+, Na+ and K+) and faced less oxidative stress irrespective of cotton cultivars under salt stress. The results suggested that pre-sowing seed treatment with KNO3 (1.5%) might be recommended for synchronized germination and sustainable production of cotton crop under saline environments.

Effect of rate of arbuscular mycorrhiza inoculum on Tomato (Solanum lycopersicum) seedlings

An experiment on the effect of rate of Arbuscular mycorrhiza (AM) inoculum on tomato seedlings was conducted at Bangladesh Agricultural Research Institute, Joydebpur, Gazipur, Bangladesh for two consecutive years. Seven rates of AM inoculum viz., 0, 0.5, 1.0, 1.5, 2.0, 2.5, and 3.0 kg/m2 were tested. Cowdung was used at a rate of 5 kg/m2. Seeds were sown in 10 cm apart lines on 13 November 2007 and 11 November 2008, and the seedlings were thinned out to about 3 cm from seedling to seedling within a week of germination. Roma VF was used as a variety of tomato. Biomass yield, root colonization, spore number, and nutrient uptake by tomato seedlings increased remarkably with the rates of AM inoculum. The biomass yield followed a quadratic trend with the increase of AM inoculum rate from 0 to 2.0 kg/m2 in 2007-08 and 0 to 1.5 kg/m2 in 2008-09. DOI: http://dx.doi.org/10.3329/bjar.v38i3.16974 Bangladesh J. Agril. Res. 38(3): 473-480, September 2013

The performance of weaned albino rats (Wister strain) fed Baobab (&lt;i&gt;Adansonia digitata&lt;/i&gt;) leave-based diets

Adansonia digitata seeds were cultivated and their seedling leaves were harvested in large quantities. The seedling leaves were dried and analysed for proteins, lipids and carbohydrates using microjedahl, soxhlet and UV analytical tools respectively. This was done on weekly basis starting from 4th week of germination. The seedling leaf was found to have the highest crude protein value of 13.57% obtained at 6th week after germination. Two diets prepared from A. digitata leaf were fed parallel into albino rats with diets containing roasted full fat soyabean as control. The result reveals that A. digitata leaves can be included in the diet of albino rats at up to 20% level without depression in performance of feed intake, body weight gain and feed to gain ration (feed conversion ratio). Keywords: Rats, protein, performance, Adansonia digitata, Soya bean

Developmental Studies in Porphyra Vietnamensis: a High-Temperature Resistant Species from the Indian Coast

Porphyra vietnamensis Tanaka & Pham-Hoang Ho (Bangiales, Rhodophyta) is a tropical seaweed collected from the west coast of India. Thalli of the blade phase are found growing only during the rainy season between July and September. They grow on rocky intertidal or subtidal substrata or as epiphytes on other seaweeds such as Enteromorpha flexuosa and Chaetomorpha media. The gametophytic thallus is monostromatic and covered with spines at the base. The species is monoecious. Male gametangia are found in patches that are distributed in the upper part of the thallus. Archeospores are found at the thallus margins and give rise to the blade phase after one week of germination even at 30°C. Zygotospores germinated at 25°C into conchocelis within three days from the date of their inoculation. Conchospores were released at 30°C. The young blades grew at 32°C in the laboratory.

Seed germination studies of Salvadora persica and Jatropha curcas

In nature the seeds of Salvadora persica and Jatropha curcas possess diversity in their size. Based on their weight, the seeds were segregated into seven categories. In S. persica these ranged from 20 to 90 mg per seed while in J. curcas ranged from 100 to 800 mg per seed. When put to germination, there was no germination at all in seeds weighing up to 30 mg per seed in S. persica and up to 300 mg per seed in J. curcas. The germination was found to be 22, 29, 49, 64, 89 and 100% in S. persica in rest of the six categories while in J. curcas it was found to be 20, 30, 60, 85 and 100% in remaining five categories. The seedling development in terms of height and fresh biomass also increased with the increase in seed weight. When treated with salt solution adjusted to different pH levels (2 to 11), the seed germination was found highest in both species at pH 8.0. The germination was faster at pH from 6 to 8 when compared to other levels. The effect of quality of light on seed germination showed maximum germination in natural light in both the species followed by yellow, green, red and blue lights, respectively. The seed germination was initiated after one week when seeds were treated with saline water of electric conductivity of 2 and 4 dS m-1 in both the species while on higher salinity the germination started during second week. The seed germination was lower at higher salinity. After 4th week of germination the shoot length, root length, collar diameter, fresh and dry biomass of shoot and root were decreased with increase in the salinity of irrigation water.

A Metal-binding Member of the Late Embryogenesis Abundant Protein Family Transports Iron in the Phloem ofRicinus communis L.

The transport of metal micronutrients to developing organs in a plant is mediated primarily by the sieve elements. Ligands are thought to form complexes with the free ions in order to prevent cellular damage, but no binding partners have been unequivocally identified from plants so far. This study has used the phloem-mediated transport of micronutrients during the germination of the castor bean seedling to identify an iron transport protein (ITP). It is demonstrated that essentially all (55)Fe fed to seedlings is associated with the protein fraction of phloem exudate. It is shown that ITP carries iron in vivo and binds additional iron in vitro. ITP was purified to homogeneity from minute amounts of phloem exudate using immobilized metal ion affinity chromatography. It preferentially binds to Fe(3+) but not to Fe(2+) and also complexes Cu(2+), Zn(2+), and Mn(2+) in vitro. The corresponding cDNA of ITP was cloned using internal peptide fragments. The deduced protein of 96 amino acids shows high similarity to the stress-related family of late embryogenesis abundant proteins. Its predicted characteristics and its RNA expression pattern are consistent with a function in metal ion binding. The ITP from Ricinus provides the first identified micronutrient binding partner for phloem-mediated long distance transport in plants and is the first member of the late embryogenesis abundant protein family shown to have such a function.

Effect of germination on the ribonucleic acids (RNA) of some legume seeds ( Vicia faba, Cicer arietinum and Lupinus termes)

The present study was carried out in order to evaluate some Egyptian legume seeds ( Vicia faba, Cicer arietinum and Lupinus termes) as raw and germinated foods, as sources of plant proteins. The work was extended to study the changes of nucleic acids (28S RNA, 18S RNA, 16S RNA, 5.8S RNA, 5S RNA, 4.5S RNA and tRNA) content and distribution during 1 week of germination using HPLC and electrophoresis techniques. The results are summarised as follows. (1) The RNAs from the first day of germination of seeds and roots were separated into five major types: 28/18S RNA, 16S RNA, 5.8S RNA, 5S RNA and tRNA. (2) The RNAs at the seventh day of germination in both seeds and roots are 16S RNA, 5S RNA, 4.5S RNA and tRNA, in addition to two degradation regions in the range of 28/18S RNA and tRNA. Also, appearance of new RNA (mainly 4.5S RNA, a chloroplast RNA) and disappearance of 5.8S RNA, which was present at the first day of germination, were as expected after 7 days of germination. (3) The 24 h germinated seeds have a mature and complete set of the RNA species which means that the synthesis of these RNA species already occurred during the first 24 h of imbibition. (4) A new buffer system for separating the total RNA into their species, 28/18S RNA, 5S RNA and tRNA by the HPLC technique, is also reported.

The changes of protein patterns during one week of germination of some legume seeds and roots

This study was carried out in order to evaluate some Egyptian legume seeds ( Vicia faba, Cicer arietinum and Lupinus termes) as raw and germinated foods, as sources of plant proteins. The work was extended to study the changes of the seed and root proteins during 7 days of germination. The results are summarised as follows: (1) The proteins of ungerminated seeds were resolved on SDS-PAGE into a number of bands and their molecular weights were determined: chick-peas, 19 (8–78 kDa); faba beans, 20 (11–96 kDa) and lupins 19 (14–86 kDa). (2) The changes in the seed and root proteins during 7 days of germination of the V. faba, C. arietinum and L. termes showed the following: • • The number of seed bands of C. arietinum, V. faba and L. termes at the first day were 19 (12–89 kDa), 25 (12–98 kDa) and 16 (12–98 kDa); they decreased up to the seventh day of germination to 12, 22 and 9 bands, respectively. The number of root bands were 13 (13.5–89 kDa), 23 (12–98 kDa) and 19 (13–96 kDa), respectively. • • The number of seed stable (constant) proteins during the 7 days of germination were 8, 4 and 0 proteins for C. arietinum, V. faba and L. termes, respectively. The roots contained 4, 3 and 1 proteins, respectively. • • V. faba and L. termes were the predominant seeds, containing high-molecular-weight reserve proteins which degraded and disappeared within the first 3 days of germination to give smaller peptides or amino acids. New synthesised proteins were found and this was especially marked in L. termes seeds. • • It was noticed that all three seeds contained newly synthesised proteins, mainly up to the third day of germination and the numbers of these proteins were found to be 4, 4 and 3 proteins for C. arietinum, V. faba and L. termes, respectively. In roots there were 5, 4 and 0 proteins, respectively.

Amide-Linked Indoleacetic Acid Conjugates May Control Levels of Indoleacetic Acid in Germinating Seedlings of Phaseolus vulgaris

We have shown that amide-linked IAA (indole-3-acetic acid) conjugates accumulated to high levels during maturation of bean seeds (K. Bialek and J.D. Cohen [1989] Plant Physiol 91: 775-779). In the present study, we were interested in the fate of these and other IAA conjugates during seed germination. The content of amide-linked conjugates of IAA in cotyledons declined dramatically during the first hours of imbibition. The rate of decline slowed markedly during the period of the resumption of axis growth. The level of amide-linked IAA conjugates in cotyledons remained relatively high after almost 1 week of germination. The decline of IAA conjugates in cotyledons was followed by a steady increase in the content of both free and amide-linked IAA in the embryonic axes. Amide-linked IAA conjugates were also present in the axes cultured on agar after the cotyledons were removed, which suggests that de novo production of these IAA conjugates occurs in the axis of germinating bean seedlings. A comparison of relative amounts of free and conjugated IAA in the axes of intact seedlings and axes cultured on agar showed lower levels of free IAA and higher levels of conjugated IAA in much slower growing isolated axes. These results suggest a more general role for IAA conjugates in the control of seedling growth than simply to serve as a seed storage form of auxin.

Ferritin accumulation and degradation in different organs of pea (Pisum sativum) during development

Iron concentration and ferritin distribution have been determined in different organs of pea (Pisum sativum) during development under conditions of continuous iron supply from hydroponic cultures. No ferritin was detected in total protein extracts from roots or leaves. However, a transient iron accumulation in the roots, which corresponds to an increase in iron uptake, was observed when young fruits started to develop. Ferritin was detectable in total protein extracts of flowers and pods, and it accumulated in seeds. In seeds, the same relative amount of ferritin was detected in cotyledons and in the embryo axis. In cotyledons, ferritin and iron concentration decrease progressively during the first week of germination. Ferritin in the embryo axis was processed, and disappeared, during germination, within the first 4 days of radicle and epicotyl growth. This degradation of ferritin in vivo was marked by a shortening of a 28 kDa subunit, giving 26.5 and 25 kDa polypeptides, reminiscent of the radical damage occurring in pea seed ferritin during iron exchange in vitro [Laulhere, Laboure & Briat (1989) J. Biol. Chem. 264, 3629-3635]. Developmental control of iron concentration and ferritin distribution in different organs of pea is discussed.

Dynamics of indole-3-acetic acid during germination of Picea abies seeds

High performance liquid chromatography and combined gas chromatography-mass spectrometry were used to identify indole-3-acetic acid (IAA) and indole-3-ethanol as endogenous constituents of germinating Norway spruce (Picea abies (L.) Karst.) seeds. Indole-3-methanol was tentatively identified by multiple ion monitoring. The free IAA content of the seeds rose from about 20 ng g(-1) to about 60 ng g(-1) (dry weight) during the first five days of germination and thereafter declined to around 20 ng g(-1). Indole-3-acetic acid released by alkaline hydrolysis, which was initially present at about 110 ng g(-1), decreased to 5-10 ng g(-1) during the first week of germination. The IAA content of seed lots differing in germination behavior was investigated. The findings are discussed in relation to the metabolism of IAA in conifer seeds.

Ontogenetic changes in isozyme patterns during seed germination of self-pollinatedSecale species

Six isozymatic systems have been studied comparatively during the first week of germination of seeds of self-pollinatedSecale species (S. silvestre Host. andS. vavilovii Gross.). Isozymatic systems do not change at all, or reach their definitive adult plant pattern early during germination.

Precociously germinating rapeseed embryos retain characteristics of embryogeny

We compared the germination of Brassica napus L. embryos at three stages of development-mid-cotyledon, maturation and mature dry-to determine at which stage they acquired the capacity for normal germination and seedling development. Embryos were removed from the seed and cultured on hormone-free medium, allowing them to germinate. The transition from embryogeny to germination was monitored both morphologically and biochemically, using synthesis of 12 S storage protein as a marker of embryogeny. The mature embryos (dry seeds) set the standard for normal seedling development: radicle emergence, hypocotyl extension and cotyledon expansion occurred within 2 d and true leaves were formed within a week of germination. Rocket immunoelectrophoresis indicated that the storage proteins in seedlings from mature dry embryos were completely degraded within a week. In contrast, the midcotyledon-stage embryos appeared to germinate abnormally, retaining many embryonic characteristics. Although the roots emerged, the hypocotyls did not elongate and secondary cotyledons instead of leaves were formed at the shoot apex. Also, the seedlings continued to synthesize and accumulate storage proteins. The maturation-stage embryos did develop into normal-looking seedlings, but complete degradation of storage proteins required several weeks, presumably reflecting continued synthesis and turnover. We conclude that embryogenic and germination-specific processes can occur concurrently and that the capacity to develop as normal seedlings is acquired gradually during the maturation process.

Lipoxygenase Activities in Developing and Germinating Soybean Seeds with and Without Lipoxygenase-1

Dry-matter accumulation, extracted protein, lipoxygenase-1 (L-1), and lipoxygenase-2 plus -3 (L-2 plus -3) were investigated in two genotypes and two genotypes lacking L-1 activity in mature seeds. Dry-matter accumulation patterns during seed development were similar in all four genotypes. Protein extracted during seed development or the first week of germination also showed similar profiles for the four genotypes. Changes in L-2 plus -3 activity per milligram extracted protein and total L-2 plus -3 activity per seed again showed similar profiles for all four genotypes during seed development and germination. L-2 plus -3 activity was maximal between days 5 and 20 before physiological maturity and again maximal between days 4 and 7 of germination. The two soybean genotypes that did not have L-1 activity in mature seeds also lacked detectable L-1 activity throughout seed development and the first week of germination. The two normal soybean genotypes displayed similar profiles of L-1 activity. L-1 a...

The Relationship between Growth and Indole-3-Acetic Acid Content of Roots of Pisum sativum L.

The indole-3-acetic acid (IAA) content of roots and shoots of light-grown pea seedlings (Pisum sativum L. `Little Marvel') growing at different rates was studied by radioimmunoassay during the first week of germination. Different growth rates were obtained by daily irrigation with either deionized water or a dilute Hoagland's mineral nutrient solution. Mineral nutrient-grown roots grew more rapidly, had more lateral roots, and initiated lateral roots at a greater distance from the apex than did water-grown roots. Growth kinetics with both treatments were biphasic. There was an initial phase of rapid cell expansion lasting about 3 days during which growth was insensitive to external mineral nutrient supply. This was followed by a slower growth phase consisting of a balance between cell division and cell expansion. Withholding nutrients resulted in the progressive inhibition of cell division during this second phase. At no time did the amount of IAA per gram fresh weight or the number of cells per gram fresh weight differ significantly in roots treated with water or mineral nutrients, whereas the total amount of IAA per organ and the total number or cells per organ were greater in roots provided with nutrients. The amount of IAA per gram fresh weight changed dramatically in roots during the first week of germination, but this was correlated with changes in the relative contributions of cell division and cell expansion to fresh weight growth rather than to growth rate. By contrast, the amount of IAA per gram fresh weight in 3-mm root tips showed a direct relationship with growth rate. The relationship between IAA content and growth in whole shoots was qualitatively and quantitatively similar to that found in whole roots.